Trace Elements in Marsh Soils of the Pomor Coast of the White Sea

The soils of the sea coasts function on the contact of terrigenous runoff and the effects of seawater, which provides a unique geochemical environment. In part, the processes of migration and accumulation of elements can be provided by the processes of formation and oxidation of iron sulfides. The content and spatial distribution of trace elements in the soils of the marshes of the Pomor coast of the White Sea were studied. The work was carried out near the village of Kolezhma, Belomorsky district, Republic of Karelia. The study showed that the studied soils are characterized by an increased content of trace elements such as As and Se, which are usually associated with the presence of metal sulfides in marine sediments. The content of Fe was up to 27 300 ppm and Mn – up to 1500 ppm, which is generally typical for taiga landscapes. At the same time, the geochemical fate of Fe and Mn in coastal soils diverges, probably partly due to the participation of Fe in mineral transitions from sulfides to sulfates. Ni and Cr were present in soils in concentrations comparable to the zonal soils of the region. Only As and Se might be potentially toxic in the case of the use of the tombolo as hayfield.