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

Abstract

Sea coastal soils are functioning on the contact of terrigenous runoff and the seawater impact, which provides a unique geochemical environment. Migration and accumulation of elements can be partially promoted by the formation and oxidation of iron sulfides. We studied the content and spatial distribution of Fe, Mn and trace elements in the marsh soils of the Pomor coast of the White Sea. The work was carried out near the village of Kolezhma, Belomorsk district, Republic of Karelia. The study revealed the elevated concentrations of trace elements in these soils, such as As and Se, which are usually associated with metal sulfides in marine sediments. A high content of Fe and Mn was registered, i.e., up to 27 300 and 1500 ppm, respectively, which is typical for taiga landscapes. At the same time, the geochemical fate of Fe and Mn is different in coastal soils, probably partly due to the participation of Fe in mineral transitions from sulfides to sulfates. Such microelements as Ni and Cr are present in the soils in concentrations comparable to the background concentrations in the regional zonal soils. Only As and Se may be potentially toxic, if tombolo is used as a hayfield.