摘要
【目的】探明米老排Mytilaria laosensis人工林节子的时空分布特征及变色规律,为培育米老排无节材提供理论参考。【方法】以位于广西凭祥市的中国林业科学研究院热带林业实验中心11年生米老排人工林为研究对象,选取20株米老排样木,利用节子解析的方法,对获得的1 101个完整节子进行研究。【结果】从节子发育年龄上,米老排的枝条主要从第1~2年开始生长,第2~4年是其死亡高峰期(91.9%),这些枝条(87.2%)死亡后在第5~8年内完全愈合并形成节子,其中大部分节子(76.7%)的愈合时间为3~6 a;在第2~4年米老排枝条死亡数量较多,该时段是控制节子形成的关键时期。在节子垂直分布上,节子的数量呈现随树高的增加先上升后急剧下降的趋势,且主要集中在高度为0~8.0 m的树干上。节子变色长度与节子的直径和愈合时间呈显著正相关(P<0.05),但与分枝角度呈显著负相关(P<0.05)。通过逐步回归,得出节子直径、死节长度、节子出现年龄以及愈合时间是影响米老排节子变色长度的关键因子,相关性达极显著水平(P<0.01)。【结论】在米老排种植后的2~4 a,对树干8.0 m以下进行首次修枝,有助于该树种无节材的培育。采取相应的森林培育措施减小枝条基径和缩短节子愈合所需时间,有助于减少节子对木材带来的影响。图7表4参32。
[Objective] The objective is to explore the spatial and temporal distribution characteristics and discoloration law of knots in the Mytilaria laosensis plantation,so as to provide theoretical reference for the cultivation of clear wood.[Method] A total of 1 101 complete knots were obtained by knot analysis from 20trees of 11-year old M.laosensis plantation in Experimental Center of Tropical Forestry in Pingxiang City of Guangxi.[Result] In the development age of the knots,the branches of M.laosensis mainly began to grow in the 1st and 2nd year,and the death peak came in the 2nd to 4th year(91.9%).These branches(87.2%)completely healed and formed knots in the 5th to 8th year after death,and the healing time of most of them(76.7%) was 3 to 6 years.More branches of M.laosensis died in the 2nd to 4th year,which was a critical period to control the formation of knots.In the vertical distribution,the number of knots increased first and then decreased sharply with the increase of tree height and they were mainly concentrated on the trunk with a height of 0-8.0 m.The discoloration length of knots was positively correlated with knot diameter and healing time(P<0.05),but negatively correlated with branch angle(P<0.05).Through stepwise regression,it was concluded that knot diameter,dead knot length,knot age and knot healing time were the key factors affecting knot discoloration length,and their correlation was very significant(P<0.01).[Conclusion]Pruning the trunk below8.0 m for the first time 2-4 years after planting is beneficial to the cultivation of clear wood.Taking corresponding forest cultivation measures to reduce the base diameter of branches and the time required for knot healing will help ease the impact of knots on wood.[Ch,7 fig.4 tab.32 ref.]
作者
何韦均
杨锦昌
郝建
董明亮
余纽
覃国铭
李荣生
HE Weijun;YANG Jinchang;HAO Jian;DONG Mingliang;YU Niu;QIN Guoming;LI Rongsheng(Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,Guangdong,China;Experimental Center of Tropical Forestry,Chinese Academy of Forestry,Pingxiang 532600,Guangxi,China)
出处
《浙江农林大学学报》
CAS
CSCD
北大核心
2022年第4期814-820,共7页
Journal of Zhejiang A&F University
基金
广东省林业科技创新项目(2016KJCX004,2019KJCX004)。
关键词
节子
米老排
变色长度
时空分布
预测模型
knots
Mytilaria laosensis
discoloration length
spatial and temporal distribution
prediction model