中文摘要：

通过对内蒙古阿拉善左旗荒漠下垫面观测数据的分析和模拟,重新修正了陆面过程模式Co LM中的重要参数值和参数化方案,并按照不同的组合方式设计了控制实验和敏感性实验,对比分析重要参数对该下垫面陆气相互作用的敏感性。主要结论有：（1）基于Monin-Obukhov相似性理论的最大频数法,优化了地表动力学粗糙度,重新计算和选择符合研究区域地表热力学粗糙度和土壤热导率的参数化方案;（2）参数优化和参数化方案修正后,提高了Co LM模式对土壤温度,感热通量和地表净辐射的模拟能力;（3）改善前后Co LM模式的模拟值与观测值对比表明,地表动力学与热力学粗糙度和土壤热导率分别在春夏季和秋冬季对地表温度影响较大,感热通量在夏半年主要对地表动力学粗糙度敏感,而土壤热导率对其影响很小。

英文摘要：

To improve the modet, the land-surface key parameter and parameterization schemes in the Common Land Model （CoLM） were calibrated based on the observed data collected in the desert underlying surface in Alxa Left Banner, inner Mongolia in northwest China, and the control and sensitive tests with different combinations of the parameter and parameterization schemes were carried out to analyze the sensitivity in land-atmosphere interac- tion for the modified key parameters over this desert. The main conclusions were summarized as follows：（1） The pa- rameter of the surface aerodynamic roughness length was optimized by the maximum frequency method based on the Monin-Obukhov similarity theory, and the parameterization schemes of the thermal roughness length and soil ther- mal conductivity that performed best were selected to replace the original schemes;（2） The CoLM simulation per- formance of the soil temperature, sensible heat flux and surface net radiation was significantly improved after the parameters were optimized and the parameterization schemes were revised;（3） The comparisons between the simula- ted values of the CoLM model before and after modifying and the observed values suggested that the ground surface temperature was sensitive to the surface aerodynamic roughness length and thermal roughness length in spring and summer, but the soil thermal conductivity affected significantly the ground surface temperature in autumn and win- ter. Simultaneously, the sensible heat flux was much more sensitive to the surface aerodynamic roughness length in summer half year, and less sensitive to the soil thermal conductivity.