Evapotranspiration Change Under Short-Term Experimental Warming In A Swamp Meadow Ecosystem Of The Qinghai-Tibet Plateau

The impact of climate change on the cold region ecosystem is deepening, especially in the Qinghai-Tibet plateau(QTP), with its impacts on the water cycle. Evapotranspiration (ET), as an important part of the hydrological cycle in terrestrial ecosystems. Thus, we analyzed the influence of experimental warming on ET through observed data of 2008 under two open top chambers (OTC-1 and OTC-2) plots and ambient air (Control) plot. The study showed that the potential and actual ET of OTCs were higher than that of Control, due to increase in vapor pressure deficit, warmer air temperature, increase in ground surface soil moisture and temperature compared to the outside. ET is largest component of water loss from alpine ecosystem, accounted for 74.6% of the annual total precipitation. Elevated CO2 concentration had no significantly affected at ET rate in our study. The results will be helpful for future climate change study in the QTP.