半咸水宁夏沙湖沉积物中重金属的分布特征、潜在生态风险及来源解析  

Distribution characteristics,potential ecological risk and source analysis of heavy metals in the sediments of the brackish-water lake Ningxia Sand Lake

作　　者：王燕[1,2] 刘彦斌 赵红雪 连总强[2,3] 肖伟 赛清云 孙斌斌 张天旭 张锋 WANG Yan;LIU Yanbin;ZHAO Hongxue;LIAN Zongqiang;XIAO Wei;SAI Qingyun;SUN Binbin;ZHANG Tianxu;ZHANG Feng(School of Agriculture,Ningxia University,Yinchuan,750021,China;Ningxia Fishery Institute,Yinchuan,750001,China;Ningxia Fisheries Engineering Technology Research Center,Yinchuan,750001,China;Ningxia Fisheries Engineering Technology Research Center School of Life Science,Ningxia University,YInchuan,750021,China;Hebei University of Technology,school of Energy and Environmental Engineering,Tianjin,300401,China;Tianjin Key Laboratory of Remediation and Pollution Control for Urban Ecological Environment,Key Laboratory of Pollution Processes and Environmental Criteria,Ministry of Education,College of Environmental Science and Engineering,Nankai University,Tianjin,300350,China)

机构地区：[1]宁夏大学农学院,银川750021 [2]宁夏回族自治区水产研究所,银川750001 [3]宁夏渔业工程技术研究中心,银川750001 [4]宁夏大学生命科学学院,银川750021 [5]河北工业大学,能源与环境工程学院,天津300401 [6]南开大学环境科学与工程学院,环境污染过程与基准教育部重点实验室,天津城市生态环境修复与污染防治重点实验室,天津300350

出　　处：《环境化学》2023年第10期3287-3300,共14页Environmental Chemistry

基　　金：国家自然科学基金(42207435);宁夏回族自治区东西部合作项目-沙湖水环境质量改善与水生态功能提升技术研究与示范(2017BY087);国家大宗淡水鱼产业技术体系银川综合试验站项目(CARS-46-54);中国博士后科学基金(2020M680868);中央高校基本科研业务经费(5320116);天津市自然科学基金(20JCQNJC02120)资助。

摘　　要：为揭示和明确半咸水湖泊湿地的重金属污染状况,以宁夏沙湖为例,于2018年4月(春)、7月(夏)、10月(秋)、2019年1月(冬),对沙湖湿地9个采样点沉积物中有机质(OM)、总氮(TN)、总磷(TP)、硝态氮(NO_(3)^(−)-N)、全盐和6种对环境影响较大的有毒有害重金属(As、Pb、Hg、Cd、Cr、Cu)的含量进行了定量分析并运用多种手段进行风险评估.结果表明,人类活动密集区(湖心、鸟岛和2号桥)沉积物中OM和营养盐含量高于其他区域.全盐含量在夏季最高,冬季最低;OM、TN和TP含量在夏季最高,春季最低;NO_(3)^(−)-N含量在秋季含量最高,冬季最低.宁夏沙湖沉积物中As、Pb、Hg、Cd、Cr、Cu含量分别在8.83—13.55 mg·kg^(−1),16.61—21.71 mg·kg^(−1),0.02—0.08 mg·kg^(−1),0.02—0.46 mg·kg^(−1),51.16—66.54 mg·kg^(−1),14.67—24.42 mg·kg^(−1)之间,其中Pb和Cd含量均超过背景值.6种重金属单因子污染指数均小于1,地累积指数(Igeo)均小于0,表明宁夏沙湖沉积物质量状况良好,其中Cr、As和Pb单因子污染指数和Igeo指数较大,空间分布为假日酒店、湖心相对较高,需在今后监测工作中重点关注.潜在重金属生态风险为中等污染,仅Hg和Cd出现强和中等的生态危害程度,表明宁夏沙湖沉积物重金属生态风险主要由Hg和Cd造成,生态风险较高的区域主要位于假日酒店、湖心等区域.相关性分析和主成分分析揭示Pb、Cd、Cr、Cu、OM、TN、TP具有相似的污染来源,主要来源是人为来源和自然来源.本研究将为半咸水湖泊重金属污染状况及潜在生态风险提供数据支撑,也将为水环境污染防控提供科学依据.To reveal and clarify the heavy metal pollution status of brackish-water lake wetlands,we measured and analyzed the organic matter(OM),total nitrogen(TN),total phosphorus(TP),nitrate nitrogen(NO_(3)^(−)-N),total salt,and six types of environmentally relevant toxic and harmful heavy metals(As,Pb,Hg,Cd,Cr,Cu)from 9 sampling sites in April(spring),July(summer),and October(autumn)and January(winter)2018.The results showed that content of OM and nutrient salts in sediments were larger in locations with substantial human activity(Lake Center,Bird Island,and Bridge#2)than that of other regions,revealing that human activities impacted the spatial distribution of nutritional salts.Summer had the highest levels of total salt,whereas winter had the lowest levels.The OM,TN,and TP levels were highest in summer but lowest in spring,whereas the NO_(3)^(−)-N values were highest in fall but lowest in winter.As,Pb,Hg,Cd,Cr and Cu in the sediments of Ningxia Sand Lake ranged from 8.83—13.55 mg·kg^(−1),16.61—21.71 mg·kg^(−1),0.02—0.08 mg·kg^(−1),0.02—0.46 mg·kg^(−1),51.16—66.54 mg·kg^(−1),14.67—24.42 mg·kg^(−1),among which Pb and Cd were above the background values.The single-factor pollution index of six heavy metals was all less than 1,and the ground accumulation(Igeo)index of six heavy metals was all less than 0,suggesting that the sediment quality was satisfactory.While the single-factor pollution index and Igeo index of Cr,As,and Pb were higher,and the geographical distribution was quite high for Holiday Inn,Lake Center,which required further attention in monitoring work.The potential ecological risk of heavy metals in the sediments of the study area was all medium,whereas some Hg and Cd sites showed strong and medium ecological risk.These results indicated that the ecological risk of heavy metals in sediments of Sand Lake was mainly caused by Hg and Cd,and the high ecological risk areas are mainly located in Holiday Inn,Lake Center.Correlation analysis and principal component analysis revealed

关 键 词：宁夏沙湖 沉积物 营养盐 重金属 风险评价 

分 类 号：X524[环境科学与工程—环境工程] X820.4