大兴安岭白桦低质林皆伐改造后枯落物水文效应

Hydrological Effect of Birch Coppice Low-Quality Forest Litter after Clear-cutting Transformation in Daxing'an Mountains

对大兴安岭地区白桦低质林进行不同带宽的带状和不同面积的块状两种不同皆伐方式的改造后枯落物水文效应变化的研究。结果表明:带宽为6~18 m的皆伐带未分解层枯落物蓄积量所占比例均小于半分解层的枯落物蓄积量,面积为5 m×5 m^30 m×30 m的块状区域未分解层枯落物蓄积量所占比例和半分解层比较大小不一;枯落物蓄积量排序:带状皆伐8.67 t/hm2>块状皆伐4.41 t/hm2。每条带宽的皆伐带未分解层的最大持水量所占比例均小于半分解层的最大持水量,每个面积的块状区域未分解层的最大持水量所占比例和半分解层比较大小不一;枯落物最大持水量排序:块状皆伐35.44 t/hm2>带状皆伐14.23 t/hm2。每条皆伐带未分解层枯落物有效拦蓄量所占比例均小于半分解层的枯落物有效拦蓄量,每个面积的块状区域未分解层的有效拦蓄量所占比例和半分解层比较大小不一;枯落物有效拦蓄量排序:带状皆伐25.17 t/hm2>块状皆伐7.81 t/hm2。带状和块状皆伐方式下,枯落物持水量与浸泡时间的关系均呈现对数关系上升,而枯落物吸水速率与浸泡时间的关系均呈现乘幂关系下降。

The experiment was conducted to study the hydrological ettect ot talhng object in Daxing＂ an Mountains ot torch cop pice low-quality forest in different bandwidth and different area by two different clear cuttings. The litter proportion volume in not decomposition level is less than that of the half decomposition level in bandwidth for 6 m-18 m clear cutting band. While litter proportion volume in no decomposition level has no significant relationship with the half decomposition level in the area of 5 mx5 m-30 mx30 m. The volume of litter shows band clear cutting 8.67 t/hm2 〉 area clear cutting 4.41 t/ hm2. Water holding capacity in no decomposition layers of the largest proportion is less than that in half decomposition lay ers in each bandwidth, while water holding capacity in no decomposition layers of the largest proportion has no significant relationship with that in half decomposition layers in each area. Maximum litter moisture capacity shows area clear cutting 35.44 t/hm2 〉band clear cutting 14.23 t/hm2. The largest proportion of effective held in no decomposition layers is less than that in half decomposition layers in each bandwidth, while the largest proportion of water holding capacity in no de composition layers has no significant relationship with effective held in half decomposition layers in each area. Litter effective held shows band clear cutting 25.17 t/hm2 〉area clear cutting 7.81 t/hm2. Litter water holding capacity and soaking time are significantly increased with logarithmic relationship, while litter bibulous rate and soaking time are significantly decreased with power relationship.