巢湖沉积物有效态磷与硫的DGT原位同步分析研究

A study of in situ synchronous measurement of available phosphorus and sulfur in the sediments of lake Chaohu by diffusive gradients in thin films( DGT)

沉积物有效态磷(P)与硫(S)的含量分布是影响湖泊营养元素循环和水体富营养化的重要因子.本文利用Zr O-Ag I薄膜梯度扩散技术(Zr O-Ag I DGT)原位同步获取了南淝河-巢湖沉积物中有效态P和S的高分辨分布信息.结果发现:绝大部分沉积物有效P和S自界面向下呈急剧升高趋势,并在50 mm深度内出现峰值;河道内沉积物有效P和S的含量高于湖体,且P在界面的表观释放通量明显高于湖体,表明河道沉积物是湖体P的输入源.部分采样点出现有效P与S同步变化的现象,两者具有显著相关性,证实沉积物内部P和S存在同步释放的规律.

The content distribution of available phosphorus（ P） and sulfur（ S） in the sediment is an important factor for nutrient cycle and eutrophication in water. We obtained the in situ high resolution information of the distribution of available P and S simultaneously in lake Chaohu-river Nanfeihe by using Zr O-Ag I diffusive gradients in thin films（ Zr O-Ag I DGT）. The results show that the concentrations of available P and S have an obvious rising from the surface of sediment downwards,and appear peaks within 50 mm depth. There is a higher available P and S concentration in river than in lake,and the exchange flux of P at the interface is obviously higher than that in the lake,indicating that river sediment is the input source of P. There is a synchronous change of available P and S in some sampling points with a significant correlation,which confirms both elements have a synchronous release in the sediment.