Abstract: Removing heavy metals or reducing metal concentrations in heavy metal-contaminated soils by hyperaccumulating plants has been proposed as one of the most promising green remediation techniques.Effects of phytoremediation of heavy metal-contaminated soils on following plants have rarely been investigated.A pot experiment was carried out to investigate effects of phytoremediation by manganese hyperaccumulating plants,Phytolacca americana,on phytotoxicity of a manganese mine tailings contaminated soil and metal accumulation of following plants Glycine max and Phaseolus radiatus therein.The soil in pots was planted first with P.americana seedlings,which were removed after one,two or three years and recorded as T-1,T-2,and T-3,respectively.The soil not planted with P.americana served as control.Then seeds of G.max and P.radiatus were sown into those pots.Phytotoxicity of the soil in the pots treated with P.americana became lower compared with that of the control.Phytoremediation of the contaminated soils decreased concentrations of Cd,Pb,Zn and Mn in the biomass of the two plants,G.max and P.radiatus,which promoted their growth.Phytotoxicity of the soil in the pots treated with P.americana was lower to G.max than to P.radiatus.In order to maintain a long-term sustainable vegetation on lands contaminated by manganese mine tailings,herbaceous legume such as G.max can be used to solve the problem of nitrogen deficiency in soils following 2-3 years of phytoremediation with P.americana.

Key words: phytoremediation, Phytolacca americana, Glycine max, Phaseolus radiatus