荒漠草原不同时间尺度下垫面水分消耗与气象植被因子的关系

利用大型称重式蒸渗仪2012—2018年连续观测数据，系统解析了希拉穆仁荒漠草原植物生长季（4—10月）不同时间尺度蒸散发（ET)与气象植被因子之间的关系。研究表明：（1）小时、日和月尺度上，始终与ET保持高度相关的气象植被因子包括风速（P<0.01）、空气温度（P<0.01）和降水量（P<0.01）；（2）结合不同时间尺度主控因子，利用多元回归定量表征了小时、日、月尺度的下垫面ET变化特征，经验方程决定系数分别为0.94（P<0.01）、0.42（P<0.01）、0.82（P<0.01），小时和月尺度上的经验方程可较好地反映希拉穆仁荒漠草原下垫面耗水特征；（3）ET与降水差值显示，2012—2018年希拉穆仁荒漠草原植物生长季（4—10月）水汽交换以下垫面水分消耗为主，8月份发生干旱事件的概率最大。

Relationship between water consumption and meteorology\|vegetation parameters in the desert grassland on different time scales

Data from a large\|scale weighing lysimeter was used to systematically analyze the relationship between the evapotranspiration and meteorology\|vegetation parameters on different time scales during the Xilamuren desert grassland plant growth season from 2012 to 2018. (1) Wind speed (P<0.01), air temperature (P<0.01), and precipitation (P<0.01) were significantly correlated with the evapotranspiration on the different time scales. (2)Empirical equations for hourly, daily, and monthly time scales were established based on the multivariate regression analysis with coefficients of determination of 0.94 (P< 0.01), 0.42 (P<0.01), and 0.82 (P<0.01)., respectively. The empirical equation accurately simulated the water consumption characteristics of the underlying surface of the Xilamuren desert grassland on the hourly and monthly scales.(3) According to the difference between ET and precipitation from April to October, water vapor exchange during the plant growth season was mainly characterized by water consumption on the land surface from 2012 to 2018. The probability of drought occurred the most in August every year. These results are useful for studying water vapor exchange and monitoring drought in the desert grassland.