对不同立地条件(不同地带和地形)下米老排(Mytilaria laosensis Lecomte)人工林胸径和树高生长以及木材品质的差异进行了比较分析。结果表明:相同地形条件下生长于南亚热带的米老排人工林林分胸径和树高以及木材密度、顺纹抗压强度和抗弯强度大于生长于中亚热带的,而木材尺寸稳定性小于生长于中亚热带的。相同地带内山谷中的米老排人工林林分胸径和树高以及木材尺寸稳定性大于山脊上的;木材密度、顺纹抗压强度和抗弯强度则小于山脊上的。差异显著性t检验表明:立地条件(地带和地形)对米老排人工林林分胸径和树高影响均极显著,对米老排人工林的木材密度、顺纹抗压强度和抗弯强度影响极显著或显著;地形对米老排人工林的木材差异干缩影响极显著或显著,地带的影响不显著。研究结果为米老排人工林培育和木材合理利用提供科学依据。

Differences of DBH(diameter at breast height)growth, height growth and wood quality of Mytilaria laosensis Lecomte plantations in different site conditions(including different regions and terrains)were analyzed comparatively. The results showed that under the same terrain condition, DBH and height of M. laosensis plantation stand aswell as density, compression strength parallel to grain and bending strength of M. laosensis wood from plantation growing in southern subtropic were bigger than that in middle subtropic, while size stability of M. laosensis wood from plantation growing in southern subtropic was smaller than that in middle subtropic. In the same region, DBH and height of M. laosensis plantation stand, as well as size stability of M. laosensis wood from plantation growing in the valley were bigger than that on the ridge, while density, compression strength parallel to grain and bending strength of  M. laosensis wood from plantation growing in the valley were smaller than that on the ridge. Difference significance t test showed that site conditions(either region or terrain)influenced extremely significantly on DBH and height of M. laosensis plantation stand and affected extremely significantly or significantly on density, compression strength parallel to grain and bending strength of M. laosensis wood from plantation. Terrains influenced extremely significantly or significantly on

ratio of tangential shrinkage to radial shrinkage, but regions affected not significantly. The conclusions provide a scientific basis for plantation cultivation and rational wood utilization of M. laosensis forest stand.