哈素海表层沉积物重金属时空分布特征、生态风险评价及来源解析  

Spatial and temporal distribution characteristics,ecological risk assessment and source analysis of heavy metals in surface sediments of Hasuhai Lake

作　　者：张贺玉 张静 卢少勇[1] 韩镇阳 石祖秦 张荣社 ZHANG He-yu;ZHANG Jing;LU Shao-yong;HAN Zhen-yang;SHI Zu-qin;ZHANG Rong-she(National Engineering Laboratory for Lake Pollution Control and Ecological Restoration,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Zhejiang Industry Polytechnic College,Shaoxing 312099,China)

机构地区：[1]中国环境科学研究院,湖泊水污染治理与生态修复技术国家工程实验室,北京100012 [2]浙江工业职业技术学院,浙江绍兴312099

出　　处：《中国环境科学》2025年第2期991-1003,共13页China Environmental Science

基　　金：国家重点研发计划项目(2021YFC3201505);科技基础性工作专项(2015FY110900)。

摘　　要：选取哈素海为研究对象,分别于2023年4月(枯水期)、2023年7月(丰水期)和2023年9月(平水期)各采集19个采样点的表层沉积物样品并测定了7种重金属(As、Cr、Cd、Cu、Pb、Zn和Hg)的含量(除Cr以外的重金属均检出),分析其污染及空间分布特征.采用地累积指数法(Igeo)和潜在生态风险指数法(RI)对6种重金属污染程度和潜在生态风险进行了评估,并结合相关性分析(CA)、主成分分析(PCA)和正定矩阵因子分解(PMF)模型解析了表层沉积物重金属的来源及相对贡献.结果表明,枯水期和丰水期6种重金属含量的平均值均超过内蒙水系沉积物背景值,平水期除As以外的5种重金属含量的平均值均超过内蒙水系沉积物背景值,其中Cd和Hg含量的平均值在3个水期均超过中国水系沉积物背景值;空间上,各水期表层沉积物重金属含量分布存在明显差异,枯水期重金属含量高值集中在湖区东西部,丰水期主要集中在湖区南北部,平水期则主要集中在湖区中部;地累积指数法结果和潜在生态风险指数法结果均表明Cd和Hg是造成3个水期生态风险的主要重金属元素,各水期RI均值分别为590.42、503.73和570.07,整体表现为强潜在生态风险水平,Cd和Hg在3个水期对RI值的贡献率之和均超过了90%;表层沉积物重金属的主要来源为农业生产活动和交通运输、工业活动、自然源和采矿活动,相对贡献率分别为32.5%、22.7%、20.1%和24.7%.Hasuhai Lake was selected as the research object,where surface sediment samples were collected from 19 sampling points during three water periods:April 2023(dry season),July 2023(wet season),and September 2023(normal season).The concentrations of seven heavy metals(As,Cr,Cd,Cu,Pb,Zn,and Hg)were determined,with all metals except Cr being detected.Subsequently,their pollution levels and spatial distribution characteristics were analyzed.The geo-accumulation index(Igeo)and potential ecological risk index(RI)were used to assess the potential ecological risks of six heavy metals,respectively.The correlation analysis(CA),principal component analysis(PCA)and positive matrix factorization(PMF)models were utilized to analyze the sources and relative contributions of heavy metals in surface sediments.The results indicated that the average contents of six heavy metals in both dry and wet season exceeded the background values of Inner Mongolia stream sediments,and the average contents of five heavy metals except As in normal season exceeded the background values of Inner Mongolia stream sediments.The average contents of Cd and Hg exceeded the background values of Chinese stream sediments in the three water periods.Spatially,the distribution of heavy metals content in surface sediments of each water period is significantly different.The high value of heavy metals content in the dry season is concentrated in the east and west of the lake area,the wet season is mainly concentrated in the north and south of the lake area,and the normal season is mainly concentrated in the middle of the lake area.The results of the geo-accumulation index method and the potential ecological risk index method revealed that Cd and Hg were the main heavy metals elements causing ecological risks in the three water periods,and the mean values of RI in each water period were 590.42,503.73 and 570.07 respectively,indicating a strong potential ecological risk.The sum of the contribution rates of Cd and Hg to RI values in the three water periods exceeded 9

关 键 词：表层沉积物 重金属 时空分布 潜在生态风险 来源解析 

分 类 号：X524[环境科学与工程—环境工程]