半干旱地区蒸发互补关系
Analysis of Evaporation Complementary Relationship in Semi-Arid Areas

利用榆中县2006~2009年净辐射、潜热通量、平均风速、平均温度、平均相对湿度资料研究气象因子对实际蒸散量、可能蒸散量和湿润环境蒸散量的影响并利用相对实际蒸散量与相对可能蒸散量建立起实际蒸散量的估算模型。研究发现，在日变化过程中，实际蒸散量、可能蒸散量以及湿润环境蒸散量呈现出先升高、后下降的日变化特征。对实际蒸散量有重要影响的气象因子是近地层温度，呈现负相关关系，湿润环境蒸散量主要的影响因素是地面净辐射这一气象因子，呈现出正相关关系。进一步建立起实际蒸散量的估算模型(A = 0.834, B = ？0.664)，并通过检验证明该模型具有实际可用性。
Using the net radiation, latent heat flux, average wind speed, average temperature and average relative humidity data of Yuzhong County from 2006 to 2009, the effects of meteorological factors on actual evapotranspiration, possible evapotranspiration and wet evapotranspiration were stu-died and the relative actual evapotranspiration was used. An estimated model of the actual eva-potranspiration is established relative to the possible evapotranspiration. The study found that in the course of daily changes, the actual evapotranspiration, possible evapotranspiration, and eva-potranspiration in the humid environment showed a trend of increasing first and then decreasing. There is an important influence on the actual evapotranspiration. The meteorological factor is the near-surface temperature, showing a negative correlation. The main influencing factor of the evapotranspiration in the humid environment is the meteorological factor of ground net radiation, showing a positive correlation. An estimation model of the actual evapotranspiration (A = 0.834, B = ？0.664) was further established, and the model was proved to have practical availability.