Methane and hydrogen sulfide in the bottom sediments of the estuaries of the Azov-Black Sea basin

In the summer-autumn period of 2013-2018, studies were conducted on the distribution of methane (CH4) and hydrogen sulfide (ΣH2S) in the estuaries of the Azov (Yeisky, Beisugsky, Sladky, Kurchansky and Akhtanizovsky) and Black (Vityazevsky, Kiziltashsky and Bugazsky) seas characterized by different salinity. For the first time, to characterize the conjugate distribution of CH4 and ΣH2S in the bottom sediments of aquatic ecosystems, the "methanization" coefficient was used, which is the percentage of CH4 from the sum of concentrations (in mg/g) of reduced gases - ΣH2S and CH4. Concentrations of CH4 and ΣH2S in bottom sediments of desalinated estuaries with water salinity from 0,26 to 8,20% (Sladky, Akhtanizovsky and Kurchansky) vary from 0,01 to 114,34 μg/g of wet sediment and from