Hydrochemical And Bacterial Properties Of Water Bodies Of The East European Plain During Low Water Period

This paper is devoted to the study of the chemical and biological properties of river waters and the relationship between them. We examined the hydrochemical and bacterial properties of surface water in 3 waterbodies: the Mezha River, a pond in Zapovedny village (Central Forest Nature Reserve, Tver Oblast) and the lower reaches of the Don River (Rostov Oblast). The biodiversity of bacteria was determined based on their growth on dissolved organic matter (DOM). Among bacterioplankton capable of growing on DOM as the only source of carbon, the predominant species in the Don River were Pseudomonas and Deinococcus, in the Mezha River – Pseudomonas and Janthinobacterium, in the pond – Arcicella. In terms of sanitary and microbiological indicators, none of the waterbodies complied with the Sanitary Rules and Regulations 1.2.3685- 21 for surface waters. The content of most of the studied elements and heterotrophic bacteria in stagnant waterbodies was lower than in flowing streams. The concentration and activity of heterotrophic bacteria in the studied waters correlated positively with the content of biophilic elements in them and negatively with the absence of a current. We showed that there is a strong correlation between bacterial and chemical indicators due to common factors: eutrophication, features of the physical and geographical conditions of the territory, and the presence of a current or animal waste products.