THE ECOLOGICAL-TOXICOLOGICAL CONDITION OF THE WATERS IN THE SOTK AND MASRIK RIVERS AND IN THE ARABLE LANDS OF THE NEIGHBORING AGROCENOSIS UNDER THE INFLUENCE OF THE SOTK MINE EXPLOITATION

Abstract

Upon the investigations it has been disclosed that along with the increase of the dimensions in the mining industry, as well as with the increase of rock dump amounts, the organoleptic and chemical indices of the waters in the Sotk and Masrik rivers have also grown up. The amount of suspended particles per liter of water has increased for the last 10 years by 210%...317.0% or by 32.1 mg/l in the waters of the Sotk River and by 13.2 mg/l in the Masrik River. Similar changes have also been observed in the indices of nitrates, sulphates and hydrogen values, which are mainly related to the chemical composition of the mountainous rocks, where the alkaline chemicals mainly predominate (Ca, K, Na, Mg, etc.) and also to the intensive agricultural activities conducted in the given area, particularly in the riverine areas, as well as to the development of the livestock sector. Meanwhile, it has been found out upon investigations that both in the previous 10 years and similarly in 2019, the content of heavy metals and other chemical elements in the Sotk and Masrik Rivers and in the lands of their adjacent agroecosystems, the total intensity of their geochemical stream considerably varied and fluctuated related to the exploitation of the Sotk mine and to the changes of the ore mining dimensions. To reduce the mobility of heavy metals and to improve the ecological-toxicological conditions of the mentioned rivers and ploughlands irrigated with those waters, it is necessary to continuously add the lime amount CaO in the acidic drainage of the mining site so that the water environment reaction would hold up at least within the range of 9 (pH 9). Besides, individual heavy metals (such as tungsten, molybdenum, vanadium, etc.) are more active in the alkaline medium, hence, for their refining it is necessary to install filters as well.