共查询到18条相似文献，搜索用时 187 毫秒
1.
杉木材性株内的变异Ⅱ.管胞形态的变异 总被引：5，自引：0，他引：5
对浙江产杉木株内不同高度和圆周不同方位上木材的管胞长度、宽度、长宽比的径向变异模式和木材力学性质与管胞形态的相关关系进行了测定和分析。结果表明：管胞长度、宽度和长宽比的径向变异模式，在株内不同高度和圆周不同方位上大致相似（长宽比在不同方位上除外），管胞形态与年龄呈显著正相关（在０．０１水平）。广义方差分析表明在株内不同高度上，管胞长度、宽度、长宽比差异不显著；在圆周不同方位上长宽比差异显著，其余两项末表现出显著差异；不同年龄间管胞长度、宽度、长宽比均差异显著。在不同高度上，三项力学性质中，只有抗弯强度和管胞长度０．０５水平显著相关，其余相关不显著。 相似文献
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杉木材性株内的变异：II.管胞形态的变异 总被引：2，自引：1，他引：2
以浙江产杉木株内不同高度和圆周不同方位上木材的管理长度，宽度，长宽比的径向变异模式和木材力学性质与管胞形态的相关关系进行了测定和分析，结果表明：管胞长度，宽度和长宽比的径向变异模式，在株内不同高度和圆周不同方位上大致相似（长宽比在不同方位上降外）管胞形态与年龄呈显著正相关（在０．０１水平），广义方差表明在株内不同高度上，管胞长度，宽度，长宽比差异不显著；在圆周不同方位上长宽比差异显著，其余两项未表 相似文献
3.
杉木材性株内变异的研究Ⅰ.木材力学性质和木材密度 总被引：2，自引：0，他引：2
对１５株浙江产杉木株内不同高度和圆周不同方位上木材的抗弯强度、抗弯弹性模量、顺纹抗压强度和木材密度的差异，木材密度的径向变异模式和木材力学性质与木材密度的相关关系进行了测定和分析。主要结果是：抗弯强度和抗弯弹性模量在株内不同高度上差异特别显著；顺纹抗压强度和木材密度未表现出显著差异；在圆周不同方位上，三项力学性质和木材密度均为南北向高于东西向，差异不显著；木材密度径向变异模式在不同高度和不同方位上均为接近水平有一定波动的直线；三项力学性质与木材密度的相关关系在不同高度和不同方位上均特别显著，但不同力学性质与木材密度的相关系数有明显差异，不同高度上和圆周不同方位上，亦有差异。 相似文献
4.
杉木材性株内变异的研究 总被引：6，自引：0，他引：6
对１５株浙江产杉木株内不同高度和圆周不同方位上木材的抗弯强度、抗弯弹性模量、顺纹坟强度和木材的差异，木材密度的径向变异模式和木材力学性质与木材的相关关系进行了测定和分析。主要结果是：抗弯强度和抗弯弹性模量在株内不同高度上差异特别显著；顺纹抗压强度和木材密度未表现出显示差异；在圆周不同方位上，三项力学性质和木材密度均为南北向高于东西向，差异不显著；木材密度径向变异模式在不同高度和不同方位上均为接近水 相似文献
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对30株蓝桉、36株直干桉胸高圆盘上不同方向、年龄及树干不同高度的木材纤维长度所作的测定分析表明：两树种株内木材纤维在不同方向的差异不显著,年龄间、高度间的差异极其显著(P＜0001)。在11年生以前,纤维长度随年龄的增长几乎是直线上升,其变异可用对数曲线描述。纤维长度以胸高圆盘的平均值最短,其次为树高的3/4处,树干中部纤维较长。2年生与主伐时(8年)的纤维长度相关极显著(达0.01水平)。两树种间纤维长度差异均极其显著,区组间差异却不显著。蓝桉家系间差异显著(P＜0.05),直干桉家系间差异却不显著。 相似文献
6.
蓝桉,直干桉木材纤维长度在株内的变异 总被引：3，自引：1，他引：2
对３０株蓝桉、３６株直干桉胸高圆盘上不同方向，年龄及干不同高度的木材纤维长度所作的测定分析表明，两种树种株内木材在不同方向的差异不显著，年龄间、高度间的差异构其显著（Ｐ〈０．００１）。在１１年生以前，纤维长度随年龄几乎是直线上升，其变异可用对数曲线描述。纤维长度以胸高圆盘的平均值最短，以前，纤维长度随年龄的增长几科是直线上升，其变异可用对数曲线描述。纤维长度以胸高圆盘的平均值最短，其次为树高的３／ 相似文献
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8.
扁担木生物量及纤维形态的测定 总被引：1，自引：0，他引：1
对扁担木生物量、木纤维含率及其长度、宽度的测定结果表明：（１）单株生物量、木纤维含率与株龄呈正相关；（２）株龄对木纤维含率、纤维形态没有明显影响，但土地条件对纤维形态影响比较显著，而产地没有影响；（３）扁担水木纤维与韧皮纤维含率及形态有显著变化，韧皮纤维含率４５．１８％，纤维均长８９１、６ｕｍ，长宽比５６．８１；木纤维含率５８．１１％，纤维均长７４８．９ｕｍ，长宽比５０．７０。扁担木是优质纤维经济灌木树种，应深入进行其开发利用的研究。 相似文献
9.
人工林尾巨桉株内、株间纤维形态变异的研究 总被引：2，自引：0，他引：2
对5株13年生的尾巨桉纤维形态的径向变异进行研究,在显微镜下观察木材解剖构造,同时对纤维长、纤维宽、胞壁厚和纤维长宽比进行了测量.结果表明:尾巨桉属阔叶散孔材,纤维形态指标径向上具有增大的趋势,株内径向上各纤维形态指标差异显著,株间略有差异.尾巨桉木材平均纤维长0.73~1.01 mm,胞壁厚4.36~5.09μm,纤维长宽比42~51,能满足纤维工业原料的要求,属较好的纸浆工业用材. 相似文献
10.
柳树纤维性状遗传变异的研究 总被引：6，自引：3，他引：3
柳树的纤维长与纤维素含量在苗期即有显著差异，其纤维长的遗传变异，无论是在杂种（家系）间，还是在杂种（家系）内无性系间都是显著的。纤维直径和长径比尽管在苗期的差异不显著，但在林期与纤维长一样，无性系间的差异是极显著的。通过杂交组合和无性系选择改良柳树的纤维性状是可行的。无性系内不同年龄间纤维性状的差异是显著的，这为确定纸浆林的轮伐期提供了参考依据。 相似文献
11.
Important wood, pulp and fibre properties were investigated on small wood samples from two Rumanian, one German and one Norwegian provenance of Norway spruce (Picea abies) grown in Sørkedalen, Norway. Several samples were collected from inside each single tree, both in radial and transversal direction in the stem. Data were collected from a total of 59 trees, each 28 years of age. All investigated properties showed close relationship to ring number (RN) (cambium age). For basic density and fibre wall thickness (FWT), a fast decline was first observed when moving from pith to bark and a minimum value was found around RN 5–8. The declining trend was then followed by an increase. Kraft pulp yield, fibre length and fibre width (FW) also increased with RN, but the increase was most pronounced close to the pith. The pulp yield (PY) more or less stabilised outside of RN 5–6. FW showed a decrease outside of RN 10–12, but this was probably due to the remarkable simultaneous drop in ring width for the investigated trees. FW decreased, while basic density and fibre length increased with increasing height in the tree. PY and FWT were not affected by height in tree. Diameter at breast height (DBH) was the most important variable indicating differences between trees in the investigated material. Basic density, fibre length and FWT decreased, while FW increased with increasing DBH. Height to crown had a positive effect on basic density, but had no influence on any of the remaining properties. Differences between provenances were found for basic density, fibre length and FW. The analyses showed that it is possible to describe the variation inside and between trees satisfactorily for a range of important wood and fibre properties. 相似文献
12.
海南岛柚木的木材性质 总被引：1，自引：1，他引：1
１１—１３龄柚木２０株，１７—１９龄７株，取自海南岛尖峰岭，用以研究木材比重及纤维长度的某些特性及测定标准物理力学性质。以胸高圆盘加权平均数为单元，比重０．４６６—０．５８８，平均０．５１６：纤维长度０．８７８—１．２３０ｍｍ，平均１．０６３ｍｍ。生长轮宽度与比重及纤维长度之间表现弱的负相关。第１轮和第９轮的材性存在显著的相关关系。材性在标地间的差异不显著，标地内株间的差异很显著。径向变异：髓心附近几轮的纤维长度和比重均增长很快，第８轮以后，前者增长缓慢，后者多起伏。轴向变异：１．心部系列（髓心向外６生长轮）第１轮纤维长度的轴向变异很小，其外几轮的纤维长度缓慢向上减轻或有起伏；基部各生长轮的比重很大，向上急剧减小至１．３ｍ高度，此后各生长轮的变化不一致。２．边部系列（树皮向内６生长轮）纤维长度和比重均很快向上减小。讨论了影响纤维长度轴向变异的主要因素。提出标准物理力学性质的试验结果。 相似文献
13.
Jean-Pierre Lasserre Euan G. Mason Michael S. Watt John R. Moore 《Forest Ecology and Management》2009
Pinus radiata D. Don trees from six clones, grown at initial spacings of 2500 stems ha−1 and 833 stems ha−1 were destructively harvested. For these trees wood properties were measured on radial slices sampled at a height of 1.4 m above the ground. Relative to wide spacing, close initial stand spacing significantly reduced microfibril angle (MFA) and ring width and significantly increased dynamic modulus of elasticity (MOE), fibre length, latewood percentage and cell wall thickness. Density and fibre width were not significantly different between spacing treatments. Examination of the influence of genetic population on wood properties indicated that genotype significantly influenced MFA, MOE and ring width. The key wood properties MFA, MOE and fibre length were regressed against tree diameter, height and stem slenderness. All three wood properties were most strongly correlated with stem slenderness. Multiple regression models developed for MFA, MOE and ring width accounted for respectively 62%, 81% and 58% of the variation in these variables. The following changes occurred in sampled properties with increasing ring number: MFA and ring width declined markedly; MOE and fibre length increased markedly; latewood percentage and cell wall thickness increased slightly; and density and fibre width did not show any radial trend. 相似文献
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Wood quality data from 33 sites aged between 15 and 18 years old were analysed to determine the effect of prior land use (pasture, cleared grazing land or timber) on wood density, wood stiffness, fibre length and kraft pulp yield. Sampling sites covered 6 different forest areas within the estate. Prior land use (PLU) significantly affected wood stiffness, density and fibre length but not the kraft pulping traits. In contrast, differences were found between different forest areas for the kraft pulping traits plus fibre length but not for stiffness or density. 相似文献
16.
Michael S. Watt Ryan D’Ath Alan C. Leckie Peter W. Clinton Graham Coker Murray R. Davis Robyn Simcock Roger L. Parfitt John Dando Euan G. Mason 《Forest Ecology and Management》2008
The objectives of this study were to determine the influence of site, fertilisation and age on fibre length and develop predictive models of fibre length from a comprehensive set of climatic, edaphic and stand variables. Data were collected from a nationwide set of 22 site quality plots where Pinus radiata D. Don was established at high stand densities (40 000 stems ha−1) and grown over a period of 4 years. The main environmental drivers of fibre length were identified by assessing the strength of bivariate correlations and use of multiple regression. Path analysis was used as an extension to multiple regression to separate cause from effect and quantify the direct influence of variables significantly related to fibre length. 相似文献
17.
Veli-Pekka Ikonen Heli Peltola Lars Wilhelmsson Antti Kilpelinen Hannu Visnen Tuula Nuutinen Seppo Kellomki 《Forest Ecology and Management》2008,256(6):1356-1371
In this work, empirical ring-based models were developed to predict the distribution of early wood percentage, wood density and fibre length along the stems of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) as affected by silvicultural management. The performance of the ring-based models was also compared for Scots pine and Norway spruce with corresponding disc-based (cross-sectional) models. Moreover, both models were integrated with example simulations by a process-based growth and yield model to analyze how management, such as thinning, affects the growth and wood properties of Scots pine trees over a rotation as an average for the tree stem, but also along the stem.The ring-based models built for annual early wood percentage (explained by ring width), air dry wood density (explained by early wood percentage and cambial age) and fibre length (explained by radial growth percentage and cambial age) predicted reasonably well the wood properties both at an intra-ring level, but also at a cross-sectional level. These predictions were also reasonably well in line with corresponding cross-sectional predictions by the disc-based models (which predicted the properties based on the number of annual rings and diameter at breast height and/or the cross-section being considered and temperature sum). The example simulations also demonstrated that both models predicted slightly lower wood density for dominant trees compared to dominated ones grown in thinned and unthinned Scots pine stands over a rotation. Unlike the disc-based model, the ring-based model predicted, on average, higher early wood percentage in dominant trees than in dominated ones. However, fibre length was not significantly affected when the averages of the whole stems were predicted, and this held true for both ring- and disc-based models.In summary, the incorporation of empirical ring-based wood property models into a process-based growth and yield model, offers a means to study in detail how environmental conditions, forest structure and management affect the quantity and properties of stem wood produced over a rotation. The disc-based wood property models used in this work are based on data with large geographical and genetic variation, and therefore may turn out to be more applicable for predicting future wood and fibre resources at a regional and national level. This kind of integrated use of wood property models with a process-based growth and yield model could help us to evaluate the forest resources under current and changing climate. 相似文献
18.
Katri Luostarinen Katja Hakkarainen Henri Kaksonen 《Scandinavian Journal of Forest Research》2017,32(8):789-797
Soil affects the anatomy of downy birch wood (Betula pubescens), which raises the question whether the growth of this species differs between mineral and peat soils. The aim of this study was to compare growth, density and structure of xylem of B. pubescens between trees grown in different soils. Both growth and density differed between trees grown in different soils. All measured anatomical characteristics, except double thickness of fibre walls, percentage vessel area and ray number, showed differences between the soil types: the cell dimensions were larger and numbers smaller in trees grown in mineral soil. In peat, high growth rates decreased the wall:lumen ratio of fibres in maturing wood, while no such correlation was observed in trees grown in mineral soil at any studied cambial age. In addition, axial parenchyma may have a different role in trees grown in different soils, as the rapid growth decreased and increased axial parenchyma in mineral and peat soil, respectively. The characteristics affecting wood strength were more similar between trees grown in different soils than those affecting water conductance. The observed differences between trees grown in different soils emphasise rapid growth particularly at young ages and shorter reasonable rotation period in mineral soil. 相似文献