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机构地区:[1]四川农业大学,四川雅安625014 [2]辽宁省阜蒙县福兴地学校,辽宁阜蒙123106 [3]日本鸟取大学
出 处:《辽宁林业科技》2009年第1期14-17,共4页Liaoning Forestry Science and Technology
摘 要:对章古台地区不同密度樟子人工林松年轮宽度和管胞长度进行测定,结果表明:章古台地区胸径年轮数30a的樟子松林,已出现生长衰退现象,生长衰退期开始林龄与林分密度有关,降低林分密度可延缓衰退期出现林龄。樟子松管胞长度与距离髓心的年轮数之间存在Y=alnx+b(Y:管胞长度;X:距离髓心的年轮数;b:第1年轮的管胞长度)关系。不同密度樟子松年轮宽度不同,但管胞长度与未成熟材范围无显著变化,未成熟材范围距离髓心的年轮数均为21~23a。The ring width and tracheid length for different densities of artificial Pinus sylvestris vat. mongoliea plantations in Zhanggutai were measured. The results indicated that growth declined in Pinus sylvestris var. mongolica plantations with ring number 30 in Zhanggutai. Starting ages for growth decline were correlated with ages and densities of stands and could be delayed by decreased densities of stands. The relationship between Iracheid length and ring number from pith of Pinus sylvestris vat. mongolica could be described by a semi-logarithmic formula of Y=αLnX+b ( Y=Tracheid length, X= Ring number from pith, a= coefficient, b=tracheid length in the first annual ,ring). Ring width of Pinus sylvestris var. rnongolica was different for different densities of stands. Tracheid length has no obvious correlation with ranges ofjuvenile wood, and the ring numbers ofjuvenile wood ranges from pith were averagely 21-23a.
分 类 号:S781[农业科学—木材科学与技术]
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