Evaluating heavy metal contamination of riverine sediment cores in different land-use areas

Anthropogenic activities are regarded as the main sources of heavy metal pollution,yet few studies have investigated the effects of land-use setting on heavy metal accumulation in riverine sediments.Based on both total contents and geochemical fractions,heavy metal pollution,risk and toxicity were determined in riverine sediment cores from different land-use areas(mountain area-MA,farm area-FA,city area-CA,and industrial area-LA)of the Yang River Basin in North China.The results showed that FA had higher contents of riverine sedimentary Cu;CA had higher contents of Cd;LA.had higher contents of both Cd and Zn.Most riverine sediments from FA and IA were contaminated with the investigated metals,although these concentrations were evaluated to have low potential ecological risk and no toxicity to benthic organisms.However,a high proportion of Cd in the B1 fraction of riverine sediments in IA indicating high risk should receive more attention.The B1 fraction largely determined the contamination,risk and toxicity levels associated with heavy metals in the riverine sediments of the Yang River Basin.