间伐强度对湿地松木材性质的影响规律研究

Effects of Thinning Intensity on Wood Properties of Slash Pine

通过对不同间伐强度处理 (未间伐、弱度 (伐去株数 18 6 % )、中度 (伐去 35 7% )、强度 (伐去5 2 9% ) )的 19年生湿地松林分其林木木材的主要材性指标进行全面测试分析研究 ,结果表明 :间伐后 8a ,间伐强度对湿地松木材气干密度、全干密度、径向全干缩率、体积全干缩率、差异干缩、顺纹抗压强度、抗弯强度、弹性模量、径向抗剪强度及端面硬度有显著影响 ;随着间伐强度的增大 ,树干年生长轮平均宽度、木材差异干缩是增大的 ,而随间伐强度的增加木材气干密度、全干密度有不同程度的减小 ,木材顺纹抗压强度、抗弯强度、抗弯弹性模量、硬度等主要力学性质则是呈先增加后减小的趋势。

Wood properties of 19 years old slash pine from four plots subjected different thinning intensity(0%?18 6%?35 7%?52 9%)were determined and analyzed. Results show that thinning intensity had significant or highly significant effects on air dry specific gravity, oven dry specific gravity, radial and volume total shrinkage, shrinkage ratio (tangential to radial direction), compression strength parallel to grain, bending strength, modules of elasticity, radial shearing strength, and the cross section hardness after thinning for 8 years; with the increase of thinning intensity, the width of growth ring and the shrinkage ratio increased, whereas the air dry specific gravity and oven dry specific gravity decreased to certain degree, and the compression strength parallel to grain, bending strength, modules of elasticity, and hardness increased at first and then decreased.