摘要
绿地土壤是城市生态系统的重要组成部分,随着城市化进程的加快,绿地中的重金属污染问题日益引起人们的重视。为查明天津市环城四区绿地重金属含量特征、空间变异特征及潜在生态风险,本文以环城四区200件绿地土壤样品为基础,对Cr、Ni、Cu、Zn、Pb、As、Hg、Cd等8项重金属指标进行测定,应用统计分析、对比分析及Hankanson生态风险指数法等进行探讨,结果表明:①绿地土壤中Hg和Cd的变异程度最高,与人类活动关系密切;Cu、Zn、As具有较大的变异性;Pb、Ni、Cr在土壤中分布均匀。②与天津市表层土壤背景值相比,Hg、Cd和Zn这3种元素明显富集,Cu、Pb、As、Ni与土壤背景值相差不大,Cr低于土壤背景值。③单一重金属的潜在生态因子Hg为强烈生态风险,Cd为中等生态风险。④潜在生态危害指数RI=241.42为中等生态风险,居住绿地的土壤重金属生态风险相对较高,Hg和Cd为主要的影响因素,贡献率分别为为65.79%和21.68%,须注意管控和生态保护。
Soil of green space is an important part of urban ecosystem,with the acceleration of urbanization,problems of heavy metal pollution in green space has attracted more and more attention.In order to find out the content characteristics,spatial variation characteristics and potential ecological risks of heavy metals in green space in the four districts around the city of Tianjin,8 heavy metals were determined and discussed by means of statistical analysis,comparative analysis and hankanson ecological risk index method,on basis of 200 collected samples in the four districts.The results showed that:①Hg and Cd belonged to the high degree of variability,which were closely related to human activities;Cu,Zn and As has a greater variability;Pb,Ni and Cr were evenly distributed in the soil.②Compared with the background value of topsoil in Tianjin,Hg,Cd and Zn were obviously enriched,Cu,Pb,As and Ni were similar to the background value of soil,and Cr was lower than the background value of soil.③Hg posing strong ecological risk and Cd posing medium ecological risk.④According to the statistics of potential ecological risk index,RI=241.42 is medium ecological risk.The ecological risk of soil heavy metals in residential green space is relatively the higher than others.Cd and Hg were the main influencing factors,more attention should be paid to control of contaminated plot and ecological protection.
作者
李硕
李宏伟
盛恭勇
刘永涛
程绪江
李明明
LI Shuo;LI Hongwei;SHENG Gongyong;LIU Yongtao;CHENG Xujiang;LI Mingming(Tianjin Institute of Geological Survey,Tianjin 300191,China;Lianhe Equator Environmental Impact Assessment Co.,Ltd.,Tianjin 300042,China;Henan Third Geological Exploration Institute Co.,Ltd.,Zhengzhou,Henan 450000,China)
出处
《矿产勘查》
2023年第5期811-817,共7页
Mineral Exploration
基金
天津市国土资源和房屋管理局项目“天津市中心城区周边环境地球化学调查”(国土房任[2015]3号)资助。
关键词
绿地
背景值
地球化学特征
潜在生态风险评价
天津
green space
background value
geochemical characteristics
potential ecological risk assessment
Tianjin City
