State and dynamics of zooplankton in Kazan Bay of the Kuibyshev Reservoir in 2018

Abstract

During the growing season of 2018, the composition and dynamics of zooplankton in the Kazan Bay of the Kuibyshev Reservoir were studied. In total, 69 zooplankton taxa were identified, the species richness of zooplankton was 9 ± 1 taxa per station, abundance, 221.9 ± 32.1 thous. ind./m3, biomass, 1.6 ± 0.5 g/m3, average daily production, 0.124 ± 0.034 g/m3 per day. Two peaks were observed in the dynamics of quantitative characteristics of zooplankton (in June and in August), which was typical for mesotrophic lakes of temperate latitudes in accordance with Sommer’s PEG model. Two-factor ANOSIM analysis, performed on the basis of the similarity of stations in terms of the contribution of species to total production, evidenced on the influence of the month of sampling (R = 0.472; p = 0.001) and distance from the lower boundary of bay mouth (R = 0.279; p = 0.001) on the structure of zooplankton communities. The factor of station location relative to the banks and riverbed did not have a significant effect on the composition of zooplankton (R = −0.028; p = 0.94). Pollution in the Kazan Bay in 2018 corresponded to the longterm average level in the β-mesosaprobic zone, which characterized the waters as moderately polluted.

Keywords

• kazanka river
• spatial analysis
• zooplankton succession