贵州草海沉积物-水界面无机汞和甲基汞的扩散通量  

A Preliminary Study of the Diffuse Flux of Inorganic Mercury and Methylmercury at the Sediment-Water Interface of Lake Caohai,Guizhou Province

作　　者：钱晓莉[1,2] 冯新斌[1] 

机构地区：[1]中国科学院地球化学研究所环境地球化学国家重点实验室,贵阳550002 [2]贵州大学资源与环境工程学院,贵阳550003

出　　处：《西南大学学报（自然科学版）》2011年第3期104-108,共5页Journal of Southwest University(Natural Science Edition)

基　　金：国家自然科学基金重点资助项目(40532014);中国科学院知识创新工程重要方向资助项目(KZCX3-SW-443)

摘　　要：以贵州省草海湖泊沉积物孔隙水为研究对象,实测其溶解态甲基汞和溶解态无机汞的质量浓度,并根据质量浓度梯度和菲克第一定律,初步估算了沉积物-水界面溶解态无机汞和甲基汞的扩散通量.结果表明:不同季节沉积物孔隙水中无机汞、甲基汞与上覆水体中的无机汞、甲基汞之间均存在质量浓度梯度,其溶解态无机汞的质量浓度梯度在枯水期和丰水期分别为8.6 ng/L和25.1 ng/L;溶解态甲基汞的质量浓度梯度分别为0.46 ng/L和2.7 ng/L.在枯水期和丰水期沉积物孔隙水中无机汞的释放通量分别为31.4 ng/(m2.d)和52.8 ng/(m2.d);甲基汞的释放通量分别为1.7 ng/(m2.d)和3.9 ng/(m2.d).沉积物-水界面无机汞和甲基汞的扩散通量远低于同背景区的阿哈湖、红枫湖,并存在明显的季节性变化,其变化与孔隙水中汞的质量浓度的季节性变化一致,均为在丰水期的扩散通量大于在枯水期.In this study,seasonal distribution of dissolved inorganic mercury and methylmercury concentrations of the pore water was studied in Lake Caohai,and the diffuse flux of inorganic mercury and methylmercury at the sediment-water interface was estimated by concentration gradient and Fick,s first law.In the low flow period and the high flow period the concentration gradient of inorganic mercury was 8.6 ng/L and 25.1 ng/L and that of dissolved methylmercury was 0.46 ng/L and 2.7 ng/L,respectively;and the diffuse flux of inorganic mercury in the pore water was 31.4 ng/（m2·d） and 52.8 ng/（m2·d）,and that of methylmercury was 1.7 ng/（m2·d） and 3.9 ng/（m2·d）,respectively,being lower than in Lake Aha and Lake Hongfeng in the same background area.Obvious seasonal changes in the diffuse flux of the pore water were observed during the sampling periods,which was consistent with the variation in mercury concentration of the pore water.

关 键 词：无机汞 甲基汞 孔隙水 扩散通量 贵州草海 

分 类 号：X142[环境科学与工程—环境科学]