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林业科学 ›› 2011, Vol. 47 ›› Issue (2): 15-24.doi: 10.11707/j.1001-7488.20110203

• 论文 • 上一篇    下一篇

择伐对天然云冷杉林林分生长和结构的影响

胡云云1,2, 闵志强1, 高延3, 冯启祥3   

  1. 1. 北京林业大学省部共建森林培育与保护教育部重点实验室 北京 100083;2. 国家林业局西北林业调查规划设计院 西安 710048;3. 吉林省汪清林业局 汪清 133200
  • 收稿日期:2010-01-29 修回日期:2010-12-26 出版日期:2011-02-25 发布日期:2011-02-25

Effects of Selective Cutting on Stand Growth and Structure for Natural Mixed Spruce (Picea koraiensis )-Fir (Abies nephrolepis) Forests

Hu Yunyun1,2, Min Zhiqiang1, Gao Yan3, Feng Qixiang3   

  1. 1. Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University Beijing 100083;2. The Northwest Institute of Forest Inventory, Planning and Design, SFA Xi'an 710048;3. Wangqing Forestry Bureau,Jilin Province Wangqing 133200
  • Received:2010-01-29 Revised:2010-12-26 Online:2011-02-25 Published:2011-02-25

摘要:

以20块经过抚育的天然云冷杉林样地为研究对象,分析第2次择伐前不同初始择伐强度(对照、20%、30%和40%)对林分生长和结构的影响,以及初始择伐后不同恢复时间(期间进行2~4次择伐)林分生长和结构的变化。结果表明:初始择伐后的样地林分平均胸径和蓄积的年生长率相对高于对照样地,采伐后开始增加,4~6年后减小直至下次采伐;初始择伐后6年20%强度的林分蓄积年生长率与30%和40%差异不大,但40%强度择伐后的林分平均胸径年生长率显著增加;30%强度以上择伐后的林分生长相对较快,胸径和蓄积年生长率最高分别达2.6%和8.7%;经过合理的2~4次择伐的林分平均胸径和蓄积的年生长率相对高于仅1次择伐和未择伐的林分,2009年最大值分别为3.6%和5.5%;随着初始择伐后时间的增加,各样地林分径级分布由初始的反"J"型向不对称的单峰或多峰山状曲线变化;但经2~4次择伐的样地,只要控制合理的采伐周期(6年左右)和强度(20%左右),就能保持较好的径级结构;通过负指数分布拟合发现,各样地的K值和a值随着伐后时间延长基本呈减小趋势。

关键词: 天然云冷杉林, 择伐, 胸径, 蓄积, 径级结构, 负指数分布

Abstract:

Twenty plots in natural spruce-fir forests, after initial selective cutting with different intensity (control, 20%, 30%, 40%), were set to study effects of the different cuttings on stand growth and structure in a few year when the second cutting was conducted, and changes of stand growth and structure in different recovery periods with 2-4 more cuttings after the initial cutting were analyzed in this paper. Results showed that the annual growth rates of stand DBH and volume after the initial selective cutting were higher than that of un-cutting control stands. After the initial cutting they gradually increased, and then the rates began to decline in 4-6 years, until to the next cutting. The annual growth rate of stand volume in the plots with the initial cutting of 20 % was not significantly different from the plots with cutting intensities of 30 % and 40 % in 6 years, but the annual growth rate of DBH in plots with the cutting intensity of 40 % increased significantly. The annual growth rates of stand DBH and volume in plots with the cutting intensity above 30 % were relative high with maximum value of 2.6 % and 8.7 % respectively. The annual growth rates of stand DBH and volume were higher in plots carried out with 2-4 reasonable cuttings than that of plots with only one cutting or no cutting, and the annual growth rates of stand DBH and volume in 2009 reached to a maximum value of 3.6 % and 5.5 % respectively. The stand diameter class distribution in all the plots with the initial cutting changed from inverse J-shaped to asymmetric single or multi peak curve over the time. With reasonable cutting cycles (in about 8 years) and intensity (about 20 %), stands after 2-4 cuttings could keep a better diameter class structure. By fitted to a negative exponential model, the values of parameter K and a for all plots mainly presented a reduction trend over the time after selective cutting.

Key words: natural mixed spruce-fir forests, selective cutting, DBH, volume, diameter class structure, negative exponential model

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