Bioaccumulation of heavy metals by wild plants growing on copper mine spoils in China

In the present study, the wild vegetation associated with copper (Cu) mine spoils was investigated at five sites in eastern China. A collection of 49 plant species (members of 48 genera and 30 families) was studied. All the aboveground parts (shoots or leaves) of the samples were analyzed for total concentrations of Cu, zinc (Zn), lead (Pb), and cadmium (Cd). The average Cu concentrations in plants at different deserted mining sites showed an increasing trend with the age of mine spoils. Commelina communis, Polygonum macrathum, Elsholtzia haichowensis, and Arthraxon prionodes collected at different sites had significantly higher concentrations of Cu than other plant species, with the highest Cu concentrations of 361, 286, 186, and 181 mg kg-1, respectively. These plant species also had significantly higher Zn, Pb, and Cd concentrations than other species studied. Results suggest that these plants could be good candidates for use in the revegetation and phytoremediation of copper mine spoils.