Екологічний стан озера у с. Оріховиця

Abstract

The study deals with the ecological state of the lake in the Orikhovitsa village of Uzhhorod district of Transcarpathian region, which is used for unorganized recreation and fishing by the residents of the nearby villages. To analyze the water quality according to standard methods, a number of hydrochemical parameters were set, in particular pH, chloride-, sulfate-, nitrate-, nitrite anions, polyphosphates, ammonium ions; suspended solids, Ferum total, dissolved Oxygen, BSC5, HCC and permanganate oxidation. The obtained results were compared with the normalized values determined for the reservoirs, used of recreation, everyday life and fishery purposes. The analysis of the results indicates that, that according to the defined hydrochemical and sanitary-hygienic indicators of water quality (except total iron, suspended solids and microbial contamination) no exceedance of the normalized values for both water use purposes was observed. The content of the Ferum total exceeded the normalized values for reservoirs of recreation purpose by 1.7 times. In the same time the exceedance in 2.4-10.0 times in case of water reservoirs for industrial fishing during all seasons represents a significant risk for human health and for aquatic organisms as well. The content of suspended matter in all selected water samples from the lake exceeded the normalized values for reservoirs of recreational purposes, which is ≤ 0.75 mg/dm3, and ranged from 5.0 mg/dm3 to 6.8 mg/dm3, which is 6.7-9.1 times more, than the set value. Due to the ability of suspended solids to absorb contaminants and microflora on their surface as well as for aesthetic reasons, this reservoir cannot be considered suitable for swimming. However, according to the requirements for fish farms, all water samples taken from the lake met the quality standards according to the relevant indicator. The results of microbiological analysis of the state of the reservoir in the summer time show that the reservoir does not meet the sanitary and hygienic standards for the bacterial content of Escherichia coli, Staphylococcus aureus and Streptococcus. The content of pathogenic strains of staphylococci and molds exceeded the normalized values. Warning signs notifing of this fact should be installed. Keywords: ecological state; hydrochemical parameters; microbiological analysis; health; hydrobionts; Transcarpathian region.