Soils of Accumulative Coasts of the East Siberian Sea

— Thalassosols developing on the accumulative coasts of the East Siberian Sea include initial soils of regularly flooded tidal flats with sparse vegetation, episodically flooded marsh soils with different degrees of salinization, and maritime soils that are morphologically close to the zonal soils but are affected by salts transferred by wind with seawater drops and organomineral matter from the non-vegetated seashores. Weakly developed marsh soils have the initial features and structure of the marine sediments combined with the processes of salinization; sulfate reduction; gleyzation; cryogenic mass exchange; as well as the transfer, accumulation, and weak biochemical transformation of the raw organic matter. Soils with different degrees of salinization are formed on tidal marshes and are characterized by some redistribution of salts in the soil profile with weak accumulation of salts in the uppermost organic horizons and in the suprapermafrost layers along with pronounced sulfate reduction. Slightly saline organogenic and peaty gleyic soils predominate in the areas of sedge marshes. The majority of studied marsh soils form under the conditions of distinct cryogenic polygonal microtopography, waterlogging, and relatively shallow permafrost.