【摘要】 为对气候变化下不同时间尺度参考作物腾发量（ET₀）的变化规律及其主控因子进行研究,为北京地区制定作物灌溉制度提供参考。基于1970—2019年北京市的逐日气象资料,对不同时间尺度上ET₀进行趋势分析,并采用相关分析与因子分析相结合的方法确定ET₀主控因子。研究表明:（1）日尺度下,ET₀年内变化呈双峰型曲线变化,第一峰值为5.32 mm/d,第二峰值为3.93 mm/d,年内均值为2.78 mm/d;月尺度下,ET₀呈单峰变化趋势,1月份最低,5月份最高,分别为31.3、148.2 mm; ET₀的年际变化范围为901.33～1 095.47 mm,年际变化倾向率为6.32 mm/（10年）。（2）各气象因子与ET₀的相关性随年内月份的不同而表现出差异性,仅采用相关分析法难以真实厘清各个气象因子对ET₀的影响作用;采用因子分析后可知,影响北京地区夏季和春季ET₀的主控因子分别是温度辐射因子和湿度日照风速因子;结合相关性分析表明,北京地区ET₀增加趋势主要是气候升温导致的。本研究对气候变化下北京地区未来农业用水管理具有实际指导意义。更多还原

【Abstract】 To study the change rule and main controlling factors of reference crop evapotranspiration（ET₀） in different time scales under climate change, based on the daily meteorological data from 1970 to 2019, the trend analysis of ET₀ on different time scales was carried out, and the main controlling factors of ET₀ were determined by combining correlation analysis and factor analysis. Studies show that:（1） ET₀ showed a bimodal curve in the diurnal scale, with the first peak of 5.32 mm/d, the second peak of 3.93 mm/d, and the annual mean of 2.78 mm/d.ET₀ showed a unimodal trend at the monthly scale, with the lowest value in January and the highest value in May, which were 31.3 mm and 148.2 mm, respectively.The interannual variation of ET₀ ranges from 901.33 to 1 095.47 mm, and its interannual variation tendency rate is 6.32 mm every 10 years.（2） The correlation between the meteorological factors and ET₀ varies with the month of the year. It is difficult to make clear the influence of the meteorological factors on ET₀ by the correlation analysis method only. Factor analysis showed that temperature radiation factor and humidity sunshine wind speed factor were dominant in summer and spring respectively. The correlation analysis shows that the increasing trend of ET₀ in Beijing is mainly caused by the warming under climate change. This study has practical guiding significance for future agricultural water management in Beijing under climate change.更多还原