Установление уровня деградации воды участков водных объектов, используемых для отведения дренажно-сбросных вод с орошаемых земель

Abstract

Purpose: to determine the level of water degradation in the areas of water bodies used to divert drainage and waste water from irrigated lands of the Central irrigated district of Rostov region. Materials and methods. The object of study was the drainage and waste water inlets – sections of the Sal, the Salt, the Podpol’naya, the Western Manych rivers and the Beshenny yerik. The assessment of water quality in the background section line of the water body and in the section of drainage water inlet from irrigated lands was conducted according to the specific combinatorial water pollution index (SCWPI) and the complex indicator of anthropogenic load. Results. According to the SCWPI, water in the Salt river and the Besheny yerik is assessed as polluted, 3rd class, category “a”, in the background section line of the Sal river – as the 3rd class, category “b”, very polluted, in the outlet section line of drainage and waste water – as the 4th class, category “a”, dirty. The intraseasonal dynamics of the anthropogenic load index for the studied watercourses showed that in the Salt, the Podpol’naya, the Western Manych rivers throughout the entire irrigation period, the self-cleaning ability of water bodies is higher than the rate of degradation processes. The depletion processes prevail over the recovery process in the Sal river and the Besheny yerik in the study area. Conclusions. It has been determined that the complex indicator of anthropogenic load exceeds the conditionally normative indicator in the estimated section of the Sal river by more than 3 times, this indicates the damage to the aquatic environment from the drainage and waste water discharge. The rest of the studied river ecosystems are in their natural state, do not experience or experience weakly anthropogenic impact from water pollution. In certain periods of the irrigation season, the river ecosystem of the Besheny yerik experiences a short-term moderate anthropogenic load.