矿区土壤Pb的分布特征及植物修复应用性研究

对云南省某有色矿区采矿厂及选矿厂周围土壤Pb污染现状、土壤中Pb的形态分布特征及其植物有效性进行了分析.按照Tessier的重金属形态分级和浸提方法,Pb在土壤中主要以铁锰氧化物结合态及有机结合态为主,植物有效性较低.比较两样点土壤Pb活性,选矿厂高于采矿厂,这可能是由于Pb的来源不同.从土壤含Pb及植物有效态Pb含量来看,该矿区样点土壤Pb污染均较严重,开展污染修复工作势在必行.以植物体内Pb含量、地表上部有效富集系数及转移系数为指标,对20种植物对Pb的富集特性分析发现,类芦富集和转移Pb的能力较强,进一步研究价值很大.从土壤Pb的有效态含量及生态安全考虑,在该矿区进行土壤Pb污染的植物提取修复是可行的.

Characteristics of Pb Distribution in Soils Around Mine and Research on Phytoremediation Availability

Studies are conducted on the contamination situation of Pb in soils and its distribution and phytoavailability for a non-ferrous metal mine in Yunnan Province.According to distribution and extraction of heavy metals of Tessier,there exist two kinds of distribution of Pb in soils,Fe/MnOx-Pb and Org-Pb,and phytoavailability of Pb is low.The mobility of Pb in the mineral separation site is higher than that in the mining site,which is probably on account of the difference in origin of Pb.The contents of total Pb and phytoavailable Pb in soils show that the collected soils are seriously contaminated.Studies on the contents of Pb and bioaccumulation factors and transfer factors in the above ground for 20 plant samples indicate that Neyraudia reynaudiana(kunth) keng do well in accumulating and transferring Pb.Considering the content of phytoavailable Pb in soil and ecological safety,phytoextraction for Pb contamination in soils in the mine is applicable.