锑矿区构树富集重金属的特性研究

为探索构对重金属的富集特征，分别选择生长于严重Sb、As、Cd、Hg污染和无重金属污染林地的构树，研究结果表明：锑矿区重金属污染地构树与非重金属污染地构树各器官的生物量与构成没有差异。锑矿区重金属污染地与非重金属污染地构树根、枝、茎、叶器官富集重金属Sb、Pb、Cd、Hg、As、Cu、Zn的量有极显著差异，构树具有较强的累积多种重金属的能力，为复合富集重金属的木本植物，其富集的重金属主要为Sb、Zn、Pb、As。在重金属污染的锑矿区构树根、枝、茎、叶各器官累积重金属Sb、As、Pb的顺序为：叶﹥枝﹥茎﹥根，累积Zn的顺序为：叶﹥枝﹥根﹥茎。重金属Sb、Zn、Pb、As主要富集在构树的叶、枝部。 锑矿区重金属污染地构树整株累积的Sb为155.85 mg?kg-1，Zn为150.12 mg?kg-1，Pb为37.56 mg?kg-1，As为18.9033 mg?kg-1，其中85%的重金属累积在构树的地上部分，且60%以上累积在构树的叶部。构树是锑矿区重金属污染地较为理想的生态修复与植被恢复的木本植物。

Study on the Characteristics of Heavy Metal Accumulation in Broussonetia papyrifera in an Antimony Mine

In order to investigate the phenomenon of bioaccumulation of heavy metals in Broussonetia papyrifera,we selected plants which grew in the forests with or without serious heavy metal （Sb,As,Cd,and Hg） contamination.Our findings showed no difference in the biomass and structures of various organs between the Broussonetia papyrifera plants in the heavy-metal contaminated locations in the antimony mine area and uncontaminated.The accumulation amounts of Sb,Pb,Cd,Hg,As,Cu,and Zn in the roots,branches,stems,and leaves of Broussonetia papyrifera plants showed very significant difference between the contaminated and uncontaminated locations.Broussonetia papyrifera is a woody plant that has a strong capacity for accumulating various heavy metals such as Sb,Zn,Pb,and As.The sequence in which the heavy metals such as Sb,as,and Pb accumulate in the roots,branches,stems,and leaves of Broussonetia papyrifera in the contaminated locations was leaves branches stems roots,and the sequence of Zn-accumulation was leaves branches roots stems.The amounts of Sb,Zn,Pb,and as accumulated by whole plants of Broussonetia papyrifera in the contaminated locations were 155.85 mg/kg,150.12 mg/kg,37.56 mg/kg,and 18.9033 mg/kg,respectively.Of these amounts,85% of heavy metals were accumulated in the aerial parts of Broussonetia papyrifera,and more than 60% were accumulated in the leaves.These findings showed that Sb,Zn,Pb,and as accumulate mainly in the leaves and branches of Broussonetia papyrifera.Broussonetia papyrifera could be the ideal candidate for ecological and vegetation restorations in the locations contaminated by heavy metals in antimony mines.