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五株山杨试材采自山西省中条山同一天然林分内,其木材物理力学性质在杨属中为中等。纤维形态不亚于其它杨木。木材纤维长度及直径自髓心向外的变化,首先迅速增加,15年之后,增加速度降低,达到最大值。纤维长度及直径沿树干主轴自基部向上逐渐降低。髓心附近的木材密度高于外层,随树龄的增加而降低;沿主轴向上,木材密度先自基部到中部降低,中部向顶端增加。木材构造分子及木材密度的径向变异表明,木材幼龄期在15年生范围内。
Five strains of Populus euphratica were collected from the same natural forest in Zhongtiaoshan of Shanxi Province, and the physical and mechanical properties of the wood were medium in Populus. Fibers form no less than other poplar. Wood fiber length and diameter changes from the medullary outward, the first rapid increase, after 15 years, increasing the speed to reduce, reaching the maximum. Fiber length and diameter along the trunk axis from the base upward gradually decreased. The density of wood near the center of the pith is higher than that of the outer layer, and decreases with the increase of the tree age. Along the main axis, the density of wood decreases from the base to the middle and the middle increases toward the top. The radial variation of wood structural elements and wood density shows that the wood age is within 15 years of age.