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)

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.