嵩明县上游水库沉积物重金属污染特征及生态风险评估  

Pollution Characteristics and Ecological Risk Assessment of Heavy Metals in the Sediments of Shangyou Reservoir in Songming County

作　　者：王燕萍 杨艳 邵智 段玲玲 孙晓能 李昕悦 熊健 WANG Yan-ping;YANG Yan;SHAO Zhi;DUAN Ling-ling;SUN Xiao-neng;LI Xin-yue;XIONG Jian(Kunming Research Academy of Eco-Environmental Sciences,Kunming Yunnan 650032,China)

机构地区：[1]昆明市生态环境科学研究院,云南昆明650032

出　　处：《环境科学导刊》2024年第3期83-88,共6页Environmental Science Survey

基　　金：长江生态环境保护修复城市(昆明市)驻点跟踪研究项目(NO.2022-LHYJ-02-0511-01)。

摘　　要：以嵩明县上游水库沉积物为研究对象,解析水库库尾、库中及闸坝不同区域沉积物8种重金属(Zn、Cu、Cr、Ni、Pb、As、Cd、Hg)的空间分布特征,并运用地累积指数法、潜在生态风险指数法、对重金属的污染特征和生态风险等级进行评估。结果表明:①Cu、Zn、Cr、Cd、Ni、Pb、Hg在上游水库沉积物中呈现不同程度的积累,平均含量分别是背景值的2.14、1.73、1.41、7.57、3.56、1.06、1.90倍,其中Cd的积累最为严重,主要来源于Cd的地球化学性质及农业活动,Hg、Zn、Cr、Ni具有相同来源的可能性较大,来源既有交通也存在工业;②从空间分布看,Cu、Zn、Cr、Ni、Pb、Hg含量分布为库尾>库中>闸坝,Cd为库中>闸坝>库尾,且Cd在库中和闸坝的含量明显高于库尾;③地累积指数表明,Cd是最主要的污染因子,上游水库沉积物中Cd处于中度-重度污染,Ni为中度污染,Cu、Hg、Zn为轻度-中度污染。从潜在生态风险指数来看,Cd在库中和闸坝表现为较强生态风险,在库尾为强生态风险,Hg在库尾为强生态风险,在库中和闸坝为中度生态风险,Cd对RI的贡献最大,达到65.16%,Hg次之,为22.42%。Taking the sediments of Shangyou reservoir of Songming County as the research object,the spatial distribution characteristics of eight heavy metals(Zn,Cu,Cr,Ni,Pb,As,Cd,Hg)in different areas of the reservoir tail,reservoir and lock dam were analyzed,and the pollution characteristics and ecological risk level of heavy metals were evaluated using the ground accumulation index method and potential ecological risk index method.The results showed that:Cu、Zn、Cr、Cd、Ni、Pband Hg indicated different degrees of accumulation in the reservoir sediments,and the average content were 2.14,1.73,1.41,7.57,3.56,1.06 and 1.90 times of the background value,respectively,among which the accumulation of Cd was the most serious,mainly from the geochemical properties of Cd and agricultural activities,and Hg,Zn,Cr and Ni were more likely to have the same source,and the sources were both from transportation and industry.From the spatial distribution,the content distribution of Cu,Zn,Cr,Ni,Pb and Hg was the reservoir tail>the reservoir>dam,Cd was the reservoir>lock dam>reservoir tail,and the content of Cd in the reservoir and lock dam was significantly higher than that in the reservoir and lock dam.The ground accumulation index showed that Cd was the most important pollution factor,and Cd was moderate-severely polluted in the sediments,Ni was moderately polluted,and Cu,Hg and Zn were mild-moderate pollution.From the perspective of potential ecological risk index,Cd showed strong ecological risk in reservoir and lock dam,strong ecological risk in reservoir tail,strong ecological risk in reservoir and dam,and moderate ecological risk in reservoir and lock dam,Cd contributed the most to RI,reaching 65.16%,followed by Hg with 22.42%.

关 键 词：上游水库 沉积物 重金属 污染程度 生态风险指数 

分 类 号：X82[环境科学与工程—环境工程]