Experimental study on the mechanism of canopy interception using artificial Christmas trees

树冠截留量（降雨时的蒸发量）在室外场地使用放置在托盘上的人造圣诞树（高度为65厘米至240厘米）进行测量。林冠截留与降雨的比值在10%多一点到20%左右，与实际林分相当。间伐减少树冠截留；然而，我们发现了一种情况，即疏林增加了树冠截留。测量了雨中蒸发量、雨停时蒸发量和雨停后蒸发量三个冠层拦截要素，结果表明，雨中蒸发量占冠层拦截量的大部分。研究结果支持了一个假设，即雨滴撞击树冠产生的飞溅液滴会蒸发。

Canopy interception (evaporation at the time of rainfall) was measured at an outdoor site using artificial Christmas trees (65 cm to 240 cm in heights) placed on trays. The ratio of canopy interception to rainfall was within the range of a little more than 10% to some 20% that was comparable to that in actual forest stands. Thinning reduces canopy interception; however, we found a case that thinning increases canopy interception. Three canopy interception elements, evaporation during rainfall, evaporation during storm break time, and evaporation after the cessation of rainfall, were measured, and it turned out that evaporation during rainfall accounted for most part of canopy interception. The results support a hypothesis that splash droplets produced by raindrops hitting canopy evaporate.