Abstract: Zhalong Wetland was selected as a case study region.The Surface Energy Balance Algorithm for Land(SEBAL) model combined with Landsat-7 ETM+ image,DEM and meteorological data of 12 stations near Zhalong wetland were used to inverse land surface fluxes,such as net radiation,soil heat flux and sensible heat flux.Then the latent heat flux was calculated through energy balance equation and the daily evapotranspiration was estimated.The spatial distribution characteristic of daily evapotranspiration was analyzed by referencing land-use map of 2001.It was found that the water body and marshland were at high evapotranspiration rate,while the paddy field,grassland and woodland took the second place,and the dry land,unused land and residential area were at lowest evapotranspiration rate,which were accorded with the evapotranspiration theory.The result showed that SEBAL model had considerable practicability in estimating regional evapotranspiration.

Key words: Evapotranspiration, Evapotranspiration, Energy balance, Surface Energy Balance Algorithm for Land(SEBAL) model, Zhalong Wetland, ETM+ image