Hydrochemical regime of some lakes of Kokshetau upland

The hydrochemical indicators of lakes Imantau, Shalkar (North-Kazakhstan region), Zerenda, Kopa (Akmola region) located on the Kokshetau upland for 2022-2023 are shown in the article. Lake Zerenda, Imantau, Shalkar - the largest water reservoir of STNP "Kokshetau". Lake Kopa is located in the center of Kokshetau, in the most urbanized area of the region. Between the studied years, there is a change in some indicators, as well as indicators exceeding the MPC. In connection with the increase in anthropogenic load on water bodies, it is important to update research annually, and hydrobiological research with hydrochemical parameters is also conducted. An increase in the amount of ammonium ions is noted in lakes Zerendа, Kopa, Imantau and Shalkar, which is a sign of pollution by organic substances. In addition, sharp changes in the chemical composition of water are observed in Lake Shalkar, where a sharp increase in mineralization is observed, which requires further studies of the state of the reservoir. The chemical composition of Lake Zerendа is relatively stable, but there is a high concentration of sodium and potassium exceeding the MPC. The levels of magnesium and calcium are also higher than normal, which indicates a higher level of minerals in the water.