Abstract:A static adsorption and desorption experiment in couple with a simulated flooding experiment was carried out to study effect of combined application of polyacrylamide (PAM) and enhancers (lime, gypsum, natural zeolite and humus) on retention characteristics and translocation and release of soil P to water body in purple soil. Results of the adsorption/desorption experiment show that application of PAM coupled with any of the four enhancers enhanced soil P fixation capacity, with average P desorption volume and rate being lower than in CK. Of the four combinations, Treatment P0.2+L (PAM+lime) was the highest in P adsorption capacity, which was followed by Treatment P0.2+H (PAM+humus). In addition, Elovich and Two constant models could be used successfully to describe the sorption processes of all treatments except for PAM+gypsum (P0.2+G) and P0.2+H, which fitted the paraboloid diffusion equation Results of the flooding batch experiment show that monoapplication of PAM, regardless of rate (0.1%PAM(P0.1), 0.2%PAM(P0.2) and 04%PAM(P0.4)), reduced the strength of BAP release, and when combined with enhancers, PAM effectively inhibited release of BAP and reduced strength of the release, except for Treatment P0.2+H. The effect of Treatment P0.2+L was the best, keeping the mean BAP concentration and release strength at the lowest (0.267 mg L-1 and 1.852 mg m-2 d-1 respectively) in the overlaying water body. After alternation of wetting and drying, the effect of PAM mono-application, regardless of rate, decreased significantly, showing no much difference from CK. However combined application with chemical enhancer, except for Treatment P0.2+H, improved the effect of PAM inhibiting BAP release to water body.