中文摘要：

利用2009年夏季敦煌地区加强期观测资料，分析了稀疏植被下垫面C02、水汽的通量输送规律和地表辐射、能量平衡等微气象的变化特征。结果表明，敦煌地区夏季C02、水汽通量有明显的日变化，其平均通量分别为-0．023mg·m^-2·s^-1和2．90mg·m^-2·s^-1；地表平均反照率为0．24，低于绿洲内部；感热是该地区地表热量流失的主要形式，潜热和土壤热通量相对较小，平均波文比为3．08；观测中也发现了有较大的能量不平衡现象，利用试验资料估算了土壤容积热容量，并在能量平衡方程中加入了土壤热储量，提高了能量平衡度。

英文摘要：

Utilizing the micrometeorology data of the intensive observation period in Dunhuang oasis in the Northwest arid region in 2009, the air exchanges and energy budget are systemically analyzed, such as the and water vapor flux and CO2 concentration, radiation budget, and energy balance. The result shows that： The and water vapor flux and CO2 concentration have obvious diurnal variation and the mean value are -0. 023, 2.90 mg. m a . s 1, respectively the sensible heat, latent heat and soil heat have good cor- relation with the net radiation, and the mean ground surface albedo is 0.24 The sensible heat is the main factor of surface energy loss and the average value of Bowen ratio is 3.08, and there is a larger energy im balance in the observation.