Study on the Phosphorus Immobility of the Re-suspended Sediments

The variation of EPC₀s of the re-suspended sediments is studied and the relationship between the distribution of phosphorus forms and EPC₀s of sediments is investigated. Results of this study show that sediment re-suspension could promote phosphorus migration from overlying water to the sediments. The EPC₀ of the re-suspended sediments reduced evidently from 0.069 mgldrL^-1 (the initial state) to 0.034 mgldrL^-1, whereas the values of the sediments without re-suspension increased slightly from 0.069 mgldrL^-1 (the initial state) to 0.071 mgldrL^-1 (the control experiment) and 0.073 mgldrL^-1 (aerating to water), respectively. The EPC₀s of the sediments had remarkable positive correlation with the concentrations of various phosphorus forms (BD-P+Al-P+NaOH-nrP) in those sediments except for the re-suspended sediments. It was suggested that the characteristics of BD-P, Al-P and NaOH-nrP formed under sediment re-suspension was different evidently from the initial state.