中文摘要：

利用PM公式,结合托勒、野牛沟、祁连和门源站的气象要素数据,完成了对祁连山南坡地区潜在蒸散量的估算,并对其年际和年内的变化特征及其影响因素进行了分析.结果显示,1960-2012年祁连山南坡地区潜在蒸散量多年平均值为790.47mm/a^（-1）,变化范围为725.03mm/a^（-1）-834.98mm/a^（-1）,呈现波动增加的趋势,增加速率为0.46mm/a.托勒、野牛沟和祁连三个站点的潜在蒸散量呈现增加的趋势,门源站则呈现降低的趋势.祁连山南坡年内潜在蒸散量呈现明显的单峰模式,夏季蒸散量最大,占全年总量的42.04%,随之是春季、秋季和冬季,冬季的潜在蒸散量最少为66.09mm.1960-2012年祁连山南坡地区潜在蒸散量的最大影响因子为日最高温和风速,基本呈现极显著正相关性;湿度的影响性也较大,为极显著负相关影响因子.年内春夏秋冬各季节潜在蒸散量最大的影响因子分别是最高温、湿度、湿度和风速.

英文摘要：

This article calculates the reference evapotranspiration in southern slope of Qilian Mountains by using the Penman—Monteith method and the meteorological data between 1960-2012,and complete the analysis of the variation characteristics and impact factors of reference evapotranspiration.The result showed,the annual reference evapotranspiration was 790.47mm/a~（-1）,variated from 725.03mm/a~（-1） to834.98mm/a~（-1）,have a volatility increasing trend,increase rate about 0.46mm/a.The reference evapotranspiration in Tuole,Yeniugou,Qilian three stations have an increasing trend,in Menyuan station have a decreasing trend.Monthly reference evapotranspiration in southern slope of Qilian Mountains have an obvious unimodal pattern;the reference evapotranspiration in summer was the biggest of the four seasons,count 42.04% of the year＇s reference evapotranspiration,following by the spring,autumn and winter.Winter has the least reference evapotranspiration about 66.09 mm.The daily maximum temperature and wind speed was the biggest impact factors of the reference evapotranspiration in southern slope of Qilian Mountains between 1960-2012,have a very significant positive correlation;humidity also has a very significant positive correlation.The biggest impact factors of the spring,summer,autumn and winter are the daily maximum temperature,humidity,humidity and wind speed,respectively.