马尾松木材性状株内变异与木材取样方法的探讨

试验表明,马尾松木材比重、管胞长度和晚材率的株内变异,由髓心至树皮,由树干基部至树干顶端存在着巨大的变异,这对材性研究造成了一定的困难,但为选择幼龄材含量较少,材性较均匀的树木提供了可能性。同时,用胸高处任一方位半径的木材样品估算树干材性均值,可达到非破坏性取样的目的。

WITHIN-TREE VARIATION OF WOOD PROPERTIES AND REASONAL APPROACH TO SAMPLING WOOD IN PINUS MASSONIANA LAMS

Within-trcc variation of specific gravity, tracheid length and latewood percent of masson pine was studied in details. The study shows that large variations existed of wood properties from pith to bark and from tree base to the tip. It was basic radial variation of three wood characteristics to increase gradually with age from the pith, and to trend to level off or to decrease lightly after the maximum. Specific gravity and latewood percent decrease with height from tree base to the tip, and while tracheid length increases with height within some distance from tree base, and decreases slightly after the maximum. The longest tracheid length was found within the outerest at 1/3 stem height. Strong correlation existed between breast height value and average stem value for specific gravity. No significant difference among radial cardial directions within breast height was found for specific gravity and tracheid length. It was satisfactory to use nondestructive approach to evaluating average stem value of wood properties using any direction sample at breast height.