中文摘要：

利用祁连山老虎沟地区海拔4200m气象观测站2010年的观测资料,采用FAO Penman-Monteith公式,再利用作物系数法,对高寒草甸生长季（5月22-9月22）的蒸散发量进行估算和分析。结果发现：研究期共有124天,蒸散发总量为238.3mm,日均为1.87mm·d^-1。生长初期、生长中期、生长末期的蒸散发总量依次为22.6mm,179.1mm,36.6mm,依次占研究期总量的8.4%,75.2%,15.3%。5月下旬至6月中旬,日均蒸散发量以较低水平缓慢上升;6月下旬迅速增加;6月末至7月中旬猛然回落;7月中旬至8月末,日均蒸散发量迅速上升且维持在较高水平;此后直到9月22日,缓慢减少。5-9月月蒸散发总量依次为6.6mm,46.4mm,74.5mm,77.6mm,33.1mm。

英文摘要：

Based on meteorological data of 4200 meters above sea level in zone of Laohugou in Qilian Mountains,using the FAO Penman- Monteith formula and the Crop Coefficie- nt method,the evapotranspiration（ ET） of alpine meadow during the growing season（ 05- 22 ～ 09- 22） was estimated and analyzed. Results shows that the total ET was 238. 3mm and the daily mean was 1. 87mm·d^-1 during the 124 days. In initial growing period,middle growing period and the end growing period,the ET was 22. 6mm,179. 1mm and 36. 6mm,respectively,and their proportions occupied 8. 4%,75. 2% and 15. 3% of the whole ET values,respectively. From late May to mid- June,the daily ET increased slowly with a lower level; in late June,it increased rapidly,but in the end of June to mid- July,it had a sudden drop; from mid- July to the end of August,it increased rapidly and with a high level; since then until September 22,it decreased slowly. From May to September,the total monthly evapotranspirations were 6. 6mm,46. 4mm,74. 5mm,77. 6mm,33. 1mm,respectively.