中国重点潮间带沉积柱砷和汞的环境本底值构建及污染评价  

Construction of Background Values of Arsenic and Mercury and Their Pollution Assessment in Key Intertidal Sediment Cores of China

作　　者：蔡壮 侯国华[2,3] 高茂生 CAI Zhuang;HOU Guohua;GAO Maosheng(College of Marine Science and Technology,China University of Geosciences(Wuhan),Wuhan 430000,China;Qingdao Institute of Marine Geology,China Geological Survey,Qingdao 266000,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266000,China)

机构地区：[1]中国地质大学(武汉)海洋学院,湖北武汉430000 [2]中国地质调查局青岛海洋地质研究所,山东青岛266000 [3]青岛海洋科学与技术试点国家实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266000

出　　处：《岩矿测试》2022年第5期857-866,共10页Rock and Mineral Analysis

基　　金：国家自然科学基金项目(U2106203,42076070);科技部工作基础性专项(2014FY210600);地下水循环与环境演化教育部重点实验室开放课题基金(2020-002);山东省自然科学基金青年项目(ZR2021QD011)。

摘　　要：潮间带沉积物中砷、汞污染会导致该区域的动植物中砷、汞含量超标,严重影响当地植被的生态环境,进一步影响人类的生存安全,因此研究潮间带沉积物中砷、汞含量变化和空间分布具有重要的现实意义。本文选择大辽河口、苏北盐城浅滩、闽江口和珠江口4个潮间带为研究区,对沉积物砷、汞元素含量进行调查与对比研究,为潮间带沉积物砷、汞污染情况提供基础资料。利用原子荧光光谱法测定了研究区沉积物中砷、汞元素含量,选取铁元素作为归一化元素,建立了不同潮间带沉积物砷、汞元素的环境背景值。统计结果表明:砷、汞含量最大值均出现珠江口,分别为42.90mg/kg和0.287mg/kg,大于第一类《海洋沉积物质量标准》中砷的20.0mg/kg标准值和汞的0.2mg/kg标准值。本文采用地质累积指数法和潜在生态危害指数法对研究区砷、汞污染状况进行评价。在砷含量背景值中:珠江口最大值为19.19mg/kg,苏北盐城浅滩为11.02 mg/kg,大辽河口为6.42mg/kg,闽江口最小值为2.90mg/kg;在汞含量背景值中:珠江口最大值为0.08mg/kg,其余三个河口均较小,大辽河口为0.03mg/kg,盐城浅滩为0.02mg/kg,闽江口为0.02mg/kg;砷、汞元素本底值最大值均出现在珠江口,最小值位于闽江口;砷元素在4个潮间带沉积物中均属于无污染情况和轻微的潜在生态危害,汞元素在珠江口为中等潜在生态危害,在其他3个潮间带沉积物中为轻微污染或者无污染情况。研究区中4个潮间带沉积物中砷、汞含量呈“南方高,北方低”的分布特征。闽江口和珠江口潮间带沉积物中砷、汞元素含量受人类工农业活动影响较大,因此造成了砷、汞含量呈现“南高北低”的分布特征,且珠江口的砷、汞污染情况较其他潮间带更为严重,亟需加强控制其污染趋势。BACKGROUND:The contamination of arsenic and mercury in intertidal sediments will lead to excessive levels of arsenic and mercury in the flora and fauna of the region,which will seriously affect the ecological environment of local vegetation and further affect the survival and safety of human beings.Therefore,it is of great practical significance to study the changes in the contents and spatial distribution of arsenic and mercury in intertidal sediments.OBJECTIVES:To investigate the contents of arsenic and mercury in sediments,so as to provide basic information on the pollution of arsenic and mercury in intertidal sediments.METHODS:The contents of arsenic and mercury in the sediments of the study area were determined by atomic fluorescence spectrometry(AFS),and iron was selected as the normalized element to establish the environmental background values of arsenic and mercury elements in different intertidal sediments.The geoaccumulation index method and potential ecological hazard index method were used to evaluate the pollution status of arsenic and mercury in the study area.RESULTS:Background value of arsenic content:Minjiang Estuary(2.90mg/kg)<Daliao Estuary(6.42mg/kg)<Yancheng Shoal in northern Jiangsu(11.02mg/kg)<Pearl River Estuary(19.19mg/kg).Background value of mercury content:maximum in Pearl River Estuary(0.08mg/kg),less in Daliao Estuary,Yancheng shoal and Minjiang Estuary(0.02mg/kg,0.02mg/kg,0.03mg/kg,respectively).The maximum values of background values of arsenic and mercury were both found in the Pearl River Estuary,and the minimum values were located in the Minjiang Estuary.The maximum values of arsenic and mercury of sediments were both found in the Pearl River Estuary,which were 42.90mg/kg and 0.287mg/kg,respectively,and were greater than the first class of Marine Sediment Quality Standard(arsenic:20.0mg/kg;mercury:0.2mg/kg).Arsenic belonged to no pollution and slight potential ecological hazards in the four intertidal sediments.Mercury was a medium potential ecological hazard in the Pearl River

关 键 词：潮间带 沉积物 重金属 背景值 污染评价 原子荧光光谱法 

分 类 号：X820.4[环境科学与工程—环境工程] P66[天文地球—地质学]