采用室内土柱实验研究了单施磷酸二氢铵(MAP)、磷酸二氢铵配施草酸(MAP+OA)和包膜磷酸二氢铵(包膜MAP)3种施肥模式下磷在潮土和水稻土肥际微域中的迁移和形态转化。结果表明,磷在土壤中的迁移距离较短,磷在潮土中的迁移距离较水稻土短,配施草酸处理可增加磷在土壤中的迁移距离,包膜MAP处理磷的迁移距离最短且释放量少。磷在施肥60 d内的迁移量较大,然后只发生少量迁移,迁移进入土壤的磷60.2%~80.3%被吸附固定,15.4%~42.9%仍以有效态存在,配施草酸处理可降低土壤对磷的固定作用,包膜MAP处理缓慢释放磷肥可能会增强土壤对磷的固定作用。
In this paper,effects of three fertilization on phosphorus transformation and movement in fertilizer microsites in calcareous and paddy soils were studied by an incubation experiment using soil column.The phosphorus movement distance of MAP treatment was short in paddy soil at about 50 mm and was shorter in calcareous soil.By adding OA,phosphorus had a longer movement distance.Coated MAP treatment decreased the release amount and movement distance of phosphorus.Comparing the migration quantity of 60 d and 120 d treatments,most phosphorus migrated in the first 60 days while 60.2%~80.3% of them were absorbed by soil and 15.4%~43.9% of them existed as available phosphorus.Phosphorus absorption and fixation were lowered by adding OA.Coated MAP treatment might strengthened the fixation of soil because of the slow-released phosphorus.