ABSTRACT

The management of abandoned coppiced forests is an important issue for sustainable forestry. Lithocarpus edulis (Fagaceae) is a rarely-used hardwood species in Japan, although it is an abundant and fit species for resource utilization. This study aimed to clarify the variation of the stress-wave velocity (SWV) of stems among and within stands of L. edulis. The stem height, stem diameter, and SWV were measured for the coppices grown in five stands from the Boso Peninsula in Chiba, Japan. Significant differences among the stands were observed for all traits. A linear mixed model revealed that the tree variance component accounted for more than 30% of the stem height and diameter and 40% of SWV, suggesting the large contribution that tree effects have on the variation of these traits. This tree effect is favorable to improve these traits genetically. Compared to size traits, the stand age had a minimal effect on stand-level SWV values, and younger stands tended to show high SWV values. Although the number of coppiced stems per stump had a negative impact on the stem diameter, it showed no effect on SWV, suggesting that early thinning is also important to achieve both a desirable radial growth and wood quality.

摘要

废弃林地的管理是可持续林业的一个重要问题。Lithocarpus edulis (Fagaceae)在日本是一种很少使用的硬木树种，尽管它是一种丰富且适合资源利用的树种。本研究旨在阐明应力波速度（SWV）的变化的之间和L的看台内茎贻贝. 测量了生长在日本千叶房总半岛 5 个林分的矮林的茎高、茎直径和 SWV。对于所有性状，观察到林分之间的显着差异。线性混合模型显示，树木方差分量占茎高和直径的 30% 以上，SWV 的 40%，表明树木效应对这些性状变异的贡献很大。这种树效应有利于在遗传上改善这些性状。与大小性状相比，林龄对林分级 SWV 值的影响最小，年轻林分往往表现出较高的 SWV 值。虽然每根残端的茎秆数量对茎秆直径有负面影响，但对 SWV 没有影响，