河北省木兰林管局典型森林类型枯落物水文效应研究

Hydrological Effects of Typical Forest Litters in the Mulan Forestry Administration of Hebei Province

枯落物层作为森林水文效应的第二个活动层,在调节森林水文过程中具有重要的意义。对木兰林管局6种典型天然林分枯落物层的水文效应进行了初步研究,结果表明:(1)华北落叶松-白桦-黑桦混交林枯落物总蓄积量最大为30.47 t/hm2,最大持水量最高为63.57 t/hm2;白桦-黑桦混交林枯落物最大持水率最大为257.80%。(2)未分解层和半分解层枯落物浸泡12 h均已基本达到饱和,持水量与浸泡时间呈明显对数关系;枯落物吸水速度在开始1 h内较快,6 h后速度逐渐减慢,吸水速率与浸泡时间均呈明显幂函数关系。(3)华北落叶松-白桦-黑桦混交林的有效拦蓄能力最强,为48.60 t/hm2;山杨-黑桦-蒙古栎混交林的有效拦蓄能力最弱,为16.47 t/hm2。即华北落叶松-白桦-黑桦混交林枯落物的水土保持能力最强,森林较健康,山杨-黑桦-蒙古栎混交林最弱,健康状况有待改善。

Litter is the second active layer of the forest hydrological effects,which is of great significance in the regulation of forest hydrology.A preliminary study of hydrological effects of litter layer was carried out in six kinds of typical and natural forest stands in the Mulan forestry administration.The result shows：（1）The litter total storage capacity of Larix principic-rupprechtii-B.platyphylla-B.davurica is the biggest and up to 30.47 t/hm2,meanwhile it has the highest maximum water holding capacity（63.57 t/hm2）;the maximum water holding rate of B.platyphylla-B.davurica is the biggest and up to 257.80%;（2）Without decomposition and semi-decomposition litter reached both saturation in 12 h,water holding capacity and soaking time demonstrated significant Logarithmic relationship（Q=aln（t）＋b）;water absorption rate of undecomposed and semi-decomposed litter are both faster at the first hour,then the rate of decline gradually slowed down after 6 h,the relationship of absorption rate and immersion time showed power function（V=ktn）;（3）The modified interception amount of Larix principic-rupprechtii-B.platyphylla-B.davurica is the strongest and up to 48.60 t/hm2,while Populus davidian-B.davurica-Quercus mongolica is the worst and up to 16.47 t/hm2.It shows that the soil and water conservation capacity of Larix principic-rupprechtii-B.platyphylla-B.davurica is the strongest,which means the forest is healthy.However,Populus davidian-B.davurica-Quercus mongolica has the weakest capacity,which means the health need to be improved.