Influence of runoff regulation on hydrochemical indicators of water in small rivers on the example of the Teplaya river in the Saratov region

Small rivers are extremely sensitive to any anthropogenic activity, including runoff regulation, and serve as a kind of indicator of the ecological state of natural complexes. In general, large rivers are well studied, and small water bodies are practically not studied, although they are of great economic importance. For Teplaya river of the Saratov region was given an ecological and geographical characteristic, sources of anthropogenic load on the reservoir were identified, an analysis was made of the degree of knowledge and background indicators of the rivers of this basin. On the example of Teplaya river effect of runoff regulation of a small river by a dam on a number of physical and chemical parameters of pond water quality is considered. It has been established that the water temperature in the Teplaya river in the autumn period before the runoff regulation was a constant value, and after the dam it increased to the last sampling point downstream. The hydrogen index varied within 7.5-8.4, the total mineralization of water consistently increased in the studied section of the river (0.66-1.08 g/dm3). It is shown that the content of ammonium ions and nitrites was much higher than the sanitary and hygienic standards, which indicates the uniform nature of fresh organic water pollution in this section of the river. An increase in the concentration of chlorides in the last of the cascade of ponds was established - almost 1.5 times compared to the higher sampling points, which, however, did not exceed the standard values.