Effects of copper on growth and zinc and cadmium accumulation of Sedum plumbizincicola
铜对伴矿景天生长及锌镉吸收性的影响

Growth chamber hydroponics culture and glass house pot experiment were conducted to study the effects of copper on the growth of Sedum plumbizincicola plant and its accumulations of Zn and Cd.The results from the hydroponics culture showed that there was no significant difference on the growth and Zn and Cd concentrations of Sedum plant among the treatments of low solution Cu concentrations(0.31-50 μmol/L),but 100 μmol/L solution Cu inhibited plant growth and Cd and Zn accumulations in plant shoot.The glass house pot experiment results showed that sedum plant grew slowly in soil at low Cu(3.61 mg/kg) concentration,however,the addition of Cu promoted its growth.The application of 3 mmol/kg EDDS and 250 mg/kg Cu led the greater accumulation of Cu in plant,with the highest Cu concentration of 1 068 mg/kg,which may be responsible for plant injury and leaves fallen down.These results showed that low concentration of Cu benefits the plant growth and the phytoextraction of Zn and Cd from contaminated soil,but high soil Cu concentration inhibits plant growth and metals uptake.Therefore,more attentions should be paid on plant Cu toxicity when using Sedum plumbizincicola to remediate Cd and/or Zn contaminated soil with high concentration of Cu.