蒸发测定方法*

土壤一植物一大气系统,实际上可以看成为地球表层中的一个界而。它是一个多种物理、化学和生物过程变化和能量物质迁移运动最为剧烈的活动层。在这一系统中水的运动和循环过程又尤为活跃。在水循环的几个环节中,蒸发占着特别重要的地位。热量的释放和吸收是什随着蒸发过程同时进行的。于是蒸发A把物质守恒方程和热量平衡方程两者联系起来。同时,蒸发又是植物生命节奏中的重耍环节,它与植物生理活动和生物产量有密切关系。因此,自然蒸发的研究始终是地理学、气象学、植物牛理生态学、水文学、土壤学和农学等许多学科共同关心的课题。

ON METHODS FOR DETERMINING EVAPOTRANSPIRATION

This paper presents an integrated overview of measurement and computing methods for estimating evapotranspiration from commnnities ranging from agricultural to forested lands. Discussion is presented on how to select an appropriate method (or mothods) for a given objective under a given set of conditions.The relevance and accuracy of a particular method depends critically on the circumstances under which it used.Attention is also focused on the important aspects on which information is lacking, and areas where research should be directed in the future.