某燃煤电厂周边农田土壤重金属污染特征及源解析  

Characteristics and Source Analysis of Heavy Metal Pollution in Farmland Around a Coal-fired Power Plant

作　　者：张军[1,2] 李旭[1] 刘磊玉 李雨茹 ZHANG Jun;LI Xu;LIU Lei-yu;LI Yu-ru(Shannxi Key Laboratory of Disaster Monitoring and Mechanism Simulation,Baoji University of Arts and Sciences,Baoji 721013,China;Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education,Chang'an University,Xi'an 710064,China)

机构地区：[1]宝鸡文理学院陕西省灾害监测与机理模拟重点实验室,宝鸡721013 [2]长安大学旱区地下水文与生态效应教育部重点实验室,西安710064

出　　处：《环境科学》2023年第12期6921-6932,共12页Environmental Science

基　　金：国家自然科学基金项目(41771215);旱区地下水文与生态效应教育部重点实验室(长安大学)开放基金项目(300102290504);陕西省灾害监测与机理模拟重点实验室项目(20JS012)。

摘　　要：为探究某燃煤电厂污染物排放中重金属对周边农田土壤环境的影响,采用辐射环形法,以电厂烟囱为中心,布设31个农田土壤采样点.使用电感耦合等离子体质谱仪(ICP-MS)测定土壤中10种重金属含量,分析土壤中重金属含量特征及潜在生态风险,基于地统计空间插值和AERMOD扩散模型对重金属空间分异情况和污染特征进行探究,并运用PMF受体模型对重金属进行源解析.结果表明:(1)燃煤电厂周边农田土壤重金属ω(Pb)、ω(Mn)、ω(Zn)、ω(Cr)、ω(Ni)、ω(Cu)、ω(As)、ω(Co)、ω(Hg)和ω(Cd)的平均值分别为414.46、286.38、155.22、69.54、55.77、53.48、31.73、19.86、0.78和0.71 mg·kg-1,其中Hg、Pb、Cd、As、Zn、Cu、Co、Cr和Ni的含量均超过陕西省土壤背景值,分别为背景值的26、19.36、7.88、2.83、2.23、2.49、1.87、1.11和1.93倍,元素Cd、Cr、Ni和Zn的高值区出现在电厂西北方向.(2)燃煤电厂周边农田土壤重金属潜在生态风险指数(RI)的均值为714.53,整体处于很强的生态风险水平,并在千河火车站、石油天然气公司附近出现高值富集区,Hg元素的单项潜在生态风险指数(Ei)为520.92,处于极强的生态风险水平.(3)燃煤电厂周边农田土壤重金属主要来源为煤炭燃烧的降尘源(32.16%)、工农业活动源(19.78%)、自然源(26.25%)和交通源(21.81%).土壤重金属含量较高值均分布在距电厂1~2 km范围内,重金属含量在距离电厂1 km范围内较小,在1~2 km范围逐渐增大,大于2 km后又呈逐渐减小趋势.研究得出的电厂周边农田土壤重金属空间分异情况及富集特征,可为开展土壤污染治理提供理论及数据支撑.To explore the impact of heavy metals in pollutant emissions from a coal-fired power plant on the soil environment of surrounding farmland,31 farmland soil sampling sites were set up with the chimney of the power plant as the center using the radiation ring method.The contents of 10 heavy metals in the soil were determined using inductively coupled plasma mass spectrometry(ICP-MS).The characteristics and potential ecological risks of heavy metals in the soil were analyzed.The spatial differentiation and pollution characteristics of heavy metals were investigated based on geostatistical spatial interpolation and an AERMOD diffusion model,and the source analysis of heavy metals was conducted using a PMF receptor model.The results showed that:①the mean contents of the heavy metalsω(Pb),ω(Mn),ω(Zn),ω(Cr),ω(Ni),ω(Cu),ω(As),ω(Co),ω(Hg),andω(Cd)in farmland around coal-fired power plants were 414.46,286.38,155.22,69.54,55.77,53.48,31.73,19.86,0.78,and 0.71 mg·kg-1,respectively.The contents of Hg,Pb,Cd,As,Zn,and Cu all exceeded the background values of Shaanxi Province by 26,19.36,7.88,2.83,2.23,2.49,1.87,1.11,and 1.93 times,respectively.②The mean value of the potential ecological risk index(RI)of heavy metals in the soil around the coal-fired power plant was 714.53,indicating a strong ecological risk level,and there were high-value rich areas near the Qianhe railway station and the oil and gas company.The single potential ecological risk index(Ei)of the Hg element was 520.92,which was at a very strong ecological risk level.③The main sources of heavy metals in the soil around the coal-fired power plant were dust removal sources from coal burning(32.16%),industrial and agricultural activities(19.78%),natural sources(26.25%),and traffic sources(21.81%).The high heavy metal content in the soil was distributed in the range of 1-2 km from the power plant,whereas the heavy metal content was low in the range of 1 km from the power plant,increasing gradually in the range of 1-2 km and then decreasing gradually wh

关 键 词：燃煤电厂 土壤 重金属 生态风险 PMF模型 

分 类 号：X53[环境科学与工程—环境工程]