红皮云杉不同器官对土壤重金属的富集特征

Enrichment Characteristics of Soil Heavy Metals in Different Organs of Picea koraiensis

为了解不同污染等级下红皮云杉不同器官的富集特征,运用室外采样和室内测定相结合的方法,测定了红皮云杉树叶、树枝、树皮、树根和根际土壤中3种重金属元素(Pb、Cd、Cr)的含量。在污染等级1中,各器官重金属含量大小顺序为树皮>树枝>树根>树叶,在污染等级2中,各器官重金属含量大小顺序为树皮>树根>树枝>树叶。各器官对Cd、Cr和Pb的富集能力为树皮>树枝>树根>树叶。各重金属元素含量在红皮云杉中的总趋势为Cr>Pb>Cd,富集能力总趋势为Cd>Cr>Pb,反映出红皮云杉对Cd的低吸收高富集能力。随着土壤重金属污染等级的增加,红皮云杉对Cd和Cr的富集能力增加。单株红皮云杉不同重金属元素积累量为Cr>Pb>Cd,富集效能为树根>树枝>树叶>树皮,树根对各重金属元素的积累量明显高于其他器官。因而,红皮云杉可以作为对土壤中Cr、Pb污染场地进行修复和治理的备选树种。

To understand the enrichment characteristics of different organs of Picea koraiensis in different pollution levels,the contents of three heavy metal elements(Pb,Cd,Cr)in leaves,branches,bark,roots and rhizosphere soil of Picea koraiensis were determined by the combination of outdoor sampling and indoor measuring.The results show that bark has the highest content of heavy metals.In general,in pollution level 1,heavy metal content of each organ is bark>branch>root>leaf.In pollution level 2,heavy metal content of each organ is bark>tree root>branch>leaf.The enrichment ability of each organ to Cd,Cr and Pb is bark>branch>root>leaf.The general trend of the content of heavy metals in the Picea koraiens is Cr>Pb>Cd and the general trend of enrichment ability is Cd>Cr>Pb,which reflects the low absorption and high enrichment ability of Picea koraiens to Cd.With the increase of soil heavy metal pollution level,the enrichment ability of Picea koraiensis to Cd and Cr increase.The accumulation of different heavy metals in the single Picea koraiensis is Cr>Pb>Cd,and the enrichment efficiency is roots>branches>leaves>barks.The accumulation of heavy metals in roots is significantly higher than that of other organs.Therefore,Picea koraiensis can be used as an alternative species for the restoration and treatment of Cr and Pb contaminated sites in the soil.