Distribution and Genesis of Aliphatic Hydrocarbons in Bottom Sediments of Coastal Water Areas of the Crimea (the Black and Azov Seas)

The aim of the article is to assess the level of aliphatic hydrocarbon (AHC) contamination in bottom sediments of the Azov–Black Sea coast of the Crimea, as well as to identify potential sources of its formation. Bottom sediment samples obtained from 19 stations during the research cruise of the R/V “Professor Vodyanitsky” (June 2020) were used as the material for this investigation. Sampling stations were located along the coast of the Crimean Peninsula and the Caucasus coastlines (the Black and Azov Seas). N-hexane extracts of sediments were studied by gas chromatography to determine the AHC amount and composition. It was established that AHC concentrations in the study area varied from 1.30 to 127.8 mg/100 g. Generally, bottom sediments of the Black and Azov Seas were characterized by low AHC contents, while increased AHC contents were found in the outer harbor of Sevastopol and Yalta regions. To identify potential hydrocarbon sources, various hydrocarbon markers were used. In most of the study areas, n-alkane composition was determined by similar sources of inputs and organic compound transformation. At the same time, oil pollution linked with use of fuel was recorded almost everywhere.