铅锌尾矿区15种植物的生长及对重金属的吸收积累  

Growth and Heavy Metal Uptake of 15 Plant Species Grown in Lead/Zinc Mine Tailings

作　　者：陈益泰[1] 施翔[1] 王树凤[1] 李江川[1] 孙宇剑 

机构地区：[1]中国林业科学研究院亚热带林业研究所,富阳311400 [2]浙江省富阳市林业局,富阳311400

出　　处：《林业科学》2012年第12期22-30,共9页Scientia Silvae Sinicae

基　　金：国家林业局948项目(2006-4-06);浙江省科技厅重大项目(2006C12065);浙江省科技厅社会公益项目(2011C23036;2011C22003)

摘　　要：在废弃的铅锌尾矿库进行人工植被恢复试验,对3年生15种植物修复铅锌矿尾矿的潜力进行评价。结果表明:参试植物出现叶片黄化、提早落叶或停止生长现象。株高和基径增长率、根系生长、生物量等种间差异显著。根系生长深度受到抑制,最大侧根长、细根长度比例和根系生物量比重有不同程度增加。其中桤木、紫穗槐、截叶胡枝子、紫花苜蓿4种固氮植物叶片受害轻微,均有根瘤出现。火炬树、夹竹桃叶片受害程度较低,相对生长率较高,单株生物量较大。植物对土壤重金属的吸收积累因植物种类、部位、金属种类不同而不同。植株不同器官Pb和Zn浓度高低总趋势为根>茎,部分树种Zn浓度表现为茎>根。在15种参试植物中,截叶胡枝子单位面积地上部Pb和Zn积累量均最高,分别为65,199mg·m-2,其次为紫穗槐,Pb和Zn积累量分别为43,127mg·m-2。筛选出综合表现较佳的紫穗槐、截叶胡枝子、火炬树、夹竹桃、桤木、盐肤木、紫花苜蓿和加拿大紫荆等8种植物,它们是铅锌尾矿库植被恢复的适宜材料,其中固氮植物应用潜力较大。A field experiment on vegetation restoration was carried out in the abandoned lead-zinc tailings for 3 years with 15 plant species to evaluate their potential adaptation to the tailings. Plant species expressed different tolerance to stress of the tailings. Most species appeared the heavy metal-induced etiolation, defoliation, or growing stopped. There were significant differences in the growth rate of height and base diameter, root growth, and biomass among the species. The mine tailings reduced the root distribution depth, and stimulated the max length of lateral roots, the fine root ratio, and increased to different extents the mass allocation proportion to roots in all species. Four nitrogen-fixed species, Alnus cremastogyne, Amorpha fruticosa, Lespedeza cuneata, and Medicago sativa, suffered from mild damage, and root nodules appeared in their roots. In addition, Rhus typhina and Nerium indicum had higher tolerance, which kept higher relative growth rate and biomass. The results showed that accumulation of lead （Pb）, and zinc （Zn） differed dependent on plant species, their organs, and the heavy metals. Generally, most plant species had higher concentrations of Pb and Zn in roots than that in shoots, while some of tree species had higher Zn concentrations in shoots than that in roots. Among the 15 species, L. cuneata had the highest contents of Pb and Zn in shoots in per square meter of ground （65 and 199 mg·m-2, respectively）. A. fruticosa had the second high Pb and Zn contents, reaching to 43 and 127 mg·m-2, respectively. Based on overall performance we selected eight species candidate： A. fruticosa, L. cuneata, R. typhina, N. indicum, A. cremastogyne, R. chinensis, M. sativa, and Cercis canadensis, which would be suitable for the vegetation restoration in lead and zinc mine tailings, especially the nitrogen-fixing species.

关 键 词：尾矿库 植物修复 生长 重金属积累 综合评价 

分 类 号：S718.56[农业科学—林学]