Heavy metal pollution and ecological risk assessment in sediments of Xiling Channel inland waterway of Guangdong province.

Abstract

Using the sediment monitoring data of five sections of the Xiling Channel inland waterway of the Pearl River Delta, and using Nemerow composite index, the coefficient of variation, and the index of geoaccumulation (Igeo) and the potential ecological risk index, this paper analyzed and assessed the heavy metal pollution of sediments. The results indicate that Cr reached mild pollution; Cu had a large degree of variation, and the changes of Cr and Zn were significant with fluctuation; the enrichment of heavy metals decreased as follows: Cd > Cu > Cr > Zn > Pb > Ni > Hg > As; Cd had the highest degree of enrichment and belonged to moderate pollution; the ecological hazard of heavy metals was Cd ˃ Hg ˃ Cu ˃ Pb ˃ As ˃ Cr ˃ Ni ˃ Zn, and Cd had the highest ecological hazard and was the main controlling factor of potential ecological risk. In conclusion, the sediments in Xiling Channel inland waterway were polluted by heavy metals to some extent, and cadmium was the main pollutant and had the largest potential ecological risk.