摘要
以钢铁企业周边工业遗留地块为研究对象,分析土壤4种重金属As、Pb、Hg、Cd污染分布特征,应用单因子污染指数法和地累积指数法量化As、Pb、Hg、Cd污染水平,利用正定因子矩阵模型(PMF)进行土壤重金属源解析.研究结果表明:As超《土壤环境质量建设用地土壤污染风险管控标准(试行)》(GB 36600-2018)第一类用地筛选值1.15倍,应采取风险管控或修复措施,As、Pb、Hg、Cd最大浓度值均高于背景值,受人类活动影响.As、Pb、Cd这3种元素两两之间显著正相关,Hg与As、Pb、Cd不存在显著相关性.单因子污染指数法计算结果表明,土壤重金属污染程度表现为As＞Pb＞Cd＞Hg.地累积指数法计算结果表明,As、Pb、Hg、Cd地累积指数平均值均小于0,但个别点位存在不同程度的污染.空间分布上,As、Pb、Hg、Cd在不同深度上主要呈现点状分布.研究区土壤重金属主要来自化石燃料燃烧源、道路交通源及工业污染源、农业源,其贡献率分别为68％、26％、6％.
Abstract
This article took the industrial legacy site around a certain steel enterprise as the research object,analyzed the distribution characteristics of four heavy metal As,Pb,Hg and Cd in soil,applied single factor pollution index method and land accumulation index method to quantify As,Pb,Hg and Cd pollution levels,and used positive definite factor matrix model(PMF)for soil heavy metal source analysis.The research results indicated that heavy metal As exceeded the screening value of Class Ⅰ land of"Soil environment quality risk control standard for soil contamination of development land"(GB 36600-2018)by 1.15 times,and risk control or remediation measures should be taken.The maximum concentrations of As,Pb,Hg,and Cd were all higher than the background values,indicating human interference.As,Pb,and Cd had a significant positive correlation with each other,while there was no significant correlation between Hg and As,Pb,and Cd.The calculation results of the single factor pollution index method indicated that the order of soil heavy metal pollution degree was As＞Pb＞Cd＞Hg.The calculation results of the land accumulation index method showed that the average values of As,Pb,Hg,and Cd land accumulation indexes were all less than 0,but there were varying degrees of pollution at individual points.In terms of spatial distribution,As,Pb,Hg,and Cd mainly exhibited a point-like distribution at different depths.It was found that soil heavy metals in the study area mainly came from fossil fuel combustion sources,road traffic sources and enterprise pollution sources,and agricultural sources,with contribution rates of 68％,26％,and 6％,respectively.
基金项目
北京市自然科学基金面上项目(8222045)
北京市科学技术研究院创新培育项目(2023G-0007)
NETL
NSTL
万方数据