摘要
针对上海市松江区某复垦工业地块表层土壤中8项重金属元素(镉、铅、铜、锌、镍、汞、砷、铬)污染特征及潜在生态风险开展了调查评估。结果表明,工业活动导致复垦工业地块表层土壤中铜、锌、砷、铬累积明显,部分区域重金属超标。砷的最大含量为农用地土壤污染风险筛选值的1.34倍,铜、锌、砷、铬的平均含量分别为上海市土壤环境背景值的1.07、1.08、1.09、1.36倍。重金属含量空间分布情况表明,锌、砷高含量区分布比较零散,其它重金属高含量区呈现区域性分布。根据地积累指数评价,复垦工业地块部分区域表层土壤样品存在不同程度的污染。镉、锌、汞、砷、铬达到轻度—中度污染,污染等级为1级,其中砷和铬的1级污染点位频率明显高于其它重金属。铜、铅、镍处于无污染等级。根据潜在生态风险评估,复垦工业地块部分区域表层土壤重金属处于中等风险水平,汞和镉为主要贡献因子。潜在生态风险空间分布情况表明,中等风险区主要分布在地块东部、南部。建议在开展土壤污染防治相关工作时,除将往年调查超标指标纳入跟踪调查外,也应重点关注汞和镉的含量变化及潜在生态风险,以全面保障区域农用地土壤环境质量和农产品质量安全。
Eight heavy metal elements (Cd,Pb,Cu,Zn,Ni,Hg,As,Cr) in surface soil of one reclaimed industrial site in Songjiang district of Shanghai were investigated to evaluate the pollution characteristics and potential ecological risk.The results showed that industrial activities resulted in significant accumulation of Cu,Zn,As and Cr in surface soil of the reclaimed industrial site,and heavy metals in surface soil exceeded the standards in some areas.The maximum content of As was 1.34 times the risk screening value for soil contamination of agricultural land,the average contents of Cu,Zn,As and Cr were 1.07,1.08,1.09 and 1.36 times the background values,respectively.In terms of spatial distribution of heavy metal contents,the higher contents of Zn and As were relatively scattered while the higher contents of other elements were zonal.For the geo-accumulation index,surface soil samples in some areas were contaminated to varying degree.Cd,Zn,Hg,As and Cr pollution reached mild ~ middle pollution grade and level-1,and the contaminated point frequency of As and Cr were higher than the rest heavy metals.Cu,Pb and Ni were in pollution-free grade.It can be learned from the potential ecological risk assessment that heavy metals in surface soil of some areas were in the middle ecological hazard,and Hg and Cd were the major contributing factors.The spatial distribution showed that the middle ecological hazard areas were concentrated in the east and south of the site.It is recommended that when carrying out work related to soil pollution prevention and control,in addition to considering the indicators that exceeded the standard in previous years into the follow-up investigation,we should also focus on Hg and Cd content and potential ecological risks,so as to comprehensively ensure the quality of the regional agricultural land soil environment and the quality and safety of agricultural products.
作者
张惠
ZHANG Hui(Shanghai Geotechnical Engineering Detecting Centre Co.,Ltd,Shanghai 200436,China)
出处
《上海国土资源》
2022年第3期105-110,130,共7页
Shanghai Land & Resources
基金
上海市规划和自然资源局科研项目。
关键词
复垦工业地块
表层土壤
重金属
污染特征
潜在生态风险
reclaimed industrial site
surface soil
heavy metals
pollution characteristics
potential ecological risk
