Joint International Conference on Long-term Experiments ...

tend not to give enough information about the biological state or activity and diversity
of soils.
Collembola (springtails), as a representative group of soil fauna, has relatively low
biomass, but it is extremely important in influencing the structure of some soils. For
example, “alpine pitch rendzinas” on limestone have a black humus layer that is formed
almost entirely of Collembola feces. However, most soils have millions of collembolan
fecal pellets on each square meter (Hopkin, 2002). Springtails play important role in
decomposition and soil respiration through feeding on fungal hyphae. These effects are
beneficial in the aspect of soil structure, moisture regime, soil organic content, cation
exchange capacity, nutrient availability, that determine healthy soil functions (Cole,
2005). It is believed that soil degradation processes lead changes in the activity and
composition of the soil fauna (Larsen, 2004). Soil scientists have been considering a
highly diverse community of soil organisms to indicate good soil quality (Brady and
Weil, 1999).
The objective of this presented study was to find quantitative relationship between
the physical and the biological (and biochemical) degradation processes along an
erosion catena. The degradation of soil fauna was examined by the number and the
species composition of collembolans. It was expected that not only the abiotic factors
(soil-moisture, aeration, compaction) but also biotic factors, such as microbiological
activity are important ecological factors for soil animal communities. The appropriate
measurements and scaling of these effects can serve as a basis for soil biological
degradation assessments.
MATERIALS AND METHODS
1. Study area: The study was conducted on Szent István University Experimental Farm
in Józsefmajor, north central Hungary. Four soil profiles were examined in detail on a
topographic catena, representing different levels of erosion (no, low, high erosion and
accumulation profiles). The first two profiles are Chernozem soils, the third one, which
is the most eroded profile, is a Calcisol and the fourth one at the bottom of the valley is
a Cumulic Chernozem.
2. Laboratory analyses: The following general laboratory analyses were carried out on
the four soil profiles: soil organic matter (SOM %) determined by Walkley–Black
method (Walkley, 1947); cation exchange capacity (CEC) by Mehlich method;
pH(H2O) and pH(KCl) determined electrometrically (Buzás, 1988); texture; CaCO3
content by Scheibler method; and bulk density (BD) determination (Buzás, 1988). The
simplified moisture retention was also determined on the soil samples to find out the
level of physical degradation.
Besides the general laboratory analyses the following biochemical properties were
determined: water soluble carbon (WSC) and carbohydrates (WSChy) (Garcia, 1997),
enzimatic characterization (Veisz, 2004), urease, and ß-glucosidase activity (Garcia,
1997).
3. Experimental design for biological aspects: Collembola was sampled by regular
sampling, along a transect in eleven points with 20 m distances from each other. The
first four points belonged to the non eroded region, whereas the 5-8th points were low
eroded and the 9th, 10th points represented the most eroded parts of the transect. Soil
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