USING AN INTEGRATED APPROACH TO ASSESS THE CURRENT ENVIRONMENTAL STATE OF THE BESHTEREK RIVER

Abstract

Introduction. The problem of restoring and preserving the environmental state of watercourses with an increase in anthropogenic load has recently become more urgent, but the use of only one method or approach does not allow us to judge the current state of a river, so there is a need to combine various methods aimed at obtaining integrated information. The purpose of this study was to analyze the environmental state of the water bodies in the Beshterek River Basin (Republic of Crimea). Methods. The studies were carried out during 2018–2019 and included: visual observations of the watercourse state, water-protection zone, channel ponds; water flow measurement; sampling for the study of water chemistry; calculation of the water pollution index (WPI) and the integrated indicator of ecological condition (IIEC); study of water toxicity by means of bio-assay techniques using wheat and cress seeds; development of environmental measures. Results. The studies have found that the main pollutants in river water are sulfates, phosphates as well as heavy metals: Cd, Pb, Cu, Zn. The concentration of sulfates increased from 0.15–0.22 MAC (upper river) to 1.5–2.4 MAC (mouth of the river), which indicates the ingress of domestic wastewater into the watercourse. The content of phosphates in the middle reaches exceeded the standards by 1.9–11.1 times. The heavy metal content exceeding the MAC was recorded at all river stations: zinc (station No. 1 — 2.1 MAC), cadmium (station No. 3 — 1.24 MAC), lead (station No. 4 — 1.23 MAC) and copper (station No. 4 — 1.5–10 MAC). The water quality in terms of the WPI was II and III (“clean” and “moderately polluted”) in the river and II, III and IV (“polluted”) in the channel ponds. The bio-assay testing showed no toxic effect on the test cultures. Conclusion. Among the priorities, the following can be distinguished: the need to establish a permanent monitoring network for the observation of the qualitative and quantitative characteristics of the river flow, and develop a program for sewage handling in villages located in the river valley.