滦河上游水源涵养林枯落物层水文效应研究

On the hydrological effects of litter layer of Luan River water conservation forest

为探讨森林枯落物水文过程及规律,对滦河上游3种不同类型林分枯落物及其结构进行了调查,并对其水文效应进行了探讨。结果表明:1油松纯林的枯落物生物量为12.03t/hm2,最大持水量为19.4t/hm2,有效拦蓄量为23.52t/hm2;落叶松纯林的枯落物生物量为9.51t/hm2,最大持水量为11.9t/hm2,有效拦蓄量为17.03t/hm2;落叶松白桦混交林的枯落物生物量为5.54t/hm2,最大持水量为13.0t/hm2,有效拦蓄量为13.7t/hm2。2半分解层枯落物浸泡8h已基本达到饱和,而未分解层需浸泡10h,持水量与浸泡时间的关系式为Q=alnt+b;枯落物在浸水的前0.5h内吸水速率最大,4h左右时吸水速率明显减缓。

Based on 3 different types of forest litter layer in the upper reache of the Luanhe River ,the undecomposed and semidecomposed layers as well as the hydrological effect ,were investigated .The results showed：① The litter accumulation amount of Pinus tabulaeformis forest was 12 .03 t/hm2 ,with the maximum water holding capacity of 19 .4 t/hm2 and effec‐tive retaining content of 23 .52 t/hm2 .Larch forest litter biomass was 9 .51 t/hm2 ,and its maximum water holding capacity was 11 .9 t/hm2 ,with its effective retaining content of 17 .03 t/hm2 .The litter biomass of mixed forest of larch and birch was 5 .54 t/hm2 ,with the maximum water holding capacity of 13 .0 t/hm2 and effective retaining content of 13 .7 t/hm2 . ② The semidecomposed litter bsically reached saturation when ,immersed in 8 h while the decomposed litter needed to be soaked for 10 h to reach its saturation .Through the analysis of the relationship between water holding capacity and the soaking time ,the Q= aln t＋ b was got ,with the maximum water absorption rate of litter immersed in 0 .5 h ,and obvi‐ous reduction in about 4 h .