千河下游水体-沉积物重金属空间分布、风险及影响因素  

Spatial Distribution,Risk,and Influencing Factors of River Water-Sediment Heavy Metals in the Lower Reaches of the Qianhe River

作　　者：高煜 王国兰 金梓函 张军[1,2] 耿雅妮[1] GAO Yu;WANG Guo-lan;JIN Zi-han;ZHANG Jun;GENG Ya-ni(Shaanxi Key Laboratory of Disaster Monitoring and Mechanism Simulation,Baoji University of Arts and Sciences,Baoji 721013,China;Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education,Chang'an University,Xi'an 710064,China)

机构地区：[1]宝鸡文理学院陕西省灾害监测与机理模拟重点实验室,宝鸡721013 [2]长安大学旱区地下水文与生态效应教育部重点实验室,西安710064

出　　处：《环境科学》2021年第11期5333-5345,共13页Environmental Science

基　　金：国家自然科学基金项目(41771215);旱区地下水文与生态效应教育部重点实验室(长安大学)开放基金项目(300102290504);陕西省社科界重大理论与现实问题研究项目(2020Z042);陕西省灾害监测与机理模拟重点实验室项目(20JS010)。

摘　　要：为了研究千河下游水体-沉积物重金属污染特征、风险程度及其影响因素,采集千河下游表层沉积物19份及水样20份,使用电感耦合等离子体质谱仪(ICP-MS)测定8种重金属(As、Cd、Cr、Cu、Mn、Ni、Pb和Zn)含量,分析了水体中重金属含量和健康风险,对沉积物重金属空间分布及污染特征进行探析,以DEM、气温和降水等11种因子为自变量,结合地理探测器和地理加权回归模型对沉积物重金属污染影响因素进行空间分异探究.结果表明,千河下游8种水体重金属浓度均未超过地表水环境质量标准Ⅱ类水体标准,其中Pb元素变异系数为3.11,浓度高值区主要集中于东岭冶炼公司和凤翔火车站周围.水体成人致癌物Rc均值为7.72E-06,呈较轻风险程度,儿童致癌物Rc均值为1.17E-04,呈强风险程度,成人与儿童非致癌物风险均为可承受风险程度,儿童R总的高值主要集中在凤翔火车站周边,呈较强风险程度;千河下游沉积物重金属除As和Mn外,其余6种元素均超过陕西省土壤背景值,其中Cd元素含量均值为1.12 mg·kg^(-1),是陕西省土壤背景值的12倍,Cd、Zn和Pb污染较严重,主要分布在长青村、南湾村地区、牛家滩村、高庄和东岭冶炼公司周围;研究区沉积物重金属PLI_(zone)为1.71,属于轻度污染;DEM、温度和降水是沉积物重金属PLI空间格局的主要自然影响因素,其交互作用均为非线性增强,对沉积物重金属空间污染扩散起到一定驱动作用.The spatial distribution of heavy metals in rivers is affected by human activities and the natural environment,posing a risk to human health related to heavy metal pollution.In order to study the characteristics,health risk levels,and influencing factors of heavy metal distribution and pollution in the lower reaches of the Qianhe River,19 surface sediments and 20 water samples were collected,and the contents of As,Cd,Cr,Cu,Mn,Ni,Pb,and Zn were measured by inductively coupled plasma mass spectrometry(ICP-MS).Using the DEM,air temperature,precipitation and other 11 factors as independent variables,the spatial differentiation of heavy metal pollution in sediments were explored based on geo-detector and geo-weighted regression model.The results showed that the eight heavy metal contents in the lower reaches of the Qianhe River did not exceed the“Surface Water Environmental Quality Standards”Ⅱfor water-like bodies,in which the variation coefficient of Pb element was 3.11,and the high content areas were mainly concentrated around Dongling Smelting Company and Fengxiang Railway Station.The average Rc value of adult carcinogens in water bodies was 7.72 E-06,showing a low risk level,and the children's carcinogens average Rc value was 1.17 E-04,showing a strong risk degree.The non-carcinogen risks for adults and children were both tolerable.The total high R value for children was mainly concentrated around Fengxiang Railway Station,posing a high risk.Sedimentation of heavy metals,except As and Mn,exceeded the soil background value in Shaanxi Province.The average content of Cd element was 1.12 mg·kg^(-1),which was 12 times the soil background value in Shaanxi Province.The pollution of Cd,Zn,and Pb was high,and distributed mainly in Changqing Village,Nanwan Village and Niujiatan Village,Gaozhuang,and Dongling Smelting Company.PLI_(zone) of heavy metals in the sediments in the study area was 1.71,which was light pollution.DEM,temperature and precipitation were the main natural factors influencing the spatial pattern of

关 键 词：重金属 空间分布 风险评价 地理探测器 地理加权回归(GWR) 千河 

分 类 号：X52[环境科学与工程—环境工程]