【摘要】 本文采用对比法对沈阳农业大学长期（１９８９～１９９２）地膜覆盖定位试验地棕壤中磷素的平衡与变化情况进行了全面研究．结果表明：覆膜之后土壤磷移出量增多而积累量减少。地膜覆盖降低了土壤无机磷和有机磷的含量，其中下降幅度最大的是Ａｌ－Ｐ形态磷和中等活性有机磷；而Ｆｅ－Ｐ和Ｃａ－Ｐ形态磷含量有所提高．覆膜后土壤中吸附磷和保持磷的数量下降，而解吸磷能力增强、试验结果还表明增施有机肥能显著提高上壤有机磷和无机磷的含量以及提高磷的解吸能力，增加幅度最大的是Ａｌ－Ｐ和中等活性有机磷。因此，增施有机肥是恢复和提高覆膜后土壤磷素肥力的较好措施。更多还原

【Abstract】 This paper deals with the characteristics of phosphorus in the long-term plastic film mulching soil (a loamy brown earth derived from loesslike parent material ) at Shenyang Agricultural University in 1987￣1992. The main results showed that more phosphorus was uptaken by plant and little accumulated in covered plots. The amounts of soil inorganic and organic phosphorus were reduced in the covered treatments, cspecially the Al-P and moderately liable P, whereas the Fe-P and Ca-p increasedto some extent. The capabilities of adsorption and conservation for added phosphorus declined in the shceted treactments but the esorption was enhanced, which could increase the effcetivness of phosphorus in these treatments. In addition, the application of organic material and manure could improve the levels of phosphorus in the plots covered with plastic film.更多还原