普洱市近59a参考作物蒸散量时空变化特征

Variation Characteristics of Reference Crop Evapotranspiration in Pu’er City in Recent 59 Years

利用普洱市地面气象观测站1959~2017年逐日气象资料,采用FAO 56-Penman-Monteith(FAO-PM)法、距平分析、回归分析和地理信息技术研究了普洱市参考作物蒸散量(reference crop evapotranspiration,ET0)的年代际、年际和年内不同时间尺度下时空变化特征。结果表明:普洱市平均ET0年代均值2011~2017年最大,为1196.2 mm,1959~1960年最小,为1101.0 mm;ET0年代均值高值区在普洱西部南侧,低值区在普洱西部西盟北侧、北部景东以北及东南部江城东部边缘。普洱市各气象站ET0年际变化均呈波动性上升趋势,其中西盟站平均ET0年值年际波动最大,江城站ET0年值年际波动最小。多年平均ET0年值空间分布景东、江城、澜沧以西北地区较小,孟连和澜沧的南部较大。各气象站ET0季节均值春季最大,夏季次之,秋、冬季逐渐减小,各气象站多年ET0月均值的变化趋势基本一致,曲线均为双峰型,最高峰值出现在4、5月,第二峰值出现在8、9月。

FAO 56-Penman-Monteith(FAO-PM)method,distance average analysis,regression analysis and geographical information technology were adopted to analyze temporal characteristics of reference crop evapotranspiration(ET0)in Pu'er City in three time scale:the decadal,inter-annual andannual,by using dailymeteorological data from 1959 to 2017 providedby Pu'er City SurfaceMeteorological Observatory.The results showthat the average ET0 age in Pu'er City was the largest in 2011 to 2017,with a maximum of 1196.2 mm,the smallest in 1959 to 1960,and the minimum value was 1101.0 mm.The ET0 mean high value area was on the south side of the western part of Pu'er City,and the low value area was on the north side of Ximeng in the west of Pu'er City,north of Jingdong in the north and the eastern edge of Jiangcheng in the southeast.The interannual variability of ET0 in all meteorological stations in Pu'er City showed a volatility trend.The annual volatility of the average ET0 value of Ximeng Station is the largest,and the annual volatility of ET0 of Jiangcheng Station is the smallest.The spatial distribution of the annual average ET0 annual value:Jingdong,Jiangcheng,and the northwest region are smaller,and the south of Menglian and the south of Lancang stations are larger.The average ET0 season of each station is the largest in spring,followed by summer,and gradually decreased in autumn and winter.The trend of the monthly average ET0 of each station is basically the same,the curves were bimodal,the highest peak appears in April and May,and the second peak appears in August and September.