Assessment of the impact of the formation of water resources and the quality of surface waters of the Lena River basin

Abstract

Ongoing active development of natural resources, changing climatic conditions (including permafrost melting) In Eastern Siberia, it is necessary to control changes in the ecological state of the environment, one of which is surface water. The Roshydromet system has established and successfully operates a network of regime observations of the state and pollution of surface waters of the Russian Federation, ensuring the unity of measurement of the content of major pollutants in water according to uniform methods certified in accordance with the requirements of regulatory documents of the Russian Federation and international standards. In this paper, the formation of the quality of the surface waters of the Lena River basin under conditions of non–stationary climatic processes on the one hand and the anthropogenic component on the other is considered. Based on the analysis of statistically processed long–term data (2011-2021) obtained by the state monitoring network of Roshydromet, an assessment of the water quality of the Lena River and its major tributaries - the Vitim, Olekma, Aldan, Vilyu rivers is given. The spatio-temporal distribution of characteristic pollutants in the water of the rivers of the basin has been studied: organic substances (according to BPK5 and COD), phenols, petroleum products, iron, copper and zinc compounds. It was found that in the conditions of the Arctic climate, the seasonal distribution of organic substances in surface waters was insignificant. The presence of heavy metal compounds in the water of the Lena River basin water bodies is mainly due to anthropogenic sources of pollution. In the long-term plan, the water of the rivers of the Lena River basin was assessed as the 3rd satisfactory quality class.