Features of the long-term dynamics of development hydro/chemical parameters of the water of the Shershnevsk Reservoir

The article presents an analysis of the long-term dynamics of the hydrochemical conditions of the water of the Shershnevsky reservoir for 1972-2020 during the spring flood and summer low water. The features of the development of water quality indicators over time are determined: pH, mineralization, turbidity, color, suspended solids, the content of dissolved oxygen and organic substances by permanganate oxidability and BPK5, as well as changes in the concentrations of ammonium, nitrite, nitrate nitrogen and phosphates. In the water of the Shershnevsky reservoir for the period 1972-2020, trends of a significant decrease in mineralization, turbidity and permanganate oxidability were noted in both phases of the hydrological mode. In the summer low water period, a significant increase in chromaticity, oxygen content in water and orthophosphates was detected.. The revealed features of changes in the hydrochemical regime indicate an increase in the processes of anthropogenic eutrophication of the Shershnevsky reservoir – the only drinking source of the Chelyabinsk agglomeration and make it possible to predict the state of the aquatic ecosystem. The information obtained can be implemented in the process of making management decisions on environmental protection measures for the Shershnevsky reservoir.