The article presents the data of ecological and chemical monitoring of small rivers of the Angara region, held in october 2014–2017. The chemical composition and ecological state of the rivers flowing through the territory of the Bohan district of the Irkutsk region are considered: Baley, Ira, Kachig, Olonka, Taras and Ida. Assessment of ecological and chemical state of small rivers of Bohansky district was carried out according to the following criteria: pH, degree of water salinity, concentration of basic ions, content of some microelements, such as Zn, Cu, Al, Ba, Pb, Ni, Sr. Concentrations of nutrients and petroleum products were also determined. It was found that the water in the rivers corresponds to the standards of water bodies of household and cultural-drinking appointments. However, in some rivers the exceedances of MPC for fishery water bodies were determined by the content of Zn, Cu, Co, Al, Sr, nutrients and oil products. This is mainly due to natural factors. Anthropogenic impact on the studied rivers is insignificant.

Yanchuk Maria Sergeevna, Junior Researcher, V. B. Sochava Institute of Geography SB RAS, 1, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation, tel.: (3952)42-70-89, e-mail: m_s_yanchuk@mail.ru

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