基于DGT技术评估南四湖沉积物-水界面中Cr,Mo和W的潜在释放风险

本文利用DGT技术对南四湖污染程度不同的两个湖区(微山湖和独山湖)DGT有效态Cr,Mo和W的垂直分布特征以及沉积物-水界面元素的净扩散通量进行研究。结果表明微山湖区Cr,Mo,W的垂直分布趋势较为相似,呈现从上覆水向沉积物降低的趋势,据相关性分析得出三种元素都受铁锰氧化物的控制,三种元素的扩散通量分别为-14.31μg/m^2·day,-0.88μg/m^2·day和-0.38μg/m^2·day,表明微山湖三种元素向上覆水释放的风险较低。独山湖区三种元素的浓度均呈现从上覆水向沉积物增加的趋势,并在-12mm处出现峰值,三种元素的净扩散通量为5.36μg/m^2·day,-0.0025μg/m^2·day和0.37μg/m^2·day,这表明在独山湖Cr和W存在一定的向上覆水体释放的风险。

Evaluation of potential release risk of Cr,Mo and W in sediment-water interface of Nansi Lake based on DGT technology

The vertical distribution characteristics of available Cr,Mo and W and the net diffusion flux at the sediment-water interface in two lake areas(Weishan Lake and Dushan Lake)with different pollution levels in Nansi Lake were analyzed by DGT technology.The result indicated that the vertical distribution trends of Cr,Mo,and W in Weishan Lake are similar,decreased from overlying water to sediment.According to correlation analysis,all the three elements were controlled by iron and manganese oxides.The fluxes were-14.31μg/m^2·day,-0.88μg/m^2·day and-0.38μg/m^2·day respectively,indicated that the release risks of the three elements in Weishan Lake were lower.The concentration of the three elements in the Dushan Lake showed a tendency to increase from the overlying water to the sediment,and the peak value was in-12 mm.The net diffusion flux of the three elements were 5.36μg/m^2·day,-0.0025μg/m^2·day and 0.37μg/m^2·day,which indicated that the Cr and W in Dushan Lake might release from sediment to overlying water.