Bioavailability and toxicity of heavy metals in a heavily polluted river, in PRD, China.

The research is designed to explore the SEM-AVS concept as a tool to assess bioavailability and toxicity of heavy metals in heavily polluted river sediments. The value of AVS and SEM is in a high level and only a few benthic invertebrate are found. Abundance of benthic invertebrate has significant correlation with SEM/AVS (r= -0.913, p<0.01) and SEM-AVS (r= -0.725, p<0.05). The analytical results of MDS (Non-matric Multi-dimensional Scaling) analysis indicate the benthic community structures of seven among nine stations where the SigmaSEM(5)-AVS<0 are similar. The two facts indicate the SEM-AVS concept also is useful to heavily polluted river sediments.