Distribution and contamination assessment of heavy metal in sediment of the Shaanxi reach, Weihe River

Sediments in five national controlling sections of Weihei river in Shaanxi province have been investigated for cadmium (Cd), lead (Pb), zinc (Zn), chromium (Cr), Nickel (Ni) and copper (Cu). The results demonstrated there were highly significant variations among different sampling stations for the concentrations of tested metals. There appeared obvious Zn and Pb enrichment in sediment in all the studied area. Cd was found enrichment in one section. In addition, Pb was found in high percentages in residual fraction and oxidizable fraction, posing less threat of release to water with changing environmental conditions.