【作者】 全昌明；

【导师】 罗菊春；

【作者基本信息】 北京林业大学 ， 生态学， 2004， 硕士

【摘要】 本文在分析内蒙古白音敖包草原区华北落叶松人工林和白桦次生林的群落结构的基础上，对己采取的经营措施进行效果评价，并在此基础上对森林区和草原区的两种林分的生产力进行了分析比较。 结果表明：内蒙古白音敖包草原区华北落叶松人工林胸径、树高连年生长量与年均气温、无霜期关系最密切，其次为年降水量；影响胸径连年生长的关联度最大的因子是无霜期，而影响树高连年生长的关联度最大的因子是年均气温和年降水量。 动物在萌芽和幼苗期间最大的积极作用是破坏了林内很厚的枯枝落叶层，露出了表层土壤，使幼苗根系可以接触土壤。 此地区华北落叶松人工林抚育间伐的起始年龄为12～14年之间，在首次抚育间伐后5～10年之间可进行第二次抚育间伐。并对现实林分进行模拟，取得了较好的效果。 华北落叶松人工林幼龄林采用弱度间伐的效果比较好，而对未经过抚育间伐的中龄林，首次抚育间伐强度可稍大，株数伐强可控制在50～55％。 内蒙古白音敖包草原区的白桦林划分为灌木白桦林、草本白桦林和溪旁白桦林3个群丛，对该地区白桦次生林的经营目标主要是防止逆行演替的发生。经研究，全面抚育改造的方式可以达到这个目的。 坝下森林区和白音敖包草原区的自然地理因子存在着较大的差异，本文仅从生产力的角度对其进行了探讨，森林区的华北落叶松人工林和白桦次生林生产力均比草原区中的高。更多还原

【Abstract】 Based on the community structure analysis of the Larix principis-rupprechtii artificial forest and the Betula platyphylla secondary forest, this thesis evaluated the underway tending felling and improvement of second-growth-stand, then compared their productivity in mountain region and steppe region.In Baiyin’aobao area, breast-height-diameter and height annual increment had notable relation with annual mean temperature and frost-free season.Animal could promote Larix principis-rupprechtii artificial forest natural regeneration through destroying layer Ao of soil, so as to the seedling’s roots could grow on the soil.In this area, the first thinning should be carried out during the age of 12a to 14a, and the thinning interval is 5 a to 10a.In the artificial forest, weak thinning should better be applied to the young-age forest, however, in the standard-age forest which was never tending, a strong thinning must carry through in time.The Form. Betula Platyphylla could be classified to Ass. Shrub-Betula Platyphylla, Ass. grass-herb- Betula Platyphylla and Ass. Picea mongolica along streamlet. Full-scale tending improvement could observably avoid recessive succession which was frequently occurred in the frail area.The productivity of Larix principis-rupprechtii artificial forest and Betula platyphylla secondary forest in the mountain region were apparently more higher than that in the steppe region.更多还原