摘要
以长江滩地 3种栽植密度 (株行距分别为 3m× 4 m,4 m× 5m,5m× 6m)下的 3个品系速生人工林杨树木材 [欧美杨无性系 72杨 ( Populus× euramericana cv. -72 /58) ,美洲黑杨无性系 63杨( P.deltoidescv. -63/51 )和 69杨 ( P.deltoidescv. -69/55) ,以下简称 72杨、 63杨、 69杨 ]为对象 ,探讨不同栽植密度对杨树人工林木材性质的影响。结果表明 :( 1 )同一无性系在不同栽植密度下以及相同栽植密度下不同无性系杨树纤维形态特征、微纤丝角、组织比量值都有差异 ,方差分析结果表明 :除 63杨和 69杨胞壁厚度、壁腔比、柔性系数和 72杨微纤丝角、木射线比量在 3种栽植密度下差异显著外 ,其余性状差异不显著 ,说明林分初植密度对多数解剖性质无显著影响。 ( 2 )不同品系杨树在不同栽植密度下主要解剖特征的径向变异趋势基本相同 ,但变异幅度随不同栽植密度、不同品系和解剖特征而不同。其中 ,壁腔比、微纤丝角、导管比量、木射线比量随栽植密度变化变幅最大 ,而纤维长度、纤维比量变幅较小 ,但所有解剖特征的径向变异曲线在 6年左右都有一个明显的过渡点。 ( 3)栽植密度对 72、 63、 69杨木材物理力学性质的影响因材性指标的不同而不同 ,总体来说 ,栽植密度越大 ,基本密度、抗弯弹性模量和抗弯强度越小 。
Three kinds of fast growing poplar clone [Poplar 72 (Populus×euramericana cv.Ⅰ 72/58),Poplar 63 (P.deltoides cv.Ⅰ 63/51),Poplar 69(P.deltoides cv.Ⅰ 69/55],which were grown in three different spaces (3 m×4 m,4 m×5 m and 5 m×6 m),were selected to investigate the influence of spaces on wood quality in this paper.The results showed that:(1) There were large differences for the fiber morphology features,microfibril angle and tissue proportions of poplar in different trees of the same spaces or different spaces of the same clones.Variance analyses showed that only the thickness of cell wall,ratio of cell wall to lumen,fiber flexible coefficients of poplar 63,poplar 69 and microfibril angle,ray proportion of poplar 72 were significant among three different spaces.It indicated that the selected spaces had no significant effects on the most anatomical properties.(2) The variation patterns of main anatomical features were similar for the different clones in different spaces,but the variance ranges were different in different spaces,clones and properties.The variance ranges of the ratio of cell wall to lumen,the microfibril angle,vessel proportion and ray proportion were large,but that of the fiber length and fiber proportion were small.There existed an obvious transfer point at six year in all variation curves of the anatomical features.(3) The effects of spaces on wood physi mechanical properties of poplar 72,poplar 63 and poplar 69 changed with different wood properties.The general results were that the wider the spaces,the smaller the basic density,the modulus of elasticity and the modulus of rupture,and the larger the total shrinkage.Variance analyses indicated that the selected spaces had significant effects on the most physi mechanical properties of poplar 72 and poplar 69.
出处
《安徽农业大学学报》
CAS
CSCD
2000年第4期374-379,共6页
Journal of Anhui Agricultural University
基金
国际科学基金项目资助
