Natural background and transformation of water quality in the Moskva River

Abstract

Abstract Longitudinal transformation of several hydrochemical parameters in the Moskva River was reviewed based on the data of extensive monitoring studies conducted in 2019-2020. Changes of the chemical composition and their seasonal variation were quantified in relation to the only remaining natural part of the river above the Mozhaysk Reservoir. We found that the overall variability of element concentrations in the part of the Moskva River not affected by anthropogenic pressure is much lower than the magnitude of changes caused by urban influence. The effect of residential and industrial development in the watershed is comparable to, or sometimes much lower than the impact of polluted wastewater discharged by Lyubertsy and Kurianovo treatment plants. Point-source pollution therefore plays the key part in the transformation of the natural water quality in the Moskva River.