下垫面的非均匀性影响地气通量观测的准确性和代表性， 青藏高原复杂下垫面通量印痕分布的研究对地气相互作用的观测、 模拟及其天气气候影响均具有重要意义。印痕分析是研究通量观测信息空间代表性的重要方法， 通量印痕模型FFP（Flux Footprint Prediction）为计算通量印痕提供了一种行之有效的方法。基于西藏珠穆朗玛大气过程与环境变化国家野外科学观测研究站、 阿里荒漠环境综合观测研究站、 西藏纳木错高寒湖泊与环境国家野外科学观测研究站、 慕士塔格西风带环境综合观测研究站和藏东南高山环境综合观测研究站5个台站2013年观测数据， 利用FFP模型对通量印痕进行了模型参数敏感性分析， 探讨了不同站点通量印痕分布的时空特点、 具体影响因素， 进而对观测台站架设提供指导。研究结果表明， 通量印痕的主要影响因素为观测高度、 风速、 风向， 下垫面类型为常绿针叶林的林芝站对观测高度、 行星边界层高度较其他台站敏感。在青藏高原， 使用三维超声风速仪观测数据得到的通量印痕的空间尺度为250~500 m。5个台站中珠峰站白天稳定层结时次最少， 占白天数据点的15.69%， 阿里站夜间不稳定层结时次最少， 占夜间数据点的13.32%。在青藏高原5个台站夜间通量印痕比白天通量印痕范围更广、 面积更大； 夏季由于季风的影响， 通量印痕轴线更趋向一致； 纳木错站湖陆风是影响通量印痕的主要因素， 珠峰站冰川风是影响通量印痕的主要因素， 林芝站在5个站点中年平均风速最小， 通量印痕最小， 在5个站点中观测代表性最佳。为提高观测数据代表性， 可考虑在珠峰站、 纳木错站降低观测仪器高度。

The heterogeneity of the underlying surface affects the accuracy and representativeness of the land-atmosphere flux observation.The study on the flux footprint distribution of complex underlying surface over Qinghai-Xizang Plateau （QXP） is of great significance to the observation and simulation of land-atmosphere interaction and its influence on weather and climate.Flux footprint analysis plays a pivotal role in investigating the spatial representativeness of flux observation information.The Flux Footprint Prediction （FFP） model represents a proficient methodology for computing the flux footprint.Based on the observation data from multiple research stations， including the Qomolangma Atmospheric and Environmental Observation and Research Station， the Ngari Desert Observation and Research Station， the Nam Co Monitoring and Research Station for Multisphere Interactions， the Muztagh Ata Westerly Observation and Research Station， the Southeast Tibet Observation and Research Station for the Alpine Environment in 2013， the FFP model was utilized to investigate the sensitivity of model parameters concerning flux footprint distribution.Additionally， the spatiotemporal characteristics and specific influencing factors of flux footprint distribution at different stations were discussed， thereby providing valuable insights for the erection of future observing stations.The results reveal that the primary determinants of flux footprint are measurement height， wind speed and wind direction.Characterized by an underlying surface of evergreen coniferous forest， flux footprint at Linzhi station exhibits greater sensitivity to measurement height and planetary boundary layer depth compared to the other stations.In the QXP， the spatial extent of the flux footprint derived from the ultrasonic anemometer measurements ranges from approximately 250 m to 500 m.Among the five stations， Qomo station exhibited the lowest frequency of stable stratification times during daytime， representing 15.69% of the daytime data points， whereas Ali station had the lowest occurrence of unstable stratification times during nighttime， comprising for 13.32% of the nighttime data points.At these five stations on the TP， the nocturnal flux footprints demonstrate greater width and extent compared to their daytime counterparts.In summer， due to the influence of monsoon， the axis of flux footprint tends to be more consistent.Lake-land breeze at Nam Co station is the main factor affecting flux footprint， whereas glacier wind at Qomo station is the dominant factor.Linzhi station possesses the smallest footprint due to the smallest mean wind speed， thus demonstrating the highest level of representativeness among these five stations.Lowering the height of observation instruments at Qomo and Nam Co stations could potentially enhance the representativeness of in situ measurements.