The species composition and the taxonomic structure of phytoplankton in the lakes of Omsk region

To assess the biodiversity of plankton algae from different types of Omsk lakes, phytoplankton studies were carried out in September 2020. The material was quantitative and qualitative phytoplankton samples taken from 38 lakes in Omsk region. The collection and processing of phytoplankton samples were carried out by the methods generally accepted in hydrobiology. The phytoplankton from Irtysh lakes is characterized by high species richness and complex structures. 382 species and intraspecific taxa (IWT) have been identified, including the nomenclature type of species from 8 divisions. 25 new algae from 6 divisions were identified in the study. The greatest species richness is characteristic of green algae (Chlorophyta); euglena algae (Euglenophyta) and cyanoprokaryotes (Cyanoprokaryota) also have a high diversity, which corresponds to the importance of these divisions in the taxonomic structure of phytoplankton in Omsk Irtysh region. The greatest diversity of phytoplankton was observed in old lakes; highly eutrophic shallow lakes in the south have a specific taxonomic structure. Low species richness of phytoplankton is characteristic of highly mineralized lakes.