Invasions of Diatom Algae in the Kama and Votkinsk Reservoirs

Abstract

On the basis of the analysis of the published data and materials of our studies on phytoplankton, the distribution of eight alien species of diatom algae in the Kama and Votkinsk reservoirs is considered. It is noted that only Actinocyclus normanii (Greg.) Hust. reaches considerable development. The diameter of the valve of A. normanii varies from 16.5 to 48.5 μm, and the size of the valves of this species decreases from the north to the south. The dynamics of the abundance and biomass of this species is considered during a long-term period (2004–2017); its distribution is studied over the water area of the reservoirs. A change in the size of A. normanii is observed depending on the mineralization and water temperature. It is shown that there is no correlation between the quantitative development of the species in the reservoirs of the Middle Kama and the changes in temperature and water content of a year, content of biogenic elements, water mineralization, proportion of cyanoprokaryota (cyanobacteria), and the total number of phytoplankton.