GEOGRAPHICAL ABSTRACTS: PHYSICAL GEOGRAPHY Edited by the Elsevier BD Editorial Team F.K. Cooper N.T. Davey N.M. Dunwell L.E. Evans J.H. Harris J.C. Hodson N.E. Jode S.E. Long J.W. Sperry C.J. Towers L.E. Walker Elsevier BD Helpdesk ELSEVIER Bibliographic Databases (BD) The Old Bakery 111 Queens Road Norwich, NR1 3PL United Kingdom Tel: +44 1603 626327 Fax: +44 1603 667934 E-mail: ebd-marketing@elsevier .com Website: www.elsevier.com/geobase Copyright E 2006 Elsevier B.V., Amsterdam. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, electrostatic, magnetic tape, mechanical, photocopying, recording or otherwise, without the prior written permission of the publisher, Elsevier B.V., Radarweg 29, 1043 NX Amsterdam, The Netherlands. 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Electronically processed and printed by Scan Laser B.V., Zaandam, The Netherlands RECORD FORMAT Chapter heading PALAEONTOLOGY Sub-chapter heading Palaeobotany Title of article in English Item number 11726 Santa Lucia superiore (Toirano, Liguria): Ligurian vegetation history during the Lower Pleniglacial (French) Non-English title (Santa Lucia superiore (Toirano, Ligurie): Reconstitution locale de la végétation ligure durant le Pléniglaciaire ancien) Author name(s) Kaniewski D., Renault-Miskovsky J., Tozzi C. and de Lumley H. Journal title Geobios 2005 39/3 (353-364) Page numbers of the article in the original journal Year of publication, volume number and issue number Abstract in English Article language Pollen analysis of Santa Lucia superiore cave (Italy) reports at local scale the lowland Ligurian vegetation during the Lower Pleniglacial (75 to 57 Kyr BP). The pollen profile shows two AP extensions during a steppe-landscape episode in Liguria. The dry and cold phases caused the establishment of a steppe-landscape (NAP 92%) with Artemisia, Ephedra, Poaceae and Chenopodiaceae, similar to those mentioned in the Latium during the Pleniglacial. The increase of moisture generated a first arboreal extension (Pinus, Betula, Corylus, Ulmus), which engendered the formation of an open-forest landscape (AP 43%). The second arboreal extension (AP 55%) was due to an increase of moisture and higher temperatures, which allowed the development of Mediterranean trees and shrubs (Quercus ilex, Olea, Phillyrea). This warming up occurred probably simultaneously with a secondary transgression during the glacial sea-level change. The upper part of the profile shows an open vegetation, which indicates the return of a steppe-landscape. Pollen data, replaced in the multidisciplinary studies of the site, are well correlated with the fauna and sediment data. E 2005 Elsevier SAS. All rights reserved. GEOGRAPHICAL ABSTRACTS: PHYSICAL GEOGRAPHY CONTENTS Page SYNOPTIC GEOGRAPHY Global change Pollution Biogeochemical cycles Modelling and numerical methods International programmes 265 265 - LANDFORMS Weathering and related landforms Fluvial landforms Coastal landforms Volcanic landforms Arid landforms Regional physiography Neotectonics and structural control Landforms of other planets Slopes Soil mechanics Karst Anthropogenic landforms 267 267 270 271 271 272 273 274 276 277 278 THE QUATERNARY Chronology Palaeoclimatology Oceans Tropics and sub-tropics Mid-latitude and extra-glacial Glacial landforms and sediments The Holocene Sea level Periglacial Glaciology 278 280 289 293 293 294 295 297 297 SEDIMENTOLOGY Methods, equipment and programs Sediments and sedimentary processes - physical properties Sediments and sedimentary processes - transport Sediments and sedimentary processes - deposition Sediments and sedimentary processes - diagenesis Sedimentary geochemistry Sedimentary environments - terrestrial Sedimentary environments - coastal and shallow marine Sedimentary environments - oceanic Applied sedimentology 302 302 305 312 313 315 317 318 318 SOILS Regional and survey Methods Genesis and formation Physical properties Soil water Mineralogy Chemistry Organic matter Biota Contamination and remediation Erosion and conservation 320 321 322 324 326 329 336 341 347 354 HYDROLOGY Precipitation assessment Precipitation quality Interception, throughfall and stemflow Evaporation and transpiration 359 360 363 364 365 continued on next page Runoff, streamflow and basins Channel hydraulics and sediment transport Lakes and reservoirs Wetlands and estuaries Surface water quality runoff and soil water rivers and streams lakes and reservoirs Groundwater processes vadose zone phreatic zone Groundwater quality vadose zone phreatic zone Glacial hydrology Land use, forestry and agriculture Water resources and management METEOROLOGY AND CLIMATOLOGY Instrumentation Radiation Atmospheric electricity Optics Regional weather patterns Synoptic meteorology Boundary layer meteorology Air-sea interaction Dynamic meteorology large scale mesoscale Convection and cloud microphysics Rainfall processes Weather and climate forecasting Climate change Atmospheric chemistry Aerosols Atmospheric pollution 367 383 388 389 391 395 399 407 409 412 414 417 422 423 426 427 429 434 436 437 441 443 444 449 455 456 461 463 467 468 472 477 484 495 REMOTE SENSING, GIS AND MAPPING Remote sensing primary data capture secondary data capture geodesy numerical and image analysis GIS methodology error, accuracy, quality, legislation software and systems Mapping Map curatorship and history Cartography Applications atmosphere lithosphere biosphere hydrosphere human 518 520 521 526 528 GENERAL TEXTS 529 508 509 509 512 516 516 516 517 517 265 SYNOPTIC GEOGRAPHY Global change 1401 Salt lakes in Australia: Present problems and prognosis for the future Timms B.V. Hydrobiologia 2005 552/1 (1-15) Australia is a land of salt lakes and despite low human population density, many lakes are adversely impacted by a range of factors. Secondary salinisation is the most pernicious force degrading lakes, especially in south-west Western Australia where up to 30% of the landscape is predicted to be affected. Mining also impinges on many salt lakes in this state, mainly through the dewatering of saline groundwater. Exploitation of groundwater for irrigation caused some lakes in Victoria, Australia, to dry, especially the significant Red Rock Complex. Global climate change will result in new water balances in endorheic lakes, with most having less water, particularly the seasonal lakes of southern Australia. This has already happened in Lake Corangamite, Victoria, but the prime reason is diversion of inflowing floodwater. Consequently, the lake has retreated and become salinised compromising its status as a Ramsar site. Various other lakes suffer from enhanced sedimentation, have introduced biota or their catchments are being disturbed to their detriment. Enlightened management should be able to maintain some important lakes in an acceptable condition, but, for most others, the future is bleak. © Springer 2005. 1402 Assessing the future global impacts of ozone on vegetation Ashmore M.R. Plant, Cell and Environment 2005 28/8 (949-964) Ozone is a major secondary air pollutant, the current concentrations of which have been shown to have significant adverse effects on crop yields, forest growth and species composition. In North America and Europe, emissions of ozone precursors are decreasing but in other regions of the world, especially Asia, where much less is known about its impacts, they are increasing rapidly. There is also evidence of an increase in global background ozone concentrations, which will lead to significant changes in global ozone exposure over this century, during which direct and indirect effects of other changes in the global atmosphere will also modify plant responses to ozone. This paper considers how far our current understanding of the mechanisms of ozone impacts, and the tools currently used for ozone risk assessment, are capable of evaluating the consequences of these changing global patterns of exposure to ozone. Risk assessment based on relationships between external concentration and plant response is inadequate for these new challenges. New models linking stomatal flux, and detoxification and repair processes, to carbon assimilation and allocation provide a more mechanistic basis for future risk assessments. However, there are a range of more complex secondary effects of ozone that are not considered in current risk assessment, and there is an urgent need to develop more holistic approaches linking the effects of ozone, climate, and nutrient and water availability, on individual plants, species interactions and ecosystem function. © 2005 Blackwell Publishing Ltd. 1403 The cryosphere and global environmental change: Some geomorphic perspectives Slaymaker O. Chikei/Transactions, Japanese Geomorphological Union 2005 26/4 (359-370) A consideration of the global environmental changes affected by the cryosphere. The components of the terrestrial cryosphere (glaciers, snow, permafrost and lake and river ice) are analysed independently and also in the context of their influence on, and response to human activity in, large river basins tributary to the Arctic Ocean. Some of the geomorphic concepts that are thought to be important in interpreting these cryospheric changes are: thresholds, systems, complex response, resistance, panarchy, collapse and Yatsu’s idea that "anything goes ". Biogeochemical cycles 1404 Effect of potassium phosphate fertilization on production and emission of methane and its 13 C-stable isotope composition in rice microcosms Conrad R. and Klose M. Soil Biology and Biochemistry 2005 37/11 (2099-2108) Rice fields are an important source for atmospheric CH4 , but the effects of fertilization are not well known. We studied the turnover of CH 4 in rice soil microcosms without and with addition of potassium phosphate. Height and tiller number of rice plants were higher in the fertilized than in the unfertilized microcosms. Emission rates of CH4 were also higher, but porewater concentrations of CH4 were lower. The 13 C values of the emitted CH4 and of the CH 4 in the porewater were both 2-6% higher in the fertilized microcosms than in the control. Potassium phosphate did not affect rate and isotopic signature of CH4 production in anoxic soil slurries. On the other hand, roots retrieved from fertilized microcosms at the end of incubation exhibited slightly higher CH4 production rates and slightly higher CH4 - 13 C values compared to roots from unfertilized plants. Addition of potassium phosphate to excised rice roots generally inhibited CH4 production and resulted in increasingly lower 13 C values of the produced CH4 . Fractionation of 13 C during plant ventilation (i.e. 13 C in pore water CH4 versus CH4 emitted) was larger in the fertilized microcosms than in the control. Besides plant ventilation, this difference may also have been caused by CH4 oxidation in the rhizosphere. However, calculation from the isotopic data showed that less than 27% of the produced CH4 was oxidized. Collectively, our results indicate that potassium phosphate fertilization stimulated CH4 emission by enhancing root methanogenesis, plant ventilation and/or CH4 oxidation, resulting in residence times of CH4 in the porewater in the order of hours. © 2005 Elsevier Ltd. All rights reserved. 1405 Enhanced iron reduction by iron supplement: A strategy to reduce methane emission from paddies J¨ackel U., Russo S. and Schnell S. Soil Biology and Biochemistry 2005 37/11 (2150-2154) As an option for mitigating methane emissions from rice paddies the effects of ferrihydrite application to an experimental field plot at the beginning of the growth season was studied. Methane emissions during the vegetation period of rice were significantly lower (50%) in the fertilized plot compared to the non-supplemented control plot. Although toxic effects of iron are known to occur with wetland plants including rice, our field experiment showed no deterioration of agrophysiological data. Grain yield, harvest index, and iron content of grains were not different in the two plots. Therefore, we propose that iron application is a suitable strategy to reduce methane emission from rice paddies. © 2005 Elsevier Ltd. All rights reserved. 1406 Microbial responses and nitrous oxide emissions during wetting and drying of organically and conventionally managed soil under tomatoes Burger M., Jackson L.E., Lundquist E.J. et al. Biology and Fertility of Soils 2005 42/2 (109-118) The types and amounts of carbon (C) and nitrogen (N) inputs, as well as irrigation management are likely to influence gaseous emissions and microbial ecology of agricultural soil. Carbon dioxide (CO2 ) and nitrous oxide (N2 O) efflux, with and without acetylene inhibition, inorganic N, and microbial biomass C were measured after irrigation or simulated rainfall in two agricultural fields under tomatoes (Lycopersicon esculentum). The two fields, located in the California Central Valley, had either a history of high organic matter (OM) inputs ("organic" management) or one of low OM and inorganic fertilizer inputs ("conventional" management). In microcosms, where short-term microbial responses to wetting and drying were studied, the highest CO2 efflux took place at about 60% water-filled pore space (WFPS). At this moisture level, phospholipid fatty acids (PLFA) indicative of microbial nutrient availability were elevated and a PLFA stress indicator was depressed, suggesting peak microbial activity. The highest N 2 O efflux in the organically managed soil (0.94 mg N2 O-N m-2 h-1 ) occurred after manure and legume cover crop 266 SYNOPTIC GEOGRAPHY incorporation, and in the conventionally managed soil (2.12 mg N2 O-N m-2 h-1 ) after inorganic N fertilizer inputs. Elevated N2 O emissions occurred at a WFPS >60% and lasted <2 days after wetting, probably because the top layer (0-150 mm) of this silt loam soil dried quickly. Therefore, in these cropping systems, irrigation management might control the duration of elevated N2 O efflux, even when C and inorganic N availability are high, whereas inorganic N concentrations should be kept low during times when soil moisture cannot be controlled. 1407 Methane release through resuspension of littoral sediment Bussmann I. Biogeochemistry 2005 74/3 (283-302) Sediment in the littoral zone of lakes is frequently disturbed by wave action or bioturbation, resulting in sediment resuspension. In undisturbed sediment, methanotrophic bacteria efficiently reduce the diffusive flux of methane into the water column. In a microcosm study, the resuspension of littoral sediment was simulated in sediment cores for a winter (n = 3) and a summer situation (n = 3). The erosion of surface sediment resulted in a large flux of methane into the overlying water (207 176 mol h -1 m-2 in winter and 73 18 mol h-1 m-2 in summer). Only a minor part (16 7%) of the methane released was oxidized by methanotrophic bacteria, whereas the major part escaped into the water column. Only 6-16% of the littoral zone has to be resuspended to reach the same flux as from undisturbed littoral sediment. For the daily flux, a sediment resuspension has to last 1-4 h to reach the undisturbed daily flux. The study reveals the important role of sediment resuspension in the littoral methane cycle as an intense but variable source of methane of largely unknown magnitude. © Springer 2005. 1408 Short-term effects of clearfelling on soil CO2 , CH4 , and N2 O fluxes in a Sitka spruce plantation Zerva A. and Mencuccini M. Soil Biology and Biochemistry 2005 37/11 (2025-2036) We examined the effects of forest clearfelling on the fluxes of soil CO2 , CH4 , and N2 O in a Sitka spruce (Picea sitchensis (Bong.) Carr.) plantation on an organic-rich peaty gley soil, in Northern England. Soil CO2 , CH4 , N2 O as well as environmental factors such as soil temperature, soil water content, and depth to the water table were recorded in two mature stands for one growing season, at the end of which one of the two stands was felled and one was left as control. Monitoring of the same parameters continued thereafter for a second growing season. For the first 10 months after clearfelling, there was a significant decrease in soil CO2 efflux, with an average efflux rate of 4.0 g m-2 d-1 in the mature stand (40-year) and 2.7 g m -2 d-1 in clearfelled site (CF). Clearfelling turned the soil from a sink (-0.37 mg m-2 d-1 ) for CH4 to a net source (2.01 mg m-2 d-1 ). For the same period, soil N2 O fluxes averaged 0.57 mg m-2 d-1 in the CF and 0.23 mg m-2 d-1 in the 40-year stand. Clearfelling affected environmental factors and lead to higher daily soil temperatures during the summer period, while it caused an increase in the soil water content and a rise in the water table depth. Despite clearfelling, CO2 remained the dominant greenhouse gas in terms of its greenhouse warming potential. © 2005 Elsevier Ltd. All rights reserved. 1409 Pan-European 13 C values of air and organic matter from forest ecosystems Hemming D., Yakir D., Ambus P. et al. Global Change Biology 2005 11/7 (1065-1093) We present carbon stable isotope, 13 C, results from air and organic matter samples collected during 98 individual field campaigns across a network of Carboeuroflux forest sites in 2001 (14 sites) and 2002 (16 sites). Using these data, we tested the hypothesis that 13 C values derived from large-scale atmospheric measurements and models, which are routinely used to partition carbon fluxes between land and ocean, and potentially between respiration and photosynthesis on land, are consistent with directly measured ecosystem-scale 13 C values. In this framework, we also tested the potential of 13 C in canopy air and plant organic matter to record regional-scale ecophysiological patterns. Our network estimates for the mean 13 C of ecosystem respired CO2 and the related ‘discrimination’ of ecosystem respiration, 1.9‰ and 17.8 2.0‰ er and er respectively, were -25.6 in 2001 and -26.6 1.5‰ and 19.0 1.6‰ in 2002. The results were in close agreement with 13 C values derived from regional-scale atmospheric measurement programs for 2001, but less so in 2002, which had an unusual precipitation pattern. This suggests that regional-scale atmospheric sampling programs generally capture ecosystem 13 C signals over Europe, but may be limited in capturing some of the interannual variations. In 2001, but less so in 2002, there were discernable longitudinal and seasonal trends in er From west to east, across the network, there was a general enrichment in 13 C ( 3‰ and l‰ for the 2 years, respectively) consistent with increasing Gorczynski continentality index for warmer and drier conditions. In 2001 only, seasonal 13 C enrichment between July and September, followed by depletion in November (from about -26.0‰ to -24,5‰ to 30.0‰), was also observed. In 2001, July and August er values across the network were significantly related to average daytime vapor pressure deficit (VPD), relative humidity (RH), and, to a lesser degree, air temperature (Ta ), but not significantly with monthly average precipitation (Pm ). In contrast, in 2002 (a much wetter peak season), er was significantly related with Ta , but not significantly with VPD and RH. The important role of plant physiological processes on er in 2001 was emphasized by a relatively rapid turnover (between 1 and 6 days) of assimilated carbon inferred from time-lag analyses of er vs. meteorological parameters. However, this was not evident in 2002. These analyses also noted corresponding diurnal cycles of er and meteorological parameters in 2001, indicating a rapid transmission of daytime meteorology, via physiological responses, to the er signal during this season. Organic matter 13 C results showed progressive 13 C enrichment from leaves, through stems and roots to soil organic matter, which may be explained by 13 C fractionation during respiration. This enrichment was species dependent and was prominent in angiosperms but not in gymnosperms. 13 C values of organic matter of any of the plant components did not well represent short-term er values during the seasonal cycle, and could not be used to partition ecosystem respiration into autotrophic and heterotrophic components. © 2005 Blackwell Publishing Ltd. 1410 Statistical analysis of the major variables controlling methane emission from rice fields Yan X., Yagi K., Akiyama H. and Akimoto H. Global Change Biology 2005 11/7 (1131-1141) Rice cultivation is an important anthropogenic source of atmospheric methane (CH4 ), the emission of which is affected by management practices. Many field measurements have been conducted in major rice-producing countries in Asia. We compiled a database of CH4 emissions from rice fields in Asia from peer-reviewed journals. We developed a statistical model to relate CH4 flux in the rice-growing season to soil properties, water regime in the rice-growing season, water status in the previous season, organic amendment and climate. The statistical results showed that all these variables significantly affected CH4 flux, and explained 68% of the variability. Organic amendment and water regime in the rice-growing season were the top two controlling variables; climate was the least critical variable. The average CH4 fluxes from rice fields with single and multiple drainages were 60% and 52% of that from continuously flooded rice fields. The flux from fields that were flooded in the previous season was 2.8 times that from fields previously drained for a long season and 1.9 times that from fields previously drained for a short season. In contrast to the previously reported optimum soil pH of around neutrality, soils with pH of 5.0-5.5 gave the maximum CH4 emission. The model results demonstrate that application of rice straw at 6tha-1 before rice transplanting can increase CH4 emission by 2.1 times; when applied in the previous season, however, it increases CH4 emission by only 0.8 times. Default emission factors and scaling factors for different water regimes and organic amendments derived from this work can be used to develop national or regional emission inventories. © 2005 Blackwell Publishing Ltd. 1411 Soil CN ratio as a scalar parameter to predict nitrous oxide emissions Klemedtsson L., Von Arnold K., Weslien P. and Gundersen P. Global Change Biology 2005 11/7 (1142-1147) Forested histosols have been found in some cases to be major, and in other cases minor, sources of the greenhouse gas nitrous oxide LANDFORMS (N2 O). In order to estimate the total national or global emissions of N2 O from histosols, scaling or mapping parameters that can separate low- and high-emitting sites are needed, and should be included in soil databases. Based on interannual measurements of N2 O emissions from drained forested histosols in Sweden, we found a strong negative relationship between N 2 O emissions and soil CN ratios (r2adj = 0.96, mean annual N2 O emission = (-bCNratio) ). ae The same equation could be used to estimate the N2 O emissions from Finnish and German sites based on CN ratios in published data. We envisage that the correlation between N2 O emissions and CN ratios could be used to scale N2 O emissions from histosols determined at sampled sites to national levels. However, at low CN ratios (i.e. below 15-20) other parameters such as climate, pH and groundwater tables increase in importance as regulating factors affecting N2 O emissions. © 2005 Blackwell Publishing Ltd. LANDFORMS Weathering and related landforms 1412 Climatic control on clay mineral formation: Evidence from weathering profiles developed on either side of the Western Ghats Deepthy R. and Balakrishnan S. Proceedings of the Indian Academy of Sciences, Earth and Planetary Sciences 2005 114/5 (545-556) Many physico-chemical variables like rock-type, climate, topography and exposure age affect weathering environments. In the present study, an attempt is made to understand how the nature of clay minerals formed due to weathering differs in tropical regions receiving high and low rainfall. Clay mineralogy of weathering profiles in west coast of India, which receives about 3 m rainfall through two monsoons and those from the inland rain-shadow zones (< 200 cm rainfall) are studied using X-ray diffraction technique. In the west coast, 1:1 clays (kaolinite) and Fe-Al oxides (gibbsite/goethite) are dominant clay minerals in the,weathering profiles while 2:1 clay minerals are absent or found only in trace amounts. Weathering profiles in the rain shadow region have more complex clay mineralogy and are dominated by 2:1 clays and kaolinite, Fe-Al oxides axe either less or absent in clay fraction. The kaolinite-smectite interstratified mineral in Banasandra profiles are formed due to transformation of smectites to kaolinite, which is indicative of a humid paleoclimate. In tropical regions receiving high rainfall the clay mineral assemblage remains the same irrespective of the parent rock type. Rainfall and availability of water apart from temperature, are the most important factors that determine kinetics of chemical weathering. Mineral alteration reactions proceed through different pathways in water rich and water poor environments. © Printed in India. Fluvial landforms 1413 Geomorphology and American dams: The scientific, social, and economic context Graf W.L. Geomorphology 2005 71/1-2 (3-26) American geomorphologic research related to dams is embedded in a complicated context of science, policy, economics, and culture. Research into the downstream effects of large dams has progressed to the point of theory-building, but generalization and theory-building are from this research because (1) it is highly focused on a few locations, (2) it concerns mostly very large dams rather than a representative sample of sizes, (3) the available record of effects is too short to inform us on long-term changes, (4) the reversibility of changes imposed by dam installation and operation is unknown, and (5) coordinated funding for the needed research is scarce. In the scientific context, present research is embedded in a history of geomorphology in government service, with indistinct boundaries between "basic and applied" research. The federal policy that most strongly influences present geomorphological investigations connected with dams is related to 267 habitat for endangered species, because the biological aspects of ecosystems are directly dependent on the substrate formed by the sediments and landforms that are influenced by dams. The economic context for research includes large amounts of public funds for river restoration, along with substantial private investments in dams; and geomorphology is central to these expensive issues. The cultural context for research is highly contentious and dominated by advocacy procedures that include intense scrutiny of any geomorphologic research related to dams. Advocates are likely to use the products of geomorphological research to make cases for their own positions. © 2005 Elsevier B.V. All rights reserved. 1414 Dams and geomorphology: Research progress and future directions Petts G.E. and Gurnell A.M. Geomorphology 2005 71/1-2 (2747) Dams impose changes of flow and sediment transfer that drive changes of channel form along the downstream regulated river. These changes have been described for more than 50 years but process-form relationships have only been advanced with the establishment of a conceptual framework during the 1970s, and then the extension of monitoring data and advancement of remote sensing technologies, particularly over the past 20 years. This paper reviews these developments and identifies three influential themes: (i) channel dynamics, (ii) the role of riparian vegetation, and (iii) channel change as the driver of ecological change. Changes can be rapid in semi-arid regions but elsewhere relaxation periods may extend to millenia. In these latter cases regime or steady-state models should be replaced by models of transient states applied to the reach scale in order to respond to the needs of river managers over decadal timescales. © 2005 Elsevier B.V. All rights reserved. 1415 The geomorphic influences of beaver dams and failures of beaver dams Butler D.R. and Malanson G.P. Geomorphology 2005 71/1-2 (48-60) Uncounted millions of beaver ponds and dams existed in North America prior to European contact and colonization. These ponds acted as sediment traps that contained tens to hundreds of billions of cubic meters of sediment that would otherwise have passed through the fluvial system. Removal of beavers by overtrapping in the 16th-19th centuries severely reduced their number and the number of ponds and dams. Dam removal altered the fluvial landscape of North America, inducing sediment evacuation and entrenchment in concert with widespread reduction in the wetlands environments. Partial recovery of beaver populations in the 20th century has allowed reoccupation of the entirety of the pre-contact range, but at densities of only onetenth the numbers. Nevertheless, modern beaver ponds also trap large volumes of sediment in the high hundred millions to low billions of cubic meters range. Failure of beaver dams is a more common phenomenon than often as sumed in the literature. During the past 20 years, numerous cases of dam failure have been documented that resulted in outburst floods. These floods have been responsible for 13 deaths and numerous injuries, including significant impacts on railway lines. © 2005 Elsevier B.V. All rights reserved. 1416 Effects of Jackson Lake Dam on the Snake River and its floodplain, Grand Teton National Park, Wyoming, USA Marston R.A., Mills J.D., Wrazien D.R. et al. Geomorphology 2005 71/1-2 (79-98) In 1906, the Bureau of Reclamation created Jackson Lake Dam on the Snake River in what later became Grand Teton National Park. The geomorphic, hydrologic and vegetation adjustments downstream of the dam have yet to be documented. After a larger reservoir was completed further downstream in 1957, the reservoir release schedule from Jackson Lake Dam was changed in a manner that lowered the magnitude and frequency of floods. The stability of the Snake River exhibited a complex response to the change in flow regime. Close to major tributaries, the Snake River increased in total sinuosity and rates of lateral channel migration. Away from the influence of tributaries, the river experienced fewer avulsions and a decrease in sinuosity. Vegetation 268 LANDFORMS maps were constructed from 1945 and 1989 aerial photography and field surveys. Using these data, we determined how vegetation is directly related to the number of years since each portion of the floodplain was last occupied by the channel. The vegetation has changed from a flood-pulse dominated mosaic to a more terrestrial-like pattern of succession. Changes in the Snake River and its floodplain have direct implications on bald eagle habitat, moose habitat, fish habitat, safety of rafting and canoeing, and biodiversity at the community and species levels. © 2005 Elsevier B.V. All rights reserved. 1417 Floodplain-river ecosystems: Fragmentation and water resources development Thoms M.C., Southwell M. and McGinness H.M. Geomorphology 2005 71/1-2 (126-138) Floodplain-river ecosystems are natural fragmented systems because of periodic hydrological connections. The integrity of these ecosystems is thought to be dependent, in part, upon exchanges of energy and matter between patches, such as the main river channel, adjacent floodplain surface and other morphological features, during periods of connection. Flow regulation and its associated infrastructure change the natural character of fragmentation in floodplain-river ecosystems, and have important consequences for their overall productivity. This paper considers the influence of water resources development on the character of fragmentation in a large lowland river in SE Australia. Largescale water resources development in the Macintyre River, Australia, has significantly altered the spatial and temporal patterns of hydrological connections. The construction of weirs and other embankments on the lower Macintyre River floodplain prevents water movement through a series of anabranch channels thereby reducing the availability of these floodplain patches by 55%. In addition, because of flow regulation, hydrological connections to these channels occur up to 22% less often. Data are presented showing the impacts of these changes on the potential supply of dissolved organic carbon from the anabranch channels during periods of inundation over a 98-year period. Reductions of up to 98% of potential dissolved organic carbon supply from some anabranch channels were noted. © 2005 Elsevier B.V. All rights reserved. 1418 Statistical analysis of lateral migration of the Rio Grande, New Mexico Richard G.A., Julien P.Y. and Baird D.C. Geomorphology 2005 71/1-2 (139-155) The lateral migration rates of alluvial rivers are affected by changes in water and sediment regimes. The Rio Grande downstream from Cochiti Dam exhibits spatial and temporal variability in lateral movement rates documented since 1918. A tremendous database exists that documents planform, bed material size, channel geometry, and water and sediment regimes. A statistical analysis reveals that migration rates primarily decreased with decreasing flow energy (R2 > 0.50, p < 0.0001). The addition of a second parameter describing total channel width increased the explained variance to > 60%. The findings show that lateral movement increases with increasing flow energy and with degree of braiding. © 2005 Elsevier B.V. All rights reserved. 1419 Equilibrium or indeterminate? Where sediment budgets fail: Sediment mass balance and adjustment of channel form, Green River downstream from Flaming Gorge Dam, Utah and Colorado Grams P.E. and Schmidt J.C. Geomorphology 2005 71/1-2 (156181) This study examines bed and bank adjustment in the 105-km reach of the Green River immediately downstream from Flaming Gorge Dam by the use of historical aerial and oblique photographs, analysis of current and abandoned stream-gaging records, and field observations. Although this segment has been previously characterized as sediment deficient, these data show that sediment is accumulating in all reaches and that the bed has not degraded at any location where historical data are available. Adjustment is occurring through a combination of deposition of post-dam sediment and stabilization of pre-dam deposits, resulting in a 10-30% reduction in average width of the channel. All post-dam surfaces are colonized by woody riparian vegetation. The style of channel adjustment varies between geomorphically defined reaches. In canyons dominated by debris fans and gravelbedded restricted meandering reaches, gravel bars have become inactive and accumulated fine sediment. In the sand-bedded meandering reaches, existing islands have increased in size and new mid-channel islands have formed. In all of these types of reaches, post-dam deposits line the banks and sediment has accumulated in side-channels that previously separated islands from the bank. These findings demonstrate that sediment budgets that show a balance between inputs and outputs cannot necessarily be interpreted to indicate channel equilibrium. A sediment mass balance for 150-km reach between the dam and the first long-term gage indicates approximate balance of inputs and outputs for the pre- and post-dam periods. When uncertainty in budget components is considered, the mass balance is indeterminate. Although the Green River may have been in approximate equilibrium in the pre-dam period, we have shown that channel width is decreasing in the post-dam period. The post-dam deposits constitute a small but a significant component of the sediment budget upstream from the first major tributary. Sediment is supplied to this reach by small tributaries and, to a lesser extent, erosion of pre-dam alluvium. Downstream from the study area, the volume of the post-dam deposits is tiny relative to the volume of sediment input from the first major tributary. © 2005 Elsevier B.V. All rights reserved. 1420 Potential sedimentation impacts related to dam removal: Icicle Creek, Washington, U.S.A Lorang M.S. and Aggett G. Geomorphology 2005 71/1-2 (182201) A series of small dams were built in Icicle Creek in 1937 to facilitate the operations of Leavenworth National Fish Hatchery. However, several of those dams have been abandoned spurring recent discussions among local watershed conservation groups, as well as state and federal agencies, about removing the dams and the potential impact to the lower reaches of Icicle Creek due to elevated sedimentation. The objective of this study was to measure the total volume of sediment trapped behind the Icicle Creek dams and estimate the potential sedimentation impacts for the lower portion of Icicle Creek should the dams be removed. Another objective was to assess the ability of the river to flush the sediments and naturally restore the system to as close to its predam condition as possible. A flow-competence approach was used to assess the restoration potential of the river to do the work of flushing sediments and reestablishing the predam stream channel characteristics. A sediment probe, a total station, a GPS and aerial photographs were used to map out sediment deposits and measure their depths to determine sediment volumes. Grain size distributions from bed sediments, bars, islands and stream banks were used to assess potential downstream sedimentation impacts. The total volume of sediment trapped behind the dams was estimated at 36,000 m3 ( 4000 m3 ). The river has sufficient stream power to flush these sediments over 90% of its natural discharge regime. Controlled flushing of the trapped sediments over several years poses very little threat to the water quality and spawning habitats in the lower Icicle Creek scaled against natural flux rates. © 2005 Elsevier B.V. All rights reserved. 1421 The evolution of gravel bed channels after dam removal: Case study of the Anaconda and Union City Dam removals Wildman L.A.S. and MacBroom J.G. Geomorphology 2005 71/12 (245-262) The Anaconda and Union City Dams on the Naugatuck River in Connecticut were removed in February and October 1999. A detailed study of the sites prior to removal was undertaken including sediment testing and predictions of upstream channel formation post-dam removal. The 3.35-m-high timber crib/rock fill spillway of the Anaconda Dam partially breached during a storm prior to the dam’s scheduled removal allowing a portion of the impounded sediment to move down through the river system. This event changed the removal plans and the remainder of the spillway was removed under an emergency order in the course of 4 days. The Union City Dam, a 2.44-m-high timber crib/rock fill dam capped with concrete and stone, was removed on schedule. A portion of the impounded sediment was removed by mechanical means during the deconstruction of the structure. LANDFORMS The evolution of the two upstream channels post-project provided unique challenges and valuable insights as to what kind of channel transition can be expected in gravel bed river systems after a low head dam has been removed. This paper describes the initial engineering analysis and design, the subsequent removal of the two dams, and compares observations on the transition of the upstream channels following dam removal to the initial engineering predictions and other models. The relatively steep gravel bed channels evolved in a predictable manner, except where anthropogenic barriers (sanitary sewer, rock weir) interrupted. © 2005 Elsevier B.V. All rights reserved. 1422 Riverine landscape and geomorphology: Ecological implications and river management strategy Lehotsk´y M. and Greˇskov´a A. Ekologia Bratislava 2004 23/SUPPL. 1 (179-190) Traditionally, geographers and landscape ecologists have focused their attention on terrestrial systems (in Slovakia LANDEP, landscape potencial approach are examples) and rivers have been considered either as elements of landscape pattern as biocorridors or as units that are linked to the terrestrial landscape by flows across boundaries. We present the methodology of riverine landscape with accent to its geomorphic base. The concept of river connectivity and river continuum, hierarchy, flood-pulse and related telescoping concepts as well as channel sensitivity and natural capital value concepts are discussed. 1423 Case study: Modeling the lateral mobility of the Rio Grande below Cochiti dam, New Mexico Richard G.A., Julien P.Y. and Baird D.C. Journal of Hydraulic Engineering 2005 131/11 (931-941) The Cochiti reach of the Rio Grande served as a case study to test the hypothesis that the lateral mobility of an alluvial river decreases as the river approaches equilibrium. The lateral mobility of the river was measured using a geographic information system from digitized aerial photographs of the nonvegetated active channel between 1918 and 2001. Reach-averaged lateral mobility was quantified in terms of width change, lateral migration, and total lateral movement. By 2001, the width of the Cochiti Reach was close to the expected equilibrium width indicating that the river had adjusted to the incoming water and sediment load. An exponential equation based on deviation from equilibrium width described 95-96% of the variance in channel width, 7890% of variance in migration rates, and 92% of the variance in total lateral movement between 1918 and 1992. For validation of the model, the 2001 width and migration rates were predicted with errors as low as 19 and 8%, respectively. The exponential width model was also appliedto four other rivers that exhibited narrowing trends following dam construction and explained 8289% of the variance in width change on those rivers. Journal of Hydraulic Engineering © ASCE. 1424 Regional patterns of salt lake morphology in the lower Yarra Yarra drainage system of Western Australia Boggs D.A., Boggs G.S., Eliot I. and Knott B. Journal of Arid Environments 2006 64/1 (97-115) This paper examines the spatial variation of salt lake morphology in the lower Yarra Yarra drainage system of Western Australia. Shape, size (length and area), orientation and density of 4500 salt lakes were measured. Two main morphological groups were distinguished: small (<10 ha), elliptical to circular playas with a NNW-SSE orientation; and large (>30 ha), elongated playas. Intra-system variability in morphologic characteristics was notable. Regional patterns in lake size, shape and density distribution were markedly different between the west and east sides of the system. The boundary between the two sides coincides approximately with rainfall distribution. The Morawa sub-division in the west of the region was morphologically different from the remainder of the lower lacustrine system in that it had a predominance of small, elliptical playas and lacked a major playa. It was postulated that lake segmentation processes have been enhanced in this part of the system through a combination of local climate variation, the near-parallel orientation of the thalweg of the drainage system axis relative to prevailing winds, with possible topographical relief and geological influences. © 2005 Elsevier Ltd. All rights reserved. 269 1425 The Oxaya anticline (northern Chile): A buckle enhanced by river incision? Zeilinger G., Schlunegger F. and Simpson G. Terra Nova 2005 17/4 (368-375) A prominent structure in the Western Escarpment of the Andes of northern Chile is the Oxaya anticline, dissected at the culmination by >1500 m deep valleys. The distribution of fault and fold structures indicates that the anticline could represent a simple buckle. Buckling thus appears to have accommodated crustal shortening in the plate overriding the subducting plate, between the trench and the Western Cordillera. Cross-cutting relationships between structures and dated strata indicated that the time interval of enhanced buckling coincides with the period when rates of valley formation were enhanced. We thus propose that the formation of this anticline was enhanced by fluvial incision, which is consistent with the results of published theoretical models. © 2005 Blackwell Publishing Ltd. 1426 Recession rates of waterfalls in and upstream of the Tateno canyon, Aso volcano (Japanese) Hayakawa Y.S., Yokoyama S. and Matsukura Y. Chikei/Transactions, Japanese Geomorphological Union 2005 26/4 (439-449) Recession rates of two waterfalls, Ayugaeri Falls and Sugaru Falls, which are associated with the gorge formation of in the Tateno Canyon in the western part of the Aso caldera, are examined on the basis of the empirical equation after Hayakawa and Matsukura (2003). The waterfalls are postulated to have originated at a location out of the caldera as a waterfall which was formed around the front of the Akase lava erupted from the inside of the caldera. The initial waterfall receded about 2.8 km upstream forming the gorge to the present site of the confluence of the Shirakawa River and the Kurokawa River in the caldera. At the confluence, the waterfall bifurcated into two waterfalls which continued recession along the Shirakawa River and the Kurokawa River to the present locations of the Ayugaeri and Sugaru falls. The recession rates estimated from the equation are 0.086 m/y for Ayugaeri Falls and 0. 143 m/y for Sugaru Falls. The calculated time taken for the recession from the confluence to the present sites of the individual waterfalls is nearly equal: ca. 13,000 y, indicating that the bifurcation of the waterfalls occurred about 13,000 years ago. Rough estimation suggests that the time for the initial waterfall to recede the distance of 2.8 km is 14,00028,000 y, The total time of the waterfall recession from the start to the present location is thus 27,000-41,000 y, which is consistent with the age of the Akase lava flow (ca. 30,000 y). 1427 Gandak fan - A macro quaternary feature of middle Ganga plain, Uttar Pradesh and Bihar Prasad S. and Khan E.A. Journal of the Geological Society of India 2005 65/5 (597-608) Gandak fan, is a large lobate feature trending in NW-SE direction, restricted between the fluvial regimes of Little Gandak in the west and Burhi Gandak in the east, in parts of eastern Uttar Pradesh and north Bihar. It is characterised by distinct geomorphology, manifested by clusters of tals, palaeochannels, oxbow lakes and spill over channels left out by a past history of river migration and flash floods of Gandak and its predecessors. The terrain is characterised by wide spread drapes of newer alluvium sediments locally known as Bhat Alluvium forming a calcareous, fine sandy to silty soil. Granulometric properties of the sand sequence associated with this unit indicate dominance of very fine grained sand with median value of 3.0 phi. The clay mineral study of this soil unit indicates preponderance of calcite mineral (30%) besides illite, chlorite and muscovite. Based on the analysis and synthesis of data, an attempt has been made to interpret the morphology of Gandak fan and the genesis of widespread occurrences of Bhat Alluvium of this region. The model envisaged for the formation of the fan dwells on possible cataclasmic neotectonic events related to Gandak Tear and other structures in the vicinity. The neotectonic event triggered widespread river migration/avulsion and cascades of mud flows released from breach and spill over of some large lacustrine bodies formed earlier by damming of the river course in the Jhawani Valley in upstream of Gandak catchment area in Nepal. In addition, the geological and geomorphological set up of Gandak Fan has also 270 LANDFORMS relevance to environmental scenario of the area especially to the perpetual floods in large tracts of north Bihar. It is also surmised th at the cascades of mudflows related in the formation of fan and rampant floods in the area might be the causative factors for burial of many important temples and monasteries of Buddhist period, such as Kushinagar, Vaishali, Lauria, etc. © Geol. Soc. India. Coastal landforms 1428 Phytolith assemblages as indicators of coastal environmental changes and hurricane overwash deposition Lu H.- Y. and Liu K.- B. Holocene 2005 15/7 (965-972) We demonstrate that phytolith assemblages are a useful proxy for reconstructing coastal environmental changes and for validating the overwash origin of sand layers in palaeotempestology studies. Phytolith analysis was conducted on 50 topsoil or surface sediment samples collected from a variety of coastal plant communities or depositional environments in the southeastern USA. The data suggest that different coastal subenvironments can be distinguished by their modern phytolith assemblages. For example, coastal marsh samples contain a diverse phytolith assemblage dominated by smooth-elongate and square morpho-types and maritime forest samples are dominated by phytoliths from palms and broadleaf dicotyledonous plants. Remarkably, the phytolith assemblages from sand dunes are characterized by high percentages of two-horned-tower, flat-tower, spool/horned-tower and short-saddle types. Phytolith analysis of three prehistoric sand layers in a sediment core from Western Lake, northwestern Florida, shows that they contain a phytolith assemblage similar to those characteristic of sand dunes and interdune meadows. These observations are confirmed by the results of principal components analysis and discriminant analysis on the modern and fossil phytolith data sets. Our study results support the interpretation that the sand layers in Western Lake were indeed formed by the erosion of sand dunes during overwash processes caused by landfalling catastrophic hurricanes. © 2005 Edward Arnold (Publishers) Ltd. 1429 Persistence of storm-induced morphology on a modal low-energy beach: A case study from NW-Iberian Peninsula Costas S., Alejo I., Vila- Concejo A. and Nombela M.A. Marine Geology 2005 224/1-4 (43-56) The morphology of low-energy beaches is inherited from highenergy events showing a non equilibrium state with the prevailing conditions. An example of a sheltered, low-energy beach (Rodas Beach, NW-Iberian Peninsula) is examined in this paper. The evolution of six beach profiles was analysed during three years in order to investigate the response of this beach under fair-weather and storm conditions. The beach presented significant morphological differences alongshore due to its geographical location with respect to the wave approach. These differences determined the sediment transfer pattern (longshore or cross-shore sediment transport) from the emerged beach towards the adjacent inner shoreface zone. Significant morphological changes at each profile seem to be related to the incidence of sea waves along the beach superimposed on persistent swell during winter. Morphological changes were recorded under high-energy storms, during winter, whereas the recovery to prestorm conditions occurred under prevailing fair weather conditions, during summer. The traditional beach classification parameter Relative Tidal Range (RTR), which takes into account the effect of the tide range, was found unsuitable to properly classify such a mesotidal low-energy beach. Therefore, a new parameter, the Relative Tidal Range Maximum (RTRmax) was introduced, which is a modification of the commonly used RTR. RTRmax uses the highest wave breaking height, observed during high-energy storm conditions, instead of the modal wave breaking height. By using this parameter, the studied beach could be properly classified into the traditional beach classification models taking into account the tide range. Since low-energy beaches generally show a morphology that is inherited from higher energy conditions than the prevailing conditions, it is expected that the RTRmax will be applicable for the classification of other low-energy sheltered beaches. © 2005 Elsevier B.V. All rights reserved. 1430 Barrier formation on an actively prograding delta system: The Red River Delta, Vietnam Van Maren D.S. Marine Geology 2005 224/1-4 (123-143) An extensive barrier-spit system 20 to 30 km long developed on the delta front platform of the Ba lat Delta within a relatively short period (10-20 years). However, it was not evident whether the formation was related to river floods, typhoons or calm weather conditions, or to cross-shore or alongshore sediment transport mechanisms. Therefore a process-based numerical model that simulates sediment transport and morphologic changes by waves, tides, wind, and river flow, is used to analyze the processes that govern this barrier formation. The mechanism that initiates the barrier formation is concluded to be onshore transport by wave asymmetry of sediment previously transported seaward in the buoyant river plume. The main mechanism that counteracts the barrier formation is probably destruction of the barrier by river flow. During the subsequent transformation from a subaqueous barrier into a sub-aerial barrier-spit system, overwashes and alongshore sediment transport become increasingly important. This spit system therefore appears to be dominated by alongshore processes, even though its initial formation is more strongly regulated by cross-shore processes. The importance of cross-shore processes results in a minor contribution of typhoons to the initial formation of these barriers. Typhoons are not very important to destruction of barriers as well, because wave energy is gradually dissipated over the gentle offshore profile, which in turn results from river plume sedimentation. © 2005 Elsevier B.V. All rights reserved. 1431 Fetch limited barrier islands of Chesapeake Bay and Delaware Bay Lewis D.A., Cooper J.A.G. and Pilkey O.H. Southeastern Geology 2005 44/1 (1-17) Barrier islands within bays, lagoons, estuaries and other protected waters have never been the subject of systematic research on a large scale. Within both the Chesapeake and Delaware Bays, barrier islands are numerous and widely distributed. Totaling more than 300 in number, these fetch limited barrier islands exhibit a range of morphologies uncommon along open ocean shorelines. We group the barrier islands in the two bays into three primary categories based on their morphology and location. In general, they are much shorter (km), narrower (<25m), and lower (1-2m) than their open ocean analogs, yet they behave in much the same way in their response to oceanographic processes. The greatest difference between ocean and bay barriers is the strong control of evolutionary processes by vegetation, usually salt marsh, in the bays. 1432 The impact of Hurricane Georges (September 28, 1998) across Dauphin Island, Alabama Froede Jr. C.R. Southeastern Geology 2005 44/1 (45-51) On the morning of September 28, 1998, Hurricane Georges (a Category 2 hurricane on the Saffir-Simpson scale) made landfall between the towns of Ocean Springs and Biloxi, Mississippi. Passing well to the west of Dauphin Island, the storm still impacted the island with wind speeds up to 129 km/hr (a Category 1 hurricane on the Saffir-Simpson scale). This resulted in substantial changes along the island’s gulf side. The eastern end of the island experienced a storm surge along with accompanying storm waves that easily overtopped the swash zone berm crest. Storm waves washed tens of meters landward and flattened the beach profile. Much of the western end of the island was completely overwashed by storm waves. As of early 2005, natural shoreline processes have not restored the pre-storm beach profile or returned the swash zone to its former position. Tropical storms and hurricanes that impact the island reveal its vulnerability and dependence on regular sand nourishment. Hurricane Georges exposed the fragile nature and precarious setting of Dauphin Island in the Gulf of Mexico. LANDFORMS 1433 Contribution of simulations on historical bathymetries to the understanding of evolutions of estuarine sand banks (French) (Apports de la mod´elisation sur bathym´etries historiques dans la compr´ehension des e´ volutions des bancs de sable estuariens) Bertin X. and Chaumillon E. Comptes Rendus - Geoscience 2005 337/15 (1375-1383) Formation and evolution of estuarine sand ridges are some of the less well known among the different classes of sand banks. Simulation of tides and related sand bedload transport on historical bathymetries brings new insights about the secular evolution of two estuarine sand ridges (the Saint-Georges and the ‘Longe de Boyard’ sand banks, Atlantic coast of France). Two different mechanisms are involved in order to explain the evolutions of these banks, suggesting the category of estuarine sand banks to be less homogenous than it is proposed in the last classifications of sand banks. © 2005 Acad´emie des sciences. Publi´e par Elservier SAS. Tous droits r´eserv´es. Arid landforms 1434 Preliminary assessment of sand dune stability along a bioclimatic gradient, North-Central and Northwestern Oklahoma Cordova C.E., Porter J.C., Lepper K. et al. Great Plains Research 2005 15/2 (227-249) Sandhills of eolian origin and currently active dunes in Oklahoma are located mainly on the northern side of the main rivers. Their longitudinal distribution spans a gradient of annual precipitation ranging from 914 mm in the east to 403 mm in the west. Vegetation types along this gradient include cross-timbers woodlands in the east and sand-sage and short grasses in the west. The information presented here is a preliminary assessment of sand dune dynamics and morphology, soils, and vegetation as the basis for an ongoing study on past and present processes of sand dune stability. For this purpose, six areas along the east-west precipitation gradient were selected to evaluate potential sources of information. Pedostratigraphic data were used to reconstruct prehistoric landscape-change events and sequential aerial photographs were used to reconstruct modern processes affecting sand dune stability in the context of climate change and human agency. © Copyright by the Center for Great Plains Studies, University of Nebraska-Lincoln. 1435 Aeolian sand depositional records from Western Nebraska: Landscape response to droughts in the past 1500 years Forman S.L., Marn L., Pierson J. et al. Holocene 2005 15/7 (973-981) The Great Plains is dominated by presently stabilized dune fields that are indicators of extreme drought in the late Holocene. This study focused on deciphering the timing of reactivation of dunes in western Nebraska. Stratigraphy adjacent to dune-dammed lakes reveals aeolian sand separated by palaeosols, indicating mobilization of aeolian sand followed by landscape stability. The chronology of aeolian-sand depositional events is constrained using the luminescence-based, single aliquot regeneration method, providing resolution to relate dune movement to tree-ring and palaeolimnologic records of drought. There are at least a six aeolian depositional events in the past 1500 years, with apparent mean ages of 1390 130, 670 70, 470 40, 240 40, 140 20 and 70 10 yr. All study sites show evidence for aeolian accumulation in the twentieth century, potentially reflecting the 1930s drought. Significant aeolian activity is coincident with the tree-ring-identified sixteenth-century megadrought, indicating widespread landscape impacts. © 2005 Edward Arnold (Publishers) Ltd. 1436 Late Pleistocene eolian history of the Liwa region, Arabian Peninsula Stokes S. and Bray H.E. Bulletin of the Geological Society of America 2005 117/11-12 (1466-1480) The Liwa region of the United Arab Emirates is one of the most distinctive geomorphological features of the Rub Al Khali desert of southern Arabia. Characterized by a sharp crescentic boundary 271 coincident with a N-S elevation drop of 65 m with the transverse ridges in Al Qˆafa to the north, Liwa is an area of some of the world’s largest megabarchan dunes. Deep drilling of continuous cores has provided an opportunity to observe the internal structure and age of these two ergs. Subsurface stratigraphy is complex, reflecting rapid facies transitions between dune and interdune sub-environments. Most of the cored sediment is dominated by cross-bedded and structureless sand units of inferred eolian (transverse dune) depositional origin. A total of 56 optical ages for sand-sized quartz grains extracted from these cores provide a chronological framework for deposition of the late Quaternary ergs. A marine isotope stage (MIS) 5 erg is identified north of the Liwa crescent in the Al Qˆafa region, which reaches vertical thicknesses >100 m. A MIS 1 erg in the form of megabarchan dunes is recorded south of the Liwa crescent. This was deposited on a pre-MIS 5 land surface, since ca. 6 ka, over a period of just a few thousand years. Contemporary bypassing of eolian sands via superimposed dunes in both Al Qˆafa and Liwa appears to be in equilibrium with the current wind regime. A consideration of a variety of factors that control the availability, mobilization, and preservation of eolian sediments and resulting bedforms leads us to infer that the system is not sediment-supply or transport limited. Instead, the system is preservation limited, being controlled by a correlated combination of sea level and precipitation. Both of these factors are strongly linked to global climate variations in the eccentricity (ca. 100 ka) band. Paradoxically, the bulk of the preserved record of eolian activity in the southern Arabian Peninsula occurs within relatively humid interglacial phases rather than arid intervals. Evidence of eolian deposition during arid phases may not for the most part be preserved in large areas of the sand sea. Observed contrasts in the preserved record of eolian activity between Al Qˆafa and Liwa, and the Wahiba Sand Sea, may in part relate to contrasting eolian bedform morphology. © 2005 Geological Society of America. Regional physiography 1437 Palaeo-environment reconstruction from the geomorphological context of four archaeological sites on the East-Lyonnais plain (Rhˆone, France) (French) (Reconstitution pal´eoenvironnementale a` partir du contexte g´eomorphologique de quatre sites arch´eologiques de la plaine de l’est Lyonnais (Rhˆone, France)) Franc O. Quaternaire 2005 16/2 (95-105) The East-Lyonnais plain, where glaciers have spread debris to form either morainic hills covered with loess or fluvioglacial terraces, has been inhabited by Man from the Mesolithic period to Antiquity. On the hills, where we can see some undulations, an interesting stratigraphy is developed with pedogenesis, colluviums and anthropological impact on the environment. The signatures of these processes are analysed by means of sedimentologic and micromorphologic surveys, methods used as arguments to intepret this kind of stratigraphy. A palaeo-environment reconstruction, supported by radio-carbon and archaelogical dating, is thus proposed for four sites on two of the morainic hills. In conclusion, the thickness of the endorheic depression infill, at different periods, seems to depend on man-made pressure rather than climatic considerations. 1438 Geomorphological and geological studies for Bangladesh: A review (Japanese) Takagi T., Oguchi T., Zaiki M. and Matsumoto J. Chikei/Transactions, Japanese Geomorphological Union 2005 26/4 (405-422) Rapid geomorphological changes mainly due to fluvial processes have been uccurring in Bangladesh despite its very flat topography. This observation reflects its location in the downstream areas of the two large rivers: Ganges and Brahmaputra, with their upstream areas being subjected to abundant rainfall. Fluvial systems in Bangladesh are quite complex, because the meandering Ganges and the braided Brahmaputra merges in the center of the country, and southern plains are prone to tide-related processes. Despite such interesting geomorphological settings, detailed scientific studies on landforms and sediments in Bangladesh have 272 LANDFORMS only been activated since the 1990s, because of political chaos in the earlier decades and a limited number of researchers within the country. It is necessary to extend recent studies to better understand the geomorphology of the country. This paper reviews the history and contents of geomorphological and geological studies for Bangladesh, to facilitate future progress of relevant research. Although this paper intends to cover a wide range of topics, special attention is directed toward fluvial geomorphology in relation to frequent large floods, which significantly affect people’s life in Bangladesh. Neotectonics and structural control 1439 Late Quaternary systematic stream offsets caused by repeated large seismic events along the Kunlun fault, northern Tibet Fu B., Awata Y., Du J. and He W. Geomorphology 2005 71/3-4 (278-292) The Kunlun fault is one of the largest strike-slip faults in northern Tibet, China. In this paper, we focus upon the Kusai LakeKunlun Pass segment of the fault to understand the geomorphic development of offset streams caused by repeated large seismic events, based on tectono-geomorphic analysis of high-resolution satellite remote sensing images combined with field studies. The results indicate that systematic left-lateral stream offsets appear at various scales across the fault zone: Lateral offsets of small gullies caused by the 2001 Mw 7.8 Kunlun earthquake vary typically from 3 m to 6 m, meanwhile streams with cumulative offsets of 10 m, 25-30 m, 50-70 m, 250-300 m and 750-1400 m have resulted from repeated large seismic events during the late Quaternary. An average slip rate of 10 1 mm/year has been estimated from the lateral stream offsets and 14 C ages of alluvial fan surfaces incised by the streams. A three-dimensional model showing tectono-geomorphic features along a left-lateral strikeslip fault is also presented. The Kusai Lake-Kunlun Pass segment provides an opportunity to understand the relationship between geomorphic features produced by individual large seismic events and long-term geomorphic development caused by repeated large seismic events along a major strike-slip fault. © 2005 Elsevier B.V. All rights reserved. 1440 Regional relief characteristics and denudation pattern of the western Southern Alps, New Zealand Korup O., Schmidt J. and McSaveney M.J. Geomorphology 2005 71/3-4 (402-423) The Southern Alps of New Zealand are the topographic expression of active oblique continental convergence of the Australian and Pacific plates. Despite inferred high rates of tectonic and climatic forcing, the pattern of differential uplift and erosion remains uncertain. We use a 25-m DEM to conduct a regional-scale relief analysis of a 250-km long strip of the western Southern Alps (WSA). We present a preliminary map of regional erosion and denudation by overlaying mean basin relief, a modelled stream-power erosion index, river incision rates, historic landslide denudation rates, and landslide density. The interplay between strong tectonic and climatic forcing has led to relief production that locally attains 2 km in major catchments, with mean values of 0.65-0.68 km. Interpolation between elevations of major catchment divides indicates potential removal of l01 103 km3 , or a mean basin relief of 0.51-0.85 km in the larger catchments. Local relief and inferred river incision rates into bedrock are highest about 50-67% of the distance between the Alpine fault and the main divide. The mean regional relief variability is 0.5 km. Local relief, valley cross-sectional area, and catchment width correlate moderately with catchment area, and also reach maximum values between the range front and the divide. Hypsometric integrals show scale dependence, and together with hypsometric curves, are insufficient to clearly differentiate between glacial and fluvial dominated basins. Mean slope angle in the WSA ( = 30°) is lower where major longitudinal valleys and extensive ice cover occur, and may be an insensitive measure of regional relief. Modal slope angle is strikingly uniform throughout the WSA ( = 38-40°), and may record adjustment to runoff and landsliding. Both and show non-linear relationships with elevation, which we attribute to dominant geomorphic process domains, such as fluvial processes in lowaltitude valley trains, surface runoff and frequent landsliding on montane hillslopes, "relief dampening" by glaciers, and rock fall/avalanching on steep main-divide slopes. © 2005 Elsevier B.V. All rights reserved. 1441 Magmatic and tectonic history of Iceland’s western rift zone at Lake Thingvallavatn Bull J.M., Minshull T.A., Mitchell N.C. et al. Bulletin of the Geological Society of America 2005 117/11-12 (1451-1465) High rates of Holocene sedimentation in a lake spanning the Thingvellir rift zone of western Iceland provide an unusual opportunity to study the interaction of tectonic and magmatic processes on time scales of thousands of years. Lake Thingvallavatn is oriented SW-NE, parallel to the trend of normal faults and fissures, which extend northeast from Hengill, a central volcano system. Thingvallavatn’s lake sediments provide a continuous high-fidelity record of tectono-magmatic processes. Chirp subbottom profiler and sidescan records, together with sediment core information, enabled us to improve constraints on lake stratigraphy since the emplacement of a postglacial lava at 9.1 0.3 ka. This lava, together with three younger horizons, enabled detailed study of the main tectonic and magmatic events. A major Hengill volcanic event, which controlled the development of the present-day lake morphology, occurred at 1.9 ka, with the eruption of a scoria cone within the lake (Sandey). During this event, the Nesjahraun lava was erupted into the southern part of the lake, the Sandey scoria cone was formed, and major faulting and subsidence occurred in the northern part of the lake, resulting in the formation of an asymmetrical rift. Within the southern part of the lake, a deformed sequence of sediments aged 2.9-1.5 ka, between undeformed younger and older sediments, indicates that liquefaction phenomena are associated with the emplacement of the Nesjahraun lava. Analysis of fault displacement reveals that the total throw summed over all faults across the width of the rift zone is approximately constant (110-130 m) along the long axis of the rift. We estimate an extension rate on the faults of 3.3-8.2 mm yr-1 since 9.1 ka, assuming fault dips of 60-75°, which represents 17%-43% of the total plate boundary extension estimated from global plate motion inversion. We speculate that the remaining extension must either be taken up elsewhere in Iceland, for example in the eastern rift zone or along the South Iceland seismic zone, or that extension estimated over the last 9 k.y. underestimates the long-term extension rate due to incomplete sampling of the episodic magmatic component. © 2005 Geological Society of America. 1442 Recognition of past earthquakes along the Sparta fault (Peloponnesus, southern Greece) during the Holocene, by combining results of different dating techniques Papanastassiou D., Gaki- Papanastassiou K. and Maroukian H. Journal of Geodynamics 2005 40/2-3 (189-199) Sparta fault is an impressive landform, located on the eastern front of Taygetos mountain, southern Greece. Detailed morphotectonic observations on this fault suggest that it should be active at least since Early Quaternary. However, according to the current seismological knowledge, this region is characterized by very low seismicity. The only reported earthquake to have occurred in this area is that of 464 b. c., a destructive event that devastated the whole city of Sparta. In order to get information on the occurrence of past earthquakes during the Holocene, results of different independent dating works that have performed along the Sparta fault were used. These researchers confirm the existence not only of the 464 B.C. earthquake but also of several more that occurred at ca. 3900 b. c., 2500 B.C. and 2000 B.C., 550 A.D. and 1000 A.D. The events that occurred at 2500 and 464 B.C. should correspond to major events of magnitude of the order of 7, which ruptured the entire length of the fault, while these at 3900 B.C., 2000 B.C., 550 A.D. and 1000 A.D., to smaller events of magnitude 6-6.5. The return periods of strong earthquakes along the Sparta fault is estimated to be around 2000 years, but within these periods events of smaller magnitude that ruptured segments of the fault have also occurred. © 2005 Elsevier Ltd. All rights reserved. LANDFORMS 1443 Neotectonic map of Syria and some aspects of Late Cenozoic evolution of the northwestern boundary zone of the Arabian plate Rukieh M., Trifonov V.G., Dodonov A.E. et al. Journal of Geodynamics 2005 40/2-3 (235-256) The neotectonic map of Syria, 1:500,000, was compiled by the authors in 2003-2004. The map shows tectonic features formed or continued to develop during the Neogene and Quaternary in Syria and adjacent territories, including the Mediterranean realm. The neotectonic structure of the region was formed as a result of three phases of deformation. During the Early Miocene first phase, the Arabian plate moved along the Dead Sea-Jordan segments of the Levant (Dead Sea) transform fault zone, Roum fault and its continuation in the continental slope of the Mediterranean. The chain of the coastal anticlines in the "Arabian" side of the transform zone and the Lattaqie oblique (sinistral-thrust) boundary fault zone in the north were formed under the NNW-trending compression. The Lattaqie zone continued by the Cyprus arc in the west and by the Taurus (Bitlis) thrust in the east and further by the Main Thrust of the Zagros. After "quiet" (for Syria) epoch of the Middle Miocene when the Arabian plate moved to the NE, during the Late Miocene second phase of deformation, the Arabian plate moved again to the NNW along the same transform boundary. But a part of the Late Miocene plate motion (up to 20 km) resulted by shortening in the Anti-Leban-Palmyride foldthrust belt that separated the Aleppo block from the main part of the Arabian plate. During the Pliocene-Quaternary third phase of deformation, the recent structural pattern of the Levant zone was formed in Lebanon and the northwestern Syria. At the same time, the Serghaya and smaller sinistral faults branched out the Levant zone and the system of the W-E-trending convex to the south dextral faults ruptured the Palmyrides and the stable part of the Arabian plate. The total Pliocene-Quaternary sinistral offset on the young Levant zone segments and the associated faults has reached 35-40 km, like on the Dead Sea-Jordan segments of the Levant fault zone. The faults, demonstrating the PlioceneQuaternary activity are still active now and represent the main seismic zones in Syria. Offsets on them are mostly a cumulative effect of strong earthquakes. © 2005 Published by Elsevier Ltd. 1444 Paleoseismology in Venezuela: Objectives, methods, applications, limitations and perspectives Audemard M. F.A. Tectonophysics 2005 408/1-4 (29-61) The privileged location of Venezuela along an active interplate deformation belt, despite of being a "so-called" developing country, has led to a long paleoseismic tradition as attested by 45 trench assessments since 1968. Since then, a first 2-trench study was carried out by the American Woodward-Clyde company across the Oca fault at Sinamaica. Since 1980, all further paleoseismic studies have been performed by FUNVISIS and the Uribante-Caparo hydroelectric project (southern M´erida Andes) became their first assessment where 22 huge trenches were bulldozer-dug. Except for these Compa˜na An´onima de Administraci´on y Fomento El´ectrico (CADAFE) financed trenches and two others, all other assessments were for Petr´oleos de Venezuela S. A. -PDVSA-. In this paper, geographic and geologic factors, as well as logistic limitations, conditioning success in paleoseismic studies by trenching, shall be discussed based on the Venezuelan experience developed over the years. The scientific contribution of this approach refer to: confirmation of Holocene fault activity, slip-per-event and average slip rate of a given fault (or segment), seismic potential (repeat of maximum credible earthquakes) of known faults, fault segmentation, fault interaction as consequence of stress loading by stick-slip on contiguous faults, time-space distribution of seismic activity along a given tectonic feature, seismotectonic association of historical earthquakes and landscape evolution on the short term and its implications on the long-term evolution (poorly discussed since this is really part of the field of Neotectonics). In recent years (since 1999), a new approach has been introduced in Venezuela consisting in complementing the seismic history derived from trenching studies with the evaluation of seismically induced perturbations in the continuous Quaternary sedimentary record of (either active or fossil) lakes. The future of this discipline in Venezuela heads to more trenching and lake coring in order to gather more data on the previously mentioned aspects. Other paleoseismic approaches have been developed very little in Venezuela since either climate 273 or the geodynamic setting do not favor their application. © 2005 Elsevier B.V. All rights reserved. 1445 Some considerations concerning seismic geomorphology and paleoseismology Dramis F. and Blumetti A.M. Tectonophysics 2005 408/1-4 (177191) Seismic geomorphology studies landforms which developed in connection with earthquakes. Among them, two different end members may be distinguished: 1) seismo-tectonic landforms, including surface faults and fractures, land uplift and subsidence at different scales, surface bulges, elongate ridges, and any other permanent ground deformations directly related to tectonic stress, and 2) seismo-gravitational landforms, such as landslides, deepseated gravitational slope deformations, sinkholes, and fissures due to sediment compaction or liquefaction and sand blows, connected with both seismic shaking and gravitational stress. A clear-cut distinction between the two categories of landforms is not always easy to make (and in many instances not really useful), while there are, in many cases, ground effects that might be (and should be) considered as simultaneous combinations of seismo-tectonic and seismo-gravitational processes. This applies especially to surface fracturing and faulting which could be the combined result of tectonic stress, stress produced by seismic shaking, and gravitational stress. The objective of this paper is to review selected case histories mainly from Italy and the Mediterranean region, in order to show the importance of a comprehensive study of earthquake-generated landforms for understanding the seismicity level of the area under investigation. We argue that in earthquake prone areas, seismic landforms often constitute typical patterns (seismic landscapes) whose recognition, mapping and paleoseismological analysis may help in the evaluation of seismic hazards. © 2005 Elsevier B.V. All rights reserved. Landforms of other planets 1446 Stratigraphy and sedimentology of a dry to wet eolian depositional system, Burns formation, Meridiani Planum, Mars Grotzinger J.P., Arvidson R.E., Bell III J.F. et al. Earth and Planetary Science Letters 2005 240/1 (11-72) Outcrop exposures of sedimentary rocks at the Opportunity landing site (Meridiani Planum) form a set of genetically related strata defined here informally as the Burns formation. This formation can be subdivided into lower, middle, and upper units which, respectively, represent eolian dune, eolian sand sheet, and mixed eolian sand sheet and interdune facies associations. Collectively, these three units are at least 7 m thick and define a "wetting-upward" succession which records a progressive increase in the influence of groundwater and, ultimately, surface water in controlling primary depositional processes. The Burns lower unit is interpreted as a dry dune field (though grain composition indicates an evaporitic source), whose preserved record of large-scale cross-bedded sandstones indicates either superimposed bedforms of variable size or reactivation of leeside slip faces by episodic (possibly seasonal) changes in wind direction. The boundary between the lower and middle units is a significant eolian deflation surface. This surface is interpreted to record eolian erosion down to the capillary fringe of the water table, where increased resistance to wind-induced erosion was promoted by increased sediment cohesiveness in the capillary fringe. The overlying Burns middle unit is characterized by finescale planar-laminated to low-angle-stratified sandstones. These sandstones accumulated during lateral migration of eolian impact ripples over the flat to gently undulating sand sheet surface. In terrestrial settings, sand sheets may form an intermediate environment between dune fields and interdune or playa surfaces. The contact between the middle and upper units of the Burns formation is interpreted as a diagenetic front, where recrystallization in the phreatic or capillary zones may have occurred. The upper unit of the Burns formation contains a mixture of sand sheet facies and interdune facies. Interdune facies include wavy bedding, irregular lamination with convolute bedding and 274 LANDFORMS possible small tepee or salt-ridge structures, and cm-scale festoon cross-lamination indicative of shallow subaqueous flows marked by current velocities of a few tens of cm/s. Most likely, these currents were gravity-driven, possibly unchannelized flows resulting from the flooding of interdune/ playa surfaces. However, evidence for lacustrine sedimentation, including mudstones or in situ bottom-growth evaporites, has not been observed so far at Eagle and Endurance craters. Mineralogical and elemental data indicate that the eolian sandstones of the lower and middle units, as well as the subaqueous and eolian deposits of the Burns upper unit, were derived from an evaporitic source. This indirectly points to a temporally equivalent playa where lacustrine evaporites or ground-water-generated efflorescent crusts were deflated to provide a source of sand-sized particles that were entrained to form eolian dunes and sand sheets. This process is responsible for the development of sulfate eolianites at White Sands, New Mexico, and could have provided a prolific flux of sulfate sediment at Meridiani. Though evidence for surface water in the Burns formation is mostly limited to the upper unit, the associated sulfate eolianites provide strong evidence for the critical role of groundwater in controlling sediment production and stratigraphic architecture throughout the formation. © 2005 Elsevier B.V. All rights reserved. Slopes 1447 Slope movements as a disturbance agent increasing heterogeneity and biodiversity of landscape in Eastern Moravia Kirchner K. and Lacina J. Ekologia Bratislava 2004 23/SUPPL. 1 (94-103) The paper is devoted to the characterisation of complex relations between vegetation cover and slope movements, especially sliding, in the Vsetn region in the eastern Moravia. The area is a part of highland flysch relief of the Outer Western Carpathians, where the extreme rainfall of July 1997 activated a lot of slope deformations. It was recognised on the basis of biogeographic (geobiocoenologic) and geomorphic investigations of 20 study sites that landslides originate in various potential as well as actual vegetation types. The process of sliding alters the ecological conditions of the site which results to the change of the geobiocoen type; slope movements as a disturbance agent increase the landscape heterogeneity and biodiversity. 1448 An attempt to refine rockfall hazard zoning based on the kinetic energy, frequency and fragmentation degree Jaboyedoff M., Dudt J.P. and Labiouse V. Natural Hazards and Earth System Science 2005 5/5 (621-632) Rockfall hazard zoning is usually achieved using a qualitative estimate of hazard, and not an absolute scale. In Switzerland, danger maps, which correspond to a hazard zoning depending on the intensity of the considered phenomenon (e.g. kinetic energy for rockfalls), are replacing hazard maps. Basically, the danger grows with the mean frequency and with the intensity of the rockfall. This principle based on intensity thresholds may also be applied to other intensity threshold values than those used in Switzerland for rockfall hazard zoning method, i.e. danger mapping. In this paper, we explore the effect of slope geometry and roc kfall frequency on the rockfall hazard zoning. First, the transition from 2D zoning to 3D zoning based on rockfall trajectory simulation is examined; then, its dependency on slope geometry is emphasized. The spatial extent of hazard zones is examined, showing that limits may vary widely depending on the rockfall frequency. This approach is especially dedicated to highly populated regions, because the hazard zoning has to be very fine in order to delineate the greatest possible territory containing acceptable risks. © 2005 Author(s). This work is licensed under a Creative Commons License. 1449 The Influence of the North Atlantic Oscillation on rainfall triggering of landslides near Lisbon Trigo R.M., Zˆezere J.L., Rodrigues M.L. and Trigo I.F. Natural Hazards 2005 36/3 (331-354) The majority of landsliding episodes in the area north of Lisbon are associated with rainfall events of short (less than 5 days) medium (5-20 days) or long duration (more than 20 days). The precipitation regime in Portugal is highly irregular, with large differences between wet and dry years. We have assessed the impact of the North Atlantic Oscillation (NAO) on both the winter precipitation and the timing and magnitude of associated landslide events. Results show that the large inter-annual variability of winter precipitation is largely modulated by the NAO mode. The precipitation composite corresponding to high NAO index presents a considerable lower median value (47 mm/month) than the corresponding low NAO index class (134 mm/month). The entire precipitation distribution associated with the low NAO index composite encompasses a wider range of values than the corresponding high NAO index composite. This non-linear behavior is reflected in the probability of occurrence of a very wet month (precipitation above the 90% percentile) that is just 1% for the positive NAO class and 23% for low NAO index months. Results for the low NAO class are crucial because these months are more likely associated with long-lasting rainfall episodes responsible for large landslide events. This is confirmed by the application of a 3-month moving average to both NAO index and precipitation time series. This procedure allowed the identification of many months with landslide activity as being characterized by negative average values of the NAO index and high values of average precipitation (above 100 mm/month). Finally, using daily data we have computed the return periods associated with the entire set of landslide episodes and, based on these results, obtained a strong linear relationship between critical cumulative rainfall and the corresponding critical rainfall event duration. © Springer 2005. 1450 Case history of landslide movement during the Northridge earthquake Pradel D., Smith P.M., Stewart J.P. and Raad G. Journal of Geotechnical and Geoenvironmental Engineering 2005 131/11 (1360-1369) We document a case history of Northridge earthquake induced movement of a coherent landslide mass comprised principally of weathered, previously sheared siltstone. Information on the residual shear strength of the material through which the sliding occurred is available both from backanalysis of a static (rainfall-induced) failure on the same slope and laboratory test data. Postearthquake field reconnaissance data establishes the seismic slope displacements near the slope crest. A yield coefficient is estimated for the slope based on residual shear strengths and measured groundwater levels at the time of the Northridge earthquake. This yield coefficient is used with four horizontal equivalent acceleration time histories (that approximate the seismic demand within the slide mass) in Newmark sliding block displacement analyses. The calculated displacements range from approximately 20 to 90 mm, which compares well with observed displacements at the slide scarp of approximately 50 mm. Journal of Geotechnical and Geoenvironmental Engineering © ASCE. 1451 Reliability analysis of unsaturated soil slopes Sivakumar Babu G.L. and Murthy D.S.N. Journal of Geotechnical and Geoenvironmental Engineering 2005 131/11 (14231428) Many soil slopes are unsaturated in their initial state, and suction contributes to initial stability. Stability of these slopes decreases as suction decreases with time due to rainfall infiltration and water redistribution. Many of the parameters in the assessment of stability are highly variable. In this technical note, sensitivity/reliability analysis of design variables for a typical unsaturated soil slope is conducted. Sensitivity analysis shows that suction parameters have significant influence on the stability. Reliability computations performed for the slope considered show that failure zones are better captured by the reliability index than the conventional factor of safety. The study also shows that variation of saturated hydraulic conductivity significantly influences slope reliability. Journal of Geotechnical and Geoenvironmental Engineering © ASCE. 1452 On the use of Saint Venant equations to simulate the spreading of a granular mass Mangeney- Castelnau A., Bouchut F., Vilotte J.P. et al. Journal of Geophysical Research B: Solid Earth 2005 110/9 (1-17) LANDFORMS Cliff collapse is an active geomorphological process acting at the surface of the Earth and telluric planets. Recent laboratory studies have investigated the collapse of an initially cylindrical granular mass along a rough horizontal plane for different initial aspect ratios a = Hi /Ri , where Hi and Ri are the initial height and radius, respectively. A numerical simulation of these experiments is performed using a minimal depth-integrated model based on a long-wave approximation. A dimensional analysis of the equations shows that such a model exhibits the scaling laws observed experimentally. Generic solutions are independent of gravity and depend only on the initial aspect ratio a and an effective friction angle. In terms of dynamics, the numerical simulations are consistent with the experiments for a 1. The experimentally observed saturation of the final height of the deposit, when normalized with respect to the initial radius of the cylinder, is accurately reproduced numerically. Analysis of the results sheds light on the correlation between the area overrun by the granular mass and its initial potential energy. The extent of the deposit, the final height, and the arrest time of the front can be directly estimated from the "generic solution" of the model for terrestrial and extraterrestrial avalanches. The effective friction, a parameter classically used to describe the mobility of gravitational flows, is shown to depend on the initial aspect ratio a. This dependence should be taken into account when interpreting the high mobility of large volume events. Copyright 2005 by the American Geophysical Union. 1453 Classifying and assessing the geologic contribution to rockfall hazard Vandewater C.J., Dunne W.M., Mauldon M. et al. Environmental and Engineering Geoscience 2005 11/2 (141-154) Rockfalls from roadcuts are a major hazard and pose problems for transportation agencies across the country. In the context of rockfall hazard management, however, no consensus exists about the role of geology in assessing rockfall hazard. This study investigates the geologic contribution to rockfall hazard through application of rockfall hazard rating systems to roadcuts in Tennessee and through additional data collection to reveal correlations between hazard characteristics and geologic attributes. The geologic character of 80 roadcuts in central and eastern Tennessee was evaluated using the Tennessee Rockfall Hazard Rating System (RHRS), which is a revision of the National Highway Institute (NHI) RHRS. Scores for both RHRSs were compared to evaluate whether the improved reproducibility of scoring for the Tennessee RHRS yielded unintended losses of scoring accuracy and sensitivity. Additional geologic attribute data beyond those used in the RHRS system were collected to determine with logistic regression analysis whether relationships among the geologic attributes, rockfall type, and block size exist. Results indicate the revised geologic component of Tennessee’s RHRS is more informative and permits description of a wider spectrum of geologic conditions than does the NHI version. Logistic regression analysis indicates rockfall type correlates to lithologic variation and the number of discontinuity sets; and block size correlates to structurally controlled rockfall, lithologic variation, mechanical layer thickness, and number of discontinuity sets. Consequently, roadcuts containing potential rockfall modes with two or more discontinuity sets, no lithologic variation, and mechanical thicknesses that exceed 1.0 m are expected to have greater Geologic Character scores. 1454 Risk-based definition of zones for land-use planning in snow avalanche terrain McClung D.M. Canadian Geotechnical Journal 2005 42/4 (1030-1038) For avalanche applications, the definition of zones for land-use planning typically involves estimates of both return period and impact pressures as functions of position in the runout zone. Since return period is related to expected avalanche frequency and impact pressure is related to consequences if structures are bit, zone specifications imply a risk-based approach. In this paper, the schemes for definition of zones from three countries (Switzerland, Canada, and Austria) are presented and compared from a mathematical, risk-based framework. The comparison reveals that the Swiss standard is the least conservative and the Austrian standard is the most conservative. © 2005 NRC Canada. 275 1455 Geological and morphological study of the Jiufengershan landslide triggered by the Chi-Chi Taiwan earthquake Chang K.- J., Taboada A. and Chan Y.- C. Geomorphology 2005 71/3-4 (293-309) The Jiufengershan rock and soil avalanche is one of the largest landslides triggered by the Chi-Chi earthquake Taiwan 1999. The landslide destabilized the western limb of the Taanshan syncline along a weak stratigraphic layer. It involved a flatiron remnant, which was almost entirely mobilized during the earthquake. The avalanche was slowed down by NS trending ridges located downstream along the Jiutsaihu creek. The landslide affected a 60 m thick and 1.5 km long sedimentary pile composed of shales and sandstones, which dip 22°SE toward a transverse valley. The triggering mechanism and the sliding process were analyzed by means of geological and morphological data from aerial photographs and observed in the field. A high-resolution airborne Light Detection and Ranging (LiDAR) image taken 2.5 years after the landslide allows the identification of morphological structures along the sliding surface and the landslide accumulation. The sliding surface shows several deformation structures such as fault scarps and folds. These structures are interpreted in terms of basal shear stresses created during the avalanche. Three major joint sets were identified at the sliding surface. The isopach map of the landslide was calculated from the comparison between elevation models before and after the earthquake. The coseismic volume of mobilized material and landslide deposit data are 42 106 m3 and 50 106 m3 , respectively. The geometry of the landslide accumulation in the field has an irregular star shape. The morphology of the deposit area shows a sequence of smooth reliefs and depressions that contrast with the neighboring ridges. © 2005 Elsevier B.V. All rights reserved. 1456 The 1786 earthquake-triggered landslide dam and subsequent dam-break flood on the Dadu river, southwestern China Chanson H. Geomorphology 2005 71/3-4 (437-440) Forensic studies of past hydraulic structure failures are rare despite their critical relevance to modern hydraulic design, and the writers (Dai et al., 2005) must be congratulated for their outstanding study. Herein the discussion is focused on two aspects of the conclusion. It is believed that dam overtopping was the primary cause of the Dadu river landslide dam failure, although aftershocks may have further weakened the embankment. Using physically based equations supported by recent physical model data, the maximum outflow may be estimated to be about 6000 m3 /s. © 2005 Elsevier B.V. All rights reserved. 1457 The statistical relationship between unconfined compressive strengths and the frequency distributions of slope gradients - A case study in northern Hungary P¨usp¨oki Z., Szab´o S., Demeter G. et al. Geomorphology 2005 71/3-4 (424-436) This paper focuses on the question of whether there is a deterministic connection between the slope gradient and unconfined compression strength (UCS) as a lithological factor and on describing the nature of this connection. Moreover, the authors determined the sensitive statistical parameters in the statistical surface analyses. The surface analyses were carried out in an area extending over 1500 km2 in northern Hungary and containing parts of the uplifted Palaeozoic and Mesozoic basement and the semi-consolidated material of the Palaeogene and Neogene molasse sediments. The 67 geological formations of the area were grouped into 10 petrophysical categories characterised by unconfined compressive strength as a petrophysical parameter. The geological database was the digitalized geological map of North Hungarian Region (1 : 100 000). The digital topographic database was based on 10 m contour lines of 1 : 50 000 maps, the digital elevation model was generated by kriging interpolation. Three topographic models were created with resolutions of 25 25, 50 50 and 100 100 m per pixels. Evident correlation can be shown between the UCS and the relative frequency of the slope gradient. The adequate regression procedure is the power regression for low slope category values while logarithmic regression is applicable at high slope angles. Based on the characteristic of the relationship and the value of r2 , slope category intervals can be identified the relative frequency of which is proven to be determined by the UCS. These intervals are found to be between 276 LANDFORMS 4-10%, 10-16%, 16-22%, 22-44% and over 44%. Using the determination equations of slope gradient between 4-10% and over 44%, the UCS of the bedrock can be calculated approximately as the average value of the two calculated results. So the quotient of the frequency of these two category intervals can be regarded as an important morphometric index for a given bedrock. From the aspect of petrophysical characteristics, the rock with UCS between 6 and 86 MPa were proven to be deterministic for the slope development i.e. in the determination of the slope category frequencies. Applying the relative frequency of slope gradients a relative erosion resistance of the petrophysical categories can be calculated. Considering the determination coefficients, among the statistical parameters of the distribution of slope category values the standard deviation, mode, mean and median proved to be determined by the UCS of the bedrock. © 2005 Elsevier B.V. All rights reserved. 1458 Analysis of dynamic factors of debris landslide by means of the model of quantitative theory - Using the Xintan landslide, China, as an example Keqiang H., Jibao Y. and Sijing W. Environmental Geology 2005 48/6 (676-681) If prediction of a debris landslide is to be completed, the first problem is how to determine and correlate the dynamic factors. The special composition and complicated geological conditions of debris landslides have many dynamic factors influencing displacement and stability. Correlations are generally very complicated. The relationship and sequence of factors is too complex to be completed by traditional mathematical model. In order to solve the problem above, a systematical study of the quantitative and qualitative dynamic factors using a model of the quantitative theory was performed based on the displacements of Xintan landslide, China. Rainfall was found to be the most important dynamic factor among the six factors controlling displacements. Relative importance sequence and correlation was also established. All prediction results agree with the mechanism and displacement pattern of the Xintan landslide. Optimized measures of prevention and control for debris landslides can be completed with correlation of the dynamic factors by means of the quantitative theory model. © Springer-Verlag 2005. 1459 Distribution of landslides adjacent to the northern side of the Yarlu Tsangpo Grand Canyon in Tibet, China Shang Y., Park H.- D., Yang Z. and Yang J. Environmental Geology 2005 48/6 (721-741) This paper presents results of recent studies on distribution and category of landslides in one section of the Sichuan-Tibet Highway, adjacent to the northern side of the Yarlu Tsangpo Grand Canyon, Tibet, Southwestern China. In the tectonic setting predominated by compression and strike-slipping, active faults are dominant and result in the genesis of the great alpine relief together with fluvial incision and unloading. In this section, with a distance of about 290 km between Ranwu and Lulang, 34 landslides occurred. Among them, the 12 large and super-large landslides comprise the most dangerous part of the highway system to road users over the past 50 years. The landslides usually occurred in slopes comprised of moraine with a large thickness, fluvio-pluvial and lacustrine deposits and fractured rocks. Based on the examination of the physical geography, structural geology, Quaternary geology, stratigraphy and petrography, this paper presents the temporal-spatial distribution of landslides along the section and classification of them into three types with respect to mechanism and composites of landslides. Type 1. Landslide initiated at high elevation and transformed into a distal debris flow damming the river with a long reoccurrence interval Type 2. Landslide at stream banks, in different ranks of mass movements in dissecting layers of moraines Type 3. Landslide of fractured rock mass with quick translation movements. Each of the three types is presented by distinctive case examples. Type 1 is Yigong Landslide; type 2 includes Dongjiu Landslide group, 102 Landslide group, Suotong Landslide group, Songzong Landslide; and the type 3 is Layue Landslide. A binary landslide, which is seldom seen in nature and which occurred in the outlet of one creek under the integrative function of fluvial incision and road cut, is also presented. These are distributed in different parts of the area with characterized structural geology, topography and composites (gneiss and Quaternary deposits) with accumulative quantity between Suotong and Dongjiu. The most occurred with frequent and rapid translation, shallow shearing planes, various influential factors and unique triggering factors, and a variable period of reoccurrence with a tendency of increasing magnitude. In this region, six influential factors greatly contribute to their occurrence: (a) intensive neotectonic movements, (b) ongoing alpine canyon relief, (c) earthquakes, (d) heavy precipitation, (e) stream erosion, and (f) human activities, to a certain extent. Mostly, the latter four factors play major roles in triggering landslide occurrence. The earthquake causes the rock and soil to fracture and deform, and tends to be unstable, or cause earth-induced landslides. The heavy rainfall in monsoon seasons which saturates the soil and lower the shearing strength is mostly responsible for the occurrence of landslides. The stream erosion disturbs slope toes causing progressive failure. Road construction and deforestation decrease the natural slope stability. Comments and suggestions on the physical measures for remediation of landslides and safety of highways are also made. © Springer-Verlag 2005. 1460 Location of critical three-dimensional non-spherical failure surface by NURBS functions and ellipsoid with applications to highway slopes Cheng Y.M., Liu H.T., Wei W.B. and Au S.K. Computers and Geotechnics 2005 32/6 (387-399) At present, location of critical three-dimensional failure surfaces is mainly limited to spherical shape due to the various difficulties in performing global optimization for general non-spherical failure surface. Non-spherical failure surface is however the most general and critical shape that should be considered in slope stability analysis. This paper introduces a practical way in using NURBS surface and ellipsoidal surface to simulate a three-dimensional sliding surface. Numerical examples have indicated that the present proposal is effective in application and the critical failure surfaces as determined for 2 specially designed problems are also reasonable. The authors have also applied the optimization search to a curved highway slope and have obtained the relation between curvature of slope and the minimum factors of safety of slope. © 2005 Elsevier Ltd. All rights reserved. Soil mechanics 1461 Engineering-related slope failure in permafrost regions of the Qinghai-Tibet Plateau Niu F., Cheng G., Ni W. and Jin D. Cold Regions Science and Technology 2005 42/3 (215-225) Thaw slumping existing on two slopes in permafrost region of the Qinghai-Tibet Plateau is studied with their geological features, deformations and ground temperature in this paper. The failure shows as collapse and slide of active layer along the massive ground-ice surface. The field-monitored data show that the retrogressively extending area, soil-body sliding velocity and the water content of the soils in the failed area strikingly change with the air temperature and slope facing aspect. On the southfacing slope, the values of all of these items are higher than that on the north-facing slope. The mean annual ground temperature in the failed area on the south-facing slope is evidently higher than that in the undisturbed natural ground and that in the northfacing slope. In addition, the input of heat into the permafrost below the sliding mass on the south-facing slope is more than the output. Therefore the permafrost in the slope processes degradation when landslide occurs. The genesis of this kind of slope failure is closely related to ice-rich frozen soils and activities of engineering cut. Based on static balance analysis, the stability estimating method for such landslide is presented considering the seepage of ice-melting ground water in the paper. At last, the engineering measures of preventing thaw slumping are proposed too. © 2005 Elsevier B.V. All rights reserved. 1462 Numerical analysis of a landslide in soils with strainsoftening behaviour Troncone A. Geotechnique 2005 55/8 (585-596) The results of an analysis concerning a landslide of great dimensions, which occurred at Senise (Southern Italy) on 26 July 1986, are presented. The landslide was of a translational type, and the LANDFORMS failure developed within a thin clayey silt layer interbedded by a slightly cemented sand formation. Both these soils experienced a pronounced strain-softening behaviour during laboratory tests. From the analyses performed using the traditional limit equilibrium approach, it has been found that the average operational resistance along the sliding surface was less than that of the peak and greater than the residual resistance deduced from the laboratory tests. As a consequence, it has been postulated that a progressive failure had occurred. Such a failure process can be appropriately studied using methods that are capable of simulating the formation and development of shear zones, where strain is localised. From a computational point of view this presents many difficulties, because the numerical procedures currently used are very often affected by a lack of convergence, and the solution may depend strongly on the mesh adopted. In order to overcome these numerical drawbacks, in the present study use is made of both an elasto-viscoplastic constitutive model and a non-local elasto-viscoplastic model implemented in a finite element code. The Mohr-Coulomb plastic law is adopted, and the strain-softening behaviour of the soil is simulated by reducing the strength parameters with the accumulated deviatoric plastic strains. The results of the analysis show that a progressive failure occurred owing to deep excavations carried out at the toe of the slope. In addition, the soil mass involved in the sliding and the location of the failure surface deduced from the numerical simulation are found to be very similar to those observe. Karst 1463 Modeling the influence of epikarst evolution on karst aquifer genesis: A time-variant recharge boundary condition for joint karst-epikarst development Bauer S., Liedl R. and Sauter M. Water Resources Research 2005 41/9 (1-12) [1] The epikarst, a zone of increased weathering near the land surface, determines the distribution of recharge to a karst aquifer in both space and time. It links climatic and near-surface geological conditions with the karstification of a limestone aquifer, defining both the hydraulic and the chemical boundary conditions for the development of the karst system. Realistic modeling of the epikarst is therefore a prerequisite for the simulation of karst aquifer genesis. A conceptual model of the joint karstepikarst evolution is presented in this paper. An epikarst module is developed and implemented in a numerical continuum-discrete conduit flow model for karst genesis, which accounts for the joint evolution of the epikarst and the main karstic conduit network under unconfined conditions. The influence of epikarst genesis on the evolution of the underlying karst aquifer is investigated in four scenarios. It is found that only the interaction of epikarst and initial heterogeneity in the underlying carbonate rock leads to the development of a dendritic cave system. If no heterogeneity in the initial conduit network or in the recharge distribution is included, maze-type caves develop. Copyright 2005 by the American Geophysical Union. 1464 Solution-collapse breccias of the Minkinfjellet and Wordiekammen Formations, Central Spitsbergen, Svalbard: A large gypsum palaeokarst system Eliassen A. and Talbot M.R. Sedimentology 2005 52/4 (775-794) Large volumes of carbonate breccia occur in the late syn-rift and early post-rift deposits of the Billefjorden Trough, Central Spitsbergen. Breccias are developed throughout the Moscovian Minkinfjellet Formation and in basal parts of the Kazimovian Wordiekammen Formation. Breccias can be divided into two categories: (i) thick, cross-cutting breccia-bodies up to 200 m thick that are associated with breccia pipes and large V-structures, and (ii) horizontal stratabound breccia beds interbedded with undeformed carbonate and siliciclastic rocks. The thick breccias occur in the central part of the basin, whereas the stratabound breccia beds have a much wider areal extent towards the basin margins. The breccias were formed by gravitational collapse into cavities formed by dissolution of gypsum and anhydrite beds in the Minkinfjellet Formation. Several dissolution fronts have been discovered, demonstrating the genetic relationship between dissolution of gypsum and brecciation. Textures and structures 277 typical of collapse breccias such as inverse grading, a sharp flat base, breccia pipes (collapse dolines) and V-structures (cave roof collapse) are also observed. The breccias are cemented by calcite cements of pre-compaction, shallow burial origin. Primary fluid inclusions in the calcite are dominantly single phase containing fresh water (final melting points are ca 0°C), suggesting that breccia diagenesis occurred in meteoric waters. Cathodoluminescence (CL) zoning of the cements shows a consistent pattern of three cement stages, but the abundance of each stage varies stratigraphically and laterally. 18 O values of breccia cements are more negative relative to marine limestones and meteoric cements developed in unbrecciated Minkinfjellet limestones. There is a clear relationship between 18 O values and the abundance of the different cement generations detected by CL. Paragenetically, later cements have lower 18 O values recording increased temperatures during their precipitation. Carbon isotope values of the cements are primarily rock-buffered although a weak trend towards more negative values with increasing burial depth is observed. The timing of gypsum dissolution and brecciation was most likely related to major intervals of exposure of the carbonate platform during Gzhelian and/or Asselian/Sakmarian times. These intervals of exposure occurred shortly after deposition of the brecciated units and before deep burial of the sediments. © 2005 International Association of Sedimentologists. 1465 Gypsum karst and its evolution east of Hafik (Sivas, Turkey) ¨ Doˇgan U. and Ozel S. Geomorphology 2005 71/3-4 (373-388) Sivas and its surroundings is the most important gypsum karst terrain in Turkey with a massive Lower Miocene gypsum formation 750 m thick. The region east of Hafik has a wide variety of well developed karstic features such as karrens, dissolution dolines, collapse dolines, blind valleys, karstic springs, swallow holes, caves, unroofed caves, natural bridges, gorges and poljes. The karstification started in the Early Pliocene. The piezometric level to the east of Hafik has lowered at least 200 m since the Early Pliocene and 90-100 m since the Early Pleistocene. There is a youthful karst (doline karst) on the Higher Plateau (1520-1600 m) and a mature karst on Lower Plateau (1315-1420 m). The mature karst evolved in two stages, first stage where excessively karstic paleovalleys, uvalas and collapse dolines appear and the second stage where poljes, collapse dolines and degraded collapse dolines dominated. © 2005 Elsevier B.V. All rights reserved. 1466 Land subsidence and caprock dolines caused by subsurface gypsum dissolution and the effect of subsidence on the fluvial system in the Upper Tigris Basin (between BismilBatman, Turkey) Doˇgan U. Geomorphology 2005 71/3-4 (389-401) Karstification-based land subsidence was found in the Upper Tigris Basin with dimensions not seen anywhere else in Turkey. The area of land subsidence, where there are secondary and tertiary subsidence developments, reaches 140 km2 . Subsidence depth ranges between 40 and 70 m. The subsidence was formed as a result of subsurface gypsum dissolution in Lower Miocene formation. Although there are limestones together with gypsum and Eocene limestone below them in the area, a subsidence with such a large area is indicative of karstification in the gypsum. The stratigraphical cross-sections taken from the wells and the water analyses also verify this fact. The Lower Miocene gypsum, which shows confined aquifer features, was completely dissolved by the aggressive waters injected from the top and discharged through by Zellek Fault. This resulted in the development of subsidence and formation of caprock dolines on loosely textured Upper Miocene-Pliocene cover formations. The Tigris River runs through the subsidence area between Batman and Bismil. There are four terrace levels as T1 (40 m), T2 (30 m), T3 (10 m) and T4 (4-5 m) in the Tigris River valley. It was also found that there were some movements of the levels of the terraces in the valley by subsidence. The subsidence developed gradually throughout the Quaternary; however no terrace was formed purely because of subsidence. © 2005 Elsevier B.V. All rights reserved. 278 THE QUATERNARY 1467 Analysis of karst hydrodynamics through comparison of dissolved and suspended solids’ transport (French) (Fonctionnnement hydrodynamique des syst`emes karstique par comparaison du transport du mat´eriel dissous et particulaire) Valdes D., Dupont J.- P., Massei N. et al. Comptes Rendus Geoscience 2005 337/15 (1365-1374) In karst systems, rain events often result in a decrease of the conductivity (a tracer of dissolved phase transport) and an increase in turbidity (a tracer of suspended solids transport) at wells and springs. This study shows that the comparison of suspended solids and solute transport by the coupled approach of T - C curves (Turbidity-Conductivity) and autocorrelations gives evidence of the transport processes in the karst network and allows understanding the karst hydrodynamics. © 2005 Acad´emie des sciences. Published by Elsevier SAS. All rights reserved. Anthropogenic landforms 1468 Methods for the characterization of areas sensitive to desertification: An application to the Calabrian territory (Italy) Coscarelli R., Minervino I. and Sorriso- Valvo M. IAHS-AISH Publication 2005 -/299 (23-30) Desertification, as it has been defined by the United Nations Convention to Combat Desertification (UNCCD), represents the whole phenomena of land degradation, resulting from many causes. Southern European countries are considered as areas of new expansion of desertification, caused by inadequate agricultural practices, overgrazing, and deforestation, which increase anthrophic pressure. During the last few years, in the context of several international research projects, methodologies were proposed, based on various parameters. These are grouped in uniform classes and weighted by the attribution of scores in order to assess the so-called "quality indexes". By computation of the previous indexes, "desertification indicators" are defined. This work reviews the most-used methodologies and presents an application of the methodology proposed in the European MEDALUS project to an area of the Calabrian territory (southern Italy), relative to the physical aspects. 1469 Landscape change and sandy desertification in arid areas: A case study in the Zhangye Region of Gansu Province, China Luo F., Qi S.Z. and Xiao H.L. Environmental Geology 2005 49/1 (90-97) The Zhangye Region of Gansu Province is an important agricultural base in arid northwestern China. During the twentieth century, especially in the last five decades, the region has experienced sandy desertification. To document the status and causes of this deterioration, satellite images, meteorological and socioeconomic data to assess landscape change from 1993 to 2002 were interpreted and analyzed. The results show that during the intervening 9-year period the area of sandy lands has increased by 642.2 km2 , which consist of aeolian sand dune (357.1 km2 ) and potential sandy land (216.3 km 2 ). Although the development and reversion of sandy desertification co-exist, the sandy desertification in this area seems serious and is attributable to the irrational use of water and land. © Springer-Verlag 2005. THE QUATERNARY Chronology 1470 Lower Azilian at Cueva Oscura de Ania (Las Regueras, Asturias, Spain) (French) (L’Azilien ancien de Cueva Oscura de Ania (Las Regueras, Asturias, Espagne)) ´ Ad´an Alvarez G.E., Garca S´anchez E. and Quesada L´opez J.M. Anthropologie 2005 109/3 (499-519) Recent definition of the Cantabrian Lower Azilian has turned the Late Upper Magdalenian/Azilian transition into one of the most interesting archaeological ages in the area. This period is considered representing the earliest Azilian groups in Asturias. Critic review of Cueva Oscura de Ania record, in the center of Asturias, has allowed us to give full details of the Lower Azilian archaeological characteristics. Cueva Oscura de Ania archaeological collection shows archaic traits, close to those from Cueva de Los Azules and Cueva de La Riera, two eastern asturian sites. These likenesses suggest a high stylistic and technical uniformity in distant areas during a critical period, when Palaeolithic groups changed their subsistence strategies. Cueva Oscura de Ania archaeological and polinic records suggest that this deposit was built at the beginning of the paleoclimatic phase known as Aller¨od/ Cantabrian VIII (12 000-10 800 BP), when numerous cantabrian sites suffered high erosion processes. All these circumstances convert Cueva Oscura de Ania in a fundamental site to get a best knowledge of the origin and development of the Cantabrian Azilian. The study of its bone collection allows us outline new hypothesis about this archaeological period. © 2005 Publi´e par Elsevier SAS. 1471 Norwegian conifer chronologies constructed to date historical timber Thun T. Dendrochronologia 2005 23/2 (63-74) Tree-ring chronologies have been constructed for Scots pine (Pinus sylvestris L.) from central Norway (Trøndelag), west Norway and south-east Norway back to 552, 765 and 871, respectively. The purpose was to enable the dendrochronological dating of medieval and post-medieval timber constructions and other wooden artefacts, and this proved to be possible. Absolute dates of floating chronologies based on medieval building material from urban excavations in Trondheim, Bergen and Oslo were also obtained. In northern Norway, samples taken from recently living Scots pines in Troms have enabled the construction of a chronology back to 1294. Chronologies based on samples taken from timber constructions built of Norway spruce (Picea abies (L.) Karst.) have been constructed for central Norway (Trøndelag) and outer Oslofjord back to 1351 and 1466, respectively. Historical events have influenced the availability of building timber. Although much material is available from the early and post-medieval periods, hardly any constructions have been found dating from an approximately 60-year period after the Black Death in 13491350. The various regional chronologies based on Scots pine have a matching tree-ring pattern with high t values and sign tests at a 99.9% level of significance. The match between Norwegian chronologies and chronologies constructed in Sweden also give high t values and sign tests at a 99.9% level of significance. © 2005 Elsevier GmbH. All rights reserved. 1472 Radiocarbon evidence for annual growth rings in the deep-sea octocoral Primnoa resedaeformis Sherwood O.A., Scott D.B., Risk M.J. and Guilderson T.P. Marine Ecology Progress Series 2005 301/- (129-134) The deep-sea gorgonian octocoral Primnoa resedaeformis is distributed throughout the Atlantic and Pacific Oceans at depths of 65 to 3200 m. It has a 2-part skeleton of calcite and gorgonin. Towards the inside of the axial skeleton gorgonin and calcite are deposited in concentric growth rings, similar to tree rings. Colonies were collected from the NE Channel (NW Atlantic Ocean, southwest of Nova Scotia, Canada) from depths of 250 to 475 m. Radiocarbon was measured in individual rings isolated from sections of each colony, after dissolution of calcite. Each 14 C measurement was paired with a ring age determined by 3 amateur ring counters. The precision of ring counts averaged better than 2 yr. Accurate reconstruction of 20th century bomb-radiocarbon showed that (1) the growth rings are formed annually, (2) the gorgonin is derived from surface particulate organic matter (POM) and (3) useful environmental data are recorded in the organic endoskeletons of deep-sea octocorals. These results support the use of P. resedaeformis as a long-term, high resolution monitor of ocean surface conditions, particularly in temperate and boreal environments where proxy data are lacking. © Inter-Research 2005. THE QUATERNARY 1473 Characteristics and sources of tephra layers in the EPICA-Dome C ice record (East Antarctica): Implications for past atmospheric circulation and ice core stratigraphic correlations Narcisi B., Petit J.R., Delmonte B. et al. Earth and Planetary Science Letters 2005 239/3-4 (253-265) Thirteen discrete air-fall tephra layers were identified in the last 200,000-yr section of the EPICA-Dome C ice record drilled in the East Antarctic plateau (75°06 S, 123°21 E). Quantitative grain size, glass particle morphology, and the grain-discrete major element composition of the glass fraction of these layers were investigated. Through comparison with literature data on the rock composition of Quaternary volcanic centres located within and around Antarctica, five tephra layers were attributed to South Sandwich volcanoes in the South Atlantic Ocean, two to South Shetland volcanoes (northern Antarctic Peninsula), two to Andean volcanoes, and four to Antarctic (Marie Byrd Land and Melbourne) provinces. The abundance of layers originating in the southern part of the Atlantic confirms that westerly atmospheric circulation spiralling towards East Antarctica prevailed over the last 200 ka. Moreover, the record of events from Antarctic centres suggests that atmospheric trajectories from West to East Antarctica can also be significant. A few ash layers are geochemically distinct and appear equivalent to levels from Vostok and Dome Fuji deep ice records, located ca. 600 km and ca. 2000 km, respectively, from Dome C on the Antarctic plateau. These layers provide unambiguous markers for future correlation with other Antarctic ice cores and circumpolar marine climatic records. They also provide reliable constraints to get a common timescale by glaciological modelling, and represent a first step towards absolute ice core dating. © 2005 Published by Elsevier B.V. 1474 First dating of protohistorical forest clearings on the Vosges grasslands (Rossberg, Haut-Rhin, France). A pedoanthracological study (French) (Premi`eres datations directes de d´efrichements protohistoriques sur les chaumes secondaires des Vosges (Rossberg, Haut-Rhin). Approche p´edoanthracologique) Schwartz D., Thinon M., Goepp S. et al. Comptes Rendus Geoscience 2005 337/14 (1250-1256) The age of the upland grasslands of the Vosges Mountains is still not well known. On the basis of the study of historical archives, it was assumed that the forest clearings, which led to grasslands establishment, were done by the monks who colonized the Vosges valleys between the 7th and the 8th centuries. Our pedo-anthracological study raises questions about this hypothesis, based on the discovery of Juniperus communis charcoal in soils from the 2nd or 1st century BC. This plant specie is characteristic of grasslands developing into fallows. The occurrence of Juniperus communis charcoals indicates that upland grasslands did exist at least 800 years earlier than it was expected before our study, i.e. at least since the late Iron Age. © 2005 Acad´emie des sciences. Publi´e par Elsevier SAS. Tous droits r´eserv´es. 1475 The age of the Paludi Formation: A major constraint to the beginning of the Apulia-verging orogenic transport in the northern sector of the Calabria-Peloritani Arc Bonardi G., De Capoa P., Di Staso A. et al. Terra Nova 2005 17/4 (331-337) A stratigraphic revision of the Paludi Formation, cropping out in Northern Calabria on the north-eastern side of Sila Massif, has confirmed that it has been deposited between two main tectonic phases. Actually the formation is involved only by top to the north-east thrusts, different from those separating the crystalline and ophiolitic nappes of Northern Calabria, and rests unconformably on the Sila Unit, the uppermost nappe of the tectonic stack. In the frame of the interpretation of Northern Calabria as a fragment of the Alps, the Paludi Formation play the role of a deposit post-dating the eo-alpine tectonic phases and pre-dating the Apenninic orogenic transport. Therefore the Aquitanian age of the formation, obtained by nannofloras analyses, can be considered the minimum age to the Apuliaverging orogenic transport, witnessed by top to north-east thrusts. It fairly corresponds to the age referred to the Lucanian ocean closure. © 2005 Blackwell Publishing Ltd. 279 1476 Pleistocene geomorphology and geochronology of eastern Grand Canyon: Linkages of landscape components during climate changes Anders M.D., Pederson J.L., Rittenour T.M. et al. Quaternary Science Reviews 2005 24/23-24 (2428-2448) We report new mapping, soils, survey, and geochronologic (luminescence, U-series, and cosmogenic-nuclide) data from Pleistocene deposits in the arid setting of eastern Grand Canyon. The result is a stratigraphic framework of inset fill gravels and associated terraces that provide a record of the responses of hillslopes, tributary streams, and the Colorado River to the last 400 kyr of glacial-interglacial climate change. The best-preserved last 80 kyr of this record indicates a stratigraphic-chronologic disconnect between both deposition and incision along the Colorado River versus along the trunks of local tributaries. For example, the Colorado River finished aggrading and had already begun incising before the main pulse of aggradation in the trunks of local catchments during Marine Isotope Stage 3, and then tributary incision followed during the millennial-scale fluctuations of the last glacial epoch, potentially concurrent with mainstem aggradation. The mainstem record appears to broadly correlate with regional paleoclimate and upstream geomorphic records and thus may be responding to climatic-hydrologic changes in its mountain headwaters, with aggradation beginning during full-glacial times and continuing into subsequent interglacials. The contrasting lag time in responses of the dryland catchments within Grand Canyon may be largely a function of the weathering-limited nature of hillslope sediment supply. © 2005 Elsevier Ltd. All rights reserved. 1477 Development of an OSL chronology for Late Pleistocene channel belts in the lower Mississippi valley, USA Rittenour T.M., Goble R.J. and Blum M.D. Quaternary Science Reviews 2005 24/23-24 (2539-2554) The broad alluvial valley of the lower Mississippi River contains large channel belts for which age control has been limited by the lack of organic material for radiocarbon dating and deposit ages greater than the limit of radiocarbon. In order to produce a detailed chronology of fluvial evolution, samples for optical dating were collected from Late Pleistocene channel-belt deposits. Quartz sand was analyzed using the coarse-grained, singlealiquot regenerative-dose (SAR) technique. Samples showed little evidence of partial bleaching, and optical ages are for the most part consistent with the available radiocarbon and relative age constraints. Optical ages range from 85 to 11 ka and, along with geomorphic and stratigraphic relationships, indicate that the Mississippi River was meandering during the end of the last interglacial (85-83 ka) and switched to a braided regime by 64-50 ka during initial marine oxygen isotope stage (OIS) 4/3 glaciation of the upper Mississippi drainage basin. The Mississippi River switched back to a meandering regime after formation of the youngest braid belt at 11 ka. The 69 optical ages presented here provide the first detailed chronology of lower Mississippi valley braid-belt and Pleistocene meander-belt formation, and provide an example of the utility of optical dating in fluvial settings where material for radiocarbon dating is scarce. © 2005 Elsevier Ltd. All rights reserved. 1478 Isotopic fractionation during leaching of impure carbonates and their effect on uranium series dating Alcaraz Pelegrina J.M. and Martnez- Aguirre A. Quaternary Science Reviews 2005 24/23-24 (2584-2593) Experiments were designed to evaluate the behaviour of detritus during the leaching of impure carbonates by applying the U-Th isochron technique. We used one natural detritus and a pure, well-dated CaCO3 , alone and in artificial mixtures. One set of experiments was designed to study the effects of sample pretreatment on the detritus and a second set to examine the effect of acid attacks on both the carbonate and the detritus fractions in a mixture of constant proportions. For both sets of data, the extracted fraction from the detritus was calculated for 238 U, 234 U, 230 Th and 232 Th and their constancy established. These conditions are necessary to apply the L/L method [Schwarcz, H.P., Latham, A.G., 1989. Dirty calcites. 1.-Uranium-series dating of contaminated calcite using leachates alone. Chemical Geology (Isotopes Geoscience Section) 80, 35-43] for U/Th dat- 280 THE QUATERNARY ing. Finally, the L/L method was applied to the artificial impure carbonate and the resulting age is found in agreement with the age of the pure carbonate sample. We concluded that conditions of the L/L method to be applied for ageing impure carbonates hold. © 2005 Elsevier Ltd. All rights reserved. 1479 In situ U-series dating by laser-ablation multi-collector ICPMS: New prospects for Quaternary geochronology Eggins S.M., Gr¨un R., McCulloch M.T. et al. Quaternary Science Reviews 2005 24/23-24 (2523-2538) The capabilities and potential applications of in situ dating of Quaternary materials using laser ablation-MC-ICPMS are explored. 234 U/ 238 U and 230 Th/234 U can be measured with precision sufficient for dating at a spatial resolution of 100 m or better in samples that contain as a little as 1 ppm uranium. Moreover, U and Th concentrations and U-series isotope ratios can be continuously profiled to determine changes in age that occur with sample growth (e.g. in speleothems). These capabilities additionally permit the dating of bones, teeth and possibly molluscs, which are subject to post-mortem open-system behaviour of U-series isotopes, and can be employed to elucidate processes of U-series migration during weathering and diagenesis. A drawback of laser ablation-MC-ICPMS is that it cannot in general provide U-series age estimates with the high precision and accuracy of conventional TIMS or solution MC-ICPMS methods. However, sample preparation is straightforward, the amount of sample consumed negligible, and it can be used to rapidly characterise or screen and select samples from which more precise and accurate dates can be obtained using conventional methods. Given further instrumental developments and the establishment of suitable matrix-matched standards for carbonates and other materials, we foresee that laser ablation-MC-ICPMS will play an increasingly important role in Quaternary dating research. 1480 A middle Pleistocene mollusc fauna from a borehole in Northern Oberrheingrabens (Bohrung Mannheim-Lindenhof) (German) (Eine mittelpleistoz¨ane Molluskenfauna aus dem Oberen Zwischenhorizont des n¨ordlichen Oberrheingrabens (Bohrung Mannheim-Lindenhof)) R¨ahle W. Mainzer Geowissenschaftliche Mitteilungen 2005 -/33 (9-20) Upper layer sediments from the so-called "Oberer Zwischenhorizont" obtained from boreholes in the Mannheim area of the Upper Rhine Graben yielded quite a diverse mollusc fauna dating from a Middle Pleistocene interglacial. The occurence of extinct taxa like Parafossarulus crassitesta and Clausilia rugosa antiquitatis is biostratigraphically important and so are the finds of molars of an early representative of the vole Arvicola terrestris. Judging from these fossil remains the age of the investigated section is unlikely to be younger than Cromer-Interglacial IV (OIS 13), yet not older than Cromer-Interglacial III (OIS 15). An Upper Pleistocene age (Eemian) should, no doubt, be excluded. 1481 ESR dating of glacial tills and glaciations in the Urumqi River headwaters, Tianshan Mountains, China Zhao J., Zhou S., He Y. et al. Quaternary International 2005 144/1 (61-67) Electron spin resonance (ESR) dating of the Shangwangfeng, the Xiawangfeng, and the Gaowangfeng tills in the headwaters of the Urumqi River was carried out using Ge centers in quartz grains. The Shangwangfeng till is dated at 35 3.5 ka BP. Three dates from the lower portion of the Xiawangfeng till are 171.1 17, 176 18, and 184.7 18 ka BP, respectively, and the age of the Gaowangfeng till is 459.7 46 ka BP. Considering the available ages (i.e. 14 C, TL and ESR) and the principles of geomorphology and stratigraphy, the Shangwangfeng till is determined to be deposited in marine isotopic stage 2-3 (MIS2-3). The upper part of the Xiawangfeng till was formed in MIS4 and the lower part was deposited in MIS6. The Gaowangfang till is the oldest at the head of the Urumqi River, corresponding to MIS12. The age of the Gaowangfang till also demonstrates that the Tianshan Mountains lay at a suitable altitude for a glacial climate at that time, when the glaciers on this segment of the mountain began to develop. © 2005 Published by Elsevier Ltd. Palaeoclimatology 1482 Pervasive and long-term forcing of Holocene river instability and flooding in Great Britain by centennial-scale climate change Macklin M.G., Johnstone E. and Lewin J. Holocene 2005 15/7 (937-943) This paper presents the first probability-based record of flooding in Europe that spans the entire Holocene. An analysis of 506 14 C dated fluvial units collected across the whole of Great Britain provides a novel and robust methodology for improving flood risk assessment by geographically and temporally extending the record of extreme flood events. Sixteen episodes of increased flooding occurrence are identified, 12 of which (at c. 11 160, 5730, 4840, 4520, 3540, 2730, 2550, 2280, 1950, 1290, 660, 570, cal. BP) are recorded in most regions, whereas four phases (at c. 6820, 5540, 1650, 860 cal. BP) affected some parts of Great Britain more than others. In all regions large variations in flood frequency and magnitude occurred before forest clearance and indicate an underlying climatic control. During the mid-Holocene there is evidence for a hydroclimatic ‘system switch’, which in terms of catchment hydrology in Great Britain was marked by two sudden increases in both the frequency and severity of floods at c. 5000 cal. BP and, most notably, at c. 3000 cal. BP. The marked non-stationary behaviour of the British flood series at these times reflects a regional hydrologic response to large-scale ocean-atmospheric circulation changes superimposed on a pattern reflecting both long-term land-use change and the preferential preservation of later fluvial units. Centennial-scale variations in the occurrence of extreme flood events in Great Britain appear to be a sensitive indicator of past and present climate change in the North Atlantic region. © 2005 Edward Arnold (Publishers) Ltd. 1483 Holocene climate evolution in the high-latitude Southern Hemisphere simulated by a coupled atmosphere-sea iceocean-vegetation model Renssen H., Goosse H., Fichefet T. et al. Holocene 2005 15/7 (951-964) The Holocene climate is simulated in a 9000-yr-long transient experiment performed with the ECBilt-CLIO-VECODE coupled atmosphere-sea ice-ocean-vegetation model. This experiment is forced with annually varying orbital parameters and atmospheric concentrations of CO2 and CH 4 . The objective is to study the impact of these long-term forcings on the surface temperature evolution during different seasons in the high-latitude Southern Hemisphere. We find in summer a thermal optimum in the midHolocene (6-3 ka BP), with temperatures locally 3°C above the preindustrial mean. In autumn the temperatures experienced a long-term increase, particularly during the first few thousand years. The opposite trend was simulated for winter and spring, with a relatively warm Southern Ocean at 9 ka BP in winter (up to 3.5°C above the preindustrial mean) and a warm continent in spring (+3°C), followed by a gradual cooling towards the present. These long-term temperature trends can be explained by a combination of (1) a delayed response to orbital forcing, with temperatures lagging insolation by 1 to 2 months owing to the thermal inertia of the system, and (2) the long memory of the Southern Ocean. This long memory is related to the storage of the warm late winter-spring anomaly below the shallower summer mixed layer until next winter. Sea ice plays an important role as an amplifying factor through the ice-albedo and ice-insulation feedbacks. Our experiments can help to improve our understanding of the Holocene signal in proxies. For instance, the results suggest that, in contrast to recent propositions, teleconnections to the Northern Hemisphere appear not necessarily to explain the history of Southern Hemisphere temperature changes during the Holocene. © 2005 Edward Arnold (Publishers) Ltd. 1484 Ice caves as an indicator of winter climate evolution: A case study from the Jura Mountains Luetscher M., Jeannin P.- Y. and Haeberli W. Holocene 2005 15/7 (982-993) Subsurface ice fillings were first described in the Jura Mountains at the end of the sixteenth century. In order to assess the impact THE QUATERNARY of climate change on low-altitude cave ice a detailed inventory has been drawn up and more than 50 objects have been identified. Comparisons between older cave maps, photographic documents and present-day observations outline a negative trend in ice mass balances, a trend that increased at the end of the 1980s. As most of these ice caves act as cold air traps, this negative mass balance is mainly attributed to higher winter temperatures and to reduced snow precipitation at low altitudes. The equilibrium line altitude of ice caves is believed to have increased several hundred metres between AD 1978 and 2004. Photographic comparisons and proxy records in some of the caves studied provide evidence of a rapid mass turnover. Ice ages range between less than a few decades and a millennium. Climatic records in these ice fillings will therefore present only short time series compared with other cave sediments. However, indications of former ice fillings have been found in different caves of the Jura Mountains and outline their potential role as palaeoclimatic markers. © 2005 Edward Arnold (Publishers) Ltd. 1485 Vegetation and fire history since the Late Pleistocene from the Trinity Mountains, northwestern California, USA Daniels M.L., Anderson R.S. and Whitlock C. Holocene 2005 15/7 (1062-1071) A 267-cm sediment core spanning the past c. 15 200 cal. yr was recovered from Mumbo Lake, in the Trinity Mountains of northwestern California’s Klamath Region. Plant macrofossils and pollen detail local and extra-local vegetation history, while high-resolution charcoal analysis provides details on local fire history. For the first c. 3000 years, climate was colder and drier than present, and supported an open, subalpine parkland vegetation, with low fire frequencies and fuel biomass. From c. 12 100 to 9800 cal. yr BP increasing moisture and soil development led to a woodland community with three new pine species invading the basin. Fire frequencies remained low, but individual fires may have been more intense because of increased fuel loads. Between c. 9800 and 7200 cal. yr BP, climate warmed and dried considerably, allowing for the expansion of oak and other chaparral species. Fire frequencies increased in the early Holocene, but low charcoal accumulation rates suggest a frequent, relatively low-intensity fire regime. From c. 7200 to 3800 cal. yr BP, the climate became cooler and moister again. Many conifer species appeared for the first time, although chaparral species maintained a strong presence. The fire record shows a dramatic increase in charcoal accumulation rates as well as an increase in fire frequency. From c. 3800 cal. yr BP to present, more conifer species enter the record, and abundance of chaparral species gradually diminishes to present levels. © 2005 Edward Arnold (Publishers) Ltd. 1486 Standardized precipitation index reconstructed from Turkish tree-ring widths Touchan R., Funkhouser G., Hughes M.K. and Erkan N. Climatic Change 2005 72/3 (339-353) May-July Standardized Precipitation Index (SPI) for the land area of most of Turkey and some adjoining regions are reconstructed from tree rings for the period 1251-1998. The reconstruction was developed from principal components analysis (PCA) of four Juniperus excelsa chronologies from southwestern and southcentral Turkey and is based on reliable and replicable statistical relationships between climate and tree ring growth. The SPI reconstruction shows climate variability on both interannual and interdecadal time scales. The longest period of consecutive drought years in the reconstruction (SPI threshold -1) is 2 yr. These occur in 1607-1608, 1675-1676, and 1907-1908. There are five wet events (SPI threshold +1) of two consecutive years each (1330-1331, 1428-1429, 1503-1504, 1629-1630, and 19131914). A 5-yr moving average of the reconstructed SPI shows that two sustained drought periods occurred from the mid to late 1300s and the early to mid 1900s. Both episodes are characterized by low variability. © Springer 2005. 1487 Vegetation changes during the past 1300 years in western equatorial Africa: A high-resolution pollen record from Lake Kamal´et´e, Lop´e Reserve, Central Gabon Ngomanda A., Chepstow- Lusty A., Makaya M. et al. Holocene 2005 15/7 (1021-1031) Vegetation changes during the past 1300 years are reconstructed 281 in western equatorial Africa using a high-resolution pollen record from Lake Kamal´et´e. This small marshy basin (c. 5-7 ha) is located in forest-savanna mosaic in Lop´e Reserve (0°43’S, 11°46’E), central Gabon. The Kamal´et´e pollen data show the persistence over the past 1300 years of a relatively stable forestsavanna mosaic, associated with significant changes of the forest component. Three successive stages of forest dynamics occurred. First, at 1325 cal. BP, moist semi-evergreen rainforest existed around the catchment of Lake Kamal´et´e. However, it appears from the consistent presence of > 70% Gramineae pollen that the site was always primarily in savanna. Secondly, from c. 1240 to 550 cal BP, a noticeable increase in shade-intolerant plant species indicate openings in the rainforest canopy. The persistence of gap-colonizer species, such as Macaranga, Tetrorchidium and Musanga for several centuries in the rainforest, is explained by recurring canopy disturbance associated with shifts in available moisture. These hydrological changes may be related to a succession of longer and more severe dry seasons than observed today. Thirdly, at 550 cal BP, mature forest was re-established, corresponding to progressive savanna colonization by forest pioneer species such as Aucoumea klaineana, Lophira alata and Fagara macrophylla. This new phase of forest expansion coincided with a marked lithological change, indicating an increase in lake-level. It is concluded that the major vegetation changes observed are due to climatic variability, and anthropogenic action had limited influence. © 2005 Edward Arnold (Publishers) Ltd. 1488 Complex speleothem growth processes revealed by trace element mapping and scanning electron microscopy of annual layers Treble P.C., Chappell J. and Shelley J.M.G. Geochimica et Cosmochimica Acta 2005 69/20 (4855-4863) Closely-spaced transects measured by excimer laser ablation inductively-coupled plasma mass spectrometry (ELA-ICPMS) at 5 and 32 m spatial resolution are used to generate trace element composition maps (Ba, Sr, Mg, U, Na, P and Al) from MND-S1, a previously studied modern stalagmite from southwest Australia (Treble et al., 2003 1). Rainfall at the site is highly seasonal, and trace elements in MND-S1 show strong seasonal variation. Trace element maps show that Ba, Sr, U and Na concentrations coherently follow annual growth layers identified from Scanning Electron Microscopy (SEM) images. The SEM images also reveal that stalagmite growth did not proceed uniformly: growth layers vary in thickness and locally pinch out. Highly preferential crystal growth, determined by nucleation sites left by the previous year’s growth, may be responsible for this uneven growth layering. Differential crystal growth apparently causes variability of trace element concentrations along each annual layer, although additional disequilibrium processes affect Mg, which is less distinctly banded than Ba, Sr, U and Na. Uneven and discontinuous growth layers influence the number of annual cycles, their wavelengths and seasonal amplitudes measured in any one transect. This has clear implications for studies that use annual trace element cycles as chronological markers, growth rate or seasonality proxies. Copyright © 2005 Elsevier Ltd. 1489 Palaeoclimatology and palaeohydrography of the glacial stages on Celtic and Armorican margins over the last 360 000 yrs Mojtahid M., Eynaud F., Zaragosi S. et al. Marine Geology 2005 224/1-4 (57-82) Core MD03-2692 was retrieved in a water-depth of 4064 m on the Celtic margin (Bay of Biscay) during the SEDICAR cruise onboard the RV Marion Dufresne II. It covers the last 360 ka in a total length of 39 m. Multidisciplinary analyses have been applied to this sequence with the aim of studying the palaeoclimatic and palaeoenvironmental signals of the last few climatic cycles. The analyses undertaken include: (1) non-destructive logging with: physical properties (magnetic susceptibility, sediment colour), X-ray radiography and measurement of the major elements by X-ray-fluorescence, (2) analyses of planktonic and benthic foraminifera, lithic grains and stable isotopic measurements (oxygen and carbon). We have focused on the long-term evolution of glacial stages (with special attention to terminations and Heinrich events). The results obtained confirm the close correlation between deep-sea sedimentation recorded on the Celtic 282 THE QUATERNARY margin and changes in the terrestrial environment of the adjacent continent. Heinrich layers have been identified in MIS 2, 3, 6 and 8. We note the occurrence of laminated facies within deglacial sequences deposited during Termination I and MIS 6. These facies are closely linked to disintegration phases of the British-Irish Ice Sheet (BIS). The laminations contain lower ice-rafted detritus (IRD) concentrations than the equivalent Heinrich layers and are linked to abrupt changes in sea-surface palaeotemperatures. We suggest that the laminations are formed by an annual cycle of meltwater and iceberg release from the disintegrating BIS generating cascading plumes of dense turbid meltwater coeval with IRD release. © 2005 Elsevier B.V. All rights reserved. 1490 Last interglacial atmospheric CO2 changes from stomatal index data and their relation to climate variations Rundgren M., Bj¨orck S. and Hammarlund D. Global and Planetary Change 2005 49/1-2 (47-62) A high-resolution atmospheric CO2 reconstruction based on stomatal index data obtained from Betula and Quercus leaf fragments extracted from the Danish Hollerup lake sediment section provides a unique insight into last interglacial CO2 dynamics. According to pollen stratigraphic correlations the CO2 record covers the first c. 7400 years of the Eemian, as palaeobotanically defined in northwestern Europe. The first c. 3000 years of the reconstruction are characterised by centennial to millennial CO2 variability in the interval 250-290 ppmv, while the remaining part of the record is generally more stable with slightly higher values (290-300 ppmv). According to pollen stratigraphic correlations this shift in CO 2 dynamics is coincident with the end of the early Eemian climatic optimum in northwestern Europe. Pollen data from this region indicate that early Eemian CO2 instability may be linked to vegetation succession following deglaciation in Europe, but vegetation dynamics on other northern continents were probably also important. In addition, palaeoceanographic records from the Nordic seas indicate an influence of oceanic processes on the reconstructed Eemian CO2 evolution. A 300-year period of rapid CO2 oscillations immediately before the establishment of stable conditions is synchronous with a dry and cool event previously inferred from proxy data from the same sediment sequence, suggesting that this was a climatic event of regional or global significance. The presented CO2 reconstruction is in general agreement with previous ice core and stomatal-based CO2 data, although a larger variability compared with Vostok ice core data is evident. This may be explained partly by the different resolution of the two records and the inherent smoothing of ice core gas records. © 2005 Elsevier B.V. All rights reserved. 1491 Mid-Holocene strengthening of the Southern Westerlies in South America - Sedimentological evidences from Lago Cardiel, Argentina (49°S) Gilli A., Ariztegui D., Anselmetti F.S. et al. Global and Planetary Change 2005 49/1-2 (75-93) The paleoclimatic evolution of southern South America is characterized to a large extent by the behavior (strength and latitudinal position) of the storm tracks of the Southern Westerlies. Our study site, Lago Cardiel (49°S), lies within the modern influence of the Southern Westerlies and, therefore, is ideally located to track the past migrations of these storm tracks. With a coring strategy taking into account the lateral differences in sedimentation and an excellent core-to-core correlation using tephra layers, a composite sedimentological record of almost 25 m was established covering the last 16,000 cal yr. Sedimentological and petrophysical analysis of the cores revealed the establishment of a dominant lake current since 6800 cal yr BP leading to a drift deposition, which is especially well-expressed in the sedimentary record by an increase in magnetic susceptibility values. As this pattern of currents is most likely induced by wind activity, we propose that the observed increase in magnetic susceptibility documents an intensification of the westerly storm tracks. This intensification occurred slightly earlier than previously suggested based on palynological evidence. The strengthening in the Southern Westerlies during the mid-Holocene is most likely caused by an increase in the temperature gradient as a result of enhanced influence and/or southward migration of the Southeast Pacific anticyclone and a larger Antarctic sea-ice extent. © 2005 Elsevier B.V. All rights reserved. 1492 Late Pleistocene vegetation of the basin of Phlious, NE-Peloponnese, Greece Urban B. and Fuchs M. Review of Palaeobotany and Palynology 2005 137/1-2 (15-29) Results of sedimentological and palynological analyses and 14 C dating of organic lake sediments of a transect through the basin of Phlious, west-southwest of Corinth (NE-Peloponnese, Greece) are presented. They provide a record of five moist and temperate phases, rich in predominantly deciduous Quercus and Pinus with minor representation of other deciduous and evergreen trees including evergreen oak and shrubs, interrupted by five drier and cooler episodes including Heinrich event (HE) 5, during a period of relatively high but fluctuating lake levels within Marine Isotope Stage 3 (MIS 3). The youngest interstadial of the Pleistocene pollen sequence is correlated with GRIP Greenland Interstadial 9 (GI9) with a calibrated age of around 40,000 years BP (14 C 34,440 yrs BP). In the uppermost part of the Pleistocene sequence the occurrence of HE 4 is rather probable. This initial Pleistocene record from southern Greece is compared with those from central Greece to provide a regional synthesis of vegetation and climatic variation during this part of the last glacial period. © 2005 Elsevier B.V. All rights reserved. 1493 Pre-industrial metal anomalies in ice cores: A simplified reassessment of windborne soil dust contribution and volcanic activity during the last glaciation Oyarzun R., Lillo J., S´anchez- Hern´andez J.C. and Higueras P. International Geology Review 2005 47/11 (1120-1130) A major issue regarding pre-industrial accumulation of heavy metals such as Cu, Ph, Zn, or Hg in ice cores relates to the source(s) of the metals. We investigate the two possibilities that have been generally advocated for the origin of metal anomalies: (1) increased amounts of windborne dust during particularly cold periods; and (2) volcanic activity. We analyze the time span 35,000-14,000 yrs BP, which is characterized by extreme temperature deviations ( T;-2.1° to -9.8°C). Our findings show no definitive relationships between climate, dust, and metal contents, at least during the colder episodes. Thus, although dust deposition undoubtedly adds metals to the ice, it not clear whether climate can fully account for a direct relationship between these variables. In order to study the volcanic hypothesis, we analyze the case under a double perspective: (1) large explosive episodes related to acid magmatism; and (2) quieter mafic volcanic activity. Although the first one can introduce huge volumes of metal-rich aerosols to the stratosphere during single, catastrophic events, the latter is more continuous, accumulative, and far richer in sulfur. However, inasmuch as metals build volatile species with sulfur and halides, the chloride-rich character of the acid volcanism could easily compensate for its deficiency in sulfur. Thus, we suggest that the volcanic activity, via quiescent degassing and eruptive episodes, may account for an important part of the heavy metal contents present in the ice cores. Copyright © 2005 by V. H. Winston & Son, Inc. All rights reserved. 1494 Oxygen isotopic evidence for greater seasonality in Holocene shells of Donax variabilis from Florida Jones D.S., Quitmyer I.R. and Andrus C.F.T. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (96-108) Donax variabilis, the variable coquina clam, has been a common inhabitant of exposed sandy beach intertidal and shallow subtidal zones in the southeastern United States throughout the Pleistocene and Holocene. It is ideally suited for paleotemperature studies because it is restricted to environments of well-mixed, normal-marine seawater with a fairly uniform isotopic composition. As a result, oxygen isotopic variability in D. variabilis shells is largely explained by temperature variation. Although D. variabilis is small and short-lived, its shell represents an important paleoclimate archive because of its unique habitat preference. High-resolution sampling of individual D. variabilis shells and comparison of oxygen isotopic temperature profiles with historical seawater temperatures from the northeastern Florida coast indicate rapid shell growth over a brief life span of three to five or six months. Analysis of two modern shells reveals a close correspondence between isotopically determined water temperatures and historical water temperatures during the springsummer growing season. Paleotemperature profiles from four THE QUATERNARY archaeological shells, however, suggest a longer growth interval spanning summer-autumn. Two Preceramic Archaic Period shells (ca. 4240 and 5570 14 C yr BP) and two Orange Period Archaic shells (ca. 3600 and 3760 14 C yr BP), from four different archaeological sites, yield paleotemperatures that average 3.5°C higher than present summer-autumn water temperatures. These warm paleotemperatures highlight seasonality differences associated with the mid-Holocene Hypsithermal climatic interval in this region. © 2005 Elsevier B.V. All rights reserved. 1495 Climate records from a bivalved Methuselah (Arctica islandica, Mollusca; Iceland) Sch¨one B.R., Fiebig J., Pfeiffer M. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (130-148) We measured annual shell growth rates of a 374-year-old (radiometrically confirmed) bivalve mollusk specimen of Arctica islandica (Linnaeus). This bivalve represents the oldest ever reported individual animal. In addition, we analyzed 1051 individual powder samples from ontogenetic years two to 40 (= 80% of the entire shell height) for isotope analyses. Oxygen and carbon isotopes exhibit clear intra-annual cycles. The highest measured carbon isotope values (on average + 2.73‰) occurred during summer, i.e., during maximum primary productivity. The 18 Oaragonite -derived temperature time-series cover the period of AD 1496-1533. Temperatures calculated from oxygen isotopes ranged from 4.5 to 9.3°C and exhibit a mean value of 6.2°C. The latter coincides well with the 1854-2003 mean value of 6.81°C for sea-surface temperature between February and September (= growing season of A. islandica). Neither oxygen nor carbon isotopes exhibit age-related, unidirectional trends. However, 13 Caragonite and 18 Oaragonite values fluctuated at decadal periods of four, six and eight to nine years (NAO-type periods) as well as 12-14 years which may represent teleconnections to cycles in the tropical Atlantic. Annual shell growth is positively correlated to intra-annual 18 O aragonite minima, i.e., warm summer temperatures (R2 = 0.34), and to intra-annual 13 Caragonite minima (higher food supply; R2 = 0.42). Using a linear multiregression model, 65% of the variation in annual shell growth can be explained by summer temperature and food supply. The formation of extremely narrow annual increments coincides with major volcanic eruptions (e.g., Tambora 1815). A period of extremely variable growth occurred during the culmination of the Little Ice Age in Iceland between ca. AD 1550 and 1620. Shell growth during AD 1765-1780, however, was characterized by very little year-toyear variability, probably as the result of extremely mild climate near the end of the Little Ice Age. This study demonstrates that shells of A. islandica provide subseasonal to multidecadal, precisely dated multi-proxies of environmental variables from marine, mid to high latitudes. Such data can be used to validate and complement climate models and further assess human impact on climate and ecosystems. © 2005 Elsevier B.V. All rights reserved. 1496 Preserving low-frequency climate signals in growth records of geoduck clams (Panopea abrupta) Strom A., Francis R.C., Mantua N.J. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (167-178) The capacity of geoduck clams (Panopea abrupta) to preserve detailed records of climatic change in their shells is limited primarily by longevity. Unlike the multi-centennial growth records commonly available from trees, shells rarely yield more than 160 years of data; consequently low-frequency signals may be lost when band width series are processed. Here we investigate use of ‘Regional Curve Standardization’ (RCS) to preserve decadal to centennial-scale growth trends in the relatively short segment lengths available from individual clams. Advantages of this method over the more common ‘exponential’ treatment are first explored through simulation experiments using sine waves embedded in geoduck growth curves. Both standardization methods are then used to remove biological trends from growth records of geoduck shells sampled near Protection Island, in the Strait of Juan de Fuca. The resulting chronologies are compared in terms of their spectral properties, their correlations with historical air temperature records and their agreement with historical observations of the marine environment. Simulation experiments illustrated the potential benefits of using the RCS growth model to standardize shell growth series, but empirical results were 283 inconclusive. The RCS chronology exhibited enhanced spectral power at periods exceeding the length of growth segments, and provided stronger correlation with coastal air-temperature records, especially during the earliest portion of the chronology. Over the full period of comparison, however, the correlation coefficients were essentially identical. Observational data from the mid to late 1800s appears to support the RCS results. Northward range expansions of several marine fish species coincide with a period of conspicuously high values in the RCS chronology, and suggest that the coastal ocean was unusually warm along western North America from the 1850s through the 1870s. © 2005 Elsevier B.V. All rights reserved. 1497 Oxygen isotope composition of modern and archaeological otoliths from the estuarine hardhead catfish (Ariopsis felis) and their potential to record low-latitude climate change Surge D. and Walker K.J. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (179-191) Shells and otoliths (fish "ear bones") from archaeological deposits of Pine Island, southwest Florida, provide valuable archives of ecological patterns, climate change, and associated human responses. Many remains from these deposits that can be used for climate reconstruction are from estuarine animals. The challenge in using oxygen isotope composition of their carbonate hard parts lies in deconvoluting the effects of temperature and salinity (mixing of fresh- and saltwater, each having different isotopic compositions). Otoliths of the hardhead catfish (Ariopsis felis, Linneaus, 1766) may provide a record of winter temperature without the complication of salinity variation because this fish spends winter months in waters of marine to near-marine salinities. Hence, 18 OWATER can be constrained when employing published temperature equations. Here, we present geochemical data from modern and archaeological otoliths to evaluate whether they preserve winter temperature. A modern catfish was caught near Pine Island Sound and the otoliths (lapilli) removed. Archaeological otoliths from the 2nd/3rd century AD, falling within the Roman Optimum (RO), and the 13th/14th century AD, falling within the Little Ice Age (LIA), were obtained from the Florida Museum’s collections. Oxygen isotope compositions were converted to temperature using published temperature equations and assuming + 1‰ for Gulf water. Isotopic compositions for the modern otolith range from -3.55‰ to + 0.29‰, the LIA otolith ranges from -3.92‰ to + 0.52‰, and the RO otolith ranges from -1.80‰ to + 0.84‰. All three otoliths record winter temperature ( 20°C) similar to modern conditions. Calculated summer temperatures for the modern and LIA otoliths ( 40°C) are overestimated and reflect the combined influence of temperature and salinity when catfish inhabit brackish estuarine waters during their reproductive season. In contrast, summer temperature estimates for the RO otolith are similar to modern conditions indicating estuarine water during the summer was close to + 1‰. This result suggests that seasonal rainfall patterns during the time period represented by the RO otolith were different than today, such that the summer wet season was not prevalent. © 2005 Elsevier B.V. All rights reserved. 1498 Denitrification under glacial and interglacial conditions: A physical approach Meissner K.J., Galbraith E.D. and V¨olker C. Paleoceanography 2005 20/3 (1-13) Recent analysis of sedimentary 15 N records over the last 200,000 years has shown an expansion of water column denitrification zones during warmer periods and a shrinkage of these oxygenpoor regions during glacial periods. Two different mechanisms could be responsible for driving the changes in the denitrification records: variations in local productivity leading to a change in remineralization rates and/or changes in the ocean circulation and ocean temperature resulting in variations of the physical supply of dissolved oxygen. Here we focus on the "supply" mechanism by using a fully coupled atmosphere-ocean-sea ice-land surface scheme model (the University of Victoria Earth System Climate Model) to examine oxygen supply under varying physical conditions while maintaining an invariant biological oxygen utilization scheme. We show that circulation changes can be the cause for the observed changes in dissolved oxygen in the glacial ocean. Lower temperatures and enhanced formation of Antarctic Intermediate Water and North Pacific Intermediate Wa- 284 THE QUATERNARY ter during glacial periods increase the physical supply of oxygen and therefore decrease water column denitrification. In our Last Glacial Maximum simulations the change in water characteristics in the eastern tropical Pacific is important enough to reduce denitrification by 46% to 65% compared to present-day conditions, depending on the wind fields used as boundary conditions. The consequences of our findings could be substantial for the near future. With a warming climate, denitrification zones could expand, leading to changes in the biological pump and the flux of N2 O into the atmosphere. Copyright 2005 by the American Geophysical Union. 1499 Palaeoenvironmental changes in southern Patagonia during the last millennium recorded in lake sediments from Laguna Azul (Argentina) Mayr C., Fey M., Haberzettl T. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/3-4 (203-227) Marked environmental changes in the southern Patagonian steppe during the last 1100 years are detected by a multi-proxy study of radiocarbon-dated sediment cores from the crater lake Laguna Azul (52°05 S, 69°35 W). A prominent shift in carbon isotope records occurred between AD 1670 and AD 1890 induced by a change to cooler climate conditions with a concurrent lake level rise. A second perturbation of the lake ecosystem started with a fire event around AD 1830. The fire event triggered increased soil erosion initiating a change of the diatom assemblages. This shift in diatom assemblages may have been enhanced by shrinkage of littoral habitats and higher nutrient supply in the course of permanent European settlement at the end of the 19th century. The introduction of neophytes by European sheep farmers is confirmed by the permanent occurrence of Rumex pollen in the sediment record since the beginning of the 20th century. © 2005 Elsevier B.V. All rights reserved. 1500 The loess record from the section at Kurtak in Middle Siberia Frechen M., Zander A., Zykina V. and Boenigk W. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/3-4 (228-244) Loess, loess-like sediments and the intercalated palaeosols along the bluffs of the river Yenisei provide a detailed Upper Pleistocene climate archive for the southern part of Middle Siberia. The section at Kurtak is one of the most detailed loess/palaeosol sequences in Middle Siberia. Two major periods of sediment accumulation were recorded in the sequence: the stratigraphically oldest one post-dating the last interglacial palaeosol and pre-dating the Kurtak Pedocomplex (oxygen isotope stage (OIS) 3); the younger one post-dating the Kurtak Pedocomplex and predating the Holocene soil. Three major phases of soil formation occurred during the Upper Pleistocene. The Kameny Log Pedocomplex (OIS 5e) consists of at least two pedogenetic episodes, a lower clayey chernozem forming during a more humid and warmer climate than today, and an upper chernozem representing a drier climate than today, the latter one including a well-pronounced carbonate-rich horizon. The Sukhoy Log Pedocomplex consists of a chernozem-like palaeosol and two kastanozjems (OIS 5ca) and the Kurtak pedocomplex (OIS 3) with two chernozemlike palaeosols and up to three humic-rich layers. Additionally, weakly developed gleyed horizons are considered to represent palaeohydrological groundwater high levels. The results indicate a synchronous evolution of climate and environment change in both the more oceanic driven climate of West and Central Europe and Middle Siberia, as evidenced by luminescence dating results. © 2005 Elsevier B.V. All rights reserved. 1501 Temperature variations since the mid-18th century for western Nepal, as reconstructed from tree-ring width and density of Abies spectabilis Sano M., Furuta F., Kobayashi O. and Sweda T. Dendrochronologia 2005 23/2 (83-92) The climate of western Nepal was reconstructed for the past 249 years using ring width and wood density of Abies spectabilis (D. Don) Spach from western Nepal. A total of 46 increment core samples were collected from 23 individual trees growing in an open A. spectabilis stand near timberline of 3850 m a.s.l. in Humla District, western Nepal. The core samples were subjected to densitometric analysis to obtain chronologies of ring width and three kinds of intra-annual bulk densities, i.e., min- imum, maximum, and mean. Response analysis of tree-ring parameters with climate records revealed that the ring width was correlated negatively with March-May (pre-monsoon) temperature and positively with March-May precipitation, while the minimum density was correlated positively with March-July temperature and negatively with March-May precipitation. On the other hand, the maximum and mean densities were positively correlated with August-September and March-September temperatures, respectively. These results indicate that the ring width and minimum density are primarily controlled by the pre-monsoon temperature and precipitation, while the latewood density by the late monsoon temperature. Finally based on these results of the response analysis, a transfer function was established, with which March-September temperature was reconstructed for the past 249 years, which shows a warming trend from 1750s until approximately 1790, followed by cooling until 1810, then by a gradual warming trend extending to 1950, and a notable cold period continuing up to the present. No evidence of a consistent warming trend over the last century or two commonly appearing in higher latitudes was found in the present reconstruction, but possible factor behind the widespread glacial retreat in the Nepal Himalayas was discussed. © 2005 Elsevier GmbH. All rights reserved. 1502 Sediment sources and East Asian monsoon intensity over the last 450 ky. Mineralogical and geochemical investigations on South China Sea sediments Boulay S., Colin C., Trentesaux A. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/3-4 (260-277) A coupled approach based on clay mineral assemblages and isotopic data (Sr and Nd) of sediment from Ocean Drilling Program (ODP) Site 1145 has been used to trace the sources of sediment feeding the northern part of the South China Sea, and to investigate the evolution of East Asian monsoon intensity over the last 450 ky. Clay mineral assemblages are dominated by illite and smectite, with lesser abundance of chlorite and kaolinite. 87 Sr / 86 Sr and (0) isotopic data, combined with the smectite Nd / (illite + chlorite) ratio, indicate that the Pearl River is the main contributor for detrital material to the northern margin of the SCS, with variable continental input of volcanic material derived from the erosion of the Luzon Arc. These inputs follow the lowlatitude solar insolation with a 23 ky periodicity, as recorded by a periodic change of the clay mineralogy. For the first time, this study presents a SCS deep-sea sediment high-resolution record of climatic changes in the last 450 ky, showing that smectite / (illite + chlorite) variations are mainly related to changes in the East Asian summer monsoon intensity. Because the mineralogical record is independent of other external forcing phenomena such as global glacial/interglacial oscillations, the smectite / (illite + chlorite) ratio has been used here as a proxy to reconstruct past changes of the South-East Asian summer monsoon intensity. © 2005 Elsevier B.V. All rights reserved. 1503 Did tree-Betula, Pinus and Picea survive the last glaciation along the west coast of Norway? A review of the evidence, in light of Kullman (2002) Birks H.H., Larsen E. and Birks H.J.B. Journal of Biogeography 2005 32/8 (1461-1471) Aim: We discuss the hypotheses proposed by Kullman [Geo¨ Oko 21 (2000) 141; Nordic Journal of Botany 21 (2001) 39; Journal of Biogeography 29 (2002) 1117] on the basis of radiocarbon-dated megafossils of late-glacial age from the central Swedish mountains that boreal trees survived the glaciation along the south-west coast of Norway and subsequently migrated eastward early in the late-glacial to early deglaciated parts of the central Swedish Scandes mountains. Methods: We assess these hypotheses on the basis of glacial geological evidence and four lines of palaeoecological evidence, namely macro fossil records of the tree species, vegetation and climate reconstructions from plant evidence, independent climate reconstructions from other proxies for the late-glacial environment of south-west Norway, and the patterns of post-glacial spread of the tree species. Location: South and west Norway, central Swedish Scandes mountains (J¨amtland). Results and conclusions: South-west Norway and the adjacent continental shelf were under ice at the last-glacial maximum (LGM). The late-glacial vegetation of south-west THE QUATERNARY Norway was treeless and summer temperatures were below the thermal limits for Betula pubescens Ehrh., Pinus sylvestris L. and Picea abies (L.) Karst. Instead of spreading immediately after the onset of Holocene warming, as might have been expected if local populations were surviving, B. pubescens showed a lag of local arrival of 600 to > 1000 years, Pinus lagged by 1500 to > 2000 years, and Picea only reached southern Norway c. 1500 years ago and has not colonized most of south-west Norway west of the watershed. Glacial geological evidence shows the presence of an ice sheet in the Scandes at the LGM and in the Younger Dryas, which was cold-based near or at the area where the late-glacial-dated megafossils were recovered by Kullman. We conclude that the samples dated by Kullman (2002) should be evaluated carefully for possible sources of contamination. All the available evidence shows that the biogeographical hypotheses, based on these radiocarbon dates taken at face value, of late-glacial tree survival at the Norwegian coast and subsequent eastwards spread to the mountains, are unsupportable. © 2005 Blackwell Publishing Ltd. 1504 Temperatures of the habitat of quaternary mollusks from Azerbaijan as determined from the Ca/Mg ratio Aliyev S.A. and Sari A. Geochemistry International 2005 43/9 (920-927) This study focuses on the characterization of calcium and magnesium distribution in the shells of Quaternary mollusks from Azerbaijan and paleotemperature estimates from the Ca/Mg ratio. Using the obtained paleotemperature values, three stages of temperature maximum were distinguished in the Quaternary period: Holocene (19.9-24.3°C), early Khvalyn (19.6-24.4°C), and early Khazar (19.3-22.2°C); and two stages of cooling: late Khvalyn (13.5-15.7°C) and late Khazar (15.9-17.2°C), corresponding to the glacial and interglacial epochs of the late Pleistocene. The obtained temperatures of the marine habitat and sedimentation in the Caspian Sea (from the Ca/Mg ratio) were compared with temperature data for the eastern Mediterranean Sea determined by various methods. The reported calcium-magnesium paleotemperatures are in agreement with the paleotemperature estimates obtained by the investigation of the species composition of various systematic groups of planktonic foraminifera and 18 O in the Late Quaternary basins of the eastern Mediterranean Sea (including the Sea of Marmara). These data provide an adequate record of variations in the temperature conditions of the habitat of Caspian mollusks of Azerbaijan in Quaternary time. Copyright © 2005 by MAIK "Nauka/ Interperiodica" (Russia). 1505 Lateglacial palaeoenvironments and palaeoclimates from Conty and Houdancourt, northern France, reconstructed from Beetle remains Ponel P., Coope R., Antoine P. et al. Quaternary Science Reviews 2005 24/23-24 (2449-2465) Two Lateglacial insect sequences are described (a) from Conty, in the Selle valley and (b) from Houdancourt in the Oise valley, both in northern France. These investigations are part of a multidisciplinary investigation involving archaeology, sedimentology, geomorphology, geochronology and palaeontology (pollen, macroscopic plant remains, vertebrates, molluscs and insect fossils). The sequences of insect assemblages date from the latter part of the Bølling to the end of the Allerød periods. Environmental analysis of these faunas shows that rivers with riffles and pools meandered across flood plains. The river was extensively fringed with reedy vegetation. The only trees growing close to the river were of Salix and/or Populus. All the insect assemblages indicate that the thermal climates during the Bølling and Allerød periods were similar to one another and during both periods were very nearly as warm as that of the present day. No insect fossils were recovered from the sediments attributed to the Older Dryas interval though other evidence from these sites suggests that this event was decidedly colder than those immediately preceding and succeeding it. Comparisons are made between Lateglacial climatic patterns in northern France with those elsewhere in Europe. © 2005 Elsevier Ltd. All rights reserved. 285 1506 A review of Late Pleistocene and Holocene biogeography of highland Mediterranean pines (Pinus type sylvestris) in Portugal, based on wood charcoal Figueiral I. and Carcaillet C. Quaternary Science Reviews 2005 24/23-24 (2466-2476) The historical biogeography of highland Mediterranean pines is explored based on Late Pleistocene and Holocene charcoal from Portugal (Iberian Peninsula, SW Europe). The earliest presence of Pinus type sylvestris (including P. nigra, P. sylvestris and P. uncinata) is recorded in archaeological layers dated at ca 23,900 BP, during the Full Glacial. The abundance of remains identified as Pinus type sylvestris suggests that this was a frequent taxon, at least at middle altitudes. Significant occurrences were recorded up until ca 11,000 BP, at the end of the Lateglacial warming period. From the early Holocene onwards the presence of Pinus type sylvestris is recorded only sporadically, but at least up to 2000 years ago. The competition with other tree and shrub species favoured by the Holocene warming may have triggered the decline of highland pines in Portugal. Eventual anthropogenic impact is also considered as playing a role in its regional decline, such as increasing fire frequency resulting from amplified land use since the Neolithic. © 2005 Elsevier Ltd. All rights reserved. 1507 Shallow-marine sediment cores record climate variability and earthquake activity off Lisbon (Portugal) for the last 2000 years Abrantes F., Lebreiro S., Rodrigues T. et al. Quaternary Science Reviews 2005 24/23-24 (2477-2494) Sea Surface Temperature (SST), river discharge and biological productivity have been reconstructed from a multi-proxy study of a high-temporal-resolution sedimentary sequence recovered from the Tagus deposition center off Lisbon (Portugal) for the last 2000 years. SST shows 2°C variability on a century scale that allows the identification of the Medieval Warm Period (MWP) and the Little Ice Age (LIA). High Iron (Fe) and fine-sediment deposition accompanied by high n-alkane concentrations and presence of freshwater diatoms during the LIA (1300-1900 AD) (Science 292 (2001) 662) suggest augmented river discharge, whereas higher total-alkenone concentrations point to increased river-induced productivity. During the MWP (550-1300 AD) (Science 292 (2001) 662) larger mean-grain size and low values of magnetic susceptibility, and concentrations of Fe, n-alkanes, and n-alcohols are interpreted to reflect decreased runoff. At the same time, increased benthic and planktonic foraminifera abundances and presence of upwelling related diatoms point to increased oceanic productivity. On the basis of the excellent match found between the negative phases of the North Atlantic Oscillation (NAO) index and the intensified Tagus River discharge observed for the last century, it is hypothesized that the increased influx of terrigenous material during the LIA reflects a negative NAO-like state or the occurrence of frequent extreme NAO minima. During the milder few centuries of the MWP, stronger coastal upwelling conditions are attributed to a persistent, positive NAO-like state or the frequent occurrence of extreme NAO maxima. The peak in magnetic susceptibility, centered at 90 cm composite core depth (ccd), is interpreted as the result of the well-known 1755 AD Lisbon earthquake. The Lisbon earthquake and accompanying tsunami are estimated to have caused the loss of 39 cm of sediment (355 years of record - most of the LIA) and the instantaneous deposition of a 19-cm sediment bed. © 2004 Elsevier Ltd. All rights reserved. 1508 Moving front or population expansion: How did Picea abies (L.) Karst. become frequent in central Sweden? Giesecke T. Quaternary Science Reviews 2005 24/23-24 (24952509) The Holocene increase in Picea abies around four central Swedish lakes was analysed using extended pollen counts over the sections comprising the tail of frequent, but discontinuous, occurrences and the beginning of the continuous curve. Simple landscape scenarios were simulated to test possible mechanisms of the spread and population expansion of P. abies in Scandinavia. Predicted patterns of pollen accumulation rates from the landscape scenarios were compared to patterns observed at the four sites to explore how the observed curves could have come about. Simulations of a moving front scenario indicate that pollen accumulation 286 THE QUATERNARY rates should rise faster than the exponential and logistic increase observed at the four sites. Exponential increase of pollen values at the sites is most likely due to locally increasing populations. However, the geography of expanding populations may influence the shape of the curve. Empirical and model results are discussed to gain new insights into the pattern and processes of the spread of P abies in central Sweden. Propagule pressure and self-fertilisation are considered as possible explanations of why small outpost populations that may have existed before the regional expansion of P. abies did not expand earlier. © 2005 Elsevier Ltd. All rights reserved. 1509 The dynamics of chironomid assemblages and vegetation during the Late Quaternary at Laguna Facil, Chonos Archipelago, southern Chile Massaferro J., Brooks S.J. and Haberle S.G. Quaternary Science Reviews 2005 24/23-24 (2510-2522) We compare high-resolution pollen and chironomid records from the last 15,000 yr in Laguna Facil, southern Chile. Major vegetation and chironomid changes are recorded between ca 14,900 and 14,700 cal. yr BP. During the Lateglacial, changes in the chironomid stratigraphy lag behind changes in the pollen stratigraphy suggesting that the chironomids are responding to changes in the tree canopy or in soil chemistry brought about by vegetational development. At about 7200 cal. yr BP there is a change in the chironomid stratigraphy in advance of changes in the vegetation. This suggests that the response is to regional climatic change. The relatively close correlation of the chironomid and pollen stratigraphies with changes in charcoal concentrations also implicates the importance of fire and/or vulcanism in influencing the dynamics of forest and limnological systems. There is no clear evidence of cooling during the Younger Dryas chronozone in Laguna Facil. © 2005 Elsevier Ltd. All rights reserved. 1510 Synchrony of Southern Hemisphere Late Pleistocene arid episodes: A review of luminescence chronologies from arid aeolian landscapes south of the Equator Munyikwa K. Quaternary Science Reviews 2005 24/23-24 (25552583) Luminescence-dating chronologies that have been reported in various studies of Late Pleistocene arid-land aeolian sequences from Australia, southern Africa and South America are reviewed with the objective of determining whether any pan-hemispheric synchroneity existed in the timing of landscape responses to Late Quaternary climate changes south of the equator. The results broadly show that contemporaneous regional arid-land aeolian activity occurred in Australia and southern Africa during the periods ca 65-41 and 36-9 ka. The relatively limited luminescence data from the South American subcontinent also point to recurrent arid-land aeolian deposition between 63 and 8 ka, with increasing frequency in the period ca 32-8 ka. Records from all three continents suggest a period of reduced aeolian activity between 41 and 36 ka. Overall, the data are indicative of extensive landscape instability of the low to mid-latitudes in the Southern Hemisphere during the last glacial period, particularly at the Last Glacial Maximum, which accords with mainstream opinions. Aeolian activity during the Holocene has generally been localised. The rigour with which comparisons can be made between the different studies, however, is constrained by variations in practices between laboratories and changes that have occurred to luminescence dating procedures over the years. © 2005 Elsevier Ltd. All rights reserved. 1511 Climatic and environmental changes at southeastern coast of Lake Biwa over past 3000 years, inferred from borehole temperature data Goto S., Hamamoto H. and Yamano M. Physics of the Earth and Planetary Interiors 2005 152/4 (314-325) In order to infer past climatic change in central Japan, we measured temperatures in a borehole at the Karasuma site, on the southeastern coast of Lake Biwa, and reconstructed sediment surface temperature history during the last 3000 years. The reconstructed temperature history shows apparent Medieval Warm Period, Little Ice Age, and contemporary temperature warming. However, the large amplitude of the temperature changes up to 4-5 K cannot be explained by past climatic change only, sug- gesting that there was some other cause of the larger amplitude temperature changes. The onsets of temperature decrease in the late 12th century A. D. and temperature increase in the mid 17th century A. D. appear to coincide with occurrences of two destructive earthquakes (1185 and 1662 A. D.) that caused water level changes of Lake Biwa. It suggests that the reconstructed sediment surface temperature history reflects the environmental change due to tectonically induced water level changes of the lake. If the annual mean of the ground surface temperature was higher than that of the bottom water temperature in a shallow part of the lake, which is consistent with the present-day data, the large amplitude of the sediment surface temperature change may be attributed to a combined effect of past climatic and environmental changes. Thus, we suggest that the borehole temperature at the Karasuma site preserves information not only on past climate changes but also on environmental changes due to tectonically induced water level changes. © 2005 Elsevier B.V. All rights reserved. 1512 Isotopic and biogeochemical markers help in reconstructing the Lazaret Cave environment (Nice, France) during upper Pleistocene (IOS-5) (French) (Apport des marqueurs isotopiques et biog´eochimiques dans la reconstitution du pal´eoenvironnement de la grotte du Lazaret (Nice, Alpes-Maritimes) au cours du Pl´eistoc`ene sup´erieur (stade isotopique 5)) Rousseau L., Beauchamp J., Falgu`eres C. et al. Comptes Rendus - Geoscience 2005 337/15 (1348-1354) The isotopic composition of calcite from the stalagmitic floor E of the Lazaret Cave is interpreted as proxy of atmospheric circulation and vegetal cover changes during IOS 5. The 18O variations could indicate change in precipitation sources, which could originate from the Mediterranean Sea during warm periods and from the Atlantic Ocean during colder periods. The 13C variations could be related to vegetal cover and soil type. Tree cover appears to be dominant according to pollen spectra, and organic molecules trapped into calcite (sterols, terpenoids, humic acids). © 2005 Acad´emie des sciences. Publi´e par Elsevier SAS. Tous droits r´eserv´es. 1513 Aeolian process and pedogenesis under the influence of the East Asian monsoon: A statistical approach to particlesize distribution variability Parker E.J. and Bloemendal J. Sedimentary Geology 2005 181/34 (195-206) The grain size of Chinese loess has been widely regarded as a sensitive proxy for the intensity of the wind strength associated with the winter component of the East Asian monsoon. The majority of papers concerned with loess particle size examine variations in moments of the particle size distribution. However, in coastal geomorphological research parametric models have been used and the samples represented by resulting parameter estimates. Here we investigate the use of log-hyperbolic and log-skew-laplace models to distinguish between loess, loess subgroups and palaeosols in a particularly high accumulation rate profile from the NW Chinese loess plateau area. The aim is to define narrow units of ‘pristine’ loess that may indicate brief returns to dust storm conditions. With this approach, units within the loess, previously ascribed to Heinrich events, can be seen to have a particular particle size distribution signature, thus allowing them to be stratigraphically and environmentally constrained. Parametric models applied to grain-size distribution data in Chinese loess make a useful addition to previously used particle size techniques that have demonstrated cyclicity on a scale similar to that of Dansgaard-Oeschger events in ice cores and those designed to determine the degree of loess pedogenesis such as micromorphology and magnetic enhancement. The aim of our work is to make full use of particle size distribution data in the wider context of palaeoenvironmental reconstruction. © 2005 Elsevier B.V. All rights reserved. 1514 An ostracode based paleolimnologic and paleohydrologic history of Death Valley: 200 to 0 ka Forester R.M., Lowenstein T.K. and Spencer R.J. Bulletin of the Geological Society of America 2005 117/11-12 (1379-1386) Death Valley, a complex tectonic and hydrologic basin, was cored from its lowest surface elevation to a depth of 186 m. The sediments range from bedded primary halite to black muds. Con- THE QUATERNARY tinental ostracodes found in the black muds indicate that those sediments were deposited in a variety of hydrologic settings ranging from deep, relatively fresh water to shallow saline lakes to spring discharge supported wetlands. The alkaline-enriched, calcium-depleted paleolake waters indicate extrabasinal streamflow and basin-margin spring discharge. The alkaline-depleted, calcium-enriched paleowetland waters indicate intrabasinal spring discharge. During Marine Isotope Stage 6 (MIS 6, ca. 180-140 ka) the hydrologic settings were highly variable, implying that complex relations existed between climate and basin hydrology. Termination II (MIS 6 to MIS 5E) was a complex multicyclic sequence of paleoenvironments, implying that climates oscillated between high and low effective moisture. MIS 4 (ca. 73-61 ka) was a spring discharge supported wetland complex. During MIS 2 (ca. 20-12 ka) the hydrologic settings were variable, although they are not fully understood because some black muds deposited during that time were lost during coring. © 2005 Geological Society of America. 1515 Temperature variations recovered from tree-rings in the middle Qilian Mountain over the last millennium Liu X., Qin D., Shao X. et al. Science in China, Series D: Earth Sciences 2005 48/4 (521-529) Based on the cross-dated tree-ring samples collected from the middle Qilian Mountain, a standard ring-width chronology had been developed, which covered the period AD 1000 to 2000. The correlations between the chronology and climatic records from the nearby meteorological stations indicated that temperature was the dominant climatic factor for tree growth at upper timberline, and the most important climatic factor for the tree growth in the area was the mean temperature from previous December to current April. The temperature variations recovered from the ring-width data showed a cold period during the "Little Ice Age" and the continuous warming during the twentieth century. Comparison between the ring-width chronology and 18 O records from the Dunde ice core in the Qilian Mountain indicated that there was a consistent trend in both time series. A significant correlation existed between our ring-width chronology and the Northern Hemispheric temperature, suggesting that the climate changes in the Qilian Mountain were not only driven by regional factors, but also responsive to the global climate. Copyright by Science in China Press 2005. 1516 The Y. D. and climate abrupt events in the early and middle Holocene: Stalagmite oxygen isotope record from Maolan, Guizhou, China Qin J., Yuan D., Cheng H. et al. Science in China, Series D: Earth Sciences 2005 48/4 (530-537) The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 45 cm to 193.6 cm of the upper part of D4 stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope analyses. The study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4 record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in temperature reaching 2 - 5°C. The climate abrupt events in thousand and hundred years scale recorded in stalagmite 18 O can be compared to those in GISP2 ice cores from Greenland in their happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in China monsoon areas, western Europe and polar regions, have the same driving factor. This has a global significance. In addition, the trend of record curves in some time-stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions. Copyright by Science in China Press 2005. 287 1517 Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records Yan Y., Kang S., Sun J. et al. Science in China, Series D: Earth Sciences 2005 48/4 (576-584) Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+ ) concentration and SLP series show that ssNa + concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Subtropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa + records from the Mt. Logan region can be considered as a proxy for reconstructing the autumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low. Copyright by Science in China Press 2005. 1518 Lake sediment records on climate change and human activities since the Holocene in Erhai catchment, Yunnan Province, China Shen J., Yang L., Yang X. et al. Science in China, Series D: Earth Sciences 2005 48/3 (353-363) According to high-resolution analyses on multi-proxy of sediment core from the Erhai Lake, Yunnan Province, the sequence of climatic and environmental change since the Holocene has been reconstructed based on accurate dating. The results show that climate had transited from cold-wet to warm-wet during ca. 12950-8399 aBP in this area, and the transition happened in ca. 10329 aBP. Due to the enhancing southwest Asian monsoon and increasing precipitation, the lake-level of the Erhai Lake began to rise after ca. 10329 a BP. Climate in the catchment was warm and wet during the mid-Holocene, and the warmest stage appeared in ca. 8399-6371 a BP. The lake-level descended in the mid-Holocene because of the decrease of effective moisture in the basin. Human activities appeared in ca. 6371 a BP, and the initial manner mainly focused on deforestation. Up to ca. 2139 a BP, due to the amount of immigration into this area, the cultivation was developed widely, which was followed by mining (coal mine). Copyright by Science in China Press 2005. 1519 Lithology and stratigraphy of sediment cores from the Eifel dry maar lakes (German) (Lithologie und Stratigraphie der sp¨atpleistoz¨anen Trockenmaare der Eifel) Schaber K. and Sirocko F. Mainzer Geowissenschaftliche Mitteilungen 2005 -/33 (295-340) Twentytwo long sediment cores from 12 Eifel dry maar lakes and one modern lake are stratigraphically correlated to obtain a continuous record of the history of sedimentation during the last climatic cycle from today back to 140 000 years ago. The backbone of the stratigraphy is based on 64 AMS 14 C dates, 4 luminescence dates and the occurrence of the 5 to 20 cm thick deposits of the phonolithic D¨umpelmaar tephra, which is found in all records immediately above the annually laminated sections of the last interglacial. Greyscale variations in the sections of the last glacial show a stadial/ interstadial succession, which is highly similar to the Greenland ice core NorthGRIP, which allows high precision tuning of the stratigraphy, and document also the tight link between the North Atlantic/Greenland climate and central Europe. The sediments of the 22 cores reveal 3 different lithotypes, wh ich are synthesized into a general lithological profile. Accordingly, the last interglacial sediments are always fine grained laminae which allow varve counting in a few cases. A short episode of strong seismic activity immediately after the last interglacial caused seismites in the center of the lakes and 288 THE QUATERNARY slumps around the flanks. Early Weichselian sediments are still organic rich, but with much more clastic input than during the interglacial. Massive slumps indicate a lake level regression during the beginning of the marine oxygen isotope stage 4, which is then dominated by eolian sediments. The early interstadials of MIS3 are again rich in organic carbon content, stadials reveal abundant loess, which becomes dominating during the last glacial maximum. The phonolithic tephra of the Laacher See eruption is the second distinct chronological marker immediately above a fast transition to high organic carbon contents at the begin of the Holocene. This succession of sedimentation is typical for all Eifel maar lakes and clearly reflects the climate evolution of the last glacial cycle. 1520 Phosphorus geochemistry in the Luochuan loess section, North China and its paleoclimatic implications Rao W., Chen J., Luo T. and Liu L. Quaternary International 2005 144/1 (72-83) Total P (Pt ) on a carbonate-free basis in an entire loess-paleosol sequence and Pt , organic P (Po ) and inorganic P (Pi ) in the S0 -L1 - S1 sequence were investigated in detail with different resolutions for the Luochuan loess section from northern China. Pt content varies between 393 and 786 ppm throughout the loesspaleosol sequence, and is generally higher in the loess than in interstratified paleosols, showing fluctuation cycles of 100 ka in correspondence to loess-paleosol alternations. Pt variations on a carbonate-free basis in the loess-paleosol sequence could indicate variations in atmosphere precipitation resulting in different leaching loss of P from paleosols. Pi has an average value of 499 ppm with a range of 324-560 ppm, accounting for more than 70% of Pt in the S0 -L1 -S1 sequence, where the minimum of Pi in the Malan loess is higher than the maximum of Pi in S1 . Po ranges between 59 and 233 ppm with an average of 132 ppm in the S0 - L1 -S1 sequence. Phosphorus (P) was initially delivered to the Luochuan loess section via influx of aeolian dust from the northern desert and Gobi areas by the East Asian winter monsoon, and then was modified by pedogenesis associated with the East Asian summer monsoon during the last 130 ka. "Preserved Pt " in the loess L1 is tightly correlated with grain size without leaching loss of P due to enrichment of P in fine-grained fractions, as well as "initial Pt ". "Leaching Pt " data show that paleosol S1 had lost 15-40% of its "initial Pt ", and that there was much more precipitation in S1 than in L1 . Pi subject to slightly weak pedogenesis was completely transformed into Po without leaching loss of P in loess L1 . By contrast, much Pi disappeared from paleosol S1 due to strong pedogenesis, partly through leaching and partly through conversion to organic forms during P cycling processes. Po variation is similar to those of MS and the <7.8 m fraction in L1 , but contains more information on the East Asian winter monsoon due to weak pedogenesis without leaching of P. Po in S1 lower than L1 SS1 as a consequence of strong decomposition of the organic matter kept constantly in the middle of S1 where Pi kept at the lowest of 423 ppm, suggesting that there existed a very warm and humid climate related to the enhanced summer monsoon during that period. The mean organic P/inorganic P ratio (Po /Pi ) is lower in the L1 LL1 and L1 LL2 than in the S0 , S1 and L1 SS1 , indicating that low Po /Pi ratios coincide with weak weathering-pedogenesis, and higher Po /Pi ratios correspond to strong weathering-pedogenesis. Po /Pi ratio can eliminate the effect of grain size on aeolian dust because of chemical uniformity of aeolian dust and enrichment of Po and Pi in the fine-grained fractions. Thus, Po / Pi ratio is solely linked to pedogenesis of the Luochuan loess section. Variation in Po /Pi ratio is similar to those of MS and the Marine Oxygen Isotope composition, indicating the summer monsoon evolution during the last 130 ka and providing the biogeochemical evidence for further understanding the genetic links between the East Asian monsoon and global climate change. © 2005 Elsevier Ltd and INQUA. All rights reserved. 1521 Modern pollen-rain characteristics of tall terra firme moist evergreen forest, southern Amazonia Gosling W.D., Mayle F.E., Tate N.J. and Killeen T.J. Quaternary Research 2005 64/3 (284-297) The paucity of modern pollen-rain data from Amazonia constitutes a significant barrier to understanding the Late Quaternary vegetation history of this globally important tropical forest re- gion. Here, we present the first modern pollen-rain data for tall terra firme moist evergreen Amazon forest, collected between 1999 and 2001 from artificial pollen traps within a 500 20 m permanent study plot (14°34 50 S, 60°49 48 W) in Noel Kempff Mercado National Park (NE Bolivia). Spearman’s rank correlations were performed to assess the extent of spatial and inter-annual variability in the pollen rain, whilst statistically distinctive taxa were identified using Principal Components Analysis (PCA). Comparisons with the floristic and basal area data of the plot (stems 10 cm d.b.h.) enabled the degree to which taxa are over/under-represented in the pollen rain to be assessed (using R-rel values). Moraceae/Urticaceae dominates the pollen rain (64% median abundance) and is also an important constituent of the vegetation, accounting for 16% of stems 10 cm d.b.h. and ca. 11% of the total basal area. Other important pollen taxa are Arecaceae (cf. Euterpe), Melastomataceae/Combretaceae, Cecropia, Didymopanax, Celtis, and Alchornea. However, 75% of stems and 67% of the total basal area of the plot 10 cm d.b.h. belong to species which are unidentified in the pollen rain, the most important of which are Phenakospermum guianensis (a banana-like herb) and the key canopy-emergent trees, Erisma uncinatum and Qualea paraensis. © 2005 University of Washington. All rights reserved. 1522 15,000-yr pollen record of vegetation change in the high altitude tropical Andes at Laguna Verde Alta, Venezuela Rull V., Abbott M.B., Polissar P.J. et al. Quaternary Research 2005 64/3 (308-317) Pollen analysis of sediments from a high-altitude (4215 m), Neotropical (9°N) Andean lake was conducted in order to reconstruct local and regional vegetation dynamics since deglaciation. Although deglaciation commenced 15,500 cal yr B.P., the area around the Laguna Verde Alta (LVA) remained a periglacial desert, practically unvegetated, until about 11,000 cal yr B.P. At this time, a lycopod assemblage bearing no modern analog colonized the superp´aramo. Although this community persisted until 6000 cal yr B.P., it began to decline somewhat earlier, in synchrony with cooling following the Holocene thermal maximum of the Northern Hemisphere. At this time, the pioneer assemblage was replaced by a low-diversity superp´aramo community that became established 9000 cal yr B.P. This replacement coincides with regional declines in temperature and/or available moisture. Modern, more diverse superp´aramo assemblages were not established until 4600 cal yr B.P., and were accompanied by a dramatic decline in Alnus, probably the result of factors associated with climate, humans, or both. Pollen influx from upper Andean forests is remarkably higher than expected during the Late Glacial and early to middle Holocene, especially between 14,000 and 12,600 cal yr B.P., when unparalleled high values are recorded. We propose that intensification of upslope orographic winds transported lower elevation forest pollen to the superp´aramo, causing the apparent increase in tree pollen at high altitude. The association between increased forest pollen and summer insolation at this time suggests a causal link; however, further work is needed to clarify this relationship. © 2005 University of Washington. All rights reserved. 1523 Paleoecological and climatic changes of the Upper Lerma Basin, Central Mexico during the Holocene Ludlow- Wiechers B., Almeida- Le˜nero L. and Islebe G. Quaternary Research 2005 64/3 (318-332) The record of Almoloya Lake in the Upper Lerma basin starts with the deposition of the late Pleistocene Upper Toluca Pumice layer. The data from this interval indicate a period of climatic instability that lasted until 8500 cal yr B.P., when temperature conditions stabilized, although moisture fluctuations continued until 8000 cal yr B.P. Between 8500 and 5000 cal yr B.P. a temperate climate is indicated by dominance of Pinus. From 5000 to 3000 cal yr B.P. Quercus forest expanded, suggesting a warm temperate climate: A first indication of drier environmental conditions is an increase in grassland between 4200 and 3500 cal yr B.P. During the Late Holocene (3300 to 500 cal yr B.P.) the increase of Pinus and grassland indicates temperate dry conditions, with a considerable increase of Pinus between 1100 and 950 cal yr B.P. At the end of this period, humidity increased. The main tendency during the Holocene was a change from humid THE QUATERNARY to dry conditions. During the Early Holocene, Almoloya Lake was larger and deeper; the changing humidity regime resulted in a fragmented marshland, with the presence of aquatic and subaquatic vegetation types. 1524 A 23,000-yr pollen record from Lake Euramoo, Wet Tropics of NE Queensland, Australia Haberle S.G. Quaternary Research 2005 64/3 (343-356) A new extended pollen and charcoal record is presented from Lake Euramoo, Wet Tropics World Heritage rainforest of northeast Queensland, Australia. The 8.4-m sediment core taken from the center of Lake Euramoo incorporates a complete record of vegetation change and fire history spanning the period from 23,000 cal yr B.P. to present. The pollen record is divided into five significant zones; 23,000-16,800 cal yr B.P., dry sclerophyll woodland; 16,800-8600 cal yr B.P., wet sclerophyll woodland with marginal rainforest in protected pockets; 8600-5000 cal yr B.P., warm temperate rainforest; 5000-70 cal yr B.P., dry subtropical rainforest; 70 cal yr B.P.-AD 1999, degraded dry subtropical rainforest with increasing influence of invasive species and fire. The process of rainforest development appears to be at least partly controlled by orbital forcing (precession), though more local environmental variables and human activity are also significant factors. This new record provides the opportunity to explore the relationship between fire, drought and rainforest dynamics in a significant World Heritage rainforest region. © 2005 University of Washington. All rights reserved. 1525 Paleoclimate changes during the last 100,000 yr from a record in the Brazilian Atlantic rainforest region and interhemispheric comparison Ledru M.- P., Rousseau D.- D., Cruz Jr. F.W. et al. Quaternary Research 2005 64/3 (444-450) A long terrestrial record, Colˆonia CO-3, from the Atlantic rainforest region in Brazil (23°52 S, 46°42 20 W, 900 m a.s.l.) registrates variations in the forest expansion during the last 100,000 yr. The 780-cm depth core was analyzed at 2-cm intervals and arboreal pollen frequencies were compared to nearby speleothem stable isotope records and neighboring marine records from the tropical Atlantic. To evaluate regional versus global climate forcing, our record was compared with Greenland and Antarctic ice-core records. These comparisons suggest that changes in temperature seen in polar latitudes relate to moisture changes: e.g., to changes in the length of the dry season, in tropical and subtropical latitudes during glacial as well as interglacial times. These climatic changes result from changes in the frequency of polar air incursions to these latitudes inducing a permanent cloud cover and precipitation. This is an important result that should help define paleoclimatic features in the Southern Hemisphere for the last glaciation. © 2005 University of Washington. All rights reserved. 1526 A Holocene pollen and diatom record from Vanderlin Island, Gulf of Carpentaria, lowland tropical Australia Prebble M., Sim R., Finn J. and Fink D. Quaternary Research 2005 64/3 (357-371) Sedimentary, palynological and diatom data from a dunefield lake deposit in the interior of Vanderlin Island in the Gulf of Carpentaria are presented. Prior to the formation of present perennial lake conditions, the intensified Australian monsoon associated with the early Holocene marine transgression allowed Cyperaceae sedges to colonise the alluvial margins of an expansive salt flat surrounded by an open Eucalyptus woodland. As sea level stabilised between 7500 and 4500 cal yr B.P. coastal dunes ceased to develop allowing dense Melaleuca forest to establish in a Restionaceae swamp. Dune-sand input into the swamp was diminished further as the increasingly dense vegetation prevented fluvial and aeolian transported sand arriving from coastal sources. This same process impounded the drainage basin allowing a perennial lake to form between 5500 and 4000 cal yr B.P. Myriophyllum and other aquatic taxa colonised the lake periphery under the most extensive woodland recorded for the Holocene. The palynological data support an effective precipitation model proposed for northern Australia that suggests more variable conditions in the late Holocene. A more precise measure of effective precipitation change is provided by diatom-based inferences that indicate few changes in lake hydrology. Such interpretations are 289 explained in terms of palynological sensitivity to adjustments in local fire regimes where regional precipitation change may only be recorded indirectly through fire promoting mechanisms, including intensified ENSO periodicity and human impact. © 2005 University of Washington. All rights reserved. 1527 High-resolution pollen record from core KW31, Gulf of Guinea, documents the history of the lowland forests of West Equatorial Africa since 40,000 yr ago Lezine A.- M. and Cazet J.- P. Quaternary Research 2005 64/3 (432-443) Pollen data from core KW31 recovered off the mouth of the Niger River (3°31 1N-05°34 1E; 1181 m water depth) provide an exceptional record of vegetation changes in the West African lowlands between 40,000 and 3500 cal yr B.P. The highly diverse microflora testify for the permanency of rain and secondary forests in the Niger river catchment, at least as gallery formations along rivers, during the last glacial period when dry conditions occurred in relation to enhanced trade-wind circulation. The direct consequence of the post-glacial warming and the correlative increase in monsoon fluxes over West Africa was the increase in forest diversity and the expansion of rain and secondary forests on the nearby continent. Comparison between KW31 pollen record and continental pollen data from 5°S to 25°N allows the evaluation of migration rates of tropical forest populations throughout North West Africa at the beginning of the Holocene and the vegetation response to the shift toward aridity recorded widely at the end of the African Humid Period around 4000 cal yr B.P. © 2005 University of Washington. All rights reserved. Oceans 1528 Analyses of a large-scale depositional clinoformal wedge along the Italian Adriatic coast Niedoroda A.Wm., Reed C.W., Das H. et al. Marine Geology 2005 222-223/1-4 (179-192) The processes controlling the formation of the late Holocene high-stand systems tract along the central Adriatic coast - a prograding clinoformal sediment wedge - have been diagnosed using a large-scale behavior-oriented numerical model. This model is based on time-averaged marine sediment dynamics, allowing it to represent processes acting over millennial time spans. River-derived sediment is redistributed by the combined action of littoral, shoreface and shelf processes. In this application the numerical model successfully simulates both the overall geometry of the deposits and the internal time-line stratigraphy. The simulation of this prograding clinoform with the numerical model clearly shows that the growth of these deposits depends on the combined effect of a strong and persistent coast-parallel advection and cross-shelf dispersion related to a large number of sediment re-entrainment events. This means that this clinoform is in the process of forming a new shelf surface with an offshore profile that is in adjustment with the present wave and current climate along with the relative stability of sea level over the past six millennia. © 2005 Elsevier B.V. All rights reserved. 1529 Delta progradation and sediment fluxes since the last glacial in the Thermaikos Gulf and the Sporades Basin, NW Aegean Sea, Greece Lykousis V., Karageorgis A.P. and Chronis G.Th. Marine Geology 2005 222-223/1-4 (381-397) Late Quaternary sedimentary cover in the Thermaikos Gulf consists of three seismic Units: (i) the uppermost Unit A that represents delta progradation during the last 6000 yr when the sea surface almost reached the present level (Highstand Systems Tract, HST); (ii) Unit B that includes relatively coarsegrained sediments deposited in a shallow, high-energy, estuarine environment during the post-glacial transgression (Transgressive Systems Tract, TST); and (iii) the lowest Unit C which may represent late glacial prodeltaic deposits and slope to basin turbidites (Lowstand Systems Tract, LST). Seismic units A and B overlay a well-defined unconformity which resulted from subaerial erosion during the late glacial sea-level fall. Subtracting 290 THE QUATERNARY the thickness of Unit A from the present bathymetry, the paleorelief of the Late Holocene times (ca. 6000 yr BP, sea level up to - 20 m) was assessed. Similarly, the paleo-relief 24 000 yr BP (sea level - 100 to - 120 m) was estimated. The main morphological feature is the incised valley of a major river that resulted from the confluence of the Axios, Aliakmon, Loudias, Gallikos and possibly Pinios Rivers. Sediment fluxes in the NW Aegean Sea were estimated for three time spans of the Late Quaternary (Interval I: 6000 yr BP-present, Interval II: 18 000- 6000 yr BP and Interval III: 24 000-18 000 yr BP). The terrestrial sediment load supplied by the Axios, Aliakmon, Pinios, and smaller rivers, was estimated at 35.4 109 t for Interval I. 93% of this material was deposited on the continental shelf, whereas the remaining 7% was transported to the adjacent basin. The mean annual terrestrial flux was estimated at 5.5 106 t yr-1 . During Interval II, more than 79 109 t of terrestrial sediment were discharged into the area (terrestrial flux 6.6 106 t yr-1 ), of which 86% was deposited on the shelf. During Interval III, the terrestrial load was 40.6 109 t (terrestrial flux 6.8 106 t yr -1 ), and sediments were predominantly deposited on the slope and basin. Based on the sediment’s carbonate content, the biogenic loads and fluxes were also determined. The biogenic flux during Intervals II and III was found to be 2.5-times higher than during Interval I. © 2005 Elsevier B.V. All rights reserved. 1530 Isotopic and elemental records in a non-tropical coral (Cladocora caespitosa): Discovery of a new high-resolution climate archive for the Mediterranean Sea Silenzi S., Bard E., Montagna P. and Antonioli F. Global and Planetary Change 2005 49/1-2 (94-120) A 95-year annual record of skeletal Sr / Ca, Mg / Ca, 18 O and 13 C is reported for a non-tropical, slow-growing coral (Cladocora caespitosa) collected in the north-western Mediterranean Sea. Significant correlations were found for Sr / Ca vs. Mg / Ca, Sr / Ca vs. 18 O and for 18 O vs. 13 C, indicating the possibility of using this non-tropical species as a climatic and paleoclimatic biomarker. The Sr / Ca and Mg / Ca ratios as well as the 18 O composition in corals were compared against the Sea Surface Temperature (SST) data of IGOSS (Integrated Global Ocean Service System Products) for the north-western Mediterranean region. The Sr / Ca ratios show a significant correlation with the SST, according to the following equation: Sr / Ca (mmol/mol) = 11.25 ( 0.38) - 0.079 ( 0.026) SST (°C). The 18 O data do not appear to fit with the SST interval used, since the regression obtained is non-significant. This implies that other factors apart from temperature, such as the 18 O seawater , are affecting the coral 18 O. The relationship between Mg / Ca ratio and SST is not statistically significant. This is probably due to the heterogeneities in magnesium content found among the coral microstructures (calcification centres, surrounding fibres and dissepiments), along with other factors, such as the presence of microborings and/or organic matter. The annual record indicates a history of SST variation that is consistent with the instrumental measurements, and strongly suggests the feasibility of using this non-tropical coral as a new proxy for the Mediterranean Sea. © 2005 Elsevier B.V. All rights reserved. 1531 Late Quaternary sea-level highstands in the central and eastern Indian Ocean: A review Woodroffe C.D. Global and Planetary Change 2005 49/1-2 (121138) The relative sea-level history of several atolls in the central and eastern Indian Ocean, including the Cocos (Keeling) Islands, Chagos Archipelago, and the Maldives-Laccadive Archipelagoes, has been debated for over a century but takes on a particular significance in the face of anticipated climate change. For each of these central and eastern Indian Ocean atolls Pleistocene limestone is encountered at depths of 6-20 m below sea level. On the Cocos (Keeling) Islands this has been dated to Last Interglacial age. Conglomerate platform underlies the reef islands on Cocos within which a sequence of fossil microatolls of massive and branching Porites records a gradual fall of sea level relative to the atoll. In the Maldives, the significance of outcrops of ‘reef rock’ has been vigorously debated without resolving sea-level history. Although in situ Heliopora occurs on the reef flat of Addu Atoll, dated at around 2700 radiocarbon yrs BP, other evidence for higher sea level remains poorly constrained. Conglomerates of a similar age have been described from the Chagos Archipelago, but it has not been unequivocally demonstrated that they formed under conditions of relatively higher sea level. In contrast to reefs further west in the Indian Ocean, each of these atolls has living microatolls of massive Porites that have been constrained in their upward growth by sea level. Interpretation of the upper surface of two such specimens from the Cocos (Keeling) Islands indicates broad fluctuations in the sea surface over the past century; similar microatolls are described from the Maldives implying little change in sea level over recent years. Regardless of minor past fluctuations, most reef islands in the Maldives are particularly low-lying and appear vulnerable to inundation, and extracting a more detailed sea-level history remains an important challenge. © 2005 Elsevier B.V. All rights reserved. 1532 Palaeoceanography of the Banda Sea, and Late Pleistocene initiation of the Northwest Monsoon Spooner M.I., Barrows T.T., De Deckker P. and Paterne M. Global and Planetary Change 2005 49/1-2 (28-46) This paper details the Late Quaternary palaeoceanography of the Banda Sea based on analysis of core SHI 9016, located east of Timor. This core is located below the pathway of the Indonesian Throughflow, at a depth of 1805 m bsl. Planktonic foraminifera assemblages, the 18 O and 13 C of the foraminifer Globigerinoides ruber, and the total carbonate content of each sample were used to reconstruct the vertical structure of the water column through the past 80,000 yr. Today, the core site is characterised by high sea-surface temperature and high precipitation, which results in the formation of a low-salinity boundary layer. Sea-surface temperature estimates down core indicate minimal cooling during the last glacial maximum. Mean sea-surface temperatures ranged between 29.8°C and 26.6°C for the past 80,000 yr; sea-surface seasonality never increased above 3°C. In addition, the abundance of the planktonic foraminifera Neogloboquadrina dutertrei, Neogloboquadrina pachyderma, and Globigerinoides quadrilobatus indicates that the mixed layer (the low-salinity boundary layer of the Throughflow) thinned during Marine Isotope Stages 3 and 2. This enhanced a deep chlorophyll maximum (DCM) layer. The Northwest Monsoon was less intense for about 60,000 yr and then ‘switched on’ at 15,000 cal yr BP. This thickened the mixed layer, reducing the DCM, and increased SST seasonality in the Banda Sea. © 2005 Elsevier B.V. All rights reserved. 1533 Inherent correlation between decreased marine sedimentary phosphorus and glacial atmospheric CO2 decline Weng H.- X., Qin Y.- C. and Weng J.- K. Geophysical Research Letters 2005 32/18 (1-4) The environmental and biogeochemical information implicated by a sediment column from the northern shelf of the South China Sea suggests that the vertical phosphorus variation in the sediment column bares a negative correlation with those of calcium carbonate and cadmium. The functional correlation between CO2 and PO34 in seawater is given by calculating a series of chemical equilibriums, indicating a coupling relationship between the accumulation of marine sedimentary P and the atmospheric CO2 change. The decreased P accumulation in marine sediments correlated to the increase of marine primary production during the glacial period might act as a key factor causing glacial atmospheric CO2 decline. Copyright 2005 by the American Geophysical Union. 1534 Changes in the source and transport mechanism of terrigenous input to the Indian sector of Southern Ocean during the late Quaternary and its palaeoceanographic implications Thamban M., Naik S.S., Mohan R. et al. Proceedings of the Indian Academy of Sciences, Earth and Planetary Sciences 2005 114/5 (443-452) Changes in the terrigenous sediment source and transport mechanisms during the late Quaternary have been investigated using four sediment cores within the Indian sector of Southern Ocean, using the magnetic susceptibility (MS) and sedimentological records. Sediments deposited during the Holocene and other interglacial periods were characterised by low MS, low sand content, reduced ice-rafted detritus (IRD) input and increased THE QUATERNARY illite possibly transported via hydrographic advection from the south. The glacial intervals are characterised by high MS, high sand content, increased IRD input and reduced illite clays, derived from both local as well as Antarctic sources. Significant reduction in clay fraction and illite content during glacials suggests that the erosive and transporting capabilities of the deep and bottom waters could have reduced compared to the interglacial times. The changes in terrigenous influx to this region were significantly influenced by the rhythmic glacial-interglacial fluctuations in bottom circulation and the position of the Polar Front. © Printed in India. 1535 Palaeoceanographic implications of abundance and mean proloculus diameter of benthic foraminiferal species Epistominella exigua in sub-surface sediments from distal Bay of Bengal fan Saraswat R., Nigam R. and Barreto L. Proceedings of the Indian Academy of Sciences, Earth and Planetary Sciences 2005 114/5 (453-458) Temporal variation in abundance and mean proloculus diameter of the benthic foraminiferal species Epistominella exigua has been reconstructed over the last 50,000 yr BP, from a core collected from the distal Bay of Bengal fan, to assess its potential application in palaeoceanographic reconstruction studies. The down-core variation shows significant change in abundance of E. exigua during the last 50,000 yr BP. In view of the present day abundance of this species from areas with strong seasonal organic matter supply, we conclude that at 7, 22, 33 and 46 kyr BP, strong seasonality prevailed in the distal Bay of Bengal fan, probably indicating either strong or prolonged north-east monsoon or weakened south-west monsoon. For the first time, a strong correlation is observed in abundance and mean proloculus diameter of E. exigua. Based on coherent variation in mean proloculus diameter and abundance, it is postulated that mean proloculus diameter can also be used to infer increased seasonality in organic matter production, thus variation in strength or duration of monsoon. Thus, this study establishes that the downcore vaxiation in the abundance and mean proloculus diameter of Epistominella exigua can be used to infer past climatic variations from the distal Bay of Bengal fan. © Printed in India. 1536 Stable isotopes and sclerochronology of the bivalve Mesodesma donacium: Potential application to Peruvian paleoceanographic reconstructions Carr´e M., Bentaleb I., Blamart D. et al. Palaeogeography, Palaeoclimatology, Palaeoecology 2005 228/1-2 (4-25) Reconstructing the past ENSO (El Ni˜no Southern Oscillation) interannual variability requires very high resolution sea surface temperature (SST) proxies. In order to compensate for the lack of coral archive in the Eastern Pacific cold tongue, we studied the potentiality of the bivalve species Mesodesma donacium as a SST tracer for the Peruvian coast. Biomineralisation cycles and growth line formation in the shells are shown to be controlled by tides. The sclerochronology based on fortnightly cycles allowed us to compare local SST data with high resolution shell records. As a result of the high correlation between SST and aragonite 18 O, we calculated a linear SST-fractionation relationship for the 14-20°C range: T(°C)=(17.41 1.15)(3.66 0.16)( 18 Oarag./PDB - 18 Owat./SMOW ). The difference from the commonly used Grossman and Ku (1986) [Grossman, E.L., Ku, T.L., 1986. Oxygen and carbon fractionation in biogenic aragonite: temperature effect. Chemical Geology 59, 59-74] equation suggests the potential existence of a species dependence of vital effect within bivalves. This preliminary equation allows monthly-scale SST reconstructions with a 1.5°C precision using M. donacium archaeological shells from southern Peru, giving potential insights into the problem of past ENSO behaviour. © 2005 Elsevier B.V. All rights reserved. 1537 Orbitally paced paleoproductivity variations in the Timor Sea and Indonesian throughflow variability during the last 460 kyr Holbourn A., Kuhnt W., Kawamura H. et al. Paleoceanography 2005 20/3 (1-18) A high-resolution (1-2 kyr) multiproxy record from the Timor Sea in the easternmost Indian Ocean (International Marine Global Change (IMAGES) Program Core MD01-2378, latitude 291 13°04.95 S, longitude 121°47.27 E, 1783 in water depth) closely tracks changes in intermediate water ventilation and paleoproductivity over the last 460 kyr within one of the main outflow passages of the Indonesian Throughflow. Spectral analysis of five different flux-based productivity proxies indicates spectral power concentrated in the 100 kyr (glacial-interglacial) and the 23 kyr and 19 kyr (precessional) periods. Paleoproductivity maxima lead ice volume (benthic 18 O) maxima by 20° to 40° (1300 to 2600 years) at the precession band. The spectral differences in tropical paleoproductivity records from the Pacific and Indian oceans suggest that local processes (wind and circulation patterns driven by insolation) are dominant in driving productivity rather than large-scale tropical features. In the Timor Sea, productivity fluctuations over the last 460 kyr were strongly influenced by monsoonal wind patterns offshore NW Australia (23 and 19 kyr) and were also modulated by sea level-related variations in the intensity of the Indonesian Throughflow (100 kyr). Copyright 2005 by the American Geophysical Union. 1538 Diatom-bound 15 N/14 N: New support for enhanced nutrient consumption in the ice age subantarctic Robinson R.S., Sigman D.M., DiFiore P.J. et al. Paleoceanography 2005 20/3 (1-14) Diatom-bound 15 N/14 N was used to reconstruct the glacial nutrient status of the Subantarctic Zone in the Southern Ocean. Down-core records from both the Pacific and Indian sectors show 15 N of 5 to 6%‰ during the Last Glacial Maximum and a decrease, coincident with the glacial termination, to values as low as 2‰. The effect of either diatom assemblage or physiological change on the diatom-bound 15 N/14 N is unknown and cannot yet be ruled out as a possible explanation for the observed change. However, the consistency between Indian and Pacific sector records and with other paleoceanographic data suggests that the glacial-interglacial difference in diatom-bound 15 N/14 N was driven by higher consumption of nitrate in the subantarctic surface during the last ice age. Such a change in nutrient consumption may have resulted from atmospheric iron fertilization and/or decreased glacial mixed layer depths associated with sea ice melting. Enhanced nutrient consumption in the glacial subantarctic would have worked to lower the concentration Of CO2 in the ice age atmosphere. It also would have reduced the preformed nutrient content of the low-latitude thermocline, leading to decreases in lowlatitude productivity, suboxia, and denitrification. Copyright 2005 by the American Geophysical Union. 1539 Glacial to interglacial changes in the settling depth of the Mediterranean Outflow plume Rogerson M., Rohling E.J., Weaver P.P.E. and Murray J.W. Paleoceanography 2005 20/3 (1-12) We present micropalaeontological and grain-size records for a set of sediment cores from the Gulf of Cadiz (southwest Spain) that reflect changes in the position and strength of the Mediterranean Outflow (MO) current. The cores sample a sediment drift (the Gil Eanes Drift) that is positioned lower on the slope in the Gulf of Cadiz than the position of the main current today. The data indicate that the drift is of glacial age and that the glacial MO current was positioned lower on the slope than today but also that it was active over a considerably reduced area of the slope. We argue that this observation is consistent with physical constraints on the Gibraltar Exchange and on the likely settling and spreading behavior of the MO plume along the Iberian Margin under glacial environmental and sea level conditions. The deeper settling of the MO is likely to have influenced the formation of glacial North Atlantic Intermediate Water and also may have exerted indirect influence on the formation of glacial North Atlantic Deep Water. Copyright 2005 by the American Geophysical Union. 1540 Ocean climate variability in the eastern North Atlantic during interglacial marine isotope stage 11: A partial analogue to the Holocene? de Abreu L., Abrantes F.F., Shackleton N.J. et al. Paleoceanography 2005 20/3 (1-15) Similar orbital geometry and greenhouse gas concentrations during marine isotope stage 11 (MIS 11) and the Holocene make stage 11 perhaps the best geological analogue period for the natural development of the present interglacial climate. Results 292 THE QUATERNARY of a detailed study of core MD01-2443 from the Iberian margin suggest that sea surface conditions during stage 11 were not significantly different from those observed during the elapsed portion of the Holocene. Peak interglacial conditions during stage 11 lasted nearly 18 kyr, indicating a Holocene unperturbed by human activity might last an additional 6-7 kyr. A comparison of sea surface temperatures (SST) derived from planktonic foraminifera for all interglacial intervals of the last million years reveals that warm temperatures during peak interglacials MIS 1, 5e, and 11 were higher on the Iberian margin than during substage 7e and most of 9e. The SST results are supported by heavier 18 O values, particularly during 7e, indicating colder SSTs and a larger residual ice volume. Benthic 13 C results provide evidence of a strong influence of North Atlantic Deep Water at greater depths than present during MIS 11. The progressive ocean climate deterioration into the following glaciation is associated with an increase in local upwelling intensity, interspersed by periodic cold episodes due to ice-rafting events occurring in the North Atlantic. Copyright 2005 by the American Geophysical Union. 1541 Problems with paleoproductivity proxies Anderson R.F. and Winckler G. Paleoceanography 2005 20/3 (1-7) Difficulties associated with reconstructing past changes in export production were highlighted recently by Averyt and Paytan (2004), who reported substantial disagreement among records developed using different paleoproductivity proxies extracted from two equatorial Pacific piston cores. Proxies included the accumulation rates of barite, excess Ba, and excess as well as elemental ratios of A1/Ti and Ba/Ti. Here we build upon their work by presenting evidence for two factors that contributed to these discrepancies. First, elemental (Ba/Ti and Al/ Ti) ratios are influenced by variability in space and time of the flux of Ti to equatorial Pacific sediments, so these proxies cannot be expected to hold a constant relationship to export production. Second, the late Holocene increase in CaCO3 dissolution has caused concentrations of barite, excess Ba, and excess Al to be enriched in surface sediments relative to the depth interval over which sediment accumulation rates were evaluated in developing the algorithms used by Averyt and Paytan (2004). This produces an error in the accumulation rates of these proxies that varies from core to core, ranging from a few tens of percent to as much as a factor of 3. These errors would have been propagated into the export production algorithms on the basis of fluxes of barite, excess Ba, and excess Al. Furthermore, this bias created by the late Holocene increase in CaCO3 dissolution will affect the development of any algorithm based on fluxes of sedimentary constituents. These factors must be taken into account in future paleoceanographic reconstructions. Copyright 2005 by the American Geophysical Union. 1542 Temporal and spatial variation in tetraether membrane lipids of marine Crenarchaeota in particulate organic matter: Implications for TEX86 paleothermometry Wuchter C., Schouten S., Wakeham S.G. and Sinninghe Damst´e J.S. Paleoceanography 2005 20/3 (1-11) The TEX86 is a new temperature proxy which is based on the number of cyclopentane moieties in the glycerol dialkyl glycerol tetraether (GDGT) lipids of the membranes of Crenarchaeota that occur ubiquitously in oceans and shelf seas. This proxy was calibrated by core top sediments, but it is as yet not clear during which season and at which depth in the water column the GDGT signal used for TEX86 paleothermometry is biosynthesized. Here we analyzed >200 particulate organic matter (POM) samples from 11 different marine settings for TEX86 . This revealed that the GDGTs occur seasonally in surface waters and occur in higher abundances during the winter and spring months. The depth distribution showed that GDGTs generally appeared in higher amounts below 100 m depth in the water column. However, the TEX86 values for waters below the photic zone (150-1500 m) did not correlate with the in situ temperature but rather correlated linearly with surface temperature. The TEX86 for POM from the upper 100 m showed a linear correlation with in situ temperature, which was nearly identical to the previously reported core top equation. The correlation of all POM samples with surface temperature was also strikingly similar to the core top correlation. These findings demonstrate that the GDGT signal which reaches the sediment is mainly derived from the upper 100 m of the water column. This may be caused by the fact that GDGTs from the photic zone are much more effectively transported to the sediment by grazing and repackaging in large particles than GDGTs from deeper waters. Copyright 2005 by the American Geophysical Union. 1543 Reconstruction of paleo-particulate organic carbon fluxes for the Campbell Plateau region of southern New Zealand using the zinc content of sponge spicules Ellwood M.J., Kelly M., Neil H. and Nodder S.D. Paleoceanography 2005 20/3 (1-15) The zinc concentration of siliceous sponge spicules was determined from spicules recovered from four sediment cores spanning the last 160 kyr, from the Campbell Plateau region southeast of New Zealand. Zinc/Si results showed little difference between Holocene and glacial aged spicules. An increase in Zn/Si was observed for core Y14, where Zn/Si peaked at about 0.6 mol/mol during marine isotope stages 5a-5b. To better understand the role carbon export has on sponge Zn/Si, we explored the strong relationship observed between surficial sediment particulate organic carbon (POC) and the Zn/Si of sponge silica and related this to sediment trap POC flux estimates. Conversion of the Zn/ Si records to benthic POC fluxes suggests that there has been little change in the amount of POC reaching Campbell Plateau sediments over the past 30 kyr. These results suggest that surface productivity over the Campbell Plateau has remained relatively low over the past 160 kyr and suggests that glacial productivity was not significantly higher than the present day. Finally, this work reveals that living marine sponges appear to act as the biological equivalents of moored sediment traps, recording the flux of POC to the seafloor by archiving zinc associated with sinking POC in the growing silica skeleton. Copyright 2005 by the American Geophysical Union. 1544 Methane-driven late Pleistocene 13 C minima and overflow reversals in the southwestern Greenland Sea Millo C., Sarnthein M., Erlenkeuser H. and Frederichs T. Geology 2005 33/11 (873-876) A core transect across the southwestern Greenland Sea reveals coeval events of extremely negative planktic and benthic 13 C excursions between 40 and 87 ka. The most pronounced event, event 1, began at peak Dansgaard-Oeschger stadial 22 (85 ka) with a duration of 18 k.y. During this episode, incursions of Atlantic Intermediate Water caused a bottom-water warming of up to 8°C. The amplitude, timing, and geographic pattern of the 13 C events suggest that this bottom-water warming triggered clathrate instability along the East Greenland slope and a methane-induced depletion of 13 CDIC (DIC - dissolved inorganic carbon). Since 13 C event 1 matches a major peak in atmospheric CH concen4 tration, this clathrate destabilization may have contributed to the rise in atmospheric CH4 and thus to climate warming over marine isotope stage 5.1. © 2005 Geological Society of America. 1545 Late Quaternary paleoenvironmental changes in the southeastern Yellow Sea, Korea Kong G.S., Park S.- C., Han H.C. et al. Quaternary International 2005 144/1 (38-52) A 34-meter-long AMS 14 C-dated sediment core was examined in order to reconstruct the paleoenvironmental changes that have taken place in the southeastern Yellow Sea during the last 16,600 years. To achieve this, we analyzed the geochemical compositions of organic matter, the benthic foraminiferal assemblages, and the stable isotopes of benthic foraminiferal tests. The organic geochemical results show that terrigenous organic matter was dominant in the southeastern Yellow Sea between 16,600 and 4300 cal. yr BP, probably due to the influence of river runoff; marine organic matters, originating from surface primary productivity, began increasing drastically after 4300 cal. yr BP. Benthic foraminiferal assemblages reveal that brackish species were dominant before 3500 cal. yr BP, but the saline species dominated after this time. The 18 O values of the benthic foraminifer Cibicides lobatulus showed that a change from high-amplitude to low-amplitude fluctuations took place at 3500 cal. yr BP. These multi-results indicate that the southeastern Yellow Sea changed from an estuarine to a modern marine shelf environment, proba- THE QUATERNARY bly due to the inflow of the Yellow Sea Warm Current, between 4300 and 3500 cal. yr BP. The time discrepancy of 800 years indicates that a modern marine shelf environment was not fully developed in the southeastern Yellow Sea until 3500 cal. yr BP, even though the sea began to be influenced by the oceanic current at 4300 cal. yr BP. © 2005 Elsevier Ltd and INQUA. All rights reserved. Tropics and sub-tropics 1546 Modern pollen spectra from the highlands of the Cordillera Central, Dominican Republic Kennedy L.M., Horn S.P. and Orvis K.H. Review of Palaeobotany and Palynology 2005 137/1-2 (51-68) We studied pollen, spores, and pine stomata in surface pond and bog sediments and surface soils to characterize modern pollen deposition in highland plant communities of the Cordillera Central, Dominican Republic. We collected our samples at 47 sites representing a range of elevations (1200-3000 m) and cover types on both the windward and leeward flanks of the cordillera. Pollen from the endemic West Indian pine dominated surface spectra in nearly all forested sites, as well as in most grasslands. Detrended correspondence analysis (DCA) revealed that the modern pollen spectra of forested uplands and open wetland sites are clearly distinct, while other site types that are intermediate in terms of vegetation are also intermediate in terms of modern pollen spectra. The DCA also separated windward from leeward sites based mainly on higher pollen percentages of broadleaf trees and shrubs in the windward sites. A lack of pine stomata was an excellent indicator of treelessness in grassland sites. This clear distinction between treeless and forested sites may be useful in interpreting highland fossil records that date to the last glacial period. © 2005 Elsevier B.V. All rights reserved. 1547 Stratigraphical and palynological appraisal of the Late Quaternary mangrove deposits of the west coast of India Kumaran K.P.N., Nair K.M., Shindikar M. et al. Quaternary Research 2005 64/3 (418-431) The organic deposits derived from the mangrove swamps form reliable stratigraphic markers within the Late Quaternary sequence of Kerala - Konkan Basin. Three generations of such deposits have been identified. The older one is dated to around 43,000-40,000 14 C yr B.P., with a few dates beyond the range of radiocarbon. The younger ones date from the Middle Holocene to latest Pleistocene (10,760-4540 14 C yr B.P.) and the Late Holocene (<4000 14 C yr B.P.). Pollen analyses confirm that the deposits are mostly derived from the mangrove vegetation. Peat accumulation during the period 40,000-28,000 14 C yr B.P. can be correlated with the excess rainfall, 40-100% greater than modern values, of the Asian summer monsoon. The low occurrence of mangrove between 22,000 and 18,000 14 C yr B.P. can be attributed to the prevailing aridity and/or reduced precipitation associated worldwide with Last Glacial Maximum, because exposure surfaces and ferruginous layers are commonly found in intervals representing this period. The high rainfall of 11,000-4000 14 C yr B.P. is found to be the most significant as the mangrove reached an optimum growth around 11,000 14 C yr B.P. but with periods of punctuated weaker monsoons. From the present and previous studies, it has been observed that after about 5000 or 4000 14 C yr B.P., the monsoons became gradually reduced leading to drying up of many of the marginal marine mangrove ecosystems. A case study of Hadi profile provided an insight to the relevance of magnetic susceptibility (x) to record the ecological shift in Late Holocene. © 2005 University of Washington. All rights reserved. 1548 How a wet tropical rainforest copes with repeated volcanic destruction Jago L.C.F. and Boyd W.E. Quaternary Research 2005 64/3 (399-406) The Holocene Period for the province of West New Britain, Papua New Guinea, is characterised by periodic catastrophic volcanism. The region is mantled in dense wet tropical rainforest, and has been occupied by people since the Pleistocene. Analyses of peat from two nearby sites within a lowland rainforest environment 293 provide us with a macro-level landscape account of the periodic destruction and recovery of the coastal forests during seven periods of volcanic activity in the latter part (2900 yr ago to present) of the Holocene. Radiocarbon dating shows the very close correlation of the peat and tephra layers at both sites, yet the pollen analysis reveals different vegetation communities. These initial results allow us to begin identifying the processes of recovery, and to recognise different ecological pressures placed on vegetation at these neighbouring sites. Evidence of hydrological changes are observed beginning with a marine incursion recorded at Garu Site 3 1360 14 C yr B.P. The distinct differences in the vegetation re-establishment and community regeneration rates suggest the greater level of disturbance at Garu Site 1 could be related to the depth of the ashfall, although the proximity of a known human settlement may also be a contributing factor. Of note, palynologically, we found that the fern spore flora is particularly rich and believe it will be useful for ecological interpretation. © 2005 University of Washington. All rights reserved. Mid-latitude and extra-glacial 1549 Estimating relevant source area of pollen for small Danish lakes around AD 1800 Nielsen A.B. and Sugita S. Holocene 2005 15/7 (1006-1020) The aims of this study were to obtain estimates of the relevant source area of pollen (RSAP) that can be used to interpret fossil pollen diagrams from medium sized lakes, and to elucidate factors affecting RSAP for such lakes. A data set of sediment pollen assemblages dating from AD 1800 from 25 Danish lakes (3-27 ha) and land cover around the same lakes from historical maps was used. The plant abundance data were distance weighted using a species-specific model of pollen dispersal/deposition and other distance weighting functions (1, 1/d and 1/d2 ). Extended R-value models were applied to evaluate the relationship between pollen and plant abundance and to estimate RSAP. The choice of distance weighting function influenced the RSAP estimates. When using the species-specific model, wind speed and speciesspecific properties of pollen dispersal had little effect on the RSAP estimates, which were approximately 1700 m in radius, when all lakes were analysed together. When the pollen types were classified into fewer groups, the RSAP estimate increased, probably because this procedure affected the spatial pattern of the plant abundance data by, in effect, increasing patch size. When the lakes were classified into two distinct groups (western Jutland and remaining sites) using a multivariate statistical technique (TWINSPAN), we obtained different RSAP estimates for each of the two groups. This result could be explained by a difference in average patch size of the land cover types between regions. A series of simulations supported our interpretation that the patch size was the main factor determining the size of the RSAP for the Danish lakes at AD 1800. © 2005 Edward Arnold (Publishers) Ltd. 1550 Aeolian sand preserved in Silver Lake: A new signal of Holocene high stands of Lake Michigan Fisher T.G. and Loope W.L. Holocene 2005 15/7 (1072-1078) Aeolian sand within lake sediment from Silver Lake, Michigan can be used as a proxy for the timing of high lake levels of Lake Michigan. We demonstrate that the sand record from Silver Lake plotted as percent weight is in-phase with the elevation curve of Lake Michigan since the mid-Holocene Nipissing Phase. Because fluctuations in Lake Michigan’s lake level are recorded in beach ridges, and are a response to climate change, the aeolian sand record within Silver Lake is also a proxy for climate change. It appears that increases in dune activity and lake sand are controlled by similar climatic shifts that drive fluctuations in lake level of Lake Michigan. High lake levels destabilize coastal bluffs that drive dune sand instability, and along with greater wintertime storminess, increase niveo-aeolian transport of sand across lake ice. The sand is introduced into the lake each spring as the ice cover melts. © 2005 Edward Arnold (Publishers) Ltd. 294 THE QUATERNARY 1551 Holocene paleosols of the Upo wetland, Korea: Their implications for wetland formation Nahm W.- H., Kim J.- K., Yang D.- Y. et al. Quaternary International 2005 144/1 (53-60) A 4.490 m long core UP-1 was recovered from the marginal part of the Upo wetland. The wetland is a typical riverine wetland in Korea and has been designated as a Protected Wetland in accordance with the International Ramsar Treaty. We studied the Holocene environmental changes of the Upo wetland and the depositional conditions under which the Upo wetland formed. The core is divided into four units on the basis of grain size distribution, abundance of mottles and vertical color variation. Unit 1 has undergone pedogenic processes, resulting in variably weak to moderate soil profile development. Unit 1 paleosols are regarded as synsedimentary soils of floodplain origin, and the radiocarbon data suggest that the whole paleosol profile spans the last 5790 years. The boundaries between the soil horizons are not clear-cut, probably due to a repeated cycle of accumulation, denudation and soil-forming processes. The recurrence of these processes initiated the development of the Upo wetland. The lower boundary of Unit 2 lies at about 2300 14 C yr BP, the beginning of the Subatlantic age in Korea. The lack of intense soil formation and abundant clay content in Unit 2 indicate that the geomorphologically stable wetland was developed around the coring site at that time. This means that the depositional environment changed from a floodplain to a stable, continuously submerging wetland setting. An abrupt change in sediment textures was detected in Unit 3, which commenced formation around 1000-900 14 C yr BP, indicative of geological events such as inundations or inflows of slope-wash sediments. Anthropogenic deforestation and plowing around the Upo wetland area might have started at that time. © 2005 Elsevier Ltd and INQUA. All rights reserved. 1552 A comparison of late Quaternary forest changes in New Caledonia and northeastern Australia Stevenson J. and Hope G. Quaternary Research 2005 64/3 (372383) A pollen record from Lake Xere Wapo, southeast New Caledonia, is the longest continuous terrestrial record to be recovered from the tropical southwest Pacific and reveals a series of millennial scale changes in vegetation over the last 130,000 yr. A comparison of the Lake Xere Wapo record with the key northeast Australian record of Lynch’s Crater reveals regional patterns of change. From 120,000 to 50,000 yr ago the vegetation around Lake Xere Wapo alternated between rainforest and maquis with fire an important disturbance factor. In the last 50,000 yr fire is almost absent from the record and the vegetation assumes a character unprecedented in the preceding 100,000 yr, dominated by Dacrydium and Podocarpus pollen. The most compelling aspect of the comparison with Lynch’s Crater is that the muchdiscussed Araucaria decline at around 45,000 yr ago in northern Queensland is matched by a similar decline in the Lake Xere Wapo record. © 2005 University of Washington. All rights reserved. Glacial landforms and sediments 1553 A complex subglacial clastic dyke swarm, S´olheimaj¨okull, southern Iceland Le Heron D.P. and Etienne J.L. Sedimentary Geology 2005 181/12 (25-37) A complex network of clastic dykes dissects loosely consolidated Holocene sediments along the east flank of the proglacial braid plain of S´olheimaj¨okull, southern Iceland. The dykes comprise downward-bifurcating intrusions up to 0.5 m thick and several metres in length and are intruded into glaciogenic deposits (sandy gravel, gravelly sand, interlaminated silt and sand, and diamicton). The dykes were sourced from a clast-poor sandy diamicton, interpreted as a subglacial till, and were intruded downwards beneath S´olheimaj¨okull glacier during a previous phase of advance. As the glacier advanced southwards, it loaded the sediment column resulting in the intrusion of dykes with a consistent south-southwest dip (with rare northward-dipping examples). The dyke fills are characterised by laminated sed- iment, with laminae oriented parallel to the dyke margins and comprise interlaminated clay, silty clay, silt, sand, sandy gravel and diamicton. In some dykes, high concentrations of pebble- to boulder-sized clasts occur in association with rotated pods of the laminated sediment. The laminae are thought to have evolved by a slow, long-lived intrusion process that involved the repeated fracture and expansion of the host sediments followed by viscous smearing-on of subglacial material onto the dyke walls, rather than rapid injection of fluidised sediment. © 2005 Elsevier B.V. All rights reserved. 1554 3-D sedimentary architecture of a Quaternary gravel delta (SW-Germany): Implications for hydrostratigraphy Kostic B., Becht A. and Aigner T. Sedimentary Geology 2005 181/3-4 (147-171) This paper investigates a Quaternary Gilbert-type gravel delta that was formed in an ice-marginal environment at the end of the last glacial period. Outcrop, sediment core and groundpenetrating radar (GPR) studies reveal the sedimentary facies and depositional architecture of the delta that comprises three major units: (1) a 2-5 m thick, gravelly topset with an erosional base, formed by accretion of bedload sheets in a braided river; (2) an up to 40 m thick, steeply inclined (13-35°) foreset, dominated by gravelly lithofacies being the product of cohesionless debris flows and debris falls as well as gravity slides while sandy lithofacies was deposited by traction currents; and (3) a 10-20 m thick, sandy bottomset comprising low-density turbidites. Syn- to postdepositional deformation of parts of the bottomset deposits largely resulted from rapid deposition of overlying gravels and differential loading of the prograding foreset beds. The development of the delta was most likely controlled by a high sediment supply and lake level fluctuations. The overall coarsening-upward succession reflects delta progradation and aggradation into a glaciolacustrine environment. Outcrop sedimentology served as a direct analogue in order to characterise the three-dimensional sedimentary and hydraulic architecture of the nearby gravel-delta aquifer. Applying a multidisciplinary approach, sedimentological, geophysical, and hydrogeological data were integrated within the 3-D modelling package Gocad (Earth Decision Sciences) to develop high-resolution 3-D aquifer models. © 2005 Elsevier B.V. All rights reserved. 1555 Evolution of the southern Barents Sea framing in the Late Pleistocene Tarasov G.A. and Matishov G.G. Doklady Earth Sciences 2005 404/7 (1093-1096) The Late Pleistocene was characterized by the growth and degradation of continental and, sometimes, marine ice sheets in the Northern Hemisphere. These processes were responsible for the main global changes that occurred on the continents and in the ocean and atmosphere. The study region is a key one for the study of unclear and controversial problems concerning the reconstruction of deglaciation conditions and postglacial environmental changes. The present communication is based o n results of the lithological study of the offshore borehole sections of bays, shelf zones, and lacustrine depressions in the northern Kola and Kanin peninsulas. We also used data from morphostructural and geomorphological observations, dendrochronological analysis (Pinus silvestris), radiocarbon datings, 10 Be and 26 Al isotopic datings in quartz-bearing rocks, and other materials. The study region is large. Moreover, its geological-geomorphological structure and physicogeographic conditions sharply vary from east to west. Therefore, it is reasonable to consider the main natural peculiarities separately for each of the examined areas. Copyright © 2005 by Pleiades Publishing, Inc. 1556 Strandline analysis in the southern basin of glacial Lake Agassiz, Minnesota and North and South Dakota, USA Fisher T.G. Bulletin of the Geological Society of America 2005 117/11-12 (1481-1496) Glacial Lake Agassiz, a large Pleistocene lake, left behind strandlines at multiple elevations within its basin. Prior researchers have used these strandlines to identify four relatively stable water level stages, but tracing them over long distances is often problematic. In this study, the elevation of the Tintah strandline is returned to its original designation, and a newly interpreted stable lake level at 1020-1030 ft (311-314 m) is referred to as THE QUATERNARY the Upham level, based on a concentration of ridges and a spit at that elevation. Cores from strandline and lagoon complexes from the Milnor to Tintah beaches reveal a decreasing thickness of strandline sediment associated with shorter aggregate-length strandlines. This relationship is most likely controlled by sediment starvation, greater water level fluctuations and shallower water. Beaches near the head of the southern outlet spillway indicate that shoreline occupation at the Lower Campbell level was either very short-lived or strandline development was hampered by shallow water. The modern-day sill elevation between the southern outlet spillway and the lake basin is found to be 3 km south of White Rock, Minnesota, at an elevation of 974 ft (297 m). All but the Campbell strandlines at the southern outlet are interpreted as the result of a regression driven by incision of the southern outlet spillway. © 2005 Geological Society of America. The Holocene 1557 Archaeological evidence for the first Mesolithic occupation of the Western Isles of Scotland Gregory R.A., Murphy E.M., Church M.J. et al. Holocene 2005 15/7 (944-950) The examination of eroding coastal dunes at the prehistoric site of Northton, Harris, has produced the first archaeological evidence of Mesolithic activity in the Western Isles in the form of two midden-related deposits. The first phase of Mesolithic activity is dated to 7060-6650 cal. BC based on AMS dating of charred hazelnut shells. This discovery appears to validate the frequent pollen-based inferences of Mesolithic impact for the area and, as predicted, allows the Atlantic fringe of Scotland to become part of the European Mesolithic mainstream. A detailed pedological analysis also suggests that these early midden layers may have been amended during the Neolithic period as part of a possible phase of cultivation. © 2005 Edward Arnold (Publishers) Ltd. 1558 Late-Holocene environmental variability at Munsa archaeological site, Uganda: A multicore, multiproxy approach Lejju B.J., Taylor D. and Robertshaw P. Holocene 2005 15/7 (1044-1061) Palaeoenvironmental data, in the form of 113 counts of pollen, fungal spores and charcoal abundances, 121 counts of phytoliths and 15 AMS 14 C dates (11 macrofossil and 4 bulk sediment samples), have provided a means of reconstructing the late-Holocene environmental history of Munsa archaeological site, Uganda. The data were extracted from sediment cores from what is today a papyrus swamp, located within an area described by an outermost ring of earthworks at Munsa. Sediment core data indicate the general presence of forested conditions to c. AD 1100, although there is evidence for the local presence of food plants prior to this date. Deforestation from c. AD 1100 is marked in both the pollen and phytolith records, while fungal spores indicate the presence of increased numbers of herbivores post-deforestation. Indicators of deforestation and increased herbivore numbers broadly accord with the archaeological evidence for substantial occupation of the site at Munsa and the establishment of a mixed economy based on crops, cattle and iron working. Evidence for forest recovery and reduced herbivore numbers locally from c. AD 1780 could reflect abandonment of permanent settlement at the site, possibly during or following a period of drought and/or political upheaval in the region. Fungal spores and phytoliths provide evidence of agricultural activities at Munsa that have not left an imprint on pollen records, thus supporting the case for the use of multiproxies in palaeoenvironmental research, while intercore differences between the three sediment cores analysed, although relatively minor, confirm the benefits of a multicore approach. Tentative evidence for the very early presence of Musa (cultivated edible banana) is provided and warrants further study. © 2005 Edward Arnold (Publishers) Ltd. 1559 Tephra-dated climate- and human-impact studies during the last 1500 years from a raised bog in Central Ireland Hall V.A. and Mauquoy D. Holocene 2005 15/7 (1086-1093) Historic Icelandic tephrochronology constrains the time frame of a plant macrofossil and palynological study of ombrotrophic 295 peat to evaluate the effects of climatic and human impact over the last 1500 years on the landscape at a large monastic site in the Irish Midlands. The plant macrofossil climate proxy record indicates maximum wetness during the sixth century AD. Decreasing wetness occurred from the late ninth century to the late thirteenth century. From c. AD 1290 to 1830, the plant macrofossils record a reduction in mire surface wetness and there is no evidence for ‘Little Ice Age’ climatic deteriorations. The pollen analytical evidence indicates an agricultural system dominated by pastoralism throughout the first millennium AD with arable agriculture increasing in the closing years of the first millennium and throughout the second millennium AD. From the eighteenth century onward, agricultural land use expands with a concomitant reduction in scrub. © 2005 Edward Arnold (Publishers) Ltd. 1560 An evaluation of multielement analysis of historic soil contamination to differentiate space use and former function in and around abandoned farms Wilson C.A., Davidson D.A. and Cresser M.S. Holocene 2005 15/7 (1094-1099) Historic and prehistoric human activity can cause accumulation of elements in the soil. Multielement soil analysis has been used extensively over the last two decades to study element patterns of historic soil enrichment as a means of prospecting for sites and as an aid to interpretation of space use within archaeological structures. However, there have been surprisingly few of studies designed to assist with the interpretation of the analytical results. In this investigation soils from six abandoned farms with a known history of spatial use were sampled to determine if similar patterns of trace element enhancement occur between different farms. The preliminary results show significant differences in soil elemental concentrations between the functional areas, and highlight similar patterns of element enhancement between the farms. Concentrations of Ca, P, Sr, Ba, Zn and Pb are elevated in the buildings and fields of all the farms and provide valuable information about past human activity. © 2005 Edward Arnold (Publishers) Ltd. 1561 High-resolution reconstruction of a 1300 year old gully system in northern Bavaria, Germany: A basis for modelling long-term human-induced landscape evolution Dotterweich M. Holocene 2005 15/7 (994-1005) Knowledge of historical gullying and long-term processes of interactions between land use and gullying is still rather limited. Here, I review results from case studies in Germany and neighbouring countries and exmine the complex development of a gully system in northern Bavaria, integrating land-use changes and their interactions within a conceptual model. Reconstructions of gully development were made by identifying and dating sediment layers, artificial modifications and soil horizons at high spatial and temporal resolution, combined with analyses of historical documents. The case study in northern Bavaria shows that more than 150 colluvial layers found in a gully system revealed the detailed history of gully development during the last 1300 years. The first gullying took place in early Mediaeval times during several heavy rainfall events but the main phases of gullying took place between the fourteenth and the mid-eighteenth centuries. Occurrence of gullying was strongly linked to phases of high land-use intensity, which later changed the runoff pattern and enlarged the catchment area by 50%. Subsequently, overflowing field furrows led to the development of two gullies, up to 6 m deep, in late Mediaeval and early modern times. From the middle of the nineteenth century until today, only a little soil erosion has taken place and most of the catchment area has become grassland or forest. During the 1050 years from AD 800 to 1850, a soil volume of about 6430 m3 was eroded by gullying, destroying 15% of the arable land. The results provide a basis for modelling long-term human-induced landscape evolution. © 2005 Edward Arnold (Publishers) Ltd. 296 THE QUATERNARY 1562 A new step towards a synthesis of the Holocene history of the vegetation of the Monts de la Madeleine, Forez Livradois and Pilat (Eastern Massif central, France) (French) (L’´evolution Holoc`ene de la v´eg´etation des monts de la Madeleine, du Forez, du livradois et du pilat (Massif central oriental, France): L’apport d’une nouvelle s´erie d’analyses palynologiques) Argant J. and Cubizolle H. Quaternaire 2005 16/2 (119-142) In France, many fens and peat bogs are located in the granitic eastern part of the Massif central. In this area peat formation was determined by the climate with abundant rainfalls - from 1000 to 1500 mm above an altitude of 1000 m a.s.l. - a fair distribution of this rainfalls over the year, the topography with shallow headwaters areas, small hollows with concave bottoms and the geomorphology with glacial and periglacial land forms and deposits. During the last sixty years several pollen analysies, discussed in that paper, allows the reconstruction of the vegetation of this area back to the end of the Lateglacial. But the most ancient studies are not so precise as those of today and have often either few or even no radiocarbon dates. All these studies have not been published. So, four new analysies were undertaken on three peat bogs and one fen. They are supported by 32 14 C dates which allows us to be precise about the former available data. They are part of global research including palaeoenvironmental reconstruction, understanding the origin of the great number of holocene mires and evaluation of the role of Man in the landscape evolution since the prehistoric time. Pollen analysis shows that the changes in vegetation are very similar to what is known elsewhere in the Massif central, except in the Massif du Pilat where the dynamics of Fagus and Abies is quite different. Human influence can be noted since the end of the Atlantic period (Middle Neolithic, about 5500 cal. BP) and the numerous radiocarbon dates make it possible to have an accurate chronology and they give us a better understanding of the occupancy of the middle-range-mountain in the past. 1563 13 C variation of C3 and C4 plants across an Asian monsoon rainfall gradient in arid northwestern China Liu W., Feng X., Ning Y. et al. Global Change Biology 2005 11/7 (1094-1100) We have investigated carbon isotopic compositions of four plant genus/species, Bothriochloa ischaemum (C4 ), Stipa bungeana (C 3 ), Lespedeza sp. (C3 ) and Heteropappus less (C 3 ), along a precipitation gradient in northwest China in order to assess the impact of water availability on the carbon isotopic discrimination against 13 C during carbon assimilation in this area. This information is necessary for reconstruction of paleovegetation, particularly paleo-C 3 /C4 plant ratios using 13 C value of organic matter in loess and paleosols in the Chinese Loess Plateau. The 13 C of C plants, as a group, exhibits a negative correlation with 3 the annual precipitation amount with a total change and sensitivity of 5%o and -1.1%o/100 mm, respectively, for the precipitation range from 200 to 700mm. The C4 grass, B. ischaemum responds to aridity by decreasing 1.7%o for over the precipitation range from 350 to 700 mm; the plant 13 C is significantly correlated with annual precipitation with a slope -0.61%o/100 mm. This result implies that without considering the effect of water availability on the plant 13 C values, reconstruction of percent C4 vegetation during the last glaciation can be overestimated by about a factor of two. © 2005 Blackwell Publishing Ltd. 1564 Climate change and human impact on the Song Hong (Red River) Delta, Vietnam, during the Holocene Li Z., Saito Y., Matsumoto E. et al. Quaternary International 2005 144/1 (4-28) On the basis of the results of palynological research on two cores from the Song Hong (Red River) delta in the sub-tropical zone of Asia, centennial- to millennial-scale climate changes and human impacts during the Holocene were clarified. Three cycles of cooling and warming were identified during the last 5000 yr: a cool and wet climate during 4530-3340 cal. yr BP, 2100-1540 cal. yr BP, and 620-130 cal. yr BP, a warm and dry climate during 3340-2100 cal. yr BP, 1540-620 cal. yr BP and the present warm climate. The first and last cooling events correspond to global Holocene cooling events, the Neoglacial Period and the Little Ice Age, respectively. Each persisted for 500-1000 yr, and they occurred at intervals of 1500-2000 yr. Pollen records also reflect human impacts on this area, which intensified after 3340 cal. yr BP when large quantities of cultivated Gramineae taxa, possibly including the main wet rice species, Oryza sativa, secondary forest, and other upland cultivated taxa appear in the record. © 2005 Elsevier Ltd and INQUA. All rights reserved. 1565 Quantification strategies for human-induced and natural hydrological changes in wetland vegetation, southern Florida, USA Donders T.H., Wagner F. and Visscher H. Quaternary Research 2005 64/3 (333-342) An accurately dated peat profile from a mixed cypress swamp in the Fakahatchee Strand Preserve State Park (FSPSP, Florida, USA) has been examined for pollen and spores. The near-annual resolved pollen record shows a gradual shift from a wet to a relatively dry assemblage during the past 100 years. Timing of drainage activities in the region is accurately reflected by the onset and duration of vegetation change in the swamp. The reconstructed vegetation record has been statistically related to pollen assemblages from surface sediment samples. The response range of the FSPSP wetland to environmental perturbations could thus be determined and this allows better understanding of naturally occurring vegetation changes. In addition, the human impact on Florida wetlands becomes increasingly apparent. Superimposed high-frequency variation in the record suggests a positive correlation between winter-precipitation and pollen productivity of the dominant tree taxa. However, further high-resolution analysis is needed to confirm this relation. The response range of the FSPSP wetland to environmental perturbations on both annual- and decadal-scales documented in this study allows recognition and quantification of natural hydrological changes in older deposits from southwest Florida. The strong link between local hydrology and the El Ni˜no Southern Oscillation makes the palynological record from FSPSP highly relevant for studying past El Ni˜no - variability. © 2005 University of Washington. All rights reserved. 1566 The stratigraphy and fire history of the Kutai Peatlands, Kalimantan, Indonesia Hope G., Chokkalingam U. and Anwar S. Quaternary Research 2005 64/3 (407-417) The equatorial peatlands of the Kutai lowland of eastern Kalimantan are generally 4-10 m in thickness but some sections exceed 16 m in depth. The deposition of peat commenced about 8000 yrs ago after shallow flooding of the basin by the Mahakam River. The earliest vegetation is a Pandanus swamp which grades upwards to swamp forest dominated by dipterocarps. The peatland has expanded laterally and rivers have maintained narrow leveechannel tracks through the swamp, which has grown vertically in balance with river accretion. Historical fires are associated with extreme El Ni˜no years of drought, but human agency is important. The fires of 1982-1983 and 1997-1998 burnt up to 85% of the vegetation on the peatland. Although charcoal analyses show that fire has occurred throughout the history of the peatland, it is rare in forests remote from rivers until the last 3000 years and only common within the last millennium. Fires are earlier and more frequent in sites accessible from waterways, and floodplains have been widely burnt down to water table or below, forming extensive lakes. © 2005 University of Washington. All rights reserved. 1567 Vegetation change in the coastal-lowland rainforest at Avai’o’vuna Swamp, Vava’u, Kingdom of Tonga Fall P.L. Quaternary Research 2005 64/3 (451-459) Avai’o’vuna Swamp, a small coastal wetland in Vava’u, Kingdom of Tonga, produced a 4500-year pollen and sediment record. Results are: (1) a mid-Holocene sea level highstand is confirmed for Tonga between about 4500 and 2600 14 C yr B.P.; marine clay contains pollen from mangroves (Rhizophora mangle), coastal forest trees (Barringtonia asiatica and Cocos nucifera), and rainforest trees (Alphitonia, Rhus, Hedycarya and Calophyllum). (2) Microscopic charcoal first appeared at 2600 14 C yr B.P., coincident with the arrival of Polynesians. (3) Cocos, Pandanus, Excoecaria, Macaranga, and Elaeocarpaceae pollen reflects the establishment of a mixed coastal-lowland rainforest in the last 2500 years. (4) The loss of Hedycarya, Elaeocarpus, Calophyl- THE QUATERNARY lum, and Guettarda and the reduction of Terminalia and taxa in the Papilionaceae family by about 1000 years ago may be due to habitat destruction and the loss of dispersal capabilities of some species through the extinction of the two largest pigeons in Tonga. © 2005 University of Washington. All rights reserved. 1568 Cultivation and human impact at 6000 cal yr B.P. in tropical lowland forest at Niah, Sarawak, Malaysian Borneo Hunt C.O. and Rushworth G. Quaternary Research 2005 64/3 (460-468) This paper describes palynological evidence for what appears to be comparatively large-scale human impact in the catchment of the Sungai Niah in the wet tropical lowland swamp forests of Sarawak, Malaysian Borneo close to the Great Cave of Niah. Pollen associated with cleared landscapes and rice cultivation is evident in the sedimentary record from before 6000 cal yr B.P. Human activity seems to have been associated with changes in sedimentary regime, with peat-dominated environments being replaced diachronously by clay-dominated deposition. This may reflect anthropogenic soil erosion in the catchment of the Sungai Niah. © 2005 University of Washington. All rights reserved. 1569 Holocene dryness and human occupation in Brazil during the "Archaic Gap" Araujo A.G.M., Neves W.A., Pil´o L.B. and Atui J.P.V. Quaternary Research 2005 64/3 (298-307) An overview of the archaeological data produced over the last decades for Brazil, coupled with a background of recent paleoenvironmental studies, suggests that during the mid-Holocene vast areas of Central Brazil ceased to be occupied by human groups. Independent data from dated human skeletons, rock-shelter stratigraphy, and chronology of open-air sites converge to support the inference that these areas were depopulated or altogether abandoned. Paleoenvironmental data suggest that dryness events constitute the major cause behind the observed trends. This phenomenon expands the already perceived notion that climatic stresses had a major role in the shaping of human settlement patterns in marginal environments, such as deserts and high-altitude settings. © 2005 University of Washington. All rights reserved. 1570 Interactions between human activity, volcanic eruptions and vegetation during the Holocene at Garua and Numundo, West New Britain, PNG Boyd W.E., Lentfer C.J. and Parr J. Quaternary Research 2005 64/3 (384-398) This paper reviews recent fossil phytolith analysis from wet tropical West New Britain (Papua New Guinea). The Holocene vegetation has been influenced by spatially and temporally diverse patterns of both prehistoric human settlement and catastrophic volcanic events. We have hypothesized different landscape responses and recovery pathways to events during the last six millennia. Phytolith sequences on the coastal lowlands, the Willaumez Peninsula, and nearby island of Garua provide details of vegetational change and human interactions at different landscape scales since c. 5900 cal yr B.P. During this period four major volcanic eruptions (c. 5900, 3600, 1700 and 1400 cal yr B.P.) have disrupted the landscape. The evidence provides detailed descriptions of temporal and spatial patterning in the impacts and changes in the vegetation. In particular, vegetation responded differently from one event to another, reflecting both forest recovery from seed bank and shooting, and the influence of prehistoric people on recovering vegetation. Furthermore, after some events landscape recovery was moderately uniform, while after others there was considerable landscape partitioning. Although these differences largely relate to airfall tephra type, distribution and magnitude, the partitioning is more strongly influenced by human activity. © 2005 University of Washington. All rights reserved. Periglacial 1571 Pleistocene cryostructures and landslide at Petit-Bost (southwestern France, 45°N) Bertran P. and Fabre R. Geomorphology 2005 71/3-4 (344-356) 297 Remnants of a Pleistocene landslide have been observed during field investigations of Quaternary alluvial formations of the Isle River at Petit-Bost, southwestern France. The main features of the landslide-induced deformation give a good indication of its size and depth. The surface of rupture is located in a 0.5 m thick, very plastic mottled clay at the top of an alluvial gravel. The clay is overlain by 1.7 m thick loamy colluvial deposits with a polygonal net of bleached wedges that testify to past permafrost conditions. The mechanical parameters used in stability calculations for the case of an infinite planar sliding surface, that fits well the geomorphological data, are given by triaxial tests. Stability calculation indicates that the slope is very stable at present and that rupture can only have occurred in fully unconsolidated and undrained conditions. This likely happened during permafrost degradation and subsequent thawing of ice-rich soil layers. Oedometric tests indicate post-sliding over-consolidation of the clay. With regards to the debate on permafrost distribution in France during the Pleistocene, this study gives support to a wide extent of permafrost, at least to the latitude 45°N southward, during the coldest periods. It also points out that frost-induced slope instability may have played a major, but still underestimated, role in many French regions north to this latitude. © 2005 Elsevier B.V. All rights reserved. Glaciology 1572 Holocene glacier chronology of Valenzuela Valley, Mendoza Andes, Argentina Espizua L.E. Holocene 2005 15/7 (1079-1085) Glacial geologic evidence and radiocarbon-dated glacial deposits provide evidence of glacier fluctuations during the last 5 ka years in the Andes. Radiocarbon-dated moraines, morphological and stratigraphical studies permit the reconstruction of glacier fluctuations during the Holocene in the Valenzuela area of the Mendoza Andes valley located at 35°S, in the upper Rio Grande basin. The Holocene record in this part of the Andes is mostly unknown, so this research is relevant for palaeoclimatic reconstructions in South America. In the Ro Valenzuela, glacier variations were dated in the El Azufre and El Pe˜no´ n valleys. The first Neoglacial advance occurred at c. 5700 yr BP and a very close re-advance of similar magnitude occurred at 4700-4300 yr BP which formed well-preserved lateral-terminal moraines. The first Neoglacial advance occurred in the El Pe˜no´ n valley at c. 4400 yr BP and a well-preserved terminal moraine is observed. A second Neoglacial advance reached its maxima at c. 2500-2200 yr BP in the El Azufre and El Pe˜no´ n glaciers. A third, corresponding to the ‘ittle Ice Age’, culminated at c. 400 yr BP (c. AD 1451-1641 cal. yr) and 350 60 yr BP (c. AD 1460-1644 cal. yr) in the El Azufre valley. The third Neoglacial advance is distinguished in the El Pe˜no´ n valley based on morphological characteristics, colour, freshness of the glacial deposits and the proximity to the active glacier. It is indicated by the Amarilla I, II, III lateral moraines. An estimation of the magnitude of snowline depression is obtained comparing the altitude of the present snowline with that of the reconstructed snow line for the first Neoglacial and ‘Little Ice Age’ advances. © 2005 Edward Arnold (Publishers) Ltd. 1573 An alternative form for the statistical distribution of extreme avalanche runout distances Keylock C.J. Cold Regions Science and Technology 2005 42/3 (185-193) There are two main approaches in the avalanche literature for the statistical characterisation of extreme avalanche runout and these are known as the alpha-beta and runout ratio methods. Recent work suggests that the latter method is a more robust approach. This paper examines the statistical reasoning behind the selection of the Extreme Value Type I or Gumbel distribution used to characterise the runout distribution in the runout ratio method. On the basis that a threshold is often applied to the distribution of extreme avalanches used in analysis, it is proposed that the Generalised Pareto Distribution is an appropriate candidate distribution based on theoretical arguments. Such a proposal is tested against data on extreme avalanches in Iceland for both the largest events on specific paths and for all events exceeding a threshold. The latter is a peaks-over-threshold approach that 298 THE QUATERNARY potentially allows more robust distribution estimation due to the increase in data availability. © 2005 Elsevier B.V. All rights reserved. 1574 Greenland mass balance from GRACE Velicogna I. and Wahr J. Geophysical Research Letters 2005 32/18 (1-4) We use 22 monthly GRACE (Gravity Recovery and Climate Experiment) gravity fields to estimate the linear trend in Greenland ice mass during 2002-2004. We recover a decrease in total ice mass of 82 28 km3 of ice per year, consistent with estimates from other techniques. Our uncertainty estimate is dominated by the effects of GRACE measurement errors and errors in our post glacial rebound (PG) correction. The main advantages of GRACE are that it is sensitive to the entire ice sheet, and that it provides mass estimates with only minimal use of supporting physical assumptions or ancillary data. Copyright 2005 by the American Geophysical Union. 1575 A user-friendly anisotropic flow law for ice-sheet modelling Gillet- Chaulet F., Gagliardini O., Meyssonnier J. et al. Journal of Glaciology 2005 51/172 (3-14) For accurate ice-sheet flow modelling, the anisotropic behaviour of ice must be taken fully into account. However, physically based micro-macro (-M) models for the behaviour of an anisotropic ice polycrystal are too complex to be implemented easily in large-scale ice-sheet flow models. An easy and efficient method to remedy this is presented. Polar ice is assumed to behave as a linearly viscous orthotropic material whose general flow law (GOLF) depends on six parameters, and its orthotropic fabric is described by an ‘orientation distribution function’ (ODF) depending on two parameters. A method to pass from the ODF to a discrete description of the fabric, and vice versa, is presented. Considering any available -M model, the parameters of the GOLF that fit the response obtained by running this -M model are calculated for any set of ODF parameters. It is thus possible to tabulate the GOLF over a grid in the space of the ODF parameters. This step is performed once and for all. Ice-sheet flow models need the general form of the GOLF to be implemented in the available code (once), then, during each individual run, to retrieve the GOLF parameters from the table by interpolation. As an application example, the GOLF is tabulated using three different -M models and used to derive the rheological properties of ice along the Greenland Icecore Project (GRIP) ice core. 1576 A distributed surface energy-balance model for complex topography and its application to Storglaci¨aren, Sweden Hock R. and Holmgren B. Journal of Glaciology 2005 51/172 (25-36) A grid-based surface energy-balance mass-balance model has been developed to simulate snow- and ice melt in mountainous regions with an hourly resolution. The model is applied to Storglaci¨aren, a valley glacier in Sweden, using a 30m resolution digital elevation model. Emphasis is directed towards computing the radiation components. These are modelled individually, considering the effects of slope angle, aspect and effective horizon. A new parameterization for snow albedo is suggested, modifying the albedo of the preceding hour as a function of time after snowfall, air temperature and cloudiness. The model is used to provide the meltwater input for discharge modelling and to assess the influence of the individual components on melt. Results are validated by means of observed melt rates, patterns of snow-line retreat and proglacial discharge. In general, simulations are in good agreement with observations. In particular, the diurnal and seasonal fluctuations of discharge are simulated remarkably well. 1577 Spatial and temporal evolution of rapid basal sliding on Bench Glacier, Alaska, USA Macgregor K.R., Riihimaki C.A. and Anderson R.S. Journal of Glaciology 2005 51/172 (49-63) We measured the surface velocity field during the summers of 1999 and 2000 on the 7 km long, 185 m thick Bench Glacier, Alaska, USA. In the spring of both years, a short-lived pulse of surface velocity, 2-4 times the annual mean velocity, propagated up-glacier from the terminus at a rate of 200-250 md-1 . Displacement attributable to rapid sliding is 5-10% of the annual surface motion, while the high-velocity event comprised 60-95% of annual basal motion. Sliding during the propagating speed-up event peaked at 6-14cmd-1 , with the highest rates in mid-glacier. Continuous horizontal and vertical GPS measurements at one stake showed divergence and then convergence of the ice surface with the bed as the velocity wave passed, with maximum surface uplift of 8-16 cm. High divergence rates coincided with high horizontal velocities, suggesting rapid sliding on the up-glacier side of bedrock steps. Initiation of the annual speed-up event occurred during the peak in englacial water storage, while the glacier was entirely snow-covered. Basal motion during the propagating speed-up event enlarges cavities and connections among them, driving a transition from a poorly connected hydrologic system to a well-connected linked-cavity system. Sliding is probably halted by the development of a conduit system. 1578 Borehole imagery of meteoric and marine ice layers in the Amery Ice Shelf, East Antarctica Craven M., Carsey F., Behar A. et al. Journal of Glaciology 2005 51/172 (75-84) A real-time video camera probe was deployed in a hot-water drilled borehole through the Amery Ice Shelf, East Antarctica, where a total ice thickness of 480 m included at least 200 m of basal marine ice. Down-looking and side-looking digital video footage showed a striking transition from white bubbly meteoric ice above to dark marine ice below, but the transition was neither microscopically sharp nor flat, indicating the uneven nature (at centimetre scale) of the ice-shelf base upstream where the marine ice first started to accrete. Marine ice features were imaged including platelet structures, cell inclusions, entrained particles, and the interface with sea water at the base. The cells are assumed to be entrained sea water, and were present throughout the lower 100-150 m of the marine ice column, becoming larger and more prevalent as the lower surface was approached until, near the base, they became channels large enough that the camera field of view could not contain them. Platelets in the marine ice at depth appeared to be as large as 1-2 cm in diameter. Particles were visible in the borehole meltwater; probably marine and mineral particles liberated by the drill, but their distribution varied with depth. 1579 Use of the ELA as a practical method of monitoring glacier response to climate in New Zealand’s Southern Alps Chinn T.J., Heydenrych C. and Salinger M.J. Journal of Glaciology 2005 51/172 (85-95) In lieu of direct glacier surface mass-balance measurements, equilibrium-line altitudes (ELAs) have been measured over a 28 year period at 50 selected glaciers distributed along the glacierized length of New Zealand’s Southern Alps. Analysis of the data shows that ELAs are a useful measurement of glacier response to annual climate fluctuations, although there is much variability in the degree of response between glaciers in any given year. Comparisons of individual glacier annual ELA with the mean for all annual ELAs of the Southern Alps show a large variation of individual glacier response, with coefficients of variation (r2 ) ranging from 0.53 to 0.90. The ELA data show detailed, but qualitative, annual mass-balance variations on both regional and individual glacier scales. The ELA record closely predicts glacier termini responses that follow after appropriate response time delays. The recorded variability in climate response for the Southern Alps suggests no single glacier is truly representative for detailed studies of glacier-climate relationships, and that a large number of ELA measurements may be as good an indicator of climate as a few mass-balance measurements. Given the appropriate mass-balance gradient, mass-balance values may be calculated for any of the monitored glaciers. 1580 Ice-elevation changes of Glaciar Chico, southern Patagonia, using ASTER DEMs, aerial photographs and GPS data Rivera A., Casassa G., Bamber J. and K¨aa¨ b A. Journal of Glaciology 2005 51/172 (105-112) Hielo Patag´onico Sur (HPS; southern Patagonia icefield) is the largest temperate ice mass at mid-latitudes in the Southern Hemisphere. With few exceptions, the glaciers in this region have been retreating during the last 50 years. Based on field data, vertical THE QUATERNARY aerial photographs and satellite images, ice-elevation changes since 1975 on Glaciar Chico, one of the main tongues of HPS, are presented. A maximum ice thinning of 5.4 0.55 ma-1 was observed at the glacier front between 1975 and 1997. Global positioning system (GPS) data were used in the accumulation area of the glacier to infer a thinning rate of 1.9 0.14ma-1 between 1998 and 2001. This thinning rate is three times higher than the snow accumulation rate estimated for that part of the glacier. A mean net glacier mass balance of -0.29 0.097 km3 w.e. a-1 was estimated between 1975 and 2001. Climate data suggest an increase in temperature and a reduction in precipitation during most of the 20th century in the vicinity of HPS. Although these climate changes are the primary explanation for the observed ice-elevation changes of the glacier, ice-dynamics effects are also believed to play an important role. 1581 Spatial and temporal variability of snow accumulation in East Antarctica from traverse data Frezzotti M., Pourchet M., Flora O. et al. Journal of Glaciology 2005 51/172 (113-124) Recent snow accumulation rate is a key quantity for ice-core and mass-balance studies. Several accumulation measurement methods (stake farm, fin core, snow-radar profiling, surface morphology, remote sensing) were used, compared and integrated at eight sites along a transect from Terra Nova Bay to Dome C, East Antarctica, to provide information about the spatial and temporal variability of snow accumulation. Thirty-nine cores were dated by identifying tritium/ marker levels (1965-66) and non-seasalt (nss) SO 24 spikes of the Tambora (Indonesia) volcanic event (1816) in order to provide information on temporal variability. Cores were linked by snow radar and global positioning system surveys to provide detailed information on spatial variability in snow accumulation. Stake-farm and ice-core accumulation rates are observed to differ significantly, but isochrones (snow radar) correlate well with ice-core derived accumulation. The accumulation/ablation pattern from stake measurements suggests that the annual local noise (metre scale) in snow accumulation can approach 2 years of ablation and more than four times the average annual accumulation, with no accumulation or ablation for a 5 year period in up to 40% of cases. The spatial variability of snow accumulation at the kilometre scale is one order of magnitude higher than temporal variability at the multi-decadal/secular scale. Stake measurements and firn cores at Dome C confirm an approximate 30% increase in accumulation over the last two centuries, with respect to the average over the last 5000 years. 1582 Dissipated work, stability and the internal flow structure of granular snow avalanches Bartelt P., Buser O. and Kern M. Journal of Glaciology 2005 51/172 (125-138) We derive work dissipation functional for granular snow avalanches flowing in simple shear. Our intent is to apply constructive theorems of non-equilibrium thermodynamics to the snow avalanche problem. Snow chute experiments show that a bilayer system consisting of a non-yielded flow plug overriding a sheared fluidized layer can be used to model avalanche flow. We show that for this type of constitutive behaviour the dissipation functionals are minimum at steady state with respect to variations in internal velocity; however, the functionals must be constrained by subsidiary mass-continuity integrals before the equivalence of momentum balance and minimal work dissipation can be established. Constitutive models that do not satisfy this equivalence are henceforth excluded from our consideration. Fluctuations in plug and slip velocity depend on the roughness of the flow surface and viscosity of the granular system. We speculate that this property explains the transition from flowing avalanches to powder avalanches. Because the temperature can safely be assumed constant, we demonstrate within the context of nonequilibrium thermodynamics that granular snow avalanches are irreversible, dissipative systems, minimizing - in space - entropy production. Furthermore, entropy production is linear both near and far from steady-state non-equilibrium because of the masscontinuity constraint. Finally, we derive thermodynamic forces and conjugate fluxes as well as expressing the corresponding phenomenological Onsager coefficients in terms of the constitutive parameters. 299 1583 Debris transport in a temperate valley glacier: Haut Glacier d’Arolla, Valais, Switzerland Goodsell B., Hambrey M.J. and Classer N.F. Journal of Glaciology 2005 51/172 (139-146) This paper considers the role of structural glaciology in debris entrainment, transport and deposition at Haut Glacier d’Arolla, a temperate valley glacier in Valais, Switzerland. Sedimentological descriptions and clast analysis have been used to identify relationships between ice structure and debris transport. Relationships identified are (1) debris associated with crevasse traces, (2) the folding of rockfall material incorporated within primary stratification to form medial moraines and (3) dirt cones and englacial debris layers associated with reactivated crevasse traces. A conceptual model is introduced to summarize the manner in which ice structures at Haut Glacier d’Arolla control entrainment and deposition of debris. 1584 Decadal-scale variations in ice flow along Whillans Ice Stream and its tributaries, West Antarctica Stearns L.A., Jezek K.C. and Van Der Veen C.J. Journal of Glaciology 2005 51/172 (147-157) We investigate velocity changes occurring along Whillans Ice Stream (WIS) by comparing velocities derived from repeat aerial photographs acquired in 1985-89 (average date of 1987) to interferometric satellite radar (InSAR) velocities collected in 1997. Three different analysis methods are applied to the velocity data. First, temporal and spatial changes in velocities are correlated to identifiable features (flowlines, shear margins, bed features) visible on the 1997 RADARSAT Antarctic Mapping Project mosaic. Second, we relate velocity gradients to stresses via the flow law and, along with surface topography and ice-thickness data, apply the force-budget technique to determine the relative importance of driving stress, side drag and basal drag over time. Finally, the mass balance of the main part of WIS is determined for 1987 and 1997. Our results are consistent with previous studies that show an overall deceleration resulting in downstream thickening of the ice stream (Whillans and others, 2001; Joughin and others, 2002). 1585 Instruments and Methods A non-destructive method for measuring the salinity and solid fraction of growing sea ice in situ Notz D., Wettlaufer J.S. and Worster M.G. Journal of Glaciology 2005 51/172 (159-166) We describe an instrument developed to make in situ measurements of salinity and solid-fraction profiles in growing sea ice. The vertical resolution of the measurements is up to a few millimeters, with a temporal resolution of up to fractions of a second. The technique is based on impedance measurements between platinum wires around which sea ice grows. Data obtained using this instrument in laboratory experiments are in good agreement with theoretical predictions. In a field test in the Arctic, the bulk salinity of growing sea ice has been measured in situ throughout the whole depth of the ice layer. The data are compared with bulk salinities obtained from ice cores, and confirm the general understanding that the bulk salinity in ice-core studies is significantly underestimated in the lower parts of the cores. The approach can also be used in other glaciological applications and for general studies of two-phase, two-component porous media. 1586 The retreat stages of Arve glacier between cluses bolt and chamonix ombilic during the lateglacial (Arve Valley, Haute-Savoie) (French) (Les stades de retrait du glacier de l’Arve entre le verrou de cluses et l’ombilic de chamonix au cours du tardiglaciaire (Vall´ee de l’Arve, Haute-Savoie)) Coutterand S. and Nicoud G. Quaternaire 2005 16/2 (85-94) This updated cartography of glacial deposits, especially the ablation moraines and the associated devices, such as kame terraces, enables us to suggest a paleogeography more complete of the various steps of the Tardiglaciaire deglaciation in the middle Arve Valley. The two main stages during the retreat, namely Magland and Le Fayet ones were subdivided into two subdivisions (Tour Noire and Pierre a` Voix), and four subdivisions, - Am´erands, Fayet d’en Haut, Fayet du Milieu and Fayet d’en Bas -, respectively. One age based on the exposur e method (Be10 ) performed on a crystalline erratic boulder of the Magland- 300 THE QUATERNARY Tour Noire stage-the most downstream from those studied in the Sallanches ombilic, yield 17540 50010 Be BP. On the basis of the various glacial equilibrium line values and on 10 Be ages, a correlation is suggested between our relative chronology and the Grisons scale (Switzerland). 1587 Laboratory study of erosion processes in snow avalanches Barbolini M., Biancardi A., Cappabianca F. et al. Cold Regions Science and Technology 2005 43/1-2 (1-9) In order to better understand the mechanics of erosive processes characteristic of snow avalanche flows, a series of laboratory experiments were carried out. In these experiments a mass of dry granular material was released in a channel with rectangular cross-section. A part of the channel was covered with an erodible layer. The experiments were recorded with a high-speed digital camera and the interaction between the flowing material and the erodible bed was studied using different colours for the two materials. The records allowed an extremely detailed high-frequency visualisation of the phenomenon. Observations of the erosion mechanisms as well as measurements of the erosion rates were performed. The results of the experiments were analysed and interpreted with respect to some theoretical erosion models from the literature. © 2005 Elsevier B.V. All rights reserved. 1588 Mathematical modeling of snow entrainment in avalanche motion Eglit M.E. and Demidov K.S. Cold Regions Science and Technology 2005 43/1-2 (10-23) The entrainment of snow plays an important role in snow avalanche dynamics. Various ways of incorporating the entrainment effect into avalanche mathematical models are discussed in this paper. The results of calculations using a variety of formulae for the entrainment rate that have been proposed for bed erosion by flows of various physical natures are presented. For various studied entrainment laws it is found that in motion at a steep slope the entrainment takes place in a frontal part of an avalanche. The motion of an avalanche depends mainly on the total depth of the entrainable snow layer and on the length of the entrainment zone, but only weakly on the form of the entrainment law. However the length of an entrainment zone depends on the values of the coefficients entering the entrainment law. © 2005 Elsevier B.V. All rights reserved. 1589 On size and shape effects in snow fracture toughness measurements Sigrist C., Schweizer J., Schindler H.- J. and Dual J. Cold Regions Science and Technology 2005 43/1-2 (24-35) Dry snow slab avalanche release is preceded by two fracture mechanical processes: shear failure of a weak layer or an interface within the snowpack, followed by tensile failure of the overlaying slab. For a slope stability analysis based on fracture mechanics, the fracture toughness of snow has to be known. The purpose of this work was to evaluate snow fracture toughness in mode I, to determine to what extent it is affected by the specimen size and shape and to search for adequate correction methods. Edgecracked beam-shaped snow specimens cut from homogeneous layers of naturally deposited snow were subjected to three-point bending and cantilever beam tests. To describe the size dependence an empirical size effect law and the FAD (failure assessment diagram) approach were explored. By comparing the three-point bending with the cantilever beam tests a shape dependence of the toughness was found. The fracture process zone was estimated to be in the order of at least one centimetre. Due to the large size of the fracture process zone a dependence of the toughness on the specimen size has to be expected, as it is typical for nonlinear, quasi-brittle materials. Experiments with four different specimen sizes clearly confirmed that toughness is size dependent, possibly up to the scale of a slab avalanche. Preliminary results suggest that the actual fracture toughness might be twice as large as the one determined experimentally. Therefore, size correction functions will be essential to transform toughness data of laboratory-scaled experiments to the scale relevant for snow slope stability models. © 2005 Elsevier B.V. All rights reserved. 1590 Two-dimensional mathematical and numerical model for the dynamics of granular avalanches De Toni S. and Scotton P. Cold Regions Science and Technology 2005 43/1-2 (36-48) This paper considers a model that reproduces the dynamics of snow avalanches from initiation to runout for a given terrain topography and given the volume, shape and position of the initial mass. According to the Savage-Hutter theory, the granular avalanche is treated as an incompressible cohesionless continuum, which satisfies a Mohr-Coulomb yield criterion and with a Coulomb-type friction law at the bottom. The internal and bottom friction angles, and , are the only rheological parameters to be set. The balance laws of mass and momentum are simplified imposing the "shallow water" assumption and then averaged along the vertical direction. The momentum balance along the direction normal to the bottom reduces to a hydrostatic distribution of pressure in a form which includes the centrifugal forces due to the curvature. The stress tensor is written in a coordinate system independent of the topography and related to the velocity vector. The numerical model is validated by laboratory experiments, performed at the Hydraulic Laboratory of the University of Trento, and by comparing the simulation results with data collected from the literature. The applicability of the model to natural snow avalanches is discussed with reference to observations on granular avalanches reported in the literature and to the surveys carried out at the Lavina Granda and Spini Valley avalanche sites in Trentino Province (Italy). © 2005 Elsevier B.V. All rights reserved. 1591 A low cost system for the estimation of concentration and velocity profiles in rapid dry granular flows Barbolini M., Biancardi A., Natale L. and Pagliardi M. Cold Regions Science and Technology 2005 43/1-2 (49-61) A series of laboratory experiments with granular material has been carried out at the Hydraulic and Environmental Engineering Department of the University of Pavia (Italy). The aim was to investigate the internal properties of fast moving dry granular flows, with particular attention paid to the measurements of concentration and velocity profiles. A low-cost acquisition system was built using a Pulnix digital camera and off-the-shelf components and integrating only open-source software around a GNU/Linux operating system. Different techniques for the measurements of velocity and concentration profiles have been proposed and tested. The flow regimes have been investigated and a distinction between "front", "body" and "tail" of the moving mass has been established in terms of the flow concentration. Additionally, a comparison with experimental results and theories found in the literature has been outlined. © 2005 Elsevier B.V. All rights reserved. 1592 Application of the snow cover model SNOWPACK to snow avalanche warning in Niseko, Japan Nishimura K., Baba E., Hirashima H. and Lehning M. Cold Regions Science and Technology 2005 43/1-2 (62-70) We describe the use of the snow cover model SNOWPACK for avalanche warning in Niseko, Japan. Input data was collected from a newly installed meteorological station at 800 m a.s.l. To verify the model output, snow pit observations were made almost everyday during the winter 2002-2003. Ten dry snow slab avalanches occurred during the observation period. Most of them were released after a heavy storm and had fracture depths of 40-60 cm. Pit observations revealed that the fracture layers in the snowpack consisted of either graupel or stellar precipitation particles without rime (70%) or faceted crystals (30%). Slab layers consisted of precipitation or decomposing and fragmented particles, which indicated that these avalanches occurred soon after the snow deposition. Snow profiles simulated with SNOWPACK roughly agreed with the observed profiles. The model reproduced faceted crystals on a crust that became the weak layer and caused the avalanches on 14-16 February 2003. In addition, air temperature, solar radiation, wind speed, and snow depth in the study area were estimated for grid points with 50 m spacing. This allowed to calculate for each grid point snow properties such as grain type and density as well as the snow stability index SI. The predictions agreed reasonably well with the field observations. © 2005 Elsevier B.V. All rights reserved. THE QUATERNARY 1593 High-speed photography of fractures in weak snowpack layers van Herwijnen A. and Jamieson B. Cold Regions Science and Technology 2005 43/1-2 (71-82) During the winters of 2002-2003 and 2003-2004, fractures in weak snowpack layers were recorded with a portable digital highspeed camera in the Columbia Mountains of British Columbia, Canada. Fractures were photographed at 250 frames per second in 21 compression tests, four rutschblock tests, three cantilever beam tests as well as on five skier-tested slopes. Theoretical slab avalanche release models generally assume propagation of a brittle shear fracture in an incompressible weak snowpack layer. However, displacement measurements of markers placed in the snow above the weak layer indicated that slope normal displacement (due to crushing of the weak layer) was directly caused by the fracture in the weak layer and independent of slope angle, whereas the slope parallel displacement following fracture was probably dependent on slope angle. Furthermore, displacement measurements from rows of markers placed in the snow above weak layers resulted in fracture speed measurements ranging from 17 to 26 m/s, in good agreement with the only other published fracture speed measurement known to the authors: 20 m/s. © 2005 Elsevier B.V. All rights reserved. 1594 Avalanche forecast using numerical weather prediction in Indian Himalaya Singh A., Srinivasan K. and Ganju A. Cold Regions Science and Technology 2005 43/1-2 (83-92) The integration of a nearest-neighbours method based avalanche forecast model with a mesoscale weather forecast model (MM5) has been attempted for avalanche forecasting in Indian Himalaya. The MM5 model simulates weather parameters up to day-4 over the entire western Himalaya. The paper describes the methodology of using MM5 model predictions and some empirical relations, to find the probability of avalanche occurrence up to day-4 at a spatial resolution of 5 km by applying the nearest-neighbours method. The nearest-neighbours model uses Euclidean weighted distance metric to find 10 nearest neighbours from the past data in terms of snow and weather parameters. Based on the avalanche occurrences associated with nearest-neighbours, an a priori probability of avalanche occurrence is derived. This approach has been tested for forecasting of avalanches in Chowkibal-Tangdhar road axis in Indian western Himalaya. © 2005 Elsevier B.V. All rights reserved. 1595 Improvement of a numerical snow drift model and field validation Durand Y., Guyomarc’h G., M´erindol L. and Corripio J.G. Cold Regions Science and Technology 2005 43/1-2 (93-103) For about 10 years, M´et´eo-France has developed and operated a real time operational suite aimed at snowpack simulation and avalanche risk forecasting: the numerical model chain SafranCrocus-Mepra (SCM). It presently includes only a crude formulation of snowdrift effects at large spatial scales (massif). This paper presents the improvements to a snow drift module suited to the SCM chain. The new version called SYTRON3 which aims at an improved simulation of snow drift effects at smaller spatial scales. It is coupled with the SCM environment, which provides hourly meteorological conditions and snow forcing. The main modifications concern the new parameterisation schemes, which are more realistic and more physically based. The increased number of vertical layers allows now to represent explicitly the three modes of movement during snow drift: creep, saltation and diffusion. The validation of this new version as well as comparisons with the previous version are performed at the Col du Lac Blanc test site (2700 m a.s.l., French Alps) by the use of digital photographs and field observations. © 2005 Elsevier B.V. All rights reserved. 1596 Avalanche activity in an extreme maritime climate: The application of classification trees for forecasting Hendrikx J., Owens I., Carran W. and Carran A. Cold Regions Science and Technology 2005 43/1-2 (104-116) Classification trees were trained to determine periods of significant avalanche activity in terms of an avalanche day, based on meteorological parameters for the Milford Road, Fiordland, New 301 Zealand. Using a 10 year data set of meteorological parameters and over 1800 individual avalanche occurrences from the Transit New Zealand Milford Road Avalanche Programme we have described and statistically explored this avalanche regime and the relationship between storm and avalanche activity in this extreme climatic region. The Milford Road is located in the south western corner of New Zealand and is dominated by a maritime climate delivering in excess of 8 m water equivalent per year in precipitation, while winter storms can deposit up to 2 m of snow in one storm. As the avalanche climate is dominated by direct action avalanching, the meteorological parameters up to a maximum of 72 h preceding a significant avalanche period were examined. Standard meteorological parameters including air temperature, air pressure, wind speed and direction, snow depth and precipitation were obtained from two automatic weather stations located in the starting zone and at road level. These parameters as well as two derived wind drift parameters were used as the variables for predicting the avalanche days. Two 10 fold cross validated classification trees were created, and suggested for use in forecasting. The classification tree with highest accuracy of 85% predicted avalanche days less well at 79%. An alternative tree using only wind speed and wind speed and precipitation combined in a temperature sensitive wind drift parameter resulted in a lower overall accuracy of 78%, but permitted a higher rate of correct prediction for avalanche days at 86%. The alternative, more conservative tree also reduced the number of false negative cases (observed as avalanche days, but predicted as non-avalanche days) from 31 to 20 at a cost of increasing the false positive or false alarm rate. © 2005 Elsevier B.V. All rights reserved. 1597 Geomorphological evidence for variations of the North Patagonian Icefield during the Holocene Glasser N.F., Jansson K.N., Harrison S. and Rivera A. Geomorphology 2005 71/3-4 (263-277) Elucidating the timing and extent of former glacier fluctuations is important because of the palaeoclimatic inferences that can be drawn from such studies. Here we present new geomorphological evidence of the patterns of glacier behaviour around the North Patagonian Icefield during the Holocene. Mapping is based on visual interpretation of Landsat 7 ETM+ and Terra ASTER satellite images, including the contemporary glaciers, areas of ice-scoured bedrock, trimlines, glacial lineations, terminal moraines, sandur and fluvial sediments, deltas and ice-contact deposits and alluvial fans. Recession of the icefield is marked by three distinct moraine sets. These moraine sets are interpreted as marking terminal positions related to the "Little Ice Age" and two preceding, but as yet undated, phases of Holocene glacier expansion. Large arcuate terminal moraines in front of three of the western glaciers are interpreted as composite features, reflecting topographic limits to glacier expansion, indicating that caution is required in the interpretation of previous 14 C dates obtained from these moraines. There are strong contrasts in the patterns of glacier behaviour between the east and west sides of the North Patagonian Icefield, which cannot be attributed simply to an east/west differential in the rates of change of atmospheric temperature and precipitation. We argue here that glacier response to first-order climate forcing is tempered by second-order controls introduced by regional-scale topographic effects, notably glacier drainage basin extent and area, topographic controls on glacier snout morphology and differences in terminal environment (calving/non-calving) during glacier recession. © 2005 Elsevier B.V. All rights reserved. 1598 Dating of Little Ice Age glacier fluctuations in the tropical Andes: Charquini glaciers, Bolivia, 16°S Rabatel A., Jomelli V., Naveau P. et al. Comptes Rendus Geoscience 2005 337/15 (1311-1322) Fluctuations of the Charquini glaciers (Cordillera Real, Bolivia) have been reconstructed for the Little Ice Age (LIA) from a set of 10 moraines extending below the present glacier termini. A lichenometric method using the Rhizocarpon geographicum was used to date the moraines and reconstruct the main glacier fluctuations over the period. The maximum glacier extent occurred in the second half of the 17th century, followed by nearly continuous retreat with three interruptions during the 18th and the 19th centuries, marked by stabilisation or minor advances. Results obtained in the Charquini area are first compared with other dating 302 SEDIMENTOLOGY performed in the Peruvian Cordillera Blanca and then with the fluctuations of documented glaciers in the Northern Hemisphere. Glacier fluctuations along the tropical Andes (Bolivia and Peru) were in phase during the LIA and the solar forcing appears to be important during the period of glacier advance. Compared with the Northern Hemisphere mid-latitudes, the major advance observed on these glaciers during the first half of the 19th century is not present in the tropical Andes. This discrepancy may be due to regional scale climate variations. © 2005 Acad´emie de sciences. Published by Elsevier SAS. All rights reserved. 1599 Ice-sheet extent of the Antarctic Peninsula region during the Last Glacial Maximum (LGM) - Insights from glacial geomorphology Heroy D.C. and Anderson J.B. Bulletin of the Geological Society of America 2005 117/11-12 (1497-1512) We present marine geological and geophysical data for the Antarctic Peninsula that call for a larger ice-sheet reconstruction during the Last Glacial Maximum (LGM) than suggested by previous studies. Such glacial reconstructions are important for quantifying post-LGM sea-level rise and providing boundary conditions for general circulation models. Megascale glacial lineations on the continental shelf surrounding Antarctica provide documentation for grounded ice that was streaming. Swath bathymetry data (NBP02-01) reveal lineations in each of the major glacial troughs, except for Smith Trough, which features grooves and bedrock drumlins (0.5-3 km spacing, 1:20 elongation ratios) on crystalline bedrock. We place the maximum extent of ice at the seaward limit of the lineations, at or near (<10 km landward of) the shelf break. The occurrence of line-sourced gullies at the mouth of each glacial trough (except Vega Trough, Weddell Sea) supports the interpretation of ice grounded at the shelf break. Megascale glacial lineations imaged in this study and other areas surrounding Antarctica (including the Ross Sea, Pine Island Bay) have a consistent morphology, with elongation ratios of >80:1 and spacings of 200-600 m (mode of 300 m). In contrast, lineations ("bundles"; Canals et al., 2000) in the Gerlache-Boyd Trough exhibit larger spacing (1-5 km), and the upstream portions (7 km) are carved directly into bedrock rather than till, as suggested by previously unpublished air gun (120 Hz) seismic data. These features have yet to be dated; however, they are believed to have been active during the LGM. Radiocarbon dates in glaciomarine sediments (foraminifera and organic matter) from seven glacial troughs indicate that megascale glacial lineations were formed during the LGM. Other geomorphic features, such as the grounding zone wedge in the northwestern Weddell Sea, formed when the ice sheet was retreating. The initial retreat of the grounded ice from the outer shelf occurred by 18,500 cal yr B.P. The inner shelf was mostly ice free by 13,000 cal yr B.P. This is significantly earlier than numerical models, which suggest Antarctic deglaciation began at 12,000 cal yr B.P. This also suggests the peninsula area contributed to global sea-level rise associated with meltwater pulse (MWP) 1a. © 2005 Geological Society of America. SEDIMENTOLOGY Sediments and sedimentary processes - physical properties 1600 Statistical and geostatistical features of streambed hydraulic conductivities in the Platte River, Nebraska Chen X. Environmental Geology 2005 48/6 (693-701) This paper presents streambed hydraulic conductivities of the Platte River from south-central to eastern Nebraska. The hydraulic conductivities were determined from river channels using permeameter tests. The vertical hydraulic conductivities (K v ) from seven test sites along this river in south-central Nebraska belong to one statistical population. Its mean value is 40.2 m/d. However, the vertical hydraulic conductivities along four transects of the Ashland test site in eastern Nebraska have lower mean values, are statistically different from the K v values in south-central Nebraska, and belong to two different populations with mean values of 20.7 and 9.1 m/d, respectively. Finer sediments carried from the Loup River and Elkhorn River watersheds to the eastern reach of the Platte River lowers the vertical hydraulic conductivity of the streambed. Correlation coefficients between water depth and K v values along a test transect indicates a positive correlation - a larger K v usually occurs in the part of channel with deeper water. Experimental variograms derived from the vertical hydraulic conductivities for several transects across the channels of the Platte River show periodicity of spatial correlation, which likely result from periodic variation of water depth across the channels. The sandy to gravelly streambed contains very local silt and clay layers; spatially continuous low-permeability streambed was not observed in the river channels. The horizontal hydraulic conductivities were larger than the vertical hydraulic conductivities for the same test locations. © Springer-Verlag 2005. Sediments and sedimentary processes - transport 1601 RRS Charles Darwin Cruise 126, 11 Mar-20 Mar 2001. Piston coring of debris flows and turbidites west and south of the Canary Islands Masson D.G. Cruise Report of the Southampton Oceanography Centre 2002 -/40 (15p) The major cruise objective was to obtain sediment cores at various locations to the west and southwest of the Canary Islands with the aims of: Sampling debris flow sediments in the Canary and Saharan debris flows Obtaining dateable sediments immediately above and below the debris flow sediments Sampling turbidite sediments associated with the debris flows Sampling sediments on either flank of a sediment wave west of La Palma In addition, it was planned to obtain seabed video footage, using the SHRIMP towed camera station, at several localities where downslope sediment transport was believed to be active at the present day, and undertake some test deployments of the SOC Scatterometer system. ©2003-2004 University of Southampton. 1602 Assessment of sediment yield of watersheds by reservoir survey and simulation modelling in Brazilian semiarid environment De Ara´ujo J.C. and Knight D.W. IAHS-AISH Publication 2005 -/299 (124-130) Reservoir survey is a reliable method for assessing sediment yield, which is a major environmental issue concerning impacts on water resources. The paper presents field surveys of one urban and six rural watersheds located in the Brazilian semiarid region, with a wide range of characteristics. Basin areas range from 3 to 1220 km2 ; reservoir capacity 0.5-126 Mm3 ; silting history 46-94 years; and hydrological regimes range from very dry "scrt˜ao" to mild mountain and coastal regions. Sediment yield assessment consisted of topo-bathymetric reservoir surveys; volume reduction computation; dry bulk density evaluation based on core samples; and trap efficiency estimation. Results showed per capita urban contribution to be 21 kg year-1 ; average sediment yield to be 426 t km-2 year -1 ; and reservoir-volume reduction at a rate of 2% per decade. The Hidrosed model was applied and field data were used for its validation. Hidrosed showed good agreement with field data, with Nash and Sutcliffe efficiency coefficient 0.81 for Maner SDR formulation. 1603 A theoretical exploration of catchment-scale sediment delivery Lu H., Moran C.J. and Sivapalan M. Water Resources Research 2005 41/9 (1-15) [1] This paper proposes a theoretical explanation of the variations of the sediment delivery ratio (SDR) versus catchment area relationships and the complex patterns in the behavior of sediment transfer processes at catchment scale. Taking into account the effects of erosion source types, deposition, and hydrological controls, we propose a simple conceptual model that consists of two linear stores arranged in series: a hillslope store that addresses transport to the nearest streams and a channel store that addresses sediment routing in the channel network. SEDIMENTOLOGY The model identifies four dimensionless scaling factors, which enable us to analyze a variety of effects on SDR estimation, including (1) interacting processes of erosion sources and deposition, (2) different temporal averaging windows, and (3) catchment runoff response. We show that the interactions between storm duration and hillslope/channel travel times are the major controls of peak-value-based sediment delivery and its spatial variations. The interplay between depositional timescales and the travel/residence times determines the spatial variations of total-volume-based SDR. In practical terms this parsimonious, minimal complexity model could provide a sound physical basis for diagnosing catchment to catchment variability of sediment transport if the proposed scaling factors can be quantified using climatic and catchment properties. Copyright 2005 by the American Geophysical Union. 1604 Estimating sediment budgets at the interface between rivers and estuaries with application to the Sacramento-San Joaquin River Delta Wright S.A. and Schoellhamer D.H. Water Resources Research 2005 41/9 (1-17) [1] Where rivers encounter estuaries, a transition zone develops where riverine and tidal processes both affect sediment transport processes. One such transition zone is the Sacramento-San Joaquin River Delta, a large, complex system where several rivers meet to form an estuary (San Francisco Bay). Herein we present the results of a detailed sediment budget for this river/estuary transitional system. The primary regional goal of the study was to measure sediment transport rates and pathways in the delta in support of ecosystem restoration efforts. In addition to achieving this regional goal, the study has produced general methods to collect, edit, and analyze (including error analysis) sediment transport data at the interface of rivers and estuaries. Estimating sediment budgets for these systems is difficult because of the mixed nature of riverine versus tidal transport processes, the different timescales of transport in fluvial and tidal environments, and the sheer complexity and size of systems such as the Sacramento-San Joaquin River Delta. Sediment budgets also require error estimates in order to assess whether differences in inflows and outflows, which could be small compared to overall fluxes, are indeed distinguishable from zero. Over the 4 year period of this study, water years 1999-2002, 6.6 0.9 Mt of sediment entered the delta and 2.2 0.7 Mt exited, resulting in 4.4 1.1 Mt (67 17%) of deposition. The estimated deposition rate corresponding to this mass of sediment compares favorably with measured inorganic sediment accumulation on vegetated wetlands in the delta. 1605 Transport of gravel and cobble on a mixed-sediment inner bank shoreline of a large inlet, Grays Harbor, Washington Osborne P.D. Marine Geology 2005 224/1-4 (145-156) Gravel and cobble transport measurements were obtained by particle tracing experiments from a mixed sand, gravel and cobble beach at the head of a crenulate-shaped shoreline, Half Moon Bay in Grays Harbor, Washington. The direct measurements and results provide insight regarding the differential transport of gravel and cobble sized material on mixed-sediment beaches. The results are of relevance to the development of both predictive formulae for coarse-grained sediment transport and guidance for practical gravel and cobble beach design. Net alongshore transport of gravel and cobble is generally several times greater than the net cross-shore transport at Half Moon Bay. Larger and smaller particles both move preferentially alongshore; however, smaller particles tend to move across-shore more than larger particles. Particle transport distance during a tidal cycle increases with particle size (or mass) up to a point, beyond which the particle transport rate begins to decrease with increasing size. The direct relationship between transport rate and particle size may reflect the selective entrainment and the rejection (or overpassing) of larger particles, which are more exposed to fluid forces on the beach surface than smaller particles, which are sheltered within the matrix of larger particles, as well as the higher susceptibility to burial of smaller particles. The decrease in transport rate for the largest sizes may reflect the limited competency of the fluid forces to transport larger and heavier particles under the observed conditions. The direct transport measurements are consistent with the overall particle size and shape distributions observed 303 on this crenulate-shaped inner bank beach whereby the larger and flatter particles have tended to outrun the smaller and more spherical particles in the downdrift direction. © 2005 Elsevier B.V. All rights reserved. 1606 Estimates of Australian dust flux into New Zealand: Quantifying the eastern Australian dust plume pathway using trace element calibrated 210 Pb as a monitor Marx S.K., Kamber B.S. and McGowan H.A. Earth and Planetary Science Letters 2005 239/3-4 (336-351) Weekly average atmospheric 210 Pb flux data collected between March 1989 and February 2001 are used to construct a record of Australian dust incursions onto the west coast, South Island, New Zealand. Dusts collected from New Zealand glaciers were found to contain a mixture of local New Zealand and long range Australian material, based on novel binary and tertiary mixing models of their ultra trace element chemistries. Trace element characteristics further allowed determination of the provenance of the long range dust component within Australia to better than 200 km resolution. 210 Pb analyses of these chemically characterised dust samples show that activity is related to the percentage of Australian dust in a linear fashion. However, 210 Pb activity of Australian dusts collected in New Zealand is orders of magnitude greater than that measured in the alluvial sediments of the provenance areas. Australian dusts collected in New Zealand are also highly enriched in 210 Pb compared to dusts collected in Australia. This shows that dust scavenges atmospheric 210 Pb which can therefore be used as an effective tracer of long range dust transport. Previously obtained average atmospheric 210 Pb flux data can thus be converted into the first record of long range Australian dust flux in New Zealand. Results show that the average atmospheric concentration of Australian dust in New Zealand is 5.3 g m-3 . There is a clear seasonality with the highest concentrations occurring in autumn-winter, preceding Australia’s major dust storm season, which occurs in winterspring. We propose that while meteorological factors control the occurrence of major dust storms, the availability of sediment in source areas is a major control on Australian dust flux in New Zealand. Dust flux is greatest after seasonal river flows when transport of extremely fine grained dust occurs. This is followed by transport of larger particles in the more spectacular winter-spring dust storms. Our results provide information on the characteristics and seasonality of dust transport in the Australian region, which had previously been difficult to quantify by other methods (e.g., satellite imagery). Results also attest to the effectiveness of 210 Pb as a tracer in this region. © 2005 Elsevier B.V. All rights reserved. 1607 Process-based model linking pocket gopher (Thomomys bottae) activity to sediment transport and soil thickness Yoo K., Amundson R., Heimsath A.M. and Dietrich W.E. Geology 2005 33/11 (917-920) Burrowing organisms assist in shaping earth surfaces and are simultaneously affected by the environment they inhabit; however, a conceptual framework is not yet available to describe this feedback. We introduce a model that connects the population density of soil-burrowing animals to sediment transport via energy. The model, combined with available data from California hillslopes where soil erosion is driven by pocket gophers (Thomomys bottae), suggests that a gopher annually expends 9 kJ of energy, or 1% of reported burrowing energy expenditure, in generating sediment transport. The model is used to evaluate the case that gophers prefer to populate thicker soils. The results suggest that this behavior may drastically dampen the spatial and temporal variations of soil thickness and gopher populations, implying that burrowing organisms may create landscapes distinct from those affected by abiotic process. © 2005 Geological Society of America. 1608 Prograde Rayleigh wave particle motion Tanimoto T. and Rivera L. Geophysical Journal International 2005 162/2 (399-405) Fundamental mode Rayleigh waves generally show retrograde particle motion at the surface of the Earth. If there exists a thick sedimentary layer, however, reversal of the sign of vertical eigenfunction occurs near the surface, resulting in prograde 304 SEDIMENTOLOGY Rayleigh-wave particle motion at the surface. We show that, for structures similar to those found in the Los Angeles basin (with thickness up to 8 km), surface prograde motion may occur within the frequency band 0.05-0.3 Hz. Although it has been suggested that the effect of gravity on waves in unconsolidated surface layer may be important, partitioning of energy between the elatic and gravitational energy shows that the gravitational energy is less than 1 per cent and thus is not important. The phenomenon is caused by elastic effects, mainly caused by extremely slow shallow seismic velocities. Observation of prograde elliptical particle motion may be difficult, however, because particle motion is largely horizontal and high microseismic noise exists in the same frequency band. © 2005 RAS. 1609 Sediment suspension dynamics and a new criterion for the maintenance of turbulent suspensions Leeder M.R., Gray T.E. and Alexander J. Sedimentology 2005 52/4 (683-691) The vertical component of the turbulent flow acceleration term, @ (u i u j - is used to determine the net positive vertical force that may support a suspended sediment load. A dimensionless criterion, A, is proposed for the maintenance of suspension, defined as the ratio of the maximum vertical turbulent stress to immersed weight of the suspended load above a unit bed area. In order that a suspension be maintained: A=(v 2 -)max /m( -/ )g1 where v’ is instantaneous vertical turbulent velocity, and are solid and fluid densities, respectively and m is the suspended load dry mass. The A criterion is dynamic, being a ratio of stresses and is analogous in this respect to Shields dimensionless stress criterion, , for the initiation of bedload motion. The new criterion is successful in predicting the maintenance of steady-state suspended sediment transport in open channel shear flow and deposition from non-uniform particulate density flows of wall jet type. © 2005 International Association of Sedimentologists. 1610 Sand grain threshold, in relation to bed ‘stress history’: An experimental study Paphitis D. and Collins M.B. Sedimentology 2005 52/4 (827-838) Besides particle size, density and shape, the erodibility of a sediment bed depends also upon the exposure to prethreshold velocities in the overlying flow. Such flow effectively rearranges the grains (at and below the bed surface), causing them to become more resistant to subsequent erosion. The effects of the ‘stress history’, leading up to the critical condition for sediment movement, are investigated for unidirectional flows generated in a recirculating laboratory flume. The sediment beds investigated consisted of cohesionless quartz sand grains, with mean grain diameters of 0-194 mm (fine sand), 0-387 mm (medium sand) and 0-774 mm (coarse sand), with narrow particle-size distributions. The critical (threshold) shear velocity (target value) for the three beds was established, within 2-5 min of increasing the flow from zero velocity. The subsequent experiments were performed under prethreshold velocities at 70% (for 5, 10, 20, 40 and 80 min exposure duration), 80% (for 5, 10, 20, 40 and 80 min exposure duration), 90 and 95% (for 5, 10, 20, 40, 80 and 120 min exposure duration) of the target value. Following exposure to these different prethreshold conditions, the flow was increased then to reach actual critical conditions, within a period of 2-5 min. The critical condition for the initiation of sediment movement was established using visual observation (supplemented by video recordings), according to the Yalin criterion. The results show that if the exposure duration to prethreshold velocities remains constant, then the critical shear velocity increases with increasing prethreshold velocity. Likewise, if the prethreshold velocity remains constant, then the critical shear velocity increases with increasing exposure duration. In some circumstances, the critical shear velocity was found to increase by as much as 27%. An empirical formula is proposed to account for the exposure correction to be applied to the critical shear velocities of sandsized sediment beds; this is prior to their inclusion into bedload transport formulae, for an improved prediction of the magnitude and nature of transport. © 2005 International Association of Sedimentologists. 1611 Bedload path length and point bar development in gravel-bed river models Pyrce R.S. and Ashmore P.E. Sedimentology 2005 52/4 (839-857) Low-sinuosity meandering gravel-bed flume experiments were employed to investigate spatial patterns of deposition, which point to patterns of channel development related to the pool and bar morphology. At channel-forming discharges, fluorescent bedload tracers indicate that deposition is typically focused around the point bar apex, downstream of the apex (contributing to downstream bar migration), and at the bar head/riffle surface. Seven flume experimental runs illustrate a sequence of point bar development related to the spatial patterns of tracer deposition, and the related path length distribution. At early stages of bar formation, transport is from the scour zone across the point bar head to the bar apex and bar margin downstream of the apex. As the point bar develops, bedload transport across the bar decreases, as transport along the channel thalweg increases and sediment is deposited along the bar margin. Deposition cells appear to move from downstream to upstream of the bar apex as this sequence of bar formation progresses. At low (non-channel-forming) discharges, transport occurs to the bar head/riffle surface with very little material being transported to the apex region or point bar interior. The implication is that there is an inherent connection between the loci of particle deposition and point bar formation, largely controlled by the morphology of the channel. © 2005 International Association of Sedimentologists. 1612 Wind forces and related saltation transport Leenders J.K., van Boxel J.H. and Sterk G. Geomorphology 2005 71/3-4 (357-372) The effect of several wind characteristics on sand transport was studied in three experiments in north Burkina Faso, West Africa. The first experiment is used to analyse the relation between wind speed and shear stress fluctuations across height. The second experiment is used to study the relation of these wind characteristics with saltation transport for fourteen convective storms, registered during the rainy seasons of 2002 and 2003. The effect of sampling time is studied for two of these convective storms. The third experiment relates the turbulent structures of four convective storms to saltation transport. Wind speed measurements were undertaken with two sonic anemometers and sediment transport was measured by two saltiphones. The sampling frequency was either 8 or 16 Hz. The sonic frame of reference was rotated according to a triple rotation. Horizontal fluctuations showed a (fairly) good correlation with height because the wind speed at both sensors was affected by the same vortices. The correlation coefficients ranged from 0.42 (when the distance between the sensors was 1.75 m) to 0.92 (when the distance was 0.25 m). The instantaneous Reynolds’ stress had the weakest correlation (correlation coefficient of 0.05 at 1.75 m between the sensors and 0.56 at 0.25 m between the sensors), because the momentum at 2 m above the soil surface is transported by different eddies than those close to the ground. This also explains the fairly good correlation coefficients between the horizontal components of the wind and saltation compared to the poor correlations between instantaneous Reynolds’ stress and saltation. An increase in sampling time did not have much impact on these correlation coefficients up to sampling periods of about 30 s. However, this sampling interval would be too coarse to describe the vertical wind component adequately. The classification of the moments of shear stress into the turbulent structures, sweeps, ejections, inward and outward interactions, showed that the mean saltation flux is higher at sweeps and outward interactions than at ejections and inward interactions. Also, saltation occurred more often during sweeps and outward interactions than during ejections and inward interactions. © 2005 Elsevier B.V. All rights reserved. 1613 Processes of soft-sediment clast formation in the intertidal zone Knight J. Sedimentary Geology 2005 181/3-4 (207-214) Muddy soft-sediment clasts found on the sandy beach at Formby Point, north-west England, are formed by wave erosion of late Holocene intertidal sediments that are exposed during summertime ridge and runnel development. Break-up processes of the intertidal sediments are strongly controlled by pre-existing bedding and surface desiccation cracks. Erosion of the intertidal sediments and formation of soft-sediment clasts contributes to the provision of fines into this dominantly sandy environment, but loss of the archaeologically significant Holocene intertidal SEDIMENTOLOGY sediments is a potentially important management issue along this coast. © 2005 Elsevier B.V. All rights reserved. Sediments and sedimentary processes - deposition 1614 Sediment and organic carbon focusing in the Shelikof Strait, Alaska Rember R. and Trefry J. Marine Geology 2005 224/1-4 (83-101) Profiles of excess 210 Pb and 137 Cs in sediment cores were used to determine sediment accumulation rates in Outer Cook Inlet and the Shelikof Strait, Alaska. In Outer Cook Inlet and the northern Shelikof Strait, sediment accumulation rates averaged 0.16 cm yr-1 and ranged from 0.10 to 0.21 cm yr-1 . In contrast, sediment accumulation rates were > 4 times higher in the central and southern Shelikof Strait where the average was 0.68 cm yr-1 with a range of 0.46 to 0.94 cm yr -1 . In addition to higher rates of sedimentation, higher activities of excess 210 Pb and higher levels of silt + clay, total organic carbon, Pb and Mn also were found in surface sediments from the central and southern Shelikof Strait relative to Outer Cook Inlet and the northern Shelikof Strait. These trends are directly related to the progressive sorting and focusing of sediments along the transport pathway from Cook Inlet to the Shelikof Strait. The flux of excess 210 Pb and organic carbon to the sediments increased by > 2- and 4.8-fold, respectively, from Outer Cook Inlet and the northern Shelikof Strait to the central and southern Shelikof Strait. Based on 13 C values for surface sediments, the amount of carbon derived from marine sources increased from 30% in Outer Cook Inlet and the northern Shelikof Strait to 60% in the central and southern Shelikof Strait. The good correlation between the accumulation rate of sediment organic carbon and excess 210 Pb fluxes (r = 0.93) suggests that scavenging of excess 210 Pb by organic carbon is an important process in this region. Modern sediment budgets for Outer Cook Inlet and the Shelikof Strait indicate that > 70% of the total sediment accumulation of 61 106 tons yr-1 is deposited in the central and southern Shelikof Strait. These sediment budgets are in good agreement with the calculated value of 70 106 tons yr-1 of riverine and erosional sediment transported into Outer Cook Inlet and the Shelikof Strait. Collectively, the data support focusing of finegrained sediments and organic carbon to the central and southern Shelikof Strait. © 2005 Elsevier B.V. All rights reserved. 1615 Millennial-scale depositional cycles from the Holocene of the Po Plain, Italy Amorosi A., Centineo M.C., Colalongo M.L. and Fiorini F. Marine Geology 2005 222-223/1-4 (7-18) The Holocene depositional history of southeastern Po Plain on time scales of 103 yr is reconstructed, based upon integrated sedimentological and micropalaeontological analyses of nine continuously-cored boreholes, about 40 m deep. Major palaeoenvironmental changes include the rapid landward migration of a barrier-estuary-lagoon system during the Early-Middle Holocene (transgressive systems tract-TST), followed by extensive delta progradation in the last 6000 yr (highstand systems tract-HST). Detailed facies analysis of cores combined with the identification of 12 microfossils (benthic foraminifer and ostracod) associations allow an ultra-high-resolution sequence-stratigraphic framework to be reconstructed. Particularly, eight small-scale, high-frequency cycles, about 3-5 m thick and spanning intervals of time of about 1000 yr, can be physically traced throughout the study area. Interpretation of these cycles, which are invariably bounded by sharp flooding surfaces and generally show internal shallowing-upward trends (parasequences), indicates that relative sea-level changes during the Holocene were episodic and punctuated by rapid phases of sea-level rise, followed by periods of stillstand (or decreasing sea-level rise). From seaward to landward locations, parasequence boundaries document beachbarrier migration, bay-head delta abandonment and increasing accommodation in the coastal plain. The ensuing phases of sealevel stillstands resulted in the progressive filling of the newly formed accommodation space, through beach progradation, extensive mud deposition in behind-barrier lagoonal (estuarine) and 305 marsh deposits, and aggradation in bay-head delta systems at the head of estuaries. Eustacy appears to be the major controlling factor of the retrogradational stacking pattern of parasequences within the TST. By contrast, a complex interplay of eustacy, sediment supply and subsidence, with an increasing influence of autocyclic mechanisms, such as channel avulsion and delta lobe abandonment, controlled facies architecture within the HST. The maximum flooding surface cannot be assumed to be synchronous, its timing being strongly dependent upon local variations in sediment influx and subsidence. This study shows that the micropalaeontologic characterization of mud-prone (coastal plain and estuarine) successions in terms of water depth and salinity can lead to very accurate sequence-stratigraphic interpretations, allowing identification of parasequence boundaries that may not be detected by conventional stratigraphic approach. © 2005 Elsevier B.V. All rights reserved. 1616 The modern Po Delta system: Lobe switching and asymmetric prodelta growth Correggiari A., Cattaneo A. and Trincardi F. Marine Geology 2005 222-223/1-4 (49-74) The modern Po Delta system, comprising five main delta lobes, has been investigated by integrating VHR seismic surveys, recorded offshore from water depths as shallow as 5 m to the toe of the prodelta in about 30 m, with accurate historical cartography extending back several centuries. Previous studies give sedimentological and geochronological information from precisely positioned sediment cores. This combined historical and stratigraphic reconstruction of the modern Po prodelta allows volumetric reconstructions indicating an average sediment load of 9.4 106 t yr-1 for Po di Pila and Po di Goro-Gnocca lobes. This estimate is remarkably consistent with the total sediment load of 11.5 106 t yr-1 available for parts of the last century from a gauge station at the apex of the delta plain (in Pontelagoscuro). These integrated stratigraphic studies allow to explain the key characters of the Po delta system: a) the marked asymmetry of the whole delta-prodelta system reflecting prevailing sediment dispersal to the south of each individual delta outlet; b) the shore-parallel overlapping of successive prodelta lobes fed by distinct river outlets of ever changing relative importance; c) the delta outlets being artificially forced in a fixed position so that natural avulsion is prevented and delta lobes undergo headland retreat leaving a marked erosion on the prodelta; d) the presence of prodelta lobes showing widespread "cut-and-fill" features (ranging from 100 to 300 m and depths up to 4-5 m filled with massive silt to very fine sand) offshore of short-lived very active distributary channels (e.g.: Po di Tolle lobe) and suggesting that, in some particular interval, short-lived episodes of submarine erosion are induced by catastrophic increases in river discharge (of natural origin or induced by human maintenance). The seismic stratigraphy of the modern Po Delta documents that markedly distinct prodelta architectures form when a newly activated lobe is located updrift (north, in this case) or downdrift (south) of the one that is retreating: in the first case the abandoned lobe becomes sheltered by the new, rapidly advancing, one; in the opposite case the retreating lobe is updrift and a substantial portion of the sediment is cannibalized and transported to the new lobe, downdrift. © 2005 Elsevier B.V. All rights reserved. 1617 Distributary channels and their impact on sediment dispersal Syvitski J.P.M., Kettner A.J., Correggiari A. and Nelson B.W. Marine Geology 2005 222-223/1-4 (75-94) A global analysis of world deltas, with details from a natural and an anthropogenic-influenced delta, demonstrates how distributary channels control the flux of sediment into the coastal ocean. The study addresses the range in the number of distributary channels across world deltas using remote sensing techniques. A power law relationship is found between the number of distributary channels and the length of river and, separately, the delta gradient. These relationships hold for all types of deltas whether controlled or strongly influenced by waves, river discharge, tides or ice (permafrost or sea-ice). Nature-controlled deltas, such as the Klinaklini delta, have distributary channels that act as overflow conduits that become active during flooding events. Anthropogenic-controlled deltas, like the Po delta, have distributary channels that are controlled for flood mitigation or 306 SEDIMENTOLOGY low flow maintenance. Anthropogenic influences greatly impact the natural rate of delta progradation through changes in sediment supply, controlling the position of distributary channels, and impacting subsidence from gas and groundwater extraction. Even with flood controls, the Po delta traps 16% of the sediment load in its channels that are becoming super-elevated at rates of 4 to 10 cm/yr, with respect to the delta plain. A new model is formulated and shown to predict accurately the sediment flux through each channel, along with their hydraulic properties. Deltas with high numbers of distributary channels produce hypopycnal plumes with reduced transport capacity. As a result, sediment diffuses out of the multi-channel deltas as a buoyantly driven plume, rather than as a momentum driven jet. © 2005 Elsevier B.V. All rights reserved. 1618 The use of 7 Be to identify event and seasonal sedimentation near the Po River delta, Adriatic Sea Palinkas C.M., Nittrouer C.A., Wheatcroft R.A. and Langone L. Marine Geology 2005 222-223/1-4 (95-112) In October 2000, a major flood event of the Po River occurred. The resulting seabed deposit was initially sampled in December 2000, and most sites were reoccupied on subsequent cruises over a 3-yr period. Using the maximum penetration depth of the shortlived radioisotope 7 Be (half-life 53.3 d), the flood deposit was found to be up to 15 cm thick. Individual depocenters of thick strata were located immediately adjacent to the distributaries at the river mouth in relatively shallow water (< 30 m). These flood deposit thicknesses are minimum estimates because the depth of 234 Th (half-life 24.1 d) exceeds that of 7 Be in physically stratified flood sediment, indicating that the first sediment deposited during the flood event likely originated from the river channel. 30-55% of the estimated sediment load delivered to the shelf during the flood event can be accounted for using 7 Be penetration depths. Seasonal deposition also can be quantified using 7 Be, after removing the effects of biological mixing. Seasonal deposition rates are a maximum of 6 cm yr-1 near the Pila distributary, decreasing to 2 cm yr-1 in the southern portions of the dispersal system. © 2005 Elsevier B.V. All rights reserved. 1619 Fine-sediment mass balance in the western Adriatic continental shelf over a century time scale Frignani M., Langone L., Ravaioli M. et al. Marine Geology 2005 222-223/1-4 (113-133) To obtain a quantitative estimate of the sediment accumulating on the muddy belt extending along the western Adriatic continental shelf, a budget was calculated based on the mass accumulation rates measured from more than one hundred activity-depth profiles of 210 Pb. 137 Cs depth-distributions were used, when possible, to support 210 Pb results. 210 Pb profiles show quasi-monotonic declines in the foreset region of the central Adriatic clinoform. In the prodelta of the rivers Po and Isonzo, 210 Pb profiles are characterized by intervals of low and uniform activity, which are thought to be produced by flood deposition. Since the north Adriatic is shallow and occasionally affected by storms from Bora wind, sediments are not in steady-state and their accumulation is the net result of recurring deposition, resuspension and winnowing events. In the western Adriatic, mass accumulation rates range between 0.04 and 6.6 g cm-2 yr-1 . Peak values were recorded in the Po and Isonzo prodeltas and along a narrow belt between Pescara and the Gargano promontory. Furthermore, the latter depocentre is located immediately seaward of the offlap break (40-50 m water depth) and parallels that of the most recent sigmoid of the HST. The integration of mass accumulation rates throughout the mud wedge of the north and central Adriatic gave a value of 42.0 Tg yr-1 of sediment accumulating along the Italian coast. The balance between sediment accumulation and riverine sediment supply (46.6 Tg yr-1 ) suggests an export of 4.6 Tg yr-1 to the south Adriatic basin and/or the Mediterranean Sea. The along-shore sediment transport is very effective and, in particular, 16.2 Tg yr-1 of sedimentary material (35% of the riverine supply) is transferred from north to central Adriatic, through the Ancona section. © 2005 Elsevier B.V. All rights reserved. 1620 Po River plume on the Adriatic continental shelf: Dispersion and sedimentation of dissolved and suspended matter during different river discharge rates Boldrin A., Langone L., Miserocchi S. et al. Marine Geology 2005 222-223/1-4 (135-158) Suspended matter and dissolved nutrients were studied in the prodelta of the Po River (northern Adriatic Sea) immediately after one of the greatest floods of the last century, which occurred in October 2000, and in four successive seasonal conditions. Hydrology, total suspended matter (TSM), particulate organic carbon (POC) and particulate nitrogen (PN) content, organic carbon stable isotopes ( 13 CPOC ), particle grain size spectra, phytoplankton, and dissolved inorganic nutrients (i.e., nitrate, nitrite, ammonium, phosphate, and silicate) were measured in different discharge conditions to describe processes occurring in the Po River delta. The main effect of high river discharge was a large volume of low salinity water at the surface that extended over the entire study area. The concentration of most sampled variables decreased along a dilution gradient from the Po River distributaries’ mouths to the offshore. For TSM at the surface, riverine input and dilution were the main factors affecting its distribution. At the bottom, however, increased TSM in the nearshore was due to rapid sinking of suspended matter at the river mouth, while resuspension and advection dominated the transport of near bottom sediments offshore at 15-20 m depth. In the offshore where resuspension was active, an increase in ammonium and decrease in oxygen supported the presence of regeneration processes occurring at the bottom. During the October 2000 flood event, high nutrient concentrations promoted new production, triggering an algal bloom in the southern region of the study area. The origin of particulate organic carbon in the river delta was then estimated from a mixing model based on 13 CPOC values and carbon : nitrogen (C / N) molar ratios, and as the contribution of three distinct sources of organic carbon were determined (i.e., marine, riverine, and terrestrial). The riverine end-member accounted for 50% of the surface POC and generally decreased towards the offshore. The terrestrial carbon contribution was generally the least abundant (20-28% at the surface and at depth, respectively) and exhibited peak values (30-40%) during the October 2000 flood. Last, the marine contribution was the most abundant at the bottom (40%) and generally increased offshore. During the October 2000 flood, the fluvial contribution of particulate organic carbon, that is the terrestrial and riverine fractions, represented approximately 80% of the total particulate organic carbon in the Po River delta. © 2005 Elsevier B.V. All rights reserved. 1621 Shallow gas and flood deposition on the Po Delta Orange D., Garca- Garca A., Lorenson T. et al. Marine Geology 2005 222-223/1-4 (159-177) Sediment cores acquired on the Po delta, northwestern Adriatic Sea, in water depths of 10 to 25 m yielded anomalous concentrations of methane up to 41,300 ppm. Of the 19 unique sites analyzed 5 sites (9 cores) had more than 90 ppm of CH4 and of those, 3 sites (4 cores) had more than 13,800 ppm methane. Compositional and isotopic analyses of the gas support a bacterial origin. Anomalous methane concentrations were found in kasten, gravity, and box cores; where more than one core type was acquired at a single location, all cores contained anomalous methane. Despite the regional high productivity in the Adriatic, all of the highest gas concentrations were found in the region associated with the thickest accumulation of recent flood deposits off the most active channel of the Po delta (Po di Pila). Cores acquired in this region contain primary sedimentary structures that indicate rapid burial of thick (> 10 cm) flood deposits and a relative lack of bioturbation down to the base of the flood layer. We propose that in the Po delta, flood deposits deliver significant amounts of terrigenous organic matter that can be rapidly buried on the prodelta, effectively removing this organic matter from aerobic oxidation and biological uptake, and leading to the potential for methanogenesis with burial. In areas unaffected by this high flux of organic matter and rapid/thick flood deposition, or in between flood events, our data indicate that the conditions for methanogenesis and gas accumulation have not been met. We suggest that in these areas, the physical and biological reworking of the surficial sediment between flood events may effectively oxidize and mineralize organic matter (derived from both marine SEDIMENTOLOGY and terrestrial sources) and limit bacterial methanogenesis in the subsurface. © 2005 Elsevier B.V. All rights reserved. 1622 Numerical modeling of hyperpycnal plume Khan S.M., Imran J., Bradford S. and Syvitski J. Marine Geology 2005 222-223/1-4 (193-211) When the density of sediment laden river water exceeds that of the ambient ocean water, the river plunges to the ocean floor and generates a hyperpycnal plume. Hyperpycnal plumes can travel significant distances beyond the continental shelf and may be sustained for hours to weeks. There are several Apennine Rivers in Italy that are likely to develop hyperpycnal discharges on the Western Adriatic shelf. Among them, River Tronto is a moderately ‘dirty’ river capable of producing 64 hyperpycnal flow events (lasting 6 h) during a 100 year period. Numerical simulations of hyperpycnal events have been conducted for the Adriatic shelf near the mouth of River Tronto using a twodimensional depth-integrated finite volume model to study the spreading of the plume and its interaction with the alongshore current. Simulation results indicate that the alongshore current has great impact on the spreading and deposition pattern of the hyperpycnal flow. Sedimentary deposits generated from a series of simulated hyperpycnal flow events have developed undulating bed forms. © 2005 Elsevier B.V. All rights reserved. 1623 Pleistocene "muddy" forced-regression deposits on the Adriatic shelf: A comparison with prodelta deposits of the late Holocene highstand mud wedge Ridente D. and Trincardi F. Marine Geology 2005 222-223/1-4 (213-233) The upper Pleistocene-Holocene stratigraphy of the Adriatic margin consists of a succession of depositional sequences separated by shelf-wide unconformities. The most recent of these depositional sequences encompasses the last ca. 25 kyr, and consists of lowstand, transgressive and highstand units formed, respectively, during the Last Glacial Maximum lowstand, the subsequent sea level rise and the modern highstand. Older deposits are grouped into four depositional sequences, each recording ca. 100 kyr glacio-eustatic cycles during an interval between ca. 450 and 25 kyr BP. Each of these Pleistocene sequences is composed dominantly by muddy progradational units deposited during prolonged phases of sea level fall; therefore, these sequences represent a unique example of well-preserved muddy forced-regression deposits. Detailed seismic-stratigraphic analyses show that forced-regression deposits composing the four sequences are not directly connected to nearshore and/or fluvio-deltaic environments. In contrast, typical forced-regression deposits defined in outcrop and reported in the literature consist of sand-rich, nearshore/deltaic facies preserved as patchy remnants of ancient shorelines. We suggest that muddy forced-regression deposits on the Adriatic shelf represent the offshore counterpart of shoreface deposits recognised in outcrop as the product of typical forced regressions. Interestingly, muddy forced-regression deposits on the Adriatic shelf bear clear similarities with the late Holocene highstand mud wedge, suggesting a common depositional mechanism through lateral advection of fine-grained sediment. In this view, subaqueous progradation of muddy deposits occurs below storm wave base, with a subaqueous roll-over point that, during proceeding sea level fall, likely positioned at decreasing distance from the time-equivalent shoreline. © 2005 Elsevier B.V. All rights reserved. 1624 Evolution of the Rhˆone delta plain in the Holocene Vella C., Fleury T.- J., Raccasi G. et al. Marine Geology 2005 222-223/1-4 (235-265) The delta plain of the Rhone shows many sandy beach ridges cropping out at the surface. We propose here a radiocarbon chronology for the accumulation of the sedimentary bodies and an interpretation of the morphology of the mouth lobes that they form. Morphologies of the lobes depend on four principal factors: (1) the variation of the relative sea level, which constitutes the morphogenic base level, (2) the fluvial input (volume of water discharge and sedimentary input, number and position of the mouths), (3) marine dynamics (volume and direction of the longshore drift, dominant wave direction) (4) the accommodation space created by the rise of relative sea level, along with the paleobathymetry onto which the lobe will prograde imme- 307 diately in front of the delta and at sea. Our conclusions are: the main Holocene paleo-delta lobes of Ulmet and Saint Ferr´eol were contemporaneous, being deposited from 4000 to 2000 yr BP. However, the fluvial style of their downstream channel (meandering for Ulmet channel and linear for Saint-Ferr´eol) and the lobe morphologies of both channels are contrasted: rounded in the case of Ulmet and elongated for Saint-Ferr´eol. The role of the accommodation space is confirmed by two recent drillholes traversing the entire Holocene succession, which reveal a prior stage of sedimentary filling in the case of the Saint-Ferr´eol lobe, thus limiting the accommodation space and favouring a rapid and pointed progradation of this lobe. The decoupling between hydrological activity and progradation of lobe indicates the complexity of mechanisms in the large catchment basin of Rhˆone. However, the high rate of progradation of Saint-Ferr´eol lobe after 2900 BP is probably a consequence of the increase of human activity after this date. The variation of relative sea level remains an important factor controlling the evolution of the Rhone delta after 6000 BP. The local (?) stabilization of the relative sea level between 4585 BP and 3520 BP played an important role in the triggering of coastal progradation (SaintFerr´eol lobe, eastern margin Rhˆone delta). © 2005 Elsevier B.V. All rights reserved. 1625 High resolution stratigraphy and evolution of the Rhˆone delta plain during Postglacial time, from subsurface drilling data bank Boyer J., Duvail C., Le Strat P. et al. Marine Geology 2005 222-223/1-4 (267-298) This study is based upon a large set of core drilling data (lithology and well logs) of the Rhˆone delta plain extracted from the French geological survey (BRGM) databank. The main goals are to set up a sequence stratigraphy model of the postglacial sedimentary bodies of the Rhˆone delta plain and to evaluate the relative importance and influence of the main controlling factors and processes (subsidence, eustasy, sediment yield, climate, anthropic influence) that led to their formation. First, a detailed study (60 drill holes with tenth meters spacing) was performed on a restricted area (Saint Ferr´eol lobe, 1.5 km2 ). Correlation between well logs data and lithological data allows to identify the main sediment lithofacies and key surfaces, and to set up a detailed stratigraphic framework. Postglacial deposits are subdivided into a lower member of coastal plain and backbarrier deposits and an upper member of marine deposits (coastal barrier environments). Following, the analysis of 160 wells distributed on the whole delta plain depicts the large scale architecture of postglacial deposits. In the upper delta plain, fluviatile coastal plain and palustral deposits prevail. In the lower delta plain, the deposits are made of a lower part of coastal plain deposits organized into four units (T1-T4) stacked in a retrograding pattern. This lower member is truncated by an erosional surface progressively deepening seaward. Above, an upper member of marine deposits thickening seaward and coarsening upward is organized into five units (P1-P5) arranged in a prograding pattern. The core drilling data have been correlated with high resolution seismic data on the adjacent shelf and are interpreted in sequence stratigraphy terms. The retrogradational units (T1T4), with coastal plain deposits, are correlative of shelf units and constitute together trangressive parasequences deposited during phases of slowing down of postglacial sea level rise. The upper marine units (P1-P5), arranged in a prograding pattern, represent parasequences of the Highstand Systems Tract which have prograded since the period of reduced rate of sea level rise at the end of the Holocene. During this period, the evolution of the sedimentary Rhˆone system was controlled by major changes of the hydrologic regime. Periods of increased sediment discharge, aggradation of the floodplain and progradation of the coastline are correlated with the development of the deltaic lobes of the Rhˆone d’Ulmet (unit P3) and of the Rhˆone du Bras de Fer (unit P4). Unit P5 correlates with adjacent prograding shelf unit that developed seaward of the present Rhˆone river mouth. Comparison of sea level history between the Eastern part of the Rhˆone delta plain and the rocky coast to the east of Marseille suggests that tecto-subsident movements account for part of the changes in relative sea-level. Moreover, the truncation of transgressive and progradation surfaces, the unevenness of the MFS, the dilatation 308 SEDIMENTOLOGY of sedimentary record and deformations of key surfaces are also in favor of differential subsidence. 1626 Seismic stratigraphy of the Deglacial deposits of the Rhˆone prodelta and of the adjacent shelf Labaune C., Jouet G., Bern´e S. et al. Marine Geology 2005 222-223/1-4 (299-311) In order to achieve a synthesis of the stratigraphic organization of the Deglacial deposits of the inner/middle shelf in front of the Rhˆone delta plain, we merged high resolution (Mini-sparker and Sparker), and very high resolution (chirp and mud-penetrator) seismic data into a single seismic database. Thus, the merged seismic database improves the lateral correlation between eastern and western parts, separated by the Rhˆone Incised Valley deposits. As a result the interpretation of seismic units in relation to local and global environmental changes was refined. The Deglacial deposits rest on a basal erosional discontinuity capping a complex of Pleistocene prograding wedges. The identified units make up Transgressive and Highstand Systems Tracts, and are bounded by flooding surfaces. The main flooding surfaces are (1) the transgressive surface (D200) which forms the lower boundary of the Deglacial deposits and (2) the maximum flooding surface which forms the boundary between the Transgressive and Highstand Systems Tracts. Regarding the data set the study area is divided into three parts depending on the stacking pattern and main control factors. In the western area the units present an aggradational stacking pattern and the rate of sediment supply and dynamic conditions seems coupled with glacio-eustacy role on sedimentary units building and evolution. In the central area the units present an overall backstepping pattern mainly controlled by glacio-eustacy. In the eastern area the units present an aggradational stacking pattern and both the glacio-eustacy and rate of sediment supply have an important role. The lower parasequence of the Transgressive Systems Tract (U200) is due to the reworking of W¨urmian terraces. Above, the parasequence U300 is a transgressive body formed during a rapid sea-level rise. The two upper parasequences are interpreted as ancestral coastal systems with a backstepping pattern. The first coastal system (U400) is due to a decrease in the rate of sea-level rise that occurred during the Younger Dryas. The second coastal system (U500) may be due to a similar event or to an increased rate of sediment supply during a constant sea-level rise. Finally the Highstand Systems Tract is composed of three units: (i) unit U601, located to the West and interpreted as a subaqueous delta, (ii, iii) units U600 and U610, located to the East and interpreted as prograding deltaic lobes. 1627 Small rivers contribution to the Quaternary evolution of a Mediterranean littoral system: The western gulf of Lion, France Tesson M., Labaune C. and Gensous B. Marine Geology 2005 222-223/1-4 (313-334) Along the Mediterranean coasts and the Atlantic French coast, former and actual research programs focused on major river systems, estuaries and deltas, characterized by a last Glacial relative sea level lowstand and incision and a well developed sedimentary incised valley infilling deposited during the following sea level rise and highstand. This paper presents the preliminary results of a program focused on a particular area of the Gulf of Lion coast with a thin sedimentary cover over the substratum and only minor rivers with non-apparent and important sedimentary contribution during the Late Quaternary. The results show that in this area the best Pliocene to Actual sedimentary record is preserved. The paper rests on the analysis of an extensive database of recent high resolution and very high resolution seismic reflection lines and previously published core data. Seismic data show that a major complex of paleovalleys connected with the Orb, Aude and Agly rivers is preserved on the inner shelf and adjacent coastal plain. On the inner shelf, the separated incised valleys merged in a unique broad and shoreparallel incision dipping southward. At the southward extremity, the incision turns eastward and seaward. The basal surface of this incision extends seawards under six to seven Late Quaternary depositional sequences preserved on the mid and outer shelf. The infilling of the complex of paleovalleys is characterized by aggrading deposits attributed to periods of relative sea level rise (transgressive systems tracts), organized into several subunits bounded by internal discontinuities locally deeply incising. The discontinuities are amalgamated surfaces, including successive sequence boundaries (indicative of phases of relative sea level falls) merged with transgressive surfaces (indistinct tidal and wave ravinement surfaces). The subunits are the part of Late Quaternary depositional sequences preserved in estuarine environments. They are the lateral equivalents of landward fluvial terraces and seaward coastal and prodelta¨ıc deposits on the shelf. Using borehole dataset, the underlying and eroded deposits below the basal unconformity are correlated with Pliocene deposits outcropping landward in the hinterland. The top of the incised valleys complex is capped by the last Glacial lowstand surface of erosion (18 ky B.P.) reworked by the postglacial transgressive surface (TS), dissociated near the shoreline into a tidal and a wave ravinement surfaces. Above the TS, the very high resolution (VHR) seismic data in the lagoons, the tidal channels and cores, reveal in details the stratigraphic architecture of the deposits. At the base, a small wedge constitutes the postglacial transgressive systems tract (TST) locally thinning in the areas distant of the sediment point sources. The TST is capped by a flat surface of wave reworking (maximum flooding surface or mfs) prolongating under the Leucate lagoon and merging offshore at the seafloor. Boreholes and VHR seismic lines trough the coastal barrier and in the lagoon show that the shoreline probably migrated far landward at the end of the transgression. When the rate of sea level rise decreased strongly, the shoreline migrated seaward and prograding and aggrading sandy material, with landward muddy lateral equivalent facies, deposited early highstand systems tract (HST) above the MFS. Offshore, fine material deposited as a sigmoidal blanket of mud originating in part from the north-east and Rhˆone river under oceanic circulation (equivalent to a subaqueous prodelta). Subsequently, the modern beach barrier built up by wave reworking of the early HST. This new study of the western part of the Gulf of Lion inner shelf and littoral illustrates an incised valley complex and thus presents the best preserved example of the sedimentary record of the effects of the relative sea level changes during the Pliocene to Actual period. For the first time, the land to sea transition is preserved and the Late Quaternary depositional sequences are in a great part observed. The last post Glacial deposits present a simplified but very different organisation compared to a record front of the adjacent Rhˆone river. Consequently a synthesis is now possible. 1628 Formation of the Aude, Orb and Herault prodeltas and their characterisation using physicochemical and sedimentological parameters Pauc H. Marine Geology 2005 222-223/1-4 (335-343) The formation of Mediterranean prodeltas depends on microtidal estuarine dynamics. The study of the Aude estuary and others shows the usual presence of a salt wedge which induces the formation of two turbidity maxima created by two different processes [Pauc, H. 1997. Fluvio-marine interface in a microtidal mediterranean estuarine environment. The nephelo¨ıd layer supply problem. Journ. Rech. Oc´eanogr. 22 (3), 83-90]. The first process is a loss of charge due to the annulment of the current momentum, driving sedimentation of the silt-size material. The second process is flocculation, which results in deposition of fine sediment. The end results of the combination of these two processes is a sedimentary sequence with two distinct sediment units: silt below and clay minerals above. Granulometrical and mineralogical analysis of the sediment body enables the zone of sedimentation of each type of material to be determined, and hence the style of sedimentation to be inferred. Illite, quartz and dolomite are of detrital origin and accumulate close to the river mouths; while smectite is deposited by both dynamical and flocculation processes, and accumulating over the surface of the prodelta and also seaward by some 30-40 m depth. Calcite is of biogenic origin, and is found further offshore, associated with muddy sediments only. © 2005 Elsevier B.V. All rights reserved. 1629 Early muddy deposits along the Gulf of Lions shoreline: A key for a better understanding of land-to-sea transfer of sediments and associated pollutant fluxes Roussiez V., Aloisi J.- C., Monaco A. and Ludwig W. Marine Geology 2005 222-223/1-4 (345-358) Large quantities of sediment introduced by rivers especially during flood events lead to the formation of prodeltaic structures characterized by fine-grained deposits in the proximal area of the SEDIMENTOLOGY shelf. According to their mean grain size, it is largely admitted in the literature that these deposits mainly stand below the storm wave base. In the Gulf of Lions (NW Mediterranean), however, our data show that these muddy sediments also exist above the storm wave limit, in the uppermost unit of the Holocene prism. The purpose of this work is therefore to draw a detailed sedimentological and geochemical portrait of these units, and to discuss the processes involved in the sedimentation and remobilization of these sediments. Our results show that the fine particles accumulate earlier in the inner-shelf in front of the nearby rivers, in association with the chemical elements which are commonly associated with this grain size fraction (e.g. organic carbon, radionuclides, and heavy metals). This accumulation probably mainly occurs during storm and flood events. The early deposits are then exposed to resuspension events and can actively participate to the distribution of fine-grained sediment in the entire margin by advective transfers via the benthic nepheloid layer. These fine-grained nearshore prodeltas are a common feature of the Mediterranean deltaic systems and mark the frontal processes that occur at the continent/sea interface of non-tidal seas. Our results especially point out the potential use of heavy metals as markers of the tracking of riverine sediments, which is naturally an important condition when evaluating the ultimate fate of landderived pollutants in the marine realm. But also more fundamental studies on the understanding of sedimentological processes and reconstruction of margin stratigraphies should consider these deposits as functional units for the distribution of platform sediments. © 2005 Elsevier B.V. All rights reserved. 1630 Development of the Kura delta, Azerbaijan; a record of Holocene Caspian sea-level changes Hoogendoorn R.M., Boels J.F., Kroonenberg S.B. et al. Marine Geology 2005 222-223/1-4 (359-380) Late Holocene deposits of the Kura delta indicate an alternating dominance of deltaic and shallow marine environments. These major environment shifts are controlled by the high frequency sea-level changes of the Caspian Sea. The level of the Caspian Sea, now at 27 m below Global Sea Level (GSL), changes at rates of up to a hundred times as fast as global sea level, allowing observation of sedimentary processes on a decadal scale that would take millennia in an oceanic environment. The modern Kura delta is a river-dominated delta with some wave action along its north-eastern flank, and without tidal influence. Morphological and hydrological changes have been monitored for over 150 years, continuing up to the present day using remote sensing imagery. Offshore sparker survey data, onshore and offshore corings, biostratigraphical analysis and radiometric dating enable a reconstruction of the Holocene Kura delta. Four phases of delta progradation alternating with erosional transgressive surfaces have been identified, representing just as many cycles of sea-level fall and rise. The first cycle is represented by lowstand deposits truncated by a transgressive surface (TS1) at ca. 80 m below GSL. TS1 is overlain by several metres of laminated clays and silts, deposited during a Late Holocene forced regression (H1). These deposits are truncated by the prominent reflector (TS2), corresponding to the Derbent lowstand around 1500 yr BP and subsequent transgression. This transgressive surface is overlain by prograding shallowing upwards deposits, H2, in turn truncated by a third transgressive surface (TS3), correlated with a lowstand of ca. 32 m below GSL. The last phase, H3, comprises an onshore progradational unit followed by an aggradational unit with an offshore veneer of clays and silts, corresponding to the formation of the modern Kura delta that started at the beginning of the 19th century. © 2005 Elsevier B.V. All rights reserved. 1631 Internal structure and evolution of the Late Quaternary sequence in a shallow embayment: The Amvrakikos Gulf, NW Greece Kapsimalis V., Pavlakis P., Poulos S.E. et al. Marine Geology 2005 222-223/1-4 (399-418) The Late Quaternary stratigraphic pattern of the Amvrakikos Gulf in the eastern Mediterranean has been studied on the basis of the analysis of high-resolution seismic profiles and short sediment cores. Lowstand, transgressive and highstand systems tracts have been identified that are configured in a major depositional sequence of a fifth-order sea level cycle. During the last glaciation, when the sea level was lowered by 55 m relative 309 to its present position (ca. 50 ka BP), the Amvrakikos Gulf was probably emerged, giving rise to: (a) subaerial erosion and fluvial incision in the western shallow part of the Gulf; and (b) development of a paleo-lake in the eastern deepest domain. Until the early phase of the post-glacial transgression (ca. 11-50 ka BP), a paleo-river, characterized by a dense network of V-shaped valleys, was draining the western part of the Gulf and flowing into the Ionian Sea. In the isolated eastern part, lowstand lacustrine deposits (deltaic and prodeltaic units) accumulated within the paleo-lake. At the latter stage of the last post-glacial transgression (ca. 11 ka BP), seawater entered the Gulf and the transgressive systems tract was deposited, consisting of incised-channel fills, beach-shoreface deposits and delta/prodelta wedges. Buried terraces have been identified also within this transgressive tract that reveal a step-like sea level rise. Since ca. 6 ka BP, when the sea level reached its present-day position, a distal prodeltaic unit has been deposited and overlain by prograding deltaic wedges. The spatial distribution of these wedges provides evidence of a continuous shifting of the river mouths during Holocene. The recent sedimentation patterns are related to the terrigenous inputs primarily from the Arachthos River, located in the northeastern part of the Gulf, and secondarily from the Louros River, located in the northwestern part. © 2005 Elsevier B.V. All rights reserved. 1632 Stratigraphic signature of the Vesuvius 79 AD event off the Sarno prodelta system, Naples Bay Sacchi M., Insinga D., Milia A. et al. Marine Geology 2005 222-223/1-4 (443-469) Sedimentological and chemical analysis of gravity core samples, along with the interpretation of very high resolution, single channel seismic reflection profiles acquired off the Sarno prodelta system (southeastern Naples Bay), document the sedimentary facies and seismic stratigraphic signature of the tephra deposit erupted by Vesuvius during the plinian eruption of 79 AD. The 79 AD pyroclastic deposits sampled off the Sarno prodelta system revealed significantly different characters with respect to both the subaerial succession documented from the type sections of Pompeii, Herculaneum and Oplontis and the more distal pyroclastic fallout deposits that were recovered from the outer continental shelf off the northern Salerno Bay. This was likely to be expected as, in proximal subaqueous settings, both primary deposition and reworking of tephra are known to be influenced by the hydrodynamics of the water itself (induced by the pyroclastic currents entering the sea) as well as by the early instability of pyroclastic bedforms due to the exceptionally high sediment yield during volcanic eruption. According to the data illustrated and discussed in this study, we suggest that the 79 AD tephra deposit sampled off the Sarno prodelta is likely to be the result of a number of syn-eruptive genetically-related depositional and/or erosional mechanisms associated with (1) anomalous waves (tsunami) and currents generated by the entrance of pyroclastic flows and surges into the sea; (2) subaqueous density flows evolved from the impact of hot pyroclastic currents into the seawater; (3) failure of water-logged, cohesionless pumice deposits, due to instability of pyroclastic bedforms rapidly accumulating on the seafloor. Seismic interpretation revealed that the Upper Holocene sequence off the Sarno prodelta system is affected by extensive creep involving the whole post-79 AD succession. Deformation due to creep is documented by slumping of semi-consolidated strata over a basal surface represented by the lithologic discontinuity between the base of the 79 AD tephra deposits and the underlying hemipelagite. Seismic data also suggest that gravitational instability of this area has been induced, or enhanced, by significant volcanotectonic deformation and local uplift of the seafloor that ostensibly predated the eruptive event. The results of this research may be relevant to studies of other eruption events in close proximity to coastlines in terms of wave- and/or current-generated sedimentary features as a possible explanation of unusual subaqueous facies architecture. © 2005 Elsevier B.V. All rights reserved. 1633 Mediterranean river systems of Andalusia, southern Spain, and associated deltas: A source to sink approach Liquete C., Arnau P., Canals M. and Colas S. Marine Geology 2005 222-223/1-4 (471-495) The northern shores of the semi-isolated Mediterranean Sea with 310 SEDIMENTOLOGY its low tidal range and a relatively voluminous fluvial supply of sediments constitute an ideal delta forming environment. In this paper, we examine the present-day and multi-decadal behaviour of 26 river systems from Andalusia, southern Spain, forming deltas in the Alboran Sea, the westernmost basin in the Mediterranean Sea. Eastern, Central and Western Andalusian watersheds have been defined based on geomorphological, climatological and hydrological characteristics. A comprehensive data set has been compiled, including satellite images, aerial photographs, a digital elevation model, thematic maps, time series of precipitation, temperature and water discharge, and the damming history of individual river basins. This data set has been used to analyse basin morphology and hydrology, and anthropogenic impact. Several modelling approaches have been applied to obtain the water budget and mean annual sediment yield of 12 of the 26 studied river systems. In addition, the periodicities of water discharge events and their possible link with North Atlantic Oscillation (NAO) fluctuations have been also studied. A decreasing trend has been observed in most water discharge time series during the last decades, which has been attributed to natural factors. Although it could have been expected that the diminution of water discharge may have caused a reduction in sediment load, calculated sediment discharge time series do not show any significant tendency. In general, sediment yield shows an opposite relationship with basin area. A comparative analysis of Spanish Mediterranean deltas indicates that in terms of sediment transport Andalusian river systems are quite efficient despite the small size of their catchments. Repetitive flood events and the consequent suspension plumes off river mouths play a major role in the development of deltaic and prodeltaic bodies. Nowadays, 42% of the study area is regulated, although to date the effect of dam building is hardly noticeable on river mouths. © 2005 Elsevier B.V. All rights reserved. 1634 Characterization of deltaic sediment bodies based on in situ CPT/CPTU profiles: A case study on the Llobregat delta plain, Barcelona, Spain Lafuerza S., Canals M., Casamor J.L. and Devincenzi J.M. Marine Geology 2005 222-223/1-4 (497-510) This article describes a preliminary study on the Llobregat delta, Spain, which includes the construction of a 3D model from cone penetration tests (CPT) and piezocone tests (CPTU) in order to establish the architectural stacking pattern of deltaic sediment bodies. The sediment facies identified from boreholes have been characterized by using their mechanical behaviour and have been used to identify the depositional sequence of the Llobregat delta. Within the general architectural frame, flood plain silts and silty sands, crevasse sands, fluvial channel sands, sand ridges, delta front silts and clays, and prodelta silts and clays have been characterized as a function of cone tip resistance (qc ) and sleeve friction (fs ). From the sediment facies characterization, a depositional sequence constituted by three systems tracts is proposed. The sequence is divided into: a lowstand systems tract (LST) represented by fluvial gravels, a transgressive systems tract (TST) constituted by a fining-upward sequence with a thin sand sheet below silts and clays, and the highstand systems tract (HST) represented by three prograding wedges displaying coarseningupward sequences. We emphasize the simplicity, speed, high spatial resolution and low cost of CPT/CPTU grids as a new tool enabling us to reconstruct the three-dimensional structure of deltaic environments for sedimentological and stratigraphical purposes. © 2005 Elsevier B.V. All rights reserved. 1635 Origin of depositional sequences from T´emara caves (Morocco) based on heavy minerals and quartz grains exoscopy (French) (Origine du remplissage s´edimentaire des grottes de T´emara (Maroc) d’apr`es l’´etude des min´eraux lourds et l’´etude exoscopique des grains de quartz) Niftah S., Debenath A. and Miskovsky J.- C. Quaternaire 2005 16/2 (73-83) Quaternary deposits of the areas of Rabat and Casablanca (Morocco) have been intensively investigated. We focus here on depositional sequences from the caves of El Mnasra (Casino), Ouled Bouchikha (Les Contrebandiers) and El Harhoura II in the area of T´emara. The sequences are correlated with isotopic stages 3 and 2. Exoscopic study under ESEM (Environmental Scan- ning Electron Microscope) of quartz grains selected throughout the different sequences has helped to describe sediment transport processes, Sediments originating from various areas of the Moroccan Meseta and Middle Atlas, were carried by wind and river transport, and then deposited along the coastal continental shelf They followed there a complex evolutionary process before completing their transport which ended in the T´emara caves. 1636 Sedimentological study of sediment from an hypersaline system of oriental Tunisia in recent quaternary: Mok´ nine sebkha (French) (Etude du remplissage s´edimentaire d’un syst`eme hypersalin de la Tunisie orientale au cours du quaternaire r´ecent: La sebkha de Moknine) Chairi R. Quaternaire 2005 16/2 (107-117) Results from a detailed sedimentological study of sediments from Moknine sebkha indicate two different deposit episodes. The first is characterized by an abundance of mud and organic matter which is good preserved in clay level. The second episode is qualified by the progradation of clay and organic matter to the centre. This evolution is controlled by two important factors such as dissymetry of basin topography and the abundance of rivers on the West. In the past, the sebkha is widened than actual. The abundance of clay in the base of the sequence at the periphery and in intermediate zone gives evidence. Clay level is rich on smectite which is more deposit in the center of the sebkha and contains high quantity of organic matter. Organic matter fraction is dominated by autochthonous material indicated by high values of hydrogen index and n-alkanes centred on nC18 and nC22. 1637 Sedimentation model for the quaternary intramontane Bhimtal-Naukuchiatal Lake deposits, Nainital, India Shukla U.K. and Bora D.S. Journal of Asian Earth Sciences 2005 25/6 (837-848) The Bhimtal-Naukuchiatal Lake was created due to blocking of the valley by a huge debris flow along a narrow outlet at about 40 ka BP. The lake basin was filled intermittently due to fluvio-lacustrine and colluvial processes that deposited a thick sequence of interbedded mud and gravel. In the basin fill sequence five major lithofacies, most of them divisible into subfacies, have been identified and assigned to specific depositional environments. The coarsening upward (CU) mud-silt cycles represent sedimentation in a lake setting. The clasts-and mud-supported gravels consists of fining upward (FU) and CU sequences, respectively, indicating deposition by channel processes and debris flows. Having basin wide extent, the pedogenic mottled, clayey silt unit represents an important tectonic event when the lake was temporarily drained and sediments were sub-aerially exposed. Fluctuating arid-semiarid to humid climatic conditions and repeated tectonic activity may have governed the mode of sedimentation and ultimately the basin fill history. © 2004 Elsevier Ltd. All rights reserved. 1638 History of sedimentary infilling and faulting in Subic Bay, Philippines revealed in high-resolution seismic reflection profiles Cabato Ma.E.J.A., Rodolfo K.S. and Siringan F.P. Journal of Asian Earth Sciences 2005 25/6 (849-858) Subic Bay sediments and faults identified in seismic-reflection profiles were dated using sea-level curves. The oldest sedimentary packages are marine sediments subaerially exposed and eroded 20 ka. Fluvio-marine to wholly marine sediments were deposited during the ensuing transgression, and prograding units were deposited during stillstands or minor sea-level falls. Faults within the bay have three age ranges. The oldest set cuts through the pre- 18 O Stage 2 rock units, >18 ka; a second disrupts 10.211.3 ka sediments; and the youngest, which cut the uppermost sedimentary package, show that movements occurred about every 2 ky, most recently about 3 ka. Northwest-southeast faults that parallel onshore structures associated with Paleogene emplacement of the Zambales Ophiolite Complex to the west and north likely represent rejuvenated tectonism. The northern coastline and north-south-trending axial bay islands appear related to a lineament that dissects Mt Pinatubo farther northeast. A breach in the caldera of Mt Natib is the most likely source of a presumed pyroclastic deposit in the eastern bay that is associated with sediments about 11.3-18 ka, indicating that a Natib eruption SEDIMENTOLOGY occurred much more recently than previously documented for this volcano. © 2004 Elsevier Ltd. All rights reserved. 1639 Bar and dune development during a freshet: Fraser River Estuary, British Columbia, Canada Villard P.V. and Church M. Sedimentology 2005 52/4 (737-756) Bi-weekly multi-track sonar surveys collected along a 2-km reach of the estuarine South Arm of the Fraser River, British Columbia, Canada, during seasonal high flows document the initiation, development and interaction of dune and bar morphologies. Bedforms of several scales developed in well-delineated fields. Bedforms that appear to fit accepted equilibrium depth-scaling developed in the main channel during rising discharge when there was little local aggradation. During the rising stage, a bar also formed along the tidal shelf of the channel, migrated downstream and expanded into the main channel. Dunes that formed along the bar crest, a region of rapid deposition, lagged flow conditions and were larger than expected based on depth-scaling relations. The larger dunes developed simultaneously, although bar growth lagged dune development and was initially partially obscured by the more rapidly developing dune field. It appears that rapid deposition enhances dune development along the channel tidal shelf to dimensions larger than would be expected by simple depth-scaling rules. Smaller dunes that fit equilibrium depthscaling relations re-established themselves throughout the study area during falling discharge when there was again little or no aggradation. Bed-material transport rates estimated from the migration rates of the large dunes suggest that, at high flows, the dunes transport the majority of the material found within the bar. © 2005 International Association of Sedimentologists. 1640 Quantification of the dry aeolian deposition of dust on horizontal surfaces: An experimental comparison of theory and measurements Goossens D. Sedimentology 2005 52/4 (859-873) Eight techniques to quantify the deposition of aeolian dust on horizontal surfaces were tested in a wind tunnel. The tests included three theoretical techniques and five measurement techniques. The theoretical techniques investigated were: the gradient technique, the inferential technique without grain-shape correction, and the inferential technique corrected for grain shape. The measuring techniques included the following surrogate surfaces: a water surface, a glass surface, a metal surface, a vertical array of metal plates, and an inverted frisbee filled with glass marbles. The efficiency of the techniques was investigated for the sediment as a whole (all grain sizes together) as well as for a large number of grain sizes extending from 1 to 104 m. The surrogate surfaces showed more or less comparable catch efficiencies, although the water surface nearly always caught the highest quantities of dust and the marble-filled frisbee and the vertical array of metal plates the lowest quantities of dust. The dust fluxes calculated by theoretical methods were markedly different from those obtained by direct measurements. The fluxes calculated by the inferential technique approximated those of the direct measurements only for grain sizes between 30 and 40 m. For smaller and coarser grains, deviations from the measured fluxes were high. The gradient method, in its turn, provided extremely low calculated fluxes for grains in all size classes investigated. The latter technique was not considered very reliable for the dust used in the tests. © 2005 International Association of Sedimentologists. 1641 Effects of calculation procedure and sampling site on trap method estimates of sediment resuspension in a shallow lake Horppila J. and Nurminen L. Sedimentology 2005 52/4 (903-913) Resuspension estimates given by two different trap methods in a shallow lake were compared. The sensitivity of the methods to errors in estimates of gross sedimentation and organic fraction of trapped material was explored. The methods were label method, in which resuspension is estimated by determining the organic fraction of surface sediment, suspended seston and trapped material, and SPIM/SPM method, where the relationship between settling particulate inorganic matter (SPIM) and total settling particulate matter (SPM) is used. During the whole 111 day study period, according to the label method, at a sheltered station 1949 g m-2 dry weight of sediment was resuspended, whereas SPIM/SPM gave an estimate of 1815 g m-2 . The difference in 311 the estimates was probably due to mineralization loss of organic material in the traps during the two week exposure periods. Sensitivity analysis showed that of the two methods, the label method was more sensitive to variations in the organic content of trapped material. At a wind-exposed station, the total amounts of resuspended matter given by the label method and by the SPIM/SPM method were 4966 g m-2 and 4971 g m-2 , respectively. Due to wind effects, escape of trapped material took place, which caused underestimation of gross sedimentation and compensated the effects of mineralization loss to diminish the difference between the methods. Of the two methods, the SPIM/SPM method seems thus more suitable for lakes, where bacterial activity is high. If cyanobacterial blooms take place, the label method is probably more reliable, providing that the exposure time of sediment traps is kept adequately short. © 2005 International Association of Sedimentologists. 1642 Recent evolution of a Mediterranean deltaic coastal zone: Human impacts on the Inner Thermaikos Gulf, New Aegean Sea Kapsimalis V., Poulos S.E., Karageorgis A.P. et al. Journal of the Geological Society 2005 162/6 (897-908) The Inner Thermaikos Gulf is located in the northwestern Aegean Sea, receiving water and sediment fluxes from the Axios, Aliakmon, Gallikos and Loudias Rivers. The geomorphological and sedimentological evolution of the system is reconstructed for the last 150 years (1850-2000), on the basis of detailed analysis of historical bathymetric charts. Late Holocene history is considered within the context of changing riverine sediment supply and human activities. Three evolutionary stages are identified. Stage I (1850-1916) corresponds to a natural phase of rapid deltaic progradation and sea-floor deposition, with an average sediment accumulation rate of 6.5 106 m3 a-1 . During Stage II (19461956), human interference (e.g. artificial changes in river delta plains, realignment of channels and land reclamation schemes) to the deltaic system increased sediment delivery to the coastal waters by a factor of three; this, in turn, enhanced the progradation of the active river mouth areas. In contrast, Stage III (1956-2000) is characterized by significant coastline (deltaic) retreat and erosion of the adjacent sea floor (net loss of 2.5 106 m3 a-1 ); this was as a result of extensive river damming, which trapped a significant part of the sediment moving seaward. Furthermore, these human impacts have affected the character of the surficial seabed sediments of the Gulf, by reducing the proportion of mud. The response of the deltaic margin of the Inner Thermaikos Gulf to various anthropogenic interventions seems to be analogous to that of other deltas in the Mediterranean region where large drainage projects, the development of irrigation networks and dam construction have taken place within their river basins. 1643 Sudden enhancement of sedimentation flux of210 Pbex as an indicator of lake productivity as exemplified by Lake Chenghai Wan G., Chen J., Xu S. et al. Science in China, Series D: Earth Sciences 2005 48/4 (484-495) The fundamental assumption of 210 Pb sediment dating is the stable flux of 210 Pbex , which was derived from atmosphere and then transferred into sediments via lake water. When the sedimentation rate is relatively constant, the 210 Pbex activity in sediments will be exponentially reduced with sedimentation age. 210 Pb ex in lake water is incorporated into sediments mainly via organic particulates. If the sedimentation flux of organic matter in lake water is suddenly increased, 210 Pbex will be significantly deposited and then transferred into sediments. On the one hand such sudden purification effect is obviously unfit for the fundamental assumption of 210 Pb dating; on the other hand, the sudden enhancement of 210 Pbex flux would be indicative of the conspicuous variation of primary productivity of lake water. This problem will be discussed in accordance with the variation trend of 210 Pbex in the vertical profile of recent sediments of Lake Chenghai, Yunnan Province. The sediment core was collected from the deep-water area of Lake Chenghai in June 1997. The vertical profile of 137 Cs activity is characterized by a tree-peak pattern. This profile gave reliable ages, and also showed the stability of sediment accumulation in the recent ten years. The vertical profile of 210 Pbex activity displays a specific distribution 312 SEDIMENTOLOGY of peaks, and is similar to the vertical profile of Corg . This phenomenon seems to be related to the mechanism of constraining the transfer of 210 Pbex into lake sediments. The average atomic ratios of Horg /Corg and Corg /Norg in Lake Chenghai sediments are 5.51 and 7.04, respectively, indicating that the organic matter was predominantly derived from the remains of endogenic algae. In terms of the three-stage evolutionary characteristics of organic matter in sediments, i.e., "deposition-decomposition-accumulation", the sedimentation fluxes (F(Corg)) of organic carbon (Corg ) since 1970 were calculated by modeling. The sedimentation fluxes of 210 Pb ex (F(210 Pbex )) in different years display good synchronous relations with the sedimentation flux of organic carbon (F(C org )), especially in the years of 1972-1974 and 19861989. The variation of F(Corg ) led to the variation of F(210 Pb ex ); the variation of F(210 Pbex ) reflects, to some extent, the historical variation of lake productivity. Copyright by Science in China Press 2005. 1644 Hydraulic behavior of tsunami backflows: Insights from their modern and ancient deposits Le Roux J.P. and Vargas G. Environmental Geology 2005 49/1 (65-75) Tsunamis are unpredictable, catastrophic events, and so present enormous difficulties for direct studies in the field or laboratory. However, their sedimentary deposits yield evidence of a wide variety of hydrodynamic conditions caused by flow transformations on a spatial and temporal scale. Tsunami deposits ranging from the Miocene to modern times identified at different localities along the Chilean coast are described to provide a database of their characteristics. Among the typical features associated with tsunami deposits are well-rounded megaclasts eroded from coastal alluvial fans or beaches by very dense, competent flows. Sand injections from the base of these flows into the substrate indicate very high dynamic pressures, whereas basal shear carpets suggest hyperconcentrated, highly sheared flows. Turbulence develops in front of advancing debris flows, as indicated by megaflutes at the base of scoured channels. © Springer-Verlag 2005. Sediments and sedimentary processes - diagenesis 1645 Facies-related diagenetic alteration in lacustrinedeltaic red beds of the Paleogene Ergeliin Zoo Formation (Erdene Sum area, S. Gobi, Mongolia) Dill H.G., Khishigsuren S., Melcher F. et al. Sedimentary Geology 2005 181/1-2 (1-24) The Late Eocene Ergeliin Zoo Formation, Mongolia, was subdivided into four facies associations/stratigraphic units which are characterized by various carbonate minerals: (I) mud-sand flat (low-Fe dolomite, high-Mg calcite), (II) delta front (high-Mn dolomite, low-Mg calcite), (III) delta plain (high-Mn calcite, low-Mg and moderate-Fe calcite), (IV) calcretes (high-Mg calcite). Besides carbonate minerals, prevailing among the cement minerals, some sheet silicates (Ca smectite, palygorskite, illite), apatite and Fe oxide-hydroxides occur in the siliciclastics of these lacustrine-deltaic red beds. The prodelta/mud-sand flat deposits (unit I) were dolomitized and cemented by high-Mg calcite during evaporative pumping at times of low lake-stand under redox conditions greater than 0 and intrastratal solutions of strong alkalinity. Manganoan dolomite is fairly widespread in the delta front sediments (unit II), the Mn content of which is likely to have been derived from decomposition of vertebrate remains. The Mn/Fe ratio in the carbonate minerals was controlled by the redox conditions and the shallow burial depth. In the porous delta front sediments Eh values around zero and pH values slightly above 7 occurred as a result of basinward fluid movements (high-Mn dolomite, high-Fe dolomite, low-Mg calcite). Fluid movement was locally impeded by finer-grained delta plain deposits (unit III), intertonguing with arenaceous aquifers (low Mg-moderate Fe calcite, high-Mn calcite). Higher up on the delta plain with deposits laid down in an environment transitional between distal alluvial and deltaic (unit IV), closed lake basin conditions reappeared as fluids emerged from the distal alluvial-fluvial deposits or were driven by capillary force to ascend and form calcretes abundant in Mg-bearing calcite. The climatic conditions in the Erdene Sum area, Mongolia, are likely to have been semi-arid transitional into arid. © 2005 Elsevier B.V. All rights reserved. 1646 Early diagenesis impact on precise U-series dating of deep-sea corals: Example of a 100-200-year old Lophelia pertusa sample from the northeast Atlantic Pons- Branchu E., Hillaire- Marcel C., Deschamps P. et al. Geochimica et Cosmochimica Acta 2005 69/20 (4865-4879) Deep-sea coral has proved useful for paleoceanographic reconstructions and for documenting 14 C-ages of water masses using 230 Th-ages. However, for precise and accurate U-series dating, further information on coral-age structure, growth rate and diagenetic evolution is still needed. To document such processes, we used U-Th-226 Ra systematics in a 40 cm diameter, Lophelia pertusa specimen collected in 1912 from the Eastern Atlantic (Sea of the Hebrides). External parts of the specimen are thought to have been alive when collected whereas more internal parts were likely dead. The "live-collected" and "dead" parts of the skeleton were sampled and analyzed for their 230 Th, 232 Th, 234 U, 238 U, 226 Ra and Ba contents by thermal ionization and multicollector inductively coupled plasma mass spectrometry. 230 Th/234 U ratios in the most recent parts yielded ages of 86 6 a and 92 9 a, in agreement with the date of recovery. The older parts yielded 230 Th ages ranging from 169 15 to 211 10 a (n = 5), but had a 31% higher U content than more recent parts of the skeleton. This raises concerns about the possibility of secondary diagenetic U uptake, although an environmentally controlled U/Ca shift between coral growth stages cannot be ruled out. 226 Ra/Ba measurements were made, and model- 226 Ra/Ba ages averaging 250 12 yr were calculated for the older part, assuming a constant initial 226 Ra/Ba ratio in bottom waters. These ages are slightly older than 230 Thages, suggesting either that 226 Ra/Ba ratios of ambient-seawater changed over time or that a diagenetic phenomenon have affected the U-series system, or both. Scanning electron microscope observations revealed bioerosion and secondary biomineralization in the older part of the coral skeleton, supporting the hypothesis that diagenetic processes may have influenced the ages obtained by the U-series toolbox. Modeled U-series ages for such an open system are discussed. However, a comparison between 14 C- and 230 Th-ages performed on both pristine and bioeroded parts of the coral gives coherent values (ca 450 a) for the preindustrial 14 C-reservoir age of North Atlantic waters. It remains to be determined, however, whether diagenesis occurs rapidly over a short period of time, or whether it continues for longer periods. In the latter case, diagenetic processes would hamper paleoceanographic interpretations as well as the precise calculation of 14 C ages of deep-water masses, based on comparative U/Th- and 14 C-chronologies. Copyright © 2005 Elsevier Ltd. 1647 Vertical variations in bassanite distribution patterns in near-surface sediments, southern Egypt Mees F. and De Dapper M. Sedimentary Geology 2005 181/3-4 (225-229) Nile valley sediments of the El Ada¨ıma area in southern Egypt contain bassanite (CaSO4 0.5H2 O), associated with gypsum (CaSO4 2H2 O), in the upper 1 m of the deposits. The presence of bassanite at this site, formed by dehydration of gypsum, is marked by variations in mode of occurrence with depth. In the lowest bassanite-bearing interval, bassanite occurs mainly along the contact between gypsum crystals in pores, which is related to the protection of bassanite from rehydration in those parts of the gypsum aggregates. At a higher level, bassanite occurs along the sides of lenticular gypsum crystals in the sediment matrix. Near the top of the studied sequence, bassanite mainly appears as inclusions in gypsum crystals, which represents a texture that developed by repeated dehydration and rehydration. Elsewhere in the upper part of the deposits, bassanite occurs as aggregates of small crystals in pores, without associated gypsum, which was entirely dehydrated to bassanite in these parts. These vertical variations in bassanite distribution patterns record differences in the diagenetic history of the deposits between depth intervals. © 2005 Elsevier B.V. All rights reserved. SEDIMENTOLOGY Sedimentary geochemistry 1648 Recent variations in sediment organic carbon content in Lake Soyang (Korea) Khim B.- K., Jung H.M. and Cheong D. Limnology 2005 6/1 (61-66) Four gravity cores were taken from Lake Soyang, which was created by the construction of an artificial dam in 1973. The variation of organic carbon content of the bottom sediments since the construction was interpreted using a variety of sedimentological and geochemical measurements. Based on the textural properties of sediments and the total organic carbon (TOC) content, it is clear that sediment organic carbon has been deposited very consistently throughout the postconstruction period, except for local sudden inputs caused by summer flooding events near fish farms or farmland areas. The autochthonous input resulting from the enhanced primary production led by phytoplanktons each year is likely to become a major problem at downstream sites within Lake Soyang. The vertical variation of 13 C values of sediment organic matter also reflects the fact that the level of autochthonous supply of organic carbon becomes high downstream. © The Japanese Society of Limnology 2005. 1649 Dynamics of redox changes of iron caused by lightdark variations in littoral sediment of a freshwater lake Gerhardt S., Brune A. and Schink B. Biogeochemistry 2005 74/3 (323-339) Depth profiles of oxygen concentration and the redox status of acid-extractable iron were measured in littoral sediment cores of Lake Constance incubated under a light-dark regimen of 12 h. While oxygen penetrated to 3.4 0.2 mm depth in the dark, photosynthetic oxygen production shifted the oxic-anoxic interface down to 4.0 0.2 mm or 5.9 1.6 mm depth, at low or high light intensity, respectively, and caused a net oxygen efflux into the water column. After a light-dark or dark-light transition, the oxygen concentration at the sediment surface reached a new steady state within about 20 min. The redox state of the bioavailable iron was determined in 1-mm slices of sediment subcores. After a dark period of 12 h, 85% of the acid-extractable iron (10.5 mol cm-3 total) in the uppermost 8 mm was in the reduced state. Within 12 h at low or high light intensity, the proportion of ferrous iron decreased to 82 or 75%, respectively, corresponding to net rates of iron oxidation in the range of 244 and 732 nmol cm-3 h-1 , respectively. About 55 or 82% of the iron oxidation at low or high light intensity occurred in the respective oxic zone of the sediment; the remaining part was oxidized in the anoxic zone, probably coupled to nitrate reduction. The areal rates of iron oxidation in the respective oxic layer (21 or 123 nmol cm-2 h-1 at low or high light intensity, respectively) would account for 4 and 23% of the total electron flow to oxygen, respectively. Light changes caused a rapid migration of the oxic-anoxic interface in the sediment, followed by a slow redox reaction of biologically available iron, thus providing temporal niches for aerobic iron oxidizers and anaerobic iron reducers. © Springer 2005. 1650 Redox changes of iron caused by erosion, resuspension and sedimentation in littoral sediment of a freshwater lake Gerhardt S. and Schink B. Biogeochemistry 2005 74/3 (341-356) Depth profiles of oxygen concentration and the redox status of acid-extractable iron were measured in littoral sediment cores of Lake Constance after mechanical removal of surface sediment, mixing, and re-deposition. In undisturbed sediment cores, oxygen penetrated down to 2.9 0.4 mm or 4.6 0.4 mm depth, respectively, after 12 h of incubation in the dark or light; causing a net diffusive flux of 108 20 nmol cm-2 h -1 oxygen into or 152 35 nmol cm-2 h-1 out of the sediment. The uppermost 20 mm layer of the undisturbed sediment cores contained 10.2 0.7 mol cm-3 ferrous and 3.8 1.1 mol cm-3 ferric iron. After erosion, the oxic-anoxic interface in the newly exposed sediment was shifted to about 2 mm depth within 30 min, causing an oxygen flow into the sediment. During the following 12 h, oxygen penetrated deeper into the sediment, and in the light oxygen was produced photosynthetically. Ferrous iron was largely oxidized within two days after erosion. The oxidation rates were higher in oxic than in anoxic sediment layers, and decreased with time. 313 This oxidation process took the longer and was confined closer to the surface the more reduced the exposed sediment had been before. Resuspension of eroded sediment in aerated lake water did not cause a significant oxidation or reduction of iron. After re-deposition, the oxic-anoxic interface in the re-sedimented material shifted to about 2 mm depth within 30 min, causing an oxygen flow into the sediment. During the following 12 h, the oxygen penetration depth and the oxygen flow rate into the re-deposited sediment did not change any further, and no oxygen was produced in the light. Ferric iron was reduced during the first day after re-deposition, and partly re-oxidized during the second day. The extent of reduction was stronger and the extent of oxidation weaker the more reduced the resuspended sediment was before. Oxic conditions in the sediment surface were established faster and ferrous iron was oxidized to a larger extent after erosion of sediment than after resuspension and sedimentation. © Springer 2005. 1651 Trace metal profiles in the varved sediment of an Arctic lake Outridge P.M., Stern G.A., Hamilton P.B. et al. Geochimica et Cosmochimica Acta 2005 69/20 (4881-4894) Varved (annually-laminated) sediments offer a rare and physically undisturbed archive of past trace metal deposition and limnological conditions. Here, a high-resolution 1,300 year record of metal accumulation is presented from a varved lake sediment on Devon Island in the Canadian High Arctic. Down-core concentration profiles of Cd, Cu and Zn were positively correlated (P < 0.01) with organic C (Cd, Zn) or with leachable Fe (Cu), while distinct sub-surface peaks of these metals coincided with those of Fe, S and other redox-sensitive elements such as Co, Cr and U. The fluxes of these metals since 1854 were correlated with elements such as Ca, Al and La (P < 0.001) which are predominantly of local geological origin. Furthermore, the Cd, Cu and Zn patterns did not match concurrent records in Greenland Summit ice over the last century, nor global industrial emission histories. These facts suggest that inputs from local geological sources, coupled with some degree of post-depositional mobility or association with organic matter inputs, explain the metals’ sedimentary profiles, which were apparently not affected by longrange atmospheric metal pollution. Mercury concentrations were strongly correlated with total diatom abundance over the last 400 yrs, especially during the 20th Century when a two-fold increase in Hg concentrations and a four order-of-magnitude increase in diatoms occurred in tandem. Since 1854, 81% of the variation in Hg flux was associated with diatom and Ca fluxes. A similar correspondence between Hg and diatoms was found in a second lake nearby, confirming that the relationship was not unique to the main study lake. Recent Hg increases in Arctic and sub-Arctic lakes have been attributed to global anthropogenic Hg emissions. We propose an alternative hypothesis for High Arctic lakes: the recent Hg increases may be partly or entirely the product of elevated rates of Hg scavenging from the water column caused by markedly greater algal productivity, which in turn was driven by accelerating climate warming during the 20th Century. Given the important environmental assessment and policy implications if the alternative hypothesis is true, the possible effects of climate warming on sedimentary Hg fluxes in this region deserve further study. Copyright © 2005 Elsevier Ltd. 1652 Sea bottom anoxia in the Archipelago Sea, northern Baltic Sea - Implications for phosphorus remineralization at the sediment surface Virtasalo J.J., Kohonen T., Vuorinen I. and Huttula T. Marine Geology 2005 224/1-4 (103-122) The effects of the hydrophysical environment on oxygen conditions and P remineralization at sediment surface were studied in the Archipelago Sea, northern Baltic Sea. At 94 sites, the water column was profiled for conductivity, temperature and oxygen, and the topmost sediment was collected for P and C fractions and (oxy)hydroxide Fe analysis. The near-bottom water and sediment parameters as well as visual observations on the vertical colour distribution in the sediment cores were used to statistically classify the sediment surfaces into oxic, anoxic and suboxic (fluctuating oxygen conditions) bottoms. The anoxic bottoms occurred in the basins with water depths less than 47 m, and the suboxic bottoms were most common in the basins with depths 314 SEDIMENTOLOGY between 20-60 m, while the oxic bottoms dominated in the depths over 60 m. It was concluded that the preferential development of oxygen deficiency in the shallow basins results from the combined effects of complex topography and seasonal temperature stratification on both vertical and lateral bottom water exchange. In the anoxic bottoms, C / P ratios suggest enhanced release of P compared to the oxic and suboxic bottoms. In the suboxic bottoms, high inorganic P concentrations and the strong coupling between P and Fe suggest active transformation of organic P to the inorganic P phases, probably due to the fluctuating oxygen conditions. Differences in the spatial distribution of the P, C and Fe were insignificant except for detrital P, which decreased seawards. © 2005 Elsevier B.V. All rights reserved. 1653 Revisiting the rare earth elements in foraminiferal tests Haley B.A., Klinkhammer G.P. and Mix A.C. Earth and Planetary Science Letters 2005 239/1-2 (79-97) Are the rare earth elements (REEs) in foraminifera a valuable proxy for use in paleoceanographic and climate change studies? In order to investigate this, we attempted a comprehensive study of REEs in planktonic and benthic foraminifera. Several different cleaning protocols were tested. Although the hydroxylamine used to clean all foraminifera in this study removes an unidentified source of REE contamination, it seems to remobilize metal oxides that are otherwise unaffected in flow-through dissolution. The calculated REE distribution coefficients, KD(REE) s, are between 100 and 500 for both planktonic and benthic foraminifera. These KD s are high compared to other elements in biogenic calcite but can be explained through a general model of element incorporation during foraminiferal calcification. From data taken from eight core tops in the southeast Pacific, we conclude that the REEs in planktonic foraminifera are, indeed, useful as a proxy for upper ocean water mass and mixed layer biogenic productivity. Alternatively, the REEs in benthic foraminifera are useful as a proxy for carbon flux to the sea floor. These proxies should be robust down core unless the sediments have undergone anoxic diagenesis, which stabilizes Fe carbonate thus overprinting the primary REE signature. However, it is clear from REE distributions in foraminiferal tests if anoxic conditions have occurred. © 2005 Elsevier B.V. All rights reserved. 1654 Fluid sources, fluid pathways and diagenetic reactions across an accretionary prism revealed by Sr and B geochemistry Teichert B.M.A., Torres M.E., Bohrmann G. and Eisenhauer A. Earth and Planetary Science Letters 2005 239/1-2 (106-121) ODP Leg 204, which drilled at Hydrate Ridge, provides unique insights into the fluid regime of an accretionary complex and delineates specific sub-seafloor pathways for fluid transport. Compaction and dewatering due to smectite-illite transition increase with distance from the toe of the accretionary prism and bring up fluids from deep within the accretionary complex to sampled depths ( 600 mbsf). These fluids have a distinctly non-radiogenic strontium isotope signature indicating reaction with the oceanic basement. Boron isotopes are also consistent with a deep fluid source that has been modified by desorption of heavy boron as clay minerals change from smectite to illite. One of three major horizons serves as conduit for the transport of mainly fluid. Our results enable us to evaluate fluid migration pathways that play important roles on massive gas hydrate accumulations and seepage of methane-rich fluids on southern Hydrate Ridge. © 2005 Elsevier B.V. All rights reserved. 1655 Elemental composition of calcites in late Quaternary pedogenic calcretes from Gujarat, western India Khadkikar A.S. Journal of Asian Earth Sciences 2005 25/6 (893902) Pedogenic calcretes commonly exhibit clotted micrite, circumgranular calcite (grain coats) and microspar/spar veins. The three calcite-types with different dimensions were analyzed for their magnesium content to determine the relationship between crystal elongation and magnesium incorporation. The results show a very low MgO content for grain coats and microspars and high values for clotted micrite indicating that the ideal kinetic model does not hold true and several variables govern the end composition of calcites. The magnesium concentrations of meteoric calcites are genetically linked to the evolutionary history of the soil and climate. Grain coats, which are elongated calcites, contain the least amount of Mg and is related to the initial stages of pedogenesis wherein the limiting factor is the Mg/Ca ratio of the parent fluid. Lower magnesium contents arise due to smaller quantities of Mg being released during incipient weathering. Micrite morphology and composition is controlled by the greater availability of Mg ions through weathering, higher pCO2 in soil due to increased time-dependent soil respiration, which causes a rise in calcite precipitation rates and clay authigenesis. This in turn exerts a physical control on morphology by occluding pore space and providing numerous nuclei for calcite precipitation. The wide variability in spar cements is inherently controlled by inhomogeneties in parent fluid compositions with lower-thanmicrite values on account of slower precipitation rates. © 2004 Elsevier Ltd. All rights reserved. 1656 Characterization and origin of Fe3 +- montmorillonite in deep-water calcareous sediments (Pacific Ocean, Costa Rica margin) Gaudin A., Buatier M.D., Beaufort D. et al. Clays and Clay Minerals 2005 53/5 (452-465) Millimetric to centimetric green grains widespread in pelagic calcareous sediments recovered at a water depth of 3000 in near the Costa Rica margin were studied by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy. Samples were collected, during the Ticoflux II expedition, from the upper bioturbated part of four sedimentary cores (0.13-3.75 in below seafloor). The sediments are calcareous and siliccous nanofossil oozes (coccoliths, diatoms, radiolarians, etc.). Green grains show generally a concentric zoning with a green rim in which smectite largely predominates over pyrite and a black core in which pyrite is prevalent. Observations by SEM indicate that this zoning results from a progressive inward alteration and replacement of the accumulations of pyrites by smectites. The high-resolution TEM observations of the smectite-pyrite interfaces suggest that the replacement of pyrites by smectite occurs through a dissolution-precipitation process with the formation of a gel. The pyrite matrix is composed of a huge number of very small (0.5-2 m) pyrite octahedra, a typical texture resulting from the pyritization of organic material in early diagenetic environments. The accurate mineral ogical and crystal chemical characterization of the smectites indicate that they are Fe3+ -montmorillonites (Fe3+ -rich smectite with a dominant octahedral charge, rarely recorded in the literature). The formation of such Fe3+ -montmorillonites forming green grains could be explained by two successive diagenetic redox stages: (1) reducing stage: early pyritization of the organic matter by microbial reduction within reducing micro-environments; (2) oxidizing stage: Fe3+ -montmorillonite crystallized in space liberated after dissolution of pyrite connected with the rebalancing of the redox conditions of the micro-environments with the oxidizing surrounding sediments. Copyright © 2005, The Clay Minerals Society. 1657 REE and Nd of clay fractions in sediments from the eastern Pacific Ocean: Evidence for clay sources Liu J., Shi X., Chen L. et al. Science in China, Series D: Earth Sciences 2005 48/5 (701-712) Clay fractions in the non-calcareous surface sediments from the eastern Pacific were analyzed for clay minerals, REE and 143 Nd/ 144 Nd. Montmorillonite/illite ratio (M/I ratio), total REE contents (REE), LREE/HREE ratio and cerium anomaly ( Ce) may effectively indicate the genesis of clay minerals. Clay fractions with M/I ratio >1, Ce <0.85, REE >400 g/g, LREE/HREE ratio 4, and REE patterns similar to those of pelagic sediments are terrigenous and autogenetic mixed clay fractions and contain more autogenetic montmorillonite. Clay fractions with M/I ratio <1, Ce=0.86 to 1.5, REE=200 to 350 g/g, LREE/HREE ratio 6 and REE distribution patterns similar to that of China loess are identified as terrigenous clay fraction. The 143 Nd/144 Nd ratios or Nd values of clay fractions inherit the features of terrigenous sources of clay minerals. Clay fractions are divided into 4 types according to Nd values. Terrigenous clay minerals of type I with the Nd values of -8 to -6 originate mainly from North American fluvial deposits. Those of type II with the Nd values of -9 to -7 are mainly from the East Asia and North American SEDIMENTOLOGY fluvial deposits. Those of type III with Nd values of -6 to -3 could come from the central and eastern Pacific volcanic islands. Those of type IV with Nd values of -13 to -12 may be from East Asia eolian. The terrigenous and autogenetic mixed clay fractions show patchy distributions, indicating that there are volcanic or hot-spot activities in the eastern Pacific plate, while the terrigenous clay fractions cover a large part of the study area, proving that the terrigenous clay minerals are dominant in the eastern Pacific. Copyright by Science in China Press 2005. 1658 Trace elements in streambed sediments of small subtropical streams on O’ahu, Hawai’i: Results from the USGS NAWQA program De Carlo E.H., Tomlinson M.S. and Anthony S.S. Applied Geochemistry 2005 20/12 (2157-2188) Data are presented for trace element concentrations determined in the <63 m fraction of streambed sediment samples collected at 24 sites on the island of O’ahu, Hawai’i. Sampling sites were classified as urban, agricultural, mixed (urban/agricultural), or forested based on their dominant land use, although the mixed land use at selected sampling sites consisted of either urban and agricultural or forested and agricultural land uses. Forest dominated sites were used as reference sites for calculating enrichment factors. Trace element concentrations were compared to concentrations from studies conducted in the conterminous United States using identical methods and to aquatic-life guidelines provided by the Canadian Council of Ministers of the Environment. A variety of elements including Pb, Cr, Cu and Zn exceeded the aquatic-life guidelines in selected samples. All of the Cr and Zn values and 16 of 24 Cu values exceeded their respective guidelines. The potential toxicity of elements exceeding guidelines, however, should be considered in the context of strong enrichments of selected trace elements attributable to source rocks in Hawai’i, as well as in the context of the abundance of finegrained sediment in the streambed of O’ahu streams. Statistical methods including cluster analysis, Kruskal-Wallis non-parametric test, correlation analysis, and principal component analysis (PCA) were used to evaluate differences and elucidate relationships between trace elements and sites. Overall, trace element distributions and abundances can be correlated to three principal sources of elements. These include basaltic rocks of the volcanic edifice (Fe, Al, Ni, Co, Cr, V and Cu), carbonate/seawater derived elements (Mg, Ca, Na and Sr), and elements enriched owing to anthropogenic activity (P, Sn, Cd, Sn, Ba and Pb). Anthropogenic enrichment gradients were observed for Ba, Cd, Pb, Sn and Zn in the four streams in which sediments were collected upstream and downstream. The findings of this study are generally similar to but differ slightly from previous work on sediments and suspended particulate matter in streams, from two urban watersheds of O’ahu, Hawai’i. Inter-element associations in the latter were often stronger and indicated a mixture of anthropogenic, agricultural and basaltic sources of trace elements. Some elements fell into different statistical categories in the two studies, owing in part to differences in study design and the hydrogeological constraints on the respective study areas. 1659 Sequential Factor Analysis as a new approach to multivariate analysis of heterogeneous geochemical datasets: An application to a bulk chemical characterization of fluvial deposits (Rhine-Meuse delta, the Netherlands) Van Helvoort P.- J., Filzmoser P. and Van Gaans P.F.M. Applied Geochemistry 2005 20/12 (2233-2251) Sequential Factor Analysis (seqFA) is presented here as an enhanced alternative to multivariate factorial techniques including robust and classical Factor Analysis (FA) or Principal Component Analysis (PCA). A geochemical data set of 145 sediment samples from very heterogeneous, mainly riverine, deposits of the Rhine-Meuse delta (The Netherlands) analyzed for 27 bulk parameters was used as a test case. The innovative approach explicitly addresses the priority issues when performing PCA or FA: heterogeneity and overall integrity of the data, the number of factors to be extracted, and which optimum minimal set of key variables to be included in the model. The stepwise decision process is based on quantitative and objectively derived statistical criteria, yet also permitting arguments based on geochemical expertize. The results show that seqFA, preferably in combination with robust methods, yields a highly consistent factor model, and 315 is favorable over classical methods when dealing with heterogeneous data sets. It optimizes rotation of the factors, and allows the extraction of less distinct factors supported by only a few variables, thus uncovering additional geochemical processes and properties that would easily be missed with other approaches. The identification of key variables simplifies the geochemical interpretation of the factors, and greatly facilitates the construction of a geochemical conceptual model. For the case of the fluvial deposits, the conceptual model effectively describes their bulk chemical variation in terms of a limited number of governing processes. © 2005 Elsevier Ltd. All rights reserved. 1660 Late Holocene geochemical history inferred from Sambhar and Didwana playa sediments, Thar Desert, India: Comparison and synthesis Roy P.D., Smykatz- Kloss W. and Sinha R. Quaternary International 2005 144/1 (84-98) The Sambhar and Didwana playas from the eastern margin of the Thar Desert (annual precipitation of 300-450 mm) have been investigated for mineralogy, major and trace element geochemistry of near surface sediments. Geochemical data and evaporite mineralogy of sediments from the playa surface and shallow depths provide insight to the present-day geochemical processes and the different vertical phases of pore water activity. Detrital minerals from both the playas reflect igneous and metamorphic source rocks in their catchments. The zeolite type mineral, analcime (NaAlSi2 O6 H2 O) is assumed to be authigenic in origin, a product of chemical reaction between the hypersaline brine and detrital feldspars. The evaporite mineralogy is dominated by halite, calcite and dolomite. Major differences between the evaporite mineralogy of the surface sediments of two playas are the occurrence of trace amounts of the H2 O-bearing carbonate, trona (Na3 H(CO3 )2 2H2 O), in the Didwana and K- and Mgbearing sulphate and chloride minerals e.g. polyhalite (K2 MgCa2 (SO4 )4 2H2 O), carnallite (KMgCl3 6H2 O), and sylvite (KCl) in the Sambhar. Based on the distribution of major and trace elements, the surface sediments from both playas are divided into three geochemical zones. Fed by river and rainwaters, the playa surfaces show enrichment of insoluble cations and hydrolysates in the outermost zone and soluble oxides and cations in the innermost zone. Further, the shallow depth profiles are also divided into distinct geochemical zones based on the elemental ratios. The sub-recent zone I reflects low chemical weathering and higher aeolian input, the middle zone II indicates relatively higher weathering index and zone III, enriched in evaporites, also shows low chemical weathering. Despite the fact that the Sambhar and Didwana are separated only by 50 km, they show significant differences in terms of evaporite mineralogy and inorganic composition of surface sediments. We interpret this to be a manifestation of local variations in precipitation, inflow and aeolian influx. © 2005 Elsevier Ltd and INQUA. All rights reserved. Sedimentary environments terrestrial 1661 Sedimentation problems and management strategies of Sanmenxia Reservoir, Yellow River, China Wang G., Wu B. and Wang Z.- Y. Water Resources Research 2005 41/9 (1-17) [1] Reservoir sedimentation management is of critical importance for the sustainable development of surface water resources. Sanmenxia Dam, located on the middle reach of the Yellow River, in China, is notorious for its severe sedimentation problems. Because of the alarming rate of loss of reservoir storage capacity and the unacceptable negative impact induced by the rapid upstream extension of sediment deposited in the river’s backwater region, the dam has been reconstructed to provide high sediment releasing capacity, and the dam operation has been changed in order to achieve a balance between sediment inflow and outflow. As a result, the dam is still providing the basin with flood control, irrigation, and hydropower generation, even though some benefits are lower than the original design. Complex sedimentation processes in response to the dam reconstruction and changes 316 SEDIMENTOLOGY of dam operation are discussed in this paper. The engineering experiences and management practices of Sanmenxia Dam are valuable assets to the sustainable use of reservoirs built on sediment-laden rivers. Copyright 2005 by the American Geophysical Union. 1662 Sediment provenances and drainage evolution of the Neogene Amazonian foreland basin Roddaz M., Viers J., Brusset S. et al. Earth and Planetary Science Letters 2005 239/1-2 (57-78) During the Middle-Late Miocene, tidal sedimentation was the rule in the Amazon foreland basin. The Amazon foreland basin became emerged in the Late Miocene-Pliocene times. In this study, trace element chemistry (n = 104) and Nd-Sr isotopic systematic (n = 30) are used to constrain the provenance of the Miocene tidal sediments and of the Late Miocene-Pliocene fluvial sediments. Neogene Amazonian foreland basin sediments are the result of a mixing between Andean andesitic volcanic rocks and cratonic shield rocks. The south Amazonian foreland basin (SAFB) sediments are the result of long-term weathering, recycling, and erosion of the Brazilian shield and Andean Paleozoic/Mesozoic rocks also Brazilian shield in provenance. Compared with north Amazonian foreland basin (NAFB) sediments, SAFB sediments are more felsic. NAFB sediments have 3 distinct signatures: i) an upper crust signature with trace element characteristics similar to PAAS and UCC and with Nd(0) values between - 8 and - 11.9; ii) an arc andesitic rock signature with high Cr/Th ratios, low Eu anomalies, low Th/Sc ratios and Nd(0) values between - 3 and - 5; and iii) a cratonic signature with high Eu anomalies and Zr/Sc ratios and with a very low Nd(0) value (-15.5). Our data indicate that most of the basic detritus came from the Ecuadorian Andes. In the distal part of the NAFB, the successive uplifts of the Iquitos forebulge were responsible for Late Miocene to Pliocene divide between Andean and cratonic drainage systems. The modern "Amazon River" drainage network is no younger than the Pliocene. © 2005 Elsevier B.V. All rights reserved. 1663 Distribution of high-level alluvial deposits in the valley and ridge of Polk County, southeastern Tennessee: Implications for river history and drainage evolution Mills H.H., Sumners D.N., Hart E.A. and Li P. Southeastern Geology 2005 44/1 (37-44) Surficial mapping based on digital soil maps along the Hiwassee and Ocoee Rivers in western Polk County, Tennessee, shows almost 100 square kilometers of alluvium. By far the most extensive is high-level alluvium resting on carbonate bedrock, mainly on the Knox Group. This old alluvium covers rolling topography at elevations of roughly 15 m or greater above the modern river level (ARL), extending to 80 m ARL locally. It is highly weathered, with B horizons having clay percentages exceeding 50 percent and Munsell hues of typically 2.5YR. Sandstone clasts, where present, generally are decomposed. Deposits lower than 15 m ARL occur on floodplains and low terraces are much less weathered, with clay percentages less than 30 and colors no redder than 7.5YR. Pebbles and cobbles of vein quartz attest to the origin of most alluvium in the Blue Ridge province. Such clasts become less common with increasing height ARL, and at the highest levels regolith consists of scattered quartz clasts mixed with carbonate residuum. Alluvial deposits generally occur within 4 km of the main rivers. An exception is a band of high-level alluvium extending from the Ocoee south-southwesterly to the Conasauga River near the Tennessee-Georgia border. This band crosses a prominent divide between the Tennessee and Coosa River basins where only small, local streams flow today. Its presence suggests either that the Conasauga, currently a tributary to the Coosa, once flowed north to the Tennessee River, or else that the Ocoee, now a tributary of the Tennessee, once flowed south to the Coosa. 1664 Deposition of playa windblown dust over geologic time scales Pelletier J.D. and Cook J.P. Geology 2005 33/11 (909-912) Thick eolian deposits are commonly observed beneath desert pavements downwind of dust-emitting playas. These deposits play an important role in piedmont-surface evolution, controlling surface hydrologic conductivity and rates of pedogenesis. To better understand the factors controlling the spatial distribution of eolian deposition, we developed a numerical model that treats deposition from spatially distributed playa sources using analytic point-source solutions for deposition from a Gaussian plume. The model also accounts for complex downwind topography. As a test case, model predictions were compared to eolian deposit thicknesses on Eagle Mountain piedmont, southern Amargosa Valley, California, which receives dust from nearby Franklin Lake playa. The close relationship between the model predictions and mapped thicknesses suggests that eolian transport and deposition can be modeled from basin to regional scales within this framework. These results have important implications for hydrologic, pedogenic, and air-quality problems. © 2005 Geological Society of America. 1665 Fractal river networks of Southern Africa Stankiewicz J. and de Wit M.J. South African Journal of Geology 2005 108/3 (333-344) Fractals and scaling laws abound in nature, and it is said that geometry of river networks and basins is an epitome of this. This study investigates how, in the southern section of the tectonically unique African continent, scaling parameters and deviations from ‘perfect fractal patterns’ relate to parameters like geomorphology through which the river flows, and the underlying geology. A number of river network scaling laws and scaling parameters have been put forward, but it has been suggested that all river networks can be divided into universality classes represented by just 2 of these scaling parameters. One of these is the fractal dimension of individual streams, usually labelled d and having a value of 1.1. The other parameter, Hack’s exponent h, expresses the dependence of stream length (l) on drainage area (a) via Hack’s Law l = cah . There is no universal value for h. Different networks often have different values for h, and inside a given network the parameter is often observed to change with scale. We use the natural laboratory of networks in southern Africa to investigate the variations in Hack’s exponent and find evidence to confirm the existence of scaling regimes. We attempt to explain these variations in scaling using the regime model of Dodds and Rothman (2000). At the smallest scale we find that non-convergent mountain streams exist in different settings, but their spacing is determined by underlying rock type. in this type of drainage a1, and hence h 1. Once streams begin to converge, the value of h drops, and is inversely correlated to the roughness of the underlying topography. This trend stops once basin sizes reach a threshold value, above which basins may be self-similar. This threshold varies in individual networks. In the smoothest topographies it occurs as low as 400 km2 , but can occur as high as 1400 km2 in other networks. While we have identified a number of guidelines for correlating scaling parameters with basin settings, there exist significant variations around these guidelines which we can only attribute to randomness, or small variations in the initial conditions during the initial formation of the river basins. © 2005 Geological Society of South Africa. 1666 A lithofacies terrain model for the Blantyre Region: Implications for the interpretation of palaeosavanna depositional systems and for environmental geology and economic geology in southern Malawi Dill H.G., Ludwig R.- R., Kathewera A. and Mwenelupembe J. Journal of African Earth Sciences 2005 41/5 (341-393) The Blantyre City Area is part of the African savanna in southern Malawi. Sedimentological, geomorphological, chemical and mineralogical studies were conducted to create a lithofacies terrain model. The project involves mapping, cross-sectioning, grain size, heavy mineral analysis, XRD and the study of sedimentary textures under the petrographic microscope. These classical techniques were combined with GIS-based field and office works. The combined efforts led to 2-D maps and 3-D block diagrams that illustrate the geomorphological and sedimentological evolution of the landscape in southern Malawi during the late Mesozoic and Cenozoic. The results obtained through integrated geomorphological-sedimentological studies form the basis for land management (planning of residential areas, waste disposal sites, assessment of bearing capacity of rocks), geohazard prediction (delineation of high risk zones in terms of mass flow and inundation) and the evaluation of high-place (ceramic raw materials) and high-unit value (placers of precious metals SEDIMENTOLOGY and gemstones) mineral commodities in the study area. The study addresses regional and general aspects alike. In regional terms, the study aimed at unraveling the evolution of landforms at the southern end of the East African Rift System during the most recent parts of the geological past. Four stages of peneplanation were established in the working area. Planation was active from the Cretaceous to the Quaternary (stage I: early to mid-Cretaceous, stage II: early Tertiary, stage III: early to midTertiary, stage IV: mid- to late Tertiary). During the most recent parts of the Quaternary, strong fluvial incision was triggered by the base-level lowering of the Shire River. Geomorphological alteration of the landscape goes along with a phyllosilicate-sesquioxide transformation from minerals indicative of more acidic meteoric fluids (e.g., gibbsite, kaolinite) to those typical of more alkaline conditions (e.g. smectite, vermiculite, hydrobiotite). In addition, the investigation is to provide some characteristic features suitable for the recognition and interpretation of terrestrial environments resembling the present-day savanna in the ancient sedimentary record: (1) Conspicuous bimodality in the grain-size distribution. (2) High degree of gravel roundness. (3) Boulder fields (basal conglomerates) with fitting breccias and no rotation of structural elements. (4) Poor to very poor sorting of siliciclastics. (5) Stratification is rare; if present only in sandy beds with antidune and tabular cross-bedding at low angle prevailing over crossbedding at high angle. (6) Grading rare; in arenaceous deposits poorly developed FU sequences, in rudites poorly developed CU sequences, locally with surface armoring. (7) Directional sedimentary structures in coarse-grained deposits are unimodal. Fabric types: a(t)b(i) and a(p)b(i); shear planes indicative of slide may be present. (8) Ribbon-shaped architectural elements prevail over channel-like types. Bounding surfaces/unconformities are uneven to wavy and more widespread than scour-and-pool structures. (9) Fine-grained carbonaceous interbeds are restricted to shallow depressions. (10) Etch marks such as tafonis, flutes, honeycomb textures are common. (11) Placer deposits of metallic and non-metallic mineral commodities are abundant. (12) Alucretes and ferricretes of bog iron (ferrihydrite & gt; goethite) and lateritic (goethite > ferrihydrite) types are common, calcitic freshwater limestones and gypcretes are scarce. (13) Kandite-group minerals "in" (relic), smectite-group minerals "in", vermiculite "in" (recent), mica-group minerals "out". © 2005 Elsevier Ltd. All rights reserved. Sedimentary environments - coastal and shallow marine 1667 The interplay of eustasy, climate and human activity in the late Quaternary depositional evolution and sedimentary architecture of the Po Delta system Stefani M. and Vincenzi S. Marine Geology 2005 222-223/1-4 (19-48) The late Pleistocene and Holocene environmental evolution and sequence stratigraphic architecture of the Po Delta region, Northern Italy, are examined. The study units record the depositional evolution from lowstand continental accumulation to marine transgression and highstand progradation. Interpretation of the high-resolution, three-dimension geological mapping of the central Po Delta area was framed within the evolution of the whole of the delta region, stretching from Venice Lagoon to the South of Ravenna. The development of the delta lobes was correlated with the fluvial drainage history. A discussion on the different auto and allocyclic mechanisms controlling the depositional evolution and a quantitative estimation of the changing depositional rates are also provided. Outcrop study was based on field surveying and on the analysis of aerial photography, topographic micro-relief, historical cartography, archaeological and historiographic data. Subsurface analysis was based on stratigraphic coring and cone penetration testing. During the last glacial lowstand, the modern coastal region was the site of middle alluvial plain sedimentation. Deglaciation and early transgression were associated with an erosive disconformity development. In the modern coastal area, transgressive accumulation started between 10 and 9000 yr BP. Back-stepping fluvial and brackish marsh deposits were followed by delta-estuarine sand bodies, influenced by the last 317 important eustatic rise pulses. Transgression climaxed at about 5500 yr BP, during a warm climate phase. Early highstand saw the growth of large sand spits and barrier islands, progressively turning the previous bays into confined lagoons. At about 35003000 yr BP, a particularly active meteo-marine regime profoundly affected the depositional dynamics. Etruscan and Roman times were characterised by a warm climate and by riverine stability associated with the development of a large delta lobe. At around 1500 yr BP, transition toward moister and cooler conditions and the abandoning of the Roman Empire hydraulic works coincided with important drainage network instability. The modern delta lobe was induced 400 years ago by an artificial fluvial-mouth cut. The early evolution of the lobe recorded very high accumulation rates. The modern fragile environmental situation is characterised by strong coastal erosion and difficult management. © 2005 Elsevier B.V. All rights reserved. 1668 Event beds in the recent prodelta stratigraphic record of the small flood-prone Bonea Stream (Amalfi Coast, Southern Italy) Budillon F., Violante C., Conforti A. et al. Marine Geology 2005 222-223/1-4 (419-441) Seismic interpretation of about 150 km of high resolution Sonar Chirp lines, matched with cores collected off the Bonea Stream mouth (Salerno Bay, Southern Tyrrhenian Sea) were used in the detection of event beds interlayered in the pelitic Late Holocene shelf wedge. Grain fabric, textures and absolute dating of core sediment allowed to identify the most recent event bed as being the coarse deposit that settled following the disastrous flood of the Bonea Stream in 1954 A.D. Below this event bed, three others, consisting of sharp-based and graded sand layers, were recognized as well. Their lithology, texture and lateral geometry point to a diverse dynamic of deposition, involving the reworking and winnowing of fluvial and littoral sand such as seastorm-induced, downflow currents. The unusual thickness of tempestite sandy layers has been linked to the large availability of sand delivered to the coastal system by recurrent floods in the area and to the fast burial rate. Magnetic susceptibility correlations calibrated by a dated core, by 210 Pb and 137 Cs geochronology and by the 1822 A.D. Vesuvius tephra and seismic stratigraphic evidences, led to constrain these events to the last 1000 yr. © 2005 Elsevier B.V. All rights reserved. 1669 Autogenic cyclicity of foreset sorting in experimental Gilbert-type deltas Kleinhans M.G. Sedimentary Geology 2005 181/3-4 (215-224) Gilbert-type deltas are commonly characterised by steep foreset bedding. Changes in the foreset characteristics such as grain size, grading, alternating sand and gravel are often interpreted as records of changes of base level or sediment input due to diurnal, seasonal or climatic forcing. To aid such interpretations, an important question is to what extent cyclicity in the foreset characteristics can be explained by autogenic processes rather than exogenic forcing. Experimental deltas were generated with gravelly sand under constant boundary conditions and a varying width-depth ratio of the feeder system. The foresets of the narrow feeder system are regular and show gradual upward fining. The foresets of the wide feeder system, in contrast, show quasi-cyclic patterns of coarsening and fining during the delta progradation. The cyclicity is caused by the emergence of a channelised point feeder system with migrating gravel side bars, which distributes the sand and gravel laterally in a non-uniform manner. This spectacular change of foreset architecture is fully explained by the autogenic response of the feeder system to the width. These experiments are contrasted with experiments and data from literature in the framework of the delta classification of Postma [Postma, G., 1990. Depositional architecture and facies of river and fan deltas: a synthesis. In: Colella, A. and Prior, D.B. (eds), 1990. Coarse-grained Deltas. Spec. Publ. 10 of the Int. Ass. of Sedimentologists, Blackwell Scientific, Oxford, UK, 13-28]. © 2005 Elsevier B.V. All rights reserved. 318 SEDIMENTOLOGY Sedimentary environments - oceanic 1670 Sedimentary architecture of a Plio-Pleistocene protoback-arc basin: Wanganui Basin, New Zealand Proust J.- N., Lamarche G., Nodder S. and Kamp P.J.J. Sedimentary Geology 2005 181/3-4 (107-145) The sedimentary architecture of active margin basins, including back-arc basins, is known only from a few end-members that barely illustrate the natural diversity of such basins. Documenting more of these basins types is the key to refining our understanding of the tectonic evolution of continental margins. This paper documents the sedimentary architecture of an incipient back-arc basin 200 km behind the active Hikurangi subduction margin, North Island, New Zealand. The Wanganui Basin (WB) is a rapidly subsiding, Plio-Pleistocene sedimentary basin located at the southern termination of the extensional back-arc basin of the active Central Volcanic Region (TVZ). The WB is asymmetric with a steep, thrust-faulted, outer (arc-ward) margin and a gentle inner (craton-ward) margin. It contains a 4-km-thick succession of Plio-Pleistocene sediments, mostly lying offshore, composed of shelf platform sediments. It lacks the late molasselike deposits derived from erosion of a subaerial volcanic arc and basement observed in classical back-arc basins. Detailed seismic stratigraphic interpretations from an extensive offshore seismic reflection data grid show that the sediment fill comprises two basin-scale mega-sequences: (1) a Pliocene (3.8 to 1.35 Ma), sub-parallel, regressive "pre-growth" sequence that overtops the uplifted craton-ward margin above the reverse Taranaki Fault, and (2) a Pleistocene (1.35 Ma to present), divergent, transgressive, "syn-growth" sequence that onlaps: (i) the craton-ward high to the west, and (ii) uplifted basement blocks associated with the high-angle reverse faults of the arc-ward margin to the east. Along strike, the sediments offlap first progressively southward (mega-sequence 1) and then southeastward (mega-sequence 2), with sediment transport funnelled between the craton- and arcward highs, towards the Hikurangi Trough through the Cook Strait. The change in offlap direction corresponds to the onset of arc-ward thrust faulting and the rise of the Axial Ranges at ca 1.75 Ma, resulting in 5100-5700 m of differential subsidence across the fault system. Sedimentation has propagated south- to southeast-ward over the last 4 Myrs at the tip of successive backarc graben, volcanic arcs and the associated thermally uplifted parts of the North Island, following the southward migration of the Hikurangi subduction margin. Subsidence occurred by mantle flow-driven flexure, the result of active down-drag of the lithosphere by locking of the Hikurangi subduction interface and sediment loading. The WB is considered to be a proto-back-arc basin that represents the intermediate stage of evolution of an epicratonic shelf platform, impacted by active margin processes. © 2005 Elsevier B.V. All rights reserved. Applied sedimentology 1671 Manganese and iron accumulation in a eutrophic, submontane dam reservoir - The role of speciation Szarek-Gwiazda E. Oceanological and Hydrobiological Studies 2005 34/3 (125-139) The manganese and iron in the water and sediments of the submontane, eutrophic Dobczyce Dam Reservoir (southern Poland) was partitioned. Manganese and iron occurred mainly in the particulate phases in the water. In the sediments, approximately 77% of Mn was bound to exchangeable carbonate and easily reducible fractions, whereas approximately 90% of Fe was bound to moderately reducible fractions and residues. The cumulation coefficient (K) indicated that Mn, the more "mobile" element, accumulated in lower amounts in the sediments (K=7200) than did Fe (K = 51000). Element partitioning in the sediments was an important factor in determining the level of accumulation. 1672 Occurrence of pesticides, polychlorinated biphenyls (PCBs), and heavy metals in sediments from the Dniester River, Moldova Sapozhnikova Y., Zubcov E., Zubcov N. and Schlenk D. Archives of Environmental Contamination and Toxicology 2005 49/4 (439448) The aim of this study was to evaluate sediments of the Dniester River, in the former Soviet republic of Moldova, for the occurrence of agricultural pesticides, polychlorinated biphenyls (PCBs), and heavy metals. In October 2001, sediment samples were collected at three locations of the Dniester River: upstream, downstream, and at the tributary of the River Byk. DDT and its metabolites were observed most frequently. Total DDT sediment concentrations ranged from 8.2 to 34.7 ng/g dry weight with the highest average concentration detected at the tributary location. Heptachlor epoxide (< 0.2-3.0 ng/g dry weight), chlordane (< 0.1-6.1 ng/g dry weight), endrin (< 0.2-2.5 ng/g dry weight), phosalone (< 0.2-1.1 ng/g dry weight), and methylparathion (< 0.2-16.8 ng/g dry weight) were also detected. Total PCB concentrations observed in sediments ranged from 68 to 763 ng/g dry wt. Total average PCB concentrations were significantly (p 0.004) higher for sediments from the downstream sampling sites compared to the upstream samples. Tetra- and trichlorobiphenyls accounted for 84 and 88% of the total residues measured in the downstream and tributary locations, respectively. In contrast, heptachlorobiphenyls were the prevailing homologues in sediments from the upstream sampling site, contributing 51% of the total PCB concentration. Predominant PCB homologues were: trichlorobiphenyl congener 28 and 37, tetrachlorobiphenyl congeners 44, 49, 52, 74, 77, and 81, andheptachlorobiphenyl congener 170. Sediment concentrations of DDE (19.7 ng/g dry weight) in the tributary, heptachlor epoxide (3.0 ng/g dry weight) in the downstream, and nickel (128-170 g/g dry weight) in all locations exceeded Probable Effect Levels (PELs) established for sediment quality in fresh water, indicating probable environmental stress and the potential for adverse effects to benthic organisms in the Dniester River. © 2005 Springer Science+Business Media, Inc. 1673 Impact of highly basic solutions on sorption of Cs+ to subsurface sediments from the Hanford site, USA Ainsworth C.C., Zachara J.M., Wagnon K. et al. Geochimica et Cosmochimica Acta 2005 69/20 (4787-4800) The effect of caustic NaNO3 solutions on the sorption of 137 Cs to a Hanford site micaceous subsurface sediment was investigated as a function of base exposure time (up to 168 d), temperature (10°C or 50°C), and NaOH concentration (0.1 mol/L to 3 mol/L). At 10°C and 0.1 M NaOH, the slow evolution of [Al]aq was in stark contrast to the rapid increase and subsequent loss of [Al]aq observed at 50°C (regardless of base concentration). Exposure to 0.1 M NaOH at 10°C for up to 168 d exhibited little if any measurable effect on sediment mineralogy, Cs+ sorption, or Cs+ selectivity; sorption was well described with a twosite ion exchange model modified to include enthalpy effects. At 50°C, dissolution of phyllosilicate minerals increased with [OH]. A zeolite (tetranatrolite; Na2 Al2 Si3 O10 2H2 O) precipitated in 0.1 M NaOH after about 7 days, while an unnamed mineral phase (Na14 Al12 Si13 O51 6H2 O) precipitated after 4 and 2 days of exposure to 1 M and 3 M NaOH solutions, respectively. Short-term (16 h) Cs+ sorption isotherms (10-9 -10-2 mol/ L) were measured on sediment after exposure to 0.1 M NaOH for 56, 112, and 168 days at 50°C. There was a trend toward slightly lower conditional equilibrium exchange constants ( log Na Cs Kc 0.25) over the entire range of surface coverage, and a slight loss of high affinity sites (15%) after 168 days of pretreatment with 0.1 M base solution. Cs+ sorption to sediment over longer times was also measured at 50°C in the presence of NaOH (0.1 M, 1 M, and 3 M NaOH) at Cs+ concentrations selected to probe a range of adsorption densities. Model simulations of Cs+ sorption to the sediment in the presence of 0.1 M NaOH for 112 days slightly under-predicted sorption at the lower Cs+ adsorption densities. At the higher adsorption densities, model simulations under-predicted sorption by 57%. This under-prediction was surmised to be the result of tetranatrolite precipitation, and subsequent slow Na ! Cs exchange. At higher OH concentrations, Cs+ sorption in the presence of base for 112 days was unexpectedly equal to, or greater than that expected for pristine sediment. The precipi- SEDIMENTOLOGY tation of secondary phases, coupled with the fairly unique mica distribution and quantity across all size-fractions in the Hanford sediment, appears to mitigate the impact of base dissolution on Cs+ sorption. Copyright © 2005 Elsevier Ltd. 1674 Trace metal distribution and enrichment in benthic, estuarine sediments: Southport Broadwater, Australia Burton E.D., Phillips I.R. and Hawker D.W. Environmental Geochemistry and Health 2005 27/5-6 (369-383) The distribution and enrichment of selected trace metals (Cd, Cr, Cu, Ni, Pb, Sn, Zn) in benthic sediments of the Southport Broadwater, a semi-enclosed coastal body of water adjacent to the Gold Coast city, south-eastern Queensland, Australia, was studied with the objective of assessing the extent and degree of sediment contamination. Sediment samples from the 0-10 cm and 10-20 cm depth intervals of 32 sites within the Southport Broadwater and surrounding residential canals were analysed for particle size distribution, pH, organic C and ‘near-total’ major (Al, Ca, Fe, Mn) and trace (Cd, Cr, Cu, Ni, Pb, Sn, Zn) metal contents. Sediment contamination for each trace metal was assessed by (1) comparison with Australian sediment quality guidelines, (2) calculation of the index of geoaccumulation based on regional background values, and (3) geochemical normalisation against Al (i.e. the abundance of alumino-silicate clay minerals). Based on this approach, the results indicate that submerged sediments in the study area are not presently enriched with Cd, Cr or Ni, with the spatial distribution of these metals being very well explained by the abundance of alumino-silicate clay minerals. However, several sites were strongly enriched with Cu, Pb, Sn and Zn, arising from sources related to either urban runoff or vessel maintenance activities. The study indicates that several varying approaches are needed for a satisfactory assessment of contaminant enrichment in estuarine sediments. © Springer 2005. 1675 Seasonal variations of racte metal chemical forms in bed sediments of a karstic river in Lebanon: Implications for self-purification Korfali S.I. and Davies B.E. Environmental Geochemistry and Health 2005 27/5-6 (385-395) Although Lebanon has abundant water, its rivers are polluted and aquifer water mismanaged. Effective river water usage requires an understanding of the geochemistry of polluting metals in catchments. Climate is "Mediterranean": Wet winters and dry summers. Active sediment flushing is restricted to winter high discharge episodes. Except in winter, water column pollutants are removed by precipitation or sorption to the surface of static bed sediments. Hence (1) does winter flushing of contaminated sediment and replacement by clean sediment favour self purification? (2) does the distribution of metals between extractable fractions change seasonally and thereby affect metal bioavailability? Results on the distribution of metals are reported for Fe, Pb, Zn, Cu and Cd in bed sediments from Nahr Ibrahim (a karstic river) for summer and winter. A Tessier-like sequential extraction scheme was applied to samples (< 75 m) for five locations along a 13 km stretch to the sea. Water pH was above 8.2 at all locations implying a very low solubility for Fe. Sediment was derived from catchment soils and limestone. Total sediment Fe increased in winter at all sites following deposition of eroded soil from upstream. Cadmium, Cu and Pb derived from polluting sources; the sources of Zn were more complex. Dilution by clean sediment explained winter reductions in total Cd, Cu and Pb; Zn changes were less consistent. Iron occurred mostly (> 77% sum of fractions) in the residual fraction compared with 6-31% for pollutants; residual Cu and Zn showed a small increase in winter whereas Cd and Pb did not change. All readily exchangeable metals decreased in winter and the carbonate bound forms predominated in both seasons. Nahr Ibrahim has a high capacity for self purification and metal resolubilisation from sediment will be limited by the solubility of carbonate forms. © Springer 2005. 1676 Geochemical distribution and bioavailability of heavy metals and oxalate in street sediments from Rio de Janeiro, Brazil: A preliminary investigation McAlister J.J., Smith B.J., Neto J.B. and Simpson J.K. Environmental Geochemistry and Health 2005 27/5-6 (429-441) As urbanisation accelerates within less-economically developed countries, populations in cities such as Rio de Janeiro are sub- 319 ject to numerous health risks relating to "heavy metal", sewage and vehicle pollution. These risks apply especially to children, through inhalation and dermal contact with pollutant-rich street sediments that reflect contamination from atmospheric deposition and act as effective sinks for heavy metals and oxalates. To assess the nature and extent of these risks street sediments were collected from industrial, commercial, residential and recreational areas with varying traffic densities within Rio de Janeiro. A modified selective extraction procedure was used to study the geochemical partitioning and bioavailability of Fe, Mn, Zn, Cu, Cr, Ni, Pb and C2 O-4 . Oxalate partitioning has not been studied by traditional sequential methods and results from this procedure highlight the potential bioavailability of both oxalates and "heavy metals", especially Pb and C2 O-4 in industrial and recreational areas. © Springer 2005. 1677 Transformation of arsenic compounds in modern intertidal sediments of Iriomote Island, Japan Masuda H., Yamatani Y. and Okai M. Journal of Geochemical Exploration 2005 87/2 (73-81) The arsenic accumulation process in intertidal sediments of Iriomote Island, Japan, is analyzed as a naturally balanced arsenicfixation system. Major and minor element chemistry is analyzed by X-ray fluorescence photometry, mineralogy is investigated by X-ray diffractometry, and four arsenic compounds are characterized by hydrogen-generated atomic absorption photometry. It is found that arsenic is accumulated by iron hydroxides/oxides precipitated following the decomposition of humic acids in the shallower sediment, and is subsequently incorporated into iron sulfide minerals at depth. The arsenic is immobile during incorporation into arsenic-bearing phases, suggesting that arsenic is unlikely to be released into the porewater under natural conditions in early diagenesis. The formation and decomposition of arsenicbearing organic compounds appear to be associated with the formation and decomposition of arsenic in oxyhydroxides/oxides, suggesting that microbial activity may play an important role in controlling the behavior of arsenic and arsenic-bearing phases in the sediment column. © 2005 Elsevier B.V. All rights reserved. 1678 Preliminary magnetic studies of lagoon and stream ´ Area (Argentina) - Magnetic pasediments from Chascomus rameters as indicators of heavy metal pollution and some results of using an experimental method to separate magnetic phases Chaparro M.A.E., Lirio J.M., Nu˜nez H. et al. Environmental Geology 2005 49/1 (30-43) Magnetic properties of lagoon and stream sediments from Chascom´us area (Buenos Aires Province) and the relevance of various magnetic parameters as giving pollution status are studied in the present work. This work is focussed on magnetic parameters, such as concentration-dependent (magnetic susceptibility, saturation anhysteric and isothermal remanent magnetisation) and feature-dependent parameters (S-ratio, coercivity of remanence, anhysteric susceptibility/magnetic susceptibility-ratio), as pollution indicators. Firstly and most importantly, different magnetic parameters and chemical measurements were correlated in order to investigate their goodness, obtaining the best results for feature-dependent magnetic parameters. Coercivity of remanence correlate very well with chemical variables, showing correlations at high level of significance up to 0.9094, and the anhysteric susceptibility/magnetic susceptibility-ratio also shows very good correlations (up to 0.8376). Some results and advantages of using a new experimental method in order to discriminate hard and soft magnetic phases are also shown. This method uses alternately backfield isothermal remanent magnetisation and alternating field demagnetisation. From the experimental separation, the presence of hard magnetic phases in some samples was confirmed. © Springer-Verlag 2005. 1679 The influence of fly and bottom ash deposition on the quality of Kastela Bay sediments Orescanin V., Barisic D., Lovrencic I. et al. Environmental Geology 2005 49/1 (53-64) The objective of this study was chemical and radiological characterization of Kastela Bay sediments exposed to numerous anthropogenic sources like deposition of fly and bottom ash enriched 320 SOILS in radionuclides and heavy metals, chemical plant, cement plant, iron plant, shipyard, electroplating facility, untreated industrial and domestic waste waters as well as heavy traffic. Totally, 33 samples of the mixture of fly and bottom ash, 12 sediment cores ranging from 0 to 40 cm and nine surface sediment samples were analyzed. Enrichment in heavy metals in the mixture of fly and bottom ash was ranging from 1.5 to 36 times compared to flysch soil while 226 Ra and 238 U were up to 50 times enriched compared to average activities characteristic for surrounding soils developed on the Middle and Upper Eocene flysch. Maximum 238 U activity was approximately 32 times higher and 226 Ra approximately 40 times higher in the Kastela Bay sediment compared to mean value determined for Adriatic sediments. The highest enrichment in sediment cores compared to background values were found for Zn (35.6 times), Pb (16 times), Cr (9.1 times) and Ni (4 times) © Springer-Verlag 2005. (GSUE) project was initiated in 1992 and to date, 21 cities have been mapped. Urban sampling is based upon the collection of top (0.05 to 0.20 m) and deeper (0.35 to 0.50 m) soil samples on a 500 m grid across the built environment (one sample per 0.25 km2 ). Samples are analysed for c. 46 total element concentrations by X-ray fluorescence spectrometry, pH and loss on ignition as an indicator of organic matter content. The data provide an overview of the urban geochemical signature and because they are collected as part of a national baseline programme, can be readily compared with soils in the rural hinterland to assess the extent of urban contamination. The data are of direct relevance to current UK land use planning, urban regeneration and contaminated land legislative regimes. An overview of the project and applications of the data to human health risk assessment, water quality protection and contaminant source identification are presented. © 2005 AAG/ Geological Society of London. 1680 Impact of human activity on the estuary of the Qiantang River and the reclamation of tidal flats and river regulation Feng L.- H. and Bao Y.- X. Environmental Geology 2005 49/1 (76-81) The swing of the main channel of the Qiantang River is controlled by the high-water and low-water changes in the river, as well as the impact of large-scale reclamation of tidal flats. Its evolution in modern times is the result of the combined functions of natural and man-made factors. This paper analyzes the cause of the formation of the South Channel and Xisan Tidal Furrow and proposes the regulation principle of "To regulate the river and reclaim tidal flats by taking the advantage of local topography". It is suggested to cut off the South Channel and Xisan Tidal Furrow completely to restrict the swing of the main channel and to increase the reclamation area of the tidal flat at the same time. © Springer-Verlag 2005. 1683 G-BASE: Baseline geochemical mapping of Great Britain and Northern Ireland Johnson C.C., Breward N., Ander E.L. and Ault L. Geochemistry: Exploration, Environment, Analysis 2005 5/4 (347-357) The Geochemical Baseline Survey of the Environment is a longestablished, high-resolution regional geochemical mapping project run by the British Geological Survey. A project initially stimulated by mineral exploration and to assist geological mapping has successfully evolved into a survey that has many environmental applications. Much of the current demand for surface geochemical data is driven by legislation. The geochemical mapping, originally based on the collection of drainage samples, has expanded to include soils and a further suite of determinands in stream waters. The methodology of the project and application of the baseline data are described and issues common to worldwide geochemical mapping programmes are discussed. © 2005 AAG/ Geological Society of London. SOILS Regional and survey 1681 Sub-continental-scale geochemical mapping: Sampling, quality control and data analysis issues Reimann C. Geochemistry: Exploration, Environment, Analysis 2005 5/4 (311-323) During 1996/97, c. 1500 samples of agricultural soils from ten northern European countries (western Belarus, Estonia, Finland, northern Germany, Latvia, Lithuania, Norway, Poland, northwestern Russia and Sweden) were collected from the Ap and B/C-horizons at 750 sites. The sample sites were evenly spread over a 1 800 000 km2 area, giving an average sample density of one site per 2500 km2 . The <2 mm fractions (Poland: <1 mm) of all samples were analysed for up to 62 chemical elements following ammonium acetate, aqua regia and HF extractions, and for total element concentrations by X-ray fluorescence spectrometry. Electrical conductivity, pH (water extraction) and loss on ignition (1030°C) were also determined. Each method was applied to all the samples in one laboratory only. The analytical results were evaluated and mapped using exploratory data analysis techniques. Even at this low sample density, regional-scale geochemical patterns emerge for all elements. These patterns show the influence of factors such as geology, agriculture, pollution, topography, marine aerosols and climate, and their relative importance for the observed element concentrations in the soils. Low-density geochemical mapping of agricultural soils is a viable tool to study the geochemical processes that determine the element distribution in soils at a sub-continental scale. © 2005 AAG/ Geological Society of London. 1682 GSUE: Urban geochemical mapping in Great Britain Fordyce F.M., Brown S.E., Ander E.L. et al. Geochemistry: Exploration, Environment, Analysis 2005 5/4 (325-336) The British Geological Survey is responsible for the national strategic geochemical survey of Great Britain. As part of this programme, the Geochemical Surveys of Urban Environments 1684 Geochemical mapping at the Geological Survey of Sweden Lax K. and Selinus O. Geochemistry: Exploration, Environment, Analysis 2005 5/4 (337-346) Geochemical mapping has been carried out for several decades at the Geological Survey of Sweden (SGU). Two kinds of sampling media dominate: glacial till (soil geochemical programme) and aquatic vegetation (biogeochemical mapping). Data from these mapping programmes have been used for various applications such as discoveries of contaminated land and research in environmental, medical and mineral exploration. The main goal of the geochemical mapping programmes has been to produce consistent and high quality data. Therefore, both programmes have been subject to various changes to increase their usefulness for decision-makers and planners. The number of parameters determined has increased, partial leach analysis has migrated from a combination of AAS/ ICP-AES techniques to ICP-MS, urban geochemistry projects have been incorporated, and additional terrestrial sediments have been added to the regional soil geochemical survey. An increasing number of new applications have also been implemented for emerging societal needs. This paper gives an overview of the mapping programme and examples of products for use in society as well as strategies for the future. © 2005 AAG/ Geological Society of London. 1685 Dynamic changes of soil ecological factors in Ziwuling secondary forest area under human disturbance (Chinese) Zhou Z. and Shangguan Z. Chinese Journal of Applied Ecology 2005 16/9 (1586-1590) As a widespread natural phenomenon, disturbance is considered as a discrete event occurred in natural ecosystems at various spatial and temporal scales. The occurrence of disturbance directly affects the structure, function and dynamics of ecosystems. Forest logging and forestland assart, the common human disturbances in forest area, have caused the dynamic changes of forest soil ecological factors in a relatively consistent environment. A study on the dynamics of soil bulk density, soil organic matter, soil microbes and other soil ecological factors under different human disturbance (logging and assart, logging but without assart, control) were conducted in the Ziwuling secondary forest area. The results indicated that human disturbance had a deep impact on the soil ecological factors, with soil physical and chemical SOILS properties become bad, soil organic matter decreased from 2.2% to 0.8%, and soil stable aggregates dropped more than 30%. The quantity of soil microbes decreased sharply with enhanced human disturbance. Soil organic matter and soil microbes decreased more than 50% and 90%, respectively, and soil bulk density increased from 0.9 to 1.21 gcm-3 with increasing soil depth. Ditch edge level also affected the dynamics of soil factors under the same disturbance, with a better soil ecological condition at low-than at high ditch edge level. Methods 1686 Development and evaluation of a simplified mechanistic-stochastic method for field-scale solute transport prediction Lee J. and Casey F.X.M. Soil Science 2005 170/4 (225-234) Field-scale solute transport is extremely complex due to the variability of soil properties. In this paper, a mechanistic-stochastic procedure for predicting field-scale solute transport was developed and evaluated. The mechanistic-stochastic method was based on a stream-tube model, which makes predictions using field estimates of shallow soil mobile water contents (m ) determined with a multiport permeameter. This procedure was evaluated for its ability to predict solute transport in a field soil. A field leaching experiment was conducted using fluorinated benzoic acid tracers that were applied to the surface at 12 plots in a field under pivot irrigation. Soil cores were taken to 1.5m depth at 1, 8, 18, and 36 days after initial tracer application to determine tracer redistribution. The mechanistic- stochastic method was compared with the observed data and against another stochastic method, a transfer function model (TFM), to evaluate its ability to predict solute redistribution for each sampling date. The proposed method had satisfactory predictions of the mean solute concentration redistributions from the leaching experiment and compared well against the predictions made by the TFM. The coefficients of determination ranged from 0.57 to 0.92 for the mechanistic-stochastic method and 0.29 to 0.99 for the TFM. The mechanistic-stochastic method can be greatly simplified, making it practical and desirable over the TFM, which required extensive subsoil leaching data for its calibration. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1687 Influence of soil moisture on near-infrared reflectance spectroscopic measurement of soil properties Chang C.- W., Laird D.A. and Hurburgh Jr. C.R. Soil Science 2005 170/4 (244-255) Near-infrared reflectance spectroscopy (NIRS), a nondestructive analytical technique, may someday be used to rapidly and simultaneously quantify several soil properties in agricultural fields. The objectives of this study were to examine the influence of moisture content on the accuracy of NIRS analysis of soil properties and to assess the robustness of a NIRS multivariate calibration technique. Four hundred agricultural soil samples (<2 mm) from Iowa and Minnesota were studied at two moisture levels: moist and air-dried. The soil properties tested included total C, organic C, inorganic C, total N, CEC, pH, texture, moisture, and potentially mineralizable N. About 70% of the Iowa samples were selected for the calibration set, and the rest of the Iowa samples and all of the Minnesota samples were assigned to validation set I and validation set II, respectively. Calibrations were based on partial least-squares regression (PLSR), using the first differentials of log (1/R) for the 1100 to 2500-nm spectral range. The results for the calibration set and validation set I indicated that NIRS-PLSR was able to predict many soil properties (total C, organic C, inorganic C, total N, CEC, % clay, and moisture) with reasonable accuracy for both the air-dried (R2 > 0.76) and moist (R2 > 0.74) soils. The results for validation set II showed that NIRS-PLSR was able to predict some properties of soils (total C, organic C, total N, and moisture content) from a different geographic region, but other soil properties in validation set II were not accurately predicted. Although NIRS-PLSR predictions are slightly more accurate for air-dried soils than for moist soils, the results indicate that the NIRS-PLSR technique can be used for analysis of field moist samples with acceptable accuracy as long as diverse soil samples from the same region are included in the 321 calibration database. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1688 A new in situ method to analyze mineral particle reactions in soils Birkefeld A., Schulin R. and Nowack B. Environmental Science and Technology 2005 39/9 (3302-3307) We developed a simple method to monitorthe transformation of particles in soils under in situ conditions. The particles were fixed on small polymer supports (2 cm x 2 cm) with a thin film of epoxy resin. Attached to these carriers, the particles could be put into close contact with soil at a chosen site and easily recovered after extended periods of time. The method was tested with lead oxide and copper concentrate in the field. Quartz and copper oxide particles were used in preliminary laboratory experiments. The used particles sizes ranged from 20 to 200 m. Laboratory and field experiments with acidic and calcareous soils showed that the PbO and Cu concentrate coated polymer supports were stable under field conditions for at least one year. Nondestructive X-ray fluorescence spectroscopy was used to quantify the metals before and after exposure. Scanning electron microscopy combined with energy-dispersive X-ray spectroscopy as well as micro-Raman spectroscopy was used to identify signs of dissolution and newly formed mineral phases. The mineral dissolution rate could be determined under field conditions. The new method has the potential to be used in other environmental media such as sediments or water to study the reactions of a variety of particles larger than 20 m. © 2005 American Chemical Society. 1689 Soil water estimation using electromagnetic induction Akbar M.A., Kenimer A.L., Searcy S.W. and Torbert H.A. Transactions of the American Society of Agricultural Engineers 2005 48/1 (129-135) Two published salinity models (designated the Rhoades and Mualem-Friedman models, respectively) were examined for application to real-time soil water estimation using apparent soil electrical conductivity. Field data were collected at two sites representing a range of soil types in central Texas: high shrinking-swelling Vertisols in Temple (the Heiden Clay site) and clay loam soils at the Texas A&M University Research Farm near College Station (the Westwood Scl site). The Rhoades-Corwin model developed for the Heiden Clay site yielded an R2 of 0.72 following calibration, predicted soil water within 0.02 g g-1 during validation, and was deemed generally applicable for real-time soil water estimation. The Rhoades-Corwin model developed for the Westwood Scl site gave an R2 of 0.65 following calibration but could not be validated at the site and therefore was not considered applicable for real-time soil water estimation. A modified version of the Rhoades-Corwin model yielded a calibrated R2 of 0.91 at the Westwood Scl site with validation predictions within 0.02 g g -1 . The Mualem-Friedman model predicted soil water within 0.05 g g-1 at the Heiden Clay site and was considered appropriate for real-time soil water estimation. At the Westwood Scl site, the Mualem-Friedman model could not be evaluated since saturation data were not available. Both models show promise for use for real-time, non-invasive soil water content estimation using apparent electrical conductivity, but additional testing is needed. 1690 Comparison of three extraction methods for 17 -estradiol in sand, bentonite, and organic-rich silt loam Chun S., Lee J., Geyer R. and White D.C. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/5 (731-740) Extraction is an important procedure for samples that contain soil because other compounds in soil may affect analysis of estrogens. This study was conducted to evaluate three different extraction methods for 17 -estradiol in soil. Sand, bentonite, and organicrich silt loam were spiked with 1 mg kg-1 of 17 -estradiol as a model compound of estrogens. 17 -estradiol and its metabolites, estrone and estriol, were extracted using (i) a modified Bligh and Dyer extraction, (ii) a pressurized fluid extraction, and (iii) a diethyl ether extraction, and measured by liquid chromatography tandem mass spectrometry. There were significant differences in the extraction efficiency for 17 -estradiol among the extraction methods and the soils: the efficiencies ranged from 10% to 97%. 322 SOILS Overall, the diethyl ether extraction method had the largest efficiency of 17 -estradiol with 45% and 57% for bentonite and silt loam, respectively. Transformation of 17 -estradiol to estrone and estriol in the different extraction methods was less than 3.6% during the extraction procedures. This study underlined the importance of sample preparation for estrogen analysis in soil samples. Copyright © Taylor & Francis Inc. 1691 Effect of agricultural antibiotics on the persistence and transformation of 17 -estradiol in a Sequatchie loam Chun S., Lee J., Geyer R. et al. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/5 (741-751) A laboratory incubation study was conducted to investigate the effect of agricultural antibiotics (sulfamethazine, tylosin, and chlortetracycline) on the persistence and transformation of 17 estradiol in Sequatchie loam. We measured concentrations of 17 -estradiol and its primary metabolite (estrone) in soils spiked with antibiotics and 17 -estradiol. Dehydrogenase activity (DHA) was also measured as an indicator of the total microbial activity of the soils. The presence of antibiotics significantly decreased transformation of 17 -estradiol to estrone. There was a positive correlation between the DHA and the concentrations of estrone in soil spiked with 17 -estradiol only, implying that the reaction is mainly catalyzed by dehydrogenases. However, the positive correlation was weakened in soil spiked with 17 estradiol and antibiotics together. We recommend that any study evaluating the fate and transport of estrogenic hormones in soil should include the effect of agricultural antibiotics because antibiotics and estrogenic hormones are commonly excreted together in environmental samples. Copyright © Taylor & Francis Inc. 1692 Soil identification and chemometrics for direct determination of nitrate in soils using FTIR-ATR mid-infrared spectroscopy Linker R., Shmulevich I., Kenny A. and Shaviv A. Chemosphere 2005 61/5 (652-658) The use of mid-infrared attenuated total reflectance (ATR) spectroscopy enables direct measurement of nitrate concentration in soil pastes, but strong interfering absorbance bands due to water and soil constituents limit the accuracy of straightforward determination. Accurate subtraction of the water spectrum improves the correlation between nitrate concentration and its 3 vibration band around 1350 cm-1 . However, this correlation is soil-dependent, due mostly to varying contents of carbonate, whose absorbance band overlaps the nitrate band. In the present work, a two-stage method is developed: First, the soil type is identified by comparing the "fingerprint" region of the spectrum (800-1200 cm-1 ) to a reference spectral library. In the second stage, nitrate concentration is estimated using the spectrum interval that includes the nitrate band, together with the soil type previously identified. Three methods are compared for estimating nitrate concentration: integration of the nitrate absorbance band, cross-correlation with a reference spectrum, and principal component analysis (PCA) followed by a neural network. When using simple band integration, the use of soil specific calibration curves leads to determination errors ranging from 5.5 to 24 mg[N]/kg[dry soil] for the mineral soils tested. The cross-correlation technique leads to similar results. The combination of soil identification with PCA and neural network modeling improves the predictions, especially for soils containing calcium carbonate. Typical prediction errors for light non-calcareous soils are about 4 mg[N]/kg[dry soil], whereas for soils containing calcium carbonate they range from 6 to 20 mg[N]/kg[dry soil], which is less than four percent of the concentration range investigated. © 2005 Elsevier Ltd. All rights reserved. 1693 Modification and application of a soil ATP determination method Wen G., Voroney R.P., Curtin D. et al. Soil Biology and Biochemistry 2005 37/11 (1999-2006) Accurate estimation of microbial adenosine 5 -triphosphate (ATP) is a pre-requisite to quantify the impact of varying environments on microbial activity of soil. We investigated the effectiveness of a high efficiency soil ATP determination method (PA) [Webster, J.J., Hampton, G.J., Leach, F.R., 1984. ATP in soil: a new extractant and extraction procedure. Soil Biology & Biochemistry 4, 335-342] in 10 Ontario (Canada) soils collected along a 100 m transect and spanning a textural class gradient ranging from a sandy loam to clay loam with increasing organic matter. Modifications of the method involved using an extract of autoclaved soil to make the standard curve, as it was found that the light emitted by ATP luciferin-luciferase bioluminescence reaction in the pure extractant was different from that in the extracts. Replacing Tricine with Tris buffer in the assay significantly improved the light emission. On an average, the internal standard calibration method (ISM) measured a smaller amount of extracted ATP (1199 ng ATP g-1 soil) and a lower recovery of ATP spike (82.4 7.2%) than did the standard curve method (SCM) (1246 ng ATP g-1 soil and 91.2 4.5%, respectively) (P<0.05 for both comparisons). However, the average total estimated ATP was higher with ISM (1474 102 ng ATP g-1 soil) than with SCM (1373 88 ng ATP g-1 soil) (P<0.07). While the recovery rates determined using SCM were consistent among the soils tested, the rates measured using ISM was negatively correlated with soil clay and organic matter content, implying that the latter assay was affected by the soil properties. Our results confirmed that the recovery rates obtained by the PA method were the highest among those reported, when only SCM was used. © 2005 Elsevier Ltd. All rights reserved. 1694 Nematodes as bioindicator of soil health: Methods and applications (Chinese) Li Y., Wu J., Chen H. and Chen J. Chinese Journal of Applied Ecology 2005 16/8 (1541-1546) This paper summarized the advantages of using nematodes as soil health bioindicator. A review of commonly used indices and analyzing methods by means of nematodes was presented, with emphases on Maturity Index, as well as the indices and analyzing methods based on their trophic groups. Compared with other indices, Maturity Index can reflect the stressed degree of soil more sensitively, and the indices and analyzing methods based on their trophic groups can well reveal the state of soil health based on ecosystem functioning. The applications of nematodes as bioindicator in agriculture, forest, grassland, and other ecosystems were also outlined. In view of some practical limitations in the methods, prospective researches and applications were suggested, i.e., intensify the ecological studies to advance the understanding on the characteristics of soil nematodes, such as their life histories and feeding habits, consummate the indication system by integrating various nematode indices and analyzing methods, and extend the applications of soil nematodes in different ecosystems and in different regions at large scales. Genesis and formation 1695 The role of fire and nutrient loss in the genesis of the forest soils of Tasmania and southern New Zealand McIntosh P.D., Laffan M.D. and Hewitt A.E. Forest Ecology and Management 2005 220/1-3 (185-215) The dominant soil patterns in forested or previously forested landscapes in southern New Zealand and Tasmania are described. Soil properties on adjacent sunny and shady aspects in hill country of the South Island of New Zealand are compared to soil properties under adjacent ‘dry’ and ‘wet’ eucalypt forest in Tasmania. A soil contrast index or SCI is defined for comparing soil contrasts on parent materials of different absolute nutrient contents. Three soil groups are defined using the SCI. Group 1 soil pairs are stable New Zealand soils in which exchangeable Ca + Mg + K values are higher on drier sunny aspects than on moister shady aspects. Group 2 soil pairs are New Zealand soils in which soils on sunny aspects display evidence of topsoil erosion by wind; consequently some soil pairs on dry (sunny) aspects have lower levels of exchangeable Ca + Mg + K than soils on moister (shady) aspects. Group 3 soil pairs are Tasmanian. Soils on drier sites (under dry eucalypt forest) invariably have lower exchangeable Ca + Mg + K values than soils on moister sites (under wet eucalypt forest), which is the reverse of the pattern in SCI Group 1 soils in New Zealand. Except on clay-rich parent materials, Tasmanian soils under dry forest generally have texture-contrast profiles and a mean C/N ratio in topsoils (A1 horizons) of 29. Soils under SOILS wet forest generally have uniform or gradational texture profiles and a mean topsoil C/N ratio of 15. The texture-contrast soils show strong clay eluviation with sand or sandy loam textures in upper horizons and clayey textures in lower horizons. However, in New Zealand texture-contrast soils are all but absent, and do not occur in the previously forested areas described in this paper. Topsoils (Ah horizons and soils sampled to 7.5 cm depth) in New Zealand areas sampled in this study have a mean C/N ratio of 15, regardless of whether they occur on sunny or shady aspects. We propose that the frequency and spatial occurrence of fire are the dominant processes causing: (1) the marked difference in levels of nutrients and different topsoil C/N ratios in soils of Tasmania; (2) the development of texture-contrast soils under dry forests in Tasmania; and (3) the difference between soil patterns in New Zealand and Tasmania. Fire depletes nutrients in forests by causing losses to the atmosphere, losses by runoff, and losses by leaching. Nutrient loss by fire encourages fire-tolerant vegetation adapted to lower soil nutrient status, so frequent fire is a feedback mechanism that causes progressive soil nutrient depletion. By destroying organic matter and diminishing organic matter supply to the soil surface fire inhibits clay-organic matter linkages and soil faunal mixing and promotes clay eluviation. Fire frequency is likely to have increased markedly with the arrival of humans at ca. 34 000 years B.P. in Tasmania and ca. 800 years B.P. in New Zealand. We argue that texture-contrast soils have not formed in New Zealand because of the short history of frequent fires in that country. A corollary of this conclusion is that texture-contrast soils in Tasmania are, at least in part, anthropogenic in origin. © 2005 Elsevier B.V. All rights reserved. 1696 Soils developed on volcanic materials in the island of Thera, Greece Moustakas N.K. and Georgoulias F. Geoderma 2005 129/3-4 (125-138) Samples were taken of soils formed on volcanic material, primarily composed of rhyodacitic pumice, on the island of Thera, Greece (South Aegean Sea, Southeastern Mediterranean), and analyses for physical and chemical properties carried out. These soils are characterised as having a coarse texture, low organic matter content, low cation exchange capacity (CEC) and soil moisture retention, but a high pH despite the acidic nature of the parent material. Extraction with sodium dithionite-citrate, acid ammonium oxalate, sodium pyrophosphate and hot 0.5 M NaOH showed that, in contrast to soils usually forming on volcanic material worldwide, soils lack noncrystalline minerals like allophane, imogolite, ferrihydrite and iron and aluminium humus complexes. The only noncrystalline mineral present and, in great quantities, is amorphous silica. Winds, prevailing practically all year round, transfer droplets of seawater to these soils which in combination with the great porosity, relatively high sodium content of the parent material and low rainfall are the primary factors in the poor development of these soils and high pH. No andic properties are apparent and, hence, these soils cannot be classified as Andisols. The major factors determining soil genesis on the island of Thera would appear to be the nature of the parent material and the climate. © 2004 Elsevier B.V. All rights reserved. 1697 Exploring pedogenesis via nuclide-based soil production rates and OSL-based bioturbation rates Wilkinson M.T. and Humphreys G.S. Australian Journal of Soil Research 2005 43/6 (767-779) New dating techniques are available for soil scientists to test fundamental pedogenic ideas. Recent developments in applications of terrestrial in situ cosmogenic nuclides (TCN) from bedrock and saprolite allow the derivation of soil production rates, at scales ranging from local (sub-hillslope) to catchment wide, generally averaged over timescales of 104 -105 years. Where soil depths are relatively constant over time, soil production rates equal transport rates and are thus essential to establishing sustainable erosion rates. TCN also allow the form of the soil production function to be compared to theoretical models - a difficult task previously. Furthermore, parameterised soil production functions can now be incorporated into numerical surface process models to test landscape evolution ideas. Bedrock and saprolite conversion to soil is demonstrably dependent on the overlying soil depth, and there is general agreement that weathering 323 declines exponentially beyond maximum soil production, consistent with theory. Whether maximum soil production occurs under a finite or non-existent soil cover at particular sites remains unresolved. We suggest that, in general, soil production from saprolite declines exponentially with increasing depth, while production from bedrock follows a humped function. Estimates of the role of flora, fauna and processes such as freeze-thaw that mix soil mantles to depth, have been limited prior to optically stimulated luminescence (OSL) dating techniques. Recently derived OSL mixing rates extend the magnitude of previous partial, short-term bioturbation rates. In fact, bioturbation appears to be the most active pedogenic process operating in many soils, with freeze-thaw environments a noted exception. Although bioturbation far outweighs soil production, it does not always lead to homogenisation as is often reported. We maintain that the aboveground component of bioturbation, i.e. mounding, may alone, or particularly when combined with particle sorting via rainwash processes, lead to horizonisation and texture contrast soils in those materials that can be sorted such as mixtures of sand and clay. Together, TCN- and OSL-based estimates of hillslope soil transport and bioturbation, suggest significant rates of downslope soil mantle movement coupled with rapid mixing, contrary to in situ soil development models. © CSIRO 2005. 1698 Formation and properties of aridic soils of Azraq Basin in northeastern Jordan Khresat S.A. and Qudah E.A. Journal of Arid Environments 2006 64/1 (116-136) Aridisols occupy a wide and significant part of Jordan. The majority of soils in the Azraq Basin, northeastern Jordan, are aridisols. A database on aridisols and land characteristics in northeastern Jordan is needed to allow rational planning of land and water resources utilization. The objectives of this paper are to: characterize the main soil types in the area, and identify the main processes contributing to their genesis and evolution. For this purpose eight representative profiles were selected for this study and soil samples were collected and their chemical and physical properties were examined in the laboratory. The natural vegetation is desert shrubs and short grasses. The sparseness of the vegetation resulted in low SOM content and the presence of ochric epipedons in all of the studied soils. The genesis of these soils accounts for the accumulation of calcium carbonate, soluble salts, and gypsum in the subsoil. Carbonate, clay eluviation-illuviation, and salt accumulation are the dominant pedogenic processes in these soils. Silt content increased toward the surface indicating eolian activity. Clay content increased with depth indicating illuviation of clay. Clay illuviation and argillic horizon development within these soils is assumed to be a relict feature from presumably more humid climates during the Quaternary. Desert pavements cover the surfaces of these soils and provide a unique obstacle for agricultural development. The major restrictions to agricultural land use in the area are very low infiltration rate, low permeability, and high erodibility. Proper management practices should be adopted if such soils are to be cultivated. © 2005 Elsevier Ltd. All rights reserved. 1699 Soil-landform development of a part of the fold belt along the eastern coast of Bangladesh Sharif Hossain Khan Md., Parkash B. and Kumar S. Geomorphology 2005 71/3-4 (310-327) The evolution of landforms and soils from the Jaldi and Maiskhali anticlines and adjoining areas in a part of the coastal region of the north-south trending fold belt of Bangladesh during the Late Quaternary Period has been investigated. Based on the degree of soil development and luminescence dating, eight soil geomorphic units have been deciphered and grouped into four members (I-IV) of a morphostratigraphic sequence for the study area. Various soil geomorphic units included in different member/sub-members are: Member I - river floodplains and active tidal flats (< 500 years); Member II - distal Piedmont Plains and old tidal flats (0.5-2 ka); Member III - proximal Piedmont Plains (6-10 ka); and Member IV - Mainland Higher and Lower Hillocks and Island Hillocks (> 15 ka). Member IV is further subdivided into Sub-member IVa - Island Hillocks (15-18 ka); Sub-member IVb - Mainland Lower Hillocks (23-25 ka); and Sub-member IVc - Mainland Higher Hillocks (30-35 ka). The youngest and poorly developed soils of Member I show features related to 324 SOILS hydromorphism. Moderately developed soils of Members II and III show a fersiallitisation stage of pedogenesis. Member IV includes ‘strongly developed soils’ with a ferrugination stage of pedogenesis. These soils also exhibit degradation and poor birefringence of argillans and ferriargillans, indicating a significant change in conditions of pedogenesis, probably related to a paleoclimatic change from a subhumid to semiarid phase (40 ka to about 16 ka) to a hot humid to subhumid phase (16 kapresent). Parent material composition and physiography also have affected the pedogenesis in the area. Based on ages and heights above the mean sea level for the five terraces recognized in the study area, the overall base-level rise rates calculated are about 3.6 mm/year (18 ka-present) for the Maiskhali Island and 2.86 mm/year (35 ka-present) for the mainland (Jaldi anticline). These base level changes represent combined effects of eustatic sea level and tectonic uplift due to folding. © 2005 Elsevier B.V. All rights reserved. Physical properties 1700 The effect of soil water content and microbial activity on restoring the structure of a Vertisol Kostopoulou S.K. and Zotos A. Soil and Tillage Research 2005 82/2 (203-209) Soils with high clay content are susceptible to structural damage, if they are intensively cultivated. The structure of soils of the Vertisol group has the tendency to restore as a result of wetting and drying. Samples of a remoulded clayey soil were exposed to seven successive wetting/drying (w/d) cycles, in order to study the change of some structural features of the newly formed aggregates. To assess the effect of soil water content and microbial activity, two different matric water potential ranges were used under sterile and non-sterile conditions. Aggregate size distribution depended on both the water potential range and microbial activity and approached to a steady state with increasing cycle number. The water stability of the 2-1 mm aggregates was affected by the activity of soil micro-organisms under wet conditions and by forces of mechanical nature when the soil was reaching dryness. All cases resulted in aggregates of reduced water stability with respect to the natural aggregates. The <50 m aggregated particles initially preserved stability, but after a number of w/d cycles they collapsed at a rate, depending mainly on the water potential range. © 2004 Elsevier B.V. All rights reserved. 1701 Andic soils of the Inland Pacific Northwest, USA: Properties and ecological significance McDaniel P.A., Wilson M.A., Burt R. et al. Soil Science 2005 170/4 (300-311) Holocene tephra from the cataclysmic eruption of Mount Mazama in southwestern Oregon is an important component of many soils east of Cascade Mountains in the Pacific Northwest region. This article examines ecologically important properties of these tephra-influenced soils. Characterization data from 886 soil horizons (384 pedons) of the region meeting criteria for andic soil properties or subgroup classification as andic or vitrandic intergrades in Soil Taxonomy were used to compare morphological, chemical, and physical properties. Mazama tephra typically comprises a significant portion of a surface mantle with textures ranging from silt loam in areas distal to the tephra source to very gravelly loamy coarse sand in proximal locations. Tephra has been mixed to varying degrees with other parent materials across the region. On average, volcanic glass only comprises 31.1% of the 0.05 to 2-mm fraction and has a bimodal distribution, suggesting that some tephra was deposited with significant quantities of dust or, that since deposition, considerable reworking and mixing of glass has occurred. Oxalate-extractable Al ranges from 0.04 to 5.4% and provides the best indicator of colloidal surface activity as indicated by P retention. Cation exchange capacity (CEC) determined at field pH (ECEC) averages 7.8 cmolc kg-1 and is less than one-third the CEC determined at pH 8.2, indicating considerable variable charge and relatively low capacity of these soils to store and supply nutrient cations. Mineralogical data suggest that a reduced pool of secondary Al may be limiting allophane formation in soil horizons with less tephra influence. Volumetric water-holding capacity of ash-influenced horizons is as much as twice that of underlying horizons and underscores the importance of tephra in seasonally dry, forested ecosystems of the Inland Northwest region. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1702 The fate of the recombinant DNA in corn during composting Guan J., Spencer J.L. and Ma B.- L. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/3 (463-473) In order to make regulations that safeguard food and the environment, an understanding of the fate of transgenes from genetically modified (GM) plants is of crucial importance. A compost experiment including mature transgenic corn plants and seeds of event Bt 176 (Zea mays L.) was conducted to trace the fate of the transgene cryIA(b) during the period of composting. In bin 1, shredded corn plants including seeds were composted above a layer of cow manure and samples from the corn layer were collected at intervals during a 12-month period. The samples were tested for the transgene persistence and microbial counts and also the compost was monitored for temperature. In bin 2, piles of corn seeds, surrounded by sheep manure and straw, were composted for 12 months. A method combining nested polymerase chain reaction (PCR) and southern hybridization was developed for detection of the transgene in compost. The detection sensitivity was 200 copies of the transgene per gram of dry composted corn material. Composting commenced on day 0, and the transgene was detected in specimens from bin 1 on days 0 and 7 but not on day 14 or thereafter. The transgene in corn seeds was not detectable after 12 months of composting in bin 2. Temperatures in both bins rose to about 50°C within 2 weeks and remained above that temperature for about 3 months, even when the ambient temperature dropped below -20°C. Extracts from compost were inoculated onto culture plates and then were incubated at 23 to 55°C. Within the first 2 weeks of composting in bin 1, the counts of bacteria incubated at 55°C increased from 3.5 to 7.5 log10 , whereas those incubated at 23°C remained at about 7.5 log10 . The counts of fungi incubated at 45°C increased slightly from 2.5 to 3.1 log10 , but those incubated at 23°C decreased from 6.3 to 3.0 log10 . The rapid degradation of the transgene during composting of Bt corn plants suggested that the composting process could be used for safe disposal of transgenic plant wastes. 1703 Traditional and new deep soil tillage techniques in Italy Pezzi F. Transactions of the American Society of Agricultural Engineers 2005 48/1 (13-17) A study evaluated the performance of traditional and alternative implements for deep tillage. Three implements were compared, a plow and two PTO-driven machines (spading machine and rotary chisel), along with two soil depths, 0.30 and 0.40 m, and two forward speeds. Tests were done on a level plot, containing silty-clay soil. Forward speed, wheel slip, fuel consumption, and energy at the PTO and drawbar were measured. Cloddiness of the tilled soil was evaluated. The two PTO-powered implements did not show advantages in terms of capacity, but they gave better results in fuel consumption and in soil pulverization. Economic evaluation showed lower unit costs (17% to 28%) for the spading machine. © 2005 American Society of Agricultural Engineers. 1704 Characterization of apparent soil electrical conductivity variability in irrigated sandy and non-saline fields in Colorado Farahani H.J., Buchleiter G.W. and Brodahl M.K. Transactions of the American Society of Agricultural Engineers 2005 48/1 (155-168) Recent advances in apparent soil electrical conductivity (ECa ) sensor technology have provided the opportunity to rapidly map soil spatial variability for site-specific management. However, characterizing (or identifying the causes of) the ECa variability has remained difficult, with ECa and soil property (such as soil water and clay content) relationships showing a wide range of varying strength across fields. In this study, our objective was to characterize the main soil properties that alter ECa and evaluate the temporal variability of ECa and soil property relationships SOILS using multi-year measurements (1998 to 2003) in three centerpivot irrigated fields in eastern Colorado. Results show that for the irrigated sandy and non-saline fields, ECa maps may be viewed as surrogate maps for soil water content (w ), clay, cation exchange capacity, and/or organic matter content due to their strong correlations (with correlation coefficients between 0.66 and 0.96). The experimental linear functions of ECa versus soil properties changed over time when soil solution concentration (ECw ) changed considerably. That finding was supported by theory (the dual-pathway EC a model) showing the relationship between ECa and soil stable properties (such as clay content) to be governed by the status of the soil transient properties of ECw and w at the time of the ECa mapping. The temporal effect of varying soil temperature on ECa could be significant but was not accounted for due to lack of temperature data. Results collectively suggest that because of the lack of reliability of using empirical ECa and soil property relationships for predictive purposes over time, on-site calibration of ECa versus soil properties of interest are needed at each ECa mapping. 1705 Freezing of subarctic hillslopes, Wolf Creek basin, Yukon, Canada Carey S.K. and Woo M.- K. Arctic, Antarctic, and Alpine Research 2005 37/1 (1-10) Freezing processes were monitored at five sites within the Wolf Creek basin, Yukon, Canada during the winter of 1998-1999. Ground temperatures were measured using thermocouples in hillslopes that had frost status ranging from permanent to seasonal. The timing of freezing and ground thermal regimes varied among the five sites and was controlled by (1) the variation in surface soil temperature, (2) frost status (seasonal vs. permanent), (3) moisture content of the active layer, (4) properties of the soil profile, and (5) the presence/absence of subsurface drainage. On slopes with permafrost, cooling was rapid and two-sided freezing closed the active layer several months after the onset of freezing. On a slope with seasonal frost only, dry soil conditions allowed frost to penetrate to depth. In contrast, a slope with seasonal frost that had continuous drainage, frost depths were shallow due to heat advected from flowing water. A simple one-dimensional conduction model with latent heat was used to simulate freezing processes. Model performance varied among the slopes, and results indicate that (1) conduction is the predominant heat transfer mechanism during freezing, (2) latent heat is the principal factor controlling frost front descent, and (3) lateral flow significantly retards frost penetration because of heat advection. This information is valuable in assessing spatial variability within tile-based models and in predicting freezing, which defines an effective end-of-season on lateral hydrological processes. © 2005 Regents of the University of Colorado. 1706 The effect of wildfire intensity on soil aggregate stability in the Cadiretes Massif, NE Spain ´ Ubeda X. and Bernia S. IAHS-AISH Publication 2005 -/299 (3745) This paper reports on the changes in soil aggregate stability after a wildfire, with the focus on the effects of fire intensity on soil structure. The aggregate stability of soils burned at different fire intensities was tested using the TDI method. The samples were taken from three areas burned at three fire intensities and the results of the aggregates were compared with those from an unburned forest. The study area is located in the Cadiretes massif, northeast Spain. The analyses were undertaken just after the fire in 1994, and again in 1995 and 1997. The most stable aggregates compared to those from the control area were those sampled just after the fire. The disaggregation was highest in 1995 and lowest in 1997. The fire did not disturb the stability of the aggregates immediately after burning. After the fire the aggregates did not become unstable and, in contrast, they were even more stable than those sampled in the control forest. 1707 Nearreal time variability of soil moisture and temperature under different land use and cover: The Alabama Mesonet Tsegaye T.D., Metzl R., Wang X. et al. Journal of Environmental Hydrology 2005 13/- (13p) The Alabama Mesonet (ALMNet) has been established to pro- 325 vide near-real-time data to conduct research that aims to ensure the security, quality, and quantity of the Nation’s natural resources. The ALMNet is made up of eleven combination meteorological/soil profile stations and twelve soil profile stations positioned at 23 locations in eight counties. The stations are included in the USDA NRCS SCAN network. Meteorological and soil profile data collected by ALMNet include temperature (air and soil), humidity, solar radiation, wind (speed and direction), soil heat flux, soil moisture and precipitation. The objectives of the ALMNet are to: (i) serve as a validation site for current and future satellite missions of monitoring soil moisture (e.g. the Aqua satellite) and archive both atmospheric and hydrologie related data: (ii) study soil moisture and temperature variability at different time scales and under different land use and land cover: (in) model soil water content and temperature from observable climate data and compare model estimates in terms of energy partitioning: (iv) strengthen outdoor research and training facilities for both undergraduate and graduate students: and (v) establish an Online Internet Service for extension agents, farmers and interested individuals to visualize climate related data. Our long-term vision is to complete detailed hydrological and meteorological process analyses for northern Alabama and southern Tennessee in collaboration with scientists from NASA, USDA and other Universities. We also hope to expand the recording sites throughout Alabama as our resources permit. 1708 Determining long-term effective groundwater recharge by analyzing vertical soil temperature profiles at meteorological stations Cheviron B., Gu´erin R., Tabbagh A. and Bendjoudi H. Water Resources Research 2005 41/9 (1-6) [1] Vertical water seepage in soils results in convective heat transport that modifies the temperature profiles and their variations with time; consequently, there is a relationship between temperature profile variations with time and the vertical Darcy velocity associated with the seepage. Considering the annual sinusoidal time variation of the temperature at the soil surface, it can be shown that convective heat transport has a significant effect on the amplitude damping with depth and a negligible effect on the phase lag with depth of the temperature time signal. Standard meteorological stations constitute a relatively dense network, and we show that their routinely collected data can be used to determine an average value of the vertical Darcy velocity, uZ , representing the effective annual recharge over long time periods (several years). A new procedure for determining uZ from these temperature records is presented. First, the layering of the medium is determined by an electrical sounding. Then the thermal properties of each layer are inferred from the phase lag with depth. Finally, uZ is calculated from the amplitude damping. After having tested this approach with synthetic data, we used the 1984-2001 Abbeville (Somme, France) data to determine the average recharge over six 3-year periods. The results are in good agreement with classical meteorological recharge estimates and show a significant increase in the recharge during the last 3year period, consistent with the observed phreatic 2001 flood event. Specific temperature measurements at appropriate depths and time steps could drastically improve the sensitivity of the method. Copyright 2005 by the American Geophysical Union. 1709 Influence of water regime and N availability on the emission of nitrous oxide and carbon dioxide from tropical, semi-arid soils of Chiapas, Mexico Ponce- Mendoza A., Boeckx P., Gutierrez- Miceli F. et al. Journal of Arid Environments 2006 64/1 (137-151) The concentration of nitrous oxide (N2 O) and carbon dioxide (CO2 ) in the atmosphere has increased considerably over the last century, but few studies are available showing their production from soils in semi-arid areas. Soils from the tropical semiarid Central Depression of Chiapas were sampled from fields cultivated with maize (MAI treatment), under canopy of Acacia angustissima (TIMBRE) or outside the canopy of the trees (OUT), adjusted to 40%, 60%, 80% or 100% of water-holding capacity (WHC) and amended with 0, 15 or 50 mg (NH4 NO3 )-N kg-1 dry soil. The production of N2 O, CO2 and concentrations of NH +4 , and NO-3 were monitored in the laboratory under aerobic conditions. Production of N2 O in the first 3 days was significantly larger from the MAI and OUT soils, compared to the TIMBRE 326 SOILS soil, while the addition of 50 mg inorganic N doubled the production of N2 O. In all treatments, soil at 100% WHC had the largest production of N2 O. The emission of CO2 was significantly larger from soils at 60% and 80% WHC compared to the soil at 40% and 100% WHC, although the addition of inorganic N had no significant effect on CO2 emission. The application of inorganic N and the absence of vegetation increased the production of N2 O. © 2005 Elsevier Ltd. All rights reserved. 1710 Quantitative characteristics of soil aggregates under different vegetations in upper reach of Minjiang River (Chinese) Ning L., Shi H., Zhou H. and Liu S. Chinese Journal of Applied Ecology 2005 16/8 (1405-1410) Quantitative analysis on the soil aggregates under dark coniferous forest, coniferous and broad-leaved mixed forest, fargesia under the gap of dark coniferous forest, and sclerophyllous oaks (Quercus semicarpifolia) at Wolong Natural Reserve in the upper reach of Minjiang River showed that wet-sieving soil aggregates were of logarithmic-normal distribution, and the geometric mean diameters were negatively correlated to geometric standard deviation. The aggregates under coniferous and broad-leaved mixed forest and sclerophyllous oaks had larger sizes than those under other vegetations. The range of fractal dimension of soil aggregates was 2.40-2.78, along with more aggregates less than 0.25 mm in size. The fractal dimension of soil aggregates under dark coniferous forest and fargesia were larger than that under other vegetations. The soil aggregates with 3-1 mm and 1-0.5 mm in size had a higher stability, while those with > 10 mm and 0.5-0.25 mm in size were in adverse. The aggregate stability index of soil under coniferous and broad-leaved mixed forest was the highest, followed by that under sclerophyllous oaks, fargesia under the gap of dark coniferous forest, and dark coniferous forest, which meant that coniferous and broadleaf mixed forest and sclerophyllous oaks were favorable for soil aggregate stability. Significant correlations were found among the three quantitative characteristics, which could be used to indicate the stability of soil aggregates. Soil water 1711 Preferential water flow in a glacial till soil Jansson C., Espeby B. and Jansson P.- E. Nordic Hydrology 2005 36/1 (1-11) Measured and simulated response of runoff during snowmelt has suggested that preferential water flow occurs as part of the infiltration process in glacial till. However, only a few quantitative studies have been presented. TDR measurements of soil water content were performed during the growing period in a till slope (7-10%) outside Stockholm. Soil cores were used to determine the water retention curve and the saturated hydraulic conductivity. A physically based one-dimensional model was used to simulate soil water dynamics in the slope. Two simulation approaches were used: a strict one-domain Darcian approach and a two-domain approach accounting for a bypass of the matrix flow system. The measured response of soil water content occurred within the first few hours after rainfall. This was best represented by the two-domain approach, while the response for the one-domain approach was significantly delayed with time and depth. The general behaviour of the soil water content throughout the season was, however, best simulated with a one-domain approach. The results indicated that preferential flow patterns through the unsaturated zone does not need to be considered to describe the seasonal pattern in glacial till soil. However, the results also point out that the purpose of the simulation is decisive when choosing a simulation approach, depending on whether the general soil water content over the season or the instant behaviour immediately after rainfall is of major interest. © IWA Publishing 2005. 1712 Development and field validation of the pestfate model in southern Ontario Bera P., Prasher S.O., Madani A. et al. Transactions of the American Society of Agricultural Engineers 2005 48/1 (85-100) A new pesticide movement model called PESTFATE (PESTicide Fate and Transport in Environment) has been developed by combining DRAINMOD, a well-known water table management model, and the pesticide submodel of PESTFADE. The pesticide sorption in the new model is based on two different techniques, namely, conventional mechanism and a new two-stage sorption method called Gamble kinetics. The model was validated by comparing the simulated midspan water table depths and atrazine [2-chloro-4-ethylamino-6-isopapylamino-1, 3, 5-triazine] concentrations against an independently collected dataset from a research site in southern Ontario. The experimental field consisted of 16 plots with two different water table management and four different tillage practices, replicated twice. Only the plots with conventional tillage and controlled drainage were used in this study. The model performed well in predicting the daily water table depths. Although the intercept and slope of the regression between the observed and predicted water table depths were significantly different from 0 and 1, respectively, the model efficiencies for 1992, 1993, and 1994 were 28%, 81%, and 64%, respectively, which shows a better accuracy for the last two years of the study. The normalized standard errors were within 15% to 20%, which indicates good model performance for water flow simulation. However, the correlation between the observed and simulated pesticide concentrations with both the conventional and Gamble kinetics was poor. Moreover, the Gamble kinetics did not significantly improve pesticide simulations (P < 0.05) as compared to the conventional method. The experiments were conducted on Brookston clay loam soil, which is known for developing soil cracks and consequently preferential flow. This could be one of the reasons for poorer model performance, especially with the Gamble kinetics. This was not the case in previous studies, which reported better simulation results with the new sorption mechanism, so the model requires additional field testing before any concrete conclusions can be drawn about its performance. There is also a need to test the model with other pesticides. © 2005 American Society of Agricultural Engineers. 1713 Hydraulic conductivity of a silt loam soil as affected by sample length Fuentes J.- P. and Flury M. Transactions of the American Society of Agricultural Engineers 2005 48/1 (191-196) Soil hydraulic conductivity is often measured with small laboratory samples. Due to sampling artifacts or spatial variability, small-scale laboratory samples may not yield representative conductivity measurements. The objective of this study was to analyze the effect of sample length on the saturated and nearsaturated hydraulic conductivity (K). An undisturbed soil core of 9 cm diameter and 25 cm length was extracted from the A horizon of a no-till, silt loam soil, and K was determined at hydraulic heads (matric potential heads) of 0, -4, -8, -12, -16, and -22 cm-H2 O under steady-state flow conditions. The core was then dissected incrementally from the bottom in 5 cm segments. At each dissection step, the remaining core and the cutoff core were re-saturated, and K was determined. Measured K varied considerably with core length, with the saturated conductivity being much more variable than the unsaturated conductivities. The use of consecutive 5 cm core segments to determine the effective K resulted in an underestimation of the conductivity compared to direct measurements on longer cores, possibly caused by smearing or compaction of cut surfaces during core dissection. Effective K determined from 5 cm core segments matched well with directly measured K only at hydraulic heads more negative than -16 cm-H2 O. The results of this study highlight that small cores on the order of a few cm may not be representative of a larger soil profile such as the plow layer or crop root zone. © 2005 American Society of Agricultural Engineers. 1714 Economic analysis of subsurface drip irrigation lateral spacing and installation depth for cotton Enciso J.M., Colaizzi P.D. and Multer W.L. Transactions of the American Society of Agricultural Engineers 2005 48/1 (197-204) Cotton lint yield, seed mass, fiber quality parameters, gross return, and net return were compared for subsurface drip irrigation (SDI) lateral spacing and installation depth in a clay loam soil in western Texas for three seasons. Drip laterals were spaced either in alternate furrows (2 m) or beneath every planted bed (1 m), and installation depths were either 0.2 or 0.3 m beneath the soil surface. Net return was gross return minus fixed and variable SOILS costs. Fixed costs included the annual payment for financing the initial investment of SDI materials and installation (5.00% interest over 10 years), the annual land lease, and the annual depreciation of the SDI system. Variable costs were those associated with cotton production and were similar for the two drip lateral spacings. Lint yield, seed mass, and gross and net returns were significantly greater for the 1 m lateral spacing in the first two seasons, but these parameters were significantly greater for the 2 m lateral spacing in the third season. These parameters were consistently greater (either numerically or significantly) for the 0.3 m lateral depth in all seasons. Most fiber quality parameters were not significantly different, and no consistent trends were observed. Lint yields ranged from 640 to 1,635 kg ha-1 , and net returns ranged from -$395 to $1,005 ha-1 . The low lint yield and resulting net loss were due to a germination failure in the second season for the alternate furrow spaced laterals. Additional seasons of study are required before conclusions might be drawn concerning the most economic lateral spacing for cotton production in the Trans-Pecos region of Texas, but the 0.3 m lateral depth resulted in greater net returns than the 0.2 m lateral depth. 1715 A precise irrigation system with an array of nozzles for plug transplant production Ohyama K., Murase H., Yokoi S. et al. Transactions of the American Society of Agricultural Engineers 2005 48/1 (211-215) A precise irrigation system with a 6 x 12 array of needle-like nozzles was developed for plug transplant production using 72cell plug trays. When a command for irrigation is given to the system, all of the nozzles are directly inserted into the corresponding cells at the same time to discharge a predetermined amount of water or nutrient solution. The amount of irrigated water from each nozzle (Q) can be controlled by adjusting the discharge time to keep the solenoid valve open (T) and by discharge pressure (P). The objectives of the present study were: (1) to obtain quantitative data for the control of Q, and (2) to examine the performance of the system during a plug transplant production period of 20 days. By adjusting T of each nozzle individually and P, a uniform distribution of Q was achieved over the tray. Consequently, a high value of Christiansen coefficient of uniformity was obtained (97.2% to 98.4%). During the plug transplant production period, the volumetric water content in each cell could be controlled by using the system without any growth deterioration of the transplants owing to the root damage caused by the nozzle insertion into the substrate. These results demonstrate that this system is feasible for precise irrigation management of plug transplant production. © 2005 American Society of Agricultural Engineers. 1716 Mechanisms of surface runoff genesis on a subsurface drained soil affected by surface crusting: A field investigation Augeard B., Kao C., Chaumont C. and Vauclin M. Physics and Chemistry of the Earth 2005 30/8-10 (598-610) Artificial drainage has been subject to widespread criticism because of its impact on water quality and because there is suspicion that it may have detrimental effects on flood genesis. The present work aims at a better understanding of the mechanisms controlling infiltration and surface runoff genesis, particularly in soils with artificial drainage and affected by surface crusting. A field experiment was conducted during one drainage season (November 2003-March 2004) in the Brie region (80 km east of Paris, France) on a subsurface drained silty soil. Water table elevation and surface runoff were monitored above the drain and at midpoint between drains. Soil water pressure head was measured at various depths and locations between the midpoint and the drain. Soil surface characteristics (microtopography and degree of structural and sedimentary crust development) were recorded regularly on the experimental site and on other plots of various drainage intensities. The results show that the first surface runoff events were induced by high water table. However, runoff was higher at midpoint between the drains because water table reached the soil surface at that point, thus considerably reducing infiltration capacity compared to that above the drain. Comparing different plots, the area with older drainage installation (1948) yielded the most surface runoff. Wider drain spacing, smaller drain depth and possible plugging may have led to a greater area of saturated soil between drains. During the 327 winter period, the impact of raindrops induced the formation of a structural crust on the soil surface. Furthermore, the development of the sedimentary crust, which was favored by water actually flowing on the soil surface during the high water table periods could be correlated with surface runoff volume. The formation of this crust had a significant impact on runoff occurrence at the end of the winter. Therefore, poorly drained fields presented more favorable conditions for both Horton type runoff and saturation excess runoff. Drainage effectively reduces surface runoff occurrences not only by lowering the water table in winter but also by limiting soil surface sealing. © 2005 Elsevier Ltd. All rights reserved. 1717 Can forest transformation help reducing floods in forested watersheds? Certain aspects on soil hydraulics and organic matter properties Wahl N.A., W¨ollecke B., Bens O. and H¨uttl R.F. Physics and Chemistry of the Earth 2005 30/8-10 (611-621) Former floodplains in many European countries increasingly suffer from serious floods due to intensified human activity. These floods have caused safety and ecological problems as well as they have resulted in economic losses in agricultural used watersheds. In this context, the influence of the management practice of forest transformation in forested areas on soil hydraulic properties is presented and discussed as a means of preventing such disasters at a reasonable cost and during a foreseeable period. Investigations were carried out in northeastern Germany on forest stands differing in tree populations and stand structure. It was found that infiltration capacity and hydraulic conductivity K exhibit overall low values nevertheless the tree species. This finding appears to be related to water repellency, the predominating texture, and a poor macroporosity. During the different stages of forest transformation, the type and amount of soil organic matter and humus in the litter layer change, leading to a decrease of the water capacity of the litter layer and the uppermost part of the mineral soil. Furthermore, these changes affect soil properties connected with water repellency. It is concluded that for the approximate duration of one century the practice of forest transformation does not contribute to flood prevention through enhanced infiltration capacity or water retention. © 2005 Elsevier Ltd. All rights reserved. 1718 Temporal dynamics of soil water in oak forest stand of Southern Slovakia Tuˇzinsk´y L. Ekologia Bratislava 2005 24/3 (304-313) Time and spatial variability of the soil water depends on the weather characteristic course, on soil hydrophysical characteristics and on forest stand transformation influence. Analysis of soil water available for plants during the growing season shows that the water dynamics in the soil under the oak forest stand is most intense in the upper (0-50 cm) layers of the soil profile. Water uptake and loss from this soil layer results in transition of the soil water from one category to another, especially due to the osmotic preassure of the soil and the water active transport via fine roots. At the beginning of the growing season capillary movable water category prevails in the soil profile with easy available water supply. Radiation and air temperature increase leads to the gradual decrease of soil water content. Increase of evapotranspiration (> 5 mm.day-1 ) is folowed by the process of water supply decrease. During the culminating drying off period (July, August) the soil water supply decreases to the category of capillary immovable water. During extremely dry season the water supply in the soil can decrease to the wilting point level. Soil water becomes capillary bound and non-available for plants. Loss of contact between the fine roots and water results in decrease of transpiration and assimilation. Premature fall off of physiologically weakened leaves is recorded. Under such conditions the oak resistance towards damaging factors is decreased. 1719 Flux-saturation relationship for unsaturated horizontal flow Evangelides C., Tzimopoulos C. and Arampatzis G. Soil Science 2005 170/9 (671-679) The prediction of unsaturated flow is a never-ending quest for many scientists. Many methods exist with their corresponding 328 SOILS advantages and disadvantages, such as semianalytic, finite difference, finite element, finite control volume, and flux-saturation. The last one, even though it belongs to the semianalytic group, is very interesting due to its simplicity and the way it approaches the physical problem. During laboratory research, a new intuitive monoparametric fitting function was used for F(). The purpose of this research was to examine the range of variation of the new fitting function coefficient and the feasibility to replace it with a constant. A series of experiments was carried out on horizontal absorption under constant-head conditions, using three different soil types, to measure their F() function. F() values were also obtained for four other soils, using different methods. The soils that were examined were characterized from silt to sand, according to the textural triangle of the United States Department of Agriculture. Actual F() functions were then calculated in each soil. The proposed F() function was compared with the limiting F() function for linear and Dirac soil and with preexisting ones. The results were satisfactory both in shape and in quantity, leading to a new expression for F() for all soil types. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1720 Modeling water flow behavior where highly treated effluent is applied to soil at varying rates and dosing frequencies Hassan G., Reneau Jr. R.B., Hagedorn C. and Saluta M. Soil Science 2005 170/9 (692-706) There is a need for alternative on-site wastewater systems (OWS) that can be used in soils and on sites not suitable for conventional OWS (septic tank and gravity dispersal) while minimizing ground and surface water degradation. One method to accomplish this is to apply highly treated effluent (HTE), using a technology such as a subsurface drip irrigation system (SDIS), where effluent is dispersed uniformly to soil and the dosing frequency can be controlled. Since there are a large number of factors that can affect OWS function, the ability to evaluate these factors by using a simulation model would greatly improve our ability to design OWS that solve problems while having minimal environmental impact. This study was conducted to determine the potential to simulate HTE [recirculating media filter effluent (RMFE)] flow, soil water content and potential, and changes in soil water mass balance using HYDRUS-2D (a numerical model), in which RMFE was applied at varying rates (518, 1036, and 2071 cm 3 d-1 ) and dosing frequencies (6, 12, and 24 doses per day) to soil columns designed to simulate a SDIS. Fecal coliform numbers were used to measure the effectiveness of these treatments. We hypothesized that fecal coliform numbers would decrease when effluent was applied in smaller (more frequent) doses. Results showed that HYDRUS-2D could be successfully used to predict RMFE flow, soil water potential and moisture content, and soil mass balance. Although dosing RMFE more frequently had no effect on fecal coliform numbers at the two lowest application rates (518 and 1036 cm3 d -1 ), there was a significant decrease in fecal coliforms as dosing frequency increased at the highest rate of application (2071 cm3 d-1 ). Copyright © 2005 by Lippincott Williams & Wilkins. 1721 Soil hydraulic properties in a marly gully catchment (Draix, France) Esteves M., Descroix L., Mathys N. and Lapetite J.M. Catena 2005 63/2-3 (282-298) Runoff is one of the main factors controlling gully development. Concentrated flow erosion occurs where flow discharge and velocity exceed critical values. In Southern French Alps, in black marl gully catchments, runoff from hillslopes occurs in the form of Hortonian overland flow because rainfall intensities exceed the infiltration capacity of the soil. In such a situation, spatial variability of infiltration capacities is critical for describing the runoff production. This study reports detailed field measurements of near-saturation and saturated infiltration properties: capillary sorptivity (S) and hydraulic conductivity (K). A total of 140 infiltration tests were conducted using tension disc and ponded ring infiltrometers on 6 different regoliths (weathering profile) encountered in a marly gully catchment. The main objectives were to improve our knowledge of the spatial variability of infiltration in black marl areas and to compare different field and data analysis methods. Hydraulic conductivity values K(h) at supply pressure heads (h) ranging from h = - 100 up to h = 0 mm were calculated using steady state flow and Wooding’s equation [Wooding, R.A., 1968. Steady infiltration from shallow circular pond. Water Resour. Res. 4 (6), 1259-1273]. K(h = 0 mm) was also estimated from the ponded ring infiltrometer data set. The estimation of sorptivity was based on transient flow and the solution of Haverkamp et al. [Haverkamp, R., Roos, P.J., Smettem, K.R.J., Parlange, J.Y., 1994. Three dimensional analysis of infiltration from the disc infiltrometer. 2. Physical based infiltration equation. Water Resour. Res. 30 (11), 2931-2935]. Three methods were used to analyse tension disc infiltrometer data: multiple radii, multiple potential and single test. Only the multiple radii method was found not suitable in our context due to a large spatial variability in the infiltration properties over small distances. The other methods gave similar estimates of the hydraulic conductivity. The hydraulic conductivity K(h) ranged up to two orders of magnitude. This result confirms the role played by structural voids when the regolith is at near saturation. The dispersion of the estimates of field saturated hydraulic conductivity is larger than unsaturated values. The spatial differences found are explained by the topographical position and by the regolith structure observed for the 6 sites. An analysis based on the ponding time show that the regolith type plays an important role in the dynamic of the runoff production. © 2005 Elsevier B.V. All rights reserved. 1722 Ecological characteristics of soil water and its relations to landform and vegetation in a small semiarid watershed in a loess hilly area of China Liu W.Z., Hu M.J., Li F.M. and Zhang X.C. International Journal of Sustainable Development and World Ecology 2005 12/3 (326-333) There is an urgent need to study soil water resources and ecohydrological characteristics in depth so as to carry forward ecological environmental construction in the Loess Plateau. Soil moisture was measured to a depth of 5 m on 11 sites with different landforms and land uses in a transect of the Zhonglianchuan watershed during 2002. The watershed is located in the northern Yuzhong County, Gansu Province, and is part of a semiarid and loess hilly area. There were different types of soil moisture variations in 2002 on the 11 sites. Soil moisture contents were low on all sites, and the average water contents at 2 to 5-m depth were usually lower than 10% by weight, and the lowest water contents were found in slope land under Medicago sativa and Caragana korshinskii vegetation. The dry soil layer is common in this area, not only under planted vegetation but also under natural vegetation. The soil moisture in a slope segment or area can be increased by collecting and harvesting surface runoff from upslope areas. One effective way to collect runoff is by constructing level terraces, alternating with sloping lands. The proportion of various grasslands, acreage of alfalfa, and sustainable development of the region should be further studied in order to successfully convert cultivated land into grassland. 1723 Water films and scaling of soil characteristic curves at low water contents Tuller M. and Or D. Water Resources Research 2005 41/9 (1-6) [1] Individual contributions of capillarity and adsorptive surface forces to the matric potential are seldom differentiated in determination of soil water characteristic (SWC) curves. Typically, capillary forces dominate at the wet end, whereas adsorptive surface forces dominate at the dry end of a SWC where water is held as thin liquid films. The amount of adsorbed soil water is intimately linked to soil specific surface area (SA) and plays an important role in various biological and transport processes in arid environments. Dominated by van der Waals adsorptive forces, surface-water interactions give rise to a nearly universal scaling relationship for SWC curves at low water contents. We demonstrate that scaling measured water content at the dry end by soil specific surface area yields remarkable similarity across a range of soil textures and is in good agreement with theoretical predictions based on van der Waals interactions. These scaling relationships are important for accurate description of SWC curves in dry soils and may provide rapid and reliable estimates of soil specific surface area from SWC measurements for matric potentials below -10 MPa conveniently measured with the chilled-mirror dew point technique. Surface area estimates acquired by fitting the scaling relationship to measured SWC data were in good agreement with SA data measured by standard SOILS methods. Preliminary results suggest that the proposed method could provide reliable SA estimates for natural soils with hydratable surface areas smaller than 200 m2 /g. Copyright 2005 by the American Geophysical Union. 1724 Non-linear radiation for bidimensional Richards equation in subsurface agricultural drainage (Spanish) (Radiaci´on no lineal en la ecuaci´on de Richards bidimensional aplicada al drenaje agrcola subterr´aneo) Zavala M., Fuentes C. and Saucedo H. Ingenieria Hidraulica en Mexico 2005 20/4 (111-119) A mechanistic approach is presented to simulate the hydraulic operation of a subsurface agricultural drainage system that consists in numerically coupling the bidimensional Richards equation for the water flow in the soil with the continuity equation and a resistance law for the water flow in the drain. This coupling is made by imposing a non-linear radiation condition on the drain perimeter (Zavala et al., 2003). By using experimental data, the description capacity of both the non-linear radiation condition and the classical approximation reported in the literature as seepage-face condition is evaluated. By comparison with experimental information, it is shown that the seepage-face condition overestimates drainage flow and the recession of the water table, due to the fact that it assumes a null resistance in the saturated soil-drain interface. The experimental validation allows to conclude that the description of mass and energy transferences in an agricultural subsurface drainage system during the recession of the water table must be made by imposing the non-linear radiation condition in the circumference of the drain. 1725 Spatial heterogeneity of soil moisture after raining at forest-grassland landscape boundary in hilly area of Loess Plateau (Chinese) You W., Zeng D., Liu M. et al. Chinese Journal of Applied Ecology 2005 16/9 (1591-1596) Soil moisture is a main factor limiting vegetation restoration in semi-arid region. In this paper, the spatial variability of different layers soil moisture after raining at the forest-grassland boundary in hilly area of Loess Plateau were studied by traditional and geostatistical analysis methods. The results showed that the moisture content in surface (0-10 cm) and subsurface soil layer (10-20 cm) of grassland was higher than that of forestland. The two layers soil moisture content at forest-grassland boundary showed a small variation but an obvious ecological distribution. By using moving split-window techniques, it was obtained that the width of edge influence in surface and subsurface layer was 8 and 6 m, respectively. Geostatistical analyses showed that the spatial distribution of two layers soil moisture had a pure nugget effect in grassland, linear model in forestland, and spherical model in forest-grassland boundary. The spatial heterogeneity of two layers soil moisture was higher at forest-grassland boundary than at forestland and grassland, which had a stronger spatial dependence and autorelation. Kriging maps expressed the spatial structural characters. The distribution of soil moisture in two layers showed a strip shape near forest edge, and a patch shape far from the edge. 1726 Simulation of energy and water balance in Soil-Vegetation-Atmosphere Transfer system in the mountain area of Heihe River Basin at Hexi Corridor of northwest China Kang E., Cheng G., Song K. et al. Science in China, Series D: Earth Sciences 2005 48/4 (538-548) In the mountain area of inland Heihe River Basin at Hexi Corridor of northwest China during the vegetation growing season from May to September, the Simultaneous Heat and Water (SHAW) model of Soil-Vegetation-Atmosphere Transfer (SVAT) system is applied to simulating and studying energy and water balance of the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope and the grassland at the sun-facing slope. The simulation of energy balance indicates that net radiation of the grassland at the sunfacing slope is more than that of the Picea crassifolia forest and the grassland by the forest at the shaded slope. The energy outgoing components are the first latent heat and next sensible heat from the grassland both at the shaded slope and the sun-facing slope, but those at the former are less. The energy outgoing components are the first sensible heat and next latent heat from 329 the Picea crassifolia forest. The composition and distribution of energy in the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope make the soil layer receive less energy, which therefore, especially the forest possesses the energy conditions for soil water conservation. The simulation of water balance indicates that the water loss of the grassland at the sun-facing slope is mainly caused by soil evaporation, while evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is less than that of the grassland at the sun-facing slope. Half of the evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is consumed by transpiration. After precipitation, the soil water storage is increased much more for the Picea crassifolia forest and also more for the grassland by the forest at the shaded slope. Therefore the shaded slope vegetation, especially the forest is favorable for soil water storage. Copyright by Science in China Press 2005. Chemistry 1727 Agronomic and environmental impacts of a single application of heat-dried sludge on an Alfisol Gavalda D., Scheiner J.D., Revel J.C. et al. Science of the Total Environment 2005 343/1-3 (97-109) A field experiment was conducted on Alfisols in South-West France to assess the agronomic and environmental impacts of a single application of heat-dried sludge pellets at 11.1 Mg dry matter ha-1 . The sludge pellets, with a moisture level of 9.5%, were spread on an irrigated crop of maize (Zea mays L.). This treatment was compared with inorganic fertilization (urea and diammonium phosphate mixed with KCl). Soil properties, yield and the composition of maize and the quality of drained water were monitored over 1 year to detect any changes resulting from sludge application. Amongst several determined soil properties, only two were significantly modified by the sludge application: The nitric nitrogen stock of the soil was higher in the inorganic fertilized plot, whereas Olsen-P soil content was higher in the sludge-amended plot. Agronomic recovery rates of N and P added by sludge were high: For the first crop following application, total amounts of N and P supplied by the sludge had the same efficiency as approximately 45% of the N and P amounts supplied by inorganic fertilizer. This ratio was 7% for the N uptake by the second maize crop. The quality and quantity of maize were equally good with both types of fertilization. During the 2 years following sludge spreading, N leaching remained as low in the sludged plot as in the inorganically fertilized one. The Cu, Zn, Cr, Cd, Pb and Ni composition of the drainage water was affected by neither of the types of amendment. From the heavymetal contents of the soil, water and maize monitored over 1 year in the field experiment and from literature data for cow manure and atmospheric emissions, a theoretical balance between crop soil heavy-metal input and output over one century was drawn up. The long-term impact of cow manure on Zn, Ni and Cr in soil is higher than that of the studied heat-dried sludge. Obviously, sludge tended to cause a strong increase in soil Cu storage, valued for these soils, which are otherwise very Cu deficient. © 2004 Elsevier B.V. All rights reserved. 1728 N fertilisation, soil type and cultivars effects on N use efficiency in tef [Eragrostis tef (Zucc.) Trotte] Tulema B., Zapata F., Aune J. and Sitaula B. Nutrient Cycling in Agroecosystems 2005 71/2 (203-211) Tef [Eragrostis tef (Zucc.) Trotte] is a major staple crop in Ethiopia and a large proportion of the imported fertiliser is being applied to tef fields. However, since the 1980s the yield on farmers’ fields has stagnated. Response of the crop to applied fertiliser is influenced by several factors. We aimed to study the fertiliser N use efficiency (FNUE) of four tef varieties from ammonium sulphate and urea on different soil types with the help of the 15 N isotopic dilution technique. Three experiments were conducted under greenhouse and field conditions. On a typic Eutrocrept soil, higher percent N derived from fertiliser (% Ndff) and % FNUE were obtained for all the tested tef varieties when the N source was urea, while percent N derived from 330 SOILS soil (% Ndfs) was higher for ammonium sulphate. The mean % FNUE for urea and ammonium sulphate was 49 and 34%, respectively. When the varieties were grown on a Nitosol or a Vertisol and ammonium sulphate was applied, the % Ndff, the total and fertiliser N yield and % FNUE of the tef varieties were higher on a eutric Nitosol compared to the Vertisol. The mean % FNUE was 61.3 for the Nitosol and 27.8 for the Vertisol. In an ‘on farm’ experiment, relatively higher FNUE (33.3%) was obtained on an Andosol compared to Vertisols (17 and 27%). The tested varieties showed no difference in FNUE. As tef is the most important crop grown on Vertisols in Ethiopia, the low FNUE has a direct negative implication for the livelihood of the farmers and the environment. © Springer 2005. 1729 Does pyrite oxidation contribute to the acidification of tropical peat? A case study in a peat swamp forestin Central Kalimantan, Indonesia Haraguchi A., Akioka M. and Shimada S. Nutrient Cycling in Agroecosystems 2005 71/1 (101-108) The chemical properties of peat pore water in the basin of the Sebangau River and Lahei district, Central Kalimantan, Indonesia, were studied. We analyzed major ions, pH, electrical conductivity (EC) and redox potential (Eh) of the peat pore water with reference to their vertical profile. We evaluated the contribution of sulfates to the acidi.cation of peat by including data from Furen mire, eastern Hokkaido, Japan. The coastal peat of Furen mire and the peat in Paduran in the lower basin of the Sebangau River included extraordinarily high concentrations of sulfates (> 1000 mg/l) compared to the peat in the middle and upper basins of the river (< 10 mg/l). High concentrations of sulfates, however, did not lead to a low pH for the peat. The present findings suggest that the acidification of the peat pore water is subject to the production of organic acids originating from peat decomposition, rather than the production of sulfuric acid produced by pyrite oxidation in the underlying mineral sediments. © Springer 2005. 1730 Simulating processes of soil phosphorus in geologically young acidic soils of Finland Yli- Halla M., Tattari S., B¨arlund I. et al. Transactions of the American Society of Agricultural Engineers 2005 48/1 (101-108) To properly simulate phosphorus (P) loading from agricultural land to waters, changes in soil P status and processes affecting soil P have to be described adequately. For practical reasons, a model has to rely on data that are commonly available. In this study, the P submodel of the ICECREAM model, based on the CREAMS, GLEAMS, and EPIC models, was adapted to simulate young acidic soils, which prevail in Finland. These soils have a high P sorption capacity, plenty of inorganic P in a non-reactive apatitic form, and the organic matter content (Or ) in the plow layer is commonly about 5%. The model was modified mainly on the basis of 12 long-term fertilization experiments and tested on three other soils. The P pools considered were labile P (P il ), active inorganic P (Pia ), stable inorganic P (P is ), fresh organic P (Pof ), and more stable organic P (Poh ). The major model modifications made were: (1) initialization of Pil from the Finnish soil test results (ammonium acetate extractable P, PAAC ); (2) initialization of Pia and Pis from Pil , assuming equilibrium; (3) revision of the P availability factor (Fl ), which regulates the flow between Pil and Pia ; and (4) calculation of the initial values of Poh from soil organic carbon content. These modifications aimed to improve simulation of Pil on the basis of data obtained from soil testing. Proper simulation of changes in Pil , reflected by the soil test P (P AAC ), is critical since it regulates the level of dissolved P in runoff water. After the modifications, the model was able to predict changes in PAAC at annual P application rates of 0 and 30 kg ha-1 in cereal cropping, but could not fully cope with a large surplus of P resulting from an annual rate of 60 kg P ha-1 . © 2005 American Society of Agricultural Engineers. 1731 Carbaryl, 2,4-D, and Triclopyr adsorption in thatchsoil ecosystems Raturi S., Islam K.R., Caroll M.J. and Hill R.L. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/5 (697-710) Thatch development in intensively managed turf sites may cause environmental concerns for greater sorption or leaching of applied chemicals in terrestrial ecosystems. To determine the ad- sorption potential of Carbaryl (1-Napthyl N-methylcarbamate), 2,4-D (2,4-dichloro-phenoxyacetic acid), and Triclopyr (3,5,6trichloro-2-pyridinyloxyacetic acid) in turf ecosystems, composite thatch and underlying soil samples from three- and sixyear-old stands of cool-season Southshore creeping bentgrass (Agrostis palustris Huds.) and warm-season Meyer zoysiagrass (Zoysiajaponica Steud.) were collected. The samples were processed and analyzed for total organic carbon (COrg ); extractable (CExt ), humic (CHA ) and fulvic acid (C FA ); anthrone reactive nonhumic carbon (ARC) fractions; and C HA and CFA associated iron (Fe) contents. Pesticide adsorption capacity (Kf ) and intensity (1/n), organic carbon partition coefficient (KOC ) and Gibbs free energy change ( G) were calculated for thatch materials and the underlying soils using a modified batch/flow technique. Both bentgrass (BT) and zoysiagrass thatch (ZT) contained a greater concentration of CExt CFA , CHA , and ARC than the respective soils (BS and ZS). The CExt , CFA , CHA , and ARC concentration was higher in BT compared with ZT. The BT contained a greater concentration of bound Fe in both CFA and C HA fractions than in BS, whereas ZT had more bound Fe in C HA fraction than in ZS. On average, the BT had a greater concentration of bound Fe in CExt , CFA , and CHA fractions than in the ZT. Among the pesticides, Carbaryl had higher K f and 1/n values than 2,4-D and Triclopyr for both thatch and soil. Although the KOC and G values of Carbaryl were higher in both BT and ZT than in the underlying soils, the KOC and G values of 2,4-D were significantly higher in BS and ZS than in the overlying thatch materials. The 2,4-D and Triclopyr had higher leaching indices (LI) than Carbaryl for both BT and ZT materials than the respective soils. The Carbaryl, however, had a higher LI for soils than for thatch materials. Averaged across thatch materials and soils, COrg accounted for 96, 85, and 84% variations in Carbaryl, 2,4-D, and Triclopyr adsorption, respectively. Among the COrg fractions, lignin followed by CFA and CHA accounted for greater adsorption of pesticides, especially Carbaryl. The concentration of CHA and CFA bound Fe did not correlate with Kf and 1/n values of pesticides. Copyright © Taylor & Francis Inc. 1732 Sorption of three tetracyclines by several soils: Assessing the role of pH and cation exchange Sassman S.A. and Lee L.S. Environmental Science and Technology 2005 39/19 (7452-7459) Tetracyclines (TCs) are widely used in veterinary medicine for treatment and prevention of disease and are present in animal waste products. Detection of TCs in soil, sediments, and water, and the growing concern of their potentially adverse effect on natural ecosystems have resulted in a need to understand their behavior in aqueous soil systems. TCs have multiple ionizable functional groups such that at environmentally relevant pH values, they may exist as a cation (+00), zwitterion (+-0), or a net negatively charged ion (+--), which complicates predicting their sorption, availability, and transport. We investigated the sorption of oxytetracycline (DTC), tetracycline (TC), and chlortetracycline (CTC) by several soils varying in pH, clay amount and type, cation exchange capacity (CEC), anion exchange capacity (AEC), and soil organic carbon in 0.01 N CaCl2 , 0.001 N CaCl2 , and 0.01 N KCl. All three TCs are highly sorbed, especially in acidic and high clay soils. When normalized to CEC, sorption tends to decrease with increasing pH. A sorption model in which species-specific sorption coefficients normalized to pH+-0 +-dependent CEC (K+00 d , Kd , and K d ) and weighted by the pHdependent fraction of each species fit the data well across all soils except for a soil rich in gibbsite and high in AEC. Resulting K+00 d values were more than an order of magnitude larger than values +-0 +-+00 for either Kd and Kd values such that Kd alone described most of the sorption observed as a function of pH for eight soils that varied in their mineralogy and pH (pH ranged from 4 to 8). © 2005 American Chemical Society. 1733 Transformation of carbon tetrachloride by thiol reductants in the presence of quinone compounds Doong R.- A. and Chiang H.- C. Environmental Science and Technology 2005 39/19 (7460-7468) Quinones are present in trace amounts in natural organic matter. The addition of thiol compounds to quinones produces reactive electron-transfer species that may be important for the trans- SOILS formation of chlorinated hydrocarbons under sulfate-reducing conditions. This study systematically investigated the transformation of carbon tetrachloride (CCl4 ) in homogeneous aqueous solutions containing quinones as electron-transfer mediators and thiol compounds as bulk reductants. The thiol compounds, including sodium hydrosulfide (NaHS) and cysteine, were found to effectively transform CCl4 . The transformation of CCl4 followed pseudofirst-order kinetics, and the pseudo-first-order rate constants (kobs ) were (3.24 0.46) 10-7 and 1.04 10-7 s-1 , respectively, when solutions contained NaHS and cysteine alone. Addition of quinone compounds, including anthraquinone-2,6disulfonate (AQDS), benzoquinone (BQ), juglone (JQ), naphthoquinone (NQ), lawsone (LQ), and menadione (MQ), increased the transformation rate and efficiency of CCl4 . The k 0bs values for CCl4 transformation in the presence of quinones were 2.671 times higher than those for the thiol compounds alone. The enhancement efficiency followed the order JQ > NQ > BQ AQDS > LQ > MQ. Spectroscopic studies indicated that the quinone compounds generated various active electron-transfer mediators to transfer electrons from the bulk reductants to CCl4 . BQ and NQ produced mercaptoquinones as active redox mediators that significantly enhanced the transformation rate of CCl 4 in the presence of NaHS. The addition of thiol reductants produced large amounts of AQDS semiquinone radical as the electron shuttle. In addition, MQ and LQ were reduced by NaHS to give hydroquinone, which slightly enhanced the transformation efficiency of CCI4. These results clearly indicate that the enhanced efficiency of quinones for the transformation of chlorinated hydrocarbons is specifically related to the produced reactive species. Mercaptoquinone is a more active mediator than either semiquinone or hydroquinone for transferring electrons in a reducing environment containing thiol reductants. © 2005 American Chemical Society. 1734 Fate and transport of monoterpenes through soils. Part I. Prediction of temperature dependent soil fate model input-parameters Van Roon A., Parsons J.R., Te Kloeze A.- M. and Govers H.A.J. Chemosphere 2005 61/5 (599-609) Monoterpenes are C10HnOn compounds of natural origin and are potentially environmentally safe substitutes for traditional pesticides. Still, an assessment of their environmental behaviour is required. As a first step in a theoretical study focussing on monoterpenes applied as pesticides to terrestrial environments, soil fate model input-parameters were determined for 20 monoterpenes with widely different structural characteristics. Inputparameters are the water solubility (SW ), vapour pressure (P), n-octanol-water partition coefficient (KOW ), atmospheric air and bulk water diffusion coefficients (DAair and DWwater), first order biodegradation rate constants (k), and their temperature dependence. Values for these parameters were estimated or taken from previous experimental work. The quality of the estimations was discussed by focussing on their statistics and by comparison with available experimental data. From these properties, the air-water partition coefficient (KAW , Henry’s Law constant), the interface-water partition coefficient (KIW ) and the organic matter-water partition coefficient (KOM ) could be estimated with varying levels of accuracy. In general, little experimental data turned out to be available on biodegradation rate constants and on the temperature dependence of physico-chemical parameters. © 2005 Elsevier Ltd. All rights reserved. 1735 Effect of dissolved organic matter on copper-zinc competitive adsorption by a sandy soil at different pH values Mesquita M.E. and Carranca C. Environmental Technology 2005 26/9 (1065-1072) The effect of dissolved organic carbon from sewage sludge on copper and zinc adsorption and interaction on samples from the surface layer (0 - 10 cm) of a sandy soil (Gleyic Podzol) were studied at two pH levels (4 and 7). This soil presented acidification hazards and sewage sludge with a high content of Cu and Zn was used as a fertilizer. Soil samples were treated by solutions of Cu and Zn as nitrate salts with concentration levels up to 30 mg l-1 in a Ca(NO3 )2 background at a constant level (180 mg l-1 ) of dissolved organic carbon (DOC). Copper and zinc sorption capacity decreased in the presence of DOC. As the pH increased, the decrease in Cu adsorption due to interaction 331 with DOC was more obvious. Conversely, without addition of DOC, Cu and Zn adsorption increased with pH. More Cu than Zn was adsorbed. Soil sorption of these cations was described by equilibrium isotherms that fitted both Langmuir and Freundlich type equations, presenting however a better fit to the Freundlich equation (R2 >98%). Adsorption dependence on DOC was more noticeable at pH 7. © Selper Ltd., 2005. 1736 Tylosin sorption to silty clay loam soils, swine manure, and sand Clay S.A., Liu Z., Thaler R. and Kennouche H. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/6 (841-850) The objectives of this study were to assess sorption and desorption of tylosin, a macrolide antimicrobial chemical used in swine, cattle, and poultry production, in three silty clay loam soils of South Dakota and compare soil sorption to sand and manure sorption. The silty clay loam soils, from a toposequence in eastern South Dakota, standardized sand samples, and swine manure were used in 24-h batch sorption studies with tylosin concentrations ranging from 25 to 232 mole/L. Desorption from soil was conducted over a four-day period. Partition coefficients, based on the Freundlich isotherm (Kf ) or Kd values, were calculated. Kf values for the silty clay loams were similar, not influenced by landscape position, and averaged 1350 with isotherm slopes ranging from 0.85 to 0.93. Kf values for sand were dependent on solution/sand ratios and pH, ranging from 1.4 to 25.1. Kd values of manure were dependent on the solution type and ranged from 840 L/kg with urine to about 175 L/kg when sorbed from water. Desorption of tylosin from each soil over the four-day period was <0.2% of the amount added. The soils’ high Kf values and low desorption amounts suggest that once tylosin is in these soils, leaching to lower depths may not occur. However, this does not preclude runoff with soil eroded particles. If tylosin reaches a sand aquifer, through bypass flow or other mechanism(s), movement in the aquifer most likely would occur. Copyright © Taylor & Francis Inc. 1737 Recent atmospheric Pb deposition at a rural site in southern Germany assessed using a peat core and snowpack, and comparison with other archives Le Roux G., Aubert D., Stille P. et al. Atmospheric Environment 2005 39/36 (6790-6801) In a peat bog from Black Forest, Southern Germany, the rate of atmospheric Pb accumulation was quantified using a peat core dated by 210 Pb and 14 C. The most recent Pb accumulation rate (2.5 mg m-2 y-1 ) is similar to that obtained from a snowpack on the bog surface, which was sampled during the winter 2002 (1 to 4 mg m-2 y -1 ). The Pb accumulation rates recorded by the peat during the last 25 yr are also in agreement with published values of direct atmospheric fluxes in Black Forest. These values are 50 to 200 times greater than the "natural" average background rate of atmospheric Pb accumulation (20 g m-2 y-1 ) obtained using peat samples from the same bog dating from 3300 to 1300 cal. yr B.C. The isotopic composition of Pb was measured in both the modern and ancient peat samples as well as in the snow samples, and clearly shows that recent inputs are dominated by anthropogenic Pb. The chronology and isotopic composition of atmospheric Pb accumulation recorded by the peat from the Black Forest is similar to the chronologies reported earlier using peat cores from various peat bogs as well as herbarium samples of Sphagnum and point to a common Pb source to the region for the past 150 years. In contrast, Pb contamination occurring before 1850 in southwestern Germany, differs from the record published for Switzerland mainly due to the mining activity in Black Forest. Taken together, the results show that peat cores from ombrotrophic bogs can yield accurate records of atmospheric Pb deposition, provided that the cores are carefully collected, handled, prepared, and analysed using appropriate methods. © 2005 Elsevier Ltd. All rights reserved. 1738 Facilitation of pentachlorophenol degradation in the rhizosphere of ryegrass (Lolium perenne L.) He Y., Xu J., Tang C. and Wu Y. Soil Biology and Biochemistry 2005 37/11 (2017-2024) The phytoremediation of xenobiotics depends upon plant-mi- 332 SOILS crobe interactions in the rhizosphere, but the extent and intensity of these effects are currently unknown. To investigate rhizosphere effects on the biodegradation of xenobiotics, a glasshouse experiment was conducted using a specially designed rhizobox where ryegrass seedlings were grown for 53 days in a soil spiked with pentachlorophenol (PCP) at concentrations of 8.7 0.5 and 18 0.5 mg kg-1 soil. The soil in the rhizobox was divided into six separate compartments at various distances from the root surface. Changes in PCP concentrations with increasing distance from the root compartment of the rhizobox were then assessed. The largest and most rapid loss of PCP in planted soil was at 3 mm from the root zone where total PCP decreased to 0.20 and 0.65 mg kg-1 , respectively with the two PCP treatments. The degradation gradient followed the order: near-rhizosphere>root compartment>far- rhizosphere soil zones for both concentrations where ryegrass was grown. In contrast, there was no difference in PCP concentration with distance in the unplanted soil. The increases in both soil microbial biomass carbon and the activities of soil urease and phosphatase were accompanied by the enhanced degradation of PCP, which was higher in the near-rhizosphere than far-rhizosphere soil. The results suggest that the effect of root proximity is important in the degradation of xenobiotics such as PCP in soil. © 2005 Elsevier Ltd. All rights reserved. 1741 Quantification and bioavailability of scyllo-inositol hexakisphosphate in pasture soils Turner B.L., Mahieu N., Condron L.M. and Chen C.R. Soil Biology and Biochemistry 2005 37/11 (2155-2158) The recent identification of scyllo-inositol hexakisphosphate in alkaline soil extracts by solution 31 P NMR spectroscopy allowed us to investigate this compound in soils by re-analyzing spectra from two previously published studies. Concentrations of scyllo-inositol hexakisphosphate in 29 temperate pasture soils from England and Wales ranged between 11 and 130 mg P kg-1 soil and accounted for between 4 and 15% of the soil organic phosphorus. The ratio of scyllo-inositol hexakisphosphate to myo-inositol hexakisphosphate ranged between 0.29 and 0.79. In a 10 month pot experiment with six grassland soils from New Zealand, growth of pine seedlings (Pinus radiata D. Don) decreased scyllo-inositol hexakisphosphate concentrations by between 10 and 46%. Growth of ryegrass (Lolium perenne L.) decreased scyllo-inositol hexakisphosphate in three low-nutrient soils by 5-21%, but increased it in three other soils by 1116%. We conclude that scyllo-inositol hexakisphosphate is an important component of soil organic phosphorus with potential ecological significance. © 2005 Elsevier Ltd. All rights reserved. 1739 Organic acid behaviour in a calcareous soil implications for rhizosphere nutrient cycling Str¨om L., Owen A.G., Godbold D.L. and Jones D.L. Soil Biology and Biochemistry 2005 37/11 (2046-2054) Calcareous soils are frequently characterized by the low bioavailability of plant nutrients. Consequently, many vascular plant species are unable to successfully colonize calcareous sites and the floristic composition of calcareous and acid silicate soils has been shown to differ markedly. The root exudation of oxalate and citrate has been suggested to play a pivotal role in same nutrient acquisition mechanisms operating in calcareous soils. The aim of this study was therefore to investigate the nutrient extraction efficiency of three individual organic acids commonly identified in root exudates, i.e. citric, malic and oxalic acid. Our results clearly demonstrate the context dependent nature of nutrient release by organic acids. The degree of P extraction was highly dependent on which organic acid was added, their concentration and pH, and their contact time with the soil. P is generally more efficiently extracted by organic acids at a high pH and follows the series oxalate>citrate>malate. The opposite relationship between pH and extraction efficiency was apparent for most other cations examined (e.g. Zn, Fe), which are more efficiently extracted by organic acids at low pH. A serious constraint to the ecological importance of organic acid exudation in response to P deficiency is, however, their very low P mobilization efficiency. For every mol of soil P mobilized, 1000 mol of organic acid has to be added. It can, however, be speculated that in a calcareous soil with extremely low P concentrations it is still beneficial to the plants to exude organic acids in spite of the seemingly high costs in terms of carbon. © 2005 Elsevier Ltd. All rights reserved. 1742 Mineralisation of C and N from root, stem and leaf residues in soil and role of their biochemical quality Abiven S., Recous S., Reyes V. and Oliver R. Biology and Fertility of Soils 2005 42/2 (119-128) The influence of biochemical characteristics of 15 crop residues on C and N mineralisation in soil was investigated by following the decomposition of roots, stems and leaves of four subtropical species and one temperate species buried into the soil. The C, N and polyphenols contents were measured in different biochemical pools obtained from residues of the different organs. The mineralisation of root C was significantly lower than that of leaves and stems. Chemical analysis showed a higher polyphenol content in the leaves and a higher ligninlike content in the roots. Carbon and N mineralisation were simulated with the STICS decomposition submodel and tested against the data set. The model predicted leaf and stem C mineralisation for all five species fairly accurately, but failed to predict root C mineralisation, indirectly revealing the more complex composition of the root tissue. The results showed the interest of separately considering the different plant parts when studying plant residue decomposition and the need to develop other methods of residue quality characterisation to improve the prediction of residue decomposition. 1740 Availability of CO2 as a factor affecting the rate of nitrification in soil Azam F., Gill S. and Farooq S. Soil Biology and Biochemistry 2005 37/11 (2141-2144) A laboratory incubation experiment was conducted to demonstrate that reduced availability of CO2 in soil may be an important factor limiting nitrification. Soil samples were incubated at 30 2°C for 20 days using vessels with or without the arrangement for trapping CO2 in sodium hydroxide. This arrangement led to a decrease of ca. 96% in the CO2 concentration of the headspace, with a range of 95.7-97.5 at different sampling intervals. In the absence of trapping arrangement, CO 2 concentration of the headspace varied from 580 to 859 ppm, i.e. 62-140% higher than that of the outside atmosphere (358 ppm). The nitrification process was significantly retarded under conditions of reduced CO2 concentration; reduction varied from 8 to 62% at different incubation intervals. The results of the study led to the inference that decreased availability of CO2 in closed vessels (with arrangement for trapping CO2 ) will have a significant bearing on the process of nitrification and hence on the overall dynamics of N transformations. © 2005 Elsevier Ltd. All rights reserved. 1743 Availability of urea to autotrophic ammonia-oxidizing bacteria as related to the fate of 14 C- and 15 N-labeled urea added to soil Marsh K.L., Sims G.K. and Mulvaney R.L. Biology and Fertility of Soils 2005 42/2 (137-145) Nitrate has been found to accumulate more rapidly in soils fertilized with urea than with inorganic sources of NH4 + , despite the fact that nitrification must be preceded by hydrolytic decomposition. For acidic conditions, this finding has been attributed to limited uptake of NH 4 + by ammonium-oxidizing bacteria (also reported herein), suggesting an advantage for direct utilization of a nonionizable N substrate such as urea. If the same advantage applies to urea-C, nitrification of urea-N would also be promoted in neutral or alkaline soils, as reported in numerous studies. To ascertain whether urea-C can be utilized directly by nitrifying organisms, NO2 - production was measured for Nitrosomonas europaea and Nitrosospira sp. NPAV in minimal media with urea as the sole source of either C or C and N. Nitrite accumulated only with the latter organism, in which case nearly quantitative recovery was observed for N added as NH 4 + and/or urea. In a subsequent study, recovery of 14 C and 15 N in gaseous, extractable, and hydrolyzable forms was determined after incubation with labeled urea for up to 29 days, by using two soils that differed markedly in physiochemical properties affecting nutrient availability. Results obtained in correlating 14 C incorporation in the amino acid fraction with 15 N accumulation as NO3 - were consistent with the stoichiometry that would be expected if C fixation were driven by autotrophic nitrification. Our findings demonstrate unequivocally that urea is utilized as a source of SOILS C and N by nitrifying microorganisms, which may account for rapid nitrification of urea-N in soils. 1744 Effects of previous elemental sulfur applications on oxidation of additional applied elemental sulfur in soils Li S., Lin B. and Zhou W. Biology and Fertility of Soils 2005 42/2 (146-152) Oxidation of elemental sulfur (S0 ) in 20 Chinese agricultural soils was tested and the effects of previous S0 applications on the oxidation of additional applied S0 in selected soils were investigated using laboratory, greenhouse, and field experiments. Results showed that sulfur oxidative capacities presented great variability among 20 tested soils, with a coefficient of variation of 92.4%. There were no significant relationships between S0 oxidation and physical and chemical properties of the selected soil. Previous S0 amendment significantly increased the oxidation rate of additional applied S0 . These stimulatory effects after the first applications of S0 were greater than those after two applications. The percent increase in S0 oxidation rate due to S0 pretreatment was negatively correlated with the oxidation capacities of soils before S0 pretreatments. The significant reduction of sulfur oxidation in autoclaved soils and significant increase in S0 oxidation after inoculation with S0 -treated soil suspension demonstrated that microbial oxidation was mainly responsible for the enhancement of soil oxidation ability after previous S0 amendments. 1745 The relation between the content of organic phosphorus and latitude in Northeast China phaeozem Yu W., Zhao S., Zhang L. et al. Biology and Fertility of Soils 2005 42/2 (159-162) Top phaeozem samples were collected from Nenjiang County (in Heilongjiang province) to Changtu County (in Liaoning province) in Northeast China every 6 km by using global positioning system (GPS) and analyzed for their content of organic C, total N, total P, organic P, and the organic to inorganic P (P o /Pi ) ratio. The content of organic P was significantly correlated with organic C and total N contents (P<0.01). The contents of organic P and total P and the Po /Pi ratio were significantly correlated with latitude (P<0.01), with r 2 coefficient of 0.59, 0.46, and 0.36, respectively. Since inorganic P content was not correlated with latitude (r 2 =0.07) and the contents of organic P and total P were significantly correlated (P<0.01, r 2 =0.70), it is reasonable to hypothesize that organic P can play an important role in the spatial differentiation of total P and the Po /Pi ratio. Probably, the causes of these spatial differentiations were the effects of climate and reclamation variations along the North-South transect. 1746 Base-cation cycling by individual tree species in oldgrowth forests of Upper Michigan, USA Fujinuma R., Bockheim J. and Balster N. Biogeochemistry 2005 74/3 (357-376) The influence of individual tree species on base-cation (Ca, Mg, K, Na) distribution and cycling was examined in sugar maple (Acer saccharum Marsh.), basswood (Tilia americana L.), and hemlock (Tsuga canadensis L.) in old-growth northern hardwood - hemlock forests on a sandy, mixed, frigid, Typic Haplorthod over two growing seasons in northwestern Michigan. Base cations in biomass, forest floor, and mineral soil (0-15 cm and 15-40 cm) pools were estimated for five replicated trees of each species; measured fluxes included bulk precipitation, throughfall, stemflow, litterfall, forest-floor leachate, mineralization + weathering, shallow-soil leachate, and deep-soil leachate. The three species differed in where base cations had accumulated within the single-tree ecosystems. Within these three single-tree ecosystems, the greatest quantity of base cations in woody biomass was found in sugar maple, whereas hemlock and basswood displayed the greatest amount in the upper 40 cm of mineral soil. Base-cation pools were ranked: sugar maple > basswood, hemlock in woody biomass; sugar maple, basswood > hemlock in foliage; hemlock > sugar maple, basswood in the forest floor, and basswood > sugar maple, hemlock in the mineral soil. Basecation fluxes in throughfall, stemflow, the forest-floor leachate, and the deep-soil leachate (2000 only) were ranked: basswood > sugar maple > hemlock. Our measurements suggest that species-related differences in nutrient cycling are sufficient to produce significant differences in base-cation contents of the soil 333 over short time intervals (<65 years). Moreover, these speciesmediated differences may be important controls over the spatial pattern and edaphic processes of northern hardwood-hemlock ecosystems in the upper Great Lakes region. © Springer 2005. 1747 Effect of water content on kinetics of volatile organic compounds mass transfer between gas and aqueous phases during gas transport in unsaturated sand Kim H., Annable M.D. and Rao P.S.C. Soil Science 2005 170/9 (680-691) The effect of changing water content on the air-water mass transfer kinetics of volatile organic compounds (VOCs) during gas transport in unsaturated sand was investigated. The kinetics of VOC adsorption at the air-water interface from the gas phase was explored using n-decane, whereas methylene chloride was used to examine the effect of air-water partitioning. Methane was used as the nonreactive tracer in VOC transport experiments conducted using a sand column installed in a gas chromatography system. The longitudinal dispersion of methane, estimated from methane breakthrough curve (BTC), was found to be constant in the water content range (0.07 to 0.18) examined in this study at a constant pore-gas velocity ( g ), whereas an inverse proportionality between the longitudinal dispersion and g was observed. The BTCs for methane and n-decane, measured at constant g , were fairly symmetric, indicating that both gas diffusion and adsorption at air-water interfaces do not produce nonequilibrium transport. The shape of the methylene chloride BTC was gradually distorted at a constant g as water content increased. Fitting methylene chloride BTCs with a modified two-region model showed that the water partitioning becomes more rate-limited as water content increases. The overall mass transfer coefficient for water partitioning of methylene chloride was found to be a direct function of specific air-water interfacial area. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1748 Phosphate sorption by Thai red oxisols and red ultisols Trakoonyingcharoen P., Kheoruenromne I., Suddhiprakarn A. and Gilkes R.J. Soil Science 2005 170/9 (716-725) Phosphate sorption characteristics of 28 samples of red Oxisols and red Ultisols from agricultural areas of Thailand were described by using Langmuir and Freundlich equations. The soils were three Typic Kandiudults, a Typic Paleustult, a Typic Kandiustult, a Typic Kandiustox, three Rhodic Kandiustox, two Rhodic Kandiudox, two Typic Kandiudox, and a Kandiudalfic Eutrudox. Values of Langmuir P maximum (Xm ) ranged from 18 to 1111 mg kg-1 soil and the Freundlich k coefficient varied between 9 and 652 mg kg -1 . Many soil properties were closely correlated with these measures of P sorption capacity including total titanium, goethite, total iron, amorphous aluminum, and specific surface area. Goethite, microcrystalline kaolin, and amorphous forms of Fe and Al oxides were major contributors to P sorption by these soils. The Freundlich B coefficient, which is a measure of P bonding energy, was weakly related to clay content but there were no close relationships between the equivalent Langmuir b coefficient and soil properties. Soil pH in 1 M NaF (pH 8.0) was highly predictive of P sorption and may therefore be used as a quick economical field test for evaluating P fertilizer requirement. Copyright © 2005 by Lippincott Williams & Wilkins. 1749 Low-molecular-weight organic acid exudation of rape (Brassica campestris) roots in cesium-contaminated soils Po N.C., Wang M.K., Jeng J.W. and Chiu C.- Y. Soil Science 2005 170/9 (726-733) Cesium is an emission element from nuclear energy generation easily transferred to food chain. More evidence has been found that Brassica crops take up pollutants from soils. The objective of this study was to investigate the correlation between soil bioavailability of cesium and low-molecular-weight organic acids (LMWOAs) in rape (Brassica campestris) root exudates. Longtan (LT) red (Typic Hapladox) and Kuanshan (KS) iron-rich calcareous soils (Typic Paleudalf) were collected for this study. The pot experiments of rape were conducted with cesium-amended soils and plants grown in the soils (4 weeks). Cesium concentration in shoots and roots correlated well with Cs concentration in the amended soils. Within the amended range of 50 to 300 mg Cs kg -1 soil, Cs did not inhibit rape growth. The bioaccumulation 334 SOILS ratio ([Cs]root /[Cs]soil ] or [Cs]shoot /[Cs] soil ) for Cs in shoots of pot grown plants ranged between 9 and 31 and showed significant differences (P < 0.05). Plant roots can exude LMWOAs, which are important components in root exudation. The total amounts of volatile and nonvolatile LMWOAs in all Cs-amended soils were higher than those in nonamended soils. Meanwhile, the LMWOA concentrations of the rape root exudates showed good correlation with Cs concentrations in the applied range of 50 to 300 mg Cs kg-1 soil. Copyright © 2005 by Lippincott Williams & Wilkins. 1750 Temperature effects on iron reduction in a hydric soil Rabenhorst M.C. and Castenson K.L. Soil Science 2005 170/9 (734-742) For soils to be considered hydric, they must demonstrate both saturation and anaerobic conditions in the upper part of the soil. Although several technologies are available for monitoring of soil water tables, documentation of reducing conditions is more problematic. This has led to recent interest in the use of IRIS (indicator of reduction in soils) tubes. IRIS tubes are lengths of PVC pipe coated with ferrihydrite paint, which are inserted into the soil to document reducing conditions. Observations from preliminary studies led us to postulate soil temperature will affect the degree and rate of reduction and removal of ferrihydrite from the IRIS tubes. To quantify the impact of soil temperature on ferrihydrite reduction and removal from IRIS tubes, a time series experiment was designed such that IRIS tubes were placed into a hydric soil for time periods ranging from 7 to 28 days, between February and June, 2004. Water tables were monitored daily, Eh was measured at depths of 10, 20, 30, 40 and 50, cm on a weekly basis, and soil temperature was recorded every 4 hours. Removal of ferrihydrite from IRIS tubes was not constant during periods of anaerobiosis and was related to soil temperature. At temperatures below 2°C, there was essentially no measurable ferrihydrite reduction, even though soil redox potentials fell within the Fe(II) stability field. As soil temperatures increased between 2 and 8°C, the quantity of ferrihydrite reduction increased with time. At soil temperatures between 8 and 20°C, substantial (35% to 45%) ferrihydrite paint was reduced and removed from IRIS tubes within 7 days. For a given temperature, there was greater reduction of ferrihydrite in zones closer to the soil surface, presumably due to higher amounts of oxidizable organic matter in near surface horizons. Copyright © 2005 by Lippincott Williams & Wilkins. 1751 Mobility of natural radionuclides and selected major and trace elements along a soil toposequence in the Central Spanish Pyrenees Navas A., Machn J. and Soto J. Soil Science 2005 170/9 (743757) Natural gamma-emitting radionuclides (238 U, 226 Ra, 232 Th, 210 Pb) and selected major and trace elements (Ca, K, Mg, Na, Fe, Al, Mn, Pb, Ba, Zn, Sr, Li, Co, Ni, Cu, Cr, Cd) were determined in a soil toposequence along a mountain slope of the Tertiary Flysch landscapes in the Central Spanish Pyrenees. A variety of basic properties were also measured from the soil profiles. Mean radioisotope activities (Bq kg -1 ) range from 22 to 33 for 238 U; 25 to 32 for 226 Ra; 23 to 33 for 210 Pb, and 37 to 46 for 232 Th. The radionuclides showed different patterns in their depth distribution, thus U and Pb had largest differences in concentrations down the soil profiles, whereas 226 Ra and 232 Th exhibited uniform depth distributions. 238 U was depleted in all upper soil layers and enriched in deeper layers. Pb exhibits very different depth profiles along the soil toposequence and accumulated at upper layers in three sites. 238 U/226 Ra activity ratios indicate disequilibrium in the 238 U decay chain and reflect the leaching of 238 U in contrast with the lack of mobility of 226 Ra. The values of 232 Th/226 Ra indicate that the initial proportionality in the 238 U and 232 Th decay chains has not been maintained in this toposequence. The relationships between soil properties and gamma-emitting radionuclides suggested the association of 226 Ra and 232 Th with Fe and Mn oxides. Al, Ca, Fe, and K were the most abundant elements, followed by Mn, Ba, Pb, Sr, Li, and Zn, whereas Co, Cu, Ni, and Cr are as trace elements and Cd was not detected. Correlations between elements suggest association with carbonates (Ca, Sr), silicates and clay minerals (Al, K, Na) and with Fe and Mn oxides (Cr, Cu, Ni, Co, Zn). Along the soil toposequence, Ca, Sr, Mg and Na, K, Al increase at the bottom slope positions, due to highest carbonate contents and abundance of finer soil fractions (clay and silt), respectively. Fe and Mn decrease at the bottom slope because highest contents of Fe and Mn oxides are at upper slope positions. This research is of interest to describe the geochemical cycling of elements in the environment and to assess the processes that affect their mobility in the ecosystems. Copyright © 2005 by Lippincott Williams & Wilkins. 1752 Modeling the effects of gas phase CO2 intrusion on the biogeochemistry of variably saturated soils Altevogt A.S. and Jaffe P.R. Water Resources Research 2005 41/9 (1-9) [1] The transport of gas phase carbon dioxide through unsaturated soils has the potential to significantly alter the soil biogeochemistry. Leakage of CO2 from deep reservoirs, either naturally occurring or anthropogenically emplaced, may displace oxygen in the soil gas and hence radically alter the redox conditions of a soil. Furthermore, the formation of carbonic acid in the aqueous phase will alter the pH of the soil system. A two-dimensional numerical model has been developed to explore the effects of gaseous CO2 leakage on the biogeochemistry of a variably saturated porous media. The model describes the sequential degradation of organic carbon by microorganisms using a series of terminal electron acceptors. Gas phase CO2 intrusion results in changes in redox conditions and pH of the soil water, both of which lead to alteration of the biogeochemistry of the soil. Alteration of the biogeochemical profile of a representative field site is explored with the numerical model. Copyright 2005 by the American Geophysical Union. 1753 Selenium distribution in topsoils and plants of a semiarid Mediterranean environment Moreno Rodriguez M.J., Cala Rivero V. and Jim´enez Ballesta R. Environmental Geochemistry and Health 2005 27/5-6 (513-519) Selenium was determined from 25 topsoils and 25 plants in the semi-arid Central Spain where large extents of soils are developed on evaporitic materials. Some species of vegetation associated with them are of the genera Astragalus, Salsola, Mercurialis, Phlomis, Thymus and Atriplex. Total selenium in soils was determined and its bioavailability assessed by chemical sequential fractionation. Se content in soils was adequate (in the range 0.17-0.39 mg kg-1 ) or large (in the range 0.50-4.38 mg kg-1 ) and appeared in highly and/or potentially available forms. Several plant species showed high Se levels (in the range 5-14.3 mg kg-1 ), which can be a potential risk of toxicity to animals. Data obtained from the study area can be used as a guide to the range of values in soils and plants of the European Mediterranean area that are relatively unpolluted from industrial sources, allowing comparison with more polluted areas. © Springer 2005. 1754 Uranium accumulation of crop plants enhanced by citric acid Chang P., Kim K.- W., Yoshida S. and Kim S.- Y. Environmental Geochemistry and Health 2005 27/5-6 (529-538) Citric acid was applied to soil to enhance U accumulation in four crop plants. While the highest enhanced U accumulation of aboveground tissues (a.c. 2000 mg kg-1 dry weight) occurred in the leaves of Indian mustard (Brassica juncea), the highest enhanced U accumulation of roots (a.c. 3500 mg kg-1 dry weight) occurred in canola (Brassica napus var. napus). Uranium translocation among tissues of test plants is in the relation of roots > shoots = leaves. The flowers of sunflower (Helianthus annuus) contained similar or higher U concentrations than those found in shoots, but concentrations in seeds are close to zero. In conclusion, Indian mustard is recommended as a potential species for phytoextraction for U-contaminated soil due to its high U accumulation of aboveground biomass (a.c. 2200 g per plant). There is no evidence that two types of soils cause a significant difference of the enhanced U accumulation (p<0.05). Results, however, indicate that additional citric acid may result in downward U migration that may contaminate groundwater. Speciation of U that is taken up by plants is also discussed in the end. © Springer 2005. SOILS 222 Rn activity concentration in soil gas at 1755 Variation of a site in Sapporo, Japan Fujiyoshi R., Kinoshita M. and Sawamura S. Environmental Geochemistry and Health 2005 27/5-6 (539-547) Several factors controlling the soil radon level in the present site were found to be changing air-filled porosity caused by fluctuations in moisture content, differences between the atmospheric and soil temperatures as well as volumetric 226 Ra content of the soil. The radon activity increased significantly in early October, especially at point 1, possibly as a result of a magnitude 8.0 earthquake which occurred on September 26, 2003, with epicenter located offshore near Tokachi, Hokkaido. © Springer 2005. 1756 The impact of the hyperacid Ijen Crater Lake. Part I: Concentrations of elements in crops and soil Heikens A., Widianarko B., Dewi I.C. et al. Environmental Geochemistry and Health 2005 27/5-6 (409-418) In Asembagus (East Java, Indonesia) irrigation water is contaminated with effluent from the hyperacid Ijen Crater Lake resulting in a low pH and high levels of various elements. As a first step towards a risk assessment, locally produced food items (rice, maize, cassava leaf, cassava root, peanuts) were collected and concentrations of As, B, Ca, Cd, Co, Cu, Fe, Mg, Mn, Mo, Ni, Pb, V, Zn were compared to samples from a reference area and with literature values. Further, concentrations in rice were compared to total soil concentrations in paddy fields. Compared to the reference area, food items produced in the contaminated area had increased levels of Cd, Co, Ni and Mn in particular, while levels of Mo were lower. In contrast, total soil concentrations of Cd and Mn in particular have decreased whereas especially Mo was increased. In combination with the observed soil acidification, it is likely that the bioavailable concentration of most elements in the contaminated soil is higher (except for Mo) due to an increased weathering rate and/or input via the contaminated irrigation water. In terms of human health, concentrations in foods were generally within normal literature values. However, it was observed that essential elements (in particular Fe) known for their inhibitory effects on e.g. Cd and Mn toxicity did not accumulate in crops whereas Cd and Mn did. © Springer 2005. 1757 Effect of sewage sludge or compost on the sorption and distribution of copper and cadmium in soil Vaca- Pauln R., Esteller- Alberich M.V., Lugo- De La Fuente J. and Zavaleta- Mancera H.A. Waste Management 2006 26/1 (71-81) The application of biosolids such as sewage sludge is a concern, because of the potential release of toxic metals after decomposition of the organic matter. The effect of application of sewage sludge (Sw) and compost (C) to the soil (S) on the Cu and Cd sorption, distribution and the quality of the dissolved organic matter (DOM) in the soil, was investigated under controlled conditions. Visible spectrophotometry, infrared spectroscopy, sorption isotherms (simple and competitive sorption systems), and sequential extraction methods were used. The E4 /E6 ( at 465 and 665 nm) ratio and the infrared spectra (IR) of DOM showed an aromatic behaviour in compost-soil (C-S); in contrast sewage sludge-soil (Sw-S) showed an aliphatic behaviour. Application of either Sw or C increased the Cu sorption capacity of soil. The Cd sorption decreased only in soil with a competitive metal system. The availability of Cu was low due to its occurrence in the acid soluble fraction (F3). The Cu concentration varied in accordance with the amounts of Cu added. The highest Cd concentration was found in the exchangeable fraction (F2). The Sw and C applications did not increase the Cd availability in the soil. © 2005 Elsevier Ltd. All rights reserved. 1758 Characterization of phosphorus in sub-alpine forest and adjacent grassland soils by chemical extraction and phosphorus-31 nuclear magnetic resonance spectroscopy Chiu C.- Y., Pai C.- W. and Yang K.- L. Pedobiologia 2005 49/6 (655-663) We used chemical extraction methods and 31 P-nuclear magnetic resonance (NMR) to investigate the effects of vegetation on the amount and structural composition of phosphorous (P) in the sub-alpine soils of central Taiwan. Chemical extraction methods were used to measure inorganic P (Pi) and organic P (Po) in main 335 soil horizons. The soil P composition was assessed by spectroscopy on alkaline EDTA-NaOH extracts. According to the results of chemical extractions, the forest soil had a higher amount of Pi than the grassland soil, which might be a result of the mineralization of Po. 31 P-NMR spectra showed inorganic orthophosphate (up to 67%) and orthophosphate monoesters (up to 75%) as the major forms of P extracted in forest and grassland soils, respectively. Smaller proportions of orthophosphate diesters and trace amounts of phosphonates and pyrophosphate were found. With possible hydrolysis of P compounds during chemical extraction and slight systemic error in the processes of extraction with NMR, the results from NMR analysis are, in general, consistent with those of chemical extraction. © 2005 Elsevier GmbH. All rights reserved. 31 P-NMR 1759 Effects of different ground clearance on soil fertility of Chinese fir stands (Chinese) Xue L., Xiang W., He Y. et al. Chinese Journal of Applied Ecology 2005 16/8 (1417-1421) The study on the soil physical properties, nutrient contents, microbial amounts and enzyme activities of clear cuttting and controlled burning Chinese fir stands showed that in comparing with the control, soil non-capillary porosity of clear cutting stand increased by 23%, whereas soil natural water capacity and capillary moisture capacity decreased by 25%. In controlled burning stand, soil bulk density increased by 10%, while soil noncapillary porosity, natural water capacity and capillary moisture capacity decreased by 61%, 48% and 26%, respectively. The contents of soil organic matter, total N, total P and total K in clear cutting stand decreased by 14%, 14%, 35% and 22%, and in controlled burning stand, they decreased by 37%, 37%, 47% and 7%, respectively. Soil alkalized N and available K in clear cutting stand increased by 24% and 31%, respectively, but soil available P decreased by 15%. The contents of soil alkalized N, available P and available K in controlled burning stand decreased by 25%, 43% and 40%, respectively. In clear cutting stand, the amounts of soil bacteria, fungi and actinomyces increased by 1.4, 11.3 and 0.8 times, respectively, but in controlled burning stand, the amounts of soil bacteria decreased by 24%, while those of soil fungi and actinomyces increased by 5.0 and 0.5 times, respectively. The activities of soil urease, catalase and cellulase in clear cutting stand increased by 1.9, 1.6 and 2.1 times, and in controlled burning land, they were 35%, 90% and 106% of the control, respectively. Damp soil had higher contents of organic matter, total N and total P, whereas porous soil was favorable for the accumulation of alkalized N, available P and available K and for the increase of soil urease activity. The amount of soil fungi decreased with increasing soil capillary porosity. Aerated soil was favorable for the increase of soil catalase activity. 1760 Spatial variability of nutrients in cultivated soils of Xinhui District, Jiangmen City (Chinese) Gan H. and Peng L. Chinese Journal of Applied Ecology 2005 16/8 (1437-1442) Employing geostatistical methods and GIS technology, this paper studied the spatial distribution characteristics of pH, organic matter, CEC, total nitrogen, available phosphorus and slowly available potassium in cultivated soils of Xinhui District, Jiangmen City. All the test variables were normally or log normally distributed. Semivariogram analysis showed that soil nutrients were moderately spatially-dependent in a given spatial range, except that soil total nitrogen was strongly spatially-dependent. It was shown from Kriging analysis that soil pH and CEC was the highest in the northeast, and soil organic matter content was higher in the middle and northeast investigation region. The area with 1.5-2.0 gkg-1 soil total nitrogen content accounted for 75.7 % of the investigated region, mainly distributed in the west and east, that with >40 mgkg-1 soil available phosphorus content was accounted for 48.7%, mainly distributed in the west and northeast, and the area that slowly available potassium content was 160-350 mgkg-1 accounted for 48.1%, mainly distributed in the east, northeast and the middle. 1761 Relationships between red soil enzyme activity and fertility (Chinese) Xue D., Yao H., He Z. and Huang C. Chinese Journal of Applied Ecology 2005 16/8 (1455-1458) 336 SOILS Correlation and cluster analyses on the enzyme activities and chemical-biological properties of eight red soils showed that soil urease, invertase, phosphatase and catalase activities correlated significantly with soil organic carbon, total nitrogen and total phosphorous. Similar results of soil fertility evaluation were obtained by using soil enzyme activities and by using soil chemical-biological properties, indicating that soil enzyme activity could be used as an index of evaluating red soil fertility. The enzyme activities of fresh soil were generally greater than those of air-dried sample, and more closely correlated with soil fertility. Organic matter 1762 Soil carbon stocks and changes in the Republic of Ireland Tomlinson R.W. Journal of Environmental Management 2005 76/1 (77-93) The soil carbon (C) stock of the Republic of Ireland is estimated to have been 2048 Mt in 1990 and 2021 Mt in 2000. Peat holds around 53% of the soil C stock, but on 17% of the land area. The C density of soils (t C ha-1 ) is mapped at 2 km2 km resolution. The greatest soil C densities occur where deep raised bogs are the dominant soil; in these grid squares C density can reach 3000 t C ha-1 . Most of the loss of soil C between 1990 and 2000 - up to 23 Mt C (1% of 1990 soil C stock) - was through industrial peat extraction. The average annual change in soil C stocks from 1990 to 2000 due to land use change was estimated at around 0.02% of the 1990 stock. Considering uncertainties in the data used to calculate soil C stocks and changes, the small average annual ‘loss’ could be regarded as ‘no change’. © 2005 Elsevier Ltd. All rights reserved. 1763 Stock and distribution of total and corn-derived soil organic carbon in aggregate and primary particle fractions for different land use and soil management practices Puget P., Lal R., Izaurralde C. et al. Soil Science 2005 170/4 (256-279) Land use, soil management, and cropping systems affect stock, distribution, and residence time of soil organic carbon (SOC). Therefore, SOC stock and its depth distribution and association with primary and secondary particles were assessed in long-term experiments at the North Appalachian Experimental Watersheds near Coshocton, Ohio, through 13 C techniques. These measurements were made for five land use and soil management treatments: (1) secondary forest, (2) meadow converted from no-till (NT) corn since 1988, (3) continuous NT corn since 1970, (4) continuous NT corn-soybean in rotation with ryegrass since 1984, and (5) conventional plow till (PT) corn since 1984. Soil samples to 70-cm depth were obtained in 2002 in all treatments. Significant differences in soil properties were observed among land use treatments for 0 to 5-cm depth. The SOC concentration (g C kg-1 of soil) in the 0 to 5-cm layer was 44.0 in forest, 24.0 in meadow, 26.1 in NT corn, 19.5 in NT corn-soybean, and 11.1 in PT corn. The fraction of total C in corn residue converted to SOC was 11.9% for NT corn, 10.6% for NT corn-soybean, and 8.3% for PT corn. The proportion of SOC derived from corn residue was 96% for NT corn in the 0 to 5-cm layer, and it decreased gradually with depth and was 50% in PT corn. The mean SOC sequestration rate on conversion from PT to NT was 280 kg C ha-1 y-1 . The SOC concentration decreased with reduction in aggregate size, and macro-aggregates contained 15 to 35% more SOC concentration than microaggregates. In comparison with forest, the magnitude of SOC depletion in the 0 to 30-cm layer was 15.5 Mg C/ha (24.0%) in meadow, 12.7 Mg C/ha (19.8%) in NT corn, 17.3 Mg C/ha (26.8%) in NT corn-soybean, and 23.3 Mg C/ha (35.1%) in PT corn. The SOC had a long turnover time when located deeper in the subsoil. Additional research is needed to understand association of SOC with particle and aggregate size fractions and temporal changes and depth-distribution with regard to land use and soil management. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1764 Soil organic carbon sequestration rates in two longterm no-till experiments in Ohio Jarecki M.K. and Lal R. Soil Science 2005 170/4 (280-291) The effectiveness of no-till (NT) farming in reducing loss of soil organic matter (SOM) depends on climate and soil properties. Soil samples were obtained from two long-term experiments that were designed to study the impact of tillage systems on crop yields. However, the objectives of this experiment were to assess the impact of NT on soil organic carbon (SOC) sequestration rate and other soil properties and to estimate historic depletion of SOC under different soil management practices with reference to the undisturbed wooded control. The two long-term experiments in Ohio studied were those sited at South Charleston and Hoytville. The South Charleston (83° 30 W and 39° 48 N) experiment was established in 1962 on Crosby silt loam (fine mixed, mesic Aeric Ochraqualf). The site has long-term annual temperature and precipitation of 10.8°C and 1043 mm, respectively. Tillage treatments for continuous corn (Zea mays) were NT, chisel plow (CP), and moldboard plow (MP). The Hoytville (84° 04 W and 41° 03 N) experiment was established in 1987 on Hoytville clay loam (fine, illitic mesic Mollic Epiaqualfs) soil. The site has long-term annual temperature and precipitation of 9.9°C and 845 mm, respectively. There were two crop rotations: (i) 2-year corn-soybean (Glycine max) rotation with NT and subsoiling and (ii) 3-year corn-soybean-oat (Avena sativa) rotation with NT, CP, and rotational tillage soil management. The Hoytville clay site is poorly drained, has higher clay content, and higher and more even by distributed antecedent level of SOC in the soil profile than does the South Charleston silt loam soil. No-til increased SOC and N pools in the 0 to 5-cm layer in silt loam soil but had no effect in clay soil. The rate of SOC sequestration in the silt-loam soil under NT was 175 kg C ha-1 y -1 . The silt loam soil had higher SOC and N stratification ratios in NT than in MP and CP treatments, whereas the stratification ratios were low and similar in all treatments in the clayey soil. For both soils, there were no differences between tillage treatments in several soil properties including texture, available water capacity, hydraulic conductivity (Ks ), and cation exchange capacity. The NT decreased soil bulk density and pH in the 0 to 15-cm layer in the silt loam soil. The plow til treatments had a small impact on soil aggregation in clayey soil. The decline in water-stable aggregates with reference to NT was no more than one sixth. In the silt loam soil, however, the water-stable aggregates in plow till treatments were merely one third of that in the NT treatment. The historic loss of the SOC pool for 0 to 30-cm depth under agricultural land use was 25 to 35% in silt loam and 19 to 25% in the clayey soil. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1765 Comparison of odorous volatile compounds from fourteen different commercial composts using solid-phase microextraction Kim H., McConnell L.L. and Millner P. Transactions of the American Society of Agricultural Engineers 2005 48/1 (315-320) In this study, odorous volatile compounds (OVCs) from marketready, commercial composts supplied by 14 different producers were compared using a recently developed method involving solid-phase microextraction (SPME) of headspace volatiles followed by GC analysis. The products analyzed were derived from a cross-section of the wide array of compost feedstock ingredients used in the U.S. (e.g., biosolids, yard trimmings, animal manure, and industrial by-products). A variety of quality assessment tests were performed using test procedures specified in a national certification program offered through the U.S. Composting Council. Measurements of odorous chemicals (i.e., trimethylamine, carbon disulfide, dimethylsulfide, dimethyldisulfide, propionic acid, and butyric acid) supplemented other quality aspects in the evaluation of stability. Result showed that relatively higher concentrations of reduced sulfur-containing compounds were detected from marketable composts containing sewage sludge than from composts produced with other feedstocks. The greatest amounts of reduced sulfur-containing compounds were detected from a compost containing a mixture of industrial sludge and agricultural byproducts. Pathogen indicator microbes for most composts were within limits for Class A (U.S. EPA 40CFR Part503). Very large numbers of fecal coliforms, E. coli, and Enterococcus were present in the compost that produced the greatest concentrations SOILS of carbon disulfide and dimethylsulfide. Composts containing sewage sludge and yard wastes produced relatively higher concentrations of propionic and butyric acids than those containing other ingredients. The composition of OVCs in compost products can be objectively evaluated with the SPME method reported here. Results in combination with other compost quality factors may help compost producers improve product quality. 1766 Phosphorus speciation in manure and manureamended soils using XANES spectroscopy Sato S., Solomon D., Hyland C. et al. Environmental Science and Technology 2005 39/19 (7485-7491) Previous studies suggested an increase in the proportion of calcium phosphates (CaP) of the total phosphorus (P) pool in soils with a long-term poultry manure application history versus those with no or limited application histories. To understand and predict long-term P accumulation and release dynamics in these highly amended soils, it is important to understand what specific P species are being formed. We assessed forms of CaP formed in poultry manure and originally acidic soil in response to different lengths of mostly poultry manure applications using P K-edge X-ray absorption near-edge structure (XANES) spectroscopy. Phosphorus K-edge XANES spectra of poultry manure showed no evidences of crystalline P minerals but dominance of soluble CaP species and free and weakly bound phosphates (aqueous phosphate and phosphate adsorbed on soil minerals). Phosphate in an unamended neighboring forest soil (pH 4.3) was mainly associated with iron (Fe) compounds such as strengite and Feoxides. Soils with a short-term manure history contained both Fe-associated phosphates and soluble CaP species such as dibasic calcium phosphate (DCP) and amorphous calcium phosphate (ACP). Long-term manure application resulted in a dominance of CaP forms confirming our earlier results obtained with sequential extractions, and a transformation from soluble to more stable CaP species such as -tricalcium calcium phosphate (TCP). Even after long-term manure application (>25 yr and total P in soil up to 13 307 mg kg-1 ), however, none of the manure-amended soils showed the presence of crystalline CaP. With a reduction or elimination of poultry manure application to naturally acidic soils, the pH of the soil is likely to decrease, thereby increasing the solubility of Ca-bonded inorganic P minerals. Maintaining a high pH is therefore an important strategy to minimize P leaching in these soils. © 2005 American Chemical Society. 1767 Copper(II) complexation by humic and fulvic acids from pig slurry and amended and non-amended soils Plaza C., Senesi N., Garca- Gil J.C. and Polo A. Chemosphere 2005 61/5 (711-716) The effect of the consecutive annual additions of pig slurry at rates of 0 (control), 90 and 150 m3 ha-1 y-1 over a 4-year period on the binding affinity for Cu(II) of soil humic acids (HAs) and fulvic acids (FAs) was investigated in a field plot experiment under semiarid conditions. A ligand potentiometric titration method and a single site model were used for determining the Cu(II) complexing capacities and the stability constants of Cu(II) complexes of HAs and FAs isolated from pig slurry and control and amended soils. The HAs complexing capacities and stability constants were larger than those of the corresponding FA fractions. With respect to the control soil HA, pig-slurry HA was characterized by a much smaller binding capacity and stability constant. Amendment with pig slurry decreased the binding affinity of soil HAs. Similar to the corresponding HAs, the binding affinity of pig-slurry FA was much smaller while that of amended-soil FAs were slightly smaller when compared to the control soil FA. The latter effect was, however, more evident with increasing the amount of pig slurry applied to soil per year and the number of years of pig slurry application. © 2005 Elsevier Ltd. All rights reserved. 1768 Leaf litter decomposition in a chaparral ecosystem, Southern California Quideau S.A., Graham R.C., Oh S.- W. et al. Soil Biology and Biochemistry 2005 37/11 (1988-1998) Decomposition losses from leaves of three evergreen chaparral species, scrub oak (Quercus dumosa), ceanothus (Ceanothus crassifolius), and manzanita (Arctostaphylos glauca), were quantified over a 2-y field exposure using litterbags. Changes in 337 ash-free dry mass, C, and N were monitored at 2- to 6-month intervals at four replicate sites composed of patches of these three chaparral species. Three proximate C fractions were extracted from fresh and decomposing litter samples: polar and non-polar extractives (EXT), acid-solubles (ACID), and acid-insolubles (KLIG). The chemical structure of fresh and decomposed litter was additionally characterized using high-resolution solid-state 13 C NMR spectroscopy, while morphological properties were examined by scanning electron microscopy (SEM). After 2 y, the litters had lost between 20.7% 1.2 (Ceanothus) and 35.2% 6.8 (Quercus) of their original ash-free dry mass. The manzanita decomposed at a significantly faster rate than the other two litter types during the first few months of field exposure. Yet, after 2 y, mass loss was greater for the oak. Differences in decomposition rates could not be accounted for based on a single litter quality index. Fresh manzanita exhibited a significantly higher N content, which could explain its initially faster decay rate. Fresh oak litter, on the other hand, had a relatively high ACID and O-alkyl C (O-ALK) content, which may have been responsible for its decay pattern. Fresh ceanothus contained a relatively low KLIG content, yet it decomposed more slowly than the two other species. The solid-state 13 C NMR spectra of the ceanothus litter had two peaks characteristic of proanthocyanidins, which likely contributed to the recalcitrance of this litter type. SEM revealed that ceanothus leaf surfaces were left nearly unchanged after field exposure. In comparison, the oak and manzanita leaf surfaces were pitted and covered by microbial growth to the point of being unrecognizable. Taken together, our results indicate that a combination of biological, physical and chemical factors need to be examined to clarify the different decomposition rates and patterns of these three chaparral species. © 2005 Elsevier Ltd. All rights reserved. 1769 Long-term application of organic manure and nitrogen fertilizer on N 2 O emissions, soil quality and crop production in a sandy loam soil Meng L., Ding W. and Cai Z. Soil Biology and Biochemistry 2005 37/11 (2037-2045) A long-term field experiment was established to determine the influence of mineral fertilizer (NPK) or organic manure (composed of wheat straw, oil cake and cottonseed cake) on soil fertility. A tract of calcareous fluvo-aquic soil (aquic inceptisol) in the Fengqiu State Key Experimental Station for Ecological Agriculture (Fengqiu county, Henan province, China) was fertilized beginning in September 1989 and N2 O emissions were examined during the maize and wheat growth seasons of 2002-2003. The study involved seven treatments: organic manure (OM), halforganic manure plus half-fertilizer N (1/2 OMN), fertilizer NPK (NPK), fertilizer NP (NP), fertilizer NK (NK), fertilizer PK (PK) and control (CK). Manured soils had higher organic C and N contents, but lower pH and bulk densities than soils receiving the various mineralized fertilizers especially those lacking P, indicating that long-term application of manures could efficiently prevent the leaching of applied N from and increase N content in the plowed layer. The application of manures and fertilizers at a rate of 300 kg N ha-1 year-1 significantly increased N2 O emissions from 150 g N2 O-N ha-1 year-1 in the CK treatment soil to 856 g N2 O-N ha-1 year-1 in the OM treatment soil; however, there was no significant difference between the effect of fertilizer and manure on N2 O emission. More N2 O was released during the 102-day maize growth season than during the 236-day wheat growth season in the N-fertilized soils but not in N-unfertilized soils. N2 O emission was significantly affected by soil moisture during the maize growth season and by soil temperature during the wheat growth season. In sum, this study showed that manure added to a soil tested did not result in greater N2 O emission than treatment with a N-containing fertilizer, but did confer greater benefits for soil fertility and the environment. © 2005 Elsevier Ltd. All rights reserved. 1770 Dissolved organic carbon (DOC) as a parameter of compost maturity Zmora- Nahum S., Markovitch O., Tarchitzky J. and Chen Y. Soil Biology and Biochemistry 2005 37/11 (2109-2116) Despite numerous investigations of the maturation process of composts, a simple and straightforward parameter which can 338 SOILS predict plant response upon compost application has yet to be defined. In light of results accumulated over a decade, we examined simple, chemical parameters of three composts from three types of source materials (municipal solid waste (MSW), separated cow manure (CSM), biosolids (BS)). These materials were composted using different procedures and facilities. The chemical parameters were correlated to the growth response of cucumbers or ryegrass sown in potting media amended with the composts sampled at different stages of the process. The dissolved organic carbon (DOC) concentration of all composts decreased rapidly within the first month, then, towards the end of the process, stabilized at concentration below 4 g kg-1 . DOC correlated highly and significantly to the absorbance at 465 nm in all composts, and also to the C/N ratio. Nitrate evolution was similar in all composts, but the final concentrations differed among them. Plant biomass increased with composting time. For CSM and BS compost maximum biomass was reached when the DOC reached levels below 4 g kg-1 . DOC concentration is suggested for use as a simple method of determining maturity, with 4 g kg-1 recommended as a threshold level indicating maturity. Absorbance at 465 nm can be used instead of DOC concentration after appropriate calibration. © 2005 Elsevier Ltd. All rights reserved. 1773 Humus accumulation and microbial activities in calcari-epigleyic fluvisols under grassland and forest diked in for 30 years Dilly O., Gnafl A. and Pfeiffer E.- M. Soil Biology and Biochemistry 2005 37/11 (2163-2166) The accumulation and transformation of organic matter during soil development is rarely investigated although such processes are relevant when discussing about carbon sequestration in soil. Here, we investigated soils under grassland and forest close to the North Sea that began its genesis under terrestrial conditions 30 years ago after dikes were closed. Organic C contents of up to 99 mg g-1 soil were found until 6 cm soil depth. The humus consisted mainly of the fraction lighter than 1.6 g cm-3 which refers to poorly degraded organic carbon. High microbial respiratory activity was determined with values between 1.57 and 1.17 g CO2 -C g -1 soil h-1 at 22°C and 40 to 70% water-holding capacity for the grassland and forest topsoils, respectively. The microbial C to organic C ratio showed values up to 20 mg Cmic g-1 C org . Although up to 2.69 kg C m-2 were estimated to be sequestered during 30 years, the microbial indicators showed intensive colonisation and high transformation rates under both forest and grassland which were higher than those determined in agricultural and forest topsoils in Northern Germany. © 2005 Elsevier Ltd. All rights reserved. 1771 Improving quality of composted biowaste to enhance disease suppressiveness of compost-amended, peat-based potting mixes Veeken A.H.M., Blok W.J., Curci F. et al. Soil Biology and Biochemistry 2005 37/11 (2131-2140) Biowaste can be converted into compost by composting or by a combination of anaerobic digestion and composting. Currently, waste management systems are primarily focused on the increase of the turnover rate of waste streams whereas optimisation of product quality receives less attention. This results in low quality composts that can only be sold on bulk markets at low prices. A new market for quality compost could be potting mixes for horticultural container-grown crops to partially replace non-renewable peat and increase the disease suppressiveness of potting mixes. We report here on the effect of wetsieving biowaste prior to composting on compost quality and on disease suppressiveness against the plant pathogen Pythium ultimum of peat mixes amended with this compost. The increased organic matter and decreased salt content of the compost allow for significantly higher substitution rates of peat by compost. In this study up to 60% v/v compost peat replacement did not affect cucumber growth. However, disease suppressiveness of the potting mixes strongly increased from 31 to 94% when the compost amendment rate was increased from 20 to 60%. It was shown that general disease suppression for P. ultimum can only be effective when the basal respiration rate is sufficiently high to support microbial activity. In addition, organic matter of the compost should reach a sufficient stability level to turn from disease conducive to disease suppressive. Increasing the compost addition from 20 to 60% did not significantly affect plant yield, yield variation were due to differences in nutrient levels. It can be concluded that compost from wetsieved biowaste has high potential to replace peat in growing media for the professional market. © 2005 Elsevier Ltd. All rights reserved. 1774 Organic N forms of a subtropical Acrisol under no-till cropping systems as assessed by acid hydrolysis and solidstate NMR spectroscopy Dieckow J., Mielniczuk J., Knicker H. et al. Biology and Fertility of Soils 2005 42/2 (153-158) This study was conducted to investigate the influence of landuse systems (grassland and cropland) and of long-term no-till cropping systems [bare soil, oat/maize (O/M), pigeon pea+maize (P+M)] on the composition of organic N forms in a subtropical Acrisol. Soil samples collected from the 0- to 2.5-cm layer in the study area (Eldorado do Sul RS, Brazil) were submitted to acid hydrolysis and cross-polarization magic angle spinning (CPMAS) 15 N and 13 C nuclear magnetic resonance (NMR) spectroscopies. The legume-based cropping system P+M contained the highest contents of non-hydrolysable C and N, hydrolysable C and N, amino acid N and hydrolysed unknown N. The relative proportion of non-hydrolysable N was higher in bare soil (30.0%) and decreased incrementally in other treatments based on the total C and N contents. The amino acid N corresponded to an average of 37.2% of total N, and was not affected by land use and notill cropping systems. The non-hydrolysable residue contained lower O-alkyl and higher aromatic C concentrations, as revealed by CPMAS 13 C NMR spectroscopy, and higher C:N ratio than the bulk soil. No differences in the bulk soil organic matter composition could be detected among treatments, according to CPMAS 13 C and 15 N NMR spectra. In the non-hydrolysable fraction, grassland showed a lower concentration of aromatic and a higher concentration of alkyl C than other treatments. From CPMAS 15 N NMR spectra, it could be concluded that amide N from peptide structures are the main organic N constituent. Amide structures are possibly protected through encapsulation into hydrophobic sites of organic matter and through organomineral interaction. 1772 Soil nitrogen cycling under litter and coarse woody debris in a mixed forest in New York State Hafner S.D. and Groffman P.M. Soil Biology and Biochemistry 2005 37/11 (2159-2162) Coarse woody debris (CWD) could alter N availability and transformations in the underlying soil and therefore contribute to spatial heterogeneity and influence ecosystem loss of N. We measured soil N concentrations and transformations in soil beneath CWD and beneath a litter layer at a mixed forest in NY State. We found that total and microbial biomass N was lower and that microbial biomass C-to-N ratio was higher in soil beneath CWD. Rates of N 2 O production and denitrification enzyme activity were reduced beneath CWD. These results suggest that CWD is an important controller of spatial heterogeneity in N dynamics and may influence the magnitude of N loss in temperate forests. © 2005 Elsevier Ltd. All rights reserved. 1775 Effect of humic amendments on inorganic N, dehydrogenase and alkaline phosphatase activities of a Mediterranean soil Lizarazo L.M., Jord´a J.D., Ju´arez M. and S´anchez- Andreu J. Biology and Fertility of Soils 2005 42/2 (172-177) Dehydrogenase activity, alkaline phosphatase activity and NH4 + , NO - and NO - concentrations were monitored in an aridisol 2 3 treated with three commercially available humic amendments. The materials were of plant residue, lignite and peat origins. The humus plant residues, fulvic acids, with a high content of Kjeldahl-N, sustained high enzyme activities and highest levels of NH 4 + , NO2 - and NO3 - . Humus lignite (mainly humic acids) produced the highest dehydrogenase activity, whereas the alkaline phosphatase activity was not as high as that amendment with humus plant residues. The lower activity of alkaline phosphatase could not be attributed to the higher P content of humus lignite. Nitrification was also low, probably due to the low N content of this fertilizer. The amendment of humus peat origin SOILS (only humic acids) did not increase enzyme activity or inorganic N concentrations of soil. Our results show that although these materials are widely utilized and recommended as microbial and plant activators, they all behave very differently, and the effects on soil microbiological activity cannot be predicted solely on the basis of their humic and/or fulvic acid contents. 1776 Degradation and preservation of vascular plant-derived biomarkers in grassland and forest soils from Western Canada Otto A. and Simpson M.J. Biogeochemistry 2005 74/3 (377-409) The total solvent extracts (TSE) of mineral and organic horizons of selected soils and overlying vegetation were analyzed using gas chromatography-mass spectrometry (GC-MS) to determine the composition of solvent-extractable (‘free’) lipids in soils and to study the degradation and possible preservation of vascular plant-derived molecular markers (biomarkers) in soils. Major compound classes in the TSE of soils and vegetation included a homologous series of aliphatic lipids (alkanoic acids, alkanols, alkanes), steroids, and terpenoids. Characteristic patterns of aliphatic and cyclic biomarkers derived from the overlying, native vegetation were recognized in the associated soil samples indicating the preservation of lipids from the external waxes of vascular plants in the soil organic matter (SOM). The observed biomarker patterns in the grassland soils (Brown Chernozems) were similar to the compounds identified in their major source vegetation, Western Wheatgrass. A similar composition of biomarkers was observed in Aspen leaves and the soil horizons of the forestgrassland transition soil (Dark Gray Chernozem). The Lodgepole Pine needles yielded a characteristic pattern of diterpenoids that was also detected in leaf litter and the O horizon of the associated forest soil (Brunisol). The results demonstrate that solvent extractable biomarkers derived from vascular plants maintain their characteristic pattern of aliphatic and cyclic lipids despite ongoing degradation processes and are thus valuable molecular markers for the determination of the sources of SOM. Furthermore, the abundance of aliphatic wax lipids in plant material and soils decreased at higher rates than the steroids and terpenoids indicating the preferential degradation of aliphatic over cyclic biomarkers. Most of the plant-derived steroids and terpenoids identified in the soils were unaltered, preserved biomolecules as observed in the source vegetation, but minor amounts of their degradation products were also present. Oxidation products of plant sterols are reported here for the first time in soils. The detected alteration products of steroids and diterpenoids are consistent with the oxidative degradation of free cyclic biomarkers in decomposing plant material and soils. © Springer 2005. 1777 Fate of the metal-binding soluble organic matter throughout a soil profile Dudal Y., S´evenier G., Dupont L. and Guillon E. Soil Science 2005 170/9 (707-715) Crop residues are a major source of soluble organic matter (SOM) in agricultural soils. The fate of this complex mixture of organic compounds is mainly controlled by the biodegradation by soil microbes, sorption to the different soil surfaces, and transfer through the soil profile along with the water flow. During this transfer, the soluble organic matter can bind micropollutants such as metals and co-transport them down the soil profile to the groundwater. However, monitoring usually consists in measuring the organic content of the aqueous sample (dissolved or water-soluble organic matter), rarely its reactivity. The objective of this study was to monitor both the SOM content and its reactivity toward metal cations during its transport through the soil. Therefore, samples were collected from a field experiment performed on a 2-m-deep vadose zone over a 7-month period. The metal-binding capacity of 84 of these samples was quantified for Cu2+ , Fe2+ , and Mn 2+ , using the quenching of SOM fluorescence that is observed when increasing concentrations of metal cations are added to the SOM sample. A simple Langmuir-type model was used to quantify the three binding constants for each SOM sample and the amount of metal that it can bind. This method gives binding constants for SOM with each metal cation that respect the general observations made for natural organic matter (log K = 5.31, 4.79, and 4.77 for Cu 2+ , Fe2+ and Mn2+ , respectively, for a surface soil sample). Although the SOM content decreased from 10 to 2 mg L-1 over the 2-m-deep vadose zone, the profile 339 of the overall complexation constant was homogeneous (log K = 5.36 0.05 for Cu2+ ), indicating that only a small portion of the SOM was responsible for metal binding. The influence of environmental parameters such as residue incorporation, soil temperature, and rainfall events on the amount of metals that SOM can bind was assessed. Strong rainfall events were able to transport a limited amount of metal-binding SOM (up to 1 M Cu2+ per sample), even in the case where very low organic matter content was found. The freeze-thaw cycle liberated much more metal-binding SOM (4.8 M Cu2+ per sample) in the aqueous phase at the soil surface. This functional monitoring appears useful to quantify the potential environmental effects of the diverse, complex, and evolving SOM. Copyright © 2005 by Lippincott Williams & Wilkins, Inc. 1778 Changes in clay-associated organic matter quality in a C depletion sequence as measured by differential thermal analyses Plante A.F., Pernes M. and Chenu C. Geoderma 2005 129/3-4 (186-199) Land use changes result in significant decreases in soil organic matter stocks due to enhanced mineralization attributed to increased tillage, and due to decreased organic matter inputs. The current paradigm of soil organic matter dynamics suggests that decreasing organic matter stocks are also associated with shifts in organic matter quality to more resistant fractions as the more labile pools are decomposed. The objectives of the current study were to characterize changes in clay-associated organic matter quality in a soil C depletion sequence in terms of thermal properties, and to thermally characterize peroxide-resistant organic matter. Clay-sized fractions were isolated from a sequence of soils ranging from native forest to long-term bare fallow, and analyzed using thermogravimetry (TG) and differential scanning calorimetry (DSC) before and after hydrogen peroxide treatment. Differential scanning calorimetry traces had exothermic maxima near 285 and 333°C, consistent with analyses of chemically extracted organic matter and humic substances reported in the literature. Peak fitting analyses showed that these maxima consisted of several hidden peaks, but their interpretation is problematic. The qualitative shifts in the thermal properties of clay-associated organic matter with differing land use observed in the DSC traces were quantified using cultivation and fallow treatment to forest ratios. Thermogravimetric mass loss ratios were greater in the thermally labile (180-310°C) exothermic region than in the more thermally resistant (310-450°C) exothermic region. Similarly, ratios of peak heights and areas for the fitted DSC peaks were higher for the 324°C peak, compared to peaks at 257 and 284°C. The higher ratios indicate that the more thermally resistant organic matter has been retained and the more thermally labile organic matter is lost. The observed shift in the distribution of organic matter from thermally labile to thermally resistant fractions from forest to long-term bare fallow clay samples is consistent with the current paradigm of decomposition consisting of a shift to more biologically resistant fractions with increasing time under cultivation and decreasing organic matter inputs. These results suggest that the thermal properties of clay-associated organic matter are related to their biological decomposability. Hydrogen peroxide treatment of clay samples removed approximately 87% of the initial organic C in all samples, and peroxide-resistant organic matter was found to be more thermally stable than the whole. However, thermal analyses of the peroxide-resistant fraction did not show any changes in thermal properties with decreases in total C content. Rather than isolating a biologically resistant pool of organic matter, peroxide-resistant organic matter may isolate an inert pool of soil organic matter with thermal properties consistent with the presence of black carbon, which remains unchanged by changes in land use. © 2005 Elsevier B.V. All rights reserved. 1779 Ecosystem model spin-up: Estimating steady state conditions in a coupled terrestrial carbon and nitrogen cycle model Thornton P.E. and Rosenbloom N.A. Ecological Modelling 2005 189/1-2 (25-48) We tested a variety of methods for determining steady state solutions for Biome-BGC, a coupled model of terrestrial water, carbon, and nitrogen dynamics. Our objective was to identify 340 SOILS methods that could reduce the computational cost of model spinup relative to simulations running under the model’s native dynamics, while retaining or improving upon the simulation quality, where quality is judged by comparison to assumed values for the true steady state solution. Two classes of methods were tested: ad hoc methods that approximate steady state by taking advantage of specific characteristics of the modeled dynamics to produce individual time trajectories through the model state space, and general multivariate minimization methods that iteratively explore multiple time trajectories through state space in search of a reasonable steady state solution. We examined the behavior of these methods for both woody and herbaceous vegetation simulations. We found that both the ad hoc and the generalized methods, parameterized appropriately, could provide reductions in computational cost of 50-75% compared to the model’s native dynamics. With the exception of the generalized methods for the woody vegetation case, we also found that the quality of the simulated steady state solution was as good as or better than the native dynamics approach. The one method which performed consistently well across sites and vegetation types involved an acceleration of decomposition rates for the spin-up phase, resulting in 73 and 66% reductions in computational cost for woody and herbaceous vegetation types, respectively. © 2005 Elsevier B.V. All rights reserved. 1780 Carbon and decomposition model Yasso for forest soils Liski J., Palosuo T., Peltoniemi M. and Siev¨anen R. Ecological Modelling 2005 189/1-2 (168-182) Models are needed to estimate dynamics of carbon in forest soils, because changes in soil carbon are laborious to measure, and future levels of soil carbon can only be predicted using models. Current process-oriented soil carbon models are not suitable to all forestry-related applications. This is because they require specific input information that is not available for all forests, and their time step is shorter than a year which is typically used in forestry. We developed a dynamic soil carbon model Yasso to be used in forestry applications. Yasso simulates the stock of soil carbon, changes in this stock and the release of carbon from soil on an annual basis. It needs estimates of litter production, information on litter quality and basic data on climate to run. Yasso consists of five decomposition compartments and two woody litter compartments. Its parameter values were determined based on measurements of litter decomposition and soil carbon. The reliability of the output of Yasso was assessed by conducting an uncertainty analysis and comparing model-calculated estimates of soil carbon to measurements taken at different forest sites in southern Finland. According to the uncertainty analysis, the estimates for the amount of soil carbon are uncertain by nature, because they depend mostly on uncertain humus parameters. Still, when linked to a forest simulator to calculate litter production, Yasso gave similar estimates for the amount of soil carbon as were measured. The estimates for changes in soil carbon, on the other hand, are more reliable by nature because they depend on more accurately known parameters. These and other tests conducted so far suggest that Yasso is applicable to forests in a wide range of environments. Further tests will increase confidence in using it for different soils. © 2005 Elsevier B.V. All rights reserved. 1781 Litter decomposition affected by climate and litter quality - Testing the Yasso model with litterbag data from the Canadian intersite decomposition experiment Palosuo T., Liski J., Trofymow J.A. and Titus B.D. Ecological Modelling 2005 189/1-2 (183-198) Litterbag experiments provide valuable data for testing the accuracy of predictions of decomposition from soil carbon models. The soil carbon model Yasso describes litter decomposition based on basic climate and litter quality information, and was calibrated using European litterbag data. In this study, we tested the predictive capabilities of Yasso using independent litterbag data for 10 foliage litter types decomposed for 6 years at 18 upland forest sites across Canada (CIDET). The model underestimated mass of leaf litters remaining on CIDET sites, with only a small systematic error in predicting the effects of climate when effective temperature sum was used as the temperature variable in the model. The overall rate of decomposition was predicted correctly when mean annual temperature was used as the temperature variable, but then the model substantially overestimated climatic effects. The model correctly predicted differences in decomposition rates among litter types in the early years of decomposition, but underestimated them in later years. The decomposition rate of the litter type richest in phenolic compounds (larch needles) was systematically overestimated, and that of the litter type richest in O-alkyl compounds (grass leaves) was systematically underestimated. Accounting for these factors would improve the general applicability of the model. However, accounting for the initial nitrogen concentration of litter did not improve the accuracy of the model unless the initial lignin (i.e., acid unhydrolyzable residue) content was also taken into account. We conclude that the model Yasso accounts for most of the effects of climate and initial litter quality on the decomposition of a range of foliage litter types under varying climate conditions. Recalibration of the reference decomposition rates used in the model may improve the accuracy when applying the model outside of Europe. © 2005 Elsevier B.V. All rights reserved. 1782 Mathematical modelling of the composting process: A review Mason I.G. Waste Management 2006 26/1 (3-21) In this paper mathematical models of the composting process are examined and their performance evaluated. Mathematical models of the composting process have been derived from both energy and mass balance considerations, with solutions typically derived in time, and in some cases, spatially. Both lumped and distributed parameter models have been reported, with lumped parameter models presently predominating in the literature. Biological energy production functions within the models included first-order, Monod-type or empirical expressions, and these have predicted volatile solids degradation, oxygen consumption or carbon dioxide production, with heat generation derived using heat quotient factors. Rate coefficient correction functions for temperature, moisture, oxygen and/or free air space have been incorporated in a number of the first-order and Monod-type expressions. The most successful models in predicting temperature profiles were those which incorporated either empirical kinetic expressions for volatile solids degradation or CO2 production, or which utilised a first-order model for volatile solids degradation, with empirical corrections for temperature and moisture variations. Models incorporating Monod-type kinetic expressions were less successful. No models were able to predict maximum, average and peak temperatures to within criteria of 5, 2 and 2°C, respectively, or to predict the times to reach peak temperatures to within 8 h. Limitations included the modelling of forced aeration systems only and the generation of temperature validation data for relatively short time periods in relation to those used in fullscale composting practice. Moisture and solids profiles were well predicted by two models, but oxygen and carbon dioxide profiles were generally poorly modelled. Further research to obtain more extensive substrate degradation data, develop improved first-order biological heat production models, investigate mechanistically-based moisture correction factors, explore the role of moisture tension, investigate model performance over thermophilic composting time periods, provide more information on model sensitivity and incorporate natural ventilation aeration expressions into composting process models, is suggested. © 2005 Elsevier Ltd. All rights reserved. 1783 The determination of biological stability of composts using the Dynamic Respiration Index: The results of experience after two years Adani F., Ubbiali C. and Generini P. Waste Management 2006 26/1 (41-48) Biological stability was ascertained by using the Dynamic Respiration Index (DRI) on 144 samples of compost during the years 2003 and 2004, as a routine service for private subjects. Data obtained were collected and are critically discussed in this paper by using other parameters registered during tests, i.e., biomass temperature (T), specific airflow rate (Qs ) and biomass analytical data (pH). Good linear correlations were obtained for DRI vs. T, DRI vs. Qs and DRI vs. pH, confirming expected results based on the theoretical discussion. Consequently, using the analytical method proposed in this paper means both T and Q can be used as additional parameters for measurement of the biological SOILS stability of compost. As a result, T values of 25.8 and 30.5°C, and specific airflow rate of 8.6 and 13.4 m3 Mg-1 VS h-1 were found corresponding to 500 and 1000 mg O2 kgVS-1 h-1 , which, respectively, indicate a high and a medium degree of biological stability. © 2005 Elsevier Ltd. All rights reserved. 1784 Carbon dioxide and ammonia emissions during composting of mixed paper, yard waste and food waste Komilis D.P. and Ham R.K. Waste Management 2006 26/1 (6270) The objective of the work was to provide a method to predict CO2 and NH3 yields during composting of the biodegradable fraction of municipal solid wastes (MSW). The compostable portion of MSW was simulated using three principal biodegradable components, namely mixed paper wastes, yard wastes and food wastes. Twelve laboratory runs were carried out at thermophilic temperatures based on the principles of mixture experimental and full factorial designs. Seeded mixed paper (MXP), seeded yard waste (YW) and seeded food waste (FW), each composted individually, produced 150, 220 and 370 g CO2 -C, and 2.0, 4.4 and 34 g NH3 -N per dry kg of initial substrate, respectively. Several experimental runs were also carried out with different mixtures of these three substrates. The effect of seeding was insignificant during composting of food wastes and yard wastes, while seeding was necessary for composting of mixed paper. Polynomial equations were developed to predict CO2 and NH3 (in amounts of mass per dry kg of MSW) from mixtures of MSW. No interactions among components were found to be significant when predicting CO2 yields, while the interaction of food wastes and mixed paper was found to be significant when predicting NH3 yields. © 2005 Elsevier Ltd. All rights reserved. 1785 Soil mineral-organic matter-microbe interactions: Impacts on biogeochemical processes and biodiversity in soils Huang P.- M., Wang M.- K. and Chiu C.- Y. Pedobiologia 2005 49/6 (609-635) Soils are the central organizer of the terrestrial ecosystem. Their colloidal and particulate constituents, be they minerals, organic matter, and microorganisms, are not separate entities; rather, they are constantly interacting with each other. Interactions of these components control biogeochemical reactions, namely, the formation of short-range-ordered metal oxides, catalysis of humic substance formation, enzymatic stability and activity, mineral transformation, aggregate turnover, biogeochemical cycling of C, N, P, and S, and the fate and transformation of organic and inorganic pollutants. Furthermore, the impacts of mineral-organic matter-microorganism interactions and associated biogeochemical reactions and processes on biodiversity, species composition, and sustainability of the terrestrial ecosystem deserve close attention for years to come. This paper integrates the frontiers of knowledge on this subject matter, which is essential to uncovering the dynamics and mechanisms of terrestrial ecosystem processes and to developing innovative management strategies to sustain ecosystem health on the global scale. © 2005 Elsevier GmbH. All rights reserved. 1786 Effects of soil temperature and humidity on soil respiration rate under Pinus sylvestriformis forest (Chinese) Liu Y., Han S., Hu Y. and Dai G. Chinese Journal of Applied Ecology 2005 16/9 (1581-1585) Employing root-wrenching method and LI-6400-09 soil respiration chamber, this paper measured the diurnal changes of soil respiration rate with and without roots in situ on June 17, August 5, and October 10, 2003. The seasonal changes of soil respiration were also measured from May to September, 2004. The results showed that both the total and the root-wrenched soil respiration appeared single diurnal pattern, with the peaks presented during 12:00-14:00. The diurnal fluctuation of soil respiration on August 5 was smaller than that on June 17 and October 10. There were also obvious seasonal changes in total and root-wrenched soil respiration, as well as in root respiration, which were higher from June to August but lower in May and September. The average total soil respiration, root-wrenched soil respiration, and root respiration were 3.12, 1.94 and 1.18 mol CO2 m-2 s-1 , respectively, and the contribution of roots to total soil respiration ranged from 26.5% to 52.6% from May to September, 2004. There were exponential correlations between 341 respiration rate and soil temperature, and linear correlations between respiration rate and soil humidity. The Q10 values were 2.44, 2.55 and 2.27 for total soil respiration, root-wrenched soil respiration, and root respiration, respectively. The effect of soil temperature on root-wrenched soil respiration was lager than that on total soil respiration and root respiration. Soil humidity had a larger effect on total soil respiration than on root respiration and root-wrenched soil respiration. 1787 Temporal variation of soil respiration on sloping pasture of Heihe River basin and effects of temperature and soil moisture on it (Chinese) Chang Z., Shi Z., Feng Q. and Su Y. Chinese Journal of Applied Ecology 2005 16/9 (1603-1606) Employing LiCor 6400 gas exchange analyzer and soil respiration chamber attachment (LiCor Inc., Lincoln, NE, USA), this paper continuously measured the soil surface CO2 effluxes on the sloping pasture of Heihe River basin from early April to late October 2003 to investigate the soil CO2 efflux rate and its feedback to the changes of climate and land use. The results showed that from May to October, the diurnal variation of soil respiration was low at night, the lowest at 7:00, 6:30, 5:30, 6:00 and 7:00, raised rapidly at 7:00-8:30, and then descended at 16:00-18:30. The maximum soil CO2 efflux appeared at 15:00, 14:30, 14:30, 13:30, 14:00 and 15:00. The mean daily soil respiration rate was 0.31-6.98 molm-2 s-1 , with the maximum in July and August, the second in May and September, and nearly consistent in April and October. Soil respiration rate had an exponential and power correlation with temperature and soil moisture, respectively. 1788 Affecting factors of soil microorganism and root respiration (Chinese) Jia B., Zhou G., Wang F. and Wang Y. Chinese Journal of Applied Ecology 2005 16/8 (1547-1552) Soil respiration is an important part of the carbon cycle in terrestrial ecosystems, and its contribution to the global carbon budget has been the focus of wide concern. Researches on the affecting factors of soil microorganism and root respiration, the main components of soil respiration, contribute to the understanding of the role of soil respiration on global carbon cycle, and to the accurate evaluation of global carbon budget. This paper reviewed the direct and indirect affecting factors of soil microorganism and root respiration, including climate factors, soil properties, vegetation and litterfall, air CO2 concentration, and human activities. These affecting factors were interactive, and their contributions to soil microorganism and root respiration varied in temporal and spatial scales. The study on natural and anthropogenic factors of soil microorganism and root respiration was emphasized, and some related research tasks in the future were also proposed. Biota 1789 Effects of three soil tillage systems on some biological activities in an Ultisol from southern Chile Alvear M., Rosas A., Rouanet J.L. and Borie F. Soil and Tillage Research 2005 82/2 (195-202) Intensive tillage for annual crop production may be affecting soil health and quality. However, tillage intensity effects on biological activities of volcanic-derived soils have not been systematically investigated. We evaluated the effects of three different tillage practices on some biological activities of an Ultisol from southern Chile during the third year of a wheat-lupin-wheat crop sequence. Treatments were: no tillage with stubble burning (NTB), no tillage without stubble burning (NT) and conventional tillage with disk-harrowing and stubble burning (CT). Biological activities were evaluated in winter and summer at 0-200 mm and at three soil depths (0-50, 50-100 and 100-200 mm) in winter. Total organic C and N were significantly higher under no-tillage systems than CT. In general, NT increased C and N of microbial biomass in comparison with CT, especially in winter. Microbial biomass C was closely associated with microbial biomass N (r = 0.986, P < 0.05); acid phosphomonoesterase (r = 0.999, P < 0.05); -glucosidase (r = 0.978, P < 0.05), and others. Changes in biological activities occurred mainly in the upper soil layer 342 SOILS (0-50 mm depth) in spite of the short duration of the experiment. Biological activities could be used as practical biological indicators to apply the more appropriate management systems for increasing soil sustainability or productivity. © 2004 Elsevier B.V. All rights reserved. 1790 Bacterial, azotobacter, actinomycetes, and fungal population in soil after diazinon, imidacloprid, and lindane treatments in groundnut (Arachis hypogaea L.) fields Singh J. and Singh D.K. Journal of Environmental Science and Health - Part B Pesticides, Food Contaminants, and Agricultural Wastes 2005 40/5 (785-800) Bacterial, azotobacter, actinomycetes, and fungal populations were determined in groundnut (Arachis hypogaea L.) fields between July and November for three consecutive years (19971999) after insecticide treatments. Diazinon was applied for both seed and soil treatments. However, imidacloprid and lindane were used for seed treatments. An average half-life (t1/2 ) of diazinon in seed- and soil-treated fields was found to be 29.32 and 34.87 days, respectively. Its residues were found for 60 days in both cases. In diazinon seed treatment, an increase in azotobacter, fungi, and actinomycetes populations was observed in samples from the 15th and 30th days, and this trend continued until crop harvest. However, the bacterial population had not been affected by this treatment. The diazinon soil treatment had indicated some significant adverse effects on fungi and actinomycetes population, which recovered after 30 days. The population of bacteria and azotobacter increased significantly in this treatment. The residues of imidacloprid and lindane were found for 90 and 120 days with an average half-life of 40.9 and 53.3 days, respectively. Imidacloprid had no significant effect on fungi and actinomycetes populations up to 15 days, and between 15 to 60 days some adverse effects were indicated. However, some significant increases in bacterial and azotobacter population were observed. Lindane had no effect on bacterial and fungal population. However, its adverse effects were observed in actinomycetes and azotobacter populations between 30 to 60 days. Copyright © Taylor & Francis Inc. 1791 Does the positive feedback effect of nematodes on the biomass and activity of their bacteria prey vary with nematode species and population size? Fu S., Ferris H., Brown D. and Plant R. Soil Biology and Biochemistry 2005 37/11 (1979-1987) Two nematode species (Cruznema tripartitum and Acrobeloides bodenheimeri) were selected to test the hypotheses that bacterialfeeding nematodes affect bacterial biomass and activity and that this feedback effect varies with nematode species and population size. For each species, nematodes of three initial population sizes were inoculated onto bacterial colonies in separate microcosms. Nematode population, bacterial biomass and CO2 production were monitored in parallel microcosm settings. The responses of bacterial biomass to nematode species were different. Bacterial biomass increased significantly on d 8 in the presence of Acrobeloides when its initial numbers were 20 and 100 per microcosm; and bacterial biomass increased significantly on d 4 in the presence of Cruznema when its initial numbers were 5 and 20 per microcosm. Daily CO2 production of the microcosms with initial population sizes of 5, 20 and 100 Cruznema or of 5 and 100 Acrobeloides was significantly greater than that in microcosms without nematodes. However, the CO2 production of the microcosms with initial population of 20 Acrobeloides was not significantly different from that of the microcosms without nematodes. The increase in daily CO2 production per microcosm by Cruznema was generally greater than that by Acrobeloides for the first few days of the experiment. Nevertheless, the increase in daily CO2 production by an individual nematode was similar for both species and was a decreasing function of the initial nematode numbers. The feedback effect of each nematode species on its bacterial prey was estimated by fitting both bacterial biomass and CO2 production data to a model. Model outputs demonstrated that the feedback effect of Cruznema on bacteria was greater than that of Acrobeloides during the course of the experiment and the feedback effect of each species was not linearly correlated to initial nematode population sizes. Cruznema increased bacterial biomass and activity by a factor of 3.75-4.55 over the first 4 d, while Acrobeloides increased it by a factor between 1.97 and 3.40. 1792 Physiological and molecular characterisation of microbial communities associated with different water-stable aggregate size classes V¨ais¨anen R.K., Roberts M.S., Garland J.L. et al. Soil Biology and Biochemistry 2005 37/11 (2007-2016) We determined if the structure and function of microbial communities associated with different aggregate size classes was influenced when the aggregate formation occurred under either nitrogen (N) limitation (straw only incubation treatment) or carbon (C) limitation (straw+N incubation treatment). Using a combination of community-level physiological (BD Oxygen Biosensor assay) and molecular (terminal restriction fragment length polymorphism; T-RFLP) profiling methods, we found differences in both microbial community composition and the physiological response of these communities between different aggregate size classes. The response of fungal and bacterial communities to ‘straw only’ and ‘straw+N’ treatments differed in that bacterial community composition was affected by the treatments, whereas fungal community composition was not. The magnitude of change in the bacterial community response increased with decreasing aggregate size. However, there were no significant differences in the mean bacterial community richness (number of different terminal restriction fragments; TRFs) between different aggregate size classes for the two treatments. In general, microbial communities associated with larger aggregate size fractions (large and small macroaggregates) were found to have a significantly faster respiratory response than the communities associated with microaggregates. Application of the fungal inhibitor cycloheximide resulted in a significant reduction in the utilization of cellulose, chitin, mannose, xylan, and xylose by the microbial communities associated with all aggregate size classes, indicating that fungi are significant contributors to the utilization of these compounds. Our results demonstrate that the BD Oxygen Biosensor assay offers a valuable new tool for community level physiological profiling. When used in combination with census-based methods such as T-RFLP, a greater level of resolution can be achieved. © 2005 Elsevier Ltd. All rights reserved. 1793 Relationship between plants and soil microbial communities in fertilized grasslands Benizri E. and Amiaud B. Soil Biology and Biochemistry 2005 37/11 (2055-2064) The relationship between biodiversity and ecosystem functioning is of major scientific concern today. Few studies though have measured the interactions between soil microorganisms and plant diversity, the purpose of this study was to examine the link between plant diversity and microbial communities in fertilized versus unfertilized grasslands. Experiments were carried out on a permanent grassland in north-eastern France where agricultural practices had remained unchanged for the last 13 years. The experimental design included two plots of 300 m2 (fertilized at 120 kg N ha-1 or non-fertilized). Plots were replicated into three equal sub-plots (100 m 2 ). From each sub-plot, six samples of soil and vegetation were taken at three dates during floristic development. At sampling, ground cover of each species was estimated, and total amount of C and N was determined in aboveground and root biomass. Soil samples were analyzed in order to measure the metabolic fingerprints of microorganisms using Biolog® GN2 microplates. Floristic composition and carbon substrate utilization patterns of rhizobacterial communities were more diversified in unfertilized than fertilized plots. In unfertilized plots, the development of Convolvulus arvensis and two legumes (Trifolium pratense and Trifolium repens) may help maintain observed floristic diversity. Moreover, an inversion of C and N distribution between aboveground and root biomass during the vegetation cycle probably induced a variation of rhizodeposition. This phenomenon could explain the differences of rhizobacterial metabolic fingerprints observed between experimental plots. © 2005 Elsevier Ltd. All rights reserved. SOILS 1794 Soil feedback effects to the foredune grass Ammophila arenaria by endoparasitic root-feeding nematodes and whole soil communities Brinkman E.P., Troelstra S.R. and Van Der Putten W.H. Soil Biology and Biochemistry 2005 37/11 (2077-2087) In coastal foredunes, the grass Ammophila arenaria develops a soil community that contributes to die-back and replacement by later successional plant species. Root-feeding nematodes and pathogenic soil microorganisms are involved in this negative feedback. Regular burial by wind-blown beach sand results in vigorous growth of A. arenaria, probably because of enabling a temporary escape from negative soil feedback. Here, we examine the role of root-feeding nematodes as compared to the whole soil community in causing negative feedback to A. arenaria. We performed a 3-year sand burial experiment in the field and every year we determined the feedback of different soil communities to plant growth in growth chamber bioassays. In the field, we established A. arenaria in tubes with beach sand, added three endoparasitic root-feeding nematode species (Meloidogyne maritima, Heterodera arenaria and Pratylenchus penetrans) or root zone soil to the plants, and created series of ceased and continued sand burial. During three subsequent years, plant biomass was measured and numbers of nematodes were counted. Every year, bioassays were performed with the field soils and biomass of seed-grown A. arenaria plants was measured to determine the strength of feedback of the established soil communities to the plant. In the field, addition of root zone soil had a negative effect on biomass of buried plants. In the bioassays, addition of root zone soil also reduced the biomass of newly planted seedlings, however, only in the case when the field plants had not been buried with beach sand. Addition of the three endoparasitic root-feeding nematodes did not influence plant biomass in the field and in the bioassays. Our results strongly suggest that the negative feedback to A. arenaria is not due to the combination of the three endoparasitic nematodes, but to other components in the soil community, or their interactions with the nematodes. © 2005 Elsevier Ltd. All rights reserved. 1795 Microbial carbon dynamics in nitrogen amended Arctic tundra soil: Measurement and model testing Stapleton L.M., Crout N.M.J., S¨awstr¨om C. et al. Soil Biology and Biochemistry 2005 37/11 (2088-2098) We examined the responses of grazers (protozoa and nematodes) and their main food sources to low levels of nitrogen (N) fertilisation and applied carbon (C) flux models to our data. Replicate plots of tundra soil adjacent to the Kongsfjorden (Svalbard 78°N) were amended with ammonium and nitrate at concentrations of 1 and 5 kg N ha-1 to assess the impact of anthropogenic N deposition over three summers. Bacterial abundance as determined using the fluorochrome SYBR Green and epifluorescence microscopy ranged between 9.73108 and 102.49108 cells/g dry wt of soil, with a significant response to N addition occurring only during the second sampling in 2001. Despite little change in bacterial biomass, bacterial production (measured by the incorporation of 3 H thymidine into DNA) during the second sampling in 2002, increased in NH4 enriched plots compared to control and NO3 amended plots, indicating that NH 4 was the preferred source of inorganic N. The main bacterial predators were heterotrophic flagellates (HNAN) and naked amoebae, which showed no significant response to the N addition. HNAN showed a correlation with bacterial abundance suggesting a dependence on bacteria as a food source. The inability of a microbial C flux model to fit our data (RWSS/data=18.6, r 2 =0.088) was at least partly due to insufficient bacterial production to meet the C demands of predator taxa, and high variability in the data over time. This is reflected in the performance statistics for model variants where select microbial taxa and data were removed. The optimal model in terms of predictive utility was a model with data from 2002 only, minus naked amoebae (RWSS/data=2.45, r2 =0.806). © 2005 Elsevier Ltd. All rights reserved. 1796 Responses of oribatid mite communities to summer drought: The influence of litter type and quality Taylor A.R. and Wolters V. Soil Biology and Biochemistry 2005 37/11 (2117-2130) A litterbag experiment was used to study the impact of extended periods of summer drought on the structure of oribatid mite com- 343 munities (Acari, Oribatida) developing in two litter types (beech, spruce) of two qualities (fresh, pre-incubated). Within each litter type, litter quality determined species composition and densities and, in turn, this determined the impact of drought upon the oribatid mite communities. In both litter types, drought had a greater impact on community development in the pre-incubated compared to the fresh litter. In the short-term perspective of the present study, oribatid mite communities in beech litter were less sensitive to summer drought than those in spruce litter. This was partly due to the presence of site-specific, drought-tolerant species but seemed also strongly related to differences in the decomposition patterns between the litter types. Marked changes in densities and composition of oribatid communities after only one period of summer-drought suggest that there is a potential for a significant alteration of oribatid community structure in both litter types if climatic changes persist. © 2005 Elsevier Ltd. All rights reserved. 1797 Earthworm ecological groupings based on 14 C analysis Briones M.J.I., Garnett M.H. and Piearce T.G. Soil Biology and Biochemistry 2005 37/11 (2145-2149) We report the first use of 14 C isotope analysis to investigate the ecological grouping of earthworms. Mature endogeic (Allolobophora caliginosa), mature epigeic (Lumbricus rubellus), and semimature anecic worms (A. longa) were collected in September 2002 from a woodland site at Lancaster, UK. Because anecic worms are known to have a variable feeding behaviour and can show dietary changes during ontogeny, additional immature and mature specimens of A. longa were also collected from the same site in January 2004. Epigeic earthworms showed the lowest radiocarbon concentration (0-3-years old), implying that they assimilated more recently fixed carbon than the anecic or endogeic earthworms. The age of carbon assimilated in mature anecic species (5-7-years old) was closer to that of endogeic species (58-years old) than to epigeics, suggesting that a greater proportion of older, more mineralised organic matter may form part of the diet of the anecic earthworms than previously thought. These results suggest that 14 C approaches are useful in the study of the feeding behaviour of detritivorous animals by providing in situ information on the age of the carbon assimilated by the worms. This can then be related to their role in ecosystem functioning, particularly in carbon cycling. © 2005 Elsevier Ltd. All rights reserved. 1798 Diversity of rhizobia isolated from an agricultural soil in Argentina based on carbon utilization and effects of herbicides on growth Zabaloy M.C. and G´omez M.A. Biology and Fertility of Soils 2005 42/2 (83-88) Seventy-six rhizobial isolates belonging to four different genera were obtained from the root nodules of several legumes (Vicia sativa, Vicia faba, Medicago sativa, Melilotus sp., Glycine max and Lotus corniculatus). The action of five commonly used herbicides [2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate (GF), dicamba, atrazine and metsulfuron-methyl] on the growth of rhizobial strains was assessed. Subsequently, GF and 2,4D were tested in a minimum broth as C and energy sources for 20 tolerant strains. The ability of these strains to metabolize different carbon sources was studied in order to detect further differences among them. Tolerance of the bacteria to agrochemicals varied; 2,4-D and GF in solid medium inhibited and diminished growth, respectively, in slow-growing rhizobial strains. Among slow-growing strains we detected Bradyrhizobium sp. SJ140 that grew well in broth + GF as the sole C and energy source. No strain was found which could use 2,4-D as sole C source. The 20 strains studied exhibited different patterns of C sources utilization. Cluster analysis revealed three groups, corresponding to four genera of rhizobia: Rhizobium (group I), Sinorhizobium (group II) and Mesorhizobium-Bradyrhizobium (group III). On the basis of the results obtained on responses to herbicides and C sources utilization by the isolates investigated, it was possible to differentiate them at the level of strains. These results evidenced a considerable diversity in rhizobial populations that had not been previously described for Argentinean soils, and suggested a physiological potential to use natural and xenobiotic C sources. 344 SOILS 1799 Soil microbial biomass and activities in a Japanese Andisol as affected by controlled release and application depth of urea Chu H.Y., Hosen Y., Yagi K. et al. Biology and Fertility of Soils 2005 42/2 (89-96) This experiment was conducted in maize field plots to study the effects of controlled release and application depth of urea on soil microbial biomass and activities at two depths of surface soil of a Japanese Andisol from June to September, 2001. Three N amendment treatments and a Control were included in this experiment: deep application (8 cm) of controlled release urea; deep application (8 cm) of conventional urea; surface application of conventional urea; Control, without N application. Prior to this experiment, the field plots received the same N fertilizer treatments for two consecutive years under maize/barley rotation. Soil microbial biomass, dehydrogenase and nitrification activities exhibited great vertical and temporal variations during the maize growth season, and the microbial biomass was significantly correlated to soil water-filled pore space (p<0.01). N fertilization did not significantly affect the microbial biomass, but greatly increased the dehydrogenase and nitrification activities. The increase in the microbial activities following N fertilization was not attributed to the increase in microbial biomass but to the increase in intrinsic microbial activities. Controlled release urea was found to continuously affect the dehydrogenase activity over a shorter distance, while conventional urea could greatly increase the enzyme activity for a shorter period of time. Both controlled release and deep application of urea had potentials to reduce the nitrification activity and suggested that the nitrate production might be decreased in 0-10 cm surface soil. Deep application of urea increased aboveground N uptake by maize and then the recovery rate of N fertilizer, whereas controlled release of urea greatly increased grain yield and N uptake by grain. 1800 Spatial variation of soil enzyme activities and microbial functional diversity in temperate alley cropping systems Mungai N.W., Motavalli P.P., Kremer R.J. and Nelson K.A. Biology and Fertility of Soils 2005 42/2 (129-136) Spatially dependent patterns in microbial properties may exist in temperate alley cropping systems due to differences in litter quality and microclimate in areas under trees compared to those in the alleys. The effect of tree row location was evaluated for its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at the tree row and at the middle of the alley at two sites: a 21-year-old pecan (Carya illinoinensis)/bluegrass (Poa trivials) intercrop (Pecan site) and a 12-year-old silver maple (Acer saccharinum)/soybean (Glycine max)-maize (Zea mays) rotation (Maple site). Sampling was done in fall 2001 and summer 2002. -Glucosidase activities, Biolog patterns expressed as average well color (AWC), substrate richness, and Shannon diversity index, and total Kjeldahl nitrogen (TKN) were significantly higher (P<0.05) in the tree row than at the middle of the alley for surface soils at the Pecan site. Fluorescein diacetate (FDA) hydrolytic activity was also higher at the tree row for soils sampled in the fall, but did not differ significantly for soils sampled in the summer. At the Maple site, AWC and substrate richness were significantly higher at the tree row for soils sampled in 2001. Soil volumetric water content and temperature were generally lower in the tree row at the Maple site. The results of this study suggest that functionally different microbial populations may be present under pecan trees compared to cropped alleys which may promote disparities in nutrient availability necessitating differential long-term nutrient management in such alley cropping systems. 1801 Population and behavioural level responses of arable soil earthworms to boardmill sludge application Butt K.R., Nieminen M.A., Sir´en T. et al. Biology and Fertility of Soils 2005 42/2 (163-167) The response of earthworms to soil application of boardmill waste sludge was quantified in field and laboratory experiments. The influence of one application of 6104 tonnes ha-1 of unamended sludge was tested against no application on silty-clay arable soil. After 2 years, results in stubble-cultivated soil showed a 1.7 times lower density of earthworms where sludge was added, whereas there was no difference in average earthworm fresh weight. In direct-drilled soil, there was an indication of lower average num- bers of Lumbricus terrestris middens when sludge was applied. Negative impacts in the field may have been due to indirect negative effects of the sludge application. In the laboratory, habitat choice tests were undertaken with two common species from the field site using sludge-based mulch and fertiliser products. Aporrectodea caliginosa showed no discernible preference between soil and soil mixed with unamended sludge (mulch), but favoured soil over soil mixed with sludge and chicken manure (fertiliser). Tests with L. terrestris showed a similar pattern. The preference of L. terrestris for the two products was compared with that for chopped barley straw by direct observation of foraging behaviour. Differences in foraging time of L. terrestris for different feeds were not significant, but mass of straw collected was significantly greater compared with either type of sludge treatment. 1802 Soil microbial indices as bioindicators of environmental changes in a poplar plantation Moscatelli M.C., Lagomarsino A., Marinari S. et al. Ecological Indicators 2005 5/3 (171-179) An understanding of microbial biomass and microbial activity as part of belowground processes as affected by elevated CO2 is crucial in order to predict the long-term response of ecosystems to climatic changes. The ratio of biomass C to soil organic C (Cmic:Corg), the metabolic quotient (the specific soil respiration of the microbial biomass, qCO2 ), the C mineralization quotient (the fraction of total organic C mineralized throughout the incubation, qM), the microbial biomass change rate quotient (qC) and soil inorganic nitrogen content were determined on soil samples taken during 3 years (Fall 2000-Fall 2003) in a poplar plantation exposed to increased atmospheric CO2 by means of FACE (Free Air CO2 Enrichment) technique and nitrogen fertilization. A competition for nitrogen between plants and microrganisms, stronger in FACE plots, induced a stress condition within microbial community. FACE treatment provided C for microbial growth (Cmic:Corg), but reducing nitrogen availability, led to a higher microbial loss over time (qC). Nitrogen fertilization decreased microbial mortality lowering energetic maintenance requirements (qCO2 ) and induced a short-term shift in favour of microrganisms more rapid in the use of the resources. The C mineralization quotient (qM) was not affected by either FACE nor fertilization treatment meaning that the fraction of total organic carbon mineralized during the incubation period did not vary significantly. © 2005 Elsevier Ltd. All rights reserved. 1803 Distribution and diversity of soil protozoa in the McMurdo Dry Valleys of Antarctica Bamforth S.S., Wall D.H. and Virginia R.A. Polar Biology 2005 28/10 (756-762) The polar desert soils of the McMurdo Dry Valley region support a limited water film community dominated by flagellates, amoebae, and nematodes. This study describes the protozoa and compares their distribution to nematodes. In 50 samples collected from 12 locations, rotifers and tardigrades were infrequent, and ciliates and testacea were rare. Soil protozoa occurred at all sites but the dominant nematode, Scottnema lindsayae (Timm 1971), did not, indicating soil habitat factors limiting nematode distribution are not limiting to protozoa. In contrast to the nematode species, which are all endemic to Antarctica, there were no endemic protozoan morphospecies found in our samples. The protozoan abundance was several orders of magnitude greater than that of the nematodes, and the species diversity was much greater. Most of the protozoa grew better at lower incubation temperatures. The ubiquitous distribution of protozoa suggests their importance in soil food webs and nutrient cycling in the dry valleys. © Springer-Verlag 2005. 1804 Invertebrate diversity under artificial cover in relation to boreal forest habitat characteristics Ferguson S.H. and Berube D.K.A. Canadian Field-Naturalist 2004 118/3 (386-394) We investigated invertebrate diversity in boreal forests using an experimental design that consisted of counting soil invertebrates under artificial cover. The aim was to assess the utility of using soil invertebrate diversity as a measure of ecosystem health. The study area was grouped into five habitats: upland hardwood, low- SOILS land hardwood, conifer, shrub, and conifer-grass. Simpson’s and Shannon’s indices of invertebrate diversity were negatively correlated with percent herbaceous cover. Number of recognizable taxonomic units (RTU richness) was negatively correlated with percent litter cover. The number of individual invertebrates was positively correlated with soil moisture and negatively correlated with percent conifer cover. Invertebrate diversity varied among habitat types, with conifer forests (spruce, fir, pine) having the highest diversity and regenerating conifer-grass forests having the lowest diversity, suggesting that successional stages affect diversity. The most productive sites, upland and lowland hardwood habitats, had the highest abundance of soil invertebrates, although intermediate diversity compared to the other five habitats. The results are consistent with the view that diversity increases and then decreases with productivity and disturbance over succession (ca. 50-100 yr). Hence, maintenance of soil invertebrate diversity in managed boreal forests requires the provision of a varied landscape with a mosaic of disturbance regimes. 1805 Linking species richness, biodiversity and ecosystem function in soil systems Coleman D.C. and Whitman W.B. Pedobiologia 2005 49/6 (479497) Soils are the central organizing entities in terrestrial ecosystems and possess extremely diverse prokaryotic and eukaryotic biota. They are physically and chemically complex, with micro- and macro-aggregates embedded within a solid, liquid and gaseous matrix that is continually changing in response to natural and human-induced perturbations. Recent advances in molecular techniques in systematics have provided opportunities for the study of biodiversity and biocomplexity of soil biota. A symposium and workshop on soil biogeochemistry and biodiversity International Symposium on Impacts of Soil Biodiversity on Biogeochemical Processes in Ecosystems, Taiwan Forestry Research Institute, Taipei, Taiwan April 18-24, 2004. Convened an international array of participants working in biomes on virtually every continent on the planet (ranging from polar to tropical regions). This special issue reports on the theoretical bases and applications of molecular methods for the measurement of soil biodiversity. Themes addressed include a melding of classical taxonomic investigations with biochemical fingerprinting and molecular probing of organism identities. Several papers highlight new advances in identifications of prokaryotic and eukaryotic organisms. Examples include new developments in "fingerprinting" of microbes active in "mycorrhizospheres" using immunocapture and other innovative techniques. Developments in the study of impacts of invasive plant and animal species on ecosystem function and subsequent microbial community composition and function have been very great in the last 2-3 years. Soils are major repositories of legacies, including fine and coarse woody debris and other organic products, which have feedbacks on soil diversity. The ways in which species diversity and function of microbial and faunal communities interact and their importance to ecosystem function are examined in biological and biochemical detail. This paper provides an overview of soil biodiversity and its feedbacks on soil biogeochemical processes in ecosystems. © 2005 Elsevier GmbH. All rights reserved. 1806 Modeling trophic pathways, nutrient cycling, and dynamic stability in soils Moore J.C., McCann K. and De Ruiter P.C. Pedobiologia 2005 49/6 (499-510) Soil communities are compartmentalized into pathways of trophic interactions and nutrient flows that originate from plant roots, bacteria and fungi. The pathways differ in terms of the organisms that comprise them, the habitats that the organisms occupy and the rates by which the organisms process and transfer material and energy. The fungi, nematodes and arthropods within the fungal pathway live in air-filled pore spaces and water films, while the bacteria, protozoa, and nematodes within the bacterial pathway occupy water-filled pore spaces and water films. Organisms within the fungal pathway have longer generation times and process matter at slower rates than those within the bacterial pathway. Empirical studies have shown that under natural conditions the pathways co-exist in a stable manner. The relative sizes (indexed by the densities of organisms) and activities (indexed by nutrient-flow rates, excretion rates and respiration rates) of 345 the pathways may change seasonally and in response to minor disturbances, but they persist. However, large anthropogenic and natural disturbances induce shifts in the relative sizes and activities of the pathways. Coincident with these shifts are reports of changes in the aboveground plant community and the availability and retention of plant limiting nutrients. We developed simple models of the bacterial and fungal pathways to explore the consequences of the observed shifts on the dynamic stability of the system. The more stable configurations occurred when there was a balance in the flow of nutrients between the two pathways. Large shifts in nutrient cycling and community structure towards either the fungal pathway or toward the bacterial pathway resulted in less stable or unstable configurations. © 2005 Elsevier GmbH. All rights reserved. 1807 Oribatid mite community structure and tree species diversity: A link? Kaneko N., Sugawara Y., Miyamoto T. et al. Pedobiologia 2005 49/6 (521-528) Differences in tree species may lead to contrasting soil environments via differences in litter chemical quality and physical environmental factors, such as soil type and soil moisture. However, separating the effects of litter quality and physical environment is difficult under field conditions. Both litter quality and soil environment affect the species composition of the soil animal community. A diversity gradient of canopy tree species (11-25 species) located on homogeneous soil substrate at Tomakomai Experimental Forest of Hokkaido University was used to analyse the relationship between tree species diversity and oribatid mite community structure. Soil samples were collected from three levels of tree species richness (high, intermediate and low) with three replicates each, in July 2000. Leaf area index (LAI) was positively correlated with tree species diversity suggesting higher litter input into the soils with increasing tree diversity. However, the tree species diversity gradient affected neither accumulation of litter on the forest floor nor abundance and species richness of oribatid mites. Canopy and understory plant species richness, LAI, total soil carbon and biomass of epigeic and endogeic earthworms did not significantly affect mite community structure as indicated by redundancy analysis (RDA). The results suggest that oribatid mite community structure is minimally affected by tree species diversity and associated changes in litter diversity. © 2005 Elsevier GmbH. All rights reserved. 1808 Soil communities and plant litter decomposition as influenced by forest debris: Variation across tropical riparian and upland sites Ruan H., Li Y. and Zou X. Pedobiologia 2005 49/6 (529-538) Forest debris on ground surface can interact with soil biota and consequently change ecosystem processes across heterogeneous landscape. We examined the interactions between forest debris and litter decomposition in riparian and upland sites within a tropical wet forest. Our experiment included control and debrisremoval treatments. Debris-removal reduced leaf litter decomposition rates in both the riparian and upland sites. Debris-removal also reduced soil microbial biomass C in the upland site, but had no effect on microbial biomass C in the riparian site. In contrast, debris-removal altered the density of selected arthropod groups in the riparian site. Litter decomposition rates correlated with both soil microbial biomass and the density of millipedes in a multiple stepwise regression model. Removal of forest debris can substantially reduce rates of leaf litter decomposition through suppressing soil activities. This influence can be further modified by landscape position. Forest debris plays an essential role in maintaining soil activities and ecosystem functioning in this tropical wet forest. © 2005 Elsevier GmbH. All rights reserved. 1809 Plant litter decomposition influenced by soil animals and disturbance in a subtropical rainforest of Taiwan Hou P.- C.L., Zou X., Huang C.- Y. and Chien H.- J. Pedobiologia 2005 49/6 (539-547) Soil fauna has been postulated as one of the paramount determinants of decomposition in the humid tropics. However, its effect on litter decomposition has only been demonstrated in few forest sites in Central America. In addition, landslide is a common disturbance associated with heavy rainfall brought by tropical 346 SOILS cyclones in the tropics and can potentially alter abundance and structure of soil animals and thus affect litter decomposition. In this study, we examined the effect of soil animals on litter decomposition in an Asian subtropical monsoon forest and compared the animal effects in landslide-disturbed (2 years old) and undisturbed sites. Animal exclusion by naphthalene treatment significantly reduced the density and diversity of litterbag animals and slowed down the rate of decomposition in both landslidedisturbed and undisturbed sites. However, density (per unit area) and diversity of the litter animals and litter decomposition rate did not differ between the landslide-disturbed and undisturbed sites for both control and animal-excluded treatments. Our data suggest that the abundance of soil animals is not limited by litter mass. Furthermore, soil fauna recover quickly from landslides, and fauna’s facilitative effect on litter decomposition is not altered after their recovery. © 2005 Elsevier GmbH. All rights reserved. 1810 Correlation between earthworms and plant litter decomposition in a tropical wet forest of Puerto Rico Dechaine J., Ruan H., Sanchez- De Leon Y. and Zou X. Pedobiologia 2005 49/6 (601-607) Earthworms are recognized to play an important role in the decomposition of organic materials. To test the use of earthworms as an indicator of plant litter decomposition, we examined the abundance and biomass of earthworms in relation to plant litter decomposition in a tropical wet forest of Puerto Rico. We collected earthworms at 0-0.1 m and 0.1-0.25 m soil depths from upland and riparian sites that represent the natural variation in soils and decomposition rates within the forest. Earthworms were hand-sorted and weighed for both fresh and dry biomass. Earthworms were dominated by the exotic endogeic species Pontoscolex corethrurus M¨uller; they were more abundant, and had higher biomasses in the upland than in riparian sites of the forest. Plant leaf litter decomposed faster in the upland than riparian sites. We found that earthworm abundance in the upper 0.1 m of the soil profile positively correlated with decomposition rate of plant leaf litter. Ground litter removal had no effect on the abundance or biomass of endogeic earthworms. Our data suggest that earthworms can be used to predict decomposition rates of plant litter in the tropical wet forest, and that the decomposition of aboveground plant litter has little influence on the abundance and biomass of endogeic earthworms. © 2005 Elsevier GmbH. All rights reserved. 1811 Seasonal dynamics of soil microbial biomass in coastal sand dune forest Chen T.- H., Chiu C.- Y. and Tian G. Pedobiologia 2005 49/6 (645-653) Sand dunes are a typical landscape in the coast of western Taiwan, where Casuarina forests were established decades ago to stabilize sand dunes and protect the inland vegetation. Study of microbial biomass in such an ecosystem may give insights into the role of microbes in soil fertility and nutrient cycling. We established our study sites in two topographic units based on elevation and drainage types: upland and lowland. The study lasted for 2 years, and soil samples were collected every 3 months. Microbial biomass C (C mic ) and N (Nmic ) were high in a shallow humic layer that rested on top of the soil (1222-1319 mg kg-1 for Cmic and 245-276 mg kg-1 for Nmic ) and declined sharply to only one-tenth of the above values in the underlying surface soil (0-10 cm depth). Microbial biomass Cmic and Nmic in humic and surface soil were not significantly different between upland and lowland sites. In the upland soils, the mean Cmic was highest in autumn for both the humic and surface soil, and lowest in spring and summer for the humic layer and summer for the surface soil layer. In the lowland soils, the Cmic was highest in winter for both humic and surface soil, and lowest in spring and autumn for the humic layer and spring and summer for surface soil. Strong fluctuations of Cmic and Nmic were associated with the soil moisture prior to sampling, which appeared to control the size of microbial biomass in this environment. Temperature had little effect on the dynamics of soil microbial biomass in the sand dune forest ecosystem. © 2005 Elsevier GmbH. All rights reserved. 1812 Glomus intraradices dominates arbuscular mycorrhizal communities in a heavy textured agricultural soil Mathimaran N., Ruh R., Vullioud P. et al. Mycorrhiza 2005 16/1 (61-66) Arbuscular mycorrhizal fungal (AMF) spore communities were surveyed in a long-term field fertilization experiment in Switzerland, where different amounts of phosphorus (P) were applied to soil. Plots receiving no P as well as plots systematically fertilized in excess to plant needs for 31 years were used to test the hypothesis that application of P fertilizer changes the composition and diversity of AMF communities. AMF spores were isolated from the field soil, identified, and counted so as to quantify the effect of P fertilization on AMF spore density, composition, and diversity. Trap cultures were established from field soil with four host plants (sunflower, leek, maize, and Crotalaria grahamiana), and the spore communities were then analyzed in substrate samples from the pots. Altogether, nine AMF species were detected in the soil. No evidence has been acquired for effect of P fertilization on spore density, composition, and diversity of AMF in both the field soil and in trap cultures. On the other hand, we observed strong effect of crop plant species on spore densities in the soil, the values being lowest under rapeseed and highest under Phacelia tanacetifolia covercrop. The identity of plant species in trap pots also significantly affected composition and diversity of associated AMF communities, probably due to preferential establishment of symbiosis between certain plant and AMF species. AMF spore communities under mycorrhizal host plants (wheat and Phacelia in the fields and four host plant species in trap pots) were dominated by a single AMF species, Glomus intraradices. This resulted in exceptionally low AMF spore diversity that seems to be linked to high clay content of the soil. © Springer-Verlag 2005. 1813 Oribatid mite (Acari, Oribatida) feeding on ectomycorrhizal fungi Schneider K., Renker C. and Maraun M. Mycorrhiza 2005 16/1 (67-72) The coexistence of a large number of soil animals without extensive niche differentiation is one of the great riddles in soil biology. The main aim of this study was to explore the importance of partitioning of food resources for the high diversity of micro-arthropods in soil. In addition, we investigated if ectomycorrhizal fungi are preferentially consumed compared to saprotrophic fungi. Until today, ectomycorrhizal fungi have never been tested as potential food resource for oribatid mites. We offered six ectomycorrhizal fungi [Amanita muscaria (L.) Hook., Boletus badius (Fr.) Fr., Cenococcum geophilum Fr., Laccaria laccata (Scop.) Fr., Paxillus involutus (Batsch) Fr. and Piloderma croceum J. Erikss. & Hjortstam], one ericoid mycorrhizal fungus [Hymenoscyphus ericae (D.J. Read) Korf & Kernan] and three saprotrophic fungi [Agrocybe gibberosa (Fr.) Fayod, Alternaria alternata (Fr.) Keissl. and Mortierella ramanniana (A. Møller) Linnem.] simultaneously to each of the mainly mycophagous oribatid mite species Carabodes femoralis (Nicolet), Nothrus silvestris Nicolet and Oribatula tibialis Nicolet. The ericoid mycorrhizal fungus H. ericae and the ectomycorrhizal fungus B. badius were preferentially consumed by each oribatid mite species. However, feeding preferences differed significantly between the three species, with O. tibialis being most selective. This study for the first time documented that oribatid mites feed on certain ectomycorrhizal fungi. © Springer-Verlag 2005. 1814 Effects of replacing natural secondary broad-leaved forest with Cunninghamia lanceolata plantation on soil biological activities (Chinese) Hu Y., Wang S., Yan S. and Gao H. Chinese Journal of Applied Ecology 2005 16/8 (1411-1416) This paper studied the effects of replacing natural secondary broad-leaved forest with Cunninghamia lanceolata plantation in the south, central and upstate areas of subtropical China on the changes of soil chemical and biological properties. The results showed that after replacing with Cunninghamia lanceolata plantation, the total organic carbon (TOC) content in surface soil decreased by 31.51% - 58.24%, and the contents of soil total N and P, pH value, C/N and C/P also decreased to different degree. Soil microbial amount was less than that under natural SOILS secondary broad-leaved forest, soil urease, invertase, catalase and dehydrogenase activities decreased, while soil polyphenol oxidase activity increased by 8% - 40%. The respiration rate of Cunninghamia lanceolata soil was 51.15% - 54.48% lower than that of natural secondary broad-leaved forest soil. The correlation between soil TOC and polyphenol oxidase activity was negative (R = -0.723, n = 18), while those between soil TOC, N, P and other enzyme activities were positive. It could be concluded that replacing natural secondary broad-leaved forest with Cunninghamia lanceolata plantation worsened soil quality, and the loss of soil organic matter in Cunninghamia lanceolata plantation ecosystem might be one of the important factors resulted in the decrease of soil nutrients and enzyme activities. 1815 Ecological distribution patterns of soil microbes under artificial Eucalyptus Grandis stand (Chinese) Feng J. and Zhang J. Chinese Journal of Applied Ecology 2005 16/8 (1422-1426) In order to find out the ecological distribution patterns of soil microbes under artificial Eucalyptus grandis stand, the amount and distribution of soil bacteria, fungi and actinomycetes in Hongya County of Sichuan Province were investigated in 2004. The results showed that soil microbial population under Eucalyptus grandis stand varied with seasons, being the maximum in autumn, fewer in spring, and the minimum in summer. The numbers were decreased in order of bacteria > actinomycetes > fungi, which were mainly concentrated in 0-20 cm soil layer, and rapidly decreased with increasing soil depth. In 0-60cm soil layer, the numbers of aerobic bacteria were 0. 31 106 -14.39 106 , actinomycetes were 0.06 106 -0.79 106 , fungi were 0.06 106 -0.79 106 , and anaerobes were 0.05 106 -3.22 106 CFUg-1. Comparing with artificial C. glauca stand and farming land, Eucalyptus grandis stand had a larger number of soil microbes, suggesting that Eucalyptus grandis, was benefit, for soil microbial activity. The Simpson and Shannon-Wiener index of the physiological groups of bacteria was 0.773 and 1.896, respectively. 1816 Main determinants of forest soil respiration along an elevation/temperature gradient in the Italian Alps Rodeghiero M. and Cescatti A. Global Change Biology 2005 11/7 (1024-1041) The main determinants of soil respiration were investigated in 11 forest types distributed along an altitudinal and thermal gradient in the southern Italian Alps (altitudinal range 1520 m, range in mean annual temperature 7.8°C). Soil respiration, soil carbon content and principal stand characteristics were measured with standardized methods. Soil CO2 fluxes were measured at each site every 15-20 days with a closed dynamic system (LI-COR 6400) using soil collars from spring 2000 to spring 2002. At the same time, soil temperature at a depth of 10 cm and soil water content (m3 m-3 ) were measured at each collar. Soil samples were collected to a depth of 30 cm and stones, root content and bulk density were determined in order to obtain reliable estimates of carbon content per unit area (kg Cm -2 ). Soil respiration and temperature data were fitted with a simple logistic model separately for each site, so that base respiration rates and mean annual soil respiration were estimated. Then the same regression model was applied to all sites simultaneously, with each model parameter being expressed as a linear function of site variables. The general model explained about 86% of the intersite variability of soil respiration. In particular, soil mean annual temperature explained the most of the variance of the model (0.41), followed by soil temperature interquartlile range (0.24), soil carbon content (0.16) and soil water content (0.05). © 2005 Blackwell Publishing Ltd. 1817 Soil carbon and microbial communities at mitigated and late successional bottomland forest wetlands D’Angelo E.M., Karathanasis A.D., Sparks E.J. et al. Wetlands 2005 25/1 (162-175) The practice of wetland mitigation has come into question during the past decade because the relative capacity of the mitigated wetlands to perform normal wetland functions is mostly unknown. In this study, we wanted to determine whether soil microbial communities were significantly different in early successional mitigated wetlands (<10 years) (ES) compared to late successional bottomland hardwood forest wetlands (LS) due to differences in 347 soil properties, such as carbon quality and storage and waterholding capacity. Carbon storage in litter and soil was 1.5 times greater in LS wetlands than ES wetlands. Soil water-holding capacity was significantly greater in LS wetlands and was related to soil organic C content (r2 =0.87, p-value=0.0007). Gravimetric water content was a moderately strong predictor of microbial respiration (r2 =0.55-0.61, p-value=0.001-0.0004) and microbial biomass (r2 =0.70, p-value=0.0019). Anaerobic microbial groups were enriched in soils from LS wetlands in both the dry and wet seasons, which suggested that LS soils were wetter for longer periods of the year than ES soils. The capacity of these wetlands to support anaerobic microbial processes depends on soil water retention characteristics, which were dictated by organic matter content. As an integrator of microbial growth conditions in soils, determination of microbial community composition by phospholipid fatty acid (PLFA) analysis may be an important new tool for monitoring successional development of compensatory mitigation wetlands. © 2005, The Society of Wetland Scientists. Contamination and remediation 1818 A method of mercury removal from topsoil using lowthermal application Kucharski R., Zielonka U., Sas- Nowosielska A. et al. Environmental Monitoring and Assessment 2005 104/1-3 (341-351) Mercury contamination in the environment is problematic due to the unusual physical properties and well-recognized toxicity of this common metal. The bioavailability of mercury depends strongly on its chemical speciation. Anthropogenic mercury and its compounds appear in soil as "hot spots" located close to industrial facilities that used or produced mercury. The nature of the chemical production process, transportation and disposal practices often determined the chemical composition and distribution of mercury in the surrounding soils. Current ex situ soil remediation methods are expensive, produce undesirable side effects to the environment and usually involve transportation of contaminated soil. In this project, sponsored by the U.S. Department of Energy, a low-cost, simple approach to removing mercury from soil was evaluated. The process uses low-temperature thermal desorption of volatile metallic mercury and its compounds, and subsequent vapor capture. The project consisted of laboratory and plot-scale experiments. The laboratory efforts evaluated theoretical calculations of mercury removal as a function of time and temperature. The plot-scale experiment was a practical application of the laboratory results. For both experiments, mercury-polluted soil was obtained from a chemical production facility located in southern Poland. In laboratory experiments, at temperature 373 K total mercury concentration decreased in soil by nearly 32%. In plot-scale experiments, at temperature 440 K, about 60-70% of total mercury was removed from the soil. At the end of the experiment, a test of soil biological activity was performed to check if the high temperature applied to the soil did not impair the soil growth properties. There was no negative effect of temperature found. © Springer Science + Business Media, Inc. 2005. 1819 The relative influence of distant and local (DEW-line) PCB sources in the Canadian Arctic Stow J.P., Sova J. and Reimer K.J. Science of the Total Environment 2005 342/1-3 (107-118) Soil PCB contamination has been delineated at 18 of 21 Distant Early Warning Line (DEW-line) stations being cleaned up by the Canadian Department of National Defence (DND). As a result, detailed surface soil delineation data has been reported for contamination exceeding 1 g/g (dw total Aroclor), which is the remedial criteria for PCB contaminated soil under the DEWline cleanup project. The results of this delineation work has allowed us to estimate the mass of PCB contained in surface soil at these sites and to quantify the DEW-line as a source of PCBs to both local and Arctic wide contamination. Our analysis of DEW-line cleanup delineation reports suggests that pre-cleanup surface soils (top 10 cm) with over 1 g/g PCB constituted a source of PCBs that ranged from 0.8 to 43 kg with a mean of 18 kg. The total mass of PCB at all 18 sites was 119 kg. Previous studies have described a "halo-effect" that surrounds 348 SOILS DEW-line sites, whereby PCB signatures in soil and plants up to 10 km from source areas were attributed to the local source. At Cambridge Bay (CAM-M), Nunavut, our inventory of PCB sources and redistribution suggests that up to 3.4 kg of PCB were exported from the site to the surrounding tundra prior to cleanup. The primary mechanism of transportation appears to be wind borne particulate. Potential vapour phase emissions of PCB from contaminated soil at DEW-line sites appears to have been negligible. Crown Copyright © 2004 Published by Elsevier B.V. All rights reserved. 1820 Filter pore size selection for characterizing dissolved organic carbon and trihalomethane precursors from soils Chow A.T., Guo F., Gao S. et al. Water Research 2005 39/7 (1255-1264) Filters with a pore size of 0.45m have been arbitrarily used for isolating dissolved organic carbon (DOC) in natural waters. This operationally defined DOC fraction often contains heterogeneous organic carbon compounds that may lead to inconsistent results when evaluating trihalomethane formation potential (THMFP). A finer pore size filter provides more homogeneous DOC properties and enables a better characterization of organic matter. In this study, we examined the effects of filter pore size (1.2, 0.45, 0.1 and 0.025m) on characterizing total organic carbon, ultra-violet absorbance at 254 nm (UV254 ) and THMFP of water extracts from a mineral and organic soil in the Sacramento-San Joaquin Delta, California. Results showed that the majority of water extractable organic carbon (WEOC) from these soils was smaller than 0.025m, 85% and 57% in organic and mineral soils, respectively. A high proportion of colloidal organic carbon (COC) in mineral soil extracts caused water turbidity and resulted in an abnormally high UV254 in 1.2 and 0.45m filtrates. The reactivity of organic carbon fractions in forming THM was similar for the two soils, except that COC from the mineral soil was about half that of others. To obtain a more homogeneous solution for characterizing THM precursors, we recommend a 0.1m or smaller pore-size filter, especially for samples with high colloid concentrations. © 2005 Elsevier Ltd. All rights reserved. 1821 Non-ionic surfactant flushing of pentachlorophenol from NAPL-contaminated soil Park S.- K. and Bielefeldt A.R. Water Research 2005 39/7 (13881396) Column studies were conducted to assess the suitability of a non-ionic surfactant Tergitol NP-10 (TNP10) for washing pentachlorophenol (PCP) from soil and non-aqueous phase liquids (NAPLs). Flushing of 50 and 200 pore volumes of 5 g/L TNP10 was required to exhaust the surfactant sorption capacity of the soil and soil plus NAPL, respectively. The sorption of surfactant to the soil in the columns was four times greater than the quantity previously observed in batch tests. Flushing with 5 g/L TNP10 removed 71-79% of the 200 mg/kg soil-sorbed PCP after 160 pore volumes compared to 0.7-2% PCP removal without surfactant. In columns additionally containing 0.2% and 0.4% PCP-contaminated heavy oil NAPL, the PCP removal efficiency after flushing 200 pore volumes of 5 g/L TNP10 was nearly 100%. Therefore, removal of the PCP was more efficient in the NAPL-containing columns, potentially due to competition of the NAPL for PCP sorption sites. Rate-limited desorption of PCP and TNP10 likely occurred. © 2005 Elsevier Ltd. All rights reserved. 1822 Influence of soil moisture on sunflower oil extraction of polycyclic aromatic hydrocarbons from a manufactured gas plant soil Gong Z., Wilke B.- M., Alef K. and Li P. Science of the Total Environment 2005 343/1-3 (51-59) The influence of soil moisture on efficiency of sunflower oil extraction of polycyclic aromatic hydrocarbons (PAHs) from contaminated soil was investigated. The PAH-contaminated soil was collected from a manufactured gas plant (MGP) site in Berlin, Germany. Half of the soil was air-dried, and the other half was kept as field-moist soil. Batch experiments were performed using air-dried and field-moist soils, and sunflower oil was used as extractant at oil/soil ratios of 2:1 and 1:1 (v/m). The experimental data were fitted to a first-order empirical model to describe mass-transfer profiles of the PAHs. Column extraction experiments were also conducted. Field-moist and air-dried soils in the column were extracted using sunflower oil at an oil/soil ratio of 2:1. In the batch experiments, PAHs were more rapidly extracted from air-dried soil than from field-moist soil. Removal rate of total PAH increased 23% at oil/soil ratio of 1:1 and 15.5% at oil/soil ratio of 2:1 after the soil was air dried. The most favorable conditions for batch extraction were air-dried soil, with an oil/soil ratio of 2:1. In the column experiments, the removal rate of total PAH from air-dried soil was 30.7% higher than that from field-moist soil. For field-moist soil, extraction efficiencies of the batch extraction (67.2% and 81.5%) were better than that for column extraction (65.6%). However, this difference between the two methods became less significant for the air-dried soil, with a total removal rate of 96.3% for column extraction and 90.2% and 97% for batch extractions. A mass-balance test was carried out for analytical quality assurance. The results of both batch and column experiments indicated that drying the soil increased efficiency of extraction of PAHs from the MGP soil. © 2004 Elsevier B.V. All rights reserved. 1823 Persistent organic pollutants in soil density fractions: Distribution and sorption strength Krauss M. and Wilcke W. Chemosphere 2005 59/10 (1507-1515) The sorption strength of persistent organic pollutants in soils may vary among different soil organic matter (SOM) pools. We hypothesized that polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were unevenly distributed and had different soil organic carbon (SOC)-water partition coefficients (KOC ) among soil density fractions. We determined the concentrations and KOC values of 20 PAHs and 12 PCBs in bulk samples and three density fractions (light, <2.0, medium, 2.02.4, and heavy, >2.4 g cm-3 ) of 11 urban topsoils (0-5 cm) from Bayreuth, Germany. The KOC values were determined using sequential extraction with methanol-water mixtures (35% and 65% methanol) at 60°C. The sum of 20 PAH concentrations in bulk soil ranged 0.4-186 mg kg-1 , and that of 12 PCB concentrations 1.2-158 g kg-1 . The concentrations of all PAHs and PCBs decreased in the order light > medium > heavy fraction. When normalized to the SOC concentrations, PAH concentrations were significantly higher in the heavy than in the other density fractions. The KOC values of the PAHs in density fractions were 3-20 times higher than those of the PCBs with similar octanol-water partition coefficients (KOW ). The KOC values of individual PAHs and PCBs varied up to a factor of 1000 among the studied soils and density fractions. The KOC values of 5- and 6-ring PAHs tended to be highest in the heavy fraction, coinciding with their enrichment in this fraction. For the other PAHs and all PCBs, the K OC values did not differ among the density fractions. Thus, there is no relationship between sorption strength and distribution among density fractions, indicating that density fractionation is not a suitable tool to distinguish among differently reactive PAH and PCB pools in soils. © 2005 Elsevier Ltd. All rights reserved. 1824 Extended X-ray absorption fine structure spectroscopy evidence for the complexation of cadmium by reduced sulfur groups in natural organic matter Karlsson T., Persson P. and Skyllberg U. Environmental Science and Technology 2005 39/9 (3048-3055) It is widely accepted that the bioavailability, toxicity, and mobility of trace metals are highly dependent on complexation reactions with functional groups in natural organic matter (NOM). In this study, the coordination chemistry of Cd in NOM was investigated by extended X-ray absorption fine structure spectroscopy. Soil organic matter (SOM) from different types of organic soils and dissolved organic matter (DOM) from an organic and a mineral soil horizon of a Spodosol and aquatic DOM from Suwannee River were investigated. In SOM samples (1000-25000 g of Cd g-1 , pH 4.6-6.6), Cd was coordinated by 1.0-2.5 S atoms at a ´ and by 3.0-4.5 0/N atoms at a distance distance of 2.49-2.55 U ´ . In DOM samples (1750-4250 g of Cd g-1 , pH of 2.22-2.25 U 5.4-6.3), Cd was coordinated by 0.3-1.8 S atoms at a distance of ´ and 3.6-4.5 0/N atoms at a distance of 2.23-2.26 U ´. 2.51 -2.56 U In both SOM and DOM samples a second coordination shell of ´. 1.7-6.0 carbon atoms was found at an average distance of 3.12 U This is direct evidence for inner-sphere complexation of Cd by SOILS functional groups in NOM. Furthermore, ion activity measurements showed that less than 1% of total Cd was in the form of free Cd2+ in our samples. Bond distances and coordination numbers suggest that Cd complexed in SOM and DOM is a mixture of a 4-coordination with S (thiols) and 4- and 6-coordinations with 0/N ligands. Given that Cd-S associations on average are stronger than Cd-O/N associations, our results strongly indicate that reduced S ligands are involved in the complexation of Cd by NOM also at native concentrations of metal in oxidized organicrich soils and in humic streams. © 2005 American Chemical Society. 1825 Sorption and related properties of the swine antibiotic carbadox and associated N-oxide reduced metabolites Strock T.J., Sassman S.A. and Lee L.S. Environmental Science and Technology 2005 39/9 (3134-3142) Carbadox (CBX) (methyl 3-[2-quinoxalinylmethylene]-carbazate N1, N4 dioxide) is a chemotherapeutic growth promoter and antibacterial drug added to feed for starter pigs. Toxicity of CBX and at least one of its metabolites (bisdesoxycarbadox; DCBX) has resulted in a number of studies regarding its stability and residence time in edible swine tissue; however, little is known on its environmental fate pertinent to the application of antibiotic-laden manure to agricultural fields. We measured sorption of CBX and DCBX by soils, sediment, and homoionic clays from 10 mM KCl and 5 mM CaCl2 solutions, sorption of two N-oxide reduced metabolites (N4 and N1) by a subset of soils from 5 mM CaCl2 , octanol - water partition coefficients (K ow ) of CBX and all three metabolites, and CBX solubility in water and mixed solvents. Sorption appeared well-correlated to organic carbon (OC) for the soils (e.g., log (Koc , L/kg OC) = 3.96 0.18 for CBX). However, sorption was enhanced in the presence of K+ , competitive sorption from the metabolites was observed, and sorption by clay minerals was large ( 105 L/kg for SWy-1). Sorption by clays was inversely correlated to surface charge density (e.g., sorption decreased from 10 5 to 10 L/kg as charge density increased from 1 to 2 mol c /m2 ), similar to what has been observed for nitroaromatic compounds. In the absence of a clay surface, hydrophobic-type forces dominated with Kow values and reverse-phase Chromatographic retention times increasing with the loss of oxygen from the aromatic nitrogens. Therefore, it is likely that both OC and clay contribute significantly to sorption of carbadox and related metabolites by soils with relative contributions most dependent on clay type. © 2005 American Chemical Society. 1826 Influence of smectite hydration and swelling on atrazine sorption behavior Chappell M.A., Laird D.A., Thompson M.L. et al. Environmental Science and Technology 2005 39/9 (3150-3156) Smectites, clay minerals commonly found in soils and sediments, vary widely in their ability to adsorb organic chemicals. Recent research has demonstrated the importance of surface charge density and properties of exchangeable cations in controlling the affinity of smectites for organic molecules. In this study, we induced hysteresis in the crystalline swelling of smectites to test the hypothesis that the extent of crystalline swelling (or interlayer hydration status) has a large influence on the ability of smectites to adsorb atrazine from aqueous systems. Air-dried K-saturated Panther Creek (PC) smectite swelled less (d(001) = 1.38 nm) than never-dried K-PC (d(001) = 1.7 nm) when rehydrated in 20 mM KCl. Correspondingly, the air-dried-rehydrated K-PC had an order of magnitude greater affinity for atrazine relative to the never-dried K-PC. Both air-dried-rehydrated and never-dried Ca-PC expanded to approximately 2.0 nm in 10 mM CaCl2 and both samples had similar affinities for atrazine that were slightly lower than that of never-dried K-PC. The importance of interlayer hydration status in controlling sorption affinity was confirmed by molecular modeling, which revealed much greater interaction between interlayer water molecules and atrazine in a three-layer hydrate relative to a one-layer hydrate. The entropy change on moving atrazine from a fully hydrated state in the bulk solution to a partially hydrated state in the smectite interlayers is believed to be a major factor influencing sorption affinity. In an application test, choice of background solution (20 mM KCl versus 10 mM CaCl2 ) and air-drying treatments significantly affected atrazine sorption affinities for three-smectitic soils; however, the trends 349 were not consistent with those observed for the reference smectite. Further, extending the initial rehydration time from 24 to 240 h (prior to adding atrazine) significantly decreased the soil’s sorption affinity for atrazine. We conclude that interlayer hydration status has a large influence on the affinity of smectites for atrazine and that air-drying treatments have the potential to modify the sorption affinity of smectitic soils for organic molecules such as atrazine. © 2005 American Chemical Society. 1827 Pot and field studies on bioremediation of p-nitrophenol contaminated soil using Arthrobacter protophormiae RKJ100 Labana S., Pandey G., Paul D. et al. Environmental Science and Technology 2005 39/9 (3330-3337) Biodegradation of p-nitrophenol (PNP), a priority pollutant, was studied as a model system for bioremediation of sites contaminated with nitroaromatic/organic compounds. Bioremediation of PNP-containing soil was first carried out in pots using immobilized and free cells of Arthrobacter protophormiae RKJ100 in order to ascertain the role of a suitable carrier material. Results showed that stability of the introduced strain was enhanced upon immobilization and that the rate of PNP depletion decreased with increasing depth of soil. Small-scale field studies (in one square meter plots) were then conducted in which PNP-contaminated soil from an agricultural field was bioaugmented with strain RKJ100 under natural environmental conditions. PNP was totally depleted in 5 days by immobilized cells, whereas free cells were able to deplete 75% of PNP in the same time period. The fate of the released strain as monitored by plate counts, hybridization studies, and real-time polymerase chain reaction revealed fairly stable population of the cells upon immobilization on corncob powder throughout the period of study. © 2005 American Chemical Society. 1828 Influence of dissolved organic matter from waste material on the phytotoxicity and environmental fate of triflusulfuron methyl Gigliotti G., Onofri A., Pannacci E. et al. Environmental Science and Technology 2005 39/19 (7446-7451) Bioassays and chemical analyses were performed to study the effect of hydrophobic dissolved organic matter (HoDOM) extracted from a municipal waste compost (MWC) on the behavior of triflusulfuron methyl in soil and water. Bioassays with oilseed rape showed that HoDOM in culture solution lowered the effective dose 50 of triflusulfuron methyl by up to 4.8 times. Equilibrium dialysis experiments showed that in aqueous solution triflusulfuron methyl was adsorbed to HoDOM (KOC of 446.5 mL g-1 ). The half-life in water (pH 7.0) was increased from 52 to 76 days in the presence of HoDOM, but this cannot completely explain its phytotoxicity, as bioassays lasted for 21 days only. On the other hand, the addition of HoDOM to soils did not change the degradative behavior of triflusulfuron methyl. Fluorescein diacetate hydrolysis showed that HoDOM in soil did not significantly influence soil microbial activity, which may explain the above result on degradation in soil. Furthermore, in batch equilibrium experiments on soil, triflusulfuron methyl was only weakly adsorbed and the presence of HoDOM significantly modified the isotherm form. Results suggest that although the addition of exogenous HoDOM from MWC to soil did not influence the herbicide’s persistence, its enhanced mobility could be of environmental concern and may deserve further research. © 2005 American Chemical Society. 1829 Assessing sequestration of selected polycyclic aromatic hydrocarbons by use of adsorption modeling and temperature-programmed desorption Abu A. and Smith S. Environmental Science and Technology 2005 39/19 (7585-7591) Sequestration of phenanthrene and pyrene was investigated in two soils-a sandy soil designated SBS and a silt-loam designated LHS-by combining long-term batch sorption studies with thermal desorption and pyrolysis of amended soil samples. The Polanyibased adsorption volume and the adsorbed solute mass increased with aging for both soils, thus demonstrating the mechanism for observed sequestration. Despite rigorous thermal analysis, 3062% (SBS sand) and 8-30% (LHS silt-loam) of phenanthrene 350 SOILS could not be recovered after 30-270 days of sorption, with the increase in desorption resistance showing greater significance in SBS sand. For both soils, these values were 20-65% of adsorbed phenanthrene mass. Activation energies estimated from the temperature-programmed desorption (TPD) of sorbed phenanthrene at 375 °C were 51-53 kJ/mol, consistent with values derived for desorption of organic compounds from humic materials. The activated first-order model fitting of observed TPD data supports the conclusion that the desorption-resistant fraction of phenanthrene has become sequestered onto condensed organic domains and requires temperatures exceeding 600 °C to be released. The work demonstrates the use of thermal analysis in complementing the Polanyi-based adsorption modeling approach for assessing the mechanistic basis for sequestration of organic contaminants in soils. © 2005 American Chemical Society. 1830 Model testing for the remediation assessment of a radium contaminated site in Olen, Belgium Sweeck L., Kany´ar B., Krajewski P. et al. Journal of Environmental Radioactivity 2005 84/2 (245-258) Environmental assessment models are used as decision-aiding tools in the selection of remediation options for radioactively contaminated sites. In most cases, the effectiveness of the remedial actions in terms of dose savings cannot be demonstrated directly, but can be established with the help of environmental assessment models, through the assessment of future radiological impacts. It should be emphasized that, given the complexity of the processes involved and our current understanding of how they operate, these models are simplified descriptions of the behaviour of radionuclides in the environment and therefore imperfect. One way of testing and improving the reliability of the models is to compare their predictions with real data and/or the predictions of other models. Within the framework of the Remediation Assessment Working Group (RAWG) of the BIOMASS (BIOsphere Modelling and ASSessment) programme coordinated by IAEA, two scenarios were constructed and applied to test the reliability of environmental assessment models when remedial actions are involved. As a test site, an area of approximately 100 ha contaminated by the discharges of an old radium extraction plant in Olen (Belgium) has been considered. In the first scenario, a real situation was evaluated and model predictions were compared with measured data. In the second scenario the model predictions for specific hypothetical but realistic situations were compared. Most of the biosphere models were not developed to assess the performance of remedial actions and had to be modified for this purpose. It was demonstrated clearly that the modeller’s experience and familiarity with the mathematical model, the site and with the scenario play a very important role in the outcome of the model calculations. More model testing studies, preferably for real situations, are needed in order to improve the models and modelling methods and to expand the areas in which the models are applicable. © 2005 Elsevier Ltd. All rights reserved. 1831 A comparison of five pesticides adsorption and desorption processes in thirteen contrasting field soils Boivin A., Cherrier R. and Schiavon M. Chemosphere 2005 61/5 (668-676) Batch adsorption and desorption experiments were performed using thirteen agricultural soil samples and five pesticides. Experimental data indicated a gradient in pesticide adsorption on soil: trifluralin 2,4-D > isoproturon > atrazine bentazone. Atrazine, isoproturon and trifluralin adsorption were correlated to soil organic matter content (r2 = 0.7, 0.82, 0.79 respectively). Conversely, bentazone adsorption was governed by soil pH (r2 = 0.68) while insignificant effect has been shown in the case of 2,4-D. Multiple linear regressions were used to combine relationships between the various soil parameters and the Freundlich adsorption coefficient (K f ) of each pesticide. Then desorption was assessed since it may reflect some of the interactions involved between the pesticides and the soil components. Adsorbed molecules were released into aqueous solution in the following order: bentazone atrazine > isoproturon > 2,4D trifluralin. The occurrence of hysteresis did not allow an accurate interpretation of the pesticide desorption data because of the possible interplay of several processes. © 2005 Elsevier Ltd. All rights reserved. 1832 Enhancement of PAH biomineralization rates by cyclodextrins under Fe(III)-reducing conditions Ramsay J.A., Robertson K., VanLoon G. et al. Chemosphere 2005 61/5 (733-740) Amendment of a soil slurry with low concentrations of a cyclodextrin, hydroxypropyl- -cyclodextrin (HPCD), (0.05-0.5 g l-1 ) increased the phenanthrene mineralization rate of a microbial consortium by 25% under Fe(III)-reducing conditions. Although a higher concentration (5.0 g l -1 ) resulted in a faster initial rate of mineralization, mineralization ceased after 25 days with maximum mineralization 17% lower than the control (no HPCD). At lower HPCD concentrations, mineralization was still taking place at day 76. Although pH should affect Fe(III) solubility, mineralization rates at pH 6.0 and 8.0 were comparable. Decreasing the temperature reduced the extent and rate of mineralization, but mineralization rates at 10°C were still 60% of that obtained at 30°C. © 2005 Elsevier Ltd. All rights reserved. 1833 Remediation of contaminated soils using supercritical fluid extraction: A review (1994-2004) Salda˜na M.D.A., Nagpal V. and Guigard S.E. Environmental Technology 2005 26/9 (1013-1032) Considerable effort is being made to remediate soils contaminated with petroleum hydrocarbons, polyaromatic hydrocarbons, polychlorinated biphenyls, dioxins, heavy metals and other organic and inorganic compounds that have resulted from industrial activities, accidental spills and improper waste disposal practices. Current remediation technologies may be limited when treating certain types of contaminated soils and therefore new, efficient and cost effective technologies are being investigated. Supercritical fluid extraction is a potential remediation technology for contaminated soils. It is a simple, fast and selective solvent extraction process that uses a supercritical fluid as the solvent. A commonly used fluid is carbon dioxide at pressures and temperatures greater than 7.4 MPa and 31°C, respectively. In supercritical fluid extraction, the extracted contaminants first dissolve into the supercritical solvent and then these contaminants are separated from the supercritical solvent via a simple change in pressure and temperature conditions or by using a separation process. This paper provides a review of supercritical fluid extraction and its application to the remediation of contaminated soils. This review focuses on the removal of organic contaminants (such as petroleum hydrocarbons, polyaromatic hydrocarbons, polychlorinated biphenyls and others) and inorganic contaminants (such as heavy metals and radioactive elements) from soils. Recent data (1994-2004) on the supercritical fluid extraction of spiked soils and field-contaminated soils were collected. The success of supercritical fluid extraction as a method for removing these contaminants from soils is highlighted and some of the future research needed to develop it as a commercial-scale economic remediation technology are discussed. © Selper Ltd., 2005. 1834 Lead and zinc extraction potential of two common crop plants, Helianthus annuus and Brassica napus Solhi M., Shareatmadari H. and Hajabbasi M.A. Water, Air, and Soil Pollution 2005 167/1-4 (59-71) Phytoextraction is a remediation technology that uses plants to remove heavy metals from soil. The success of a phytoextraction process depends on adequate plant yield (aerial parts) and high metal concentrations in plant shoots. A pot experiment was conducted to investigate the combination effects of plants [sunflower (Helianthus annuus) and canola (Brassica napus)] with soil treatments (manure, sulfuric acid and DTPA). Treatments, including two plants and seven soil treatments, which applied according to completely randomized factorial design with three replications. The largest shoot dry weight biomass production occurred in manure treatments for both plants. The maximum shoot concentrations of Pb and Zn were 234.6 and 1364.4 mg kg-1 respectively in three mmoles DTPA kg-1 treatment of sunflower. Furthermore the results showed that sunflower had a higher extracting potential for removal of Pb and Zn from polluted soil. © Springer 2005. SOILS 1835 Effects of low molecular weight organic anions on the release of arsenite and arsenate from a contaminated soil Zhang S., Li W., Shan X.- Q. et al. Water, Air, and Soil Pollution 2005 167/1-4 (111-122) Low-molecular-weight-organic-anions (LMWOAs) are important exudates of plants and may influence the mobility and bioavailability of metals or metalloids. In the present study the effects of selected LMWOAs, citrate, malate and oxalate, on the release of arsenite (As(III)) and arsenate (As(V)) in a contaminated soil were investigated. The organic anions have significant influence upon the release of arsenic from the soil, and a linear relationship exits between the released arsenic and the concentration of LMWOAs in the extractants. pH effects on the arsenite and arsenate adsorption were not significant over the range from 3 to 7. The amounts of arsenite and arsenate released were significantly correlated with the release of Fe, Mn and Al, suggesting that arsenic was mainly released from Fe-, Mn- and Al-oxides or hydroxides in soil. The ratio of released arsenite to arsenate was not influenced by LMWOAs. © Springer 2005. 1836 Potentially mobile lead fractions in montane organicrich soil horizons Kaste J.M., Friedland A.J. and Miller E.K. Water, Air, and Soil Pollution 2005 167/1-4 (139-154) Anthropogenic emissions during the 20th century resulted in global lead (Pb) contamination of soils. Recent studies have demonstrated that the organic horizons of temperate montane Spodosols in the northeastern United States retain Pb on timescales of 50 to 150 years. The precise mechanism(s) of this strong Pb partitioning to organic-rich soil material remain elusive, but a detailed understanding of Pb retention by organic layers and mineral topsoils is critical for predicting the fate of pollutants deposited on ecosystems. Here we use selective extractions to quantify potentially mobile pools of Pb in the surface horizons of relatively remote montane Spodosols from New Hampshire and Vermont. Using 10 consecutive rinses of water, we extracted a total of 1 to 5% of the carbon, and 4 to 12% of the Pb. Dialysis equilibration experiments demonstrate that this Pb is >5,000 molecular weight, and not truly dissolved as Pb 2+ . When soil was extracted with a single rinse of 0.02 M HCl (pH 1.7), 5 to 11% of the Pb was mobilized. However, hydroxylamine hydrochloride in 0.02 M HCl (a reducing agent) extracted 30 to 40% of the Pb. Repeated rinses with sodium hydroxide and sodium pyrophosphate, which target organic matter but may extract other soil phases removed 16 to 75% and 60 to 100% of the Pb, respectively. We show that significant Fe, Pb, and Al can be released from soils under reducing conditions, and that this fraction can be underestimated if sodium pyrophosphate is used in a previous step for leaching the organic-metal phase, as is typically done in sequential extraction schemes. Our results indicate that inorganic phases play an important role in determining Pb mobility and bioavailability, even in surface soil horizons dominated by organic matter. © Springer 2005. 1837 Aspergillus tubingensis reduces the pH of the bauxite residue (red mud) amended soils Krishna P., Reddy M.S. and Patnaik S.K. Water, Air, and Soil Pollution 2005 167/1-4 (201-209) Bauxite residue (red mud), a poor substrate for plant growth because of very high pH, salinity and sodicity, is required to be revegetated. The possibility of using Aspergillus tubingensis (AT1), a phosphate solubilizer in red mud amended soils to reduce the alkalinity of the red mud was studied in the present study. A. tubingensis was tested for its ability to grow at high pH and in different concentrations of aluminium (Al), iron (Fe) and sodium (Na). The results showed that A. tubingensis was able to grow at high pH and reduce the alkalinity of the nutrient medium and also to accumulate different metals in the mycelium. The pH values of the red mud amended soils were also significantly reduced (by 2-3 units) by A. tubingensis, which resulted in maize growth improvement. These results suggest that A. tubingensis plays an important role in reducing the pH of the red mud and also helps in promoting the plant growth in it. © Springer 2005. 351 1838 Comparison of plants for germination toxicity tests in petroleum- contaminated soils Banks M.K. and Schultz K.E. Water, Air, and Soil Pollution 2005 167/1-4 (211-219) Pollution of soil by petroleum hydrocarbons is a serious environmental problem world-wide. Although total concentration of contaminants in soil and/or water is used for regulatory review, it also is beneficial to assess the potential for ecosystem impact through a series of bioassays. One commonly used bioassay is seed germination. In this test, seeds are placed in contaminated material, and seedlings enumerated after a specified incubation period. However, different plant species produce variability in response. In the research project reported here, lettuce (Lactuca sativa L.), millet (Panicum miliaceum), radish (Raphanus L.), red clover (Trifolium pratense L.), and wheat (Triticum aestivum) were tested for sensitivity to petroleum-contaminated soil in germination tests. While most plants appeared to show some sensitivity to the pollutant, only lettuce had a statistically significant difference in response to contaminated and uncontaminated soil. These results confirm that Latuca sativa L is the optimal plant choice for standard germination toxicity tests with petroleum-impacted soil. © Springer 2005. 1839 Influence of water content and plants on the dissipation of chlorinated volatile organic compounds in soil Cho C., Sung K., Coapcioglu M.Y. and Drew M. Water, Air, and Soil Pollution 2005 167/1-4 (259-271) To devise effective procedures for the remediation of soil contaminated by VOCs, an improved understanding of their fate and transport mechanisms in soil is essential. To show the effect of plants on the dissipation of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE) and tetrachloroethylene (PCE), two types of experiments, vial and column, were conducted. The results suggested that keeping the soil moisture content at field capacity is desirable for VOCs dissipation. All VOCs were dissipated quickly in unplanted columns than planted conditions in early periods of the experiment because more volatilization occurred in unplanted conditions. The plants could take up and retard volatile contaminants, and prevent contamination of ambient air. Although the time for acclimation for microbial communities to contaminants for enhanced biodegradation should be considered, phytoremediation is potentially a cost-effective remediation technique for soils contaminated by volatile organic compounds (VOCs). © Springer 2005. 1840 Application of Relaxed Eddy Accumulation technique to quantify Hg 0 fluxes over modified soil surfaces Olofsson M., Sommar J., Ljungstr¨om E. et al. Water, Air, and Soil Pollution 2005 167/1-4 (331-352) Fluxes of mercury from a waste repository and from an agricultural field amended with sewage sludge were measured. The measurements were performed by utilising a Relaxed Eddy Accumulation (REA) system synchronously coupled to automated mercury cold vapour atomic fluorescence analysers (CVAFA). The waste repository was severely contaminated and fluxes of between 0.16g m -2 h-1 and 29g m-2 h-1 could be measured. Fluxes at the slightly contaminated agricultural field measured between 8 ng m-2 h-1 and 1.9g m-2 h -1 . The results showed that the REA-CVAFA system could be used for measurements above both severely-and slightly contaminated soils. The measurements at the chlor-alkali plant showed that temperature was the most important parameter controlling the release of mercury at this site. At the agricultural field, the measurements indicated that both solar radiation and temperature may have influenced the emissions. Most of the mercury added to the field was lost to the atmosphere during the summer season. © Springer 2005. 1841 An empirical model for estimating remediation costs at contaminated sites Kaufman M.M., Rogers D.T. and Murray K.S. Water, Air, and Soil Pollution 2005 167/1-4 (365-386) A model for estimating the remediation costs at contaminated sites is developed, in which the predictor variable is a composite of surface, subsurface, and contaminant risk factors. Calibration of the model is performed at 83 sites in an urbanized watershed with diverse surface geology in southeastern Michigan. These 352 SOILS test sites exhibited different extents of contamination, including some where only soil was contaminated, and others where soil and groundwater were contaminated. The model was then applied to 79 sites with multiple contamination extents within different watersheds in North America, Europe, Australia, and Africa. The results indicate a very high correlation between the estimated and actual remediation costs at these sites. This model thus has the potential for providing reliable estimates of remediation costs across a broad array of soil and groundwater contamination scenarios, including dense nonaqueous phase liquid (DNAPL) contamination in sandy soil and lead in clay soil. © Springer 2005. 1842 The influence of organic ligands on the retention of lead in soil Schwab A.P., He Y. and Banks M.K. Chemosphere 2005 61/6 (856-866) Organic acids are commonly produced and exuded by plant roots and soil microorganisms. Some of these organic compounds are effective chelating agents and have the potential to enhance metal mobility. The effect of citrate and salicylate on the leaching of lead in soil was investigated in a laboratory experiment. In short-term batch experiments, adsorption of lead to soil was slightly enhanced with increasing salicylate concentration (5005000 M) but decreased significantly in the presence of citrate. These observations suggested that citrate may enhance Pb leaching, but this was not observed in the column study. Soluble Pb in the presence and absence citrate or salicylate (up to 5000 M) was added to soil columns at a moderate flow rate, but no Pb was observed to emerge from the soil in any of the soil columns. Rapid biodegradation of citrate in soil eliminated potential complexing ability. Breakthrough of Pb from soil was noted only when using small columns at high flow rates (>20 pore volumes per day). Under these conditions of physical and chemical nonequilibrium, citrate was not degraded and significantly enhanced Pb mobility. As in the batch adsorption experiments, the presence of salicylate reduced Pb leaching. Considering the extreme conditions required to induce Pb leaching, it is likely that Pb will remain relatively immobile in soil even in the presence of a strong complexing agent such as citrate. © 2005 Elsevier Ltd. All rights reserved. 1843 Effects of Lumbricus terrestris, Allolobophora chlorotica and Eisenia fetida on microbial community dynamics in oil-contaminated soil Schaefer M., Petersen S.O. and Filser J. Soil Biology and Biochemistry 2005 37/11 (2065-2076) Oil spills are one of the most common types of soil pollution. Bioremediation has become an attractive alternative to physicochemical methods of remediation, where feasible. Earthworms have been shown to stimulate the degradation of petroleum hydrocarbons in soil, and it was hypothesized that the role of earthworms in remediation lies in the enhancement of an oil degrading microbial community. The aim of this study was to characterize microbial activity and community dynamics in oil-contaminated soil incubated with or without earthworms. Three earthworm species (Eisenia fetida, Allolobophora chlorotica and Lumbricus terrestris) were incubated in crude oil polluted soil (ca. 10,000 mg/kg total petroleum hydrocarbons (TPH)) and a reference soil for 28 d. Control treatments with manual mixing and/or cattle dung amendment were also included. In the oil-contaminated soil, respiration and concentration of microbial biomass was significantly enhanced by earthworm amendment, and TPH concentrations decreased significantly. These effects were less evident in treatments with A. chlorotica, possibly due to a difference in behavior, since individuals of this endogeic species were found in a state of inactivity (aestivation). Microbial community dynamics were described by phospholipid fatty acid (PLFA) analyses. After 28 d, similar shifts in the soil PLFA composition were observed in the oil-contaminated soil irrespective of worm species. Fungal:bacterial ratios were increased in the presence of worms, but also by addition of dung as a food source, indicating a non-specific effect of metabolizable substrates. In contrast, the fatty acids 17:1! 8 (= 9-heptadecenoic acid) and 20:4! 6c (arachidonic acid) were specifically stimulated by the presence of earthworms in the oil-contaminated soil. The results showed that earthworms can contribute positively to bioremediation of oil-contaminated soil, but that the effect may be species-dependent. © 2005 Elsevier Ltd. All rights reserved. 1844 Influence of flooding on the degradation of linuron, isoproturon and metolachlor in soil Accinelli C., Screpanti C. and Vicari A. Agronomy for Sustainable Development 2005 25/3 (401-406) Degradation of pesticides in soil usually refers to normally aerated conditions. However, considering that under some circumstances, fields treated with pesticide can be subject to flooding phenomena, more information on pesticide persistence under these conditions is needed. The main objective of the present study was to investigate the persistence of linuron, isoproturon and metolachlor in soil samples incubated under flooding conditions. During the whole incubation period, changes in soil Eh, pH and microbial C were measured. Flooding conditions produced different effects on the persistence of the three herbicides. More specifically, flooding conditions led to a significant increase in linuron and isoproturon persistence. The half-lives of linuron and isoproturon in flooded soil were 1.8 and 1.4 times higher than in nonflooded soil, respectively. An opposite phenomenon was observed with metolachlor. The half-life of metolachlor was reduced from 32.2 to 24.1 days in nonflooded and flooded soil, respectively. Soil Eh rapidly decreased in soil samples incubated under flooding conditions, passing form 368.0 mV to - 225.5 mV within the first week of flooding. No significant changes in soil microbial C in soil samples incubated under the two water regimes were observed. The results obtained from the present experiment showed that information from normally aerated soil conditions is not correctly applicable to predict herbicide persistence under flooding conditions. © INRA, EDP Sciences, 2005. 1845 Nitrogen mineralization in mine waste-contaminated soils Arslan H., G¨ulery¨uz G., Kirmizi S. and G¨uc¸er S¸. Fresenius Environmental Bulletin 2005 14/10 (900-906) In this study, the effect of mine wastes on nitrogen mineralization was investigated at two different depths of soil (0-5 cm and 5-15 cm) in waste sites in the surroundings of the Etibank Wolfram Mine Work, Bursa, Turkey. Due to the disorder of the distribution of mining wastes, the pH, CaCO3 % and element content (Fe, Mn, Zn, Mg) in the soils around the mine were enriched by mining activity. The investigation was carried out in soils taken from waste-removal pools (WRPs) and from selected sample sites which differed in their distances from the mine works. Waste materials resulted by mining were discharged with water and, they were fall down on two waste removal pools which were constructed as primitive terraces around the mine work. For this reason, elements were most enriched on sandy ground of abandoned pools. Both N-mineralization and nitrification were determined by a standard incubation method under laboratory conditions at 20°C and 60 % WHC. Mineral nitrogen was analyzed at the initial, the 21st and the 63rd day by micro-distillation method. The net mineral N production was estimated for 21 and 42 days. It was calculated as the potential mineralization rate of organic nitrogen. N-mineralization and net production were the highest at the site furthest from the mine waste site. Significant negative correlations between nitrification and element contents (Fe, Zn, Mn, Mg) of soils were also found. This shows that the mine wastes have a negative effect on the nitrogen mineralization, especially nitrification. © by PSP 2005. 1846 Evaluation of electrokinetic remediation of arseniccontaminated soils Kim S.- O., Kim W.- S. and Kim K.- W. Environmental Geochemistry and Health 2005 27/5-6 (443-453) The potential of electrokinetic (EK) remediation technology has been successfully demonstrated for the remediation of heavy metal-contaminated fine-grained soils through laboratory scale and field application studies. Arsenic contamination in soil is a serious problem affecting both site use and groundwater quality. The EK technology was evaluated for the removal of arsenic from two soil samples; a kaolinite soil artificially contaminated with arsenic and an arsenic-bearing tailing-soil taken from the Myungbong (MB) gold mine area. The effectiveness of enhancing agents was investigated using three different types of SOILS cathodic electrolytes; deionized water (DIW), potassium phosphate (KH2 PO4 ) and sodium hydroxide (NaOH). The results of the experiments on the kaolinite show that the potassium phosphate was the most effective in extracting arsenic, probably due to anion exchange of arsenic species by phosphate. On the other hand, the sodium hydroxide seemed to be the most efficient in removing arsenic from the tailing-soil. This result may be explained by the fact that the sodium hydroxide increased the soil pH and accelerated ionic migration of arsenic species through the desorption of arsenic species as well as the dissolution of arsenic-bearing minerals. © Springer 2005. 1847 Concentrations of potentially toxic metals in urban soils of Seville: Relationship with different land uses Ruiz- Cort´es E., Reinoso R., Daz- Barrientos E. and Madrid L. Environmental Geochemistry and Health 2005 27/5-6 (465-474) Fifty-two samples of surface soils were taken in the urban area of Seville, to assess the possible influence of different land uses on their metal contents and their relationship with several soil properties. The samples corresponded to five categories or land uses: Agricultural, parks, ornamental gardens, riverbanks, and roadsides. Sequential extraction of metal according to the procedure proposed by the former Community Bureau of Reference (BCR) was carried out, and pseudo-total (aqua regia soluble) metal contents were determined. Lower organic C, total N and available P and K contents were found in riverbank samples, probably due to the lack of manuring of those sites, left in a natural status. In contrast, significantly higher electrical conductivity was found in those sites, due to the tidal influence of the nearby Atlantic Ocean. Other land uses did not show significant differences in the general properties. Concentrations of Cu, Pb and Zn, both aqua-regia soluble and sequentially extracted, were clearly higher in soils from ornamental gardens, whereas the concentrations in the riverbank samples were slightly lower than the other categories. In contrast, other metals (Cd, Cr, Fe, Mn, Ni) were uniformly distributed throughout all land uses. A strong statistical association is found among the concentrations of Cu, Pb, Zn and organic C, suggesting that the larger contents of these metals in ornamental gardens are partly due to organic amendments added to those sites more frequently than to other kinds of sites. Considering the conclusions of previous studies, heavy traffic can also contribute to those ‘urban’ metals in urban soils. Periodic monitoring of the concentrations of urban metals in busy city centres and of the quality of amendments added to soils of recreational areas are recommended. © Springer 2005. 1848 A kinetic analysis of solid waste composting at optimal conditions Komilis D.P. Waste Management 2006 26/1 (82-91) Six municipal solid waste (MSW) and yard waste components (food waste, mixed paper, yard waste, leaves, branches, grass clippings) were aerobically decomposed to measure the extent of decomposition under near optimal conditions. Decomposition was characterized by at least two principal stages, for most components, as was indicated by the carbon dioxide production rates. An aerobic biodegradation conceptual model is presented here based on the principle that solids hydrolysis is the ratelimiting step during solid waste composting. The mineralizable solid carbon of each solid waste component was assumed to comprise the readily, the moderately and the slowly (or refractory) hydrolysable carbons, each hydrolyzing at different rates to aqueous (water soluble) carbon. Aqueous carbon mineralizes to CO2 at rapid rates that are not rate-limiting to the process. Solids hydrolysis rate constants were calculated after fitting the experimentally determined carbon dioxide production rate data to model results. Hydrolysis rates for the readily hydrolysable carbon in all components ranged from approximately 0.06 to 0.1 d-1 ; hydrolysis rates for the moderately hydrolysable carbon ranged from 0.005 to 0.06 d -1 . Leaves, branches and grass clippings did not have a readily hydrolysable carbon fraction, whilst the leaves and branches had the largest slowly hydrolysable carbon fractions (70%, 82%, respectively, of the total solid organic carbon). Grass and yard waste did not contain slowly hydrolysable carbon fractions. Food waste had the largest readily hydrolysable carbon fraction and produced the highest amount of CO2 among all substrates. Moderately hydrolysable solid carbon fractions 353 ranged from 16% to 90% of the total solid organic carbon for all substrates used. © 2005 Elsevier Ltd. All rights reserved. 1849 Influence of three species of arbuscular mycorrhizal fungi on the persistence of aromatic hydrocarbons in contaminated substrates Volante A., Lingua G., Cesaro P. et al. Mycorrhiza 2005 16/1 (43-50) Aromatic hydrocarbons are pollutants which have mutagenic and carcinogenic properties as well as relatively high hydrosolubility. Their presence in soils makes techniques such as bioremediation an important topic for research. In this work, the effect of arbuscular mycorrhiza (AM) on the persistence of benzene, toluene, ethylbenzene and xylene (BTEX) in artificially contaminated substrates was evaluated. Leek plants were grown with three AM fungal species using a specially designed mesocosm system, in which internal air and substrate samples were analyzed by gas chromatography for BTEX content. Strong reductions in the BTEX concentration in substrates were generally observed in the presence of mycorrhizal plants. Residual BTEX content ranged between nearly total disappearance (<2%) and 40% of the original concentration, whereas there was a high persistence of hydrocarbons in the samples of substrate alone or with nonmycorrhizal plants. These results provide first evidence for an influence of AM activity in reducing pollution of substrates by aromatic hydrocarbons. © Springer-Verlag 2005. 1850 Degradation-detoxification behavior of methamidophos in phaiozem and burozem rhizosphere (Chinese) Yu Y. and Zhou Q. Chinese Journal of Applied Ecology 2005 16/9 (1761-1764) With plastic rhizobox system, this paper studied the degradation behavior of methamidophos in the rhizosphere and non-rhizosphere of phaiozem and burozem planted with soybean. The results suggested that methamidophos could be rapidly decomposed in soil environment despite its higher acute toxicity, and its residual amount in phaiozem was generally below the level in burozem under same condition. In the absence of soybean (control), the residual amount of methamidophos at the 2nd day of incubation was about 33% in burozem, whereas only about 26% in phaiozem. An accelerated degradation of methamidophos in soybean rhizospheric soil was observed, especially in phaiozem. At the 9th day of incubation, the insecticide residue in the middle rhizobox phaiozem and burozem with soybean was decreased by 87.5% and 76.0%, respectively, compared with that of the control. The degradation process of methamidophos in soil environment followed the first-order equation, and its half-life was about 2 days. 1851 A preliminary investigation into the use of ochre as a remedial amendment in arsenic-contaminated soils Doi M., Warren G. and Hodson M.E. Applied Geochemistry 2005 20/12 (2207-2216) Ochre is an unwanted waste product that accumulates in wetlands and streams draining abandoned coal and metal mines. A potential commercial use for ochre is to remediate As contaminated soil. Arsenic contaminated soil (605 mg kg -1 ) was mixed with different ochres (A, B and C) in a mass ratio of 1:1 and shaken in 20 mL of deionised water. After 72 h As concentration in solution was ca. 500 g kg-1 in the control and 1-2.5 g kg-1 in the ochre treated experiments. In a second experiment soil:ochre mixtures of 0.05-1:1 were shaken in 20 mL of deionised water for 24 h. For Ochres A and C, as solution concentration was reduced to ca. 1 g kg-1 by 0.2-1:1 ochre:soil mixtures. For Ochre B, as concentration only reached ca. 1 g kg-1 in the 1:1 ochre:soil mix. Sorption of As was best modelled by a Freundlich isotherm using As sorption per mass of goethite in the ochre (log K = 1.64, n = 0.79, R2 = 0.76, p 0.001). Efficiency of ochre in removing As from solution increased with increasing total Fe, goethite, citrate dithionite extractable Fe and surface area. © 2005 Elsevier Ltd. All rights reserved. 354 SOILS 1852 Magnetic screening of a pollution hotspot in the Lausitz area, Eastern Germany: Correlation analysis between magnetic proxies and heavy metal contamination in soils Spiteri C., Kalinski V., R¨osler W. et al. Environmental Geology 2005 49/1 (1-9) This investigation was carried out within the scope of EU-FP5 project MAGPROX. In parallel with the work of Kalinski et al. (2004, submitted), in which the magnetic signatures of the same soil profiles were analysed in more detail. The ‘hot spot’ under investigation was situated in the Lausitz area, Eastern Germany, between two major power plants, Schwarze Pumpe and Boxberg. This heavily industrialized region is known as the Black Triangle, named after the large lignite deposits and the old-technology power plants, among other petrochemical plants, refineries, textile manufacturing and glasswork industries. The relationship between magnetic parameters and heavy metal concentrations (Fe, Mn, Zn, Pb, Cu, Cr, Cd, Co and Ni) in soil profiles was determined statistically using linear regression analysis. Strong positive correlation was observed between heavy metal concentrations as viewed preliminarily from the heavy metal and magnetic susceptibility distributions with depth (soil profiles), and from the correlation coefficients obtained. © Springer-Verlag 2005. 1853 Correlation between magnetic susceptibility and heavy metals in urban topsoil: A case study from the city of Xuzhou, China Wang X.S. and Qin Y. Environmental Geology 2005 49/1 (10-18) Anthropogenic influence, mainly due to urban and industrial activities and traffic exhaust, may affect urban topsoil via atmospheric contamination and solid waste. Magnetic susceptibility measurements were conducted on 21 urban topsoil samples from the city of Xuzhou, China. High intensities of magnetic susceptibility were detected in the majority of the samples. SEM analysis shows that magnetic minerals are in the form of spherules and mainly due to anthropogenic inputs. The heavy metals Pb, Cu, Zn, Se, Sc, Mo, Fe, and Bi show strong correlations with magnetic susceptibility, and Ag, Ba, Cd, Ni, Cr, Sb, and Sn, on the other hand, show a weak correlation with magnetic susceptibility. Whereas, of these metals studied, only Hg has no significant correlation with the susceptibility. The Tomlinson pollution load index (PLI) also shows significant correlation with the susceptibility (). The present study shows that magnetic susceptibility is a fast, inexpensive, and non-destructive method for the detection and mapping of contaminated soils. © SpringerVerlag 2005. Erosion and conservation 1854 Effects of intensifying organic manuring and tillage practices on penetration resistance and infiltration rate Thierfelder C., Am´ezquita C E. and Stahr K. Soil and Tillage Research 2005 82/2 (211-226) Soil erosion, along with the contributing factors of soil crusting and sealing, have received minimal scientific attention to date in Latin America. This study was conducted in an Andean hillside environment to determine how the local organic manuring and tillage practices influence the development of soil crusting and sealing, and the extent to which these practices influence soil water infiltration. The aim of this study was to identify treatments that prevented superficial soil structural constraints, i.e. treatments which maintain infiltration and therefore reduce potential soil erosion and run-off. Treatment results were measured with a pocket penetrometer and a mini-rain simulator on nine different cropping systems, mainly based on cassava (Manihot esculenta Crantz), from February to November 2000 and 2001. The cropping systems were laid out on a Ferrallic Cambisol, an acid, vulcanically influenced soil of the Andean region. In both cropping cycles, treatments with chicken manure application developed superficial soil crusts during the dry season. For a treatment manured with 8 t ha-1 chicken manure, this crust meant an increase in penetration resistance from 2.3 kg cm-2 in April 2000 to 16.2 kg cm-2 in July 2000. The change in superficial soil structure created a notable reduction in final infiltration from 92 to 42.2 mm h -1 . A minimum tillage treatment which dis- played the highest penetration resistance during the dry periods of up to 46.4 kg cm-2 presented no restricting effects on soil water intake (76.2 mm h-1 final infiltration in 2000) due to an optimal aggregate development during 10 years of consecutive conservation practice. Measurements of penetration resistance and infiltration showed that soil conserving treatments, such as minimum tillage and crop rotations, improved the physical soil status and prevented soil crusting developing along with its negative effects on infiltration. These methods can therefore be strongly recommended to farmers. © 2004 Elsevier B.V. All rights reserved. 1855 Effect of DEM resolutions in the runoff and soil loss predictions of the WEPP watershed model Cochrane T.A. and Flanagan D.C. Transactions of the American Society of Agricultural Engineers 2005 48/1 (109-120) Erosion prediction utilizing digital elevation models (DEMs) is a logical advancement for automating the simulation process for models such as the Water Erosion Prediction Project (WEPP). The effects of using different DEM resolutions on watershed simulations and the ability to accurately predict sediment yield and runoff from different rainfall event sizes were studied using three application methods and data from six research watersheds. Simulating watersheds with a range of resolutions can help address the problem of deciding what topographic DEM resolution is ideal for model simulations of the watershed outlet, the end of each hillslope, and along the slope profiles. The three application methods studied here were: (1) Hillslope Chanleng, (2) Hillslope - Calcleng, and (3) Flowpath. The two Hillslope methods use a representative slope profile to represent each hillslope in the watershed, and the Flowpath method uses all of the individual flowpaths as model input for WEPP simulations. Results show that the Hillslope methods were not significantly influenced by DEM resolutions; however, there was an observable interaction between resolutions and the Flowpath method. Large rainfall events were predicted better than small events, but fine DEM resolutions did not improve predictions of either large or small rainfall events. Using coarse DEM resolutions for the topographic input will not decrease the accuracy of erosion prediction using the WEPP model and the Hillslope methods, unless the coarseness of the DEM compromises the delineation of the watershed or hillslopes. 1856 Controlling soil erosion and runoff with polyacrylamide and phosphogypsum on subtropical soil Cochrane B.H.W., Reichert J.M., Eltz F.L.F. and Norton L.D. Transactions of the American Society of Agricultural Engineers 2005 48/1 (149-154) Sandy soil, prone to intense soil erosion, is used for agriculture in the subtropics of Brazil. This study was conducted to determine whether soil amendments are effective for conserving topsoil by preventing water-induced erosion on a Brazilian sandy Alfisol soil (coarse-loamy, mixed, thermic Typic Paleudalf). A programmable rainfall simulator was used at the experimental station of the Federal University of Santa Maria, in a newly harvested black oat (Avena estrigosa L.) field that was moldboard plowed and disked twice. Plots were on bare tilled soil with 8% to 12% slopes. The soil treatments consisted of a single 5 Mg ha-1 surface application of byproduct phosphogypsum (PG), a single 20 kg ha-1 surface application of anionic polyacrylamide (PAM), a combined amendment (PAM+PG) with the same rates as above, and an unamended soil (control). Simulated rainfall average intensity was 25 mm h-1 with a 2 h duration. Sediment and runoff samples were collected at intervals during the experiment, and soil surface samples inside the plot were taken after the rain for surface crusting analysis. Total soil loss was significantly lower for the treatments than for the control and averaged 197, 278, 217, and 2181 kg ha-1 , respectively for PG, PAM, PAM+PG, and control treatments. PAM and PAM+PG had steady-state runoff rates significantly less than that of the control. All of the amendments reduced soil sediment erosion (average 90% reduction) more than final runoff (average 35% reduction). Using amendments to reduce precipitation-induced erosion is a possible alternative conservation practice in this region of the world. © 2005 American Society of Agricultural Engineers. SOILS 1857 Basal sediment concentration measurement using a time domain reflectometry method Starr G.C. Transactions of the American Society of Agricultural Engineers 2005 48/1 (205-209) Sediment concentration measurement in high-concentration runoff waters is highly problematic. A novel device was developed for high-concentration measurements. This device was then used to measure sediment concentrations during monsoon runoff events at the USDA-ARS Walnut Gulch experimental watershed in southeast Arizona as an example application. Data were obtained using a 55 cm, three-prong, embedded time domain reflectometry probe and sediments in a range of size classes from the site under laboratory conditions. In the laboratory, the sensor’s concentration output was calculated using a model and the empirical function describing pure water. Without sedimentspecific calibration, laboratory validation indicated agreement with known concentrations within about 0.02 kg L-1 for sediment and water mixtures and within 0.2 kg L-1 when the probe was completely buried in 0 to 2.5 cm channel bed material. In the field application, the probe was installed in the base and center of a flume. Basal (0 to 2 cm depth) sediment concentrations were monitored during three flows with peak discharges of 5, 70, and 130 m 3 s-1 , representing small, intermediate, and large events. For the large and intermediate events, basal sediment concentrations rose from 0.4 to 1.2 kg L-1 to a plateau of 1.5 to 1.9 kg L-1 after the flow peak. The plateau extended through much of the tail of the hydrograph before falling to back to 0.4 to 1.2 kg L-1 . The small event had a similar progression but lower overall concentrations of 0.2 to 0.8 kg L -1 . These observations are consistent with a period of high sediment transport and channel erosion in the tail of monsoon runoff hydrographs. The dielectric method provides in-situ measurements in high-concentration environments where traditional methods fail. 1858 The role of impoundments in the sediment budget of the conterminous United States Renwick W.H., Smith S.V., Bartley J.D. and Buddemeier R.W. Geomorphology 2005 71/1-2 (99-111) Previous work on sediment budgets for U.S. agricultural regions has concluded that most sediment derived from accelerated erosion is still on the landscape, primarily in colluvial and alluvial deposits. Here we examine the role of small impoundments in the subcontinental sediment budget. A recent inventory based on a 30-m satellite imagery reveals approximately 2.6 million ponds, while extrapolation from a sample of 1:24,000 topographic quadrangles suggests the total may be as large as 8-9 million. These ponds capture an estimated 21% of the total drainage area of the conterminous U.S., representing 25% of total sheet and rill erosion. We estimate the total sedimentation in these small impoundments using three different methods; these estimates range from 0.43 to 1.78 109 m3 yr-1 . Total sedimentation in 43,000 reservoirs from the National Inventory of Dams is estimated at 1.67 109 m3 yr-1 . Total USLE erosion in 1992 was 2.4 109 m3 yr-1 , and export to coastal areas is estimated at 0.6 109 m3 yr-1 . Total sedimentation in impoundments is large in relation to upland erosion, in apparent contradiction to previous studies that have identified colluvial and alluvial deposition as the primary sinks. Several alternative hypotheses that could help explain this result are proposed. Regardless of which of these alternatives may prove to be the most significant in any given setting, it is clear that most sedimentation is now taking place in subaqueous rather than subaerial environments, and that small impoundments are a major sediment sink. © 2005 Elsevier B.V. All rights reserved. 1859 The implications of changes in population, land use, and land management for surface runoff in the Upper Nile Basin Area of Ethiopia Hurni H., Tato K. and Zeleke G. Mountain Research and Development 2005 25/2 (147-154) Much concern has been raised about population increase in the highlands of Ethiopia and its potential to decrease runoff from the upper Nile Basin to the lowland countries of Sudan and Egypt. The present article examines long-term data on population, land use, land management, rainfall, and surface runoff rates from small test plots (30 m2 ) and micro-catchments (73-673 ha) in the highlands of Ethiopia and Eritrea, Although the data were 355 generated only on small areas, the results of the analyses can nevertheless be used to draw some conclusions relevant to the highland-lowland water controversies that have persisted in this particular region for many decades. The data indicate that there have been no significant trends over the long term in total annual rainfall in the highlands over the past 30-50 years. Nevertheless, test plot surface runoff rates are clearly influenced by land use and soil degradation, and hence by population density and duration of agriculture. In effect there is 5-30 times more surface runoff from cultivated or degraded test plots than from forested test plots. Analysis and interpretation of data support the hypothesis that surface runoff and sediment yield from the Ethiopian and Eritrean highlands into the upper Nile Basin have most probably increased in the long term due to intensified land use and land degradation induced by population increase, when seen in a historical perspective. Rates of base flow, in turn, must have decreased during the same period, but to a much lesser extent, although conclusive empirical evidence cannot be gained from this experimental setting. One can assume that soil and water conservation measures aiming to ensure long-term livelihoods in the humid to sub-humid highlands will, on the one hand, barely affect overall catchment runoff to the downstream areas, though they will considerably reduce surface runoff and soil loss on slopes as well as river sedimentation rates. On the other hand, in a semiarid catchment where intensive soil and water conservation was carried out, reduction in runoff rates was more pronounced. It can be concluded that population increase in the Ethiopian highlands increased overall runoff rates to lowland areas in earlier times, while recent efforts to conserve watersheds might affect total runoff rates in catchments only in semiarid parts, and much less in humid parts of the Ethiopian highlands. 1860 Surface erosion assessment in two Calabrian basins (southern Italy) Antronico L., Coscarelli R. and Terranova O. IAHS-AISH Publication 2005 -/299 (16-22) The present study presents an assessment of the erosion for two basins located on the Ionian side of southern Calabria (southern Italy). Two different approaches are considered to evaluate soil erosion: a qualitative method, based on aerial photo interpretative analysis, and a quantitative method, based on the RUSLE model. The percentage of area affected overall by surface erosion proves to be greater using the quantitative approach (38.5%) compared to the qualitative (13.3%). The mean erosion estimated using RUSLE is about 3.5 mm year-1 and can be compared with the values for Calabria reported in the literature. The application of the two approaches has shown that the spatial-temporal distribution of the parameters influencing the erosive process plays a relevant role. 1861 Gully erosion: Impacts, factors and control Valentin C., Poesen J. and Li Y. Catena 2005 63/2-3 (132-153) Gully erosion attracts increasing attention from scientists as reflected by two recent international meetings [Poesen and Valentin (Eds.), Catena 50 (2-4), 87-564; Li et al., 2004. Gully Erosion Under Global Change. Sichuan Science Technology Press, Chengu, China, 354 pp.]. This growing interest is associated with the increasing concern over off-site impacts caused by soil erosion at larger spatial scales than the cultivated plots. The objective of this paper is to review recent studies on impacts, factors and control of gully erosion and update the review on ‘gully erosion and environmental change: importance and research needs’ [Poesen et al., 2003. Catena 50 (2-4), 91-134.]. For the farmers, the development of gullies leads to a loss of crop yields and available land as well as an increase of workload (i.e. labour necessary to cultivate the land). Gullies can also change the mosaic patterns between fallow and cultivated fields, enhancing hillslope erosion in a feedback loop. In addition, gullies tend to enhance drainage and accelerate aridification processes in the semi-arid zones. Fingerprinting the origin of sediments within catchments to determine the relative contributions of potential sediment sources has become essential to identify sources of potential pollution and to develop management strategies to combat soil erosion. In this respect, tracers such as carbon, nitrogen, the nuclear bomb-derived radionuclide 137 Cs, magnetics and the strontium isotopic ratio are increasingly used to fingerprint sediment. Recent studies conducted in Australia, China, Ethiopia 356 SOILS and USA showed that the major part of the sediment in reservoirs might have come from gully erosion. Gullies not only occur in marly badlands and mountainous or hilly regions but also more globally in soils subjected to soil crusting such as loess (European belt, Chinese Loess Plateau, North America) and sandy soils (Sahelian zone, north-east Thailand) or in soils prone to piping and tunnelling such as dispersive soils. Most of the time, the gullying processes are triggered by inappropriate cultivation and irrigation systems, overgrazing, log haulage tracks, road building and urbanization. As exemplified by recent examples from all over the world, land use change is expected to have a greater impact on gully erosion than climate change. Yet, reconstructions of historical causes of gully erosion, using high-resolution stratigraphy, archaeological dating of pottery and 14 C dating of wood and charcoal, show that the main gully erosion periods identified in Europe correspond to a combination not only of deforestation and overuse of the land but also to periods with high frequency of extreme rainfall events. Many techniques have proved to be effective for gully prevention and control, including vegetation cover, zero or reduced tillage, stone bunds, exclosures, terracing and check dams. However, these techniques are rarely adopted by farmers in the long run and at a larger spatial scale because their introduction is rarely associated with a rapid benefit for the farmers in terms of an increase in land or labour productivity and is often contingent upon incentives. © 2005 Elsevier B.V. All rights reserved. 1862 Monitoring of gully erosion on the Loess Plateau of China using a global positioning system Wu Y. and Cheng H. Catena 2005 63/2-3 (154-166) With the development of a technique, global positioning system (GPS) has become progressively less expensive, lighter and easier to use. The accuracy of GPS has been improved and it appears applicable to the continuously monitoring morphology changes on the earth surface with small and slow change. The objective of this study is to use GPS to measure the morphology of gullies in a small catchment near Suide, Shaanxi Province, China. There are three main gully types in the study area: bank gullies, floor gullies, and hill slope gullies, and this study mainly focuses on the hill slope gullies. The hill slope gullies in the study area are mainly discontinuous and are developing rapidly. The gully density in the study area is very large. The retreat rate of hill slope gullies is 0.16-2.02 m year-1 . The relationships between the upslope drainage area (A) and the critical slope gradient (S) for hill slope gullies is S = 0.1839A-0.2385 . The values of AS2 range from 41 to 814 m2 for the hill slope gully headcuts, and most of them fell into the range of 100-300 m2 . Both of these relationships are suggested as indexes for estimating the location of gully headcuts. © 2005 Elsevier B.V. All rights reserved. 1863 Spatial and temporal assessment of linear erosion in catchments under sloping lands of northern Laos Chaplot V., Coadou Le Brozec E., Silvera N. and Valentin C. Catena 2005 63/2-3 (167-184) Linear erosion (LE), including rilling and gullying, has been identified as the major problem for sustainable agriculture in steepland areas. It causes severe environmental, economic, and social impacts. This issue is even more crucial in those areas undergoing rapid changes in land use, as for example northern Laos, and may dramatically affect soil conservation. Despite an increasing interest in the sloping lands of tropical areas, field evaluations of LE are still infrequent. Furthermore, the controlling environmental factors of topography, land use, climate and soils at the catchment level are seldom analysed. Our main objective was to quantify the spatial and temporal variations of LE at the catchment level and at a yearly basis. The study was conducted in a 0.62 km2 watershed of Laos (Luang Prabang province) representative of the slash and burn systems of sloping lands. Linear erosion was monitored from 2001 to 2003 within 9 sub-catchments of differing surface areas, topographic characteristics and land use. The length, depth and width of the linear erosion features were recorded every 5-m from their headcuts to their outlets in order to estimate the total catchment LE. 52 linear features, mainly rills, were formed or developed within the study area with a mean erosion rate of 1.3 Mg ha-1 y-1 . LE rates ranged between 0.1 Mg ha-1 y-1 in 2003 to 2.4 Mg ha-1 y -1 in 2001. LE features mostly occurred within croplands where erosion rates reached 18 Mg ha-1 y-1 . In 2001 and 2002 there was a significant correlation between LE and the proportion of the catchment area under crops (r = 0.88 and r = 0.69, respectively). However this was not the case in 2003 when few rills developed. In 2002 only, LE correlated well with the catchment surface area, the mean slope gradient and the sub-catchment perimeter confirming the non-constancy of LE landscape relation under varying rainstorm conditions. A linear regression model for LE prediction at the catchment level, generated from 2001 data, was able to explain 78% of LE variance for the 9 sub-catchments. However, this model was unable to predict accurately LE for 2002 and 2003 (ME > 5 Mg ha-1 y-1 ). This method for quantifying the linear erosion at the catchment level and some of its controlling factors can also be used for prediction over larger areas since topography and land use data, closely correlated with LE, are easily accessible. © 2005 Elsevier B.V. All rights reserved. 1864 Gully incision as a key factor in desertification in an arid environment, the Negev highlands, Israel Avni Y. Catena 2005 63/2-3 (185-220) Gully incision has been eroding the alluvial sediments and loess soils deposited and developed along the valleys in the arid and semiarid regions of Israel. This phenomenon is critical in the arid regions of the Negev Highlands where the agricultural fields, the main floral biomass and the areas which have the highest grazing value, are limited to narrow valleys filled with redeposited loessial sediments. The headcut migration and gully development in the region were studied between 1990 and 2001 in three representative drainage basins (Zipporim, Revivim and Sekher). During flood events, the runoff penetrates the alluvial cover of the valleys, forming vertical headcuts, which gradually retreat up the valley. The runoff is channeled into narrow gullies, preventing the floodwater from spreading over the whole width of the valley. The change in irrigation efficiency along the valleys is reflected in a sharp estimated drop of 70-90% in the floral biomass, causing the reduction of the range value by 83-99%. During the monitoring time interval (1990-2001), the linear gully retreat in the study area ranged between 12.3 and 250 m an average rate of 1.12-22.7 m year-1 for each gully head. The process is accompanied by erosion of soil, which has high agricultural and range value. The total soil losses in these sites ranged between 800 and 9000 m3 at an average rate of 81-818 m3 year-1 for each gully head, which is equivalent to 121-1227 Mg year-1 . During the monitoring period, approximately 0.110.87 ha of land lost its agricultural and range value in each basin under study, at an average rate of 0.01-0.079 ha year-1 . Since the Byzantine period (1400 BP), approximately 6.5 ha, which is 10% of the land that had high agricultural and range value in the Zipporim valley, lost its value due to gully erosion. No recovery effects of the gully channels were found in the nearby region. The soil erosion is generated by a long-term natural dynamic change in the soil / rock ratio evolving within the drainage basins through time since the termination of the last glacial phase. The loessic sediments, originally deposited within the drainage basins during the late Pleistocene glacial stage, are being removed under the present Holocene climate in several erosion stages. This ongoing phenomenon is causing degradation of soil and biomass and is severely reducing the agricultural and range potential of the region. These parameters indicate that an ongoing process of desertification is active in the arid environment of the Negev Highlands, and is advancing in proportion to the headcut retreat rates in the region. The soil erosion and headcut retreat have been active in the Negev Highlands for the last few millennia. If these processes continue in the future, the Negev Highlands region will lose its agricultural potential within a few millennia. However, the fact that the ancient inhabitants of the region implemented successful long-term land conservation techniques already 3000 years ago, implies that a sustainable land management policy can be adapted to the Negev Highlands, as well as to other semi-arid regions in the Middle East. © 2005 Elsevier B.V. All rights reserved. 1865 Rapid development and infilling of a buried gully under cropland, central Belgium Vanwalleghem T., Bork H.R., Poesen J. et al. Catena 2005 63/2-3 (221-243) Analysis of contemporary and past gully erosion and infilling SOILS processes allowed to reconstruct the long-term evolution of a permanent gully system under cropland. An active and a buried gully under cropland were investigated. The recent sediment deposits within the active gully, adjacent to the buried gully, showed that the recent gully was filling in at a mean rate of 6.4 cm a -1 . In the buried gully, several erosion and deposition phases could be identified and the type of deposited sediments revealed a complex infilling history. Charcoal, pottery and brick fragments of different sizes were found at all depths of the gully infilling. Their age indicates that the first gully incised after the midst of the 17th century, most probably in the second half of the 18th century or the early 19th century. Gully morphology and analogy with the processes in the recent gully indicate that the buried gully filled in rapidly. Overall, five cycles of cut and fill occurred in 350 years or less and four cycles even within little less than a few decades, indicating that gully development and infilling under cropland can be very rapid processes. © 2005 Elsevier B.V. All rights reserved. 1866 History, origin and extent of soil erosion on Easter Island (Rapa Nui) Mieth A. and Bork H.- R. Catena 2005 63/2-3 (244-260) The isolated Easter Island (Rapa Nui) is an outstanding example of land degradation caused by land use in a sensitive ecosystem. The focus of the investigation was placed on Poike peninsula, the most eastern part of Rapa Nui. While Poike peninsula was once supplied with fertile soils, in large areas desertification takes place today. Detailed analysis of soil profiles allowed the reconstruction of the history and of causes and effects of soil erosion and gullying in the context of land use history and cultural evolution. The results of the stratigraphic analysis prove that from the beginning of human settlement around AD 300/600 until AD 1280 the agriculture on Poike peninsula was characterised by sustainable land use and a traditional type of agro-forestry. Soil erosion was not significant. At around AD 1280 the woodland on Poike, dominated by the endemic palm Jubaea sp., was cleared by slashing and burning. Intensive farming on the upper slopes of the volcanic peninsula resulted in sheet erosion lasting until the 20th century. Settlements and ceremonial places which were built around AD 1300 on downslope areas were buried soon by sediments. Agriculture ceased around AD 1400 on downslope areas as the fertile soils were completely eroded. From AD 1400 until the late 19th century sheet erosion and the accumulation of fine-layered sediments migrated upslope. On average 8.6 Mg of soil per hectare and per year were reworked by erosion (eroded and accumulated within the catchment). Gullying began on Rapa Nui with the sudden increase in the number of sheep during the early 20th century. Gullies are still developing on the island and their ongoing enlargement created extended badlands on Poike which pose a significant problem for ecological and archaeological conservation strategies. Gullying rates exceed 190 Mg ha -1 y-1 . © 2005 Elsevier B.V. All rights reserved. 1867 Runoff and erosion in the Black Marls of the French Alps: Observations and measurements at the plot scale Mathys N., Klotz S., Esteves M. et al. Catena 2005 63/2-3 (261-281) The experimental basins of Draix in the southern French Alps have been monitored since 1984 in order to quantify and analyse the incidence and patterns of erosion in the badlands developed on Black Marl formations. In order to analyse the rainfall-runoff behaviour of the mudstone slopes, rainfall simulations were conducted on small plots 1 m2 in area. Four different local geomorphologic conditions were selected for the experiments: (a) steep slope parallel or (b) perpendicular to the bedding, (c) moderate slope and (d) gravel-covered surface, both parallel to the bedding. Rainfall simulations were performed at a moderate intensity (12-25 mm h-1 ) for 30 min on three plots in each location. Different delays between simulations offered different initial soil wetnesses. A simulation during high-intensity rainfall (90-150 mm h-1 ) for 30 min was made on one plot of each type. One plot of each type was selected for monitoring during the following summer and autumn. In dry conditions, runoff was low or negligible. A second simulation carried out 1 day later again produced very low runoff coefficients. Runoff increased slightly when the interval between rainfall simulations was reduced to 30 min. In this case, a few grams of sediment were eroded, 357 whereas no erosion was observed in the first two cases. Under high-intensity conditions, runoff began quickly and the runoff coefficients were high (20-50%). Erosion was notable, but not significantly different from dry conditions. The behaviour was very different during natural rainfall events, in particular summer storms: even if the mean rainfall intensity was lower than 60 mm h-1 in 30 min, short periods of high intensity (more than 100 mm h-1 in 5 min) revealed substantial erosion activity: more than 700 g m-2 on all the plots for a rainfall event of 54 mm in 3 h and more than 600 g m -2 for an event producing 26 mm. However, the runoff coefficients were on the same order as those of the last experiment under high-intensity conditions (32-55%). The rainfall intensity over the short duration and the kinetic energy of the raindrops were the main factors influencing particle detachment and movement. 1868 Stochastic components in the gully erosion modelling Sidorchuk A. Catena 2005 63/2-3 (299-317) The great complexity of the geo-mechanical, structural, and electro-chemical forces in soil, as well as of initial and boundary conditions in the equations of hydrodynamics, leads to a necessity of spatial/temporal averaging of deterministic equations related to soil behaviour. The stochastic terms, which appear in the equations after averaging procedures, must be incorporated into the modelling of erosion features. In this study, a new method of estimating detachment rate was used in stochastic gully erosion modelling. It is based on estimation of the probability of excess of driving forces above resistance forces in the interaction of water flow and structured soil. Knowledge of the probability density functions for the flow and soil main characteristics (as flow velocity, soil cohesion, aggregate size and others) makes it possible to calculate theoretically the rate of cohesive soil erosion for any combination of these stochastic variables. The proposed theory allows explicit explanation of relationships between detachment rate and flow/soil characteristics. Detachment rate increases with flow velocity more rapidly for soil with higher cohesion and larger aggregates. This theory also shows great difference in type of soil erosion for relatively high and relatively low flow velocities, and explains rather high errors in calculating of soil erosion rate even with detailed models. © 2005 Elsevier B.V. All rights rserved. 1869 Dynamic modelling for linear erosion initiation and development under climate and land-use changes in northern Laos Chaplot V., Giboire G., Marchand P. and Valentin C. Catena 2005 63/2-3 (318-328) Linear erosion (LE) induced either by piping or overland flow is one of the most active factors in the evolution of soils. During single storm events LE may remove enormous amounts of soil material from the uplands to the bottomlands and has thus become a broad challenge for food supply, food security, and human health. Recent and rapid changes in land-use and climate patterns in the sloping lands of tropical areas may dramatically increase LE. Our main objective was to investigate to what extent one could use direct flow velocity estimations from dynamic models for predicting LE initiation and development at the event level. The second objective was to estimate the impact of expected landuse and climate changes on LE. The study was conducted in the 0.62 km 2 watershed of northern Laos presented inChaplot et al. (2005). Field observations of the formation and the development of LE features throughout 2001 were compared to flow velocity estimations from an existing surface water routing algorithm developed at Utrecht University ([De Roo, A.P.J., Wesseling, C.G. and Ritsema, C.J. 1996. LISEM: a single event physically based hydrologic and soil erosion model for drainage basins. I: theory, input and output. hydrological processes 10 (8): 1107-1117.]). In 2001, two main rainfall events were responsible for the formation or development of 14 linear features with a total length of 972 m and an erosion rate of 3.5 Mg ha-1 . The water routing algorithm was calibrated using the water and the sediment hydrographs observed at the watershed outlet during the first rainfall event. Assuming realistic estimations of flow velocity in hillslopes, a threshold of 0.062 m s-1 for linear erosion estimated over 10-m cells was defined. This threshold, validated using the remaining rainfall event, accurately predicted the length (mean error of estimate of less than 15%) and location of LE features. 358 SOILS Using this simulation tool, an increase of the percentage of land under cultivation from 9% to 100% resulted in 600% increase in linear erosion. The tested scenarios of climate changes had less impact on linear erosion. © 2005 Elsevier B.V. All rights reserved. 1870 Soil erosion and sediment deposition in the Belgian loess belt during the Holocene: Establishing a sediment budget for a small agricultural catchment Rommens T., Verstraeten G., Poesen J. et al. Holocene 2005 15/7 (1032-1043) A method to establish a Holocene sediment budget for a 103 ha agricultural catchment representative for the Belgian loess belt is presented. Soil erosion and sediment deposition were determined based on 185 coring locations and a large excavation in the valley bottom. Results were integrated in a GIS and interpolation techniques applied to derive spatial patterns of erosion and sedimentation. Total soil erosion, sediment deposition and sediment export were calculated and the results show that volumes are highly dependent on the interpolation technique used. Sediment delivery ratios between 20% and 42% are derived and are consistent with data reported in previous studies. This clearly shows that the majority of the sediments produced during the Holocene have been stored near their source area and have not been delivered to the downstream rivers. The spatial distribution of soil erosion and sediment deposition within the catchment is strongly dependent on slope gradient and position within the catchment, which suggests that, since human impact began, topography has been the main factor determining longterm soil erosion and sedimentation. © 2005 Edward Arnold (Publishers) Ltd. 1871 Kinematics of flow within headcut scour holes on hillslopes Bennett S.J. and Alonso C.V. Water Resources Research 2005 41/9 (1-12) [1] The development and migration of headcuts in rills and gullies can adversely impact soil resources in agricultural areas and accelerate landscape degradation worldwide. Analytical treatments of this erosion process have been based on a turbulent impinging jet analogue, though partially validated by field and laboratory data. Experiments were conducted using fixed headcut models to define the mean flow structure within these erosional features and to assess the applicability of similarity arguments for jets to characterize this flow domain. These data show that (1) flow within headcut scour holes is analogous to plane turbulent reattached wall jets and (2) similarity arguments used to define the limits, length scales, and velocity distributions in classical free jets and wall jets are applicable within discrete regions of the headcut scour hole domain but are affected by the ventilation characteristics of the overfall. This study contributes new knowledge on the hydrodynamics within headcut scour holes, and it confirms the applicability of jet theory for analyzing such soil erosion processes. Copyright 2005 by the American Geophysical Union. 1872 An adaptive management process for forest soil conservation Curran M.P., Maynard D.G., Heninger R.L. et al. Forestry Chronicle 2005 81/5 (717-722) Soil disturbance guidelines should be based on comparable disturbance categories adapted to specific local soil conditions, validated by monitoring and research. Guidelines, standards, and practices should be continually improved based on an adaptive management process, which is presented in this paper. Core components of this process include: reliable monitoring protocols for assessing and comparing soil disturbance for operations, certification and sustainability protocols; effective methods to predict the vulnerability of specific soils to disturbance and related mitigative measures; and, quantitative research to build a database that documents the practical consequences of soil disturbance for tree growth and soil functions. 1873 Enhanced dust deposition by trees recently established on degraded rangeland McGowan H. and Ledgard N. Journal of the Royal Society of New Zealand 2005 35/3 (269-277) Results from 2 years of dust deposition monitoring in a 10-yearold Pinus nigra plantation near Lake Tekapo are presented. They show that recently established plantations significantly enhance dust deposition rates. This could reverse a cycle of soil loss and enhance vertical accretion of soil, which would provide more options for future land use. However, observations indicate that even under such enhanced conditions for soil formation, it would take several thousand years to replace the soil lost to erosion since European farming practices were first introduced to the northern section of the Mackenzie Basin. 1874 Response of sediment production to land-use change in Luergou watershed of Loess Plateau (Chinese) Zhang Z., Wang S., Sun G. et al. Chinese Journal of Applied Ecology 2005 16/9 (1607-1612) The study on the effects of different land use patterns on the sediment production in Luergou watershed of Loess Plateau indicated that in comparing with 1982, the areas of forest and grass and of terrace in 1989 increased by 5% and 2.09%, respectively, while that of slope plowland decreased by 1.5%, with the area of naked land and shrubbery respectively increased and decreased a little. During 1998-2000, with the increase of vegetation cover and the decrease of steep slope plowland, the sediment production reduced significantly under high precipitation, 85 326 and 52 937 t under the precipitation of 803 and 786 mm, respectively, and not distinguishable in dry years. The reduction effect had a strong seasonality, which consisted with rainfall distribution. For example, in a month with 50 mm precipitation, the mean daily sediment concentration was reduced by 6 kgm-3 , while in a month with 100 mm precipitation, the reduction was 12 kgm-3 . Rainfall intensity also played an important role in soil erosion and sediment production, regardless of land use conditions. 1875 Effects of forest vegetation on runoff and sediment production on sloping lands of Loess area (Chinese) Zhang X., Yu X., Wu S. et al. Chinese Journal of Applied Ecology 2005 16/9 (1613-1617) Based on the 1985-2003 fixed-position data in 9 runoff plots of Caijiachuan watershed in the Jixian county of Shanxi Province in loess area, this paper discussed the relationships between vegetation and runoff and sediment production on sloping lands of loess area. The results showed that natural-secondary forest had better function in soil and water conservation than artifical Robinia pseudoacacia forest, with runoff and sediment produced 65%82% and 23%-92%, respectively. Multiple regression analysis indicated that runoff and sediment production had a significant correlation with rainfall and its intensity, but this relationship was decreased gradually with increasing canopy density. Different land-use type had different runoff and sediment production, e. g., Ostryopsis davidiana and natural-secondary forests had the least runoff and sediment production, artificial Robinia pseudoacacia and Pinus tabulaeformis forests had 5 folds of it as much as Ostryopsis davidiana forest, mixed apple trees and crops had 17.14 and 3.96 folds of it than Ostryopsis davidiana forest, respectively, while high-standard soil preparation could decrease the production obviously. Gray correlation analysis suggested that the stand canopy density and the biomass of herb and litter were the most important factors affecting the runoff and sediment production on sloping land, whose gray correlation degrees all exceeded 0.6. Mixed forest with multi-layer stand structure and shrub forest should be developed in vegetation re-construction of loess area, which could help to increase the coverage and litter thickness to dramatically decrease the runoff and sediment production on sloping land. 1876 Mechanism of watershed soil erosion control by vegetation (Chinese) Qin F., Yu X., Zhang M. and Xie Y. Chinese Journal of Applied Ecology 2005 16/9 (1618-1622) From the view of hydrodynamics, this paper studied the acting mechanism of tree, grass and forest litter on slope runoff velocity and kinetic energy. The results showed that slope runoff head loss was related to slope gradient, forest density, net rainfall intensity and slope length. The relationship of water head loss with the distance among trees and the diameter at the ground of tree was E / (D/b)4/3 . The grass on slope turned to be curved with s flowing, and thus, increased the bottom resistance of flow, and reduced the HYDROLOGY shearing stress of soil surface. Therefore, silt-carrying capacity decreased dramatically. The analysis of actually measured materials of each rainfall, runoff and sediment, and the comparison of Qiaozi eastern gully and Qiaozi west gully in Tianshui city of Gansu Province showed that under same precipitation condition, the runoff, sediment yield, flood peak discharge and maximum sediment transport rate in treated watershed was less than those in untreated watershed, suggesting that vegetation was obviously beneficial to water reservation and water and soil conservation. 1877 Soil properties and water holding capacities of Michelia macclurei, Schima superba and Castanopsis fissa stands (Chinese) Xue L., Li Y., Qu M. et al. Chinese Journal of Applied Ecology 2005 16/9 (1623-1627) The study showed that the soil density, total porosity, natural water capacity and capillary moisture capacity were 1.19 gcm-3 , 56.73%, 15.7% and 43.2% in Michelia macclurei stand, 1.26 gcm-3 , 54.18%, 13.0% and 37.8% in Schima superb stand, and 1.06 gcm-3 , 60.74%, 19.4%, and 45.8% in Castanopsis fissa stand, respectively. Soil water holding capacity and aeration were good in Castanopsis fissa stand but bad in Schima superba stand, whereas Michelia macclurei stand had a medium water holding capacity and a bad aeration. The water holding capacity of litter per tree was in order of Michelia macclurei (20 kg) > Castanopsis fissa (15 kg) > Schima superba (8 kg), whereas that of litter in stand was Castanopsis fissa (17 thm-2 ) > Michelia macclurei (16 thm-2 ) > Schima suPerba (13 thm-2 ). The nutrient storage of litter per tree was 112.71, 31.20 and 87.30 g in Michelia macclurei, Schima superba and Castanopsis fissa stands, respectively, and that of litter in stand was 84.35, 51.86 and 98.11 kghm-2 , respectively. The soil in the three stands was strong acidic, and the content of soil organic matter, total N, total P, total K, alkalized N, available P and available K was 18.43 g. kg-1 , 0.69 gkg-1 , 0.17 gkg-1 , 5.83 gkg-1 , 45.67 mgkg-1 , 0.83 mgkg-1 and 23.13 mgkg-1 in Michelia macclurei stand, 13.40 gkg-1 , 0.68 gkg-1 , 0.20 gkg-1 , 12.32 gkg-1 , 40.78 mgkg-1 , 0.85 mgkg-1 and 90.63 mgkg-1 in Schima superba stand, and 28.50 gkg-1 , 0.97 gkg-1 , 0.23 gkg-1 , 18.77 gkg-1 , 73.40 mgkg-1 , 1.45 mgkg-1 and 66.50 mgkg-1 in Castanopsis fissa stand, respectively. Soil bacteria accounted for > 94% of soil microbes, and their individuals were 41105, 34104 and 5.3104 g-1 in Michelia macclurei, Schima superba and Castanopsis fissa stands, respectively. The activities of soil urease, catalase and phosphatase in Castanopsis fissa stand were the greatest among the three stands, while soil cellulase activity in Michelia macclurei stand was greater than that in other two stands. In a word, soil fertility of Castanopsis fissa stand was the highest among three test stands. 1878 Landscape pattern and its functioning after ecological reconstruction in black soil region of northeast China (Chinese) Wei J. and Xiao D. Chinese Journal of Applied Ecology 2005 16/9 (1699-1705) Taken Baiquan County in Heilongjiang Province as a case, this paper studied the effects of regional ecological reconstruction on agricultural landscape pattern and its functioning in soil and water conservation, with the spatial expression and quantity identification investigated based on Geographic Information System (GIS) and field data. The landscape pattern index in class scale, transition matrix of landscape elements, macrostructure of shelterbelt networks, and spatial distribution and hydrological characteristic of reservoirs and ponds in 1989 and 2002, as well as the effects of landscape pattern and its spatial configuration change on soil and water loss were compared. The results showed that artificial ecological reconstruction changed the quantity and spatial configuration of landscape patterns in regional scale, and exerted a significant effect on soil and water conservation. From 1989 to 2002, farmland area reduced 24 731.01 hm2 , while forest land, grassland and water area increased 11 728.56, 1 838.97 and 1 190.97 hm2 , respectively. The controlled eroded land increased by 55%, and the shelterbelt-protected farmland increased by 82.2%. The number and storage capacity of reservoirs and ponds added up to 1 490 and 2.4 108 m3 , respectively, and 43.7% of intercepted surface runoff of whole landscape was collected. 359 1879 Soft-ridged bench terrace design in hilly loess region (Chinese) Cao S., Chen L. and Gao W. Chinese Journal of Applied Ecology 2005 16/8 (1443-1449) Reconfiguration of hillside field into terrace is regarded as one of the key techniques for water and soil conservation in mountainous regions. On slopes exceeding 30°, the traditional techniques of terracing are difficult to apply as risers(i. e., backslopes), and if not reinforced, are so abrupt and easy to collapse under gravity alone, thus damaging the terrace. To improve the reconfiguration of hillside field into terrace, holistic techniques of soft-ridged bench terrace engineering, including revegetation with trees and planting grasses on riser slopes, were tested between 1997 and 2001 in Xiabiangou watershed of Yan’an, Shaanxi Province. A "working with Nature" engineering approach, riser slopes of 45°, similar to the pre-existing slope of 35°, was employed to radically reduce gravity-erosion. Based on the concepts of biodiversity and the principles of landscape ecology, terrace benches, bunds, and risers were planted with trees, shrubs, forage grasses, and crops, serving to generate a diverse array of plants, a semiforested area, and to stabilize terrace bunds. Soft-ridged bench terrace made it possible to significantly reduce hazards arising from gravity erosion, and reduce the costs of individual bench construction and maintenance by 24.9% and 55.5% of the costs under traditional techniques, respectively. Such a construction allowed an enrichment and concentration of nutrients in the soils of terrace bunds, providing an ideal environment for a range of plants to grow and develop. The terrace riser could be planted with drought-resistant plants ranging from forage grasses to trees, and this riser vegetation would turn the exposed bunds and risers existing under traditional techniques into plant-covered belts, great green ribbons decorating farmland and contributing to the enhancement of the landscape biology. 1880 A preliminary study on vegetation-erosion dynamics and its applications Wang Z., Wang G., Li C. and Wang F. Science in China, Series D: Earth Sciences 2005 48/5 (689-700) Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the coupled differential equations for the vegetationerosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang watershed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation. Copyright by Science in China Press 2005. HYDROLOGY 1881 Using stable isotope tracers to assess hydrological flow paths, residence times and landscape influences in a nested mesoscale catchment Rodgers P., Soulsby C., Waldron S. and Tetzlaff D. Hydrology and Earth System Sciences 2005 9/3 (139-155) 18 O measurements in precipitation and stream waters were used to investigate hydrological flow paths and residence times at nested spatial scales in the mesoscale (233 km2 ) River Feugh catchment in the northeast of Scotland over the 2001-2002 hydrological year. Precipitation 18 O exhibited strong seasonal variation, which although significantly damped within the catchment, was reflected in stream water at six sampling sites. This 360 HYDROLOGY allowed 18 O variations to be used to infer the relative influence of soil-derived storm flows with a seasonally variable isotopic signature, and groundwater of apparently more constant isotopic composition. Periodic regression analysis was then used to examine the sub-catchment difference using an exponential flow model to provide indicative estimates of mean stream water residence times, which varied between approximately 3 and 14 months. This showed that the effects of increasing scale on estimated mean stream water residence time was minimal beyond that of the smallest (ca. 1 km2 ) headwater catchment scale. Instead, the interaction of catchment soil cover and topography appeared to be the dominant controlling influence. Where sub-catchments had extensive peat coverage, responsive hydrological pathways produced seasonally variable 18 O signatures in runoff with short mean residence times (ca. 3 months). In contrast, areas dominated by steeper slopes, more freely draining soils and larger groundwater storage in shallow valley-bottom aquifers, deeper flow paths allow for more effective mixing and damping of 18 O indicating longer residence times (> 12 months). These insights from 18 O measurements extend the hydrological understanding of the Feugh catchment gained from previous geochemical tracer studies, and demonstrate the utility of isotope tracers in investigating the interaction of hydrological processes and catchment characteristics at larger spatial scales. © 2005 Author(s). This work is licensed under a Creative Commons License. 1882 Discussion on hydrologic scaling (Chinese) Zhong Y., Jin C. and Pei T. Chinese Journal of Applied Ecology 2005 16/8 (1537-1540) Hydrologic scaling is the hotspot and frontier of today’s hydrologic research, which includes three different meanings distinguished from each other, i.e., process scale, observation scale and modelling scale. As a characteristic of hydrologic scale, dominant process scale has been paid more attention. Hydrologic scaling includes the scaling of hydrologic models, parameters, state variables and inputs, which owns special research methods respectively. The difficulty of hydrologic scaling mainly comes from the organized complexity of hydrologic systems, the heterogeneity and variability in space and time, and the insufficiency of data. The ubiquitous self-similarity of natural river networks makes itself an important part of hydrologic scaling research. The combination of various techniques and theories is needed to motivate hydrologic scaling research. Precipitation assessment 1883 Composition of wet and bulk deposition in Erzurum, Turkey Bayraktar H. and Turalioglu F.S. Chemosphere 2005 59/11 (1537-1546) Seasonal variations in the chemical characteristics of wet and bulk deposition samples collected in Erzurum were investigated for the period March 2002-January 2003. Major cations (Ca2+ , K+ , Mg 2+ ) and major anions (SO24 , NO 3 ) were determined in bulk and wet deposition samples; pH was also measured in wet deposition. The average pH of the wet deposition at Erzurum was 6.6 due to extensive neutralization of the acidity. A strong relationship between pH and SO24 concentrations was observed in all seasons; however, only a weak relationship was found between pH and NO-3 . On a seasonal basis, the correlation between Ca2+ and SO24 concentrations was stronger in winter than in summer. Seasonal variations of ions were examined in both wet and bulk deposition samples. Although maximum concentrations of anions generally occurred during winter and spring, cation concentrations peaked in summer for both wet and bulk deposition. Results indicated that Ca2+ was the dominant cation and SO24 the dominant anion in all deposition samples at Erzurum. Even though correlations among the crustal ions (calcium, magnesium and potassium) were high, the relationship between anthropogenic ions (sulfate and nitrate) was less clear in bulk deposition. © 2005 Elsevier Ltd. All rights reserved. 1884 Error characteristics of rainfall measurements by collocated Joss-Waldvogel disdrometers Tokay A., Bashor P.G. and Wolff K.R. Journal of Atmospheric and Oceanic Technology 2005 22/5 (513-527) Error characteristics of rainfall measurements were studied using six collocated Joss- Waldvogel (JW) disdrometers that are located at NASA’s Wallops Flight Facility. The six disdrometer means of rain rate R, reflectivity Z, and differential reflectivity ZDR, for a given minute were considered as a reference. The maximum deviations of R, Z, and ZDR from the mean in a rain event were 0.6 mm h-1 , 1.3 dB, and 0.05 dB, respectively. Rainfall statistics were then examined between disdrometer pairs. The root-mean-square (rms) difference of R, Z, and ZDR between paired disdrometers in a rain event were as high as 3.2 mm h-1 , 3.7 dB, and 0.3 dB, respectively. The rms difference of R and ZDR were even higher when the disdrometer observations were stratified based on reflectivity intervals. The differences in disdrometer rainfall measurements have a potential impact when the disdrometers are considered as calibration tools for vertically pointing and scanning radars. The differences between the disdrometer measurements also result in differences in coefficients and exponents of the derived relations between radar parameters and rain rate. Among the four different relations between radar parameters and rain rate, the absolute difference in rain rate R from two different JW disdrometers was highest in R(ZH, ZDR) and lowest in R(KDP, ZDR). The other two relations were R(Z) and R(KDP). The R increases with increasing horizontally polarized reflectivity ZH, and differential specific phase KDP in both single- and dual-parameter rainfall estimators, while the R increases with decreasing ZDR in dual-parameter rainfall estimators. Several sources of JW disdrometer malfunctions were also presented. The hardware problems were the leading cause for the malfunction of the JW disdrometers, as identified by the manufacturer. A single JW disdrometer could have inherent measurement errors that can only be identified in the presence of collocated (preferably two) rain-measuring instruments. © 2005 American Meteorological Society. 1885 Investigation of the rainfall variability in central Tunisia Kingumbi A., Bargaoui Z. and Hubert P. Hydrological Sciences Journal 2005 50/3 (493-508) The decrease in runoff of the Merguellil basin, Tunisia recorded during the decade 1989-1998 led to the study of several time series derived from daily rainfall. It was found that variability characteristics related to daily rainfall greater than 30 mm are significantly different among successive time periods. In addition, the probability distributions of these rains, recorded at different raingauge sites, are significantly different between the period 1976-1989 and the prior and posterior observation periods. Furthermore, the surface covered by daily rains greater than 30 mm decreased between 1976 and 1989. It was also noted that the probability distributions of the surfaces covered changed significantly after 1976. The combination of human action and pluviometric variability (rainfall increase in the period 1989-1998, notably the increase in the number of days of rainfall greater than 30 mm) may explain the decrease in runoff of Merguellil Wadi. Copyright © 2005 IAHS Press. 1886 Comparison of rain gauge observations with modeled precipitation over Cyprus using contiguous rain area analysis Tartaglione N., Mariani S., Accadia C. et al. Atmospheric Chemistry and Physics 2005 5/8 (2147-2154) Verification of modeled rainfall with precipitation observed by a rain gauge network has been performed in a case study over the Cyprus Island. Cyprus has a relatively dense rain gauge network. The applied verification method is the Contiguous Rain Area (CRA) analysis. Some drawbacks of the CRA method are pointed out when it is applied to such a case study. Impact on the CRA results, when considering different dimensions of the verification sub-domain and different types of indicators (correlation and mean square error) used in the comparison, are discussed. Results indicate that care should be taken when verification of modeled rainfall is performed over a domain smaller than the model one. © 2005 Author(s). This work is licensed under a Creative Commons License. HYDROLOGY 1887 A model for estimation of rain rate on tropical land from TRMM microwave imager radiometer observations Prabhakara C., Iacovazzi R., Yoo J.- M. and Kim K.- M. Journal of the Meteorological Society of Japan 2005 83/4 (595-609) Over the tropical land regions scatter plots of the rain rate (RPR ), deduced from the TRMM Precipitation Radar (PR) versus the observed 85 GHz brightness temperature (T85v ) made by the TRMM Microwave Imager (TMI) radiometer, for a period of a season over a given geographic region of 3°5° (lat Ion), indicate that there are two maxima in rain rate. One strong maximum occurs when T85v has a value of about 220 K, and the other weaker one when T85v is much colder 150 K. Also these two maxima are vividly revealed in plots of RPR vs. (T19v -T37v ). The strong maximum occurs when (T19v -T37v ) is 20 K and the weaker maximum when it is greater than 40 K. Together with the help of a) earlier investigations based on airborne Doppler Radar observations and b) radiative transfer theoretical simulations, we infer the strong maximum is a result of relatively weak scattering due to super cooled rain drops and water coated ice hydrometeors associated with a developing thunderstorm (Cb) that has a strong updraft. The other maximum is associated with strong scattering due to ice particles that are formed when the updraft collapses and the rain from the Cb is transitioning from convective type to stratiform type. Incorporating these ideas with a view to improve the estimation of rain rate from existing operational method applicable to the tropical land areas, we have developed a rain retrieval model. This model utilizes two parameters, that have a horizontal scale of 20 km, deduced from the TMI measurements at 10, 19, 21 and 37 GHz(T10v , T19v , T21v , T37v ). The third parameter in the model, namely the mean horizontal gradient <dT85v /dr> (K km-1 ) within the 20 km scale, is deduced from TMI measurements at 85 GHz that have the scale of 5 km. Utilizing these parameters our retrieval model is formulated to yield instantaneous rain rate on a scale of 20 km. This retrieval model is initially tuned with the help of a limited amount of PR rain rate. After initial tuning, the model is applied to widely different tropical land areas, and for different seasons. Our estimates of instantaneous rain rate, on a scale of 20 km, and seasonal averages on a scale of 3°5° (lat Ion) agree better with PR than that given by the operational TMI rain retrievals. © 2005, Meteorological Society of Japan. 1888 Accuracy verification of spaceborne radar estimates of rain rate Amitai E., Liao L., Llort X. and Meneghini R. Atmospheric Science Letters 2005 6/1 (2-6) The distribution of rain rate is of great concern for many hydrological applications. Probability distribution functions (pdf) of rain rate can now be obtained from spaceborne radar observations. Effort to evaluate these pdfs using ground observations is described. Copyright © 2005 Royal Meteorological Society. 1889 Semi-operational rainfall observations with X-band multi-parameter radar Maki M., Iwanami K., Misumi R. et al. Atmospheric Science Letters 2005 6/1 (12-18) Three-year semi-operational observations of rainfall distributions with NIED X-band multi-parameter (or polarimetric) radar started in the Kanto area of Japan from July 2003. The purposes and outlines of the radar observations with networks of rain gauges and disdrometers for ground validations are described. Preliminary results of validation analysis of polarimetric rain rate estimators show the usefulness of X-band multi-parameter radar for hydrological and meteorological applications in a small area. Copyright © 2005 Royal Meteorological Society. 1890 Combining radar and rain gauge rainfall estimates using conditional merging Sinclair S. and Pegram G. Atmospheric Science Letters 2005 6/1 (19-22) The Hydrologist’s traditional tool for measuring rainfall is the rain gauge. Rain gauges are relatively cheap, easy to maintain and provide a direct and suitably accurate estimate of rainfall at a point. What rain gauges fail to capture well is the spatial variability of rainfall with time, an important aspect for the credible modelling of a catchment’s response to rainfall. This spatial 361 variability is particularly evident at short timescales of up to several days. As the period of accumulation increases, the expected spatial variability is reduced and rain gauges provide improved spatial rainfall estimates. Because of the fractal variability of rainfall in space, simple interpolation between rain gauges does not provide an accurate estimate of the true spatial rainfall field, at short time scales. Weather radar provides (with a single instrument) a highly detailed representation of the spatial structure and temporal evolution of rainfall over a large area. Estimated rainfall rates are derived indirectly from measurements of reflectivity and are therefore subject to a combination of systematic and random errors. This article describes a recently proposed merging technique and presents an application to simulated rainfall fields. The technique employed is Conditional Merging (Ehret, 2002), which makes use of Kriging to extract the optimal information content from the observed data. A mean field based on the Kriged rain gauge data is adopted, while the spatial detail from the radar is retained, reducing bias, but keeping the spatial variability observed by the radar. The variance of the estimate is reduced in the vicinity of the gauges where they are able to provide good information on the true rainfall field. Copyright © 2005 Royal Meteorological Society. 1891 Rainfall modeling for integrating radar information into hydrological model Morin E., Goodrich D.C., Maddox R.A. et al. Atmospheric Science Letters 2005 6/1 (23-30) A spatial rainfall model was applied to radar data of air mass thunderstorms to yield a rainstorm representation as a set of convective rain cells. The modeled rainfall was used as input into hydrological model, instead of the standard radar-grid data. This approach allows a comprehensive linkage between runoff responses and rainfall structures. Copyright © 2005 Royal Meteorological Society. 1892 Radar rainfall estimation in the New Zealand context Gray W. and Larsen H. Atmospheric Science Letters 2005 6/1 (31-34) Difficulties commonly encountered in precipitation measurement by radar include errors from radar reflections from the surface, errors in extrapolating from measurements aloft, and errors through inadequately sampling a fluctuating signal. These error sources are discussed, along with the skill of the solutions that have been implemented. Copyright © 2005 Royal Meteorological Society. 1893 Nowcasting for New Zealand Gray W., Larsen H. and Seed A. Atmospheric Science Letters 2005 6/1 (35-39) Techniques are assessed for analysing the skill with which weather radar data can be extrapolated to provide short-term rainfall forecasts. In addition to visual inspection, forecast skill is assessed using catchment-averaged statistics - comparing analyses with rain gauge averages, forecasts with analyses and forecast river flow with measured flow. Copyright © 2005 Royal Meteorological Society. 1894 Assessing error in hydrological and hydraulic model output flows Robbins G.L. and Collier C.G. Atmospheric Science Letters 2005 6/1 (47-53) A hydraulic model of an urban drainage system with a Bayesian post processor is used to assess the uncertainty in model output flows associated with the use of measurements of rainfall made using raingauges, microwave link attenuation measurements and weather radar. Copyright © 2005 Royal Meteorological Society. 1895 Errors in surface rainfall rates retrieved from radar due to wind-drift Lack S.A. and Fox N.I. Atmospheric Science Letters 2005 6/1 (71-77) This article describes a series of experiments based on real data wherein the advection of the precipitation below the radar-sampled volume is estimated using Doppler radar determined wind fields. The experiments show that even at standard resolutions of 2 km the error can be extensive, and at higher resolutions and greater ranges (higher beam elevations) the errors become 362 HYDROLOGY very large. Errors are assessed using different Z-R relationships and resolutions as high as 0.5 km. Copyright © 2005 Royal Meteorological Society. 1896 Use of a stochastic precipitation nowcast scheme for fluvial flood forecasting and warning Pierce C., Bowler N., Seed A. et al. Atmospheric Science Letters 2005 6/1 (78-83) In collaboration with the Bureau of Meteorology (Melbourne, Australia), the Met Office (Joint Centre for Hydro-Meteorological Research, UK) has developed a stochastic precipitation nowcast scheme, designed to model and predict the PDF of surface rain rate and rain accumulation in space and time. Here we demonstrate the range of probabilistic products generated by the scheme, and their potential applications for fluvial flood forecasting and warning. With the aid of a hydrological model (the PDM), we consider the use of ensembles of predicted catchment rain accumulation in evaluating the range of possible river flow responses from a given catchment. When employed in conjunction with a catchment specific, cost-based decision-making model, we highlight the value of PDFs of forecast catchment rainfall accumulation and river flow as an aid to objective decision making within the flood warning process. © Crown Copyright 2005. Reproduced with the permission of Her Majesty’s Stationery Office. Published by John Wiley & Sons, Ltd. 1897 Virtual CSU-CHILL radar: The VCHILL Chandrasekar V., Cho Y.- G., Brunkow D. and Jayasumana A. Journal of Atmospheric and Oceanic Technology 2005 22/7 (979987) The Virtual CHILL (VCHILL) system makes it possible to transfer the educational and research experience of the Colorado State University dual polarization radar to remote locations over the Internet. The VCHILL operation includes remote control of radar and display of radar images, as well as the ability to locally process high-bandwidth radar data transferred over data networks. The low-bandwidth VCHILL operation allows the distant users to access the archived and real-time data estimated at the radar site and simultaneously display them on their local systems. A parallel receiver was developed exclusively for the high-bandwidth VCHILL. End-system architectures were designed to accommodate the demands of the high-bandwidth VCHILL operations in real time. A graphic user interface was also developed with the objective of easy installation and usage at various end-user institutions. The VCHILL not only expands the education experience provided by the radar system, but also stimulates the development of innovative research applications for atmospheric remote sensing. The VCHILL is being used by several universities for research and education. © 2005 American Meteorological Society. 1898 Regional rainfall frequency analysis for the state of Michigan Trefry C.M., Watkins Jr. D.W. and Johnson D. Journal of Hydrologic Engineering 2005 10/6 (437-449) Effective storm water management plans depend on reliable rainfall intensity-duration-frequency (IDF) relationships. Due to the perception of high-intensity rainfall events as occurring more frequently than expected, the Michigan Dept. of Transportation (MDOT) commissioned a study to update rainfall IDF estimates for each of seven durations (1, 2, 3, 6, 12, 18, and 24 h) and six recurrence intervals (2, 5, 10, 25, 50, and 100 years). In contrast to a traditional at-site frequency analysis using method of moments estimators, this study applied a regional frequency analysis approach based on L-moments. Data were compiled from 76 hourly recording stations and 152 daily recording stations, and trend and outlier analyses were conducted on both annual maximum series (AMS) and partial duration series (PDS) data. With the entire state considered a homogeneous region, two regional index flood models were applied: a generalized Pareto distribution fit to PDS data (PDS/GPA model), and a generalized extreme value distribution fit to AMS data (AMS/GEV model). Verification of results indicated that the revised rainfall IDF estimates provide more reliable values than those previously used. Journal of Hydrologic Engineering © ASCE. 1899 Short duration rainfall frequency analysis in Michigan using scale-invariance assumptions Gerold L.A. and Watkins Jr. D.W. Journal of Hydrologic Engineering 2005 10/6 (450-457) Intensity-duration-frequency (IDF) estimates are important statistical summaries of precipitation records used for hydrologic engineering design. To make use of recent data and modern statistical methods, the IDF estimates for the state of Michigan have been updated using a regional frequency analysis procedure. Since short duration data (less than one hour) are only available in the Detroit metropolitan area, scale-invariance assumptions are used to estimate short-duration IDF values throughout the state. Both simple scaling and multiscaling models are considered, and the simple scaling model is selected for practical purposes. Verification results indicate that the short-duration estimates are consistent with historical observations. Journal of Hydrologic Engineering © ASCE. 1900 Reconstructing solid precipitation from snow depth measurements and a land surface model Cherry J.E., Tremblay L.B., D´ery S.J. and Stieglitz M. Water Resources Research 2005 41/9 (1-15) [1] The amount and distribution of snowfall in the Arctic has significant effects on global climate. However, measurements of snowfall from gauges are strongly biased. A new method is described for reconstructing snowfall from observed snow depth records, meteorological observations, and running the NASA Seasonal-to-Interannual Prediction Project Catchment Land Surface Model (NSIPP CLSM) in an inverse mode. This method is developed and tested with observations from Reynolds Creek Experimental Watershed. Results show snowfall can be accurately reconstructed on the basis of how much snow must have fallen to produce the observed snow depth. The mean cumulative error (bias) of the reconstructed precipitation for 11 snow seasons is 29 mm snow water equivalent (SWE) for the corrected gauge measurement compared to -77 mm SWE for the precipitation from the corrected show gauges. This means the root-mean-square error of reconstructed solid precipitation is 30% less than that of gauge corrections. The intended application of this method is the pan-Arctic landmass, where estimates of snowfall are highly uncertain but where more than 60 years of historical snow depth and air temperature records exist. Copyright 2005 by the American Geophysical Union. 1901 Empirical mode decomposition in 2-D space and time: A tool for space-time rainfall analysis and nowcasting Sinclair S. and Pegram G.G.S. Hydrology and Earth System Sciences 2005 9/3 (127-137) A data-driven method for extracting temporally persistent information, at different spatial scales, from rainfall data (as measured by radar/ satellite) is described, which extends the Empirical Mode Decomposition (EMD) algorithm into two dimensions. The EMD technique is used here to decompose spatial rainfall data into a sequence of high through to low frequency components. This process is equivalent to the application of successive low-pass spatial filters, but based on the observed properties of the data rather than the predetermined basis functions used in traditional Fourier or Wavelet decompositions. It has been suggested in the literature that the lower frequency components (those with large spatial extent) of spatial rainfall data exhibit greater temporal persistence than the higher frequency ones. This idea is explored here in the context of Empirical Mode Decomposition. The paper focuses on the implementation and development of the two-dimensional extension to the EMD algorithm and it’s application to radar rainfall data, as well as examining temporal persistence in the data at different spatial scales. © 2005 Author(s). This work is licensed under a Creative Commons License. 1902 Archival precipitation data set for the Mississippi River Basin: Evaluation Nelson B.R., Krajewski W.F., Smith J.A. et al. Geophysical Research Letters 2005 32/18 (1-5) The goals of the Global Energy and Water Cycle Experiment Continental-Scale International Project (GCIP) point to the need fo high resolution data sets on all elements of the land surface and atmospheric hydrologic cycle. A high resolution precipitation HYDROLOGY data set has been derived from radar reflectivity observations taken from the National Weather Service WSR-88D radars in the continental U.S. To evaluate the product the authors provide several case studies of radar-rain gauge comparisons at locations throughout the Mississippi River Basin. They present bias, root mean square difference, fractional standard difference, and correlation coefficient statistics for radar-rain gauge comparisons for the hourly, daily, monthly, yearly and warm season temporal scale. These point (gauge) and pixel (radar) comparisons show large discrepancies at the hourly scale, on the order of 600-800%. An evaluation of the differences associated with temporally integrated estimates shows marked reduction in these discrepancies. At the long-term (warm season), these reduce to about 10%. An estimate of the difference in the comparison of the long term accumulation of gridded gauge based estimates and radar estimates at 0.25° 0.25° shows values in the range of 20% but decrease to about 15% after applying filtering techniques in the basin-wide comparisons. Copyright 2005 by the American Geophysical Union. Precipitation quality 1903 Trace metals in bulk precipitation and throughfall in a suburban area of Japan Hou H., Takamatsu T., Koshikawa M.K. and Hosomi M. Atmospheric Environment 2005 39/20 (3583-3595) Throughfall and bulk precipitation samples were collected monthly for 1.5 years over bare land and under canopies of Japanese cedar (Cryptomeria japonica), Japanese red pine (Pinus densiflora), Japanese cypress (Chamaecyparis obtusa), and bamboo-leafed oak (Quercus myrsinaefolia) in a suburban area of Japan. Samples were analyzed for dissolved Al, Mn, Fe, Cu, Zn, Ag, In, Sn, Sb and Bi by ICP-AES and ICP-MS. The metal concentrations were higher in throughfall, especially that of C. japonica, than bulk precipitation. Enrichment ratios (ERs: ratios of metal concentrations in throughfall to those in bulk precipitation) ranged from 2.5 (Zn) to 5.3 (Ag) (3.9 on average), and ERs for slightly soluble metals were generally higher than those for easily soluble metals. Concentrations of Mn, Fe, Cu, and Zn accounted for 99% of the total concentration of heavy metals in rainwater, whereas those of rare metals such as Ag, In, Sn, and Bi totaled <0.23%. Average concentrations of rare metals were 0.002 and 0.010 g l-1 for Ag, 0.001 and 0.005 g l -1 for In, 0.062 and 0.21 g l-1 for Sn, and 0.006 and 0.023 g l-1 for Bi in bulk precipitation and throughfall, respectively. The metal concentrations in rainwater were negatively correlated to the volume of rainwater, indicating that washout is the main mechanism that incorporates metals into rainwater. From the enrichment factors, that is, (X/Al)rain /(X/Al)crust , metals other than Fe were shown to be more enriched in rainwater than in the Earth’s crust, including those present as a result of leaching from soil dust (Mn) and from anthropogenic sources (Cu, Zn, Ag, In, Sn, Sb, and Bi). © 2005 Elsevier Ltd. All rights reserved. 1904 Enhanced dissolution of volatile organic compounds into urban dew water collected in Yokohama, Japan Okochi H., Kataniwa M., Sugimoto D. and Igawa M. Atmospheric Environment 2005 39/33 (6027-6036) Simultaneous sampling of six chlorinated hydrocarbons (CHs) and five monocyclic aromatic hydrocarbons (MAHs) in dew water and in the ambient air was performed from 1998 to 2000 in Yokohama, Japan. Dichloromethane (volume-weighted mean concentration (VWM): 2.43 nM) and trichloroethylene (VWM: 2.91 nM) were abundant among CHs in dew water, while toluene (VWM: 9.69 nM) and p-dichlorobenzene (VWM: 6.06 nM) were abundant among MAHs. The contribution of total measured volatile organic compounds (VOCs) concentration to dissolved organic carbon (DOC) concentration in dew water was only 0.02 wt% on average. The concentrations of VOCs except for dichloromethane and benzene in dew water were several hundred times higher than those in rainwater collected at the same site. In particular more hydrophobic VOCs with higher octanol-water partition coefficient KOW tended to be concentrated in dew water, indicating that urban dew water has stronger hydrophobicity than rainwater. Dew water contained higher amounts of VOCs 363 than would have been expected from the ambient gas-phase concentrations and Henry’s law constants. The enrichment factors, which were defined as the ratio of the observed concentration to the estimated, ranged from 6.98 (for dichloromethane) to 62.7 (for trichloroethylene) on average. Relatively high correlations (r>0.55) between the enrichment factors of highly hydrophobic VOCs (Kow >103 ) and the ratios of DOC to total inorganic ion concentration (TIC), which could be a potential surrogate of surface tension for urban dew water, indicated that the existence of any dissolved organic compounds, which could reduce the surface tension, in dew water also caused the enrichment of highly hydrophobic VOCs. © 2005 Elsevier Ltd. All rights reserved. 1905 Study of chemical composition in wet atmospheric precipitation in Eshidiya area, Jordan Al-Khashman O.A. Atmospheric Environment 2005 39/33 (61756183) The present study investigated the chemical composition of wet atmospheric precipitation samples in the Eshidiya area in south Jordan. The samples were analyzed from October 2003 to May 2004. All samples were analyzed for major ions (Cl- , NO3-, HCO3-, SO42-, Na+ , K+ , Ca 2+ , Mg2+ and NH4+) and trace metals (Cd, Cu, Pb, Zn, Fe and Ni). The highest concentration of elements is observed at the beginning of the rainfall season when large amounts of dust accumulate in the atmosphere scavenged by rain. The daily sample pH values ranged from 5.33 to 7.90 with a median value of 6.65 0.68. Rain water quality is characterized by low salinity and neutralized pH. High values of pH were attributed to the neutralization by natural alkaline local dusts which contain a large fraction of calcite and dolomite. The major ions in rainwater samples showed high Ca 2+ , HCO3-, SO42-, Cl- and Mg2+ concentrations. For trace metals, the study identified that the origin of these metals from local anthropogenic activities (from soil and phosphate mine, heating activities during the cold period of year (January to April) and the anthropogenic activities. In general, the results of this study suggest that the rainwater chemistry is strongly influenced by natural sources rather than anthropogenic and marine sources. © 2005 Elsevier Ltd. All rights reserved. 1906 A comparison of snow quality in two swedish municipalities-Lule and Sundsvall Reinosdotter K. and Viklander M. Water, Air, and Soil Pollution 2005 167/1-4 (3-16) In municipal planning of locations of snow deposits and investigations of the environmental effects of snow dumping, the partitioning of contaminants between particulate and dissolved matter is of great importance. This paper compares snow quality in two Swedish municipalities - Lule and Sundsvall over time. The two municipalities have differences in used de-icing material and winter conditions. Because Lule has a longer winter season and a lower average temperature, higher accumulations of chemicals were found in Lule than in Sundsvall. A multiple regression analysis indicated relationships between the dissolved fraction of heavy metals and the concentration of suspended solids and chloride. © Springer 2005. 1907 Fog- and rainwater chemistry in the tropical seasonal rain forest of Xishuangbanna, southwest China Wen J.L., Yi P.Z., Hong M.L. et al. Water, Air, and Soil Pollution 2005 167/1-4 (295-309) Fogwater, fog drip and rainwater chemistry were examined at a tropical seasonal rain forest in Xishuangbanna, southwest China between November 2001 and October 2002. During the period of observation, 204 days with the occurrence of radiation fog were observed and the total duration of fog was 1949 h, of which 1618 h occurred in the dry season (November to April), accounting for 37.0% of the time during the season. The mean pH of fogwater, fog drip and rainwater were 6.78, 7.30, and 6.13, respectively. The ion with the highest concentration for fog- and rainwater was HCO3 - , which amounted to 85.2 and 37.3 eq l-1 , followed by Ca2+ , Mg2+ and NH4 + . Concentrations of NO3 - , HCO3 - , NH4 + , Ca2+ , and K+ in fogwater samples collected in the dry season were significantly greater when compared to those collected in the rainy season. It was found that the ionic concentrations in fog drip were higher than those in fogwater, except for NH4 + and H+ , 364 HYDROLOGY which was attributed to the washout of the soil- and ash-oriented ions deposited on the leaves and the alkaline ionic emissions by the leaves, since biomass burns are very common in the region and nearby road was widening. © Springer 2005. 1908 Stable isotopes in precipitation recording South American summer monsoon and ENSO variability: Observations and model results Vuille M. and Werner M. Climate Dynamics 2005 25/4 (401-413) The South American Summer Monsoon (SASM) is a prominent feature of summertime climate over South America and has been identified in a number of paleoclimatic records from across the continent, including records based on stable isotopes. The relationship between the stable isotopic composition of precipitation and interannual variations in monsoon strength, however, has received little attention so far. Here we investigate how variations in the intensity of the SASM influence 18 O in precipitation based on both observational data and Atmospheric General Circulation Model (AGCM) simulations. An index of vertical wind shear over the SASM entrance (low level) and exit (upper level) region over the western equatorial Atlantic is used to define interannual variations in summer monsoon strength. This index is closely correlated with variations in deep convection over tropical and subtropical South America during the mature stage of the SASM. Observational data from the International Atomic Energy Agency-Global Network of Isotopes in Precipitation (IAEAGNIP) and from tropical ice cores show a significant negative association between 18 O and SASM strength over the Amazon basin, SE South America and the central Andes. The more depleted stable isotopic values during intense monsoon seasons are consistent with the so-called "amount effect", often observed in tropical regions. In many locations, however, our results indicate that the moisture transport history and the degree of rainout upstream may be more important factors explaining interannual variations in 18 O. In many locations the stable isotopic composition is closely related to El Ni˜no-Southern Oscillation (ENSO), even though the moisture source is located over the tropical Atlantic and precipitation is the result of the southward expansion and intensification of the SASM during austral summer. ENSO induces significant atmospheric circulation anomalies over tropical South America, which affect both SASM precipitation and 18 O variability. Therefore many regions show a weakened relationship between SASM and 18 O, once the SASM signal is decomposed into its ENSO-, and non-ENSO-related variance. © Springer-Verlag 2005. 1909 Review of precipitation monitoring studies in India A search for regional patterns Kulshrestha U.C., Granat L., Engardt M. and Rodhe H. Atmospheric Environment 2005 39/38 (7403-7419) This study is a review of rain chemistry measurements reported in India. Data from nearly 100 stations were reviewed with regard to sampling location, sampling method and chemical analyses. Some characteristic differences were found between the concentrations in different environments in line with known distributions of emissions. This was most clearly seen for SO4 2with median concentration increasing from rural and suburban to urban and industrial environments, with concentrations of HCO3 - and H+ varying the opposite way. Ca2+ concentration was higher in suburban and industrial environments compared to rural and urban. Concentration of NH+4 was lower in rural than in the other locations. Sea salt concentration (Na+ and Cl - in approximately constant proportion) was higher in urban than in rural locations at the same distance from the sea. The reported data from rural and suburban locations were used to derive large-scale concentration fields over India. With knowledge of emission fields and with the aid of output from a regional transport model it was possible to see some limited spatial resemblance between modelled and observed concentrations in cases of NH4 + , NO-3 and SO24 . For soil dust, current models are very crude but here some resemblance could be seen: primarily limited spatial resemblance with Ca2+ , pH and HCO-3 with generally increasing values towards NW. Four sites, at least two of them located in forested environments, had a mean rainwater pH close to neutral (concentration of H+ and HCO -3 about equal). Other sites had on average an excess of HCO-3 , becoming very substantial in the direction of the Thar Desert in NW India. With this review we conclude that there is a need to better assure the quality of the data with regard to sampling methods, chemical analyses and spatial representativeness. © 2005 Elsevier Ltd. All rights reserved. 1910 Chemical characterization of fog and rain water collected at the eastern Andes cordillera Beiderwieden E., Wrzesinsky T. and Klemm O. Hydrology and Earth System Sciences 2005 9/3 (185-191) During a three month period in 2003 and 2004, the chemistry of fog and rainwater were studied at the "El Tiro" site in a tropical mountain forest ecosystem in Ecuador, South America. The fogwater samples were collected using a passive fog collector, and for the rain water, a standard rain sampler was employed. For all samples, electric conductivity, pH, and the concentrations 2of NH+4 , K+ , Na+ , Ca2+ , Mg2+ , Cl- , NO-3 , PO34 , and SO4 were measured. For each fog sample, a 5 day back trajectory was calculated by the use of the HYSPLIT model. Two types of trajectories occurred. One type was characterized by advection of air masses from the East over the Amazonian basin, the other trajectory arrived one from the West after significant travel time over the Pacific Ocean. We found considerably higher ion concentrations in fogwater samples than in rain samples. Median pH values are 4.58 for fog water, and 5.26 for the rain samples, respectively. The median electric conductivity was 23 S cm-1 for the fog and 6 S cm-1 for the rain. The continent samples exhibit higher concentrations of most ions as compared to the pacific samples, but these differences could not be detected statistically. © 2005 Author(s). This work is licensed under a Creative Commons License. 1911 Precipitation scavenging of 7 Be and 137 Cs radionuclides in air Ioannidou A. and Papastefanou C. Journal of Environmental Radioactivity 2006 85/1 (121-136) Atmospheric depositional fluxes of the naturally occurring 7 Be of cosmogenic origin and 137 Cs from fallout of the Chernobyl accident were measured over a 6-year period (January 1987-December 1992) at Thessaloniki, Greece (40°38 N, 22°58 E). Total precipitation accumulation during 1987-1992 varied between 33.7 cm and 65.2 cm, reflecting a relatively dry (precipitationfree) climate. The activity concentrations of 7 Be and 137 Cs in rainwater depended on the precipitation rate, being higher for low precipitation rates and lesser for high precipitation rates. 137 Cs was removed by rain and snow more efficiently than 7 Be. Snowfall was more efficient than rainfall in removing the radionuclides from the atmosphere. The annual bulk depositional fluxes of 7 Be varied between 477 and 1133 Bq m-2 y-1 and this variability was attributed to the amount of precipitation and the variations of the atmospheric concentrations of 7 Be. The annual bulk depositional fluxes of 137 Cs showed a significant decrease over time from 1987 to 1992, resulting in a removal half-life of 1.33 years. The presence of 137 Cs in air, and therefore in rainwater and snow, long after the Chernobyl accident (26 April 1986) was mainly due to the resuspension process. The normalized depositional fluxes of both radionuclides showed maximal values during the spring season where the maximum amount of precipitation occurred. The relatively high positive correlation between 7 Be and 137 Cs normalized depositional fluxes indicates that the scavenging process of local precipitation controlled the fluxes of both radionuclides. The dry depositional flux of 7 Be was less than 9.37% of total (wet and dry) depositional flux. The fraction of dry-to-total depositional flux of 137 Cs was much higher than that of 7 Be, due to the resuspended soil. © 2005 Elsevier Ltd. All rights reserved. Interception, throughfall and stemflow 1912 Retention and translocation of foliar applied 239,240 Pu and 241 Am, as compared to 137 Cs and 85 Sr, into bean plants (Phaseolus vulgaris) Henner P., Colle C. and Morello M. Journal of Environmental Radioactivity 2005 83/2 (213-229) HYDROLOGY 241 Am, 239,240 Pu, 137 Cs 85 Sr and was evaluated Foliar transfer of after contamination of bean plants (Phaseolus vulgaris) at the flowering development stage, by soaking their first two trifoliate leaves into contaminated solutions. Initial retentions of 241 Am (27%) and 239,240 Pu (37%) were higher than those of 137 Cs and 85 Sr (10-15%). Mean fraction of retained activity redistributed among bean organs was higher for 137 Cs (20.3%) than for 239,240 Pu (2.2%), 241 Am (1%) or 85 Sr (0.1%). Mean leafto-pod translocation factors (Bq kg-1 dry weight pod/Bq kg-1 dry weight contaminated leaves) were 5.0 10 -4 for 241 Am, 2.7 10-6 for 239,240 Pu, 5.4 10-2 for 137 Cs and 3.6 10-4 for 85 Sr. Caesium was mainly recovered in pods (12.8%). Americium and strontium were uniformly redistributed among leaves, stems and pods. Plutonium showed preferential redistribution in oldest bean organs, leaves and stems, and very little redistribution in forming pods. Results for americium and plutonium were compared to those of strontium and caesium to evaluate the consistency of the attribution of behaviour of strontium to transuranium elements towards foliar transfer, based on translocation factors, as stated in two radioecological models, ECOSYS-87 and ASTRAL. © 2005 Elsevier Ltd. All rights reserved. 1913 Liquid and chemical fluxes in precipitation, throughfall and stemflow: Observations from a deciduous forest and a red pine plantation in the midwestern U.S.A. Pryor S.C. and Barthelmie R.J. Water, Air, and Soil Pollution 2005 163/1-4 (203-227) Wet deposition (WD), throughfall (TF) and stemflow (SF) measurements undertaken in a deciduous forest show 85% of the WD liquid flux is observed as TF and approximately 2% as SF. TF and SF were observed to be enriched in base cations and accordingly had an average pH of 6.1 and 5.9, respectively relative to a WD pH of 5.1. The seasonal variability of TF pH below the deciduous canopies was more pronounced than that of WD though both exhibited a growing season maximum, and there is evidence that the seasonal variability of TF pH below the pines is inverted relative to the deciduous canopies likely due to enhanced dust capture and buffering by calcium carbonate. TF ion concentrations differed significantly between deciduous and pine canopies during the growing season, and there is some evidence that variation in sky view factor of 0.18-0.22 is sufficient to manifest statistically differing TF composition below sugar maples. The total atmospheric flux of inorganic nitrogen to the forest is approximately 14-18 kg-N ha-1 yr-1 with approximately half taken up by the canopy. Associated experiments designed to quantify uncertainties in the nutrient fluxes included laboratory tests of the Aerochem automated wet-dry sampler. These experiments indicate the delay in initiating sample collection is less than half a minute for rainfall rates above 1 cm h-1 , but may increase substantially for lower precipitation rates. © Springer 2005. 1914 Rainfall interception model of forest canopy: A preliminary study (Chinese) Guo M., Yu P., Wang Y. et al. Chinese Journal of Applied Ecology 2005 16/9 (1633-1637) Canopy interception is an important hydrological process in forest ecosystem, and its modelling is of significance to understand and estimate the rainfall interception by the canopy. In this paper, a canopy rainfall interception model was established by dividing a rain incident into a set of short period, calculating the rainfall distribution intercepted by the canopy, and educing the process of the rain incident. This model considered the effects of the dryness of canopy and trunk on the evaporation from wet canopy and trunk during one rain incident, and introduced two factors, leaf area index (LAI) and surface area of trunk per unit area of ground (SAI), when computing the evaporation. The application of the model to simulate the rainfall interception process in a Larix principis-rupprechtii plantation in Guyuan, south Ningxia Hui autonomous region of China showed that the simulated and measured throughfall were identical, and the absolute deviation between simulated and measured results was within 1 mm. But, when the precipitation was smaller than 6 mm, the simulated throughfall was lower than the measured one. The values of simulated stemflow were lower than the measured values, and the relative deviation between simulated and measured values was smaller when the precipitation was larger. The process of 365 throughfall in the forest was also simulated, with the results fitted well to the measured one. Evaporation and transpiration 1915 Evaporation and land surface energy budget at the Salar de Atacama, Northern Chile Kampf S.K., Tyler S.W., Ortiz C.A. et al. Journal of Hydrology 2005 310/1-4 (236-252) Playa systems are driven by evaporation processes, yet the mechanisms by which evaporation occurs through playa salt crusts are still poorly understood. In this study we examine playa evaporation as it relates to land surface energy fluxes, salt crust characteristics, groundwater and climate at the Salar de Atacama, a 3000 km2 playa in northern Chile containing a uniquely broad range of salt crust types. Land surface energy budget measurements were taken at eight representative sites on this playa during winter (August 2001) and summer (January 2002) seasons. Measured values of net all-wave radiation were highest at vegetated and rough halite crust sites and lowest over smooth, highly reflective salt crusts. Over most of the Salar de Atacama, net radiation was dissipated by means of soil and sensible heat fluxes. Dry salt crusts tended to heat and cool very quickly, whereas soil heating and cooling occurred more gradually at wetter vegetated sites. Sensible heating was strongly linked to wind patterns, with highest sensible heat fluxes occurring on summer days with strong afternoon winds. Very little energy available at the land surface was used to evaporate water. Eddy covariance measurements could only constrain evaporation rates to within 0.1 mm d-1 , and some measured evaporation rates were less than this margin of uncertainty. Evaporation rates ranged from 0.1 to 1.1 mm d-1 in smooth salt crusts around the margin of the salar and from 0.4 to 2.8 mm d-1 in vegetated areas. No evaporation was detected from the rugged halite salt crust that covers the interior of the salar, though the depth to groundwater is less than 1 m in this area. These crusts therefore represent a previously unrecorded end member condition in which the salt crusts form a practically impermeable barrier to evaporation. © 2005 Elsevier B.V. All rights reserved. 1916 Effects of vapor-pressure deficit and net-irradiance calculation methods on accuracy of standardized PenmanMonteith equation in a Humid climate Yoder R.E., Odhiambo L.O. and Wright W.C. Journal of Irrigation and Drainage Engineering 2005 131/3 (228-237) The effects of some common vapor pressure deficit (VPD) and net irradiance (Rn ) calculation methods on the accuracy of ETo values estimated by using the standardized ASCE Penman-Monteith (ASCE-PM) equation for short grass were examined by comparing the estimated ETo values with measured ETo , values in a humid climate. Sensitivity analysis showed 17% and 84% change in the estimated daily ETo values per unit change in the calculated VPD and Rn values, respectively. A total of 12 VPD and 27 Rn calculation methods were examined. Analyses of variance indicated lack of equality in the means of estimated ETo values obtained by different VPD and Rn methods. The percent mean error in the estimated ETo values ranged from -0.9 to -8.4% for VPD methods and from -0.3 to -19.7% for Rn methods. On the basis of the coefficient of determination (r2 ) and the standard error of the estimated (Sy/x ) values, the VPD calculated from saturation vapor pressure (es ), estimated by averaging the es at the maximum and minimum daily air temperatures, and actual vapor pressure (ea ), estimated by using either the average of minimum and maximum relative humidity or the dew-point temperature, gave more accurate results. Net irradiance (Rn ) estimated by using a regression of relative short-wave solar irradiance, as well as a linear regression on the square root of ea , resulted in relatively more accurate estimates of ETo , than that obtained by methods based on ea or clear-sky data alone. These results indicate that in a humid climate, some of the VPD and Rn methods have a significant effect on the accuracy of the ETo estimated by using the standardized ASCE-PM equation. Journal of Irrigation and Drainage Engineering © ASCE. 366 HYDROLOGY 1917 Sensitivity of the food and agriculture organization Penman-Monteith evapotranspiration estimates to alternative procedures for estimation of parameters Nandagiri L. and Kovoor G.M. Journal of Irrigation and Drainage Engineering 2005 131/3 (238-248) Reference crop evapotranspiration (ETo ) is a key variable in procedures established for estimating evapotranspiration rates of agriculture crops. As per internationally accepted procedures outlined in the United Nations Food and Agriculture Organization’s Irrigation and Drainage Paper No. 56 (FAO-56), using the Penman-Monteith (PM) combination equation is the recommended approach to computing ETo from ground-based climatological observations. Applying of the PM equation requires converting input climate and site data into a number of parameters, and FAO-56 recommends exact procedures for estimating these parameters. However, a plethora of alternative procedures for estimating parameters exist in literature. As a consequence, it is likely that ambiguous results may be obtained from the FAO-56 PM equation because of the adoption of such alternative (nonrecommended) supporting equations. The purpose of the present study is to evaluate differences that could arise in FAO-56 ETo estimates if nonrecommended equations are used to compute the parameters. Using historical climate records from 1973 to 1992 of a station located in the humid tropical region of Karnataka State, India, monthly ETo , estimates computed by FAO-56 recommended procedures were statistically compared with those obtained by introducing alternative procedures for estimating parameters. In all, 13 alternative algorithms for ETo estimation were formulated, involving modified procedures for parameters associated with weighting factors, net radiation, and vapor-pressure-deficit terms of the PM equation. For the 240-month period considered, nine of these algorithms yielded ETo estimates that were in close correspondence with FAO-56 estimates as indicated by mean absolute relative difference (AMEAN) values within 1% and maximum absolute relative difference (MAXE) values within 2%. The remaining four algorithms, involving nonrecommended procedures for the vapor-pressure-deficit and net-radiation parameters, yielded considerably different ETo estimates, giving rise to AMEAN values in the range of 2 to 8% and MAXE values ranging between 8 and 28%. The results of this study highlight the need for strict adherence to recommended procedures, especially for estimating of vapor-pressure-deficit and net-radiation parameters if consistent results are to be obtained by the FAO56 approach. Journal of Irrigation and Drainage Engineering © ASCE. 1918 Simplified estimation of reference evapotranspiration from pan evaporation data in California Snyder R.L., Orang M., Matyac S. and Grismer M.E. Journal of Irrigation and Drainage Engineering 2005 131/3 (249-253) Evaporation pan (Ep ) data are often used to estimate reference evapotranspiration (ETo ) for use in water resource planning and irrigation scheduling. This paper reviews equations to estimate ETo from Ep and provides a simpler method to make this conversion for arid climatic conditions like in California. The new method accounts for fetch differences by first adjusting the EP rates to values expected for 100 m of grass fetch. Then it relies on an empirical relationship between ETo and the adjusted Ep to determine Kp values; thus, eliminating the need for relative humidity and wind speed data that are often unavailable. The method is conceptually simpler, easier to code into computer applications, and within California, it gave better results than methods based on relative humidity and wind speed. However, the method might require calibration in more humid or windier climates. Journal of Irrigation and Drainage Engineering © ASCE. 1919 Data reconciliation on the complex hydraulic system of Canal de Provence Deltour J.- L., Canivet E., Sanfilippo F. and Sau J. Journal of Irrigation and Drainage Engineering 2005 131/3 (291-297) A data reconciliation module, based on the measurements from the hydraulic network, has been recently developed and implemented in the supervisory system of the Soci´et´e du Canal de Provence (SCP). The software has initially been used daily to check the measured flow on the main canal. The data reconciliation occurs just after the measurement process. The measurement network on the hydraulic system includes many sensors subject to failure or deviation and is spread over a huge area. In addition, discharge and volume measurements in open-channel hydraulic networks are characterized by large uncertainties. The objective of the data reconciliation is to take advantage of information redundancy on a system to make a cross-check of real-time measurements. By using this information redundancy, a data reconciliation module allows detection of inconsistent measurements and measurement deviations and provides corrected values whether the initial measurements are valid, biased, or invalid. A derived consequence is better scheduling of the maintenance of sensors. The results are corrected values for measured variables and proposed values for nonmeasured quantities. A statistical analysis of the results is performed. This analysis allows evaluation of the uncertainties attached to the estimated flows and volume values. It allows also detecting invalid measurements and drift of sensors and making decisions about which maintenance operations to perform. Journal of Irrigation and Drainage Engineering © ASCE. 1920 An approach to estimating evapotranspiration in the Urumqi River basin, Tianshan, China, by means of remote sensing and a geographical information system technique Zhang W., Chen J., Ogawa K. and Yamaguchi Y. Hydrological Processes 2005 19/9 (1839-1854) An approach that makes use of meteorological measurements and the spatial perspective provided by satellite data to estimate the time series (monthly or daily) of evapotranspiration (ET) over heterogeneous terrain two-dimensionally has been developed and tested in the Urumqi River basin, Tianshan, China. The formulae utilized in the estimation of actual ET are based on Kojima’s equation for a glacier/snow-covered area and Morton’s complementary relationship for the other land-cover classes. Data integration and image processing for the estimated ET were all executed on a raster image file that combines Landsat TM (red and NIR reflectance data), land-cover classification and digital elevation model (DEM) in association with the use of meteorological data under a geographic information system (GIS) environment. The specific type of model (either Kojima’s or Morton’s) and the extent to which it should be applied are determined jointly by the land-cover categories and an algorithm describing the seasonal land-cover changes. The spatially distributed meteorological parameters driving the model were either interpolated from the routine observations with PRISM in the sparse network of meteorological stations or calculated by the relationships of these parameters with those routinely observed. Ground-surface albedo data were derived by two approaches. For the season when the TM scene was acquired it was obtained by weighting the Landsat TM red and NIR reflectance data. For the other seasons, when the TM scene is not available, it was approximated by multiplying the empirical parameters in regard to each land-cover category with the albedo map of the season when the TM scene was available. As a result, time series of ET can be obtained not only quantitatively, but also visually as a two-dimensional image map. The approach proposed was applied to the Urumqi River basin, China. With field lysimeter data and estimates by the water balance method and the converted results from pan measurements as standard, a method validation was conducted and the accuracy of ET estimation by the approach was evaluated. Copyright © 2005 John Wiley & Sons, Ltd. 1921 Evapotranspiration from a riparian fen wetland Andersen H.E., Hansen S. and Jensen H.E. Nordic Hydrology 2005 36/2 (121-135) Evapotranspiration rates were measured in a riparian fen wetland dominated by vascular vegetation and surrounded by open agricultural areas and forests. The wetland is situated on a floodplain in central Denmark. Measurements were taken throughout the growing season (April-September) of 1999. Evapotranspiration rates were higher than th ose published for other wetland types, with an average of 3.6 mm d-1 during the growing season and a peak rate of 5.6 mm d-1 . Daily average evapotranspiration was 110% of Penman’s potential open water evaporation. Evatranspiration was the dominant sink in the energy balance of the wetland studied. During the day, evapotranspiration accounted for 82% of the available radiant energy, Rn . Due to the presence of deposited fine-grained sediments, soil-water availability was HYDROLOGY kept high at all times which resulted in moderate canopy resistances, rc . (overall mean = 32 sm-1 ). Evapotranspiration was controlled by a combination of driving forces: Rm saturation vapour pressure deficit, D, and rc . It is hypothesized that the results presented in this study are conditioned by the proximity of the wetland to drier upland areas. During periods with high evaporative demand and low precipitation, warm, dry air is formed over the upland areas and wetland evapotranspiration rates are enhanced by local advection. Indicative evidence for the hypothesis is presented. Although the absolute magnitude of the results reported is only directly relevant to similar sites in Denmark, the processes and controls described are considered to be representative of riparian wetlands subjected to frequent flooding and/or with a high groundwater table, with vascular vegetation, and which are narrow corridors in open agricultural landscapes. © IWA Publishing 2005. 1922 Dynamics of transpiration and evaporation following a moisture pulse in semiarid grassland: A chamber-based isotope method for partitioning flux components Yepez E.A., Huxman T.E., Ignace D.D. et al. Agricultural and Forest Meteorology 2005 132/3-4 (359-376) We describe a novel method for partitioning evapotranspiration (ET) from isotopic measurements of water vapor within large (4.86 m3 ) plot-scale gas exchange chambers. Using this approach, the short-term (15-day) dynamics of transpiration (T) and evaporation (E) in experimental replicated stands of the invasive grass Eragrostis lehmanniana and the native Heteropogon contortus were assessed following a 39-mm irrigation event in semiarid grassland in southeastern Arizona, USA. Water vapor samples (20-40 L each) were collected sequentially during a 6min transient increase of vapor concentration inside the chambers and used to produce Keeling plots (isotope mixing relationships) for identification of the isotopic composition of ET and partitioning of component fluxes. The method worked well in plots free of grass cover and in the sparsely covered plots of E. lehmanniana. Keeling plot estimates of the isotopic composition of soil evaporation ( E ) in bare plots closely matched modeled values, lending strong support for the validity of the chamber approach. T/ET increased in stands of E. lehmanniana from 0.35 0.07 on day 1 to 0.43 0.08 on day 3 after the irrigation pulse, but decreased to 0.22 0.05 by day 7 as the soil surface dried. Estimates of stand transpiration from the Keeling plot chamber method were positively correlated (Pearson’s r = 0.76, p = 0.0004, n = 17) with independent estimates based on leafto-canopy scaling of stomatal conductance. We were unable to calculate T/ET on days 1 and 3 in plots of H. contortus because Keeling plot intercepts did not fall within the range of soil and canopy end-member isotope values. This likely occurred due to unaccounted effects of a wet litter layer on the estimation of E . Our approach is useful for partitioning ET over a dynamic wetting event in semi-arid grassland at a scale relevant for experimental ecosystem studies, but requires further validation under a wide range of vegetation structures and environmental conditions. © 2005 Elsevier B.V. All rights reserved. 1923 Comparative analysis of the actual evapotranspiration of Flemish forest and cropland, using the soil water balance model WAVE Verstraeten W.W., Muys B., Feyen J. et al. Hydrology and Earth System Sciences 2005 9/3 (225-241) This paper focuses on the quantification of the green - vegetation related - water flux of forest stands in the temperate lowland of Flanders. The underlying reason of the research was to develop a methodology for assessing the impact of forests on the hydrologic cycle in comparison to agriculture. The tested approach for calculating the water use by forests was based on the application of the soil water balance model WAVE. The study involved the collection of data from 14 forest stands, the calibration and validation of the WAVE model, and the comparison of the water use (WU) components - transpiration, soil and interception evaporation - between forest and cropland. For model calib ration purposes simulated and measured time series of soil water content at different soil depths, period March 2000-August 2001, were compared. A multiplesite validation was conducted as well. Actual tree transpiration calculated with sap flow measurements in three forest stands gave similar results for two of the three 367 stands of pine (Pinus sylvestris L.), but WAVE overestimated the actual measured transpiration for a stand of poplar (Populus sp.). A useful approach to compare the WU components of forest versus cropland is scenario analysis based on the validated WAVE model. The statistical Profile Analysis method was implemented to explore and analyse the simulated WU time series. With an average annual rainfall of 819 mm, the results reveal that forests in Flanders consume more water than agricultural crops. A 30 years average of 491 mm for 10 forests stands versus 398 mm for 10 cropped agricultural fields was derived. The WU components, on yearly basis, also differ between the two land use types (transpiration: 315 mm for forest and 261 mm for agricultural land use; soil evaporation: 47 mm and 131 mm, for forest and cropland, respectively). Forest canopy interception evaporation was estimated at 126 mm, while it was negligible for cropland. © 2005 Author(s). This work is licensed under a Creative Commons License. 1924 Evapotranspiration of natural Quercus liaotungensis and Tilia paucicostata secondary stands in Liupan Mountains of Ningxia (Chinese) Xiong W., Wang Y., Yu P. et al. Chinese Journal of Applied Ecology 2005 16/9 (1628-1632) With heat dissipation probe technique and combined with microlysimeter and hydrological methods, this paper studied the evapotranspiration of secondary Quercus liaotungensis and Tilia paucicostata stands, and its relationship to forest structure from August to September 2004. The results indicated that the stem sap flux density (SFD) Of Quercus liaotungensis and Tilia paucicostata changed regularly from day to night in later growth season. In relatively still period (nighttime), the SFD kept low values continuously, usually below 0.05 lcm-2 min-1 , while in active period (daytime), it increased quickly, usually below 0.25 lcm-2 . min-1 . The daily transpiration of whole-tree was estimated based on the calculation of daily cumulative SFD, which showed that there existed a significant difference between two tree species. The daily transpiration of Quercus liaotungensis reached 5.31 and 2.48 Ld-1 in sunny- and cloudy-days, 2.35 and 3.75 folds as that of Tilia paucicostata, respectively. There was no significant difference in daily leaf transpiration rate between these two shrub species. During measurement periods, the average daily stand evapotranspiration was 1.45 mmd-1 , including transpiration (0.72 mmd-1 ), soil evaporation (0.19 mmd-1 ), and canopy interception (0.54 mmd-1 ), which accounted for 49.6%, 13.3% and 37.1% of the total evapotranspiration, respectively. The results showed that the difference of whole-tree transpiration between tree species contributed significantly to the difference of tree canopy transpiration, while the difference of shrub canopy transpiration was on account of the leaf amount in the canopy. The effects of vertical layers in the stand on total stand evapotranspiration also differed, with a percentage of 65.8%, 20.9% and 13.3% for tree canopy, shrub canopy and floor, respectively, which meant that the transpiration and interception of tree canopy contributed most to the total evpotranspiration, followed by shrub transpiration, soil evaporation, and grass transpiration. Runoff, streamflow and basins 1925 A method for evaluating the accuracy of quantitative precipitation estimates from a hydrologic modeling perspective Gourley J.J. and Vieux B.E. Journal of Hydrometeorology 2005 6/2 (115-133) A major goal in quantitative precipitation estimation and forecasting is the ability to provide accurate initial conditions for the purposes of hydrologic modeling. The accuracy of a streamflow prediction system is dependent upon how well the initial hydrometeorological states are characterized. A methodology is developed to objectively and quantitatively evaluate the skill of several different precipitation algorithms at the scale of application-a watershed. Thousands of hydrologic simulations are performed in an ensemble fashion, enabling an exploration of the model parameter space. Probabilistic statistics are then utilized to compare the relative skill of hydrologic simulations produced 368 HYDROLOGY from the different precipitation inputs to the observed streamflow. The primary focus of this study is to demonstrate a methodology to evaluate precipitation algorithms that can be used to supplement traditional radar-rain gauge analyses. This approach is appropriate for the evaluation of precipitation estimates or forecasts that are intended to serve as inputs to hydrologic models. © 2005 American Meteorological Society. 1926 A recent increase in western U.S. Streamflow variability and persistence Pagano T. and Garen D. Journal of Hydrometeorology 2005 6/2 (173-179) April-September streamflow volume data from 141 unregulated basins in the western United States were analyzed for trends in year-to-year variability and persistence. Decadal time-scale changes in streamflow variability and lag-1-yr autocorrelation (persistence) were observed. The significance of the variability trends was tested using a jackknife procedure involving the random resampling of seasonal flows from the historical record. The 1930s-50s was a period of low variability and high persistence, the 1950s-70s was a period of low variability and antipersistence, and the period after 1980 was highly variable and highly persistent. In particular, regions from California and Nevada to southern Idaho, Utah, and Colorado have recently experienced an unprecedented sequence of consecutive wet years along with multiyear extreme droughts. 1927 Comparative analysis of glacial and nival streamflow regimes with implications for lotic habitat quantity and fish species richness Fleming S.W. River Research and Applications 2005 21/4 (363379) Growing interest in the differential responses of glacial and nival rivers to climatic forcing, and in ecological distinctions between the two streamflow regimes, suggests the need for a better comparative understanding of how the annual hydrologic cycle differs with presence or absence of catchment glacial cover. In this study, timing and magnitude characteristics of the average annual hydrographs of five glacierized and four nival catchments in the southwestern Canadian subarctic are empirically identified and compared. Likely effects upon fish habitat are qualitatively assessed, and net fisheries potential is tentatively investigated using taxa richness data. The chief hydrological conclusions at P < 0.05 using Kolmogorov-Smirnov and empirical orthogonal function analyses are: (1) catchment glacial cover results in freshets that are longer, larger, and peak later than those experienced by the nival regime; (2) the winter baseflows of glacial rivers are also much higher on a unit-catchment-area basis; and (3) basin scale and degree of catchment glacial cover are of comparable importance in determining the magnitude of the annual hydrologic cycle. These differences arise from the greater availability, both in volume and over time, of meltwater in glacial catchments, which in part reflects the consistently negative alpine glacial mass balances observed both in the present study area and globally under historical climatic warming. Such regime distinctions result in increased spawning season and winter aquatic habitat availability, which may in turn offset negative habitat characteristics previously identified for glacial river ecosystems. While previous studies have suggested that glacial influences tend to decrease macroinvertebrate diversity and increase salmon populations, preliminary analysis of available fish species presence/absence data from the current study area tentatively appears to suggest similar or, perhaps, slightly higher fish taxa richness relative to nival streams; in all three cases, however, catchment lake cover may play a key hydroecological modifying role. The results strongly confirm and extend existing understanding of glacial-nival regime differences with respect to both streamflow and fisheries ecology, and raise new questions for future research. Copyright © 2005 John Wiley & Sons, Ltd. 1928 Assessing the effectiveness of enhancement activities in urban streams: I. Habitat responses Suren A.M., Riis T., Biggs B.J.F. et al. River Research and Applications 2005 21/4 (381-401) Effects of stream enhancement on habitat conditions in five spring-fed urban streams in Christchurch, New Zealand, were investigated. Stream enhancement consisted of riparian planting at three sites, and riparian planting and channel modifications at two sites, where a concrete dish channel and a timber-lined channel were removed, and natural banks reinstated. Sites were surveyed prior to enhancement activities and 5 years after, and changes in riparian conditions (composition, horizontal and vertical cover), instream conditions (bank modifications, inorganic and organic material on the streambed), and hydraulic conditions (wetted perimeter, cross-sectional area, depths and velocities) quantified. Enhanced sites generally had higher marginal vegetation cover, as well as increased overhanging riparian vegetation, reflecting planting of Carex sedges close to the water. Bed sediments changed at some sites, with the greatest change being replacement of a concrete channel with gravel and cobble substrate. Bryophyte cover declined at this site, reflecting loss of stable habitat where these plants grew. Bed sediments changed less at other sites, and cover of fine sediments increased in some enhanced sites, presumably from sediment runoff from nearby residential development. Filamentous algal cover decreased at one stream where shade increased, but increased in another stream where the removal of timber-lined banks and creation of a large pond decreased shade. Stream enhancement increased variability in velocity at three of the five sites, but overall changes to stream hydraulics were small. Although enhancement activities altered the physical conditions of the streams, major changes occurred only to riparian vegetation and bank conditions. Lack of other major changes to instream physical conditions most likely reflected the limited range of channel morphology alterations under-taken. Moreover, the flat topography of Christchurch and naturally low stream discharge further constrained changes to instream physical conditions from enhancement activities. Sediment inputs from continuing urban development also negated the effects of adding coarse substrates. These over-arching factors may constrain the success of future stream enhancement projects within Christchurch. Copyright © 2005 John Wiley & Sons, Ltd. 1929 Assessing the effectiveness of enhancement activities in urban streams: II. Responses of invertebrate communities Suren A.M. and McMurtrie S. River Research and Applications 2005 21/4 (439-453) The effects of habitat enhancement on the invertebrate communities in five urban streams in Christchurch, New Zealand, were investigated. All streams underwent riparian planting, while extensive channel modifications were made at two streams, where a concrete dish channel and a wooden timber-lined stream were removed and natural banks reinstated. Benthic invertebrates were collected before enhancement and 5 years after from the same locations. Invertebrates were also collected from control sites in each stream in 2001. Desired goals of enhancement activities included increasing the densities of mayflies and caddisflies, and decreasing densities of oligochaetes, snails and midges. Enhancement activities changed riparian vegetation and bank conditions, as well as substrate composition, instream organic matter and variability of instream velocities. Invertebrate communities prior to enhancement were typical of those in urban environments, and dominated by snails (Potamopyrgus, Physa), the amphipod Paracalliope, the hydroptilid caddisfly Oxyethira, oligochaetes and chironomids. Stream enhancement caused only small changes to the invertebrate community, with subtle shifts in overall abundance, species evenness, diversity, and ordination scores. Lack of a consistent strong response by invertebrates to enhancement activities, and continued absence of caddisflies and mayflies from enhanced sites may reflect lack of sufficient change to instream conditions as a result of stream enhancement, colonization bottlenecks for aerial stages of these animals, and the inability of individuals outside the urban watershed to perceive these enhanced ‘islands’ of good habitat. Alternatively, contamination of streambed sediments, excess sedimentation and reduced base flows may be limiting factors precluding successful invertebrate colonization in enhanced sites. These results highlight the importance of setting clear goals and objectives necessary to meet these goals. Enhancement of riparian zones in urban streams may not be adequate to improve benthic invertebrate communities. Identifying over-arching factors that potentially limit invertebrate communities will enable the enhancement potential of streams to be better assesed, and allow managers to identify sites where recovery of biological communities is pos- HYDROLOGY sible, and where such recovery is not. Copyright © 2005 John Wiley & Sons, Ltd. 1930 Changes toward earlier streamflow timing across western North America Stewart I.T., Cayan D.R. and Dettinger M.D. Journal of Climate 2005 18/8 (1136-1155) The highly variable timing of streamflow in snowmelt-dominated basins across western North America is an important consequence, and indicator, of climate fluctuations. Changes in the timing of snowmelt-derived streamflow from 1948 to 2002 were investigated in a network of 302 western North America gauges by examining the center of mass for flow, spring pulse onset dates, and seasonal fractional flows through trend and principal component analyses. Statistical analysis of the streamflow timing measures with Pacific climate indicators identified local and key large-scale processes that govern the regionally coherent parts of the changes and their relative importance. Widespread and regionally coherent trends toward earlier onsets of springtime snowmelt and streamflow have taken place across most of western North America, affecting an area that is much larger than previously recognized. These timing changes have resulted in increasing fractions of annual flow occurring earlier in the water year by 1-4 weeks. The immediate (or proximal) forcings for the spatially coherent parts of the year-to-year fluctuations and longer-term trends of streamflow timing have been higher winter and spring temperatures. Although these temperature changes are partly controlled by the decadal-scale Pacific climate mode [Pacific decadal oscillation (PDO)], a separate and significant part of the variance is associated with a springtime warming trend that spans the PDO phases. © 2005 American Meteorological Society. 1931 The relationship between potentially erosive storm energy and daily rainfall quantity in England and Wales Davison P., Hutchins M.G., Anthony S.G. et al. Science of the Total Environment 2005 344/1-3 SPEC. ISS. (15-25) Erosive storm energy is the primary driver of soil detachment, and hence a major determinant of transfer of sediment and particulate phosphorus (P) to surface waters. Modelling of sediment and P loss at catchment scale, for example for the development of catchment and national mitigation policies, requires a spatially interpolated estimate of variation in erosion risk. To this end we present a method of estimating total rainfall erosivity, as kinetic energy (KE), for any location in England and Wales, from daily rainfall data or monthly climate data. Analysis of detailed, highresolution records from eleven contrasting sites showed strong predictive correlations between daily rainfall quantity and associated daily total kinetic energy estimated from hourly rainfall intensities. The coefficients showed systematic seasonal variation, with greatest KE per unit of rainfall in late summer and autumn months. In contrast, no systematic spatial variation was found as a function of location or continentality index. The relationships were integrated with probability distributions of rainfall quantity per rain day derived from spatial climate data (monthly rainfall totals and numbers of rain days). The resulting map captures and quantifies the effects of rainfall quantity and intensity patterns on risk of sediment detachment, and as such provides a critical input layer to catchment-scale models of sediment and P transfer. © 2005 Elsevier B.V. All rights reserved. 1932 Temporal analysis of the frequency and duration of low and high streamflow: Years of record needed to characterize streamflow variability Huh S., Dickey D.A., Meador M.R. and Ruhl K.E. Journal of Hydrology 2005 310/1-4 (78-94) A temporal analysis of the number and duration of exceedences of high- and low-flow thresholds was conducted to determine the number of years required to detect a level shift using data from Virginia, North Carolina, and South Carolina. Two methods were used - ordinary least squares assuming a known error variance and generalized least squares without a known error variance. Using ordinary least squares, the mean number of years required to detect a one standard deviation level shift in measures of low-flow variability was 57.2 (28.6 on either side of the break), compared to 40.0 years for measures of high-flow variability. These means become 57.6 and 41.6 when generalized least squares is used. 369 No significant relations between years and elevation or drainage area were detected (P>0.05). Cluster analysis did not suggest geographic patterns in years related to physiography or major hydrologic regions. Referring to the number of observations required to detect a one standard deviation shift as ‘characterizing’ the variability, it appears that at least 20 years of record on either side of a shift may be necessary to adequately characterize highflow variability. A longer streamflow record (about 30 years on either side) may be required to characterize low-flow variability. © 2005 Elsevier B.V. All rights reserved. 1933 Sensitivity analyses of a distributed catchment model to verify the model structure Sieber A. and Uhlenbrook S. Journal of Hydrology 2005 310/1-4 (216-235) Sensitivity analyses are valuable tools for identifying important model parameters, testing the model conceptualization, and improving the model structure. They help to apply the model efficiently and to enable a focussed planning of future research and field measurement. Two different methods were used for sensitivity analyses of the complex process-oriented model TAC D (tracer aided catchment model, distributed) that was applied to the meso-scale Brugga basin (40 km2 ) and the sub-basin St Wilhelmer Talbach (15.2 km2 ). Five simulations periods were investigated: two summer events, two snow melt induced events and one summer low flow period. The model was applied using 400 different parameter sets, which were generated by Monte Carlo simulations using latin hypercube sampling. The regional sensitivity analysis (RSA) allowed determining the most significant parameters for the complete simulation periods using a graphical method. The results of the regression-based sensitivity analysis were more detailed and complex. The temporal variability of the simulation sensitivity could be observed continuously and the significance of the parameters could be determined in a quantitative way. A dependency of the simulation sensitivity on initial- and boundary conditions and the temporal and spatial variability of the sensitivity to some model parameters was revealed by the regression-based sensitivity analysis. Thus, the difficulty of transferring the results to different time periods or model applications in other catchments became obvious. The analysis of the temporal course of the simulation sensitivity to parameter values in conjunction with simulated and measured additional data sets (precipitation, temperature, reservoir volumes etc.) gave further insight into the internal model behaviour and demonstrated the plausibility of the model structure and process conceptionalizations. © 2005 Elsevier B.V. All rights reserved. 1934 Characterisation of streamflow regimes in central Spain, based on relevant hydrobiological parameters Sanz D.B. and Del Jal´on D.G. Journal of Hydrology 2005 310/1-4 (266-279) The biotic composition, structure, and function of aquatic, wetland, and riparian ecosystem depend largely on the hydrological regime (Poff, N.L., Ward, J.V., 1990. Implications of streamflow variability and predictability for lotic community structure: a regional analysis of streamflow patterns. Can. J. Fisheries Aquat. Sci. 46, 1805-1818; Richter, B.D., Baumgartner, J.V., Wiginton, R., Braun, D.P., 1997 How much water does a river need? Freshwater Biol. 37, 231-249). Available flow data for many rivers in the world can be used to validate these ecological theories. There is a demand for studies that use hydrological indices to establish criteria, which serve to group together regime types at a local level. Once this has been done, these hydrologically similar groups can be used to identify communities of living organisms that are linked to specific aspects of the river’s behaviour. An approach to characterise flow regimes in the river network of the Tagus basin in Spain is presented. The river Tagus (ro Tajo) is one of the seven major rivers of the Iberian peninsula. All hydrological data were acquired from the measurements made in the Tagus basin, at 25 gauging stations. Twelve variables were derived for each gauged site to describe variability and predictability of average streamflow conditions, and to describe the frequency, timing and intensity of high flow and low flow extremes. A hierarchical clustering routine was used to identify similar groups of rivers as defined in terms of similar characteristics of their streamflow regime. The variables 370 HYDROLOGY were also examined with simple correlations to determine if multicollinearity occurred, in order to reject redundant parameters or to identify similar behaviour trends between pairs of parameters. Some parameters have shown a tendency to increase or decrease along the east-west axis, suggesting that some of the studied characteristics may have a geographical cause. Cluster analysis, with the values of the 12 parameters, reveals two main groups, each of which splits into two main subdivisions. One of these subgroups contains six rivers with similar characteristics, can be considered to be ‘classic regular rivers’, the stations in this first subgroup are mostly situated geographically close to each other. At the other end, we have found a subgroup, with a high variation of flows over the year and high flood flows; these rivers are highly irregular rivers with great changes. This regular-irregular gradient found between the groups is similar to that observed by others authors (Poff, N.L., Allan J.D., 1995. Functional organization of stream fish assemblages in relation to hydrological variability. Ecology 76, 606-627), and strong associations have been documented with compositions of populations and probably reflect differences in other similar important environmental factors. © 2005 Elsevier B.V. All rights reserved. 1935 Consensus seasonal Flood Forecasts and Warning Response System (FFWRS): An alternate for nonstructural flood management in Bangladesh Chowdhury Md.R. Environmental Management 2005 35/6 (716725) Despite advances in short-range flood forecasting and information dissemination systems in Bangladesh, the present system is less than satisfactory. This is because of short lead-time products, outdated dissemination networks, and lack of direct feedback from the end-user. One viable solution is to produce long-lead seasonal forecasts-the demand for which is significantly increasing in Bangladesh-and disseminate these products through the appropriate channels. As observed in other regions, the success of seasonal forecasts, in contrast to short-term forecast, depends on consensus among the participating institutions. The Flood Forecasting and Warning Response System (henceforth, FFWRS) has been found to be an important component in a comprehensive and participatory approach to seasonal flood management. A general consensus in producing seasonal forecasts can thus be achieved by enhancing the existing FFWRS. Therefore, the primary objective of this paper is to revisit and modify the framework of an ideal warning response system for issuance of consensus seasonal flood forecasts in Bangladesh. The five-stage FFWRS-i) Flood forecasting, ii) Forecast interpretation and message formulation, iii) Warning preparation and dissemination, iv) Responses, and v) Review and analysis-has been modified. To apply the concept of consensus forecast, a framework similar to that of the Southern African Regional Climate Outlook Forum (SARCOF) has been discussed. Finally, the need for a climate Outlook Fora has been emphasized for a comprehensive and participatory approach to seasonal flood hazard management in Bangladesh. © 2005 Springer Science+Business Media, Inc. 1936 Statistical guidelines for curve number generation Schneider L.E. and McCuen R.H. Journal of Irrigation and Drainage Engineering 2005 131/3 (282-290) The accuracy of runoff curve numbers (CNs) is unknown, and empirical evidence has suggested that with the current CN table, hydrological systems are being over designed - which some believe is due to a variable known as the initial abstraction coefficient (). Therefore, guidelines to produce a new CN table are needed. In order to develop this set of guidelines, the following objectives were met: Determination of CN and sensitivity, assessment of the accuracy of alternative methods for determining CNs, examination of the effect of the range of data, and evaluation of the potential change in hydrologic design due to a new table. Using measured and simulated data, the methods of estimating the CN were evaluated and assessed for accuracy. A new method using concepts of lognormal frequency was developed and found to be more accurate than the current practices. It was also found that is an insensitive variable when compared to the CN, and therefore, may complicate the optimal fitting of the CNs. Finally, it was determined that developing a new CN table would affect the estimation of peak discharge rates, and thus hydrologic designs. Therefore, it may be advantageous to develop a new CN table based on peak discharge measurements rather than depths of rainfall and runoff. Guidelines that should lead to a revised CN model with improved accuracy are provided. Journal of Irrigation and Drainage Engineering © ASCE. 1937 Probability distribution type of Canadian annual minimum streamflow Yue S. and Pilon P. Hydrological Sciences Journal 2005 50/3 (427-438) The method of L-moment ratio diagrams along with the averaged weighted distance (AWD) is applied to identify a probability distribution of annual minimum streamflow, namely annual minimum daily streamflow in II climatic regions of Canada. Across the entire country, the Pearson type III probability distribution is an acceptable distribution for describing annual minimum streamflow with the 3-parameter lognormal and log Pearson type III distributions as potential candidates. Some minor differences in the probability distribution type among different climatic regions are also observed, which may be taken into account in the selection of the distribution type of annual minimum streamflow. Copyright © 2005 IAHS Press. 1938 Improving generalization of artificial neural networks in rainfall-runoff modelling Giustolisi O. and Laucelli D. Hydrological Sciences Journal 2005 50/3 (439-457) Artificial neural networks (ANNs) are general-purpose techniques that can be used for nonlinear data-driven rainfall-runoff modelling. The key issue to construct a good model by means of ANNs is to understand their structural features and the problems related to their construction. Indeed, the quantity and quality of data, the type of noise and the mathematical properties of the algorithm for estimating the usual large number of parameters (weights) are crucial for the generalization performances of ANNs. However, it is well known that ANNs may suffer from poor generalization properties due to the high number of parameters and non-Gaussian data noise. Therefore, in the first part of this paper, the features and problems of ANNs are discussed. Eight Avoiding Overfitting Techniques are then presented, considering that these are methods for improving the generalization of ANNs. For this reason, they have been tested on two case studies - rainfall-runoff data from two drainage basins in the south of Italy - in order to gain insight into their propertics and to investigate if there is one that absolutely gives the best performance. Copyright © 2005 IAHS Press. 1939 Variability in the discharge of South American rivers and in climate Gara N.O. and Mechoso C.R. Hydrological Sciences Journal 2005 50/3 (459-478) Changes in trend and quasi-periodicities are sought in the time series of river discharges in all major South American basins. The relationship between trends and quasi-periodicities found and climate variations on interannual and longer time scales are discussed. Consideration of multiple rivers gives insight into the geographical extent of hydrological signals and climate impacts. It is found that the streamflow of all major rivers of South America has experienced an increased trend since the early 1970s. It is suggested that this simultaneity may reflect the impact of a largescale climate change. All the time series of river streamflows that were analysed show El Ni˜no-like periodicities. Only for La Plata Basin do these explain a larger part of the total variance than the other quasi-periodicities. There are two other quasi-oscillations in the time series analysed: one of them with a longer period - around 17 years - and the other of about 9 years. Previous work has related these oscillations to sea-surface temperature anomalies in the Atlantic Ocean. Copyright © 2005 IAHS Press. 1940 Trends in frequency of precipitation extremes in the Yangtze River basin, China: 1960-2003 Su B., Xiao B., Zhu D. and Jiang T. Hydrological Sciences Journal 2005 50/3 (479-492) The spatial distribution and trends in the frequency of precipitation extremes over the last 44 years (1960-2003), especially since 1990, have been analysed using daily precipitation data from 147 stations in the Yangtze River basin. The research results HYDROLOGY are as follows: (1) The 15 mm precipitation isohyet approximately divides the precipitation extremes (corresponding to the 95th percentile) of the stations in the middle and lower Yangtze reaches (higher) from those of the upper Yangtze reaches (lower). Also the starting time of the precipitation extremes in the middle and lower Yangtze reaches is earlier than of those in the upper Yangtze reaches. Precipitation extremes are concentrated mostly in June in the middle and lower Yangtze reaches, and July in the upper Yangtze reaches. (2) During the period 1960-2003, the first two decades had fewer precipitation extremes than the last two decades. There have been significant increasing trends and step changes in frequency of annual total precipitation extremes and precipitation extremes with a 1-5 day gap in the middle and lower Yangtze reaches. Precipitation extremes occur more frequently in shorter periods, separated by a few days. Precipitation extremes are also becoming more concentrated in the month with the highest frequency of extremes (June) in the middle and lower Yangtze reaches. In the upper Yangtze reaches, there is an upward tendency of extreme events in June. Increasing precipitation extremes in June for both the middle and lower, and the upper Yangtze reaches will increase the probability of flooding if the observed trends of the last 40 years continue into the future. Copyright © 2005 IAHS Press. 1941 The use of digital elevation models in the identification and characterization of catchments over different grid scales Hancock G.R. Hydrological Processes 2005 19/9 (1727-1749) This study examines the ability of well-known hydrological and geomorphological descriptors and statistics to differentiate between catchments with spatially varying geology, size and shape subject to the same climate in the Northern Territory, Australia. The effect of digital elevation model grid resolution on these statistics is also examined. Results demonstrate that catchment descriptors such as the area-slope relationship, cumulative area distribution and hypsometric curve can differentiate between catchments with different geology and resultant morphology, but catchment network statistics are insensitive to differences in geology. Examination of the effects of digital elevation model grid scale demonstrates that while considerable catchment information can be gained at digital elevation grids greater than 10 m by 10 m, hillslope and hydrological detail can be lost. Geomorphic descriptors such as the area-slope relationship, cumulative area distribution, width function and Strahler statistics were shown to be sensitive to digital elevation model grid scale, but the hypsometric curve was not. Consequently, caution is needed when deciding on an appropriate grid resolution as well as the interpretation and analysis of catchment properties at grid scales greater than that for optimal hillslope and area aggregation definition. Copyright © 2005 John Wiley & Sons, Ltd. 1942 Estimation of Columbia River virgin flow: 1879 to 1928 Naik P.K. and Jay D.A. Hydrological Processes 2005 19/9 (18071824) The Columbia River is a major source of and conduit for Pacific Northwest economic activity, and is one of the more heavily modified rivers in North America. Understanding human and climate-induced changes in its hydrologic properties is, therefore, vital. Long streamflow records are essential to determining how runoff has changed over time, and Columbia River daily streamflow record at The Dalles began in 1878. To understand and separate anthropogenic and climate effects, however, it is also necessary to have a basin-scale estimate of virgin or naturalized flow. The United States Geological Survey has calculated a monthly averaged adjusted river flow at The Dalles for 1879-1999 that accounts for the effects of flow regulation. The Bonneville Power Administration has estimated the monthly averaged virgin flow at The Dalles, i.e. the flow in the absence of both flow regulation and irrigation depletion for 1929-89. We have estimated the monthly virgin flow of the Columbia River at The Dalles from records of irrigated area for the missing early years, i.e. for the period 1879-1928. In addition, to allow hindcasting of a virgin flow sediment transport for the system, a daily virgin flow index with realistic higher moments and spectral properties has been calculated. Examination of the virgin flow record shows that climate change since the late 19th century has decreased annual average flow volume by > 7%; irrigation depletion has reduced 371 the flow by another 7%. Copyright © 2005 John Wiley & Sons, Ltd. 1943 Sensitivity of soil moisture field evolution to rainfall forcing Yoo C., Kim S.- J. and Valdes J.B. Hydrological Processes 2005 19/9 (1855-1869) In this paper the temporal behaviour of soil moisture is modelled and statistically characterized by use of the zero-dimensional model for soil moisture dynamics and the rectangular pulses Poisson process model for rain all forcing. The mean, covariance and spectral density function of soil moisture (both instantaneous and locally averaged cases) are analytically derived to evaluate its sensitivity to the model parameters. Finally, the probability density function of soil moisture is derived to evaluate the effect of rainfall forcing. All the model parameters used have been tuned to the Monsoon ‘90 data. Results can be summarized as follows. (1) Only the soil moisture model parameters ( and nZr ) are found to affect the autocorrelation function in a distinguishable manner. On the other hand, both the rainfall model parameter () and the effective soil depth (nZr ) are found to be of impact to the soil moisture spectrum. However, as the smoothing (or damping) effect of soil is so dominant, about 20% variation of one parameter seems not to affect significantly the second-order statistics of soil moisture. (2) More difference can be found by applying a longer averaging time, which is found to obviously decrease the variance but increase the correlation even though no overlapping between neighbouring soil moisture data was allowed. (3) Among rainfall model parameters, the arrival rate was found to be most important for the soil moisture evolution. When increasing the arrival rate of rainfall, the histogram of soil moisture shifts its peak to a certain value as well as becomes more concentrated around the peak. However, by decreasing the arrival rate of rainfall, a much smaller (almost to zero) mean value of soil moisture was estimated, even though the total volume of rainfall remained constant. This indicates that desertification may take place without decreasing the total volume of rainfall. Copyright © 2005 John Wiley & Sons, Ltd. 1944 Characteristics of surface runoff and throughflow in a purple soil of Southwestern China under various rainfall events Liu G., Tian G., Shu D. et al. Hydrological Processes 2005 19/9 (1883-1891) In order to harvest runoff to palliate water disaster as well as effectively manage irrigation and fertilizer application in the studied region, it is necessary to better understand the runoff processes. A newly designed runoff collection system for a plot scale was used to partition runoff under contrasting rainfall events into surface flow and subsurface flow to obtain characteristics of surface runoff and throughflow in a purple soil (Regosols in FAO taxonomy, Entisol in USDA taxonomy) of Sichuan, China. Under small rainfall (shower and drizzle), only surface runoff was observed. It is noted that, under shower, particularly with antecedent dry soil conditions, the highest peak surface runoff significantly lagged behind that of rainfall, because air-locked soil pores of the top layer appeared temporally. Under rainstorm and downpour, surface runoff and throughflow both commenced and showed hysteresis. The hydrograph of surface runoff better resembled that of rainfall than throughflow did. The durations of throughflow discharge of post-rainfall-end were near the same (within 24 h) under various rainfalls and rather dependent upon the soil properties than the rainfall characteristics. Throughflow is about 60-90% of total runoff, and especially significant in a ploughed layer under downpour. The chloride concentration of throughflow was over twice that of surface runoff and rainfall, implying that throughflow contains more nutrients than surface runoff. Presumably, surface runoff was primarily governed by an infiltration-excess or saturated excess-infiltration mechanism under unsaturated or saturated soil conditions. Therefore, the management of water and fertilizer, and the harvesting of water flow in the ploughed soil layer, should be emphasized in this region. Copyright © 2005 John Wiley & Sons, Ltd. 1945 Temporal variation of river flow renewability in the middle Yellow River and the influencing factors Xu J. Hydrological Processes 2005 19/9 (1871-1882) 372 HYDROLOGY In the past 30 years, the measured annual river flow of the Yellow River has declined significantly. After adding the diverted water back to get the ‘natural’ annual river flow, the tendency of decrease can still be seen. This indicates that the river flow renewability of the Yellow River has changed. The river flow renewability is indexed as the ratio of annual ‘natural’ river flow to annual precipitation over a river drainage basin, where the ‘natural’ river flow is the measured annual river flow plus the annual ‘net’ water diversion from the river. By using this index, based on the data from the drainage area between Hekouzhen and Longmen stations on the middle Yellow River, a study has been made of the river flow renewability of the Yellow River in the changing environment of the past 50 years. The river flow renewability index (Irr ) in the drainage area between Hekouzhen and Longmen in the middle Yellow River basin has been found to decline significantly with time. In the meantime, annual precipitation decreased, annual air temperature increased, but the area of water and soil conservation measures has been increased. It has been found that Irr is positively correlated with the areal averaged annual precipitation, but negatively correlated with annual air temperature. There is close, negative correlation between Irr and the area of water and soil conservation measures including land terracing, tree and grass planting and checkdam building, implying that water and soil conservation measures have reduced the river flow renewability. Copyright © 2005 John Wiley & Sons, Ltd. 1946 A modified Xinanjiang model and its application in northern China Hu C., Guo S., Xiong L. and Peng D. Nordic Hydrology 2005 36/2 (175-192) The Xinanjiang model has been widely used in the humid regions in southern China as a basic tool for rainfall - runoff simulation, flood forecasting and water resources planning and management. However, its performance in the arid and semi-arid regions of northern China is usually not so good as in the humid regions. A modified Xinanjiang model, in which runoff generation in the watershed is based on both infiltration excess and saturation excess runoff mechanisms, is presented and discussed. Three different watersheds are selected for assessing and comparing the performance of the Xinanjiang model, the modified Xinanjiang model, the VIC model and the TOPMODEL in rainfall runoff simulation. It is found that the modified Xinanjiang model performs better than the Xinanjiang model, and the models considering the Horton and Dunne runoff generation mechanisms are slightly better than those models considering the single runoff generation mechanism in semi-arid areas. It is suggested that the infiltration excess runoff mechanism should be included in rainfall - runoff models in and and semi-arid regions. © IWA Publishing 2005. 1947 Regional flow duration curve for a Himalayan river Chenab Arora M., Goel N.K., Singh P. and Singh R.D. Nordic Hydrology 2005 36/2 (193-206) This study is carried out with the objective of examining the effect of altitude on water availability estimates for the various sub-basins of the Chenab river basin (mean elevation of the basin is 3600 m), which is a snow-fed Himalayan river basin located in the western Himalayas. This basin covers all three Himalayan ranges, i.e. outer, middle and greater Himalayas. For this study, the daily flow data of 11 gauging sites varying from 14 years to 23 years in the Chenab river basin are utilised. The other important information related to the physiography, hydrology and meteorology, etc, for the region are derived from the available literature and maps. The daily flow data of nine gauging sites are utilised for developing the regional relationships for water availability computations. These relationships are tested over the remaining two gauging sites. The regional relationships are developed using three different approaches. These approaches include: (i) parameter regionalisation for individual gauged sites of selected probability distribution, (ii) regionalisation of dependable flows and (iii) parameter regionalisation for the region as a whole of the selected probability distribution. The different methods are compared and discussed in detail. It is observed that the flow for a given dependability increases with catchment area and decreases with altitude. The flows of the catchments at higher altitudes exhibit larger variability in comparison to the catchments at lower altitudes. The regional relationships are recommended for the use of field engineers. © IWA Publishing 2005. 1948 Hidrological effects of the electrical and agricultural uses in the basin of the Laja river (center-south of Chile) (Spanish) (Efectos hidrol´ogicos de los usos el´ectrico y agrcola en la cuenca del ro Laja (Chile centro-sur)) Mardones M. and Vargas J. Revista de Geografia Norte Grande 2005 -/33 (89-102) Surface hydrological responses to hydroelectric and agricultural use, are evaluated of the Laja river basin (Chile) and the associated lake Laja. A drop of 27 m is observed in the lake water level with respect to normal hydrologic regime, for the 1972 to 1999 period; it correlates directly with hydroelectric power production (r2 = 0,78). In addition, the drainage network of the upper river basin has been modified completely. The impact of this use on the hydrologic balance of the Andean sector is weak (-3,7% of total precipitations), due to lack of consumption. In the lower basin, water consumption for irrigation corresponds to an annual average of 22,8% of the Laja river volume, resulting in a negative hydrological balance equivalent to 36,8%, of the total annual rainfall. 1949 Linking riparian dynamics and groundwater: An ecohydrologic approach to modeling groundwater and riparian vegetation Baird K.J., Stromberg J.C. and Maddock III T. Environmental Management 2005 36/4 (551-564) The growing use of global freshwater supplies is increasing the need for improved modeling of the linkage between groundwater and riparian vegetation. Traditional groundwater models such as MODFLOW have been used to predict changes in regional groundwater levels, and thus riparian vegetation potential attributable to anthropogenic water use. This article describes an approach that improves on these modeling techniques through several innovations. First, evapotranspiration from riparian/wetland systems is modeled in a manner that more realistically reflects plant ecophysiology and vegetation complexity. In the authors’ model programs (RIP-ET and PRE-RIP-ET), the single, monotonically increasing evapotranspiration flux curve in traditional groundwater models is replaced with a set of ecophysiologically based curves, one for each plant functional group present. For each group, the curve simulates transpiration declines that occur both as water levels decline below rooting depths and as waters rise to levels that produce anoxic soil conditions. Accuracy is further improved by more effective spatial handling of vegetation distribution, which allows modeling of surface elevation and depth to water for multiple vegetation types within each large model cell. The use of RIP-ET in groundwater models can improve the accuracy of basin scale estimates of riparian evapotranspiration rates, riparian vegetation water requirements, and water budgets. Two case studies are used to demonstrate that RIP-ET produces significantly different evapotranspiration estimates than the traditional method. When combined with vegetation mapping and a supporting program (RIP-GIS), RIPET also enables predictions of riparian vegetation response to water use and development scenarios. The RIP-GIS program links the head distribution from MODFLOW with surface digital elevation models, producing moderate- to high-resolution depth-to-groundwater maps. Together with information on plant rooting depths, these can be used to predict vegetation response to water allocation decisions. The different evapotranspiration outcomes produced by traditional and RIP-ET approaches affect resulting interpretations of hydro-vegetation dynamics, including the effects of groundwater pumping stress on existing habitats, and thus affect subsequent policy decisions. © 2005 Springer Science+Business Media, Inc. 1950 Regional hydrological modelling in Benin (West Africa): Uncertainty issues versus scenarios of expected future environmental change Bormann H. Physics and Chemistry of the Earth 2005 30/8-10 (472-484) The conceptual, hydrological UHP model was used to calculate regional and seasonal to long-term water fluxes of several meso- HYDROLOGY scale catchments within the upper Ou´em´e basin in central Benin. To analyse the quality of the simulations in addition to standard model validation techniques (e.g., split sampling test, multi-site and multi-scale validation), different methods were applied to assess the orders of magnitude of input data uncertainty and model uncertainty (e.g., Monte-Carlo-analysis, rainfall data analysis). To evaluate the suitability of the model to be used for environmental change studies, finally the detected uncertainties were set into relation to the effects of environmental change scenarios for different regional scale catchments in central Benin. Main result was the fact that all "signal-to-noise ratios" of model-scenariouncertainty combinations were positive and most of the ratios were even high. Thus on the seasonal time scale, the environmental effects calculated by the model were significantly larger than the uncertainties caused by imperfect model parameters and input data. Nevertheless uncertainties were detected to have a potentially significant impact on the simulation results (esp. on the event scale) although the model calculates the water fluxes of the subhumid catchments well with regard to several statistical quality measures (water balance, model efficiency, coefficient of variation, etc.). Dominating uncertainties are the input data (rainfall in particular), which may cause both errors in the calculated hydrological processes at the event scale and biases in the long-term water balance. Therefore implausible data sets need to be rejected. With regard to the scenarios all environmental changes may cause significant effects on the long-term water balance: land use change, soil degradation and decreasing rainfall. Concerning the total annual stream flow the realistic scenarios of an expected rainfall decrease and an increasing soil degradation due to land use change in the next 20 years partly leads to a compensation of the individual effects (e.g., decrease caused by decreasing rainfall versus increase caused by decreasing soil storage capacity and increasing curve number), while other water related indicators (e.g., the length of the vegetation period defined by the time of exceeding a certain root zone soil moisture; annual actual evapotranspiration as an indicator for plant productivity) decrease significantly. © 2005 Elsevier Ltd. All rights reserved. 1951 Assessing the effects of land use change on soil physical properties and hydrological processes in the sub-humid tropical environment of West Africa Giertz S., Junge B. and Diekkr¨uger B. Physics and Chemistry of the Earth 2005 30/8-10 (485-496) Land use is a key parameter in the hydrologic cycle. Tropical Africa is affected by intense land use change since decades, particularly deforestation and conversion to agricultural land. The aim of this study is to analyse the effects of land use change on the hydrologic processes and soil physical properties in a small catchment (Aguima catchment) in central Benin. Results from pedological, pedobiological and hydrological investigations within the Aguima catchment were taken into account. The effects of land use change on hydrologic processes were analysed by comparing two sub-catchments of the Aguima catchment with different land use (savannah/forest and agricultural land use). The study is part of the GLOWA IMPETUS project, which examines the effects of global change on the water cycle and water availability on a regional scale in Morocco and Benin. The investigations of this study revealed that due to reduced activity of the macrofauna the infiltration capacity is significantly lower in cultivated soils than in savannah and forest. This causes higher surface runoff and soil loss rates, which was also determined on erosion plots. The increased soil loss on fields has effects on soil physical properties like increase of gravel content and reduction of field capacity. The impact of reduced vegetation cover on the soil water dynamics was examined with soil moisture measurements on different land use. Due to higher evapotranspiration and water withdrawal the soil water content on forest and savannah plots was lower than on agricultural fields. The difference in the water yield of the forested and cultivated catchments was over 120 mm in the dry year 2001 and about 70 mm in the wetter year 2002. © 2005 Pubilshed by Elsevier Ltd. 373 1952 The application of simple methods using remote sensing data for the regional validation of a semidistributed hydrological catchment model Wegehenkel M., Jochheim H. and Kersebaum K.C. Physics and Chemistry of the Earth 2005 30/8-10 (575-587) Simulation runs of a semidistributed hydrological conceptual catchment model were performed using a spatial data set from a mesoscale catchment located at the moraine landscape of NorthEast Germany. The simulation quality of the model was estimated by comparing measured daily actual evapotranspiration rates, soil water contents and discharge rates with the corresponding simulated model outputs. Additionally, six LandsatTM5-subsets covering the catchment were used to calculate the Normalized Difference Vegetation Index (NDVI). These NDVIdistributions were compared with the corresponding simulated regional distributions of actual evapotranspiration (ETr) rates. A visual analysis of the spatial distribution patterns of the NDVI and of the simulated ETr-rates shows some correspondences. However, the spatial variability of the NDVI-patterns was distinctly higher in comparison with the variability of the ETr-rates calculated by the model. We analyzed the coefficients of correlation R between the patterns of the NDVI and the simulated ETr-rates separately for the land cover classes arable land, meadows, coniferous, deciduous and mixed forests. For arable land R ranged within 0.77 and 0.10, for meadows within 0.79 and 0.10, for coniferous forests between 0.73 and 0.10, for deciduous forests between 0.88 and 0.10 as well as for mixed forests between 0.67 and 0.10. The spatial distributions of simulated high and low ETr-rates were mainly correlated with the spatial distributions of forest areas, arable land, water bodies and settlements. © 2005 Elsevier Ltd. All rights reserved. 1953 Runoff modelling using radar data and flow measurements in a stochastic state space approach Kr¨amer S., Grum M., Verworn H.- R. and Redder A. Water Science and Technology 2005 52/5 (1-8) In urban drainage the estimation of runoff with the help of models is a complex task. This is in part due to the fact that rainfall, the most important input to urban drainage modelling, is highly uncertain. Added to the uncertainty of rainfall is the complexity of performing accurate flow measurements. In terms of deterministic modelling techniques these are needed for calibration and evaluation of the applied model. Therefore, the uncertainties of rainfall and flow measurements have a severe impact on the model parameters and results. To overcome these problems a new methodology has been developed which is based on simple rain plane and runoff models that are incorporated into a stochastic state space model approach. The state estimation is done by using the extended Kalman filter in combination with a maximum likelihood criterion and an off-line optimization routine. This paper presents the results of this new methodology with respect to the combined consideration of uncertainties in distributed rainfall derived from radar data and uncertainties in measured flows in an urban catchment within the Emscher river basin, Germany. © IWA Publishing 2005. 1954 Surface models for coupled modelling of runoff and sewer flow in urban areas Ettrich N., Steiner K., Thomas M. and Rothe R. Water Science and Technology 2005 52/5 (25-33) Traditional methods fail for the purpose of simulating the complete flow process in urban areas as a consequence of heavy rainfall and as required by the European Standard EN-752 since the bi-directional coupling between sewer and surface is not properly handled. The new methodology, developed in the EUREKAproject RisUrSim, solves this problem by carrying out the runoff on the basis of shallow water equations solved on high-resolution surface grids. Exchange nodes between the sewer and the surface, like inlets and manholes, are located in the computational grid and water leaving the sewer in case of surcharge is further distributed on the surface. Dense topographical information is needed to build a model suitable for hydrodynamic runoff calculations; in urban areas, in addition, many line-shaped elements like houses, curbs, etc. guide the runoff of water and require polygonal input. Airborne data collection methods offer a great chance to economically gather densely sampled input data. © IWA Publishing 2005. 374 HYDROLOGY 1955 Development and implementation of a real time control strategy for the sewer system of the city of Vienna Fuchs L. and Beeneken T. Water Science and Technology 2005 52/5 (187-194) The paper describes the realization of a real-time control for the Vienna sewer system. The project is scheduled for completion for 2004. The 3.5 year project comprises all planning stages starting with the recording of data up to the planning of measuring and controlling units. The concrete steps of the planning stages are explained. A measuring system including 25 rainfall measurements, 40 flow measurements and 20 water level measurements is implemented as an online system. This measuring system is designed to achieve two objectives, on the one hand the real-time control and on the other hand the callibration of the model that is used for the hydrodynamic sewer system simulation. The approx. 53,000 pipes have served to generate a coarse network of no more than approx. 2,600 pipes. The area data were derived with high accuracy from available aerial photograph interpretations. With simulation runs of a rule-based control software the system operation was examined. A self-learning system will improve the rule basis. A forecasting model that uses weather observation radar will additionally influence the controlling decisions. The findings from the investigations are immediately considered in the planning of measuring and control units. The simulated results for the first phase of implementation, which demonstrate the benefit of RTC for the Vienna sewer system, are explained. © IWA Publishing 2005. 1956 Flooding in the future - Predicting climate change, risks and responses in urban areas Ashley R.M., Balmfort D.J., Saul A.J. and Blanskby J.D. Water Science and Technology 2005 52/5 (265-273) Engineering infrastructure is provided at high cost and is expected to have a useful operational life of decades. However, it is clear that the future is uncertain. Traditional approaches to designing and operating urban storm drainage assets have relied on past performance of natural systems and the ability to extrapolate this performance, together with that of the assets across the usable lifetime. Whether or not climate change is going to significantly after future weather patterns in Europe, it is clear that it is now incumbent on designers and operators of storm drainage systems to prepare for greater uncertainty in the effectiveness of storm drainage systems. A recent UK Government study considered the potential effects of climate and socio-economic change in the UK in terms of four future scenarios and what the implications are for the performance of existing storm drainage facilities. In this paper the modelling that was undertaken to try to quantify the changes in risk, together with the effectiveness of responses in managing that risk, are described. It shows that flood risks may increase by a factor of almost 30 times and that traditional engineering measures alone are unlikely to be able to provide protection. © IWA Publishing 2005. 1957 SIPSON - Simulation of interaction between pipe flow and surface overland flow in networks ˇ et al. Water SciDjordjevi´c S., Prodanovi´c D., Maksimovi´c C. ence and Technology 2005 52/5 (275-283) The new simulation model, named SIPSON, based on the Preissmann finite difference method and the conjugate gradient method, is presented in the paper. This model simulates conditions when the hydraulic capacity of a sewer systems exceeded, pipe flow is pressurized, the water flows out from the piped system to the streets, and the inlets cannot capture all the runoff. In the mathematical model, buried structures and pipelines, together with surface channels, make a horizontally and vertically looped network involving a complex interaction of flows. In this paper, special internal boundary conditions related to equivalent inlets are discussed. Procedures are described for the simulation of manhole cover loss, basement flooding, the representation of street geometry, and the distribution of runoff hydrographs between surface and underground networks. All these procedures are built into the simulation model. Relevant issues are illustrated on a set of examples, focusing on specific parameters and comparison with field measurements of flooding of the Motilal ki Chal catchment (Indore, India). Satisfactory agreement of observed and simulated hydrographs and maximum surface flooding levels is obtained. It is concluded that the presented approach is an improvement compared to the standard "virtual reservoir" approach commonly applied in most of the models. © IWA Publishing 2005. 1958 Remarks about definition and classification of floods (Polish) (W sprawie definicji powodzi) Byczkowski A. Przeglad Geofizyczny 2005 50/1-2 (73-76) As generally assumed a flood occurs when the river overtops and inundates the floodplain. The paper suggests extension of the definition and classification of floods. The flood should be defined as the phenomenon of inundation of the certain territory with the waters of various genesis affecting: threat of human life as well as the economical and moral losses. In proposed classification the floods are differentiated on: the river ones, local accumulation of the rain or snowmelt water and coastal floods. 1959 The Orinoco River basin: Hydrographic view and its hydrological balance (Spanish) (La cuenca del ro Orinoco: Visi´on hidrogr´afica y balance hdrico) Silva Le´on G. Revista Geografica Venezolana 2005 46/1 (75-108) The international Orinoco River basin is described, referring to location, limits, dimensions, extension, regions, cities, fluvial integration, climate, runoff regime and main tributaries. Then, the hydrological balance of the basin is approached, simplifying the general equation to the case of the annual average, in which the contribution by rainfall is equal to the exit by runoff and evapotranspiration. First, a balance adjusted to the historical average of 14.850 m3/s that has the Orinoco River in Puerto Ayacucho is accomplished, to whose basin of 342.000 Km2 an average of 2.660 mm/year of rainfall and 1.260 mm/year of evapotranspiration is calculated, resulting in good hydrological yield indicatives: productivity of 43 l/s/Km2 and runoff coefficient of 51%. This balance is extrapolated to other points of the Orinoco River, up streams and down streams, including its affluents. Finally, preliminary balances are obtained from hydrographic regions and from countries. 1960 Flow regime alterations under changing climate in two river basins: Implications for freshwater ecosystems Gibson C.A., Meyer J.L., Poff N.L. et al. River Research and Applications 2005 21/8 (849-864) We examined impacts of future climate scenarios on flow regimes and how predicted changes might affect river ecosystems. We examined two case studies: Cle Elum River, Washington, and Chattahoochee-Apalachicola River Basin, Georgia and Florida. These rivers had available downscaled global circulation model (GCM) data and allowed us to analyse the effects of future climate scenarios on rivers with (1) different hydrographs, (2) high future water demands, and (3) a river-floodplain system. We compared observed flow regimes to those predicted under future climate scenarios to describe the extent and type of changes predicted to occur. Daily stream flow under future climate scenarios was created by either statistically downscaling GCMs (Cle Elum) or creating a regression model between climatological parameters predicted from GCMs and stream flow (ChattahoocheeApalachicola). Flow regimes were examined for changes from current conditions with respect to ecologically relevant features including the magnitude and timing of minimum and maximum flows. The Cle Elum’s hydrograph under future climate scenarios showed a dramatic shift in the timing of peak flows and lower low flow of a longer duration. These changes could mean higher summer water temperatures, lower summer dissolved oxygen, and reduced survival of larval fishes. The Chattahoochee-Apalachicola basin is heavily impacted by dams and water withdrawals for human consumption; therefore, we made comparisons between pre-large dam conditions, current conditions, current conditions with future demand, and future climate scenarios with future demand to separate climate change effects and other anthropogenic impacts. Dam construction, future climate, and future demand decreased the flow variability of the river. In addition, minimum flows were lower under future climate scenarios. These changes could decrease the connectivity of the channel and the floodplain, decrease habitat availability, and potentially lower the ability of the river to assimilate wastewater treatment plant effluent. Our study illustrates the types of changes that river ecosystems might HYDROLOGY experience under future climates. Copyright © 2005 John Wiley & Sons, Ltd. 1961 Effects of stream flow intermittency on riparian vegetation of a semiarid region river (San Pedro River, Arizona) Stromberg J.C., Bagstad K.J., Leenhouts J.M. et al. River Research and Applications 2005 21/8 (925-938) The San Pedro River in the southwestern United States retains a natural flood regime and has several reaches with perennial stream flow and shallow ground water. However, much of the river flows intermittently. Urbanization-linked declines in regional ground-water levels have raised concerns over the future status of the riverine ecosystem in some parts of the river, while restoration-linked decreases in agricultural ground-water pumping are expected to increase stream flows in other parts. This study describes the response of the streamside herbaceous vegetation to changes in stream flow permanence. During the early summer dry season, streamside herbaceous cover and species richness declined continuously across spatial gradients of flow permanence, and composition shifted from hydric to mesic species at sites with more intermittent flow. Hydrologic threshold values were evident for one plant functional group: Schoenoplectus acutus, Juncus torreyi, and other hydric riparian plants declined sharply in cover with loss of perennial stream flow. In contrast, cover of mesic riparian perennials (including Cynodon dactylon, an introduced species) increased at sites with intermittent flow. Patterns of hydric and mesic riparian annuals varied by season: in the early summer dry season their cover declined continuously as flow became more intermittent, while in the late summer wet season their cover increased as the flow became more intermittent. Periodic drought at the intermittent sites may increase opportunities for establishment of these annuals during the monsoonal flood season. During the late summer flood season, stream flow was present at most sites, and fewer vegetation traits were correlated with flow permanence; cover and richness were correlated with other environmental factors including site elevation and substrate nitrate level and particle size. Although perennial-flow and intermittent-flow sites support different streamside plant communities, all of the plant functional groups are abundant at perennial-flow sites when viewing the ecosystem at broader spatial and temporal scales: mesic riparian perennials are common in the floodplain zone adjacent to the river channel and late-summer hydric and mesic annuals are periodically abundant after large floods. Copyright © 2005 John Wiley & Sons, Ltd. 1962 Integration of weather radar data into a raster GIS framework for improved flood estimation Yu B., Seed A., Pu L. and Malone T. Atmospheric Science Letters 2005 6/1 (66-70) Weather radar data were used to estimate rainfall fields at 2-km resolution for a large flood event in 1999 in south-east Queensland, Australia, and subsequently integrated with a raster-based hydrologic model (RAMS) for runoff generation and flow routing. Gauge-based and radar-based temporal storm patterns are quite similar for the storm event. Agreement between gaugebased and radar-based event rainfall totals is not as good as that for spatially averaged intensities. Correlation between gaugebased and radar-based rainfall measurements is not sensitive to the exponent value in the Z-R relationship for the event tested. The hydrologic model with 4 parameters for the entire 13 600km2 catchment works very well when calibrated against the measured hydrograph. An overall model efficiency of 0.61 is achieved with respect to predicted peak discharge for 17 validation sites in the catchment. RAMS compares favourably with URBS, a rainfall-runoff model using gauge-based measurements currently in use for flood forecasting purposes. Copyright © 2005 Royal Meteorological Society. 1963 Retrospective comparison of Watershed Analysis Risk Management Framework and Hydrologic Simulation Program Fortran applications to Mica Creek Watershed Chen C.W., Herr J.W., Goldstein R.A. et al. Journal of Environmental Engineering 2005 131/9 (1277-1284) As part of an ongoing watershed model comparison program for forested watersheds, Watershed Analysis Risk Management Framework (WARMF V5.18) and Hydrologic Simulation Pro- 375 gram Fortran (HSPF V10) were independently applied to the Mica Creek Watershed in Idaho. A comprehensive model comparison was made in terms of watershed delineation, hydrologic formulations, model parameterization, meteorological data, hydrologic calibration, and hydrologic verification. Comparison was not made for water quality, which was not simulated in the HSPF application. It was concluded that WARMF is a mechanistic model structured to simulate the hydrologic processes, whereas HSPF is an empirical water budget model. The WARMF is suitable for application to forested watersheds. It successfully predicted stream flows comparable to measured values. The HSPF results were also good, if one ignores an unrealistic amount of water loss to inactive groundwater and an empirical treatment of rain-on-snow events. Journal of Environmental Engineering © ASCE. 1964 Runoff and soil moisture relationships in a small forested basin in the Sistema Central Ranges (Spain) Martnez- Fern´andez J., Ceballos A., Casado S. et al. IAHS-AISH Publication 2005 -/299 (31-36) In the present work we analyse runoff yield in a small Mediterranean basin with respect to soil moisture dynamics. The aim was to observe the behaviour of the basin in terms of the generation of runoff in periods in which maximum water deficit occurs in the soil. Despite the abundant precipitation in the mountainous regions of the Mediterranean area, the joint action of the climatic conditions prevailing in the growing season and water interception and consumption by the forest may seriously affect the generation of runoff over a considerable part of the year. 1965 The effects over time of an arterial drainage scheme on the flood magnitude-return period relations Bhattarai K.P. and O’Connor H.M. IAHS-AISH Publication 2005 -/299 (67-74) Arterial Drainage Schemes (ADSs) were implemented on Irish rivers for the purposes of improving the land drainage and reducing the frequency and extent of overland flooding. Such ADSs mainly involved the deepening and widening of the river channels in order to increase their discharge-carrying capacity, thereby, affecting not only the basins’ response to rainfall but also their peak discharge (QT )-return period (T) relation. Earlier Irish studies involving the effects of ADS on a catchment’s QT -T relation found that the post-drainage QT of an ADS-catchment was always larger, for the same T, in comparison to its pre-drainage counterpart. The current study focuses on investigating whether such effects have persisted in the ADS-catchments, or died out with the passage of time. Results of analysis on 16 ADS and 6non-ADS catchments show that the ADS (post-1945)-catchments have experienced major changes in the QT -T relation over time, whereas such changes are less pronounced in other catchments. 1966 The change in flood regime along the Lower Jordan River: Its influence on flood plain land use Klein M. IAHS-AISH Publication 2005 -/299 (205-216) Cooperation among riparian parties along the Lower Jordan River (LJR) may promote development of the region’s natural resources. Cooperation requires understanding of the river’s present flow regime, water quality and current land use in the flood plain. The average annual flow in the LJR has decreased from 1166 Mm3 year-1 (1926-1945) to 167 Mm3 year-1 (19782000), of which about 70% (120 Mm3 ), are of good water quality. Due to the extremely dry years, the allocation of water to the state of Jordan of 50 Mm3 year-1 after the 1994 Peace Agreement and the barrage built on the Yarmouk (YR) at Adasia, the average yearly flow of the last decade was less than 120 Mm3 . At present the river’s cross section area is in a re-adjustment phase and is becoming much smaller. The LJR flood plain is not inhabited and the population lives outside the area, yet the flood plain is used for agricultural purposes. 1967 Hybrid model for derivation of synthetic unit hydrograph Bhunya P.K., Ghosh N.C., Mishra S.K. et al. Journal of Hydrologic Engineering 2005 10/6 (458-467) 376 HYDROLOGY Splitting the Nash single linear reservoir into two serially connected reservoirs of unequal storage coefficients (one hybrid unit) for a physically realistic response, a hybrid model is introduced for derivation of a synthetic unit hydrograph. Empirical relations are given for estimation of the two storage coefficients from known peak flow (qp ) and time to peak (tp ). The hybrid model with two serially connected units is found to work significantly better than the most widely used methods such as those of Snyder, the Soil Conservation Service (SCS), and the two-parameter gamma distribution when tested on synthetically generated data and the data from four catchments from India and one from Turkey. The workability of the proposed approach was also tested for partial and no data availability situations. Journal of Hydrologic Engineering © ASCE. 1968 Analyses of flow mechanism based on master recession curves Mizumura K. Journal of Hydrologic Engineering 2005 10/6 (468476) A theoretical analysis derives that master recession curves on log paper indicate the physical occurrence of stream flows. The master recession curves in this study are generated by one-dimensional overland flow without and with lateral flow and groundwater flow. One-dimensional overland flow is also classified by assumption of the energy slope and kinematic or diffusion wave models. These theoretical results are coincident with the slopes of the observed master recession curves of the hydrographs. The slopes of the master recession curve of water depth and the discharge hydrographs on the log paper designate the predominancy of river discharge. These results predict the governing causes of river discharge occurrence during the master recession period. When the lateral flow is predominant, the master recession curve is not definitely determined. The observation data indicate that the slopes of the master recession curves are found to be independent of the initial conditions of channel flows, spatially varied rainfalls, moving rainstorms, etc. Journal of Hydrologic Engineering © ASCE. 1969 Comparison of several flood forecasting models in Yangtze River Chau K.W., Wu C.L. and Li Y.S. Journal of Hydrologic Engineering 2005 10/6 (485-491) In a flood-prone region, quick and accurate flood forecasting is imperative. It can extend the lead time for issuing disaster warnings and allow sufficient time for habitants in hazardous areas to take appropriate action, such as evacuation. In this paper, two hybrid models based on recent artificial intelligence technology, namely, the genetic algorithm-based artificial neural network (ANN-GA) and the adaptive-network-based fuzzy inference system (ANFIS), are employed for flood forecasting in a channel reach of the Yangtze River in China. An empirical linear regression model is used as the benchmark for comparison of their performances. Water levels at a downstream station, HanKou, are forecasted by using known water levels at the upstream station, Luo-Shan. When cautious treatment is made to avoid overfitting, both hybrid algorithms produce better accuracy in performance than the linear regression model. The ANFIS model is found to be optimal, but it entails a large number of parameters. The performance of the ANN-GA model is also good, yet it requires longer computation time and additional modeling parameters. Journal of Hydrologic Engineering © ASCE. 1970 Optimal location of infiltration-based best management practices for storm water management Perez- Pedini C., Limbrunner J.F. and Vogel R.M. Journal of Water Resources Planning and Management 2005 131/6 (441448) A distributed hydrologic model of an urban watershed in the northeast United States was developed and combined with a genetic algorithm to determine the optimal location of infiltration-based best management practices (BMPs) for storm water management. The distributed, event-based hydrologic model integrates the curve number method with a distributed hydrologic network model of the catchment using a system of 4,533 hydrologic response units (HRUs). The infiltration-based BMP was conceptualized as an element that alters the infiltration/runoff partitioning of the HRUs in which it was applied. The results indicate that the optimal location and number of BMPs is a complex function of watershed network connectivity, flow travel time, land use, distance to channel, and contributing area, requiring an optimization approach of the type introduced here. A Pareto frontier describing the trade-off between the number of BMPs, representing project cost, and watershed flooding was developed. Journal of Water Resources Planning and Management © ASCE. 1971 Probabilistic nonlinear prediction of river flows Tamea S., Laio F. and Ridolfi L. Water Resources Research 2005 41/9 (1-9) [1] In the recent past the nonlinear prediction (NLP) method, initially developed in the context of nonlinear time series analysis, has been successfully applied to river flow deterministic forecasting. In this work a probabilistic approach to the NLP method is proposed, which allows one to estimate the probability distribution of the predicted discharge values and to quantify the total uncertainty related to the forecast. An ensemble technique is also proposed in order to optimize the choice of the parameter values and to provide robustness to the model calibration. The probabilistic NLP method is applied to a river flow time series, giving results that confirm the effectiveness and reliability of the proposed approach. Copyright 2005 by the American Geophysical Union. 1972 A Markov switching model for annual hydrologic time series Akintuˇg B. and Rasmussen P.F. Water Resources Research 2005 41/9 (1-10) [1] This paper investigates the properties of Markov switching (MS) models (also known as hidden Markov models) for generating annual time series. This type of model has been used in a number of recent studies in the water resources literature. The model considered here assumes that climate is switching between M states and that the state sequence can be described by a Markov chain. Observations are assumed to be drawn from a normal distribution whose parameters depend on the state variable. We present the stochastic properties of this class of models along with procedures for model identification and parameter estimation. Although, at a first glance, MS models appear to be quite different from ARMA models, we show that it is possible to find an ARMA model that has the same autocorrelation function and the same marginal distribution as any given MS model. Hence, despite the difference in model structure, there are strong similarities between MS and ARMA models. MS and ARMA models are applied to the time series of mean annual discharge of the Niagara River. Although it is difficult to draw any general conclusion from a single case study, it appears that MS models (and ARMA models derived from MS models) generally have stronger autocorrelation at higher lags than ARMA models estimated by conventional maximum likelihood. This may be an important property if the purpose of the study is the analysis of multiyear droughts. Copyright 2005 by the American Geophysical Union. 1973 Simulation of flood flow in a river system using artificial neural networks Shrestha R.R., Theobald S. and Nestmann F. Hydrology and Earth System Sciences 2005 9/4 (313-321) Artificial neural networks (ANNs) provide a quick and flexible means of developing flood flow simulation models. An important criterion for the wider applicability of the ANNs is the ability to generalise the events outside the range of training data sets. With respect to flood flow simulation, the ability to extrapolate beyond the range of calibrated data sets is of crucial importance. This study explores methods for improving generalisation of the ANNs using three different flood events data sets from the Neckar River in Germany. An ANN-based model is formulated to simulate flows at certain locations in the river reach, based on the flows at upstream locations. Network training data sets consist of time series of flows from observation stations. Simulated flows from a one-dimensional hydrodynamic numerical model are integrated for network training and validation, at a river section where no measurements are available. Network structures with different activation functions are considered for improving generalisation. The training algorithm involved back- HYDROLOGY propagation with the Levenberg-Marquardt approximation. The ability of the trained networks to extrapolate is assessed using flow data beyond the range of the training data sets. The results of this study indicate that the ANN in a suitable configuration can extend forecasting capability to a certain extent beyond the range of calibrated data sets. © EGU. 1974 Precipitation forecasts and their uncertainty as input into hydrological models Kobold M. and Suˇselj K. Hydrology and Earth System Sciences 2005 9/4 (322-332) Torrential streams and fast runoff are characteristic of most Slovenian rivers and extensive damage is caused almost every year by rainstorms affecting different regions of Slovenia. Rainfallrunoff models which are tools for runoff calculation can be used for flood forecasting. In Slovenia, the lag time between rainfall and runoff is only a few hours and on-line data are used only for now-casting. Predicted precipitation is necessary in flood forecasting some days ahead. The ECMWF (European Centre for Medium-Range Weather Forecasts) model gives general forecasts several days ahead while more detailed precipitation data with the ALADIN/SI model are available for two days ahead. Combining the weather forecasts with the information on catchment conditions and a hydrological forecasting model can give advance warning of potential flooding notwithstanding a certain degree of uncertainty in using precipitation forecasts based on meteorological models. Analysis of the sensitivity of the hydrological model to the rainfall error has shown that the deviation in runoff is much larger than the rainfall deviation. Therefore, verification of predicted precipitation for large precipitation events was performed with the ECMWF model. Measured precipitation data were interpolated on a regular grid and compared with the results from the ECMWF model. The deviation in predicted precipitation from interpolated measurements is shown with the model bias resulting from the inability of the model to predict the precipitation correctly and a bias for horizontal resolution of the model and natural variability of precipitation. © EGU. 1975 Coupling meteorological and hydrological models for flood forecasting Bartholmes J. and Todini E. Hydrology and Earth System Sciences 2005 9/4 (333-346) This paper deals with the problem of analysing the coupling of meteorological meso-scale quantitative precipitation forecasts with distributed rainfall-runoff models to extend the forecasting horizon. Traditionally, semi-distributed rainfall-runoff models have been used for real time flood forecasting. More recently, increased computer capabilities allow the utilisation of distributed hydrological models with mesh sizes from tenths of metres to a few kilometres. On the other hand, meteorological models, providing the quantitative precipitation forecast, tend to produce average values on meshes ranging from slightly less than 10 to 200 kilometres. Therefore, to improve the quality of flood forecasts, the effects of coupling the meteorological and the hydrological models at different scales were analysed. A distributed hydrological model (TOPKAPI) was developed and calibrated using a 1 1 km mesh for the case of the river Po closed at Ponte Spessa (catchment area c. 37 000 km2 ). The model was then coupled with several other European meteorological models ranging from the Limited Area Models (provided by DMI and DWD) with resolutions from 0.0625°0.0625°, to the ECMWF ensemble predictions with a resolution of 1.85°1.85°. Interesting results, describing the coupled model behaviour, are available for a meteorological extreme event in Northern Italy (Nov. 1994). The results demonstrate the poor reliability of the quantitative precipitation forecasts produced by meteorological models presently available; this is not resolved using the Ensemble Forecasting technique, when compared with results obtainable with measured rainfall. © EGU. 1976 Flood forecasting using a fully distributed model: Application of the TOPKAPI model to the Upper Xixian Catchment Liu Z., Martina M.L.V. and Todini E. Hydrology and Earth System Sciences 2005 9/4 (347-364) TOPKAPI is a physically-based, fully distributed hydrological model with a simple and parsimonious parameterisation. The 377 original TOPKAPI is structured around five modules that represent evapotranspiration, snowmelt, soil water, surface water and channel water, respectively. Percolation to deep soil layers was ignored in the old version of the TOPKAPI model since it was not important in the basins to which the model was originally applied. Based on published literature, this study developed a new version of the TOPKAPI model, in which the new modules of interception, infiltration, percolation, groundwater flow and lake/ reservoir routing are included. This paper presents an application study that makes a first attempt to derive information from public domains through the internet on the topography, soil and land use types for a case study Chinese catchment - the Upper Xixian catchment in Huaihe River with an area of about 10 000 km2 , and apply a new version of TOPKAPI to the catchment for flood simulation. A model parameter value adjustment was performed using six months of the 1998 dataset. Calibration did not use a curve fitting process, but was chiefly based upon moderate variations of parameter values from those estimated on physical grounds, as is common in traditional calibration. The hydrometeorological dataset of 2002 was then used to validate the model, both against the outlet discharge as well as at an internal gauging station. Finally, to complete the model performance analysis, parameter uncertainty and its effects on predictive uncertainty were also assessed by estimating a posterior parameter probability density via Bayesian inference. © EGU. 1977 Flood forecasting using medium-range probabilistic weather prediction Gouweleeuw B.T., Thielen J., Franchello G. et al. Hydrology and Earth System Sciences 2005 9/4 (365-380) Following the developments in short- and medium-range weather forecasting over the last decade, operational flood forecasting also appears to show a shift from a so-called single solution or ‘best guess’ deterministic approach towards a probabilistic approach based on ensemble techniques. While this probabilistic approach is now more or less common practice and well established in the meteorological community, operational flood forecasters have only started to look for ways to interpret and mitigate for end-users the prediction products obtained by combining socalled Ensemble Prediction Systems (EPS) of Numerical Weather Prediction (NWP) models with rainfall-runoff models. This paper presents initial results obtained by combining deterministic and EPS hindcasts of the global NWP model of the European Centre for Medium-Range Weather Forecasts (ECMWF) with the large-scale hydrological model LISFLOOD for two historic flood events: the river Meuse flood in January 1995 and the river Odra flood in July 1997. In addition, a possible way to interpret the obtained ensemble based stream flow prediction is proposed. © EGU. 1978 Cascading model uncertainty from medium range weather forecasts (10 days) through a rainfall-runoff model to flood inundation predictions within the European Flood Forecasting System (EFFS) Pappenberger F., Beven K.J., Hunter N.M. et al. Hydrology and Earth System Sciences 2005 9/4 (381-393) The political pressure on the scientific community to provide medium to long term flood forecasts has increased in the light of recent flooding events in Europe. Such demands can be met by a system consisting of three different model components (weather forecast, rainfall-runoff forecast and flood inundation forecast) which are all liable to considerable uncertainty in the input, output and model parameters. Thus, an understanding of cascaded uncertainties is a necessary requirement to provide robust predictions. In this paper, 10-day ahead rainfall forecasts, consisting of one deterministic, one control and 50 ensemble forecasts, are fed into a rainfall-runoff model (LisFlood) for which parameter uncertainty is represented by six different parameter sets identified through a Generalised Likelihood Uncertainty Estimation (GLUE) analysis and functional hydrograph classification. The runoff of these 52 6 realisations form the input to a flood inundation model (LisFlood-FP) which acknowledges uncertainty by utilising ten different sets of roughness coefficients identified using the same GLUE methodology. Likelihood measures for each parameter set computed on historical data are used to give uncertain predictions of flow hydrographs as well as spatial 378 HYDROLOGY inundation extent. This analysis demonstrates that a full uncertainty analysis of such an integrated system is limited mainly by computer power as well as by how well the rainfall predictions represent potential future conditions. However, these restrictions may be overcome or lessened in the future and this paper establishes a computationally feasible methodological approach to the uncertainty cascade problem. © EGU. 1979 Assessing the performance of eight real-time updating models and procedures for the Brosna River Goswami M., O’Connor K.M., Bhattarai K.P. and Shamseldin A.Y. Hydrology and Earth System Sciences 2005 9/4 (394-411) The flow forecasting performance of eight updating models, incorporated in the Galway River Flow Modelling and Forecasting System (GFMFS), was assessed using daily data (rainfall, evaporation and discharge) of the Irish Brosna catchment (1207 km2 ), considering their one to six days lead-time discharge forecasts. The Perfect Forecast of Input over the Forecast Lead-time scenario was adopted, where required, in place of actual rainfall forecasts. The eight updating models were: (i) the standard linear Auto-Regressive (AR) model, applied to the forecast errors (residuals) of a simulation (non-updating) rainfall-runoff model; (ii) the Neural Network Updating (NNU) model, also using such residuals as input; (iii) the Linear Transfer Function (LTF) model, applied to the simulated and the recently observed discharges; (iv) the Non-linear Auto-Regressive eXogenous-Input Model (NARXM), also a neural network-type structure, but having wide options of using recently observed values of one or more of the three data series, together with non-updated simulated outflows, as inputs; (v) the Parametric Simple Linear Model (PSLM), of LTF-type, using recent rainfall and observed discharge data; (vi) the Parametric Linear perturbation Model (PLPM), also of LTF-type, using recent rainfall and observed discharge data, (vii) n-AR, an AR model applied to the observed discharge series only, as a naive updating model; and (viii) nNARXM, a na¨ıve form of the NARXM, using only the observed discharge data, excluding exogenous inputs. The five GFMFS simulation (non-updating) models used were the non-parametric and parametric forms of the Simple Linear Model and of the Linear Perturbation Model, the Linearly-Varying Gain Factor Model, the Artificial Neural Network Model, and the conceptual Soil Moisture Accounting and Routing (SMAR) model. As the SMAR model performance was found to be the best among these models, in terms of the Nash-Sutcliffe R2 value, both in calibration and in verification, the simulated outflows of this model only were selected for the subsequent exercise of producing updated discharge forecasts. All the eight forms of updating models for producing lead-time discharge forecasts were found to be capable of producing relatively good lead-1 (1-day ahead) forecasts, with R2 values almost 90% or above. However, for higher lead time forecasts, only three updating models, viz., NARXM, LTF, and NNU, were found to be suitable, with lead-6 values of R2 about 90% or higher. Graphical comparisons were made of the leadtime forecasts for the two largest floods, one in the calibration period and the other in the verification period. © EGU. 1980 Utility of different data types for calibrating flood inundation models within a GLUE framework Hunter N.M., Bates P.D., Horritt M.S. et al. Hydrology and Earth System Sciences 2005 9/4 (412-430) To translate a point hydrograph forecast into products for use by environmental agencies and civil protection authorities, a hydraulic model is necessary. Typical one- and two-dimensional hydraulic models are able to predict dynamically varying inundation extent, water depth and velocity for river and floodplain reaches up to 100 km in length. However, because of uncertainties over appropriate surface friction parameters, calibration of hydraulic models against observed data is a necessity. The value of different types of data is explored in constraining the predictions of a simple two-dimensional hydraulic model, LISFLOOD-FP. For the January 1995 flooding on the River Meuse, The Netherlands, a flow observation data set has been assembled for the 35-km reach between Borgharen and Maaseik, consisting of Synthetic Aperture Radar and air photo images of inundation extent, downstream stage and discharge hydrographs, two stage hydrographs internal to the model domain and 84 point observations of maximum free surface elevation. The data set thus contains examples of all the types of data that potentially can be used to calibrate flood inundation models. 500 realisations of the model have been conducted with different friction parameterisations and the performance of each realisation has been evaluated against each observed data set. Implementation of the Generalised Likelihood Uncertainty Estimation (GLUE) methodology is then used to determine the value of each data set in constraining the model predictions as well as the reduction in parameter uncertainty resulting from the updating of generalised likelihoods based on multiple data sources. © EGU. 1981 An empirical method for estimating future flood risks for flood warnings Hlavcova K., Kohnova S., Kubes R. et al. Hydrology and Earth System Sciences 2005 9/4 (431-448) Since medium and long-term precipitation forecasts are still not reliable enough, rough estimates of the degree of the extremity of forthcoming flood events that might occur in the course of dangerous meteorological situations approaching a basin could be useful to decision-makers as additional information for flood warnings. One approach to answering such a problem is to use real-time data on the soil moisture conditions in a catchment in conjunction with estimates of the extremity of the future rainfall and experience with the basin’s behaviour during historical floods. A scenario-based method is proposed for such a future flood risk estimation, based on an a priori evaluation of the extremity of hypothetical floods generated by combinations of synthetic extreme precipitation and previously observed antecedent pre-flood basin saturations. The Hron river basin, located in central Slovakia, was chosen as the pilot basin in the case study. A time series of the basin’s average daily precipitation was derived using spatial interpolation techniques. A lumped HBV-type daily conceptual rainfall-runoff model was adopted for modelling runoff. Analysis of the relationship of the modelled historical pre-flood soil moisture and flood causing-precipitation revealed the independence of both quantities for rainfall durations lasting 1 to 5 days. The basin’s average annual maximum 1 to 5 day precipitation depths were analysed statistically and synthetic extreme precipitation scenarios associated with rainfall depths with return periods of 5, 20, 50 and 100 years, durations of 1 to 5 days and temporal distribution of extreme rainfall observed in the past were set up for runoff simulation. Using event-based flood simulations, synthetic flood waves were generated for random combinations of the rainfall scenarios and historical pre-flood soil moisture conditions. The effect of any antecedent basin saturation on the extremity of floods was quantified empirically and critical values of the basin saturation leading to floods with a higher return period than the return period of precipitation were identified. A method for implementing such critical values into flood risk warnings in a hydrological forecasting and warning system in the basin was suggested. © EGU. 1982 Operational hydro-meteorological warning and realtime flood forecasting: The Piemonte Region case study Rabuffetti D. and Barbero S. Hydrology and Earth System Sciences 2005 9/4 (457-466) The development and implementation of a real-time flood forecasting system in the context of the Piemonte Region’s hydrometeorological operational alert procedure is described. The area of interest is the Upper Po River basin (north-west Italy) of approximately 37 000 km2 and its river network of about 3000 km and three big lakes. FloodWatch, a GIS-based decision support system for real-time flood forecasting, has been developed and used operationally at the Piemonte Region’s Room for the Situation of Natural Hazards in Torino, Italy, since January 2000. The system is linked directly to the telemetric gauges system, uses daily quantitative precipitation and temperature forecasts issued by the Regional Meteorological Service and automatically supplies operational forecasts of water-level and discharge at about 30 locations for up to 48 hours. Strengths and limits of the system and its link with operational flood alert and management are discussed. The case study presented is the October 2000 flood event, when the north-west of Italy experienced one of the largest floods on record. Results highlight how the uncertainty linked to the use of meteorological forecasts greatly influences the quality of the hydrological forecasts. The proposed alert HYDROLOGY procedure, based on coded risk levels, can help effectively in facing forecast uncertainties. © EGU. 1983 A comparison of regionalisation methods for catchment model parameters Parajka J., Merz R. and Bl¨oschl G. Hydrology and Earth System Sciences 2005 9/3 (157-171) In this study we examine the relative performance of a range of methods for transposing catchment model parameters to ungauged catchments. We calibrate 11 parameters of a semi-distributed conceptual rainfall-runoff model to daily runoff and snow cover data of 320 Austrian catchments in the period 1987-1997 and verify the model for the period 1976-1986. We evaluate the predictive accuracy of the regionalisation methods by jack-knife cross-validation against daily runoff and snow cover data. The results indicate that two methods perform best. The first is a kriging approach where the model parameters are regionalised independently from each other based on their spatial correlation. The second is a similarity approach where the complete set of model parameters is transposed from a donor catchment that is most similar in terms of its physiographic attributes (mean catchment elevation, stream network density, lake index, areal proportion of porous aquifers, land use, soils and geology). For the calibration period, the median Nash-Sutcliffe model efficiency ME of daily runoff is 0.67 for both methods as compared to ME=0.72 for the at-site simulations. For the verification period, the corresponding efficiencies are 0.62 and 0.66. All regionalisation methods perform similar in terms of simulating snow cover. © 2005 Author(s). This work is licensed under a Creative Commons License. 1984 Soil moisture-runoff relation at the catchment scale as observed with coarse resolution microwave remote sensing Scipal K., Scheffler C. and Wagner W. Hydrology and Earth System Sciences 2005 9/3 (173-183) Microwave remote sensing offers emerging capabilities to monitor global hydrological processes. Instruments like the two dedicated soil moisture missions SMOS and HYDROS or the Advanced Scatterometer onboard METOP will provide a flow of coarse resolution microwave data, suited for macro-scale applications. Only recently, the scatterometer onboard of the European Remote Sensing Satellite, which is the precursor instrument of the Advanced Scatterometer, has been used successfully to derive soil moisture information at global scale with a spatial resolution of 50 km. Concepts of how to integrate macroscale soil moisture data in hydrologic models are however still vague. In fact, the coarse resolution of the data provided by microwave radiometers and scatterometers is often considered to impede hydrological applications. Nevertheless, even if most hydrologic models are run at much finer scales, radiometers and scatterometers allow monitoring of atmosphere-induced changes in regional soil moisture patterns. This may prove to be valuable information for modelling hydrological processes in large river basins (>10 000 km2 ). In this paper, ERS scatterometer derived soil moisture products are compared to measured runoff of the Zambezi River in south-eastern Africa for several years (1992-2000). This comparison serves as one of the first demonstrations that there is hydrologic relevant information in coarse resolution satellite data. The observed high correlations between basin-averaged soil moisture and runoff time series (R2 >0.85) demonstrate that the seasonal change from low runoff during the dry season to high runoff during the wet season is well captured by the ERS scatterometer. It can be expected that the high correlations are to a certain degree predetermined by the pronounced inter-annual cycle observed in the discharge behaviour of the Zambezi. To quantify this effect, time series of anomalies have been compared. This analysis showed that differences in runoff from year to year could, to some extent, be explained by soil moisture anomalies. © 2005 Author(s). This work is licensed under a Creative Commons License. 1985 Using a spatio-temporal dynamic state-space model with the EM algorithm to patch gaps in daily riverflow series Amisigo B.A. and van de Giesen N.C. Hydrology and Earth System Sciences 2005 9/3 (209-224) A spatio-temporal linear dynamic model has been developed for patching short gaps in daily river runoff series. The model 379 was cast in a state-space form in which the state variable was estimated using the Kalman smoother (RTS smoother). The EM algorithm was used to concurrently estimate both parameter and missing runoff values. Application of the model to daily runoff series in the Volta Basin of West Africa showed that the model was capable of providing good estimates of missing runoff values at a gauging station from the remaining time series at the station and at spatially correlated stations in the same sub-basin. © 2005 Author(s). This work is licensed under a Creative Commons License. 1986 PAI-OFF: A new strategy of flash-flood forecasting in quickly responding catchments (German) (PAI-OFF: Eine neue Strategie zur Hochwasservorhersage in schnell reagierenden Einzugsgebieten) Schmitz G.H., Cullmann J., G¨orner W. et al. Hydrologie und Wasserbewirtschaftung 2005 49/5 (226-234) PAI-OFF (Process Modelling and Artificial Intelligence for Online Flood Forecasting) combines the reliability of physically based, sophisticated modelling with the operational advantages of Artificial Neural Networks (ANN), i.e. low computation times and robustness, which form the basic requirements for flash-flood forecasting. After presenting the theory of the new methodology, the results of a catchment related meteorological analysis for generating storm scenarios serve as the input to a coupled hydrologic/hydraulic model which is set up for a mountainous catchment in East Germany. Operating on this basis, the catchment model for all realistically possible combinations of flood formation builds a data bank consisting of corresponding input/output vectors. We complete the data bank for training the ANN by adding yet more flood relevant data for characterizing the hydrological and meteorological catchment situation prior to a storm event. After training different ANN, a competitive analysis of four different network architectures provides insight in their problem-specific performances. After this preparatory step, the selected ANN is applied for online flash-flood forecasting in the considered catchment, using an "unseen" storm event, i.e. one which did not feature in the training process. The convincing agreement between the predicted and observed flood hydrographs underlines the application potential of the new PAIOFF methodology for online flood forecasting even in smaller catchments. 1987 Long-term behaviour of low-flow parameters at gauges of the Havel and Elbe river basins (German) (Langzeitverhalten von Niedrigwasserkenngr¨oßen von Pegeln des Havelgebietes und der Elbe) Finke W. and Krause S. Hydrologie und Wasserbewirtschaftung 2005 49/5 (248-254) Long time-series of streamflow indicate influences of climate variations, land-use changes, water uses, and water-management activities. In a comparison of streamflow data, the influences are particularly intensive in the low-flow range, and they find their reflection in low-flow parameters rather than in data measured during flood-flow. For selected gauges on the River Elbe and in the Havel river basin, long time-series of low-flow parameters were examined for their long-term behaviour. This paper presents the results of this comparative regional study. 1988 Statistical calculation of rainfall for various return periods using the L-moment method (Spanish) (C´alculo estadstico de lluvias para diversos perodos de retorno por el m´etodo de los momentos-L) Comas F.M. Tecnologia del Agua 2005 25/264 (68-72) Statistical estimates of rainfall traditionally employed Gumbel’s law. However, over the course of time it was realised that the records of many weather stations did not comply with this law. New calculation methods were put forward and regionally based methods eventually established themselves. This paper presents a new regional method for defining maximum rainfall for a given return period, based on so-called L-moments, which is more accurate. This method has also developed processes for assessing the heterogeneity of a given region and goodness of fit, and software has been produced for performing the calculations. It was found that in the case of the river Francol, there was a matching fit with the method of weighted positioning of the centre of gravity of the sample in the L-asymmetry, L-Kurtosis plane. 380 HYDROLOGY 1989 An operational flash-flood forecasting chain applied to the test cases of the EU project HYDROPTIMET Taramasso A.C., Gabellani S. and Parodi A. Natural Hazards and Earth System Science 2005 5/5 (703-710) The application of a flash-flood prediction chain, developed by CIMA, to some testcases for the Tanaro river basin in the framework of the EU project HYDROPTIMET is presented here. The components of the CIMA chain are: forecast rainfall depths, a stochastic downscaling procedure and a hydrological model. Different meteorological Limited Area Models (LAMs) provide the rainfall input to the hydrological component. The flashflood prediction chain is run both in a deterministic and in a probabilistic configuration. The sensitivity of forecasting chain performances to different LAMs providing rainfall forecasts is discussed. The results of the application show how the probabilistic forecasting system can give, especially in the case of convective events, a valuable contribution in addressing the uncertainty at different spatio-temporal scales involved in the flash flood forecasting problem in small and medium basins with complex orography. © 2005 Author(s). This work is licensed under a Creative Commons License. 1990 The 8 and 9 September 2002 flash flood event in Fance: A model intercomparison Anquetin S., Yates E., Ducrocq V. et al. Natural Hazards and Earth System Science 2005 5/5 (741-754) Within the framework of the European Interreg IIIb Medocc program, the HYDROPTIMET project aims at the optimization of the hydrometeorological forecasting tools in the context of intense precipitation within complex topography. Therefore, some meteorological forecast models and hydrological models were tested on four Mediterranean flash-flood events. One of them occured in France where the South-eastern ridge of the French "Massif Central", the Gard region, experienced a devastating flood on 8 and 9 September 2002. 24 people were killed during this event and the economic damage was estimated at 1.2 billion euros. To built the next generation of the hydrometeorological forecast ing chain that will be able to capture such localized and fast events and the resulting discharges, the forecasted rain fields might be improved to be relevant for hydrological purposes. In such context, this paper p resents the results of the evaluation methodology proposed by Yates et al. (2005) that highlights the relevant hydrological scales of a simulated rain field. Simulated rain fields of 7 meteorological model runs concerning with the French event are therefore evaluated for different accumulation times. The dynamics of these models are either based on nonhydrostatic or hydrostatic equation systems. Moreover, these models were run under different configurations (resolution, initial conditions). The classical score analysis and the areal evaluation of the simulated rain fields are then performed in order to put forward the main simulation characteristics that improve the quantitative precipitation forecast. The conclusions draw some reco mmendations on the value of the quantitative precipitation forecasts ad way to use it for quantitative discharge forecasts within mountainous areas. © 2005 Author(s). This work is licensed under a Creative Commons License. 1991 The behaviour of a hydrologic system under a Mediterranean climate using correlation and spectral analysis of the water discharge and runoff. Case of three south Mediterranean basins: (Sebdou, Mouilah and Isser wadis - Tafna - Algeria) (French) (Le comportement d’un syst`eme hydrologique en climat m´editerran´een par l’analyse corr´elatoire et spectrale des d´ebits et des pluies. Cas de trois sous bassins sud-M´editerran´eens: (oued Sebdou, Moulah et Isser - Tafna NW Alg´erie)) Bouanani A., Baba Hamed K., Mania J. and Bensalah M. Revue des Sciences de l’Eau 2005 18/2 (215-224) The aim of this work was to show that correlation and spectral analyses can be used to understand the functioning of hydrological systems. Accordingly, a study was carried out on three southern Mediterranean basins: Sebdou; Mouilah and Isser; located in the north western of Algeria (figure 1). Correlation and spectral analyses of daily rainfall and discharge rates for one hydrological cycle were carried out. Simple analysis Simple analysis of rainfall showed that the correlogram s (figure 2) decreased rapidly for the three basins, reaching a value of 0.2 within 1- 2 days. This result indicated that rainfall was a quasi-random phenomenon. The variance density spectrum (figure 3) showed that the rainfall distribution was not monotonous and presented a "Leigh" signal structure. The simple analysis of discharge rates indicated that the Sebdou system was different. The correlogram (figure 4a) decreased quicky, characterising independent events without memory and with non-significant amounts of water. However, the Mouilah and Isser correlograms (figure 4 b, c) decreased slowly. They represent important memory effects with regulation of significant amounts of water. The spectral band (figure 5) confirmed that the Sebdou system did not modify the input information. The regulation time was about 5 d for Sebdou, 21 and 43 d respectively for Mouilah and Isser. Cross analysis The cor relograms (figure 6) show that the Mouilah and Isser rivers have a great buffering ability. The Sebdou River was characterised by a composite response of the surface flow and an important groundwater flow. The amplitude function (figure 7) indicated that the Sebdou system had good inertia. The lag time (figure 8) was 9, 2 and 5 days respectively for the Sebdou, Mouilah and Isser rivers. The amplification and attenuation of the input signal (figure 10) show that the Sebdou basin is the most karstified system. The non-linearity of the relationship between rainfall and discharge was expressed by the coherence coefficient (figure 9), which was lower than 1. 1992 Peak discharge and time to peak scaling in urban runoff modeling (French) (Effet d’´echelle sur la simulation du ruissellement en milieu urbain) Kamal A. and Bennis S. Revue des Sciences de l’Eau 2005 18/2 (225-246) It is possible to simulate the hydraulic functioning of a given network either it is with a detailed "microscopic" model at the street section scale or with a global "macroscopic" model which generates total flow rated at the outlet of a basin. The microscopic model is useful when one is concerned with the hydraulic performance of individual conduit sections and the precise locations of problematic areas within a network. Macroscopic modeling is mainly useful when one is interested exclusively by the exit flow rates of a basin. This may be the case in interceptor management where the flow rate is a parameter of the global optimization procedure, within the framework of real time management of regulators. In this case, detailed modeling of a network is unnecessary. On the other hand, detailed modeling requires that a voluminous data base be built and maintained, implying expenditures exceeding the resources of small municipalities. The present work consists in elabora ting a systematic method which allows one to substitute simplified hydraulic modeling for detailed modeling of a drainage network. The approach is based on the analysis of the drainage parameters in an urban environment. The non-dimensional groupings retained in this analysis comprise the characteristics a of the basin, of the network and of rainfall. In order to provide a greater generality to this approach, the authors applied the analysis to synthetic networks and rainfalls covering a wide range of specific cases. From a practical viewpoint, the objective was to link the peak f low rates and the time to peak of the global model to those of the detailed model of a basin. Two transfer functions have thus been proposed in order to obtain the peak flow rate and the time to peak of the detailed model as functions of the same parameters provided by the global model. The parameters retained for the transfer function are the density of the drainage network and the rate of filling of the network. In order to im plement the proposed method and perform the required hydraulic and hydrological simulations, the authors have used the SWMM program (Storm Water Management Model). 180 simulations have thus been completed, 15 for each type of network and for each type of rainfall. For every combination, one computes the peak flow rate and the time to peak as obtained by the global and detailed models of the basin. The pr oposed multi-criterion analysis revealed that the total discrepancy between simplified and detailed modeling of a drainage network is very important. Within the range of the assumed densities, the difference can be as great as 50%. This discrepancy between global and detailed modeling is explained by the storage capacity of the different types of networks. Indeed, for a same given drained area, a network provides additional storage with increasing length of the network and therefore with increasing drainage density. On the basis of the above finding, a HYDROLOGY global model cannot replace a detailed model without the use of required corrections for the computation of peak flow rates for a given specific case. In order to resolve this difficulty, it is recommended to use the empirical models proposed herein to reduce the discrepancy and thereby obtain the appropriate corrections. The proposed method has been subjected to a validation program on basin No.1 of the Verdun borough. Agreement between the flow rates measured at the entrance of the Rh´eaume pumping station and those simulated by the proposed method is very satisfactory. The transformation models derived from the analysis allow for the transition from a global model to a detailed one and provide a significant improvement in optimized real time management of drainage networks. 1993 Hydroclimatology of the Nile: Results from a regional climate model Mohamed Y.A., van den Hurk B.J.J.M., Savenije H.H.G. and Bastiaanssen W.G.M. Hydrology and Earth System Sciences 2005 9/3 (263-278) This paper presents the result of the regional coupled climatic and hydrologic model of the Nile Basin. For the first time the interaction between the climatic processes and the hydrological processes on the land surface have been fully coupled. The hydrological model is driven by the rainfall and the energy available for evaporation generated in the climate model, and the runoff generated in the catchment is again routed over the wetlands of the Nile to supply moisture for atmospheric feedback. The results obtained are quite satisfactory given the extremely low runoff coefficients in the catchment. The paper presents the validation results over the sub-basins: Blue Nile, White Nile, Atbara river, the Sudd swamps, and the Main Nile for the period 1995 to 2000. Observational datasets were used to evaluate the model results including radiation, precipitation, runoff and evaporation data. The evaporation data were derived from satellite images over a major part of the Upper Nile. Limitations in both the observational data and the model are discussed. It is concluded that the model provides a sound representation of the regional water cycle over the Nile. The sources of atmospheric moisture to the basin, and location of convergence/divergence fields could be accurately illustrated. The model is used to describe the regional water cycle in the Nile basin in terms of atmospheric fluxes, land surface fluxes and land surface-climate feedbacks. The monthly moisture recycling ratio (i.e. locally generated/total precipitation) over the Nile varies between 8 and 14%, with an annual mean of 11%, which implies that 89% of the Nile water resources originates from outside the basin physical boundaries. The monthly precipitation efficiency varies between 12 and 53%, and the annual mean is 28%. The mean annual result of the Nile regional water cycle is compared to that of the Amazon and the Mississippi basins. © 2005 Author(s). This work is licensed under a Creative Commons License. 1994 Regional streamflow estimation by standard regional dependence function approach ¨ Altunkaynak A., Ozger M. and S¸en Z. Journal of Hydraulic Engineering 2005 131/11 (1001-1006) The main purpose of this paper is to propose a standard regional dependence function (SRDF) based on concepts of semivariogram and especially point cumulative semivariogram for regional streamflow estimation. The SRDFs are obtained from available spatial data and show regional dependence, which decreases with distance from a given site. These functions present quantitatively the regional dependence of the streamflow phenomenon recorded at irregular sites over a drainage basin and provide a unique opportunity for the establishment of regional objective estimation method based on weighed averages. The weightings are obtained by means of the SRDF given the distance between any two sites. The implementation of the proposed methodology is presented for some streamflow records from the Lower and Upper Mississippi River watershed in the United States. For the application, the experimental SRDF forms are first obtained from the available data, and these are then employed directly in the regional estimation procedure. The study indicated that the use of all the stations in a region for the estimation at any particular station is rather na¨ıve because far away stations (more than 1,000 km away) are taken into consideration. The final conclusion is that discharge at any particular station is better described as 381 a function of discharge at several (3-5) closest stations. The reliability of the method is measured through the cross validation procedure, and it is observed that the procedure yields streamflow predictions with less than 10% relative error. Journal of Hydraulic Engineering © ASCE. 1995 Magnification of flood disasters and its relation to regional precipitation and local human activities since the 1980s in Xinjiang, northwestern China Fengqing J., Cheng Z., Guijin M. et al. Natural Hazards 2005 36/3 (307-330) Analyses of flood disasters were conducted using 1950-2001 data on the flood-damaged areas of cropland, the annual number of flood disasters and the direct economic losses in Xinjiang. There is an increasing trend in flood disasters in Xinjiang during the second half of the 20th century, especially since the mid1980s. Results of a non-parametric Mann-Kendall test on the cropland-flooded index time series revealed an abrupt change in the mid-1980s. The reasons are discussed with respect to changes in annual precipitation and regional human activities, by correlating cropland-flooded area to annual precipitation and three socio-economic parameters (population, cropland area and GDP). The correlation coefficients between the flood-damaged area and the annual precipitation during the periods 1961-1998 and 1987-1998 were substantially higher than during the period of 1961-1986. The correlation coefficients between the flooddamaged area and the three human activity parameters, however, were relatively high for the whole period of 1961-1998, but generally not significant for the 1961-1986 and 1987-1998 periods, separately. These suggest that the occurrence of flood disasters could be mainly induced by local human activities before the mid-1980s, and thereafter mainly by abnormal precipitation in Xinjiang. Meteorological and hydrological records showed that the number of heavy rainfall events and the frequency of rainstorm flood disasters increased since the 1980s. In addition, siltation of reservoirs and loss of flood control structures are partly responsible for the increase of flood-damaged area. These results suggest that the increasing trend in flood disasters in Xinjiang since the middle 1980s could be attributed, at least in part, to an increasing trend in annual precipitation. © Springer 2005. 1996 Hydrological cycle in the upper Mississippi River basin: 20th century simulations by multiple GCMs Takle E.S., Jha M. and Anderson C.J. Geophysical Research Letters 2005 32/18 (1-5) We used 20th century simulations by nine global climate models (GCMs) to provide input for a streamflow model to simulate baseline hydrologic conditions in the Upper Mississippi River Basin (UMRB). Statistical tests revealed that streamflow data produced by members of the GCM multi-model ensemble were serially uncorrelated at all lags and formed unimodal distributions and that GCM multimodel results may be used to assess annual streamflow in the UMRB. Although all low-resolution GCMs produced large differences from observations of streamflow and hydrological components simulated by the streamflow model, the nine-member ensemble performed quite well. Results of statistical tests indicate that, of all models used, the high-resolution GCM - the only high-resolution model tested - gives simulated streamflows much closer to observed values, despite the fact that its low-resolution sister model has no advantage over the other seven low-resolution models. Copyright 2005 by the American Geophysical Union. 1997 Evaluation of the synthetic annual maximum storms Saf B. Journal of Environmental Hydrology 2005 13/- (11p) Long term historical records of hydrological information such as rainfall and runoff data form the basis of planning and design of major water resources projects. However, in most cases such historical records are unavailable, and in situations where they are available, the records are too short to have any statistically significant meaning. One approach that has been adopted to overcome this difficulty is to generate long-term data synthetically. In this study, the outcome of an attempt to generate synthetic rainfall data is presented. The Monte Carlo method is used, which is an experimental statistical method in generating samples for solving some probability problems as old as probability theory itself. In 382 HYDROLOGY this study, synthetic annual maximum storms distributed as Type1Extremal (or Gumbel) with random effective durations and specific time distribution for given population mean and variance are generated using the method. Effective durations of the synthetic annual maximum storms are related to the basin characteristics, length (L) and harmonic slope (S) of the main course, by Kirpich’s time of concentration relationship. After synthetic annual maximum storms are generated, sample statistics and frequency distributions of the generated annual maximum storms of random effective durations are investigated. Eight well-known probability distribution models, (Normal (N), LogNormal with two and three parameters (LN2 and LN3), Gumbel (GUM), LogGumbel (LGUM), Gamma with two and three parameters (G2 and G3), and LogPearson 3 (LP3), with moment and maximum likelihood parameters are used for synthetic storm series by chi-square and probability plot correlation goodness of fit tests. The results of the study reveal that the probability distribution of the rainfall input may even diverge from their parent (Type-I Extremal) distributions because of the sampling, and since the generated input series is a mixture of rainfall events of variable durations. 1998 Generation mechanism of woodland runoff and sediment on Loess Plateau under hypo-rainfall - A case study of artificial P. tabulaeformis and secondary natural P. dadidiana stands (Chinese) Pan C. and Shangguan Z. Chinese Journal of Applied Ecology 2005 16/9 (1597-1602) Based on the long-term observation and from the viewpoints of water balance and runoff-and sediment generation, this paper studied the generation processes of runoff and sediment on two typical woodlands, artificial P. tabulaeformis and secondary natural P. dadidiana, and uncultivated slope-land in Loess Plateau under hyporainfall. The results showed that within the range of 5.0-50.0 mm rainfall, the total interception of canopy and litter was 15.45%-56.80% for P. tabulaeformis and 20.56%-47.81% for P. dadidiana, and decreased with increasing rainfall. Woodlands had a higher soil water infiltration capacity than uncultivated slope-land, especially in 0-20 cm soil layer. Both the two woodlands did not generate runoff under regular rainfall. Under the assumed rainfall of 2.5 mmmin-1 intensity and 30 min duration, P. dadidiana stand did not produce runoff, but the runoff velocity and sediment-carrying capacity of uncultivated slope-land were 23.5 times, and runoff shearing stress and energy were 8 times as much as P. tabulaeformis stand. The runoff-and sediment generation on P. tabulaeformis stand decreased by 87.6% and 99.4%, respectively, compared with those on uncultivated slopeland, which was well accorded with the average observed value in runoff plots during 1988-2000. The theoretical analysis on the generation mechanism of woodland runoff and sediment may be effective to evaluate the benefits of forest in soil and water conservation. 1999 Construction and verification of distributed rainfallrunoff model for forested watershed in alpine and gorge region (Chinese) Liu J., Pei T., Wang A. and Yang H. Chinese Journal of Applied Ecology 2005 16/9 (1638-1644) Considering of the main hydrological characteristics in the upper Zagunao River watershed of the upper reach of Minjiang River, general hydrological models were selected to construct the distributed rainfall-runoff process model for the forested watershed in typical alpine and gorge terrains. Calibration of too many regional parameters was avoided to assure the transportability of the models in similar watersheds. Two flow series of 1 000 hours in 1999 and 2000 were simulated by using the distributed model. The runoff hydrograph, accumulative runoff volume, peak discharge, and peak time showed good fittings with observed series. The simple structure and less empirical parameters gave the distributed model the ability to simulate the rainfall-runoff processes in similar watershed across scales, which provided the basic approach to the hydrological scaling research. 2000 Application of wavelet transform to monthly runoff time serial analysis in Zagunao watershed, the upper Minjiang River (Chinese) Lin Y., Liu S., Li C. et al. Chinese Journal of Applied Ecology 2005 16/9 (1645-1649) Runoff is an important component of regional water resources, and its dynamics is to some extent an indicator of water resources dynamics in a region. To know the runoff dynamics and water resources in a region is essential for the sustainable utilization and planning of water resources, and for the research on hydrological response of vegetation change at watershed scale. To disclose the water resources dynamics in Upper Minjiang River, one of the large reaches of Yangze River in southwest China, this paper analyzed the runoff dynamic features of Zagunao watershed, an important watershed in Minjiang River basin. Multi-Resolution Analysis (MRA) and periodicity analysis were conducted with Dmey wavelet function on the monthly runoff data from 1962 to 2002 observed by Zagunao hydrological station, which provided a data-based approximation on the evolution of monthly runoff in Zagunao watershed. It was found that the runoff dynamics in Zagunao watershed was relatively stable during 1962-1978, despite that this period was just in correspondence with the term of intensive deforestation activities in Upper Minjiang River basin. It was also clear that the runofff in Zagunao watershed was increased from 1986 to 1997, which was inconsistent with the commonly accepted viewpoint that the runoff decreased with increasing vegetation cover in forest watershed. However, the increasing trend from 1986-1997 was consistent with the research results in Yichang by Wang Wensheng and with the global warming at global and continent scale, which meant that global climate change plays a big role in runoff dynamics in Upper Minjiang River. Periodicity analysis showed that the rich-short water periodicity at the scale of 10 years (120 months) and 5 years (60 months) was 3 and 7 times, respectively, which could provide invaluable information for the eco-hydrological function research of forest landscape in Minjiang river basin and the sustainable utilization of water resources. The results from the case study highlighted that sometimes, it was very necessary to consider the role of global climatic warming in disclosing the hydrological response of land use/cover change at watershed scale, otherwise, it would be difficult to explain some hydrological phenomena. 2001 Relationships between soil and water loss and landscape pattern on Loess Plateau (Chinese) Suo A., Hong J., Lin Y. and Ge J. Chinese Journal of Applied Ecology 2005 16/9 (1719-1723) Based on the theories of detrended canonical correspondence analysis (DCCA), 12 soil and water loss indices ("species") and 7 landscape indices ("environmental factors") were adopted to quantitatively analyze the effects of landscape pattern on the soil and water loss in Jinghe River basin on Loess Plateau. The results showed that the first four DCCA axes were significantly correlated to agricultural land ratio, landscape diversity index, forest land ratio, and landscape contagion index. The characteristics of soil and water loss changed obviously with landscape pattern gradient, e.g., Sanshuihe watershed with a forest cover larger than 65% and low landscape diversity had a big and stable runoff, but small sediment and low river sand content. The runoff generation coefficient and runoff depth as well as the sediment transport and river sand content increased with the increasing agricultural land ratio and landscape diversity and the decreasing forest land ratio. As for Honghe watershed with a very low forest cover but high agricultural land ratio (53.41%), and with a relatively high landscape diversity and complex landscape pattern, it had the highest river sand content and the biggest sediment transport, and its monthly runoff and sediment transport varied markedly. The soil and water loss in the Upper-Huan, Down-Huan and Dongchuan watersheds with smaller forest and agricultural land ratio and relatively simple landscape pattern was smaller than that of the watersheds with dominated agricultural land. 2002 Indoor imitation experimental study on driving factors of rainfall-runoff process Zhang S., Liu C., Xia J. et al. Science in China, Series D: Earth Sciences 2005 48/3 (417-428) The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The research results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is HYDROLOGY obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south China region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north China where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north China region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north China region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north China region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south China region and the basic theoretical research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with intensity, but has nothing to do with the ground pad. There is a negative linear relationship between intensity and time to peak. The amount of pondage capacity in a catchment is in linear relationship with intensity and peak discharge, with obvious influence by the ground pad status and interception, and it has nothing to do with the position of interceptions. Copyright by Science in China Press 2005. Channel hydraulics and sediment transport 2003 Errors of kinematic wave and diffusion wave approximations for time-independent flows with infiltration and momentum exchange included Singh V.P., Jain S.K. and Sherif M.M. Hydrological Processes 2005 19/9 (1771-1790) Error equations for kinematic wave and diffusion wave approximations were derived for time-independent flows on infiltrating planes and channels under one upstream boundary and two downstream boundary conditions: zero flow at the upstream boundary, and critical flow depth and zero depth gradient at the downstream boundary. These equations specify error in the flow hydrograph as a function of space. The diffusion wave approximation was found to be in excellent agreement with the dynamic wave approximation, with errors below 2% for values of KF (e.g. KF 75), where K is the kinematic wave number and F is the Froude number. Even for small values of KF (e.g. KF = 25), the errors were typically less than 3%. The accuracy of the diffusive approximation was greatly influenced by the downstream boundary condition. For critical flow depth downstream boundary condition, the error of the kinematic wave approximation was found to be less than 10% for KF 75 and greater than 20% for smaller values of KF. This error increased with strong downstream boundary control. The analytical solution of the diffusion wave approximation is adequate only for small values of K. Copyright © 2005 John Wiley & Sons, Ltd. 2004 A simple method to include vertical resolution in a river model, and results from an implementation Jakobsen F., Olesen K.W. and Madsen M. Nordic Hydrology 2005 36/2 (163-174) A simple method to include vertical resolution in a one-dimensional river model is outlined. The equations on which the method is based are the width-averaged continuity, momentum and transport equations. Some details are given on how to formulate the bed friction in a river model with vertical resolution. The equations are transformed to be in sigma coordinates. The numerical techniques, which make maximum use of an already implemented numerical solution technique in an existing river 383 model, are described. The method is used to implement vertical resolution in the existing river model, MIKE 11. The implementation is tested on the following cases: logarithmic velocity profile, wind driven velocity profile, rapid accelerated flow, lock exchange and finally wind-forced entrainment. All test cases showed good agreement. © IWA Publishing 2005. 2005 Changes in hydrologic regime by dams Magilligan F.J. and Nislow K.H. Geomorphology 2005 71/1-2 (61-78) Dams have major impacts on river hydrology, primarily through changes in the timing, magnitude, and frequency of low and high flows, ultimately producing a hydrologic regime differing significantly from the pre-impoundment natural flow regime. This paper presents the analysis of pre- and post-dam hydrologic changes from dams that cover the spectrum of hydrologic and climatic regimes across the United States. Our overall goals are to document the type, magnitude, and direction of hydrologic shifts because of impoundment. Using the entire database for the National Inventory of Dams (NID) for dams possessing longstanding U.S. Geological Survey (USGS) gages downstream, we identified 21 gage stations that met length-of-record criteria encompassing an array of types of dams and spanning four orders of magnitude in contributing watershed area. To assess hydrologic changes associated with dams, we applied a hydrologic model, the Indicators of Hydrologic Alteration (IHA), supplemented with orientation statistics for certain hydrograph parameters. Dams had significant impacts on the entire range of hydrologic characteristics measured by IHA. For many characteristics, the direction and significance of effects were highly consistent across the 21 sites. The most significant changes across these sites occurred in minimum and maximum flows over different durations. For low flows, the 1-day through 90-day minimum flows increased significantly following impoundment. The 1-day through 7-day maximum flows decreased significantly across the sites. At monthly scales, mean flows in April and May tend to decline while mean flows in August and September increase. Other significant adjustments included changes in annual hydrograph conditions, primarily in the number of hydrograph reversals that has generally increased for almost all sites following impoundment. The number of high pulses has increased following impoundment but the average length declines. The mean rate of hydrograph rise and fall has declined significantly. These results indicate that the major pulse of dam construction during the previous century has modified hydrologic regimes on a nationwide scale, for large and small rivers. © 2005 Elsevier B.V. All rights reserved. 2006 Uncertainty in predicting riverbed erosion caused by urban stormwater discharge Daebel H. and Gujer W. Water Science and Technology 2005 52/5 (77-85) Ecologically based criteria require an integrated modeling approach. Due to the complexity of the system, the stochastic nature of loads, and the model abstractions, many uncertainties are involved. In this study, a simple integrated model is applied, which Swiss engineers employ to assess the impact of urban stormwater discharges on riverbed stability. In the course of a case study, an uncertainty analysis is carried out focusing on parameter uncertainties. The underlying context of the uncertainties is evaluated, and a variance-based sensitivity analysis is presented estimating the local uncertainty contribution of each parameter. The results reveal that the largest contributions stem from the model components describing the natural system. An experimental design is proposed that manages to reduce the output uncertainty significantly. Finally, we discuss the benefits of following the proposed procedure. © IWA Publishing 2005. 2007 Intergranular flow velocity through salmonid redds: Sensitivity to fines infiltration from low intensity sediment transport events Zimmermann A.E. and Lapointe M. River Research and Applications 2005 21/8 (865-881) This paper presents results from a novel technique allowing continuous monitoring through multiple storm events of interstitial flow in salmonid redds. Previous studies have shown that longterm increases in fine sediment inputs into rivers can silt up spawning beds, reduce intergravel flow and threaten egg survival. 384 HYDROLOGY Not enough is known, however, about the temporal and spatial scales of the physical processes affecting spawning habitat. The short-term sensitivity of intergravel flow through salmon nests to low-intensity sediment transport events has not been documented. Furthermore, it is unclear if the egg pocket flow vital to incubation is principally controlled by the hydraulic conductivity of the redd patch or by that, generally lower, of the ambient riffle substrate. The purpose of this study was to determine if individual runoff events could affect intergravel flow in salmon nests and to investigate the sensitivity of interstitial flow to the fines content and conductivity of the redd patch. During the summer and autumn of 2001, a new intergravel velocity sensor based on the hot wire principle made it possible to continuously monitor, over five months, interstitial velocities in artificial redds in four tributaries of the Cascapedia River, Quebec. Fifteen low and moderate intensity runoff events (up to 50% bankfull) were monitored. Data were obtained for each storm on suspended sediment transport as well as sand infiltration rates in sediment collectors emplaced in redd zones. It was found that redd interstitial velocities were reduced whenever a runoff event deposited more than 7 kg/m2 of sands in infiltration traps. In addition, redd interstitial velocities were reduced four out of the five times that the event-integrated suspended sediment dose exceeded 7 mg1-1 day (dose is defined as the area under the concentration time curve). In the study conditions, where ambient riffle sediment has relatively moderate permeability and localized groundwater upwelling is negligible, our data suggest that significant intergravel flow (0.1-0.6mm/s) can be triggered through 2m long redd patches, in response to the redd-scale water surface gradient and the relatively higher conductivity of the redd patch, after spawner activity. Copyright © 2005 John Wiley & Sons, Ltd. 2008 Streambed sediment composition and deposition in a forested stream: Spatial and temporal analysis St- Hilaire A., Caissie D., Cunjak R.A. and Bourgeois G. River Research and Applications 2005 21/8 (883-898) Assessment of fish habitat quality often includes the measurement of substrate composition and fine sediment deposition in streams. The natural spatial (localized, inter-reach) and temporal (event-specific, seasonal, annual) variability of both sediment deposition and streambed composition were investigated in Catamaran Brook (New Brunswick, Canada). A grab-type sampler (i.e. scoop) and Whitlock-Vibert boxes were used to investigate grain size distribution of streambed material and deposition of fine sediments over time. Results showed that the scoop sampler was a good method to quantify intra-site and inter-site grain-size distribution, especially as it relates to the streambed composition and changes thereof. In Catamaran Brook, scoop samples showed that gravel constituted the highest percentage of the total dry weight with a median of 38.8%, for seven sites monitored in three different study reaches. The median percentage of fines (i.e. material <2 mm) was found to be 10.8% of total weight. Intrasite variation in substrate grain size distribution was also assessed using the scoop sampler. Significant differences in the distribution of fine sediments within a study reach as well as among habitat types (riffles, runs, etc.) were found, which reiterates the importance of taking multiple samples. To observe changes in fine sediment, a subsample of the scoop sampler limited to grain sizes <32 mm was used to reduce some of the variability in weight percentages due to large substrate material, e.g. cobbles. The percentage of fines within this subsample varied between 15.2% and 20.0% (overall median of
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