在甘肃河西绿洲灌区通过田间试验，研究了水氮耦合两因素共同作用下对春玉米水分利用率的影响。研究结果表明:全生育期施氮量为360 kg/hm2、灌水量为5 700 m3/hm2条件下，玉米水分利用效率最高，为30.4 kg/(hm2·mm)，比玉米水分利用效率最低的全生育期不施氮、灌水量为7 200 m3/hm2处理的24.1 kg/(hm2·mm)高26.0%。全生育期施氮量为540 kg/hm2、灌水量为6 450 m3/hm2条件下，玉米经济产量最高，为15 060 kg/hm2，比玉米经济产量最低的全生育期不施氮、灌水量为5 700 m3/hm2处理的12 204 kg/hm2高23.4%。在全生育期施氮540 kg/hm2、灌水6 450 m3/hm2条件下，既可获得高产又可获得较高的水分利用效率。

In Hexi oasis irrigation district，we through the field experiment to study effects of different water and nitrogen coupling on spring corn of the water use efficiency. The result shows that in the whole growth period under the condition of the nitrogen level is 360 kg/hm2 and irrigation water is 5 700 m3/hm2， the highest corn water use efficiency is 30.4 kg/(hm2·mm)， more than no nitrogen level and irrigation water is 7 200 m3/hm2 in the whole stages is 26%. In the whole growth period， under the condition of nitrogen level is 540 kg/hm2 and irrigation water is 6 450 m3/hm2， the highest economic output of corn is 15 060 kg/hm2， more than no nitrogen level and irrigation water is 5 700 m3/hm2 in the whole stages is 23.4%. In the whole growth period， under the condition of he nitrogen level is 540 kg/hm2 and irrigation water is 6 450 m3/hm2， can obtain higher yield and higher water use efficiency.

S513