考虑辐射改进Hargreaves模型计算川中丘陵区参考作物蒸散量  

Modifying Hargreaves model considering radiation to calculate reference crop evapotranspiration in hilly area of central Sichuan Basin

作　　者：贾悦[1] 崔宁博[1,2] 魏新平[1] 龚道枝[3] 胡笑涛[4] 

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室/水利水电学院,成都610065 [2]南方丘区节水农业研究四川省重点实验室,成都610066 [3]中国农业科学院农业环境与可持续发展研究所作物高效用水与抗灾减损国家工程实验室,北京100081 [4]西北农林科技大学旱区农业水土工程教育部重点实验室,杨凌712100

出　　处：《农业工程学报》2016年第21期152-160,共9页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家科技支撑计划(2015BAD24B01);农业部旱作节水农业重点实验室基金(HZJSNY201502);四川省软科学研究计划(2015ZR0157)

摘　　要：为提高Hargreaves-Samani（H-S）模型对参考作物蒸散量（reference crop evapotranspiration,ET0）的计算精度,利用川中丘陵区13个代表站点1954-2013年近60 a逐日数据,依据贝叶斯原理并考虑辐射的影响对H-S模型进行改进,并以Penman-Monteith（P-M）模型为标准,对其在川中丘陵区的适用性进行评价。结果表明：1）H-S改进模型与P-M模型ET0计算结果变化趋势基本一致;2）与H-S模型相比,在3个区域H-S改进模型计算的ET0旬值平均绝对误差分别由0.93、0.95、0.93 mm/d下降到0.15、0.19、0.28 mm/d,且3个区域ET0旬值拟合方程斜率分别由1.45、1.39、1.45变为0.89、0.94、0.90,Kendall一致系数由0.70、0.80、0.82提高到0.88、0.92、0.94,拟合效果与计算精度均明显提高;3）在3-10月的作物主要生长期,3个区域ET0月值平均绝对误差分别由0.89、1.14、1.28 mm/d下降到0.46、0.29、0.21 mm/d,ET0月值回归拟合方程斜率及一致性均明显提高;4）H-S改进模型随海拔升高计算精度有所降低,H-S改进模型全年内计算精度最大可提高47%,尤其在作物主要生长期,精度最大提高了48%。因此,H-S改进模型可显著提高ET0计算精度,在海拔较低的区域尤为明显,可作为川中丘陵区ET0计算的简化推荐模型。Reference crop evapotranspiration（ET0） is an important parameter in water cycle and water balance. Accurate estimation of ET0 becomes vital in planning and optimizing irrigation schedules and irrigation system management. Numerous methods have been proposed for estimating ET0, among which the Penman-Monteith（P-M） method recommended by Food and Agriculture Organization of the United Nations（FAO） in 1998 provides the most accurate results across the world wherever in arid or humid environment. But the main problems when computing ET0 by the P-M method are its complicated nonlinear process and requirements of many climatic variables. Thus, there is an urgent need to develop a much simpler and more appropriate method in areas with limited data, such as the Hargreaves-Samani（H-S） method. In order to improve the ET0 calculation accuracy of the H-S method, in this research the daily data of 13 representative meteorological stations from 1954 to 2013 in hilly area of central Sichuan was used to calculate the ET0. The H-S method was modified based on the Bayesian principle and the impact of the radiation, and at the same time the accuracy of the modified method was evaluated. The result showed that in ZoneⅠ the parameter a was 0.915, in Zone Ⅱ was 0.922, in Zone Ⅲ was 0.912, and the parameter b was the function of radiation. The trend of the modified method＇s computing result was similar to the P-M method and both showed a parabolic shape. Compared with the H-S method, the average absolute error of ten-day ET0 with the modified H-S method decreased from 0.93 to 0.15 mm/d in Zone Ⅰ, from 0.95 to 0.19 mm/d in Zone Ⅱ and from 0.93 to 0.28 mm/d in Zone Ⅲ. The fitting equation slope of ten-day ET0 was 0.89, 0.94 and 0.90 respectively in these areas using the modified method, and the calculation accuracy was enhanced remarkably. During the period between March and October, the average absolute error of monthly ET0 decreased from 0.89 to 0.46 mm/d in ZoneⅠ, from 1.14 to 0.29 mm/d in ZoneⅡ and fr

关 键 词：蒸散 模型 作物 辐射 参考作物蒸散量 Hargreaves-Samani模型 贝叶斯原理 适用性评价 

分 类 号：S161.4[农业科学—农业气象学]