冀北山地油松和落叶松林下枯落物的水文效应

对河北省木兰围场国有林场内油松、落叶松人工林枯落物水文效应进行了调查。结果显示,油松、落叶松枯落物厚度分别为6.1和4.0cm,枯落物蓄积量为33.93和43.16t/hm2;浸泡24h后测定油松枯落物的含水量为268.10g,落叶松枯落物含水量为157.54g,二者的有效拦蓄量分别为30.07和57.56t/hm2。油松、落叶松林下枯落物持水量、吸水速率与浸水时间的变化规律基本一致,枯落物持水量与浸水时间存在对数曲线关系,而吸水速率与浸泡时间存在幂函数关系;枯落物浸水0～4h内吸水速率最大,4～8h内逐渐变缓,10h后其持水量基本达到最大值。

Hydrological Effects of Pinus Tabulae f ormis and Larix Princpis Forest Litters in North Mountain of Hebei Province

This study investigated water-holding characteristics of Pinus tabulaeformis and Larix princpis forest litter found in Mulan—Weichang National forest farm.The results show that in the Pinus tabulaeformis and Larix princpis forests,the litter was as thick as 6.1and 4.0cm,with total water holding capacity of 33.93and 43.16t/hm2,absorbed water contents of 268.10g and 157.54g(measured after 24himmersion),and effective interception capacity of 30.07and 57.56t/hm2,respectively.The litters of Pinus tabulaeformis and Larix princpis showed similar water-holding capacity,water absorption rate and soaking time.Overall,the relationship between litter water-holding capacity and soaking time was described well with a logarithmic curve,and that between the water absorption rate and soaking time was fitted well with a power function.The water absorption rate was fastest in the initial 0～4h,decreased gradually in 4～8hafter immersion,and the water content reached its maximum water-holding capacity after 10h.