兴安盟参考作物腾发量计算方法的适用性评价

Applicability evaluation on calculation method of reference crop evapotranspiration in Hinggan League

【目的】探求适合兴安盟参考作物腾发量计算方法,为节约水资源、优化灌溉制度和农业生产节本增效提供有效途径。【方法】以兴安盟4个站点为例,利用Priestley-Taylor法(PT法)和Hargreaves-Samani法(HS法)2种ET0计算方法,计算了1973—2018年4个站点的参考作物腾发量,以FAO56 Penman-Monteith法(PM法)计算所得结果为标准,依据均方根误差(RMSE)和相对误差(RE)等指标,分别对2种方法计算结果在4个站点日、月和年序列的适用性进行评价。【结果】对于兴安盟来说,在日值尺度上可以选PT法替代PM法计算ET0,因为PT法和HS法与PM法的吻合最好,尤其是PT法,决定系数R2达到0.99以上;在不同时间尺度上采用PT法和HS法替代PM方法,RSEM日值>月值>年值;RE日值>月值>年值。【结论】在气象资料缺失的情况下,兴安盟可以采用日值数据应用PT法和HS法计算参考作物腾发量。

【Objective】To provide an effective way for saving water resources,optimizing irrigation system and saving cost and increasing efficiency in agricultural production,by the suitable calculation method of Reference Crop Evapotranspiration(ET0) in Hinggan League,Inner Mongolia. 【Methods】Based on the data of four weather stations in Hinggan League,the daily ET0 values from 1973 to 2018 were calculated by using Priestley-Taylor method(PT method) and Hargreaves-Samani method(HS method).According to the Root Mean Square Error(RMSE) and Relative Error(RE),the applicability of the calculation results by PT method and HS method in the daily,monthly and annual time series in different weather stations were evaluated,taking ET0 value calculated by FAO56 Penman-Monteith method(PM method) as standard. 【Results】In Hinggan League,PT method and HS method could replace PM method to calculate ET0 in different time scales,and RSEM daily value>monthly value>annual value,RE daily value >monthly value >annual value.On the daily scale,the results of PT method and HS method were the most close to those of PM method,especially the determination coefficient R2 of PT method was more than 0.99. 【Conclusion】In the absence of meteorological data,the daily data could be used to calculate ET0 in Hinggan League by PT method and HS method.