Kazan State University of Architecture and Engineering
Abstract
Surface sediments of thermokarst lakes along the temperature gradient were
sampled in northwestern Siberia. The lakes were distributed through three environmental
zones: typical tundra, southern tundra and forest-tundra, which were all situated within
the continuous permafrost zone. Our investigation showed that the cladoceran communities
in the lakes of the region are represented by diverse, abundant communities as reflected
by the taxonomic richness and high diversity indices. The differences in the cladoceran
assemblages were related to the limnological and geographical position, vegetation
type, climate and water chemistry. The constrained redundancy analysis (RDA) indicated
that the TJuly, water depth and both sulphate (SOf ~) and silicium (Si4*) concentrations
statistically significant (p < 0.05) explained the variance in the cladoceran assemblage