由于不同区域蒸散发对气候变化的敏感性各不相同，为摸清多年冻土活动层陆面过程中冻土-气候变化-水文循环之间的相互关系，选择青藏高原风火山区域的典型多年冻土区，依据气象站观测资料，应用Penman-Monteith公式计算了典型多年冻土区土壤蒸散发和蒸散发气候敏感系数，分析了多年冻土区土壤蒸散发对气候变化的敏感性。结果表明：多年冻土区土壤蒸散量对相对湿度的敏感性最高（-1.291），其次为风速（0.658），对空气温度的敏感性最低（0.248）；土壤完全融化的植被生长期，蒸散发对各气象因子的敏感性最高，土壤完全冻结的植被枯萎期，蒸散发对各气象因子的敏感性都最低；年内尺度，蒸散发对气温、相对湿度和风速的敏感性均在8月最高，在1月或12月最低；蒸散发对气温和相对湿度的敏感性变化与植物生长变化过程高度一致，而蒸散发对风速的敏感性则较为复杂，与土壤的冻融过程相关，分别在土壤逐渐融化的植物生长前期和土壤完全融化的植物生长期敏感性较高。
The sensitivity of evapotranspiration to climate change, which varies in different regions, may lay a foundation for understanding the relationship between permafrost, climate change and hydrological cycle during permafrost activity. This paper calculated the soil evapotranspiration amount and its climatic sensitivity coefficient by Penman-Monteith equation based on the observation data of meteorological stations and analyzed the soil evapotranspiration in typical permafrost regions of the Qinghai-Tibetan Plateau. The results show that soil evapotranspiration is most sensitive to relative humidity (-1.291), followed by wind speed (0.658), and lowest was air temperature (0.248). The sensitivity of soil evapotranspiration to climate was highest in vegetation growth period while lowest in vegetation withering period. The sensitivity of soil evapotranspiration to climate change reached the highest value in August and the lowest value in January or December. The sensitivity of soil evapotranspiration to air temperature and relative humidity varied with the change in vegetation growth. But the change in the sensitivity of soil evapotranspiration to wind velocity was complex and related with transformation in soil freezes and melts.
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