Regional patterns of element contents in the organic horizon of podzols in the central part of the Barents region (Finland, Norway and Russia) with special reference to heavy metals (Co, Cr, Cu, Fe, Ni, Pb, V and Zn) and sulphur as indicators of airborne pollution

In 1995, the Geological Surveys of Finland (GTK) and Norway (NGU) and the Central Kola Expedition (CKE) carried out an ecogeochemical mapping programme across one of most heavily damaged areas in Europe, i.e., the western half of the Kola Peninsula, and contiguous areas in northern Finland and Norway. The study included not only media such as moss and podzol profiles but also samples of the humus layer for more than 650 sampling sites. The nature of organic material, i.e., humus layer, depends on the vegetation, climatic conditions and the overburden. The element concentrations found in humus are dual in origin, reflecting anthropogenic input as well as local geology. The anthropogenic input is clearly seen on the map of Factor 1 (Ni, Co, Cu, As, Ni, Cd and Pi). The influence of geology can be seen clearly on the factor loading maps for Factor 2 (Fe, Cr, V, Sb) and, to a lesser extent, those for Factors 4 (Sr, Ca, P) and 5 (Y, Th, Ag, Al). Factor 3 (Rb, Tl, S) combines all those elements whose concentrations increase towards the south, and can be attributed to the zonation of vegetation. Factor 6 (B, K, Mg) can mainly be interpreted as a marine factor. The areas of high loadings of heavy metals have not expanded; the areas of maximum loadings have remained roughly the same for several years as compared to results obtained previously in the same area. The heaviest loadings occur in the area within a radius of 50 to 100 km of the emission source. (C) 2000 Elsevier Science B.V. All rights reserved.