A proposed model for simulating evapotranspiration of barley in the Qinghai-Tibet Plateau
WANG Kang
JIN Xiaoli
LI Yuqing
ZHOU Zuhao
Abstract：[Objective]Evapotranspiration is a critical component of hydrological cycling and accurately estimating it is essential to improving water resource management in catchments.In this paper,we proposes a new model to stimulate the evapotranspiration of barley in the Tibetan Plateau.[Method]A physically-based model that integrates hydrological process and energy balance into the soil-plant-atmosphere continuum system was developed to simulate evapotranspiration;an experiment was conducted using lysimeters at the Experimental Station of Tibet Agricultural and Animal Husbandry University to measure the evapotranspiration of the barley during its growing season in 2019,2021,2022 and 2024 for model validation.[Result]The Nash-Sutcliffe efficiency coefficient between evapotranspiration measured and simulated using the model was higher than 0.747,with mean and standard deviation errors less than 5%and 10%,respectively.Compared to evapotranspiration calculated using the Penman-Monteith formula,the proposed model improved the Nash-Sutcliffe efficiency coefficient by 88.6%,reduced the relative root mean square error,systematic and total deviations by 25.9%,55.1%and 22.3%respectively.In the study area,both the evapotranspiration of barley and its variability were significantly higher than those estimated by the Penman-Monteith formula.When soil moisture was sufficient to meet the demand of the barley,global sensitivity analysis revealed that the influence of the parameters characterizing climate and energy conversion on the evapotranspiration was significantly greater than that of other driving factors,such as net radiation and flux transmission parameters.The hydrology-energy relationship and energy balance had a substantial influence on the evapotranspiration of barley in the plateau.[Conclusion]The proposed model accurately captured the fundamental mechanisms controlling the evapotranspiration of barley in the Tibetan Plateau,and can be used to simulate spatiotemporal changes in evapotranspiration of other crops in the region.
Keywords：Tibetan Plateauhighland barleyevapotranspirationcoupling of the energy and hydrological processesPenman-Monteith model
Publication Date：2025-12-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 1-8 )