闽楠天然林与人工林木材物理力学性质研究

Study on Physical and Mechanical Properties of Phoebe bournei Wood from Plantation and Natural Forest

对闽楠人工林和天然林木材物理和力学性质进行了测定和比较分析,结果表明:闽楠天然林木材气干密度和全干密度分别为0.721 g.cm-3和0.680 g.cm-3,人工林木材气干密度和全干密度分别为0.572 g.cm-3和0.535 g.cm-3,闽楠天然林木材密度大于人工林且差异达到极显著水平,但人工林木材密度变异系数却小于天然林。闽楠人工林和天然林木材气干状态下体积干缩率分别为4.935%和6.439%,全干状态下分别为9.330%和11.376%,闽楠人工林木材的尺寸稳定性稍差于天然林,但从木材的差异干缩来看,闽楠天然林和人工林相近,分别为1.75和1.76。闽楠天然林木材端面、径面和弦面硬度分别为7 583 N、6 183 N和6 625 N,稍大于人工林,但差异不显著。闽楠天然林与人工林旋切板背面裂隙率分别为53%和67%,单板厚度的偏差人工林和天然林分别为0.08mm和0.09 mm。由此可知,发展闽楠人工林可以得到质量与闽楠天然林相近的板材。

Based on studying the physical and mechanical properties of Phoebe bournei wood from plantation and natural forest, the results showed that the air-dry density and oven-dry density of P. bournei wood from natural forest were 0.721 g · cm^-3 and 0. 680 g · cm^-3, that from plantation were 0.572 g · cm^-3 and 0. 535 g · cm^-3. The difference of wood density between natural forest and plantation was extremely significant, but the wood density variation coefficient of plantation was less than that of natural forest. The wood volume shrinkage ratio of P. bournei plantation and natural forest under air-drying condition were 4. 935% and 6. 439%, while under oven-dry condition, they were 9. 330% and 11. 376% respectively, which meant that the dimensional stability of wood from P. bournei plantation was poorer than that from natural forest, but their ratios of tangential to radial direction were 1.75 and 1.76. The rigidities of P. bournei wood from natural forest in surface, radial and tangential directions were 7 583 N, 6 183 N and 6 625 N respectively, which was higher than that from plantation. P. bournei natural and plantation wood veneer rotary cutting back cracking rate were 53% and 67% and their veneer thickness deviation were 0.09 mm and 0.08 mm. It was proved that the properties and quality of P. bournei wood from plantation and natural forest were similar.