时间尺度对农田灌溉设计保证率的影响  

Effect of time scales on probability of irrigation water requirement of farmland

作　　者：宰松梅 冯雪芳 仵峰 李陆生 Zai Songmei;Feng Xuefang;Wu Feng;Li Lusheng(School of Water Conservancy,North China University of Water Resources and Electric Power,Zhengzhou 450046,China;Henan Key Laboratory of Water-saving Agriculture,Zhengzhou 450046,China)

机构地区：[1]华北水利水电大学水利学院,郑州450046 [2]河南省节水农业重点实验室,郑州450046

出　　处：《农业工程学报》2018年第16期96-102,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家科技支撑计划课题(2015BAD24B02);国家重点研发计划课题(2016YFC0400103);河南省科技攻关计划项目(152102110094)

摘　　要：设计保证率是灌溉系统设计的重要参数之一,以年尺度为计算时段选择的典型年,存在对降雨的年调节估计过高的可能。该文以河南省郑州市1951—2015年的气象数据为基础,对其年降雨量、月降雨量及旬降雨量等进行排频计算,分析了不同灌溉设计保证率下对应典型年的降雨分布。以冬小麦、夏玉米需水关键期对应的4月、7月和8月为典型时段,研究了同一保证率下降雨的变化情况,并按照不同的计算时间尺度制订出相应的灌溉制度,讨论了时间尺度对灌溉定额及降雨利用量的影响。结果表明:1)在相同灌溉设计保证率下,各典型年、月和旬的降雨量均相差较大,同一月份的降雨量相差5倍以上;降水量的极差由大到小依次为年尺度、月尺度、旬尺度。2)利用水量平衡法,制订了不同时间尺度下典型年冬小麦-夏玉米连作的灌溉制度,在25%灌溉设计保证率下,季尺度下的年灌溉定额显著高于日尺度;与季、月和旬尺度相比,日尺度下的年灌溉定额分别降低了34%、23%和3%;偏干旱年灌溉定额随降水计算尺度减小而减小,但差异不明显。考虑不同的时间尺度具有不同的节水潜力和效果,完善灌溉排水工程中相应标准及其选取方法,选择合适的计算时长,既有利于落实灌溉设计保证率,又能提高各种水资源的利用率。The probability of irrigation water requirement is one of the most important designing parameters for an irrigation system.And the actual rainfall distribution affects the realization degree of probability of irrigation water requirement.There is a possibility that the annual regulation of rainfall resources is overestimated as the typical year is chosen by annual precipitation.In this paper,based on the meteorological data from 1951 to 2015 in Zhengzhou,Henan province,the frequency of annual rainfall,monthly rainfall,and ten-day rainfall were calculated respectively.And the rainfall distribution corresponding to typical years was analyzed under different probability of irrigation water requirement.Then the typical years were selected at different time scales,and the rainfall of typical years under the same probability of irrigation water requirement was compared and analyzed.Taking April,July and August corresponding to the critical periods for water demand of winter wheat and summer maize as the typical periods,the changes of rainfall under the same probability of irrigation water requirement were studied,and corresponding irrigation schedules were formulated according to different calculation time scales.The effect of time scales on irrigation quota and rainfall utilization was discussed.The results showed that:1)Under the same probability of irrigation water requirement,the annual rainfall in each typical year was similar,the month and ten-day rainfall in each typical year had a significant difference,which was more than 5 times in May.The magnitude of precipitation varied from the largest to the smallest as followed:the annual,monthly and ten-day scales.2)Using the water balance method,an annual irrigation schedule was formulated for typical winter wheat and summer maize under different time scales.Under the probability of irrigation water requirement at 25%,the annual irrigation quota under the seasonal scale was significantly higher than the daily scale.Compared with the seasonal,monthly,and ten-day scales

关 键 词：灌溉 降雨 农田 时间尺度 灌溉设计保证率 典型年 灌溉制度 

分 类 号：S274.1[农业科学—农业水土工程] TV93[农业科学—农业工程]