不同林分长白落叶松木材气干密度和主要力学性质的变异性与相关性

Variability and relationship between wood density and main wood mechanical properties in different stand Larix olgensi

以4个不同林分密度下的9株长白落叶松木材为实验材料,依据国家标准(GB 1927～1943—2009)对其抗弯弹性模量、抗弯强度、顺纹抗压强度和气干密度等主要物理力学性质进行了比较研究。结果表明:林分密度为580株/hm2的长白落叶松木材的抗弯弹性模量、抗弯强度、顺纹抗压强度、气干密度的均值均高于其他3个林分,而且气干密度在四个不同林分间的差异水平均在0.01水平显著。相反,林分密度为200株/hm2的长白落叶松木材的各种物理力学均值最小。4个林分密度下的长白落叶松木材主要力学性质在纵向均呈现下降趋势,方差分析表明抗弯弹性模量和抗弯强度纵向上的变异在0.05水平显著,顺纹抗压强度、气干密度均在0.01水平显著。长白落叶松木材的气干密度与抗弯弹性模量、抗弯强度、顺纹抗压强度呈线性正相关,决定系数分别为0.652、0.562和0.736。

Nine sample trees of Larix olgensi from four different stands were selected as the testing materials. The MOE（modulus of rup- ture）, MOR（modulus of rupture）, compression strength parallel to grain and wood density of different stand Larix olgensi were studied with National Standard（GB 1927 ～ 1943-2009）. The results show that the MOE, MOR, compression strength parallel to grain and air- dry density of Larix olgensi with 580 stand density were higher than others, and the difference of air-dry density among the four stands was at 0.01 level. On the contrary, all physical and mechanical indexes of 200 stand density of Larix olgensi were lowest. All main me- chanical peroperties of Larix olgensi from different stand decreased in longitudinal direction. MOE and MOR have a difference （at 0.05 level） in longitudinal direction, and compression strength parallel to grain, air-dry density had a significant difference （at 0.01 level）. The air-dry density and mechanical properties were statically significant difference （at 0.01 level）, and wood air-dry density had positive lin- ear relationship with other mechanical properties which R 2 were 0.652, 0.562 and 0.736.