Geoecological conditions in the Baltic sea in 2017

Abstract

In 2017, comprehensive geological, geophysical, hydrological and hydrochemical researches were conducted in the South-Eastern Baltic Sea and the Gulf of Finland. 1775 nautical miles of surveys were conducted using multibeam echosounder and profiler. Surface bottom sediments (156 samples), the upper undisturbed layer of pelitic sediments and bottom water (15 samples), 2 cores were taken. Laboratory analyzes were performed on pH (189), concentration of oxygen (246), suspended matter (286) and oil products (110). Microplastic was also collected in the water (118) and bottom sediments (45). Conducting comprehensive research in the South-Eastern Baltic Sea allowed us to record the weakening of the Major Baltic Inflow effects, followed by changes in the environmental conditions of the region. Geological surveys in the Gulf of Finland expanded the coverage area of the bottom of multibeam surveys and contributed to the refinement of the formation processes of linear and circular transgressions at the bottom.