The species composition of zooplankton in waterbodies and watercourses of the great lakes depression

The species composition of zooplankton in lakes, reservoirs, and watercourses of the Great Lakes Depression (Mongolia) is examined. Its changes depending on the type of water objects and water mineralization are shown. Under changes in the climate and the economic situation in Mongolia, the species diversity in fresh waterbodies is seen to increase, which is also due to species that are indicators of eutrophication. The minimum changes in the species composition take place in highly mineralized lakes where zooplankton is characterized by the lowest species diversity. The formation of the zooplankton faunistic composition corresponds to changes that were observed earlier in reservoirs of the Volga cascade. The species composition of zooplankton in watercourses varies significantly and depends on the character of the source of a river and its length.