The Hydrochemistry and Hydrobiology of Technogenic Reservoirs at Mining Territories of the Southeastern Transbaikal Region

摘要

Reservoirs of anthropogenic genesis are a special component of the technogenic landscape. Their environmental conditions differ from those of natural water bodies. Such differences include a limited catchment area and a low thickness of bottom sediments, as well as high contents of metals, metalloids, and salts. The objects of our research are various lake formations that formed during the development of mineral deposits in the Eastern Transbaikal region. This article describes the chemical composition of the waters and the species diversity and the structure of hydrobiont communities that are different in their formation and purpose of technogenic reservoirs of mining areas. Algae and zooplankton of technogenic water bodies in a region with an arid climate have been studied for the first time. The studied waters have a variety of morphometric and physicochemical characteristics with a wide range of pH values (2.99-8.80), total mineralization (85.9-9065 mg/L), and content of ore and associated elements. According to the chemical composition, the waters are sulphate and bicarbonate-sulphate, with different ratios of magnesium and calcium. The species diversity of the algae and zooplankton of the studied water bodies is low (75 taxa of plankton algae, 8 taxa of macroalgae, and 63 species and subspecies of plankton invertebrates). This is associated with extreme environmental conditions, where species richness is influenced by physicochemical conditions of the habitat. The determining factors for the development of Cryptophyta representatives are micro- and macrocomponent composition and general mineralization, for other groups of phytoplankton (Cyanobacteria, Bacillariophyta, Chrysophyta, Charophyta, Chlorophyta, Euglenophyta, and Dynophyta) it was the content of bicarbonates. Quantitative indicators of zooplankton are positively related to the concentration of ammonium nitrogen (for Crustacea) and negatively to pH (Rotifera).