2003-2021年洞庭湖沉积物中重金属时空分布特征及生态风险评价  

Spatiotemporal Distribution Characteristics and Ecological Risk Assessment of Heavy Metals in Dongting Lake Sediments from 2003 to 2021

作　　者：刘霄 黄张根[1] 卢洪斌 LIU Xiao;HUANG Zhanggen;LU Hongbin(State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China;School of Architecture,Southwest Jiaotong University,Chengdu 611756,China)

机构地区：[1]中国科学院山西煤炭化学研究所,煤炭高效低碳利用全国重点实验室,太原030001 [2]西南交通大学建筑学院,成都611756

出　　处：《生态毒理学报》2025年第2期281-296,共16页Asian Journal of Ecotoxicology

基　　金：山西省区域合作项目(202304041101039);山西省基础研究计划项目(202203021222404);中国科学院山西煤炭化学研究所自主创新基金资助项目-基础研究项目(SCJC-WRW-2023-18)。

摘　　要：为深入了解洞庭湖重金属污染状况及其生态风险,本文收集了2003—2021年洞庭湖沉积物中7种典型重金属(Hg、As、Cd、Cr、Pb、Cu、Zn)数据,使用ANOVA检验、Daniel趋势检验等方法研究了重金属污染时空分布特征。利用地累积指数法(I_(geo))对数回归模型法(Y)、潜在生态风险指数法(RI)评价了洞庭湖及其子湖区重金属污染的生态风险,并探究了洞庭湖主要支流对重金属污染的贡献,同时结合流域土地分类数据追溯了重金属来源。结果表明,Cd为洞庭湖水环境重金属污染的首要因子,其含量范围为水系沉积物背景值的2.79倍~38.09倍,并且其年际平均值超过风险管制值(3.00 mg·kg^(-1))。Daniel趋势检验结果显示,近20年来,洞庭湖全湖的As、Pb、Cr、Cu、Zn均呈下降趋势(r<0);从区域上看,西洞庭湖的As、Pb,南洞庭湖的Pb和东洞庭湖的Hg、As、Cd、Pb、Cr、Cu、Zn呈下降趋势(r<0)。洞庭湖重金属污染的生态风险值2003—2017年呈上升趋势,之后下降,湖区生态风险排序为南洞庭湖>东洞庭湖>西洞庭湖,其中南洞庭湖Cd风险是3个湖区中最高的,贡献率达80.25%。重金属污染贡献最大的支流是湘江和资水,主要来源是工矿产业。因此,应该特别关注湘江、资水流域内的矿产采掘及金属冶炼的治理。To investigate the status and ecological risk of heavy metal pollution in Dongting Lake,data on seven typical heavy metals(Hg,As,Cd,Cr,Pb,Cu,Zn)in the lake’s sediments from 2003 to 2021 were collected.The spatial and temporal distribution of heavy metals was analyzed using ANOVA and the Daniel statistic test.Additionally,the ecological risk of heavy metal pollution in Dongting Lake and its sub-lakes was assessed using the geoaccumulation index(I_(geo)),logistic regression modeling(Y),and the potential ecological risk index(RI).The sources of pollution were traced by investigating the contributions of tributaries and the classification of land use.The results indicated that Cd is the primary water pollutant in Dongting Lake,with concentrations ranging from 2.79 to 38.09 times the sediment background mean value of the lake.During the study period,its average concentration exceeded the risk control value(3.00 mg·kg^(-1)).As,Pb,Cr,Cu,and Zn in Dongting Lake have shown a decreasing trend over the past 20 years.Furthermore,As and Pb in the West Dongting Lake,Pb in the South Dongting Lake,and Hg,As,Cd,Pb,Cr,Cu,and Zn in the East Dongting Lake have shown a decreasing trend.The ecological risk index of Dongting Lake increased from 2003 to 2017,then decreased thereafter.The ecological risk index decreased in the following order:South Dongting Lake,East Dongting Lake,and West Dongting Lake.The Cd value in South Dongting Lake was the highest among the three sub-lakes,accounting for 80.25%of the total contribution.The Xiangjiang River and Zishui River are the primary contributors to heavy metal pollution,mainly due to industrial and mining activities.Therefore,special attention should be focused on controlling mineral mining and metal smelting in the Xiangjiang River and Zishui River basins.

关 键 词：重金属 洞庭湖 生态风险 沉积物 时空分布 来源解析 

分 类 号：X171.5[环境科学与工程—环境科学]