千峡湖沉积物重金属含量空间分布及污染风险评价  

Spatial distribution and pollution risk assessment of heavy metal content in sediments of Qianxia Lake

作　　者：亢晓琪 刘倩[1,2] 罗明科 余辉[1,2] 兰伟 KANG Xiaoqi;LIU Qian;LUO Mingke;YU Hui;LAN Wei(Institute of Lake Environment,Chinese Research Academy of Environmental Science,Beijing 100012,China;National Engineering Laboratory for Lake Pollution Control and Ecological Restoration,Beijing 100012,China;College of Water Conservancy,Shenyang Agricultural University,Shenyang 110866,China)

机构地区：[1]中国环境科学研究院湖泊生态环境研究所,北京100012 [2]湖泊水污染治理与生态修复技术国家工程实验室,北京100012 [3]沈阳农业大学水利学院,辽宁沈阳110866

出　　处：《人民长江》2022年第7期50-56,共7页Yangtze River

基　　金：国家水体污染控制与治理科技重大专项(2018ZX07208-005)。

摘　　要：为探究千峡湖湖区表层沉积物重金属空间分布特征及污染风险程度,对湖区开展了现场调查及沉积物采样工作。采用相关分析法和主成分分析法对表层沉积物重金属来源进行解析,同时基于地累积指数法与潜在生态风险指数法对湖区污染情况及风险程度进行评价。结果表明:(1)湖区Cd超标严重,沉积物中Cd含量平均值为2.88 mg/kg,尤其在渤海镇(S6)、小粗口(S7),Cd含量超标倍数高达11.9和22.5倍。存在局部As偏高情况;(2)相关性分析和主成分分析结果表明,第1主成分为Cu、As、Pb,质量分数主要来源于农业生产过程中化肥农药大量施用和农村生活污水的输入,第2主成分为Cd、Zn,质量分数主要受农村生活及入湖河流影响,第3主成分为Cr,质量分数则来源于沉积物自身;(3)地累积指数和潜在生态风险指数结果表明,梅坑入湖(S5)、渤海镇(S6)及小粗口(S7)受沉积物重金属污染风险最高,其中重金属Cd污染风险水平较高。In order to reveal the spatial distribution and pollution risk of heavy metals in surface sediments of Qianxia Lake, field investigation and sediment sampling were carried out.Correlation analysis and principal component analysis(PCA)were employed to explore the sources of heavy metals in surface sediments.Meanwhile, the pollution situation and potential risk degree in the lake region were evaluated based on geo-accumulation index(I)and Hakanson potential ecological risk index(RI).The results indicated that:(1) Excessive Cd appeared in lake region seriously.The average Cd content in sediment was 2.88 mg/kg, especially at S6 and S7 point their exceeding times were 11.9 and 22.5 respectively.Phenomenon of local excess As existed.(2) The correlation analysis and principal component analysis showed that the Cu, As, Pb belonged to first principal components, which mainly derived from the large-scale use of fertilizers and pesticides during agricultural production and input of rural domestic sewage, and the content of Cd, Zn in the second principal components were primarily affected by rural living and inflowing rivers.The content of Cr in the third principal components were mainly influenced by the sediment itself.(3) The results of geo-accumulation index and potential ecological risk index suggested that the sediment pollution risks at S5,S6 and S7 were the highest, in which the Cd showed a severe potential ecological risk.

关 键 词：沉积物 重金属 空间分布 污染风险 千峡湖 

分 类 号：X524[环境科学与工程—环境工程]