Peculiarities of macrozoobenthos structure formation in riffles of the Karelian coast of the White sea

Abstract

Species composition, abundance and biomass of macrozoobenthos were investigated in the riffles of the Karelian coast of the White Sea. The longitudinal dynamics of benthic communities’ structure is weak due to the stony-bottomed riffles almost throughout the rivers. Local factors can cause significant changes in the structure of macrozoobenthos. Thus, the communities with high level of filter-feeders biomass (net-weaving caddis fly larvae, the midge larvae, bivalves) are formed in the river sites downstream from the drainage lakes. In the areas affected by salty sea waters (parts of the river mouth), macrozoobenthos structure is significantly depleted. Local landscape features should be considered when describing the longitudinal changes in macrozoobenthos structure of rivers.

Keywords

• benthos
• macrozoobenthos
• bottom communities
• structure
• rivers
• the white sea
• karelian coast