Hydrochemical features of the Tuzlov River as an indicator of the consequences of industrial and agricultural activities in Eastern Donbass (Rostov-on-Don Region, Russia)

Abstract

The spatial and temporal variability of solute transport, chemical composition and water quality in the Tuzlov River basin for the period 2003–2019 has been considered. The purpose of this study was to consider the Tuzlov basin as an indicator of the consequences of economic activity in the territory of Eastern Donbass. The results obtained on the transport of dissolved substances in the upper part of the basin showed an increase in the transport of major ions, on the contrary, a decreasing trend in the transport of copper, zinc and phosphorus phosphate compounds. Further, the variability of water chemistry in the middle section of the basin, as well as at the observation sites above and below Novocherkassk was considered. In the middle reaches, the increase in the content of major ions continued, and a sharp increase in the concentration of phosphorus phosphate was recorded. The tendency to reduction of copper and zinc compounds remained the same. Below Novocherkassk — at the closing site of hydrochemical observations — the content of phosphorus phosphates, copper and zinc compounds increased to the greatest extent. Water quality during the period under consideration remained at the level of class 4 (“dirty”), its spatial and temporal variability was insignificant. Based on the results obtained, conclusions were made about the leading role of the consequences of coal mining in the increase in the content of major ions (primarily due to sulfate ions) and total iron compounds in water. At the same time, agricultural activities in the catchment lead to a decrease in the content of copper, zinc and phosphorus phosphate compounds in water. However, at the most urbanized Tuzlov River site in the city of Novocherkassk, the content of these components in water increased significantly. The results of the study may be useful in planning conservation measures in the studied area.