Content of Acid-Soluble Copper and Zinc in Background Soils of Komi Republic

Geochemical features of copper and zinc in soils of background landscapes of northeastern European Russia have been revealed. Soils of accumulative landscapes are enriched with copper and zinc compounds compared to those of eluvial landscapes. Humus horizons serve as a geochemical barrier for elements. Analysis of the sorption parameters of humic acids (HAs) shows that the actual content of the studied heavy metals (HMs) in soils is far from the maximum sorption capacity. The contribution of HAs to the total sorption of metals makes up 4% for copper and 21% for zinc. The distribution of HMs among the genetic horizons is more contrast in loamy automorphic soils than in sandy semihydromorphic and hydromorphic soils. Paired correlations have been revealed between the contents of copper and zinc in sandy and loamy soils, which points to the similarity of their biogeochemical migration in landscapes. An actual database has been created, which is foundational to schematic maps of the spatial distribution of elements in background soils. The geochemical assessment of the environmental status of soils has allowed establishing norms for the regional background contents of copper and zinc in taiga and tundra soils.