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出 处:《湖北林业科技》2005年第6期8-12,共5页Hubei Forestry Science and Technology
摘 要:通过对杨树中汉107号无系性幼林采样测定发现,2~8a生幼树胸径处去皮后木材基本密度、纤维含量、纤维长度都随树龄增加而略增大,分别于第6年、第6年、第5年时基本上稳定下来,达到工艺成熟;幼树木材连年生长量总体趋势是随着年龄的增加而增大,第7年时达到极高值,第8年开始下降。综合杨树不同树龄时生长与木材材性情况,杨树的主伐期定为8a是比较理想的。另外通过对杨树1~5a蔸1a生苗杆的各项指标测定表明:采用“割韭菜”式的经营杨树直接用于制浆、人造板,工艺上是不成熟的。It was found by measurement through sampling Zhonghan No. 107 clone of populus tree from the young forest that a basis stability and technical maturity can be aimed for wood properties such as basic density, fiber content and fiber length after peeling respectively in the sixth, sixth and fifth year; the general trend for current annual increment is increment along with age in which it reaches the maximum in the seventh year and drop again in the eighth year. According to wood qualities and growth in different tree ages, the 8 years is more ideally designated as final felling period. In addition, the measurement on various indicators for 1-year-old seedling stem of populus tree with 1-5 year old roostock showed that technical maturity was not yet adopting manaegment upon pupulus of “cut chives” pattern which was put into use directly on pulping-making and wood-based panel making.
分 类 号:S791.270.5[农业科学—林木遗传育种] S792.11[农业科学—林学]
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