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采用连续液流法研究了黄土性土壤吸附、解吸磷酸根的动力学性质。结果表明：（１）供试土壤对磷酸根的吸附、解吸按速率可分为快、中、慢三种反应类型；（２）描述吸附、解吸反应的最优模型均为Ｅｌｏｖｉｃｈ方程，最差模型分别为一级反应方程及双常数方程，拟合差的模型对反应速率变化“敏感”，可用于反应类型划分和机理研究；（３）粘粒含量及代换量对吸附速率有显著影响，游离铁对吸附速率、ＣａＣＯ＿３对较低温度下的吸附及较高温度下的解吸速率也有明显影响，速效磷含量是控制解吸速率的重要因子；（４）升高温度吸附加速，但对解吸速率无明显影响；（５）不同土类及同一剖面不同层次的吸附、解吸速率，反应时间及吸附、解吸量不同。
The kinetic properties of phosphate adsorption and desorption in loess soil were studied by continuous flow method. The results showed that: (1) The adsorption and desorption of phosphate by the soil tested can be divided into three types: fast, medium and slow. (2) The optimal models describing the adsorption and desorption reactions are the Elovich equation, the worst The models are the first-order reaction equation and the bivariate equation, respectively. The fitting difference model is “sensitive” to the change of reaction rate and can be used for the classification and mechanism of reaction types. (3) The clay content and displacement have a significant effect on the adsorption rate , Free iron adsorption rate, CaCO_3 adsorption at lower temperature and higher temperature desorption rate also has a significant impact, available phosphorus content is an important factor controlling the desorption rate; (4) elevated temperature adsorption acceleration, but the desorption (5) The adsorption, desorption rate, reaction time, adsorption and desorption amounts of different soil layers and different layers of the same section are different.