Abstract
The article describes the ecological state of the Ural River at the present stage. Hydrochemical regime of the reservoir is an important indicator to regulating the number of water resources. As the Ural River is the transboundary reservoir, it is prone to contamination from various areas in the upper and middle reaches. Monitoring of the ecological state of the Ural River showed the presence of anthropogenic pollution. The hydrochemical regime of the reservoir is subject to changes in seasonal variations in water composition. In spring, with flood waters, the main pollution enters the river, however in other seasons, the quality of water leaves much to be desired. In autumn, in comparison with the spring, both alkalinity and salinity increased. The reservoir is prone to contamination with nitrites in almost all seasons of the year from 0.05 to 0.20 mg/dm3 (December, 2016). In the lower reaches of the Ural River, the content of readily oxidizable organic compounds ranges from 3.2 mg/dm3 (winter) to 7.36 mg/dm3 (autumn). The content of boron exceeds the maximum permissible concentration 1-3 times. Environmental monitoring conducted in different periods of the year showed a constant source of pollution flow into the reservoir, which was increased in the flood period. Concentrations of nitrite, boron and petroleum products in the Ural River exceed their permitted values at the point in the end of Uralsk city. The results of the research confirm that the source of the contamination of Ural River is its confluent Ilek River originating from Aktobe Oblast.