开阳磷矿10种木本植物叶片重金属富集特征

Enrichment characteristics of heavy metals in leaves and soil of 10 woody plants in Kaiyang phosphate mine

植物对重金属具有一定的吸附能力,植物修复是生态修复不可或缺的一部分,利用植物减缓和治理重金属污染具有重要意义。选取开阳磷矿马路坪矿区生命周期较长的木本植物及其土壤作为研究对象,探究木本植物受Cu、Zn、Pb、Cd、As等5种重金属污染土壤的效应,对植物重金属含量及其富集特性进行研究分析,筛选出累积重金属的植物,作为矿区生态修复的优势植物,获得如下的主要研究结论:(1)植物叶片中Zn最高,5种重金属元素含量趋势为Zn>Cu>Pb>Cd>As。Zn含量较高的有马尾松(Pinus massoniana)、楸树(Catalpa bungei)、二球悬铃木(Platanus acerifolia(Aiton)Willdenow)、杉木(Cunninghamia lanceolata);Cu含量较高的有二球悬铃木、楸树;Pb含量较高的有杉木、马尾松、核桃(Juglans mandshurica)。Cd含量较高的有马尾松、刺槐(Robinia pseudoacacia L.)、盐肤木(Rhus Chinensis)。As含量较高的有刺槐、二球悬铃木。(2)马尾松、楸树、二球悬铃木可以作为Zn污染严重区的修复树种;二球悬铃木、楸树可以作为Cu污染严重区的修复树种;马尾松、杉木、核桃可作为Pb污染严重区的修复树种;马尾松、刺槐、盐肤木可以作为Cd污染严重区的修复树种,刺槐、二球悬铃木可以作为As污染严重区的修复树种。(3)土壤与植物中Cu、Zn、Pb、Cd、As等5种重金属之间的关系较为密切,具有相似的污染来源。

Plants can absorb heavy metals,phytoremediation is an indispensable part of ecological remediation,it is important to use plants to mitigate and control heavy metal pollution.To bridge the gap,the contents of copper(Cu),zinc(Zn),lead(Pb),cadmium(Cd),and arsenic(As)in soils and woody plants surrounding Maluping Base,Kaiyang Phosphorous Mining Corporation(Guiyang,China)were investigated.Then,phytoaccumulators were selected for providing reference for the phytoremediation of metal-contaminated soils.Our results suggest that based on determination of heavy metals in plant leaves arranged in descending order are Zn,Cu,Pb,Cd,As,and indicate a single source for them since their concentrations in either soils or plants are closely correlated.Besides,high contents of Zn for Pinus massoniana,Catalpa bungei,Platanus acerifolia(Aiton)Willdenow,and Cunninghamia lanceolata,large concentrations of Cu in Platanus acerifolia(Aiton)Willdenow,and Catalpa bungei,Pb accumulation within Cunninghamia lanceolate,Pinus massoniana,and Juglans mandshurica were measured.Additionally,it is shown that plants amassing Cd include Pinus massoniana and Robinia pseudoacacia L.,and Rhus Chinensis,and that Robinia pseudoacacia L.and Platanus acerifolia(Aiton)Willdenow readily takes up As.Therefore,the aforementioned plants can be regarded as the accumulators of their corresponding contaminants in soils.