基于多层次模糊评判法对小麦调亏沟灌方式的分析

Analysis of regulated deficit furrow irrigation mode of wheat based on fuzzy evaluation

为选择适宜的冬小麦农田沟灌方式实现水分高效利用,本研究运用多层次的模糊综合评判法,通过构建多层次多因素的指标体系对不同沟灌方式进行评价。在主观求取权重的基础上,运用熵权法进行修正,使得权重结果更符合实际情况,提高评判结果的准确性。本研究设置隔沟交替灌溉和常规沟灌2种沟灌方式,同时设置60%、70%、80%3个水分控制下限,研究不同处理对冬小麦产量和水分利用效率的影响,筛选出兼顾冬小麦产量和水分利用效率的调亏沟灌方式。结果表明,随着水分控制下限的增加,冬小麦在2种沟灌方式下产量亦随之增加,但水分利用效率和经济系数在水分控制下限为80%时降低。常规沟灌和隔沟交替灌溉2种沟灌方式下,水分控制下限为70%时冬小麦水分利用效率最大(分别为1.86 kg/m^(3)和1.90 kg/m^(3))。说明,适度水分亏缺有利于水分利用效率的提高,隔沟交替灌溉可大幅降低灌溉耗水总量,因此在灌溉水充足的地区推荐采用常规沟灌,在水资源紧缺的地区则适合使用隔沟交替灌溉方式。

In order to select appropriate furrow irrigation methods for winter wheat and achieve efficient water use,the multi-level fuzzy comprehensive evaluation method was used to evaluate different furrow irrigation modes by constructing a multi-level and multi-factor index system.On the basis of subjective weighting,the entropy weight method was used to make corrections,so that the weighting results were more in line with the actual situation,and the accuracy of evaluation results was increased.In this study,two furrow irrigation methods were applied,including the conventional furrow irrigation and alternative furrow irrigation.Meanwhile,three lower limits of soil moisture(60%,70%,80%)were set.Effects of different treatments on winter wheat yield and water use efficiency were studied to screen out the regulated deficit furrow irrigation method considering the yield,and water use efficiency.The results showed that the winter wheat yield increased with the increase of irrigation amount under two irrigation methods,but the water use efficiency and economic coefficient decreased when the lower limit of soil moisture was 80%.When the lower limit of soil moisture was 70%,the water use efficiency of winter wheat was the highest under conventional furrow irrigation and alternative furrow irrigation(1.86 kg/hm^(3) and 1.90 kg/hm^(3),respectively).The moderate water deficit is beneficial to the improvement of water use efficiency,and the alternative furrow irrigation can greatly reduce the total irrigation water consumption.Therefore,conventional furrow irrigation is recommended in areas with sufficient irrigation water,and alternative furrow irrigation is suitable in areas with scarce water resources.