珠江口伶仃洋水体及表层沉积物砷污染时空变化  

Temporal and spatial change of Arsenic pollution in water and surface sediments of Lingding Bay,Pearl River Estuary

作　　者：付淑清 钟霆堃 杨龙 谢露华[3] 唐光良[1] 宗永强 FU Shuqing;ZHONG Tingkun;YANG Long;XIE Luhua;TANG Guangliang;ZONG Yongqiang(Key Lab of Guangdong for Utilization of Remote Sensing and Geographical Information System,Guangdong Open Laboratory of Geospatial Information Technology and Application,Guangzhou Institute of Geography,Guangdong Academy of Sciences,Guangzhou,510070,China;Research Institute No.280,China National Nuclear Corporation,Guanghan,618300,China;State Key Laboratory of Isotope Geochemistry,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou,510640,China;Department of Earth Science,the University of Hong Kong,Hong Kong,999077,China)

机构地区：[1]广东省科学院广州地理研究所广东省遥感与地理信息系统应用实验室/广东省地理空间信息技术与应用公共实验室,广州510070 [2]核工业二八〇研究所,广汉618300 [3]中国科学院广州地球化学研究所同位素地球化学国家重点实验室,广州510640 [4]香港大学地球科学系,中国香港999077

出　　处：《环境化学》2023年第10期3341-3350,共10页Environmental Chemistry

基　　金：广东省科学院项目(2020GDASYL-20200401001,2023GDASZH-2023010104);广州市科技计划项目(201707010417);广东省科技计划项目(2021B1212100006)资助。

摘　　要：为了解珠江口伶仃洋砷污染状况,分别于2010年12月和2020年12月在该海域布点取样,样点布设位置和数量基本一致.2010年仅采集了表层沉积物样品,2020年采集了表层沉积物和水体样品,分别使用原子荧光法和ICP-MS法测试了水体和沉积物砷含量.结果显示,2020年时伶仃洋水体中溶解态的砷含量在2μg·L^(−1)左右,空间差异性小,与1976年以来的其他调查结果相近,指示该海域的水体砷含量在近40余年间未发生明显变化.2020年时表层沉积物砷平均含量为52.98 mg·kg^(−1),较2010年时(平均25.40 mg·kg^(−1))增加了1倍;空间分布上,由2010年时总体上从口门水道向外海方向递减的特征变为了2020年时的由近岸向远岸方向递增的特点.综合分析认为,近10年间,除来自陆域的砷输入总量依然较大之外,持续加剧的海上人类活动可能向水中排放了更多的含砷污染物,加上人类活动的强烈扰动及水环境变化(如持续富营养化)导致的底泥中的砷释放和再沉淀作用等,共同导致了砷在沉积物表层的进一步富集和在空间上的重新分配.总之,珠江口伶仃洋区域砷污染的潜在风险依然较为严峻,后期仍需加强监测和修复等相关工作.In December 2010 and December 2020,samples were taken in the Lingding Bay of the Pearl River Estuary to investigate its arsenic pollution change.These samplings were of nearly the same locations and quantities.Only surface sediment samples were collected in 2010,while surface sediment and water samples were collected in 2020.The arsenic contents of the water samples and all sediment samples were measured by using atomic fluorescence spectrometry(AFS)and ICP-MS,respectively.The results showed that the dissolved arsenic content in the water of Lingding Bay was about 2μg·L^(−1) with no significant deference in geographical distribution,which was similar to previous results since 1976,indicating that the arsenic content in the water of this sea area has not changed significantly during the past 40 years.The mean arsenic content of surface sediment was 52.98 mg·kg^(−1) in 2020,which is twice as that in 2010(25.40 mg·kg^(−1) on average).In 2010,the arsenic content of surface sediment decreased gradually from the watercourses to the open sea,while the spatial distribution characteristics of sediments arsenic content in 2020 was almost opposite to that in 2010.After a comprehensive analysis,it was believed that the main reasons for these changes in arsenic content of surface sediment during the past 10 years were as follows:1)The total amount of arsenic input from land areas was still large,2)increased human activities on the water input more arsenic containing pollutants into the water,3)The intense disturbance of human activities and changes of water environment had led to the release and transfer of arsenic in the sediment to the surface.In general,the potential risk of arsenic pollution in the Lingding Bay of the Pearl River Estuary was still severe.Further monitoring and remediation work should be enhanced in the later stage.

关 键 词：伶仃洋 水体 沉积物 砷污染 时空变化 

分 类 号：X55[环境科学与工程—环境工程]