Abstract: In view of the problem of heavy metals in river sediments, the contents and spatial distribution of organic matter, total nitrogen, total phosphorus and six heavy metals (Cr, Ni, Cu, As, Cd, Pb) in surface sediments were analyzed, which were acquired from Chaohu small basin. The sources of heavy metals were analyzed by the method of heavy metal enrichment coefficient and principal component analysis, and the ground accumulation index and potential were utilized. The ecological risk of heavy metals was evaluated by ecological hazard index. The results showed that the average contents of organic matter, total nitrogen and total phosphorus in surface sediments were 162 g·kg^-1, 3707.2 mg·kg^-1, 2007.4 mg·kg^-1.The average contents of Cr, Ni, Cu, As, Cd and Pb were 51.66, 22.97, 36.41, 7.68, 0.40, 33.14 mg·kg^-1, respectively. The contents of Cu, Cd and Pb were 1.73, 6.01 and 1.26 times higher than the background values of surface soil in Anhui Province. Cu, Cd, Pb in the sediments have varying degrees of enrichment, and they are closely related to human activities. The degree of Cd pollution in sediments is high, and the potential risk grade of heavy metals is medium, but the overall environmental pollution is mild.

Key words: environmental engineering, source apportionment, sediment, heavy metals, pollution load index, potential ecological risk