不同采伐强度改造对小兴安岭低质林土壤理化性质的影响

Impact of Different Cutting Intensities on Soil Physical and Chemical Properties of Low-Quality Forest Stands in Xiaoxing'an Mountains After Reconstruction

对小兴安岭低质林进行不同采伐强度的改造,分析不同采伐强度改造后土壤理化性质的动态变化。结果表明:采伐强度在22%～77%范围内,①样地Z1(22%)、Z2(31%)、Z6(66%)、Z7(77%)在伐后前3 a的物理性质优于样地Z3(41%)、Z4(47%)、Z5(55%);②样地Z4、Z5在伐后前3 a的化学性质较好;③随着改造时间的推移,土壤的物理性质在不断改善;④各样地的土壤化学性质在改造后前3a变化明显,改造后第一年土壤养分上升,随后下降;⑤土壤有效养分高于对照样地;⑥土壤理化性质在趋于改善。

A study was conducted to analyze the dynamic change in soil physical and chemical properties of low-quality forest stands in Xiaoxing＇ an Mountains after the reconstruction of different cutting intensities. Results show that, within the cutting intertsity ranging from 22% to 77%, the soil physical properties of sample plots Z1（22 % ）, Z2（31% ）, Z6（66% ） and Z7（77% ） were better than those of sample plots Z3（41% ） , Z4（47% ） and Z5（55% ） in the first three years after reconstruction ; while the soil chemical properties of sample plots Z4 and Z5 were better. The soil physical properties of the sample plots were gradually ameliorated with prolonging reconstruction time. The soil chemical properties of the sample plots changed obviously in the first three years after reconstruction, and soil nutrients increased in the first year after reconstruetion, and then declined. Soil available nutrients in the sample plots were higher than those in the unthinned stand. Soil physical and chemical properties tended to improve after reconstruction.