HYDROCHEMICAL REGIME AND ECOLOGICAL STATE OF SURFACE WATERS IN THE SYNIUKHA RIVER BASIN

Preserving and restoring the ecological status of rivers in the southern regions of Ukraine is long- standing and pressing issue. These territories have a significant permanent water shortage. The problem of water supply has been exacerbated not only by military operations, but also by climatic factors, including the record- breaking hot summer of 2024. The Syniukha River is one of the largest tributaries of the lower part of the Southern Bug, whose water is actively used in various areas of economic activity. The results of the analysis of the dynamics of the hydrochemical regime and the assessment of the quality of surface waters of the Syniukha River for the period from 1993 to 2023 show that the degree of pollution of the river's waters varies according to different indicators. The water quality in the river corresponded to Class II and was described as good. Over the many years, the highest pollution was observed for nitrogen and phosphorus compounds, and the deterioration of dissolved oxygen. The state of the Syniukha River in its upper reaches is not environmentally stable due to the high level of anthropogenic pressure on the river, which exceeds the capacity of the river's aquatic ecosystem to regenerate itself. Deterioration of the ecological state of the Syniukha River requires constant monitoring by environmental institutions and the implementation of water protection measures.