Prospects of application of Elodea canadensis Michx in the complex assessment of the state of small rivers in the zone of influence of technogenic objects of the Kalush mining and industrial district (Kalush district, Ivano-Frankivsk region, Ukraine)

The breach of natural balance arose as a result of anthropogenic transformation of rocks during the operation of Kalush-Holynsk deposit of potassium salts, due to irrational location of tailings, dumps, accumulating tanks and long functioning of objects of chemical industry (landfill of toxic waste of Oriana-Halev Limited company in particular). The most pronounced are the changes in the river ecosystems of the region, due to the violation of hydrogeological conditions and the introduction of a wide range of pollutants into the environment. The rivers of the region belong to the Carpathian part of the Dniester river and take part in the formation of its runoff, so their anthropogenic transformation can lead to the breach of the entire Dniester river ecosystem. Systematic control over changes in river water quality indicators is an urgent task of ecological and applied research and a prerequisite for effective management of the ecological condition of the entire Dniester river basin.

The research was conducted in 2020–2021. The ecotoxicological condition of the Sivka, Sapohiv, Limnytsia rivers was assessed on the sections of their flow through the Kalush mining and industrial area and on the relevant background areas.

He presented experiment was preceded by chemical-analytical studies to determine the cationic-anionic composition, background hydrological indices and organochlorine compounds. The results allowed us to state that the studied rivers can be referred to three quality classes: the Sivka river - to the 7th class (extremely polluted waters); the Sapohiv river – to the 3rd class (moderately polluted waters); the Limnytsia river – to the 2nd class (clean water). At the same time, chlorides are a priority factor of the pollution of the Sivka river, and traces of hexachlorobenzene are present in the water of the the Sapohiv river.