ELEMENT CONCENTRATION AND PARTITIONING OF LOESS IN THE HUANGHE (YELLOW-RIVER) DRAINAGE-BASIN, NORTH CHINA

Loess samples from the middle reaches of the Huanghe (Yellow River) are analysed to determine the concentration and partitioning of Fe, Mn, Cu, Pb, Zn, Cr, Co, Ni, Na and K. Very similar element concentrations are observed between the different areas of the Loess Plateau. The relatively low trace-element levels of loess as compared with the mean value of world soils are related to their wind-borne origin and intense erosion over the Loess Plateau. Most of the studied elements are associated with mineral fractions (carbonate + aluminosilicates) which account for 70-95% of total element concentrations. Low concentrations in the labile fractions suggest the weak element bioavailability to crop growth in this region.