SCIENTIFIC EDUCATIONAL CENTER science idea

According to the conducted research, climatic changes that have caused a significant increase in temperature and salinity of the upper hundred-meter layer of the Black Sea increase the risk of alien species, which can cause a sharp degradation of the entire Black Sea system due to the deterioration of the living conditions of local species of living organisms. This conclusion was reached by scientists of the P.P. Shirshov Institute of Oceanology of the Russian Academy of Sciences on the basis of comprehensive hydrophysical and environmental monitoring conducted annually since 2009 on the basis of the Southern Branch of the IO RAS in Gelendzhik. The Black Sea, which is a body of water with a very thin active layer, is quite vulnerable to any external influences, including changes in climatic conditions and anthropogenic impact. Favorable conditions for the vital activity of organisms are available only in the upper layer with a thickness of 100-150 m, where oxygen is present. The main water column, starting from a depth of 150 m and up to the bottom (approximately 2000 m), is a lifeless hydrogen sulfide medium. Such specific conditions are determined by the presence of a sharp difference in salinity/density, blocking vertical mixing and oxygen transport into the deep layer of the Black Sea. The warming of the regional climate observed over the past 25-30 years, expressed in an increase in the temperature of the upper layer by 2 ° C, and a significant increase in water salinity over the past 15 years, lead to a further decrease in the thickness of the oxygen layer and, accordingly, to the rise of the hydrogen sulfide contamination zone. In addition, there is an increase in cyclonic wind vorticity and the intensity of geostrophic circulation, as well as a decrease in freshwater runoff and precipitation over the Black Sea. Such climatic changes increase the risks of the introduction of more thermophilic Mediterranean species into the Black Sea ecosystem, which can lead to catastrophic changes similar to those that occurred in the late 80s of the last century due to the introduction of Mnemiopsis leidei into the Black Sea. Its massive reproduction caused a sharp degradation of the entire Black Sea ecosystem, which partially recovered only two decades later. On the other hand, increased anthropogenic stress caused mainly by industrial and economic activity on the shore and in coastal areas of the sea increases pollution and eutrophication of the waters of the shelf zone and can also lead to changes at the ecosystem level. This factor has so far had a tangible negative impact on the Black Sea ecosystem in the "hotbeds" of pollution – near large coastal cities, in ports, but the risks that water pollution, including oil pollution, will reach a critical level at some point are steadily increasing. "The systematic study of the impact of changing climatic conditions and anthropogenic stress on the ecosystem of the Black Sea is the most important task of modern comprehensive scientific research. This task should be solved, first of all, by conducting year-round shipboard and automated (remote and contact) monitoring of key parameters of the Black Sea ecosystem, both in the coastal zone and in deep-sea areas. It is these tasks that are being solved at the Gelendzhik hydrophysical landfill, operating on the basis of the Southern Branch of the Institute of Oceanology of the Russian Academy of Sciences," said Andrey Zatsepin, Head of the Laboratory of Experimental Ocean Physics of the IO RAS, Doctor of Physico–Mathematical Sciences.

PHOTO: a working model of an automatic multisensory profilograph probe with automatic data transmission, designed for long-term monitoring of hydrophysical and bio-optical parameters of the aquatic environment. Photo author: A.G. Zatsepin

Information and photos provided by the press service of the P.P. Shirshov Institute of Oceanology of the Russian Academy of Sciences

Information taken from the portal "Scientific Russia" (https://scientificrussia.ru /)