通过模拟试验研究了水稻根系泌氧作用对水稻土磷素化学行为以及水稻吸磷的影响。淹水极显著地增加土壤对磷的吸附 ,降低磷的解吸。而模拟的水稻泌氧作用则可明显降低土壤对磷的吸附 ,增加根际土壤的磷解吸和离子交换树脂对磷的吸收量。因此 ,水稻根系的泌氧作用应该是水稻在淹水明显降低土壤磷有效性情况下能正常从土壤获取磷的重要机制之一。淹水导致土壤磷有效性降低与淹水引起土壤磷组分转化有关。淹水 2周 ,经富磷预处理而增加的 Al- P组分 ,几乎全被转化为 Fe- P The effects of rice root oxygenation on the phosphorus chemical behavior and phosphorus uptake in paddy soil were studied through simulated experiments. Flooding significantly increased soil phosphorus adsorption, reducing the desorption of phosphorus. Simulated rice oxygenation can significantly reduce soil phosphorus adsorption, increase soil rhizosphere soil desorption and ion exchange resin phosphorus uptake. Therefore, the oxygenation effect in rice roots should be one of the important mechanisms that rice can normally get phosphorus from soil under the condition of flooding to reduce soil phosphorus availability significantly. The decrease of soil phosphorus availability due to flooding is related to the conversion of soil phosphorus components by flooding. After 2 weeks of flooding, Al-P components increased by phosphorus-rich pretreatment were almost completely converted into Fe-P