Summary

changes dominance structure, Dendrobaena octaedra is replaced by Lumbricus
rubellus. Populations of endogeic Aporrectodea caliginosa form in greatly
eutrophicated biocommunities.
7. Formation of humus horizon in the eutrophicated soils create additional
living-space for earthworms, both with appropriate feeding conditions and possibility
to migrate into deeper layers in case of unfavorable meteorological conditions.
8. Earthwrom activities in the eutrophicated forest soils become an essential
inner factor of the biocenosis, and initiate further soil transformation process.
Earthworms improve physical soil properties, activate breakdown of the organic
matter and their spread into the soil profile, thus promoting formation of thicker
humus horizon. Close to the populated areas establishment of new earthworm
populations occur faster than in isolated forest areas, therefore, in such areas quicken
the forest eutrophication processes.
9. Earthworms are considered as great indicatiors of the oligotrophic pine
forest eutrophication processes. The most important bioindicative indicators in the
initial stages of the eutrophication processes are the total earthworm population
density increase, 3 to 4 species earthworm communities, formation of a stable
Lumbricus rubellus population, and expansion of the ecological group spectrum.
10. Changes in earthworm communities are being detected before visual
changes in the forest phytocenosis. That allows to identify soil eutrophication in its
initial stages.
40