Analysis of Correlations between Water Quality Indicators in the Dnipro River Basin Due to Climate Changes and Anthropogenic Load

The analysis of correlations between the quality indicators of water resources is carried out for the Dnipro River representing a strategic water resource of Ukraine as an example. The studies show an increase in the concentrations of contaminants, such as ammonium ions, nitrates, nitrites, and chlorides due to excessive water discharge and climate changes. In particular, significant distinctions in the dynamics of water quality indicators on the left and right banks of the Kremenchuk Reservoir are observed to evidence a nonuniform character of load on the water resources. The objective of this study is to determine the effect of climate changes and anthropogenic load on the quality indicators of surface water in the Kremenchuk Reservoir. Mathematic modeling by means of regression analysis, statistical data processing, and analysis of trends in water quality indicators for the period from 2016 to 2024 are performed. It has been revealed that most of the studied indicators do not correspond to the normal distribution law due to a complex effect of climatic and anthropogenic factors. Correlation analysis results evidence that temperature cycle has an essential effect on the organic water parameters and the seasonal character of their change. At the same time, chlorides and dissolved oxygen remain stable and independent of temperature fluctuations. The conclusions of this papers emphasize importance of adaption to European standards, introduction of advanced water treatment methods, and reformation in the water supply and sewage infractructure. A key problem in attaining the sustainable development and European integration goals of Ukraine is to preserve the qualitative state of water resources.