泾惠渠灌区畦长对夏玉米耗水特性和产量影响

泾惠渠灌区中畦田规格参差不齐,灌区由于畦田过长而造成的灌溉水量浪费屡见不鲜,不仅没有形成高产而且极大的造成了水资源的浪费。通过大田与小区试验相结合,以当地农民习惯的灌溉方式为对照,设置3个灌溉畦长处理(80、120、240 m),每个处理设置3次重复,改水为80%。研究了灌溉畦长对夏玉米在生育期内的耗水特性和产量的影响,土壤水分分布与产量及其构成因素的关系等问题,选择出兼顾节水高产可行的最优畦长。研究结果表明:在生育期灌水后,80和120 m处理畦长内畦首、畦中和畦尾的土壤相对含水率较为均匀无显著差异,240 m处理畦长畦首、畦中和畦尾的土壤相对含水率产生显著性差异;80和120 m处理夏玉米在畦首、畦中和畦尾灌水均匀度较为平均且无显著差异,240 m畦长处理差异较为显著,且80 m畦长处理产量分布最为平均、平均水分利用效率最高产量为1.021 839万kg/hm2,水分利用效率为25.12 kg/(hm2·mm)。综合夏玉米产量及其分布、水分利用效率等因素,在泾惠渠灌区80 m的灌溉畦长是兼顾节水高产的最适宜畦长,该结论以期为泾惠渠灌区大田作物高产节水提供一定理论依据。

Effect of Field Border Length for Irrigation on Water Consumption Characteristics and Yield of Summer Maize in Jinghuiqu Irrigation District

The ridge border specifications of Jinghuiqu irrigation district are uneven.The waste of irrigation amount due to too long ridge border is common.In this experiment, the combination of cell test and field test is carried out with the irrigation methods used by local farmers as the control treatment;three furrow irrigation length (80, 120, 240 m) treatments are set, each treatment is repeated three times, and the water-changing degree is eighty percent.The effects of furrow irrigation border length on water consumption characteristics and yield of summer corn in the growth period, and the relations between soil moisture distribution with yield and its components are studied to select the best feasible border length considering both water-saving and high yield.The study results show that: after irrigation in the growth period, the difference of the soil water content among the head, middle and end of the furrow is unobvious for the treatments of 80 and 120 m furrow length, while that is significant for the treatment of 240 m length;the yield distribution of the 80 m length treatment is the most uniform, the average water use efficiency and the yield are is the highest as 25.12 and 18.39 kg/(hm+2·mm), respectively.Comprehensively considering the yield and its distribution of summer maize, the water use efficiency, the 80 m irrigation ridge border length is the most suitable length considering both water-saving and high yield for Jinghuiqu irrigation district.The study result will provide theoretical basis for the water-saving and high yield of field crops in Jinghuiqu irrigation district.