Effects of different water-nitrogen conditions on yield and water and nitrogen use efficiency were studied by field experiment in marginal oasis regions of Heihe River Basin. The results showed that: Compared with that of high water and fertilizer( W1 F1 ), the other treatments decreased plant height, increased root-shoot ratio and the root depth (except of W1F2), among which the treatment of low water and nitrogen (W3F2) caused most remarkable change in plant height, root-shoot ratio and the root depth, and the plant height decreased by 14.1%, the root depth and root-shoot ratio increased by 13.3% and 88.9%, respectively. The above-ground biomass yield increased with nitrogen amount increasing in same irrigation amount, but the effect on production increase was more significant in low irrigation amount with nitrogen amount increasing; it also increased with irrigation amount increasing in same nitrogen amount, but the effect on production increase was the best in low fertilizer condition along with irrigation amount increasing. Water use efficiency presented decreasing trend with the increase of irrigation anount in two nitrogen conditions, but nitrogen use efficiency showed increasing trend. The above-ground bionass yield and total biomass yield in high water and fertilizer were maximum, and the values were 87 t/hm2 and 99 t/hm2 , respectively. The low water and fertilizer were opposite to it, and the values were 73 t/hm2 and 90 t/hm2, but they had no significant difference, while the nitrogen use efficiency in W3F2 increased by 13.2% compared with W1F1. All these indicated that the high biomass yield and high water and nitrogen use efficiency could be acquired in the marginal oasis regions through adopting irrigation amount of 7 760 m3/hm2 ,accompanied by nitrogen fertilizer amount of 220 kg/hm2.%在黑河中游边缘绿洲地区,通过田间试验,研究不同水氮组合对青贮玉米产量及水分和氮肥利用效率的影响.结果表明:与高水氮(W1F1)相比,其它各处理均使青贮玉米的株高降低、根冠比增大,根深增加(除W1F2外),其中低水肥(W3F2)的株高、根深、根冠比变化均最大,株高降低了14.1%,根深和根冠比增加了13.3%和88.9%.在同一灌溉量下,随施氮量增加青贮玉米的地上生物产量均提高,但在低灌溉处理条件下随施氮量的增加其增产效果相对明显;同一施氮量下,随着灌溉量的增加,青贮玉米的地上生物鲜重也均提高,但在低肥处理下,随灌溉量的增加青贮玉米生物产量的增加效果最好.两种氮肥水平下,水分利用效率均随灌溉量的增加呈减少的变化趋势,但氮肥利用效率却随灌溉量的增加呈增加的变化趋势.6种水肥组合方式下,高水肥(W1F1)的地上生物鲜重、总生物鲜重均最高,其值分别为87 t/hm2、99 t/hm2,低水肥(W3F2)地上生物鲜重、总生物鲜重最低,其值分别为73t/hm2和90 t/hm2,但无显著差异,且W3F2氮肥利用效率比W1F1提高了13.2%.以上结果表明,在边缘绿洲区青贮玉米生产中,采用生育期灌水7 760 m3/hm2与220 kg/hm2的施氮组合能获得较高的生物产量和水分、氮肥利用效率.
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