Effects of flooding on iron transformation and phosphorus adsorption desorption properties in different layers of the paddy soils

A soil column simulated experiment was carried out to estimate the effect of flooding on iron transformation and phosphorus adsorption desorption properties in different layers of the paddy soils The results showed that the content of amorphous Fe oxides of the soils increased significantly with the decreasing of crystalline Fe oxides content during the flooding process, and the maximum capacity of P adsorption increased remarkably, while desorbed P/adsorbed P ratio decreased More notable changes of Fe forms and phosphorus adsorption and desorption properties were observed in the reduced layer of Ultisol, compared with those in the oxidized layer But there was no significant difference between the two layers in Entisol