Abstract—

The intense pollution due to increased anthropogenic load on the water catchment areas is a problem of small rivers. Changes in the hydrochemical regime of small rivers have an impact on large rivers as well, since the former feed the latter with transfer of pollutants from the land. Agricultural and communal water pollution of small rivers can be the cause of degradation of the river system. Therefore, systematic monitoring and comprehensive evaluation of the water quality of small rivers against the background of climatic changes and low water is an urgent problem for the water management of Ukraine. This study is aimed at assessing the ecological state of the Umanka River (the left tributary of the Yatran’ River) in a certain period of time, which makes it possible to follow changes in water quality under the influence of anthropogenic factors and natural and climatic conditions of low water. Based on the results of analytical measurements of water samples of the Umanka River bed, the following block indices of water quality are calculated: index I₁ of contamination by the components of the saline composition (the sum of the Cl^– and \({\text{SO}}_{4}^{{2 - }}\) ions); ecological and sanitary index I₂ (\({\text{NH}}_{4}^{ + }\), \({\text{NO}}_{2}^{ - }\), \({\text{NO}}_{3}^{ - }\), PO, and pH); and index I₃ of specific indicators of toxic action (Fe_tot, Cd, Pb, Cu, and Zn). According to hydrochemical parameters, the Umanka River water—which is a potential source of drinking water supply—is contaminated with nitrogen compounds \({\text{NH}}_{4}^{ + }\), \({\text{NO}}_{2}^{ - }\), and \({\text{NO}}_{3}^{ - }\), and with Cd and Pb, and has a high level of permanganate oxidation exceeding the fourth class level of surface water quality. A comprehensive ecological assessment of the river water with values ranging from 3.51 to 4.36 along the stream is carried out, and the water quality is characterized as transitioning from “good” and “fairly pure” to “satisfactory” and “slightly polluted” with a tendency to approach “mediocre” and “moderately polluted”, while the Umanka River water in 2004 was classified as “good” and “fairly pure”.

中文翻译：

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乌曼卡河流域地表水水质环境评价

摘要——

由于人为负荷增加对集水区造成的严重污染是小河流的问题。小河流水化学状况的变化也会对大河流产生影响，因为前者将陆地上的污染物输送给后者。小河流的农业和公共水污染可能是河流系统退化的原因。因此，在气候变化和低水位背景下对小河流水质进行系统监测和综合评价是乌克兰水资源管理亟待解决的问题。本研究旨在评估乌曼卡河（Yatran’河左支流）在一定时期内的生态状况，这使得可以跟踪人为因素以及低水位自然和气候条件影响下的水质变化。根据乌曼卡河床水样的分析测量结果，计算出以下水质块指数： 指数I ₁盐水成分的污染（Cl ^-和\({\text{SO}}_{4}^{{2 - }}\)离子的总和）；生态卫生指数I ₂ ( \({\text{NH}}_{4}^{ + }\) , \({\text{NO}}_{2}^{ - }\) , \({ \text{NO}}_{3}^{ - }\)、PO 和 pH)；和毒性作用具体指标的指数I _{3 (Fe tot}、Cd、Pb、Cu和Zn)。根据水化学参数，作为潜在饮用水供应源的乌曼卡河水受到氮化合物污染\({\text{NH}}_{4}^{ + }\) , \({\text {否}}_{2}^{ - }\)、\({\text{NO}}_{3}^{ - }\)、Cd、Pb，高锰酸盐氧化程度高，超过地表水水质四类标准。对沿流3.51～4.36的河水进行综合生态评价，水质由“良好”、“尚纯净”过渡到“良好”、“轻度污染”，水质状况良好。 2004 年乌曼卡河水的水质等级为“良好”和“相当纯净”。