Golden algae (Chrysophyta) in plankton of the Volga River reservoirs: Taxonomic structure,dynamics of diversity,and abundance

Long-term (1953–2004) published and original data on the taxonomic composition and ecological and geographical characteristics of planktonic crysophytes have been systematized and the degree of similarity of the crysophyte flora in nine reservoirs of the Volga River basin has been assessed. Patterns of changes in the specific species richness and biomass of golden algae along the longitudinal profile of the Volga River reservoirs are identified. The relationship between species richness and some abiotic and biolimnological parameters has been analyzed. The decline in diversity and biomass of golden algae in direction from the Upper to the Lower Volga in accordance with the geographical zoning is revealed. The long-term dynamics (1954–2011) of the species richness, abundance, and biomass of golden algae has been analyzed. A positive correlation between the diversity and biomass of golden algae and the amount of precipitation and water temperature is demonstrated.