Oxygen and Sulfides in Bottom Sediments of the Coastal Sevastopol Region of Crimea

Spatial variations in the distribution and fluxes of dissolved oxygen and sulfide in bottom sediments of Omega and Sevastopol bays have been studied. The results of analysis reveal that the distribution of dissolved oxygen and sulfide in pore water depends mostly on seasonal variations in the oxygen concentration in bottom water, grain size, the organic carbon content in bottom sediments, and, additionally for Sevastopol Bay, the iron content. The oxygen flux at the bottom of Sevastopol Bay is 20 times larger in winter–spring compared to that of Omega Bay. Anaerobic conditions in Sevastopol Bay sediments are observed much closer to the surface, with their subsequent development in bottom water.