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本文应用放射性同位素示踪法,研究了黄土区几种土壤中磷素的扩散过程、影响因素以及其对作物有效性的关系。结果表明:。1.磷素在土壤中一般仅能扩散3—4cm。10—15天乃基本达到平衡。各种类型土壤的磷素扩散有明显的差别,这与土壤的粘粒含量有关。磷素的扩散系数为7×10~(-8)—6×10~(-7)cm~2/s;2.土壤水分和厩肥均能明显地增进磷素在土壤中的扩散作用,而无机盐的作用则相反;3.小麦和玉米幼苗从黄绵土中吸收的示踪磷比从红油土中吸收的高1.5倍。
In this paper, radioactive isotope tracer method was used to study the process of phosphorus diffusion in several soils and their influencing factors and their relationship with crop availability. The results show:. 1. Phosphorus in the soil generally only spread 3-4cm. 10-15 days is the basic balance. There is a clear difference in phosphorus diffusion among various types of soils, which is related to the amount of clay in the soil. The diffusion coefficient of phosphorus was 7 × 10 -8 -6 × 10 -7 cm -2 / s. 2. Both soil moisture and manure could obviously promote the diffusion of phosphorus in the soil, The role of inorganic salts is the opposite; 3. Wheat and corn seedlings absorbed from loessial soil tracer phosphorus 1.5 times higher than absorbed from the red soil.