【摘要】 通过对黑河流域大满灌区灌溉试验,测定了不同生育年龄甘农3号苜蓿Medecago sativacv.GannongNo.3地上生物量,经统计分析建立了苜蓿地上生物量年际动态和不同生育年内各茬间动态变化规律,结果表明,不同年际间各茬产量在不同水分处理下水分利用效率存在明显差异。不同水分处理下产量的变化呈高-低-高的“S”型变化,确定了苜蓿地的高效灌溉时期为现蕾-开花期,优化灌溉定额为520 mm,为苜蓿高产节水灌溉模式提供了理论依据。更多还原

【Abstract】 Based on the experimentation of alfalfa(Medicago sativa cv.Gannong No.3) in Daman irrigation region of Zhangye.Above ground biomass was measured for alfalfa crops of different ages and harvests,above ground biomass dynamics were formulated.The results showed that there were distinct differences in soil water content and water use efficiency among different stages,having a"S"change which is high-low-high in the 1st harvest.Effective irrigation time and amount were determined for alfalfa crops in different stages,the results showed that the critical water demand stage was budding to flowering stage.The appropriate irrigation capacity for alfalfa in Zhangye prefecture was 520 mm.The conclusion could provide some scientific basis for further development of local grass production and water-saving irrigation model.更多还原