土壤磷运移研究

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.

STUDIES ON PHOSPHORUS TRANSPORT IN SOILS

By using the ³²P isotopic tracer method, experiments have been conducted to investigate phosphorus transport in three different forms of four types of soils in Shaanxi Province.It is found that: (1) Phosphorus can hardly break through the soil column 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 from the soil, the value of R will decrease.(2) While rising temperature makes the value of R increase and the value of diffusion-dispersion coefficient, D, decrease; and (3) It is viable to use the CXTFTT program for calculation of phosphorus transport parameters.