节水减氮对甘肃河西灌区青贮玉米生长及水氮利用效率的影响

Effects of Water Saving and Nitrogen Reduction on Growth and Water and Nitrogen Use Efficiency of Silage Maize in Hexi Irrigation Area of Gansu Province

针对当前青贮玉米(Zea mays L.)生产中灌溉水资源不足和施氮过量的问题,本研究以河西灌区规模化种植青贮玉米为研究对象,布设4个灌水水平(W_(1),6150 m^(3)·hm^(-2);W_(2),5535 m^(3)·hm^(-2);W_(3),4920 m^(3)·hm^(-2);W_(4),4305 m 3·hm^(-2))和4个施氮水平(N_(1),311 kg·hm^(-2);N_(2),279.9 kg·hm^(-2);N 3,248.8 kg·hm^(-2);N 4,217.7 kg·hm^(-2))的二因素田间实验,探究不同节水减氮对青贮玉米生长及水氮利用效率的影响。结果表明:W 2处理青贮玉米的总耗水量与W_(1)无显著差异;W_(2)N_(2)处理产量与W_(1)N_(1)处理无显著差异,但较其它节水减氮处理提高了青贮玉米产量;与W_(1)相比,W_(2)处理的水分利用效率(WUE)、灌溉水利用效率(IWUE)分别提高4.6%,9.1%;与N_(1)相比,N_(2)处理的IWUE、氮肥偏生产力(PFP)分别增加4.2%,17.9%。因此,青贮玉米节水10%减氮10%处理可提高WUE、IWUE和PFP,是适宜于河西灌区青贮玉米水氮高效利用的可行管理措施。

Aiming at tackling the problems of insufficient irrigation water resources and excessive nitrogen application in the production of silage maize(Zea mays L.),this study took large-scale planting of silage maize in Hexi Irrigation Area as the research object,and a two-factor field experiment of the four levels of W 1,6150 m^(3)·hm^(-2);W_(2),5535 m^(3)·hm^(-2);W_(3),4920 m^(3)·hm^(-2);W_(4),4305 m^(3)·hm^(-2)irrigation and four nitrogen levels of N 1,311 kg·hm^(-2);N_(2),279.9 kg·hm^(-2);N 3,248.8 kg·hm^(-2);N_(4),217.7 kg·hm^(-2)application was conducted to explore the effects of different water saving and nitrogen reduction on silage maize growth and water and nitrogen utilization efficiency.The results showed that there was no significant difference in total water consumption between W_(2)and W_(1);there was no significant difference of the yield of silage maize between W_(2)N_(2) and W_(1)N_(1) treatments,but the maize yield in W_(2)N_(2) was higher compared with other water saving and nitrogen reducing treatments.Compared with W_(1) irrigation treatment,the water use efficiency(WUE)and irrigation water use efficiency(IWUE)of W_(2) irrigation were higher by 4.6%and 9.1%.Compared with N_(1) application treatment,the IWUE and nitrogen partial productivity(PFP)of N_(2) application higher by 4.2% and 17.9%,respectively.Therefore,10% of irrigation saving and nitrogen fertilizer reduction rate of silage maize could increase WUE,IWUE and PFP of the crop,which might be a feasible management measure suitable to silage maize for efficient utilization of water and nitrogen in Hexi Irrigation Area.