土壤磷运移研究

STUDIES ON PHOSPHORUS TRANSPORT IN SOILS

应用同位素３２Ｐ示踪法，对陕西省四种主要土壤（黄绵土、黑垆土、土、黄褐土）三种处理状态下的研究得出：（１）磷素很难“穿透”土柱，阻滞因子Ｒ均大于１；富含粘粒和碳酸钙的土壤，去除ＣａＣＯ３，可使阻滞因子Ｒ减小，说明ＣａＣＯ３是与土壤磷反应的主要基质。（２）温度升高有利于土柱“阻滞”磷素，证实了磷素与土壤反应是吸热反应；（３）ＣＸＴＦＩＴ程序用于计算磷运移参数具有可行性，且该程序计算的参数是根据穿透曲线ＢＴＣ拟合而得，更能反映实际情况。

By using the 32P isotopic tracer method, experiments have been conducted toinvestigate phosphorus transport in three different forms of four types of soils inShaanxi Province. It is found that: (1) Phosphorus can hardly break through the soilcolumn in experiment as the retardation factor, R, is larger than 1 in most cases,particularly in soils rich in clays and calcium carbonate. After eliminating CaCO3 fromthe soil, the value of R will decrease. (2) While raising temperature makes the valueof R increase and the value of diffusion-dispersion coefficient, D, decrease; and (3) Itis viable to use the CXTFIT program for calculation of phosphorus transportparameters.