ECOLOGICAL GROUPS OF FRESH-WATER GASTROPO DS IN THE CENTRAL PART OF EUROPEAN RUSSIA - THE INFLUENCE OF THE TYPE OF WATER BODY AND SUBSTRATE

Basing on 370 samples from the central part of European Russia, the fr eshwater gastropods are classified with the respect to their occurence in different biotopes. Ecological groups of species are distinguished . The influence of the water body type and substrate on the species co mposition of these groups is considered. The significant correlation b etween the species composition and the water body type is shown. The i nfluence of the substrate type is much lesser. The correlation between the mobility of gastropods and the substrate preferences of the speci es is discussed as well as the influence of the mosaicism of substrate s.