Alpine wetland ecosystems play significant roles in water regulation and regional ecological safety on the Qinghai-Tibet Plateau due to large water conservation potential. The knowledge of evapotranspiration (ET) in various alpine wetland ecosystems is of great significance for understanding the water balance of wetland ecosystems and carrying out eco-environment conservation. Therefore, two alpine wetland ecosystems as lakeside and headwater of Qinghai Lake basin were selected, and their ET characteristics and influencing factors were researched over two years. The daily ET in the lakeside ecosystem showed ‘double peak’ curve, and the headwater ecosystem showed the ‘multiple peak’ ET curve. The monthly ETs in two respective wetlands ranged from 9.88 to 111.56 mm and from 0.23 to 75.5 mm, respectively. The annual ET in the lakeside ecosystem was averagely 1.89 times more than that of the headwater. Stepwise multiple linear regressions indicated that monthly average net radiation (Rn) and leaf area index (LAI) explained 96% variance in monthly ET in the lakeside ecosystem; R_n and monthly average wind speed (WS) explained 94% variance in monthly ET in the headwater ecosystem. These results indicated that the ET is variable in two alpine wetland ecosystems and R_n was their primary driving factor on monthly scale.

由于具有巨大的节水潜力，高山湿地生态系统在青藏高原的水调节和区域生态安全中发挥着重要作用。各种湿地生态系统的蒸散量（ET）知识对于了解湿地生态系统的水平衡和进行生态环境保护具有重要意义。因此，选择了青海湖流域的湖滨和源头两个高山湿地生态系统，并在两年的时间里研究了它们的ET特征和影响因素。湖边生态系统的日蒸散量呈“双峰”曲线，源头生态系统呈“复峰” ET曲线。在两个各自的湿地中，每月的ET分别为9.88至111.56 mm和0.23至75.5 mm。湖滨生态系统的年ET平均是源头水的1.89倍。逐步多元线性回归表明，每月平均净辐射（R n）和叶面积指数（LAI）解释了湖边生态系统每月ET的96％变化；R _n和月平均风速（WS）解释了源头生态系统中月ET的94％变化。这些结果表明，ET在两个高山湿地生态系统中是可变的，R _n是其每月规模的主要驱动因素。