Estimation of farmland evapotranspiration based on SEBAL model in Kai-Kong River Basin, Xinjiang

作     者：Cha Mingxing Wang Xiaoqin Li Yali Qiu Pengxun 

作者机构：Key Laboratory of Spatial Data Mining and Information Sharing of Ministry of Education National & Local Joint Engineering Research Centre of Satellite Geospatial Information Technology Fuzhou University the Academy of Digital China (Fujian) Fuzhou 350108 China. 

出 版 物：《IOP Conference Series: Earth and Environmental Science》 

年 卷 期：2020年第502卷第1期

摘      要：Evapotranspiration (ET) is an important reference for scientific management of farmland irrigation, accurate estimation of crop yields, and optimal allocation of water resources. The purpose of this paper is to estimate ET by taking the farmland of Kai-Kong River Basin in Xinjiang province as an example. The method was based on the SEBAL model and the Landsat data; it estimated the net radiation flux, soil heat flux using the land-surface parameters first, and the instantaneous evapotranspiration was then calculated using the energy residual method and the latent heat flux. The sinusoidal function method was used to extend the time scale of the instantaneous evapotranspiration to the daily evapotranspiration and the daily evapotranspiration were verified using the FAO56 Penman-Monteith formula. The compared results shown that the error of daily evapotranspiration between SEBAL and FAO56 Penman-Monteith is within 1mm, and except for the estimation accuracy of final growth stage is about 80%, the estimation accuracy of other growth stages are more than 80%. The SEBAL model, coupled with the Landsat remote sensing data, can offer an efficient and adequate alternative to estimate ET at catchment scale.