HYDROCHEMISTRY OF THE ZEYA RESERVOIR IN HIGH-WATER YEARS

Abstract

The results of studying the chemical composition of the waters of the Zeya reservoir in high-water years (2013, 2021) are presented. It is shown that a signifi cant infl ow of water into the reservoir during these years caused in its waters a uniform distribution of concentrations of dissolved substances in the water area and depth in the summer- autumn period and extremely uneven in winter. The maximum values of mineralization, concentrations of calcium, magnesium, bicarbonate and sulfate ions, ammonium nitrogen, organic substances and dissolved iron were established in winter in the estuarine areas of the Argi and Zey regions as a result of the infl uence of cryogenic processes and fl ooding of the marshes of the Upper Zey plain. In the dam and canyon parts of the reservoir in winter, there were no large diff erences in mineralization values (28,4–41,9 mg/dm3), low content of ammonium nitrogen (< 0,03 mg N/dm3), increased values of water color (62–87°), concentrations of dissolved iron (0,35–0,74 mg/dm3) and organic matter (10,0–13,3 mg O/dm3). An assumption is made about the receipt of large amounts of dissolved substances in the Amur River in winter due to increased water consumption of the Zeyskaya HPP