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对人工林木材材质的研究是一个热点,木材的材质直接影响到加工利用,思茅松、巨桉、龙竹和西南桦是我省主要的人工林树种。本文综述云南木竹材(思茅松、巨桉、龙竹和西南桦)的研究现状,培育措施(包括不同造林密度、抚育间伐)和立地条件对木材材质的影响,并指出纤维形态、综纤维素、木质素、戊聚糖、1%NaOH抽出物、苯醇抽出物、生长轮宽度、晚材率、基本密度等影响纸浆材材质的主要性能指标。 相似文献
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热带速生珍贵紫檀属树种 总被引:4,自引:0,他引:4
系统介绍世界范围内紫檀属树种的种娄、分布、生长特性,人工林营造术材性质与加工利用.非木质林产品利用等。蝶形花科紫檀属分布于世界热带地区多为速生珍贵树种其材质优良.属红大之列,为世界名材。我国已有部分栽培,并对引种前景进行评述。 相似文献
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桦木人造装饰单板制造工艺的研究 总被引:1,自引:0,他引:1
1 桦树资源状况及材性特点桦树是黑龙江省主要用材树种之一 ,其蓄积量占小兴安岭森林资源的 40 %。因此研究桦木的有效利用途径 ,对黑龙江省森林资源的合理开发具有重要意义。桦木属重硬材 ,不耐腐并具有干状脆性 ,早晚材颜色区别不明显 ,质地密实 ,较细腻。但白桦的边材呈白色 ,芯材呈红褐色 ,边芯材色差较明显 ,这些影响了它的使用范围 ,造成资源浪费。因此在对桦木进行加工利用前 ,需要进行相应的单板前期处理 ,以改善其色差和材质 ,同时减少其脆性 ,改善单板的加工性能。2 单板的前期处理2 .1 材料与方法选取 0 .7~ 1.1mm厚的桦木单… 相似文献
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综合利用木材剩余物值得注意的几个问题 总被引:1,自引:0,他引:1
木材剩余物,它包括采伐后的枝丫、树梢、树皮、树叶、树根及藤条灌木的采伐剩余物;制材截头的剩余物;加工后的板皮、板条、木竹截头、锯沫、碎单板、木芯刨花、木块边角余料的加工剩余物;材质低于针阔叶树加工原木最低等级但具有一定利用价值的次加工材,长度在2米以下或径级8厘米以下的小原木、松木干、杂木干、短原木的小径材和薪材等。 相似文献
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陕西兰考泡桐木材构造和材性的研究 总被引:3,自引:0,他引:3
对陕西渭南产兰考泡桐木材构造和材性的研究表明,木材材质优良,利用价值与其它泡桐相当,其管孔式类型并非为单纯的环孔材或单纯的半环孔材,而是环孔材至半环孔材。 相似文献
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以胸径、树高、材积为数量评价指标,结合干形、冠高比和分枝粗细形质指标,采用5株优势木对比法开展了西南桦人工林的优树选择技术研究。通过对西南桦人工林10 21年生不同林龄阶段的优树选择标准的总结,提出了优树选择标准,即优树胸径、树高、单株材积分别大于5株对比优势木平均值的9%11%、5%7%、26%31%以上,形质指标综合得分大于7.5,共选择出西南桦优树37株,入选率为33.9%。西南桦优树的选择标准在实际应用中可根据林分状况适当调整,选优即要考虑其生长性状,同时注意材性、抗性的选择以保证西南桦育种群体的遗传多样性。 相似文献
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Shaopeng Yin Zhenhai Xiao Guohui Zhao Xin Zhao Xiaoyang Sun Ying Zhang Fuwei Wang Shuchun Li Xiyang Zhao Guan-Zheng Qu 《林业研究》2017,28(4):687-697
The growth traits (tree height, diameter at breast height, and stem straightness degree) and wood properties [wood density (WD), fiber length, fiber width, ash content (AC), lignin content, cellulose content, hemicellulose content (HEC), and holocellulose content] of 208 26-year-old Larix olgensis clones were analyzed. Except for WD and AC, there were significant differences (p < 0.01) for all traits among clones. The phenotypic coefficient of variation and repeatability of all traits were 9.34–35.33% and 0.218–0.930, respectively. Tree height and diameter at breast height showed significant positive correlation; however, the correlation coefficients among growth characteristics and wood properties were mostly not significant. Ten clones (L70, L56, L82, L90, L59, L91, L61, L92, L86, and L64) were selected as excellent clones under a selection rate of 5%, using tree height, diameter at breast height, and stem straightness degree as evaluation indexes, providing genetic gains of 28.69, 17.96, and 0.67%, respectively. Ten clones (L88, L305, L59, L66, L253, L304, L277, L298, L248, and L293) were selected as excellent clones using wood properties as an evaluation index, with a selection rate of 5%, providing genetic gains in WD, fiber length, fiber width, cellulose content, and HEC of 4.14, 3.64, 9.28, 6.77, and 9.61%, respectively. This study provides a theoretical basis for selecting excellent L. olgensis clones. 相似文献
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在福建省洋口国有林场,对来自安徽省南部黄山地区的53个枫香家系进行子代测定,研究家系的遗传变异规律,开展优良家系及单株选择.结果表明:子代试验林14年生时,树高、胸径和单株材积平均值分别为8.05m、6.30cm和0.014 93 m3,生长性状的家系遗传力为0.437~0.576,受中强度的遗传控制,单株遗传力为D.113~0.195,受较弱的遗传控制;木材材性的家系遗传力为0.507~ 0.591,单株遗传力为0.360~0.500,均受中强度的遗传控制.以生长量为主要指标,选出速生优良家系9个,其树高、胸径和单株材积平均值分别为8.85 m、7.22 cm和0.021 49 m3,遗传增益分别为2.86%、5.47%和13.4%;从木材基本密度大于0.500 g·m-3的家系中选出7个生长材性兼优家系,树高、胸径、单株材积和木材基本密度的平均值分别为8.34m、6.79 cm、0.018 58 m3和0.518 g·m-3.所选出的速生优良家系和生长材性兼优家系可作为枫香育种材料在生产上推广应用. 相似文献
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Calycophyllum spruceanum (Benth.) Hook. f. ex K. Shum. is an important timber-tree species in the Peruvian Amazon Basin. Markets currently prefer
wood with a uniform, light yellow color, but these preferences may change in the future. As farmers and industry commonly
use wood from young trees, it is important to investigate genetic and environmental variation in juvenile-wood properties
to assess whether tree improvement programs could make adjustments to changing preferences. A provenance/progeny test was
established to evaluate genetic variation in growth and wood properties of young trees, the strength of their genetic control
as well as their interrelationships both at the genetic and the phenotypic level in different planting zones. This paper presents
analyses of variation in wood color at 39 months, and their correlations with tree growth and wood basic density. CIELab means
for lightness ranging from black to white (L), green to red hues (a*) and blue to yellow hues (b*) were 67.63, 5.34 and 22.12,
respectively; means for chroma (C) and hue angle (h)* were 22.76 and 76.43, respectively (C and h* were estimated from a*
and b*). Significant variation due to provenances and especially due to families within provenances was found in some wood
color characteristics, and some color characteristics also differed significantly among planting zones. Genetic correlations
indicate that, in general, selection of faster growing trees and/or trees with denser wood would have little effect on wood
color and its uniformity. In general, wood color had relatively low heritability (h
i
2): among all trees, h
i
2 = 0.31 for L; and variance due to families was not significant for a* and b*. Genetic control of color was highest in the
planting zone where trees grew most rapidly: h
i
2 = 0.48 and 0.52 for a* and b*, respectively; but variance due to families was not significant for L. Results suggest that
selection based on wood color would be more effective in zones with more fertile soils and higher rainfall.
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A study of material thinned from a 9-year-old Eucalyptus dunnii progeny trial revealed that E. dunnii has light yellowish wood that is relatively uniform in color, and varies little within and between trees. The variation in
color between half-sib families is small, but is statistically significant (P = 0.008). Most of the color variation relates to the yellowness (CIE b*) of the wood, which in heartwood is moderately heritable (h = 0.6). The color of the endgrain, especially its lightness (CIE L*) and whiteness index (E313), is correlated with basic density, hardness, and rates of shrinkage. The CIE rectangular opponent
scale (L*, a*, b*) appeared to be the most informative about wood color and properties, and no additional information was gleaned from an
analysis of full spectral data in the range 400–700 nm. 相似文献
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针对福建建瓯的7年生33个产地的木荷种源试验林,研究揭示其生长和木材基本密度的种源差异及地理变异模式,并依据聚类分析结果进行速生优质种源选择。结果表明,木荷胸径、树高、枝下高、材积指数和木材基本密度等存在显著或极显著的种源变异,其中以材积指数的种源变异最大。木荷生长和木材基本密度的种源变异主要受产地温度影响,呈典型的纬向变异模式,来自纬度较低、温度较高产地的木荷种源,其树高、胸径和材积指数等生长量较大,木材基本密度较小。木荷各性状间也存在相关性,其木材基本密度与生长性状呈显著负相关。除存在显著的种源效应外,不同重复间的微立地效应也非常显著,在较差立地条件下,木荷种源的生长量较小,但木材基本密度呈现增大趋势。基于生长和木材基本密度进行种源聚类,可大致将木荷划分为中心种源区、中部种源区和北部种源区3个种源区。同时,以高于材积指数和木材基本密度种源总体均值为选择标准,分别初选出17个速生型和11个速生优质型木荷优良种源,其中多数优良种源来源于南岭山脉—武夷山脉的中心种源区。 相似文献
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为了分阶段测定油松自由授粉家系间差异和选择油松优良家系,对82个油松家系(22年生)进行生长性状的遗传变异分析,分析树高和胸径的年-年遗传相关、表型相关及历年的遗传方差和环境方差、遗传及表型变异系数、遗传力的同时,研究不同林龄树高和胸径与22年生时材积的相关关系。结果表明:油松家系间树高、材积等生长存在极显著差异。结合早期选择效率和选择正确率及去劣错误率,认为油松优良家系选择是可以在早期进行的,其初选年龄应是9年生时。此外,在22年生时以材积育种值为选择指标,筛选出24个油松优良家系,其单株材积实际增益分别较对照28、95和106增加了36.54%、8.92%和18.63%。最终选出速生优良家系和二代优树 61株,子代测定林入选二代优树的材积遗传增益分别较对照28、95和106增加了57.74%、25.81%和37.03%。所选出的优良家系和优良单株可作为油松育种材料在生产上推广应用。 相似文献