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为了改善陆面过程模式在半干旱地区的模拟能力,在SHAW（Simultaneous Heat and Water Model）模式和CoLM（Common Land Surface Model）模式参数化方案基础上,结合黄土高原SACOL站（Semi-Arid Climate and Environment Observatory of Lanzhou University）得到的部分土壤和近地层的研究结果,利用SHAW模式的动力框架,发展了一个新的陆面过程模式TBLSHAW（Two-Big-Leaf-SHAW）。该模式由一层植被、多层土壤和湍流边界层构成。在植被层主要采取双大叶模型计算能量平衡;土壤层利用水热耦合传输模型计算土壤温度和湿度,并包含了冻融、蒸发及降水渗透等物理过程;湍流边界层采取莫宁—奥布霍夫理论计算湍流通量。最后利用SACOL站获取的观测资料,对TBLSHAW模式进行了模拟检验。结果表明,TBLSHAW模式能够合理地模拟半干旱地区各项陆面过程特征的变化趋势;模拟的土壤温度和土壤湿度与观测值的偏差较小,模式效率和相关系数较高;模拟的净短波辐射及向上长波辐射较好;但是模拟的感热通量、潜热通量与观测值偏差较大,这可能与该地区的能量闭合度较低有关,还有待进一步研究。“,”In order to improve the land surface model simulation in the semi-arid region,a new land surface model TBLSHAW(Two-Big-Leaf-SHAW) is developed based on the parameters of SHAW(Simultaneous Heat and Water Model) and CoLM(Common Land Surface Model) Model,and use the soil and near-surface boundary results obtained by SACOL(Semi-Arid Climate and Environment Observatory of Lanzhou University) site on Loess Plateau.The model includes a vegetation layer,several soil layers,and turbulent boundary layer.The vegetation layer use the two-big leaf model to calculate energy balance;soil layers used a coupled heat and moisture transport model to calculate soil temperature and soil moisture,and include the physical process such as the soil freezing and thawing,evaporation and precipitation infiltrate;turbulent boundary layer took use of the Monin-Obukhov theory to calculate turbulent heat fluxes.At last,the data which is obtained by SACOL site are used to evaluate the TBLSHAW model.The simulated result indicate that the model can well simulate all the change tendency of the land surface characteristics at semi-arid region;the bias of the simulated soil temperature and moisture are small with the observed values,model efficiency and correlation coefficient are high;the model can well simulate net shortwave radiation and upward longwave radiation,but the bias of the simulated sensible and latent heat fluxes are large,that may be attributed to the low energy closure in this region,and need to investigate in the future.