Аңдатпа
In this research, the results of a hydro-chemical study of Lake Kopa in Kazakhstan are described, in thecontext of the regional geography and aggravating ecological problems of the lake. Besides analyzingthe concentrations of all major ions, heavy-metal ions and other pollutants, their vertical andhorizontal distribution were also assessed. Moreover, water pollution indices (WPI) were calculatedfor individual ions, classes of pollutants, and total pollution, revealing serious overload of human-induced pollution within the lake’s ecosystem. Concentrations of major ions and WPI were monitoredover 2009-2013 period, revealing a distinct seasonal pattern and a multi-year periodicity in respect tothe measured parameters. In addition, studying ion exchange between lake water and bottomsediment showed complex non-equilibrium processes besides leaching out Ca2+ and its exchange forNa+.