Bioindication assessment of the ecological state of Sevastopol coastal waters
Active exploitation of coastal areas in combination with technogenic pollution inevitably leads to the depletion of biological resources and the deterioration of their condition. Sevastopol aquatic area is one of these areas, used as a collector of various pollutants. In this regard control of water pollution and the state of biota in Sevastopol bays are the main tasks of regional environmental monitoring using bioindication methods. Microbial indication methods make it possible to detect and control the appearance of pollutants in water much earlier than the irreversible toxic effects of aquatic organisms occur. Mussels are often used as bioindicators of seawater pollution, due to the significant accumulation of pollutants in their body at a relatively low concentration of pollutants in the environment. Ecological state of Sevastopol coastal waters was assessed. The studies were carried out in three Sevastopol bays with different levels of pollution in the summer 2019 - Laspi, Kazachya, Streletskaya. The estimation was based on the results of microbiological monitoring of bottom sediments (total number of heterotrophic bacteria and the number of hydrocarbon-oxidizing bacteria) and parameters of the prooxidant-antioxidant system (level of oxidized proteins and lipid peroxidation, superoxide dismutase and catalase activities) in hepatopancreas of mussel Mytilus galloprovincialis . Maximum abundance of heterotrophic and hydrocarbon-oxidizing microorganisms was found in soils of Streletskaya Bay, minimal abundance - in bottom sediments of Laspi. A significant increase of the prooxidant-antioxidant system parameters in hepatopancreas of mussels from Streletskaya Bay compared with Kazachya Bay and Laspi Bay was noted. The results obtained indicate a high level of pollution and less favorable living conditions for aquatic organisms in Streletskaya Bay. The studied indicators can be used in ecological monitoring of Sevastopol coastal waters for estimation the state of hydrobionts and their environment.