FIELD TABLES for Humus Forms Classification

HUMUSICA Fundamental vocabulary and tables For observing the soil in the field we generally open a cubic hole in the ground. Facing the hole on our knees, we look to a face of the cube (50 cm x 50 cm, or more), which is a real object (humus form profile) composed of layers of different colour and structure, each of them being also a real object (humus forms horizon). Comparing these real objects in different sites, we defined the corresponding concepts of humus form and diagnostic horizon. Similar humus forms were also grouped in larger units labelled humus form interaction systems, or humus systems. These terms being very common all over the book, we would like to fix their definition just now: 1-­‐ REAL OBJECTS (FIG. 1) Humus form horizon = organic or organo-­‐mineral topsoil layer; the topsoil is made of few horizons overlaying like the pages of a book and labelled all together humus form profile; each horizon can be assigned to an abstract category labelled “diagnostic horizon”; Humus form profile = face of a parallelepiped hole in the soil, comprising humus form organic and organo-­‐mineral horizons; this object made of few humus form horizons can be assigned to an abstract category labelled “humus form”. Abstraction
Diagnostic
horizons
Reality
Humus form
horizons
OL
OF et OH
A
B
SOIL PROFILE
Organic horizons
HUMUS FORM
PROFILE
Organo-mineral horizon
(Mineral horizons)
C
Figure 1. Real humus form profile and horizons and abstract diagnostic horizons. Alpine beech forest with Amphi humus system. 2-­‐ CONCEPTS Diagnostic horizon = reference for organic or organ-­‐mineral horizons, defined by characters and qualities that stay within prescribed limits; Codes of diagnostic horizons, Terrestrial: OLn, OLv, OFzo, OFnoz, OH, maA, meA, miA, Anoz; Histic: Hf, Hm, Hszo; Hsnoz, Hsl, Aa; Semi-­‐
terrestrial: OLg, OFg, OHf, Ag (or: maAg, meAg, miAg, Anozg), AEg. Humus form = (HF recommended) = reference for a group of humus form profiles having the same series of diagnostic horizons. Terrestrial HF : Pachytangel, Eutangel, Leptotangel, Pachyamphi, Eumesoamphi, Eumarcoamphi, Leptoamphi, Oligomull, Eumull, Mesomull, Dysmull, Hemimoder, Eumoder, Dysmoder, Hemimor, Humimor et Eumor; Histic HF: Euanmoor, Limianmoor, Saprianmoor, Limisaprimoor, Eusaprimoor, Oligosaprimoor, Humiamphimoor, Euamphimoor, Fibriamphimoor, Saprimesimoor, Humimesimoor, Eumesimoor, Fibrimesimoor, Saprifibrimoor and Humifibrimoor, Eufibrimoor. At larger scale, similar humus forms profiles will be found in a single relatively homogeneous ecosystem (a forest, or a meadow, or…); then, on a conceptual statement, these humus forms are grouped in a single “Humus form interaction system”. This level of organisation is very important for the purposes of this book and allows to see by naked eyes the features of a specific “soil functioning”. Humus system (abbreviating of "Humus form interaction system", HS recommended) = reference for a group of humus form profiles showing the same main characters and having nearly the same ecological determinants (biological, mixt or abiotic) which range in announced values; Terrestrial humus systems: Tangel, Amphi, Mull, Moder, Mor; Histic: Anmoor, Saprimoor, Amphimoor, Mesimoor, Fibrimoor. Interaction system: outward dimension element of the analysis of the natural organisation, according to the operator theory. Here down the figure 1 and its legend, as appear in the article of Gerard et al. (2014) that clarifies the role of acting operators in universal structures. In the outward dimension, the Humus system can be considered as an Ecosystem placed in the first (5-­‐50) cm of soil (Fig. 2). 3-­‐ STRUCTURE OF THE CLASSIFICATION A humus system has to be understood as a biological system that operates the biodegradation of the dead organic matter produced in a given inhabited place of the planet. There are Terrestrial humus systems and forms (submersed from few months to few days per year), Histic humus systems and forms (submersed the largest part of the year), Semiterrestrial intergrades which are defined using the prefixes Hydro (if presence of Ag or AEg horizons, intergrades from Terrestrial to Histo) or Epihisto (if combiner presence of Ag or AEg and H or Aa histic horizons, intergrades from Histo to Terrestrial) and Para humus systems and forms, atypical systems and forms dynamically more or less relied to the formers. An overview of the proposed classification of humus systems is illustrated on figure 3. The main systems are in the centre, 5 Terrestrial disposed in “V” along two ranges starting from a neutral point (Mull), on siliceous rock on the left and on calcareous on the right, and 5 Histo, listed from left to right from more to less submerged. Two Prefix, Hydro and Epihisto (and some diagnostic horizons listed on the left of the tables 1 and 2), allow to classify all the situations occurring along a gradient between Terrestrial and Histo systems. All around are placed the Para systems, corresponding to “young” phases of central systems (arrows indicate that Para are constantly attracted by the centre). Even if dynamically attracted, they can stay “young” for centuries or millenaries, blocked by hard climatic conditions or constant erosion. Strongly influenced by man, the Para Agro and Techno systems has been set in black/grey and does not occupy a fixed place, rather in a temperate and relatively drained situation, more propitious for crops and grazing, or anthropic sites. Figure 1: Three dimensions for the analysis of organisation according to the operator theory. The
upward dimension depicts a transition from an operator of a lower type to an operator of the
adjacent higher type. The inward dimension focuses on various kinds of organisation in the interior of
an operator. The outward dimension depicts various groupings of operators according to certain
grouping rules. Thick black arrow: transitions between operator types. Thin black arrow: organisation
in the interior or an operator. Thin dashed arrows: contribution of operators to low level abstract
grouping. Circles are used to indicate increasingly inclusive (abstract) groupings of concepts. For
practical reasons only a limited part of the upward dimension is shown.
The second perspective of the inward dimension describes the organisation one can find within any
Figure 2. Figure with its legend xtracted from
from article of Galways
erard must
et astart
l. (2014) that clarifies individual
operator.
When
definingeconcepts
thethe ground
up, we
with defining
the an
role of acting operators in universal structures. n the oThe
utward dimension, the operator,
before
we can analyse
the organisation
in its Iinterior.
internal
organisation
canHumus system can always
be considered a
s a
n E
cosystem, w
ith c
ommunities o
f p
lants a
nd a
nimals c
o-­‐acting be analysed using different perspectives, such as displacement, information construction andin a information,
DICE
approach,
that was explained
in Jagers op Akkerhuis (2008).
shared physic the
and chemical environment. Diagnostic horizons reveal the natural structure of an undisturbed soil. In tilled or artificial soils The third perspective of the outward dimension describes all complexity which is the result of
the interactions
described between
vertical operators.
series of Ithorizons often cannot be detected. However, the organisms living is crucial here that the outward dimension describes all objects
in tthat
he sare
oil rnot
epeatedly r
e-­‐build t
he o
riginal tructure and little etc.
by Any
little the soil rdoes
ecovers operators, e.g. footballs, cars, bee scolonies,
ecosystems,
such
object
not its functional andwich appearance. A coperator,
hapter oand
f this dedicated to a,rtificial have the srequired
topology
for being an
is m
a anual ed a ii s te
a tio s ste
because ithumus forms, which have parted in agro-­‐systems nd each
techno-­‐systems, he first roup related consists
ofbaeen group
of operators
that interact a
with
other (in othertways
thangthat
lead
to the to formationpofrocesses, an operator).
defining
an interaction
from the ground
agronomic the When
second to industrial or wsystem
aste treatments. up, it must always
be explained from the interactions between operators. Organisation in interaction systems can also
be analysed according to different (and overlapping) perspectives, as for example the DICE approach
indicates (Jagers op Akkerhuis 2008).
If we start with using these three dimensions for analysing organisation and hierarchy in our
analyses, this leads to the observation that many existing analyses seem to amalgamate the
principles that, according to the operator theory, belong to three separate dimensions of systems
analysis. We use the following example for illustrating the utility of using three dimensions.
We imagine a ranking that starts with an atom, and continues via a molecule and organelle, to a cell,
the organism and the population.
18
HUMUS&SYSTEMS&
Cyanobacteria/&
lichens/algae/fungi&!
PARA!=!Strongly!
influenced!by:!
Crusto!
TERRO&
TANGEL&
MOR&
Bryo!
Techno&
Ser
ies &
Agro&
Man&
MULL&
SemiMterrestrial&
HYDRO&
EPIHISTO&
Water&table&
FIBRI&
MOOR&
Ligno!
AMPHI&
MOOR&
Man&
CaC
&
SiO 2
AMPHI&
MODER&
O&
3 Se
rie
s
&
Mosses!
SAPRI&
MOOR&
ANMOOR&
MESI&
MOOR&
Rhizo!
HISTO&
Wood&decomposers!
Figure 3. Relationships between Humus systems and classification. Roots/rhizomes&!
Tabe 1. Diagnostic horizons of TERRESTRIAL HUMUS SYSTEM and FORMS and Hydro intergrades (Hydromorphic Terrestrial humus forms). Above: acid series; underlying: Calcareous series. Legend HYDRO = prefix to utilize if presence of “g horizons” (horizons periodically hydromorphic, horizons water-­‐
saturated less than few months per year), examples: OL + maA = Mesomull; OL + Ag or OLg + Ag = Stagnic Mesomull; (typical) = tacit, without “g horizons ”= in typical terrestrial condition (horizons water-­‐saturated less than few days per year) ; possible = horizon present or absent or thickness < 2 mm; “g horizons” could be present with or without typical (non-­‐hydromorphic) horizons; not sufficient for using the Stagnic prefix possible and mandatory = horizon present or absent or thickness < 2 mm, but mandatory present for using the Hydro prefix; example: Hydromull; Hydrooligomull; Hydromoder…. OH > 2A = thickness of OH horizon > 2 times thickness of A horizon; A ≥ OH/2 = thickness of A horizon ≥ half the thickness of OH horizon; disc pock = horizon discontinuous or in pockets; ≥ 3 cm = thickness of indicated horizon ≥ 3 centimeters; or = the indicated horizon could be present instead of another indicated horizon; and/or = the indicated horizon could be present with or instead of another indicated horizon. DIAGNOSTIC;HORIZONS;
and;Transition;OAA
HYDRO
(typical)
OLg,;OFg,;OHg;
possible;but;
not;sufficient;
for;using;the;
prefix;Hydro
OLn
EU
AMPHI
LEPTO
PACHY
Possible%not%discriminant
OLv
EUMESO
MULL
EUMACRO
LEPTO
OLIGO
EU
MODER
MESO
DYS
disc%pock
Possible%,%not%discriminant
MOR
EU
DYS
Possible%,%not%discriminant
OF
disc%pock
Anoz
HUMI
EU
Possible%,%not%discriminant
disc%pock
≥%3%cm
<%3%cm
≥%5
<%5%
≥%1%cm
<%1%cm
disc%pock
<%5
<%3
≤%1%cm
>%1%cm
≥%5
msA
miA%and/or%meA
or
disc%pock
disc%pock
<%3
sgA,%msA
miA
meA
HEMI
disc%pock
OH%>%2A;%
OH%>%2A;%
OH%>%2A;%
(OH+OF)>30%cm (OH+OF):%15L30 (OH+OF)<15%cm
A%absent%=%E%or%sgA,%or%msA
or
or%only%meA%A%≥%OH/2
or
or
A%≥%OH/2
maA
MANDATORY:
In%Tangel:%pHwater%of%msA%≥%4.5
In%Amphi,%one%of%the%following:%living%eartworms%or%freshly%deposed%earthworm%feaces%in%A;%diffuse%transition%A/O;%%pHwater%of%A%≥%5
In%Mull,%one%of%the%following:%presence%of%living%earthworm%or%their%casts%in%A;%transition%O/A%<3%mm;%pHwater%>%5
In%Moder,%one%of%the%following:%transition%O/A%≥%5mm;%pHwaterof%A%<%5
In%Mor,%three%of%the%following:%presence%of%OFnoz;%transition%O/ALE%<%3mm;%pHwater%of%E%or%A%<4.5;%A%absent%or%presence%of%msA%or%sgA%or%E
HEMI
OFnoz
OH
Transition;OAA;(mm)
Anozg,;Ag;
possible;and;
mandatory;
for;Hydro
TANGEL
PACHY
Tabe 2. Diagnostic horizons of SEMITERRESTRIAL HUMUS SYSTEM and FORMS and Epihisto intergrades (partially drained Semiterrestrial humus forms) Legend EPIHISTO = prefix to use if presence of horizons periodically hydromorphic (horizons with “g” index: Ag, AEg). These “g horizons” are not present in a fixed position of the profile but generate at different levels in it, sometimes even parting in two a main organic or organo-­‐mineral horizon. The presence of OLg, OFg and OHg horizons is not sufficient for using the prefix Epihistic, examples: Hs, Aa = Hs, Aa, Ag = Limimull; Hs, Aa, Ag dominant (thickness Ag > Aa) = Epihistic Limimull; (typical) = tacit, suffix not reported in the name = without periodically hydromorphic g horizons but with water-­‐saturated at least 6 months per year horizons = typical semiterrestrial humus forms; possible = horizon present or absent or thickness < 2 millimetres; not sufficient for using the Epihisto prefix; examples: Epihistoanmoor; Epihistollimianmoor; Epihistomoder. possible and mandatory = horizon present or absent or thickness < 2 mm, but mandatory present for using the Epihisto prefix; variable = horizon variable in thickness; dominant = horizon thicker than each other single horizon of the series. NB: The relative thickness of the horizons is graphically indicated in the table (grey area) because it influences the result of the classification, ex: Fibrimesimoor = Hm>Hf>Hsnoz; Eumesimoor = Hm>Hsnoz>Hf. ANMOOR
DIAGNOSTIC?HORIZONS
EPIHISTO
(typical)
EU
LIMI
SAPRIMOOR
SAPRI
LIMI
EU
AMPHIMOOR
OLIGO
HUMI
EU
MESIMOOR
FIBRI
SAPRI
HUMI
EU
FIBRIMOOR
FIBRI
SAPRI
HUMI
EU
Hf
Hm
OLg,?OFg,?
OHg?
possible?
but?not?
sufficient??
for?using?
Epihisto?
prefix
Hs
Hsnoz
possible
Hsl
Aa
Ag,?Anozg,?
AEg?
possible?
and?
mandatory?
for?using?
Epihisto?
prefix
Ag
dominant
Anozg
Aeg
Table 3. Para humus Systems (or Prefix), still under discussion Legend The name of Para Humus System can be used alone when no diagnostic characters allow to assign a Para form to a Terrestrial or Semiterrestrial Humus System or Form. It is also possible to combine two (or even three ?) names, placing them in a decreasing importance, setting the dominant system at the head. Example: Rhizo-­‐Bryo, when a Rhizo system shows patches of mosses here and there. Crusto are often a mosaic of visible community of algae, lichens and mosses: it is relatively easy to see that this community does make sense rather as a whole than as separate single elements. Humus
System
Description
Diagnostic characters
Dynamic considerations
Crusto
Biological complex mosaic of
cyanobacteria, green algae, lichens,
mosses, microfungi, and other bacteria
Cyanobacterial and microfungal filaments are
weaved throughout the top few millimeters of
soil, gluing loose particles and forming a matrix
that stabilizes and protects soil surfaces from
erosion
Bryo
Mosses totally covering the soil and
forming a stratified carpet or cushion
Moss material more than 75% of thickness or
with living (green) parts overgrowing a volume of combined organic diagnostic horizons
layer of dead stems and leaves
Rhizo
Organic and/or mineral-organic
Root material more than 50% of thickness or
diagnostic horizons almost entirely
volume of combined organic diagnostic horizons
made of root material (living and dead)
Ligno
Organic diagnostic horizons almost
entirely made of wood decayed by
fungi and tunnelled by invertebrates
Pioneer ecosystems of arid and polar
deserts and rocky outcrops, harsh
climate condition, permanent or
periodic lack of water, nutrients or
soil, phases of incipient pedogenesis
Pioneer ecosystems succeeding to
biological crusts in cold, arid or wet
environments (peat formation); also in
mosaic on boulders or under forest
trees on eroded soil
Heathland and grassland ecosystems
built by grass, fern, ericaceous and
other suffrutescent or scrub vegetation
Specific ecosystems exploiting the
energy released during wood
decomposition. The process of
decomposition takes place on the
ground or on stems and branches still
on standind dead trees. Very common
in old-growth forests, particularly in
unmanaged temperate and tropical
forests.
Agro
Techno
Humus form under prominent man
influence: Agrimull or Compost or
Mulch or other artificial organic or
mineral-organic mixtures
Humus form under prominent, directly
or indirectly man influence: sewage
sludge, tossic waste, landfill waste,
colonized masonry wastes, more or less
structured Edifisols
Decaying wood more than 75% of thickness or
volume of combined organic diagnostic horizons.
Presence of animals and animal droppings linked
to wood decay
Tillage profile or managed dump of organic
remains
Agricultural fields, market gardens,
kitchen gardens
Artefacts or waste materials more than 50% of
thickness or volume of combined organic and
organo-mineral diagnostic horizons.
Landfills, urban soils, heaps of waste,
industrial waste,…