１９９１ ～１９９５ 年，在陇东半湿润易旱地区以冬小麦为供试作物，通过氮、磷、有机肥三因素试验从生态学角度探讨了施肥对提高水分利用效率的机理。结果表明，施肥，尤其是氮磷化肥配施，可明显促进冬小麦根系生长，扩大觅水空间；氮磷化肥配施具有时效互补性和功能互补性；与不施肥处理相比，施肥处理蒸散量仅提高了５４ ％ ，而产量和水分利用效率却分别提高了９２８ ％ 和７９７ ％ ；施肥促进了冬小麦冠层发育，增加了蒸腾量，而减少了蒸发量，从而提高了腾／发比，使水分利用效率及水分生产力大幅度提高。 From 1991 to 1995, winter wheat was used as tested crop in semi-humid and drought-prone area of ​​Longdong. The mechanism of fertilization on water use efficiency was discussed from three aspects of ecological factors including nitrogen, phosphorus and organic fertilizer. The results showed that fertilization, especially nitrogen and phosphorus fertilizers, could significantly promote the root growth of winter wheat and expand the water seeking space. The application of nitrogen and phosphorus fertilizers was complementary to each other and functionally complementary. Compared with no fertilization, Only increased by 54%, while the yield and water use efficiency increased by 928% and 797% respectively. Fertilization promoted the development of canopy in winter wheat and increased the transpiration and decreased the evaporation, thus increasing the yield Teng / Fat ratio, so that water use efficiency and water productivity increased significantly.