Characters of phosphorus sorption in sediment of Three Gorges Reservoir Xiangxi Bay

Abstract

Natural adsorption of phosphorus and the phosphorus force adsorption of different grain size on three samples of sediments taken form Xiangxi liver Bay Three Gorges Reservoir were determined in laboratory. The results indicated that the total phosphorus (TP) concentration of overlying water was significantly correlated to the TP concentration of sediment, the TP concentration of sediment influenced the water quality of the overlying water greatly. The critical equilibrium concentration of three samples were CI :0.188mg/L, C2:0.147mg/L and C3:0.188mg/L, respectively. And the saturated adsorption capacities were Delta Q1:268.16mg/kg, Delta Q2:57.96mg/kg, Delta Q3:267.27mg/kg; the two items were consistent. The influence of grain size oil phosphorus adsorption was significantly related to the physico-chemical properties of sediment. The adsorption capacities of three unfiltered samples were 1.5mg/g, 0.8mg/g and 1.4mg/g respectively. The result also indicated that the saturated adsorption capacities didn't change according to the largest adsorption capacities. The phosphorus in sediment of xiangxi liver was a source to overlying water until the environment condition changed. If the saturated adsorption capacities, largest adsorption capacities and critical equilibrium concentration can be correlated mathematically, the Department of the Enviroment will have a scientific basis to administer industries near the Xiangxi River