ASSESSMENT OF ENVIRONMENTAL RISK OF DETERIORATION OF SURFACE WATERS OF THE MIDDLE DNIEPER SUB-BASIN WITHIN THE POLTAVA REGION

Abstract

The work is devoted to the assessment of the ecological risk of deterioration of the surface waters of the middle Dnieper sub-basin within the Poltava region. The relevance of the study is that the assessment of quality and analysis of the current state of natural waters is a very important step in the organization of safe for life and health of the population drinking water supply. The aim of the work is to assess the environmental risk of deterioration of surface waters within the Poltava region. The object of study is the surface waters of the middle Dnieper sub-basin. The subject of the study is the environmental risk of deterioration of surface waters. The originality and methodology of the study is that the work uses a set of methodological approaches. In particular, the quality of surface water objects was assessed according to the Methodology of ecological assessment of surface water quality by relevant categories, the results of which became the basis for assessing the environmental risk of deterioration of surface waters of the middle Dnieper sub-basin with the help of Methodology for assessing the environmental risk of deterioration of water objects according to hydrochemical observations and Methodology for assessing environmental risk. Conclusions. According to the results of the assessment of the quality of surface water objects within the Poltava region in 2019, it was established that the maximum contribution to pollution is made by the category of tropho-saprobiological indicators, the highest by priority: nitrite and nitrate ions, phosphates, which worsen the state of water to the 7th category with the qualification – "very bad" state and "very polluted" water in terms of purity. The worst environmental conditions and the highest degree of water pollution are observed at the monitoring point № 8 in the river Sukhy Omelnyk (below the discharge from the commercial utility company of the air town of Globyne). According to the results of the calculation of environmental risk, it is established that a high risk of deterioration of the ecological status of water resources is observed in the content of chloride ion; nitrite, nitrate and phosphate ions; petroleum products, copper, surfactants and total iron. The maximum level of risk of deterioration of surface water within the middle Dnieper sub-basin is observed at observation point № 11 (Orzhytsia River below the water treatment facilities from the Orzhytsya Dairy Plant). This point relates to those that allow you to record the deterioration of water, due to discharges of waste water into the river. The practical value of the study is that its results should be used to make proper management environmental decisions to reduce anthropogenic inprint on water resources by preventing the inflow of insufficiently treated waste waters into the surface water objects and to implement water protection measures in the middle Dnieper basin within Poltava region.