Results of Black Sea algal viruses monitoring

Abstract

Search, isolation, study and monitoring of Black Sea algal viruses, new to science or new for the Black Sea ecosystem, has been carried out at the Sevastopol Institutes of for over 18 years. During this time more than 300 strains of algal viruses were isolated to seven species of microalgae and to one species of cyanobacteria from more than one thousand different samples (sea water, bottom sediments, mussels and fish). The purpose of the work is to summarize and analyze the results of long-term monitoring of the Black Sea viruses of microalgae (the stable Tetraselmis viridis and the demanding for environmental conditions Phaeodactylum tricornutum), that are two bioindicators of the environmental situation, from water samples of three Sevastopol bays, that differ in ecological status. The obtained data served as the basis for the assumption of relatively good ecological status in the studied water areas of Sevastopol bays in 20072008 and 20172020, and in 20022003, 2006 and 2015 about bad environmental (ecological) status. An analysis of the results indicates that studied two bays staying in relatively well ecologically status are characterized by isolation of the maximum number of viral strains of two bioindicatoral microalgae with a numerical predominance of viral strains of the P. tricornutum (environmentally demanding microalgae), in comparison with the same indices in a closed bay with bad ecologically status and staying in anthropogenic load. A shift of two months in the spring seasonality (in January February) of algal viruses in 20192020 was noted.