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受酸雨危害和未受酸雨危害的杨树木材性质的对比表明 :酸雨对杨树生长和木材性质产生显著的影响。与未受危害的健康材相比 ,危害材的木素和戊聚糖含量相对升高 3.72 %和 1 .43% ,而综纤维素的含量相对减少 3.45 % ,热水抽出物、苯 -醇抽出物和 1 % Na OH抽出物含量明显高于健康材。基本密度、气干密度和全干密度分别降低2 .6 2 %、1 .75 %和 1 .1 9% ;危害材的生材含水率较健康材低 ,边材含水率的差异较大 ,心材含水率差异较小 ;弦向干缩率相对增大 1 0 .77% ,径向干缩率相对减小 1 6 .88% ;弹性模量和冲击韧性较低 ,两者有显著差异 ,而抗弯强度较健康材相对增大 9.5 5 %。酸雨引起杨树木材性质的变异对杨木的加工利用有一定的影响。
A comparison of the properties of poplar wood, harmed by acid rain and not harmed by acid rain, shows that acid rain has a significant effect on poplar growth and wood properties. The contents of lignin and pentosan in hazardous materials increased 3.72% and 1.43% relative to the unhealthy healthy material, while the relative content of holocellulose decreased 3.45%. Hot water extract, benzene-alcohol Extracts and 1% Na OH extract content was significantly higher than healthy material. The basic density, air-dry density and total dry density decreased by 2.62%, 1.75% and 1.19% respectively. The moisture content of raw materials of hazardous materials was lower than that of healthy materials, and the difference of moisture content of sapwood was larger, The moisture content of heartwood is smaller; the shrinkage in chordwise direction is relatively increased by 10.77%, the radial shrinkage is decreased by 16.88%; the elastic modulus and impact toughness are low, The flexural strength is 9.5% higher than that of healthy material. The variation of wood properties caused by acid rain has a certain impact on poplar processing and utilization.