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用(32)P标记扩散池法测定了不同时间下土壤磷的扩散量，并用5种动力学模型对其拟合，结果表明土壤磷扩散过程最符合抛物线扩散方程。20％含水量下，磷扩散速率温度商Q(10)。为1．20左右，与扩散是一个物理过程相吻合。由阿尼乌斯公式求得的磷扩散活化能（E）随土壤水分增加而降低；在土壤水低吸力范围内（＜105Pa水吸力）为12—34kJ／mol，平均为25kJ／mol左右，与溶液中离子扩散活化能较接近，说明低吸力下磷扩散主要在液相进行。将绝对反应速率理论移植用于磷扩散，所求出的磷扩散净活化能、活化熵变、活化焓变和活化自由能变在供试土壤中相同含水量下均呈规律性变化，且与E变化趋势基本一致，证明这些参数可用于表征磷扩散的能量特征。
The (32) P-labeled diffusion cell method was used to determine the amount of soil phosphorus diffusion at different times and fitted with five kinetic models. The results showed that the phosphorus diffusion process was the most consistent with the parabolic diffusion equation. Under 20% water content, the phosphorus diffusion rate temperature quotient Q (10). 1.20 or so, and proliferation is a physical process. The activation energy of phosphorus diffusion (E) obtained by Anius equation decreases with the increase of soil moisture. In the range of soil water suction (<105Pa water suction) is 12-34 kJ / mol with an average of about 25 kJ / mol, And the activation energy of ion diffusion in solution is closer, indicating that phosphorus diffusion is mainly carried out in liquid phase under low suction. The theory of absolute reaction rate was used for phosphorus diffusion. The calculated net activation energy of phosphorus diffusion, activation entropy change, activation enthalpy change and activation free energy change all showed regular changes under the same water content in the test soil, The trend of E is basically the same, proving that these parameters can be used to characterize the energy characteristics of phosphorus diffusion.