双穗雀稗重金属耐性种群在铅锌尾矿生长的野外实验研究(英文)

Use of Tolerant Population of P.distichum for Revegetation of a Pb/Zn Mine Tailings at Lechang: Field Experiment

利用双穗雀稗 (Paspalumdistichum)的重金属耐性生态型 ,结合土壤、垃圾和石灰改良尾矿 ,在广东乐昌进行了为期一年的尾矿植被重建的野外试验 .重金属毒性和极端贫瘠是乐昌铅锌尾矿植物定居的限制因子 .野外试验第 1次收割结果表明 (3个月 ) ,双穗雀稗可以在乐昌铅锌尾矿正常生长 ,而尾矿覆盖 5cm的土壤或垃圾则可大幅度提高它的生物量 .施用石灰不仅促进植物的生长 ,同时可抑制植物对重金属的吸收 .第 2次收割结果表明 (1年 ) ,除了TDL处理 (尾矿 +5cm垃圾 +石灰 )双穗雀稗的生物量较第 1次收割有着极显著的提高 ,但各处理组 (尤其是TDL处理 )植物体内的重金属含量普遍有所降低 .实验证明利用耐性植物可在经轻度改良的尾矿上成功定居 .

A field trial was conducted on Lechang Pb/Zn mine tailings at Shaoguan, Guangdong Province, to evaluate the growth of a metal tolerant population of Paspalum distichum on Pb/Zn tailings amended with soil and domestic refuse. Chemical analysis indicated that the toxic level of heavy metals (Pb, Zn, Cu and Cd) and deficiency of major nutrients (N, P, K and organic materials) were the major constraints of the tailings for plant establishment. In the first three months, P. distichum could successfully grow on pure tailings, but the addition of soil and domestic refuse significantly improved growth of the grass, the application of limestone not only improved plant growth, but also inhibited the uptake of heavy metals by plants. The second harvest after one-year growth indicated that there was significant increase of biomass in TDL treatment (tailings+domestic refuse+limestone) compared with the first harvest. Generally, there were evident decreases of heavy metals contents in plant in the second harvest. Results presented here demonstrated that use of tolerant species together with waste materials might be a cost-effective method for revegetation of mine tailings.