Natural and man-induced sources of elements supplied to bottom sediments in water bodies of the Altai territory

Distributions of Be, B, Cd, Cu, Zn, Pb, Mo, Cr, Ni, Co, Sb, Mn, Mg, and Hg have been studied in bottom sediments of 67 lakes, oxbows, and man-made ponds of the Altai Territory. The water bodies occur in different landscape-climatic zones and are fed by both flood and ground waters. The main factor of the formation of geochemical composition of sediments is the natural supply of trace elements with solid and liquid runoffs from the water-catchment areas, which results in different levels of concentration of elements in the bottom sediments of water bodies situated in different zones. The vertical section of the sediments of some lakes distinctly shows an increase in concentrations of the most of heavy metals from bottom to top. In some cases this phenomenon is due to natural factors, while in the others, man-induced ones. Though of the West Siberian regions the Altai Territory occupies one of the last places in the amount of industrial atmospheric wastes, the cumulative effect of global, regional, and local sources has resulted in a 1.5-3-fold increase in the contents of Cd, As, Sb, Pb, Zn, and Hg in the sediments for the last 100 years.