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A NON-DESTRUCTIVE FIELD MEASUREMENT OF STEM MOE FOR EVALUATING WOOD QUALITY IN STANDING TIMBER

用于评估立木木材质量的茎 MOE 无损现场测量

基本信息

批准号：
61560179
负责人：
UEDA Koji
金额：
$ 1.09万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1987
项目状态：
已结题

项目摘要

This invesigation deals with a field instrument capable of determining the bending modulus of elasticity (MOE) in the stem of standing trees and the application of the instrument to some plantation grown Japanese larch stands.The MOE calculation is based upon the deflection of the stem. The bending moment is generated by a weight applied on a lever-arm attached to the stem. The deflection is detected by the middle-ordinate gage placed on the convex side of the bent stem.Results are summarized as: 1. The increase of MOE in larch trees was remarkable from 10 to 20 years of age, and thereafter it gradually became stable. 2.The MOE of the stems agreed well with laborarory tests on logs obtained from sample trees. 3. The MOE values of 136 stems at 13 larch stands were in the range of 60-150 t/cm^2. 4. The effect on MOE values by growth rate was little within a stand. The coefficient of variation for MOE in each stand was about 12%. 5. Differences of average MOEs between larch stands in the same area were found, which may have been due to local environmental condition such as slope exposure. 6. A test in a larch clone stand derived from 52 plus-trees did not show any superiority in MOE to the above mentioned larch stands, while the inter-clone deviation was little.The method proposed in this study may be utilized for the assessment of wood quality in live trees, the selection of trees for thinning cut and/or the selection of plus-trees from the wood quality viewpoint.

本文介绍了一种能测定立木树干弯曲弹性模量（MoE）的野外仪器及其在日本落叶松种植园林中的应用。弯矩是由施加在连接到股骨柄的悬臂上的重量产生的。通过在弯曲柄的凸侧放置中坐标规来检测挠度。落叶松的莫伊在10 ~ 20年生时增加显著，此后逐渐趋于稳定。2.茎的莫伊与对从样本树获得的原木进行的实验室测试一致。3. 13个林分的136个树干的莫伊值在60-150 t/cm ^2之间。4.生长速率对莫伊值的影响在林分内较小，各林分的莫伊变异系数在12%左右。5.同一地区落叶松林分的平均弹性模量存在差异，这可能与当地的环境条件（如坡面暴露）有关。6.对52株优树的落叶松无性系林分的测定表明，其抗弯强度（莫伊）与上述无性系林分相比无明显优势，而无性系间的差异较小，本研究提出的方法可用于活木木材品质的评定、间伐树的选择和优树的选择。