Summary

changes. That allows to identify soil eutrophication already in its initial stages. The
most important quantitative indicators reflecting these processes are increase of the
total earthworm population, and formation of a stable Lumbricus rubellus population.
Further stages of eutrophication processes feature changes of the earthworm
communitie dominance structure- Dendrobaena octaedra, as the dominant species in
natural forests, is replaced by Lumbricus rubellus. Greatly eutrophicated biotypes are
characterized with formation of 3 to 4 species communities and diversification of the
earthworm ecological groups. Very essential is formation of the endogeic
populations, especially Aporrectodea caliginosa, what may occur only in a particular
stage of the organic matter decomposition (Стриганова, 1980). Aporrectodea
caliginosa is one of the most important soil animal representatives, which as a key
species may significantly influence and quicken both processes in the soil and
processes of the ecosystem. Formation of a stable population of Aporrectodea
caliginosa may indicate on irreversible changes in the soil. However, pine forest
eutrophication final stages may be easily identified by fitocenotic changes.
Earthworms, as a bioindicator of these processes, have greater significance in the
indication of the initial stages.
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