Through the observation of soil water and salt in the farmland of spring maize under mulched drip irrigation in Hexi Region of Gansu Province,the characteristics of soil moisture and salt dynamic change,and the yield and water use efficiency of maize were analyzed.The results showed that the distribution of soil moisture content in different soil profiles at different growth stages was opposite to that of salt content,i.e.,in the soil profiles where there was a high salt content,there was a low moisture content.The salt accumulation at the imerval of drip pipes was significantly higher than that at the interval of emitters.Under the irrigation quota of 480 m3· hm-2,the irrigated water moved significantly along vertical direction and the deep leakage was remarkable;under the irrigation quota of 420 m3· hm-2,the irrigated water moved significantly along horizontal direction in different depth,being beneficial to the absorption and utilization of crop.Mulched drip irrigation could significantly reduce soil salt content in 0 ～ 40 cm profile,while the profile of 40 ～100 cm was the accumulating zone of salt during drip process.Under the irrigation quota of 420 m3· hm-2,the yield and water use efficiency of spring maize were relatively high.Therefore,from the viewpoim of water and salt environment as well as efficient water-saving,the benefit of the irrigation quota of 420 m3 ·hm-2 was the best.%通过对甘肃河西地区膜下滴灌春玉米种植条件下土壤水分、盐分的观测,分析了膜下滴灌春玉米生育期土壤水分、盐分动态变化及其产量和水分利用效率.结果表明:不同生育期,同一土层深度,土壤水分含量高低分布与土壤盐分含量高低分布相反,均表现出土壤不同深度盐分含量高的区域相应水分含量低,滴灌带之间土壤盐分积累较滴头之间显著;灌水定额480 m3·hm-2处理,灌溉水分在土层纵向运移显著,深层渗漏明显,灌水定额420 m3·hm-2处理,灌溉水在土壤不同深度横向层面运移显著,有利于作物吸收利用;膜下滴灌能够在滴水过程中明显降低土壤表层0～40 cm盐分含量,土壤下层40～ 100 cm为盐分聚集区域;灌水定额420m3·hm-2处理,春玉米产量构成和水分利用效率较高.从作物生长水盐环境及高效节水的角度出发,灌水定额420m3·hm-2处理的效益最优.
展开▼
