Application of Natural Restoration Systems of Canopy Gap to Improvement of Coppice Stand

集约利用的矮林林分林冠树种密度较低。此外，由于各矮林林分的物种、大小和年龄组成以及矮林和/或种子等繁殖来源都不相同，因此不能通过一般的方法将矮林林分转化为高林。从天然混交林的光环境出发，分析了日本杉幼树的分布格局、大小和年龄结构，日本杉主要在伐根周围和因伐根拔除而扰动的土壤上生长。山毛榉在土壤上的更新具有传染性，但丛内比较均匀。拔根后形成的土丘为逃避矮生竹压制的鹤望兰提供了良好的生境，天然更新系统具有典型的多物种特征。在恢复体系中，必须考虑天然林中苗木生态性状的差异。其次，阐明了山毛榉/栎次生林恢复过程中冠层发育与树干生长格局的关系。因此，我们建议在矮林中进行间伐时，应在小冠干的汇合处进行。如果高质量的茎干不存在小冠收敛，则群伐可能是一种合适的方法。在这种情况下，群体大小应与小冠收敛的估计大小相联系。这将给次生林带来不均匀的年龄结构。

A coppice stand which had been utilized intensively contained lower densities in canopy tree species. Furthermore, specie, size and age compositions, and also the reproductive origins, such as coppice and/or seed, are various in each coppice stand. Therefore, coppice stands can not be converted into high forests by common practics.Firstly, we focussed on the early regeneration phase in the gaps which allow several species to coexist. The dispersion pattern and also size and age structure of saplings were analyzed in concerning with the light environments in natural mixed forest.Japanese cedar which mainly established contagious around the stumps and on disturbed soil due to uprooting stumps. Beech regenerated on the soil contagious but intra-clump was rather uniform. The mounds which were created by uprootings provide a good habitat for A.turbinata escaping form suppression of dwarf bamboo.Natural regeneration systems are typically multi-species. In the restoring system, we have to consider the differences of ecological traits of seedlings and saplings revealed in natural forests. They should be applied to multi-spscies regeneration in practical forestry.Next, we clarified the relation between canopy development and stem growth patterns in restoring process of beech/oak secondary forest. As a result, we recommended that thinning in coppice stand should be done where the stem with small crown converged. If the high-quality stems are not exist in a small crown convergence, group cutting may be a suitable method. In this case, group size should be connected with the estimated size of small crown convergence. It will bring un-evenaged structure to the secondary forests.