黄土丘陵区人工油松林和山杨林林冠截留作用的研究

本文研究了25年林龄的油松人工林和天然山杨林的林冠截留量及其变化。结果表明:油松人工林和山杨林林冠年截留量分别为95.2mm和73.4mm,占年降水量的19.6%和14.7%。其中对降雨的截留量分别为78.0mm和71.1mm,分别占降雨量的17.4%和15.5%;对降雪的截留量为17.2mm和2.3mm,分别占降雪量的45.1%和5.9%。林冠截留量也有季节变化,两林分夏季截留量51mm,占同期降水量的15.8%。油松林冬季截留量较小,但占同期降水量的比例高,山杨林两者均小。林冠截留过程分为截留、透过、饱和三个阶段,其累积截留量与累积降水量呈I=apb函数关系。

A Preliminary Study on Interceptive Function of the Canopy of Pinus tabulaeformis and Populus davidiana Stands in the hiyg Areas on the Loess Plateau

The intercepted precipitation and its variation of the canopy of Pinus tabulaeformis and Populus davidiana of 25 years old have been studied.The conclusion shows that the intercepted precipitation of Pinus tabulae-formis and Popular davidiana are 95,2mm and 73.4mm,accounting for 19.6and 14.700 of yearty total ramfall respectively; Intercepted rainfall is78mm and 71.lmm, accounting for 17.40o and 15,500 of rainfall; Intercepted snow is 17.2mm and 2,3mm,accounting for 45.1%and 5.900 of snowfall.The intercepted amount of the canopy changes with different seasons,In summer, the intercepted amount is 51mm,15.8} of the annual rainfall.In spring and winter,Pinus tabulaeformis intercepted amount is low, and intercepted rate is high, Also, both of them in Populus davidians are low, The interceptive process of the canopy is divided into three stages as intercepting,falling raindrop and saturating,The function between the accumulated interceptation and precipitation presents I=ap^b.