不同灌溉处理下冬小麦水平衡与灌溉增产效率研究

Water balance and yield-increasing efficiency of irrigation of winter wheat under different irrigation schemes

水资源是华北平原冬小麦、夏玉米种植区最重要的生产制约因素,农业水资源高效利用具有重大的社会需要。通过设置冬小麦不同灌溉处理,分析了各处理的水分平衡、产量和灌溉增产效率。结果显示:1)不同灌溉处理具有不同的水分平衡过程,雨养农田、充分灌溉处理、返青水胁迫处理、拔节抽穗水胁迫处理和灌浆水胁迫处理的蒸散量分别为251±58 mm、482±48 mm、352±44 mm、388±22 mm和324±53 mm;2)灌溉量对于小麦产量的增加具有明显的正效应,拔节-抽穗水胁迫对作物产量有较大影响,灌浆水胁迫和返青水胁迫均没有对小麦产量造成明显影响;雨养农业的经济产量为2 950±635 kg.hm-2,充分灌溉下的经济产量约为5 994±994 kg.hm-2;冬小麦返青期、拔节抽穗期、灌浆期施加适度的水分胁迫,产量分别为5 163±885 kg.hm-2、5 047±1 180 kg.hm-2、5 249±975 kg.hm-2,与充分灌溉相比,没有明显的产量下降;3)小麦的灌溉增产效率存在明显的年际差异,在丰水年或特丰水年,灌溉增产效率为1.9 kg.m-3,在枯水年为0.4 kg.m-3,平水年为1.6 kg.m-3。

Water is the most important limiting factor of wheat-maize double cropping system＇s production in the North China Plain（NCP）.Water-saving agriculture is critical for social stability and sustainable economic development.To elevate irrigation efficiency in NCP,field experiments were conducted during three growing seasons of winter wheat at the Luancheng Agro-Ecosystem Experi-mental Station of Chinese Academy of Sciences.Five irrigation schemes were designed in winter wheat seasons in the study area.The irrigation schemes included rainfed scheme（A） with no irrigation throughout the growing season,well irrigation scheme（B） with 100% field-capacity irrigation at all the stages,recovery water-stress irrigation scheme（C） with no irrigation at recovering stage and 80% field-capacity irrigation at all other growth stages,jointing-heading water-stress irrigation scheme（D） with no irrigation at jointing-heading stage and 80% field-capacity irrigation at all other stages,and then grain-filling water-stress irrigation scheme（E） with no irrigation at grain-filling stage and 80% field-capacity irrigation at all other stages.All the treatments had 3-4 replicates and irrigation was only done when moisture in the 0-100 cm soil depth was less than 65% of field capacity.The field irrigation experi-ments were conducted from October 2007 through June 2010.The results showed that evapotranspiration（ET） for treatments A,B,C,D and E were 251±58 mm,482±48 mm,352±44 mm,388±22 mm and 324±53 mm,respectively.The volume of irrigation was posi-tively related to yield in all the treatments.Yields for treatments A,B,C,D and E were 2 950±635 kg-hm-2,5 994±994 kg-hm-2,5 163±885 kg-hm-2,5 047±1 180 kg-hm-2 and 5 249±975 kg-hm-2,respectively.Irrigation efficiency varied from year to year in relation to precipitation trend.The effect of water on yield was therefore significantly different for the three years.In wet years,irri-gation efficiency was 1.9 kg-m-3,it was 0.4 kg-m-3 in dry years and 1.6 kg-m-3 in normal years.