摘要
【目的】探究不同时间尺度下夏玉米蒸发蒸腾量的变化规律。【方法】试验在夏玉米3个生育阶段(出苗—拔节期、拔节—抽雄期、抽雄—灌浆期)分别设置3个灌水水平(充分灌溉:100%ET_(a);中度水分亏缺:80%ET_(a);重度水分亏缺:60%ET_(a)),其中ET_(a)为蒸渗仪实测的充分灌溉条件下的蒸发蒸腾量,采用正交试验设计,共9个处理(CK、T1、T2、T3、T4、T5、T6、T7处理和T8处理),其中CK为充分灌溉处理,其余处理为不同程度的亏缺灌溉处理,研究了不同生育期亏缺-复水对夏玉米不同时间尺度蒸发蒸腾量、产量和水分利用效率的影响。【结果】与CK相比,不同亏缺灌溉处理下夏玉米蒸发蒸散量均有所减少。T3处理复水后蒸发蒸腾量基本可以恢复至正常水平,而T5、T6处理和T7处理复水后均未恢复至正常水平。抽雄—灌浆期土壤含水率应保持在75%田间持水率以上,土壤含水率低于50%田间持水率时,夏玉米将停止生长。不同亏缺灌溉处理的产量相较于CK减少5.85%~32.25%,其中T3处理比CK减少5.85%,且T3处理水分利用效率最高(2.81 kg/m3),比CK增加了4.07%。【结论】在苗期实施中度水分亏缺,拔节—抽雄期充分灌溉,可以提高夏玉米的水分利用效率,同时不造成产量的显著减少。
【Objective】Deficit irrigation is a technology used widely in most arid and semi-arid regions to increase water use efficiency,but how to optimize the timing of and duration of the deficit remains elusive.The objective of this paper is to fill this gap for summer maize grown in the north of China.【Method】The field experiment compared three deficit irrigations by controlling the irrigation water amount at 100%(sufficient),80%(moderate deficit)and 60%(sever deficit)of the potential evapotranspiration measured from a lysimeter(ET_(a)).Each treatment irrigated the crop at emergence-jointing stage,jointing-tasseling stage,and tasseling-filling stage,respectively.Overall,there were nine treatments:moderate deficit irrigation at the jointing-filling stage(T1),severe deficit irrigation at the jointing-filling stage(T2),moderate deficit irrigation at the emergence-jointing and tasseling-filling stage(T3),moderate deficit irrigation at the emergence-tasseling stage and severe deficit irrigation at the tasselingfilling stage(T4),moderate deficit irrigation at the emergence-jointing stage and severe deficit irrigation at the jointing-tasseling stage(T5),severe deficit irrigation at the emergence-jointing and tasseling-filling stage(T6),severe deficit irrigation at the emergence-jointing stage and moderate deficit irrigation at jointing-tasseling stage(T7),severe deficit irrigation at the emergence-tasseling stage(T8),and moderate deficit at the tasseling-filling stage(T8).Sufficient irrigation in all stages was taken as the control(CK).In each treatment we measured the impact of rewatering on evapotranspiration,grain yield and water use efficiency of the crop.【Result】Compared with CK,deficit irrigation led to a decrease in evapotranspiration regardless of the stage it was imposed.Rewatering in T3 increased the evapotranspiration to a level comparable to that in CK.T5,T6 and T7 resulted in a permanent reduction in evapotranspiration even after rewatering.To avoid grain yield loss,the soil water content during the tasseling-filling stage should be maintained above 75%of the field capacity.The critical soil water was 50%of the field capacity,below which the water taken up by the crop was unable to sustain its growth.Deficit irrigation reduced the fruit yield by 5.85%~32.25%,compared to the CK,with T3 reducing the least(5.85%).T3 was thus most water-use efficient(2.81 kg/m^(3)),increasing water use efficiency by 4.07%compared to CK.【Conclusion】Moderate water deficit at the seedling stage and full irrigation at the jointing-tasseling stage were optimal to improve water use efficiency without significantly reducing grain yield of the maize.
作者
段伟娜
徐家屯
曹玉鑫
彭雄标
蔡焕杰
DUAN Weina;XU Jiatun;CAO Yuxin;PENG Xiongbiao;CAI Huanjie(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China;Institute of Water-saving Agriculture in Northwest China,Northwest A&F University,Yangling 712100,China;Key Laboratory of Agriculture Water and Soil Engineering,Ministry of Education,Northwest A&F University,Yangling 712100,China)
出处
《灌溉排水学报》
CSCD
北大核心
2022年第2期18-26,共9页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(51879223)
国家重点研发计划项目(2016YFC0400201)。
关键词
夏玉米
蒸发蒸腾
亏缺-复水
产量
水分利用效率
summer maize
evapotranspiration
deficit-rehydration
yield
water use efficiency
