摘要
本文研究了人工油松(Pins tablaeformis)林和天然山杨(Populus davidiana)林林内降雨雨滴直径分布规律和降雨动能。结果表明,林内雨滴径级变幅增大,粗大雨滴偏多;林内雨滴终速取决于林冠层中部距地面高度,当高在8.0m以上,可以用空旷地雨滴终点速度计算林内雨滴动能;林内降雨动能较空旷地大,所增加的动能主要是雨滴增大的结果;林内降雨动能(E)与平均雨强、降雨量、降雨历时呈二次多项式关系。
The diameter distribution and kinetic energy of raindrop in stands of P. tabulaeformis and P. davidiana have beed studied in the paper. The results showed that the influction range of diameter classes of raindrop increases and there are more big raindrops in size in the stands. The terminal velocity of raindrop in stands depends on the height from the middle part of canopy to the ground. When the height is more than 8m, The kinetic energy in stands is larger than in open field by reason of increased size of raindrop. The relationships between the kinetic energy of raindrop in stand (E) and average rain intensity(Ⅰ), precipitation(p) and a period of rain time(t) may be expressed by quadratic multinomial.
基金
国家自然科学基金
关键词
油松
山杨
降雨动能
Pinus tabulaeformis Populus davidiana kinetic energy of raindrop
