ABSTRACT

Canopy interception (I) can be divided into three processes: evaporation during rainfall (I_R), during storm break time (I_Sbt) and after cessation of rainfall. Those values were measured using plastic Christmas tree stands, and it was found that I_R was much larger than I_Sbt. Although it is commonly accepted that wet canopy evaporation is a major process of I, if so, I_Sbt must be greater than I_R because of higher potential evaporation during storm break time. It was also demonstrated that measured I_R was greater than calculated I_R using the Penman-Monteith (PM) equation that assumes wet surface evaporation. Splash droplet evaporation (SDE), described as splash droplets generated by a raindrop hitting the canopy evaporate, was an alternative mechanism of I. SDE can elucidate I_Sbt « I_R; for a larger rainfall amount, the number of splash droplets becomes higher. Calculated I_R was smaller than measured I_R because the PM equation does not include SDE.

摘要

冠层截留（我）可以分成三个过程：降雨（期间蒸发我_ř期间风暴休息时间（），我_SBT）和降雨停止之后。这些值是使用塑料圣诞树架测量的，发现I _R比I _Sbt大得多。虽然普遍认为湿冠层蒸发是I的主要过程，但如果是这样，I _Sbt必须大于I _R，因为在风暴中断期间更高的潜在蒸发。还证明了测量的I _R大于使用 Penman-Monteith (PM) 方程计算的I _R，该方程假设湿表面蒸发。飞溅液滴蒸发 (SDE)，被描述为由雨滴撞击树冠蒸发产生的飞溅液滴，是I的另一种机制。SDE 可以阐明I _Sbt « I _R ; 雨量越大，飞溅的水滴数量越多。计算的I _R小于测量的I _R，因为 PM 方程不包括 SDE。