太湖不同富营养化水域砷的分布特征及其环境影响因素  

Distributions of Arsenic Species in Different Eutrophic Waters of Lake Taihu and Their Relations to Environmental Factors

作　　者：车霏霏[1,2] 王大鹏[1,2] 甄卓[1] 颜昌宙[1] 王灶生[1] 

机构地区：[1]中国科学院城市环境研究所,城市环境与健康重点实验室,厦门361021 [2]中国科学院大学,北京100049

出　　处：《环境科学》2016年第9期3340-3347,共8页Environmental Science

基　　金：国家自然科学基金项目(21277136);国际科技合作与交流专项(2011DFB91710)

摘　　要：对夏季与冬季太湖不同营养水平湖区(竺山湾、梅梁湾、贡湖湾和南太湖)上覆水的砷含量及水质参数进行调查,运用多元分析技术分析砷的空间与季节分布特征及其与水质参数之间的关系.结果表明,北部湖区(竺山湾、梅梁湾和贡湖湾)水体中总砷(TAs)、砷酸盐[As(Ⅴ)]、亚砷酸盐[As(Ⅲ)]及甲基砷(MMA+DMA)的平均含量(2.58~3.34、1.37~2.34、0.53~0.64和0.16~0.36μg·L-1)均高于南太湖(1.73、1.10、0.31和0.10μg·L-1),显示了砷在太湖北部与南部的空间分布差异.此外,夏季TAs、As(Ⅴ)、As(Ⅲ)和甲基砷的平均含量分别为3.40、2.06、0.73和0.25μg·L^(-1),均高于冬季(1.78、1.10、0.30和0.17μg·L^(-1)),呈现明显的季节分布特征.因子分析与冗余分析结果进一步表明,总磷(TP)、总铁(TFe)和叶绿素a(Chl-a)是影响太湖水体砷时空分布的关键环境因子.其中,TP、TFe与太湖水体中TAs和As(Ⅴ)的分布存在显著正相关;Chl-a含量对As(Ⅲ)和甲基砷的分布有显著影响,推测浮游植物(Chl-a)对砷还原和生物甲基化具有一定的调控作用.A detailed field survey of arsenic species and water quality parameters was conducted in different eutrophicated regions of Lake Taihu（ Zhushan Bay,Meiliang Bay,Gonghu Bay and Southern Taihu） in summer and winter. Furthermore,spatial and seasonal distributions of arsenic species and their relations to water quality parameters were investigated with multivariate analysis techniques.Higher average contents of total arsenic（ TAs）, arsenate [As（ Ⅴ） ], arsenite [ As（ Ⅲ） ] and methylarsenicals [sum of monomethylarsenic acid（ MMA） and dimethylarsenic acid（ DMA） ] were observed in northern regions（ including Zhushan Bay,Meiliang Bay,and Gonghu Bay）（ TAs： 2. 58-3. 34 μg·L^-1,As（ Ⅴ） ： 1. 37-2. 34 μg·L^-1,As（ Ⅲ） ： 0. 53-0. 64 μg·L^-1,methylarsenicals： 0. 16-0. 36 μg·L^-1）,compared to those in Southern Taihu（ 1. 73,1. 10,0. 31,0. 10 μg·L^-1）. The results exhibited obvious spatial characteristics of arsenic species in the surface water of Lake Taihu. Besides,average values of TAs,As（ Ⅴ）,As（ Ⅲ） and methylarsenicals in summer were 3. 40,2. 06,0. 73 and 0. 25 μg·L^-1,respectively,higher than those in winter（ 1. 78,1. 10,0. 30,0. 17 μg·L^-1）,reflecting significant seasonal characteristics of arsenic distribution. Factor analysis revealed the significant relationships of TAs and As（ Ⅴ） with several water quality parameters,which suggested that spatial and seasonal distributions of TAs and As（ Ⅴ） in Lake Taihu were affected by external pollution and internal arsenic release from sediments.Redundancy analysis further indicated significant effects of total phosphorus（ TP） and total iron（ TFe） on the distributions of TAs and As（ Ⅴ）. At the mean time,the above statistical analyses exhibited that As（ Ⅲ） and methylarsenicals were positively correlated with chlorophyll-a（ Chl-a）. A large amount of microalgae could accumulate As（ Ⅴ） and transform it more strongly to As（ Ⅲ） and methylarsenicals in eutroph

关 键 词：砷形态 水质参数 砷转化 富营养化 太湖 

分 类 号：X524[环境科学与工程—环境工程]