Ecologically Tolerable Impact Levels of Abiotic Factors in Water Bodies in Russia and Neighboring Countries: Dependence on the Geographic and Climatic Conditions

Largest river basins in Russia, Lithuania, Ukraine, and Uzbekistan are compared with respect to the admissible levels of the environmental physicochemical factors, the violation of which entails ecological disturbance of hydrobiont communities. The determination analysis of data is used to study the dependence of the degree of adaptation of limnetic ecosystems to external impacts on the sampling site (water column or ground), the latitude, climate, distance from sea, and the density of population in the region under study. Geographical and climatic classifications of regions are proposed based on the variability in the limits of environmental tolerance to abiotic impacts.