摘要
以湖南某铅锌冶炼厂周边土壤为研究对象,运用地统计学和多元统计方法,分析土壤中Cd、Pb、As含量和空间分布特征,探究其来源,并对该区域进行潜在生态风险评价。结果表明:Cd、Pb、As的平均含量分别为434.78、2 908.27、320.48 mg/kg,远超过国家标准限值;从土壤重金属含量空间分布图可以明显看出:Cd、Pb、As空间分布特征极为类似,在废渣堆场和住宅区污染严重且较集中,污染程度为:废渣堆场>住宅区>闲置区>菜地;各重金属元素间相关性结果表明,3种重金属元素具有同源性,而聚类分析则显示,Cd和As的同源性更近,其主要来源为冶炼厂飘落的烟尘和冲刷上来的湘江底泥;潜在生态风险评价结果表明,在该区域除菜地存在一个低值中心外,其余部分均存在极严重的生态风险,尤以废渣堆场生态风险最为严重。
The soil around a lead and zinc smelter in Hunan was taken as the research object. Geostatistics and multistatistics were applied to investigate distribution characteristics of Cd, Pb, As. Then the sources of three elements were explored and the potential ecological risk assessment of the region was conducted. The results indicate that average concentrations of Cd, Pb and As are 434.78, 2 908.27, 320.48 mg/kg, respectively, far exceeding their corresponding limits in National Soil Environmental Quality Standard. Results of spatial distribution maps show that there was a strong correlation between Cd, Pb and As and heavy polluted spots were concentrated in the residue deposit and residential areas, with pollution levels in the descending order as residue deposit residential areas unused areas vegetable field. The analysis of correlation among heavy metals elements indicate that Cd, Pb and As have homology. The cluster analysis show that Cd and As have more closer homology, and they are mainly from the smelter dust and sediment of Xiangjiang River. The potential ecological risk assessment result indicate that except vegetable field with a low value center, soils in other place were engaging in a severe potential ecological risk, especially residue deposit, where the potential ecological risk was the most serious.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2016年第2期186-192,共7页
Environmental Science & Technology
基金
湖南省科学技术厅科技计划(2014SK3172)
长沙市科技计划重点项目(k1403043-31)
湖南省科技重大专项(2012FJ1010)
关键词
重金属
潜在生态风险评价
空间分布
源解析
heavy metal
potential ecological risk assessment
spatial distribution
source apportionment
