Zooplankton community structure of Volzhsko-Kamsky National Nature Reserve

Abstract

Long-term studies had been held on the lakes of the Volga-Kama State Natural Reserve (Russia). The aim of our research was to study the biodiversity of planktonic rotifers and crustaceans, zooplankton community structure characteristics and also water quality assessment with bioindication methods. 137 species of zooplankton were identified in our research. In all lakes rotifers were presented by highest number of species. The lowest number ofspecies was found for copepods. In general, the species composition of zooplankton is typical for eutrophic lakes of Middle Volga region. The species most commonly found in lakes are indicators of eutrophic waters. We also analyzed and compared the structure of zooplankton communities and taxonomic composition in different types of nature reserve lakes. It was shown that changing the relationship between taxonomic groups of zooplankton and increase of rotifers in the community is also a sign of eutrophication. According to the abundance rotifers dominated in most lakes. Drastic changes in quantitative indicators of zooplankton during the growing season, due to an increase in the abundance of one of the species were typical of eutrophic lakes of the reserve. Studies have shown that in meso-eutrophic and eutrophic lakes the indicators that reflect the structure of the zooplankton community are the most informative for the assessment of the water quality. Lakes Raifskoe and Ilinskoe were the least polluted, and characterized by the structure of communities of mesotrophic type. The rest of the lakes are more prone to eutrophication processes and community structure of zooplankton corresponds to eutrophic lakes type.