Marie Jokerud Utrecht March 10
21/04/2011 BEGIN – Biodiversity of European Grassland – the impact of Atmospheric Nitrogen Deposition MARI JOKERUD Ecological & Environmental Change Research Group Department of Biology University of Bergen Stevens CJ, Dise NB, Moundford JO, Gowing DJ (2004). Impact of nitrogen deposition on the specie richness of grasslands. Science 303:1876–1879 Supervisor: VIGDIS VANDVIK Is to determine whether N-deposition is impacting species richness and species composition on ombrotrophic mires in Western Norway Critical Load Some vulnerable habitats Europe – exceeded Ombrotrophic mires Norway – exceeded to some degree Poor grasslands Costal heatlands Habitat Mire Vegetation type mg N/m2/ yr Effects Ombrotrophic mire (D1 Raised and blanket bogs) 500-1000 Increase in vascular plants, change in moss flora, nitrogen saturation in Sphagnum, N-accumulation in peat and peat water D2.2 Poor fens 1000-2000 Increase in Juncaceae, Cyperaceae and vascular plants, negative effect on Sphagnum D4.1 Rich fens 1500-3500 Increase in tall grasses, decrease in diversity Adjusted after Achermann & Bobbink (2003) by Bruteig & Aarrestad (2004) RESAMPLE STUDY Resample two historical datasets on ombrotrophic mire community composition in low-deposition (1965-68) and high-deposition (1978) areas. Hypothesis: Greater change in species richness and composition, high-deposition region Increase in minerotrophic species in the high-deposition region. GRADIENT STUDY Sample 25 mires along a N-deposition gradient Hypothesis: Change in species richness and composition Higher N-deposition → More minerotrophic species 1 21/04/2011 © Jutta Kapfer © Jutta Kapfer © Jutta Kapfer © Jutta Kapfer Hitra 1965-1968 150 plot 0.5 x 0.5 m plots Hult-Sernander du Rietz © Jutta Kapfer © Jutta Kapfer Austre Moland 1978 150 plot 0.5 x 0.5 m plots Hult-Sernander du Rietz Analyses Compare dataset Species richness Species composition Ellenberg values Norwegian Institute for Air Research 2 21/04/2011 6 Norwegian mire reserve survey 1970 – 1980s Western Norway: ca 500 localities 7 Carex livida Carex demissa Viola palustris Carex dioica Sphagnum teres Pedicularis palustris Sphagnum warnstorfii Rhynchospora fusca Warnstorfia exannulata Aneura pinguis 8 9 10 Parnassia palustris Bartsia alpina Carex hostiana Tofieldia pusilla Carex pulicaris Carex lepidocarpa Campylum stellatum Eriophorum latofolium Juncus triglumis Scorpidium scorpioides Calliergon giganteum Schoenus ferrugineus Tomentypnum nitens Calliergonella cuspidata Fissidens adianthoides Fremstad 1997 Average mm pr year NR Locality 1 Botnemyr 2 Storemyr 3 Storslåtta 4 Bervamyr 5 N for Lundsmyr 6 Dyrlimyra 7 Ugjellsvannet 8 Hellemyra 9 Myrer V for Brattåsen 10 Vinddalen 11 Måmyra 12 Øyastøl 13 Fossastølen 14 Myr SV for Ringås 15 Skitdikane 16 Eikevolltjønnmyra 17 Dalemannsvege 18 Myr ved Kleppstølsvatn 19 Myr ved Dalesætrane 20 Myr ved Sætervatnet 21 Djupmyra 22 Myr ved Gjerstad 23 Myr V for Sørli 24 Myr V og N for Storelv 25 Havmyrene Municipality Froland Åmli Evje & Hornnes Sirdal Bjørnestølheia Kvinesdal Lista Lista Marnardal Forsand Hjelmeland Hjelmeland Etne Lindås Voss Flora Gaular Naustdal Bremanger Bremanger Vestnes Surnadal Averøy Tustna Hitra Average C during growing season Nitrogen zone Number of localities County Øst-Agder Øst-Agder Øst-Agder Vest-Agder Vest-Agder Vest-Agder Vest-Agder Vest-Agder Vest-Agder Rogaland Rogaland Rogaland Hordaland Hordaland Hordaland Sogn & Fjordane Sogn & Fjordane Sogn & Fjordane Sogn & Fjordane Sogn & Fjordane Møre & Romsdal Møre & Romsdal Møre & Romsdal Møre & Romsdal Sør-Trøndelag 6 6 6 4 3 Norwegian Institute for Air Research 3 21/04/2011 25 Localities (5 in each nitrogen zone) 10 plot per locality 0.5 x 0.5 m plots Estimate % cover Total 250 plots Analyses Patterns along the N-deposition gradient Species richness, species composition, nitrogen indicators Compare to previous description and classification (1975) – change in presence of species, increase in minerotrophic species Critical load Norwegian Institute for Air Research Norwegian Institute for Air Research [email protected] 4
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