采集不同肥力的红壤上样５个，用超声波分散后沉降法分离出各级有机无机复合体，用平衡法作磷的吸附与解吸试验。结果表明：复合体对磷的吸附与解吸不仅与复合体的表面积大小有关，而且与土壤耕作熟化程度有关；土壤有机质能降低土壤及其复合体对磷的吸附量，增大对磷的解吸，提高土壤肥力。 Five red soil samples of different fertility were collected, and the organic-inorganic complexes at various levels were separated by ultrasonic dispersion and sedimentation method. The phosphorus adsorption and desorption experiments were performed by the equilibrium method. The results showed that the adsorption and desorption of phosphorus by the complex were not only related to the surface area of ​​the complex but also related to the tillage and maturity of the soil. The soil organic matter could reduce the amount of phosphorus adsorbed by the soil and its complex, increase the desorption of phosphorus, Improve soil fertility.