Water and sediment microbial communities in shallow coastal ecosystems of Lake Baikal during summer 2021-2022

Abstract

The taxonomical structure of the microbial community of shallow coastal areas is closely related to environmental conditions, and also changes rapidly in response to changes determined by water level fluctuations. The taxonomic structure of microbial communities in the shallow coastal areas of the Lake Baikal was studied during the period of high water level in summer months 2021-2022. At the phylum level, Proteobacteria, Actinobacteriota, Bacteroidota, Firmicutes, Cyanobacteria, Verrucomicrobiota and Deinococcota were dominant, accounting for 98.55 to 99.46% of the total microbial diversity in water microbial community. A significant similarity was revealed in the taxonomic composition of microbial communities in the shallow coastal areas of the Lake Baikal during certain summer months of 2021-2022. Similar water microbial communities formed in June 2021/22; in July 2022 in the Enkhaluk and Sukhaya sample sites, as well as at the Goryachinsk and Sukhaya sample sites in August 2022. Sediment microbial communities were dominated by Gammaproteobacteria, Bacteroidota, Alphaproteobacteria, Actinobacteriota and Verrucomicrobiota.