大兴安岭低质林不同皆伐改造后枯落物持水性能分析

对大兴安岭地区阔叶低质林、白桦低质林进行不同带宽的带状和不同面积的块状两种皆伐方式改造后枯落物持水性能变化进行研究。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均小于半分解层的枯落物蓄积量;枯落物蓄积量排序:块状皆伐(29.41±7.18)t/hm2>带状皆伐(22.80±5.61)t/hm2>对照样地(18.57±8.46)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均小于半分解层的最大持水量;枯落物最大持水量排序:块状皆伐(109.70±16.92)t/hm2>带状皆伐(92.04±13.97)t/hm2>对照样地(67.25±17.66)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。

Water-Holding Capability of Litter in Low-Quality Forests After Clear Cutting in Great Xing' an Mountains

An experiment was conducted to study the change in water-holding capacity of litter in low-quality mixed forest and Betula platyphylla forest in Great Xing’an Mountains after strip clear cutting with different bandwidth and patch clear cutting with different areas.Results showed that the percentage of the volume of litter in non-decomposed layer was less than that of litter in half-decomposed layer in the forests with bandwidth of 6-18 meters,and the same tendency was also observed in the forests with patch area of 5 m×5 m-30 m×30 m.The volume of litter in the sample plots after patch clear cutting((29.41±7.18)t/hm2) was highest,followed by strip clear cutting plots((22.80±5.61)t/hm2) and the check plot((18.57±8.46)t/hm2).The percentage of the maximum water holding capacity of litter in non-decomposed layer was less than that of litter in half-decomposed layer in the forests after strip clear cutting with different bandwidth,and the same tendency was also found in the forests after patch clear cutting with different areas.The maximum water holding capacity of litter in the forests after patch clear cutting((109.70±16.92)t/hm2) was highest,followed by strip clear cutting plots((92.04±13.97)t/hm2) and the check plot((67.25±17.66)t/hm2).The relationship between water holding capacity of litter and soaking time could be described by logarithmic functions,while the relationship between water absorption rate and soaking time by power functions.