Summary

ubidus tenuis, whose propotion is increasing in the forest areas terated with lime.
3.2. Earthworm fauna changes due to forest liming
Although the boreal pine forest eutrophication and trasnformation processes
may be observed close to every bigger city of Northern and Central Europe, as well
as in territories where dynamic optional acctivities are being applied, therefore the
literature lacks of data on what effect do such changes have on the soil animals, and,
what is the possible soil animal impact on these processes. In Western Europe the
pine forest transformation problems are being considered by another point of view,
that is, in relation with forest liming, which is being implemented in order to improve
tree growth in poor soils and to reduce soil acidity caused by pollution (Robinson et
al., 1992a).
Several essential factors for earthworms are being changed by lime applicationsoil
acidity, content of calcium changes appear in microorganism consistence, which
are the potential nutritients, and others. After lime application, the earthworm density
as a rule increases. In Finland, after forest treatment with lime, esentially increased
population of Lumbricus rubellus, while population of Dendrobaena octaedra did
not change. It was observed that presence of Aporrectodea caliginosa reduces
population of Dendrobaena octaedra (Persson, 1988; Robinson et al., 1992).
Usually the most important reason of live animal population density increase is
the improvement of the nutritient base, or changes in the mutual competition of live
organisms (Persson, 1988). After lime application, reduces proportion of C:N in the
organic horizon of the soil (Zelles et al., 1990). Proportion C:N is one of the most
important earthworm population limiting factors (Lee, 1985). Conifers, moss and
lichen contain considerably less N and mineral substances than decidious trees and
vascular plants (Аристовская, 1980). Presence of vascular plant remains in O
horizon’s considerably favours increase of earthwomn population (McLean et al.,
1996). If soil acidity reduces, nitrogen mineralization happens faster, and increases
contrentation of the available nitrogen forms in the soil (Robinson et al., 1992a).
Earthworms facilitate different processes in the soil, including also formation of
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