Water ability to self-cleaning as quantitative evaluation of their ecological condition

The article discusses the main indicators that should underlie the assessment of the ecological well-being of a natural water body. These include the chemical composition of water, the ratio of indicators of photosynthetic activity and destructive activity, analysis of phytoplankton species composition, biochemical self-purification index, dehydrogenase activity of sludge, and it is necessary to analyze them in the complex. This system analysis (for the definition of ecological well-being) is subject to three aquatic ecosystems: the middle river, the large river and the reservoir).