Assessment of water quality in the area of Kizhi Museum-Reserve (Lake Onego) by bacterioplankton indicators in summer of 2023

Abstract

In summer 2023 the size and morphological structure of bacterioplankton, quantitative indicators of ecological-trophic groups of bacteria and total coliform bacteria were determined in the area of Kizhi Island a water body of Lake Onego. The morphological structure of the cells was dominated by bacilliform bacteria, indicating the presence of easily mineralizable organic matter (OM). The total bacteria abundance, heterotrophic and saprophytic groups of bacterioplankton confirmed the increased content of easily mineralizable OM in the area of Kizhi skerries. The development of phenol-oxidizing and hydrocarbon-oxidizing bacteria revealed water pollution with phenolic compounds and oil products. High indicators of total coliform bacteria indicated the presence of opportunistic microorganisms, the number of which almost everywhere exceeded the norms for waterbodies of recreational use. The most polluted area of Kizhi skerries is the western part, characterized by active shipping and low water exchange.