油松栓皮栎混交林降雨及其再分配过程研究

2001年4—10月，通过林内标准地观测，对北京西山地区1块31年生的油松栓皮栎 混交林的降雨及其再分配过程进行观测研究. 结果表明，在试验条件下，降水主要分布在树木的生长季节，尤其集中在6—8月3个月份，占全年降水量的80%以上；各次降雨在油松栓皮栎混交林内的运动过程均是不完全运动形式，降雨量与干流和透流均呈线性关系，当降雨量大于1.43 mm时，试验林分可发生干流，当降雨量大于0.4 mm时，发生透流；整个试验期间，降雨的第1次分配中3个分量占降雨量比例的顺序关系分别为透流量358.15 mm(69.84%)林冠截流量138.05 mm(26.92%)干流量16.60(3.24%). 在第2次分配中，土壤总入渗量（223.08 mm）枯落物的总截持量（149.94 mm）地表径流总量(1.73 mm). 

Rainfall and its redistribution of Pinus tabulaeformis and Quercus variabilis mixed forests.

From April to October of 2001,a mixed stand of Pinus tabulaeformis and Quercus variabilis which was 31 years old was observed to study rainfall and its redistribution through test plot in western mountain area of Beijing.The results showed that the rainfall mainly distributed in the growth season of trees,especially from June to August,which accounted above 80% of the total rainfall.The movement forms of every rainfall were all incomplete and the relation between rainfall and trunk flow and penetration flow was linear.When the rainfall was more than 1.43 mm,the stem flow appeared and when it was more than 0.4 mm,the penetration flow appeared.During experiment,the ratio compositor of three hefts in first distribution was: penetration flow(358.15 mm,69.84% of total rainfall)>forest crown interception flow(138.05 mm,26.92% of total rainfall)>stem flow(16.60 mm,3.24% of total rainfall).In second distribution,the ratio compositor of three hefts was: the soil infiltration(223.08 mm)>dead wood and leaf interception(149.94 mm)>the earth's surface flow(1.73 mm).