焦作市采暖期降尘中重金属生态风险评价与源解析  

Ecological Risk Assessment and Source Analysis of Heavy Metals in Dust-fall in Jiaozuo City,China

作　　者：王明仕[1] 曹景丽[1] 李晗[1] 桂晨露 宋党育[1] WANG Mingshi;CAO Jingli;LI Han;GUI Chenlu;SONG Dangyu(School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454003, China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454003

出　　处：《生态环境学报》2017年第5期824-830,共7页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41272173);河南省高等学校重点科研项目(16A170001);河南省高校基本科研业务费专项(NSFRF1631)

摘　　要：随着工业经济的快速发展,降尘中重金属对环境的危害日趋严重,特别是在采暖期表现得尤为突出。焦作市是典型的燃煤城市,工业污染较为严重。为了解焦作市采暖期大气降尘量及其重金属的污染程度,在焦作市设置30个采样点,进行了降尘重金属的生态风险评价和源解析。结果表明:焦作市冬季降尘量平均值为20.51 t·km^(-2)·month^(-1),各种重金属元素质量分数在不同采样点的分布存在明显差异,其主要与降尘中重金属来源有关。降尘中重金属Cr、Co、Ni、Cu、As、Cd、Pb、Zn质量分数分别为68.90、9.58、40.22、68.07、35.47、8.11、157.15、1 809.58 mg·kg^(-1)。富集因子结果显示:Cd达到极强的富集程度;Zn和Pb呈显著富集;Cu和As为中度富集;Ni为轻微富集;Cr和Co的富集因子均小于1,说明其来自自然环境。潜在生态风险评价结果显示:Cd的潜在生态风险系数高达3 236.22,达到极强水平;As和Pb的最大潜在生态风险指数较高,达到中等水平;Cu和Zn的潜在生态风险指数最大值接近中等污染水平;其他重金属元素的潜在风险系数较小,生态危害程度不大。采用因子分析法对降尘中Cr、Co、Ni、Cu、As、Cd、Pb、Zn、Ca、Si、Al、Fe、K、Mg等14种元素进行源解析,提出4个主成分因子,分析结果表明:焦作市采暖期大气降尘主要来自于土壤尘,占24.89%;工业尘占19.33%;燃煤燃油尘占16.89%;道路扬尘占9.51%。With the rapid development of industrial economy,heavy metal pollution in dust fall becomes increasing serious,especially in heating period.Jiaozuo is a typical coal-burning city,coal-burning and industry production lead to heavy metal pollutionseriously.To investigate the pollution of heavy metals in Jiaozuo city,30sampling sites were set up.Based on concentration analysisof heavy metals in the dust,researches on ecological risk assessment and source apportionment were carried out.The average dustfall in Jiaozuo was20.51t?km-2?month-1,and the average mass concentration of Cr,Co,Ni,Cu,As,Cd,Pb,Zn was68.90,9.58,40.22,68.07,35.47,8.11,157.15,1809.58mg?kg-1,respectively.The enrichment factor showed that Cd reached extremelyenrichment;Zn and Pb elements showed significant enrichment;Cu and As was moderate enrichment;Ni is slightly enriched;enrichment factor of Cr and Co was less than1,which indicated it came from the natural environment.According to risk assessment,the following results had been obtained.The potential ecological risk coefficient of Cd was3236.22,reached a very high level.While As and Pb was at the medium level and followed by Cu and Zn,the potential risk factors of other heavy metal elements weresmall.On the whole,the ecological risk was not high.Results of factor analysis indicated that elements(Cr,Co,Ni,Cu,As,Cd,Pb,Zn,Ca,Si,Al,Fe,K,Mg)in the dust fall of Jiaozuo city mainly came from soil dust,industrial dust,fuel and coal dust,rode dustwith the contribution rates of24.89%,19.33%,16.89%and9.51%,respectively.

关 键 词：降尘 重金属 生态风险 源解析 

分 类 号：X51[环境科学与工程—环境工程]