Ecological and floristic characteristics of phytoplankton in the contact zone on the cascade of the Volga reservoirs

The paper summarizes the results of long-term observations of the state of phytoplankton in the contact zone on the cascade of the Volga reservoirs in the period 2014-2018. The research was conducted by the network of hydrobiological laboratories of Roshydromet. The studied water bodies represented a cascade of alternating water bodies of various types lying in different geographical zones and characterized by various hydrological factors and the intensity of anthropogenic load. A comparative analysis of the qualitative and quantitative characteristics of the phytoplankton of the contact zone along the Volga riverbed and its reservoirs was carried out, and the main structural characteristics of the phytoplankton community were identified. There were 358 species and variations of phytoplankton found. Among them there were 139 species of diatoms and 133 - of green algae traditionally prevailing in terms of the number of species. Cyanobacteria (36 species) and euglenic algae (24 species) possessed significant species diversity. The remaining departments were represented by single species, so dinophytes were represented by 5 species, chrysophyseae algae - by 13 species, cryptophytes - by 7 species, and there was one species of yellow-green algae discovered.