不同生态条件对人工林杨树木材物理力学性质的影响

在施肥与未施肥、淹水与未淹水两种生态条件下,以杨树人工林木材I-69杨为对象,对木材年轮宽度、基本密度、干缩性质、主要力学性质进行了测试,并对数据进行了统计、对比和分析.结果表明,施肥处理后,木材年轮宽度、静态抗弯弹性模量和顺纹抗压强度分别增大0.99%、2.73%和1.06%;全干时和气干时的径向、弦向、体积全干干缩率分别降低了4.2%、7.7%、6.6%、15.6%、6.3%和11.1%;木材密度、抗弯强度、动态抗弯弹性模量则分别降低了2%、1.79%、8.13%.与未淹水相比,季节性淹水对I-69杨木材密度、木材干缩率和力学性质的影响较大,二者差异显著(P＜0.05).其中木材密度、全干时和气干时的径向、弦向、体积干缩率、抗弯强度、抗弯弹性模量以及顺纹抗压强度分别降低了5.5%、11.1%、9.2%、9.6%、16.7%、10.9%、8.5%、24.29%、18.18%和16.81%.

Physicomechanical properties of plantation poplar wood under different eco-environments

The measurement of the physicomechanical properties of 9 plantation poplar I-69(Populus deltoides CV.I-69/55)woods under fertilization and seasonal flooding showed that compared with no fertilization,fertilization increased the ring width,static modulus of elasticity,and compressive strength parallel to the grain by 0.99%(P>0.05),2.73%(P<0.05)and 1.06%(P<0.05),while decreased the air-dry radial,tangential,volumetric shrinkage,oven-dry radial,tangential,volumetric shrinkage,basic density,MOR,and dynamic modulus of elasticity by 4.2%,7.7%,6.6%,15.6%,6.3%,11.1%,2%,1.79% and 8.13%,respectively.Seasonal flooding decreased the basic density,air-dry radial,tangential,volumetric shrinkage,oven-dry radial,tangential,volumetric shrinkage,MOR,MOE,and compressive strength parallel to the grain by 5.5%,11.1%,9.2%,9.6%,16.7%,10.9%,8.5%,24.29%,18.18% and 16.81%,respectively,in comparing with non-flooding.