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1.
Larix spp.wood is one of the major fast-growing tree species in China,which also has the most forest storage in the northeast of China.Several key properties modification methods and achievements of Larix spp.wood were summarized based on their characteristics.Technology problems of properties modification and new use prospect of modified Larix spp.wood were all discussed. 相似文献
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中国速生泡桐木材品质下降明显,由于速生泡桐木材深加工利用关键技术还没有解决,对其产业发展产生了不利影响,导致高端桐木家具市场出现拒用速生泡桐木材的现象。文中介绍了国内外泡桐资源状况,评述了目前主栽泡桐品系的木材密度、应用价值、色度等指标,指出不同类型市场对泡桐树种、材质的要求。研究分析了国内外泡桐木材市场,重点介绍了引领高端桐木家具的日本与中国、欧美等地区市场差异,在产品品质、制造工艺、桐木质量、密度、纹理、色泽等方面的不同要求;测算了不同区域所占市场份额,即国外占比85%、国内需求占比15%。建议加强我国速生泡桐加工利用研究,同时制定可持续发展对策,培育密度大、白度好、纹理美观的优质泡桐,以期解决低质桐木资源与高端市场需求不相适应的矛盾。 相似文献
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速生材压缩强化处理的工艺与设备进展 总被引：1，自引：0，他引：1
总结了国内外速生材压缩强化处理的研究现状，对速生材压缩强化处理的不同工艺与设备进行了简要介绍。通过对人工林速生材进行强化处理，提高材质，扩大应用范围，从而开辟了适合生产利用的新途径。 相似文献
4.
杨树是我国重要的速生林树种之一。为了充分利用杨树资源,提高速生杨木的品质,缓解我国目前木材的供需矛盾,迫切需要对杨木进行改性处理。论述速生杨木改性的研究进展,目前对速生杨木改性主要是从其材质松软、密度小、硬度低、易腐朽、尺寸稳定性差等天然缺陷出发,采取浸渍处理和非浸渍处理两大主要方式。浸渍改性包括采取有机物浸渍改性、无机物浸渍改性或二者联合浸渍改性。非浸渍改性包括与其它物质或材料复合改性,压密改性,热压改性,高温热处理改性、熏烟热处理改性、汽蒸改性,水热改性以及多种方法联合改性处理。研究表明,这些改性处理方式对杨木材性提高有显著作用,为杨木高附加值生产提供了重要依据。 相似文献
5.
采用南方速生杉木制造指接集成板,从杉木材性、加工工艺、设备性能、材料利用率、生产成本、产品质量和市场需求等方面出发,研究和分析了南方速生杉木制造指接集成板的特点和应掌握的技术问题.结果表明,这种杉木有高胶接强度和浸渍剥离强度,但自身剪切强度较低.采取恰当的工艺与技术,用南方速生杉木可以生产出满足市场需求的较高质量的指接集成板. 相似文献
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采用多元非线性回归方法分析速生阔叶木材的制浆得率与其化学组分、纸浆的抗张指数、撕裂指数分别与纤维形态的相关性,建立速生材制浆性能的预测模型,选取代表性的速生木材进行材性分析和制浆性能试验研究,用实测值与预测模型算出预测值进行对比.结果证明:预测值与实际测定值拟合得很好,预测模型的精度高. 相似文献
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速生菇木树种黧蒴引种试验 总被引：3，自引：0，他引：3
通过4年的引种试验，结果表明，黧萌生长快，菇术产量高，生物量大，直播造林4年生单株平均胸径、树高，冠幅和菇木产量分别为3．7cm、4．0cm、25.和5.2kg,分别是乡土速生菇木树种马桂木、枫香、拟赤杨的1．5～2.2倍、1．3～1．5倍、1．3～2、1倍和4．3～87倍；适应性较强，浅极性，幼苗对环境的抗逆性较弱，生长缓慢，第3年开始表现出速生的特性。适宜在我区低山、丘陵地引种推广。 相似文献
10.
Eka Mulya Alamsyah Liu Chang Nan Masaaki Yamada Kinji Taki Hiroaki Yoshida 《Journal of Wood Science》2007,53(1):40-46
To estimate the potential bonding performance of bonded wood products from tropical fast-growing tree species, a study on
the bondability of Paraserianthes falcataria L. Nielsen, Pinus merkusii Jungh et. De. Vriese, and Acacia mangium Willd from Indonesia was conducted. Two-ply laminations were produced using polyvinyl acetate emulsion (PVAc), urea formaldehyde
(UF), resorcinol formaldehyde (RF), and water-based polymer isocyanate (API) adhesives. In order to determine the bonding
performance, the block-shear test was applied according to the Japanese Agricultural Standard for structural glued laminated
timber under normal conditions and after accelerated-aging treatments. To support this study, the wettability of each wood
species was also investigated through contact-angle measurement. The results showed that the bonding performance of low-density
P. falcataria was better than that of medium-density P. merkusii and medium-density A. mangium, while the bonding performance of medium-density P. merkusii was better than that of medium-density A. mangium. Furthermore, compared with A. mangium, the small contact angle and good wettability in P. falcataria and P. merkusii result in better adhesion and more intimate contact between the wood surfaces and adhesive. 相似文献
11.
刘元 《中南林业科技大学学报(自然科学版)》1990,(2)
本文对乐昌含笑的木材构造和木材物理力学性质进行了研究。结果表明,乐昌含笑生长迅速,树干通直,其木材纹理直,密度小,质软,结构中而均匀,干缩差异小。且具有易干燥、不翘曲、不弯裂等优点,材性类似于杨树。适于作纸浆和胶合板等用材。 相似文献
12.
《Journal of Sustainable Forestry》2013,32(1):41-57
Summary During the 20th century, a sustained afforestation programme was carried out in Scotland, which increased the forest cover from about 4% of the country in 1900 to 17% in 2002. The expansion was achieved primarily through the establishment of evenaged plantations of fast-growing conifer species, most of which were not native to the British Isles. Many of these forests will reach financial maturity in the next two decades, thereby providing a valuable timber resource for the Scottish economy, and giving the opportunity to diversify the forests to meet the multifunctional objectives outlined in the recent Scottish Forestry Strategy. However, diversifying these forests requires the adoption of a range of silvicultural systems and not simply perpetuating the clearfelling and replanting system that has characterized plantation management. These new approaches include greater use of continuous cover forestry and the restoration of native woodlands on sites previously planted with conifers. A sustained period of low timber prices is also influencing this process, as managers are more aware both of the high replanting costs involved in plantation silviculture and of the subsidies given to manage stands for nonmarket benefits. The effect of these changes upon the structure and nature of Scottish forests is unclear, and a sectoral analysis should be undertaken to explore the potential impacts. 相似文献
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广东特色林业的发展现状与对策 总被引：1，自引：4，他引：1
广东省发展特色林业具有得天独厚的条件,针对广东特色林业的发展现状及发展中存在的主要问题,提出了广东特色林业发展的目标任务,即加快发展工业原料速丰林、壮大竹产业、优化经济林品种结构、大力培育花卉产业,并提出了加快立法步伐、加强规范引导,加大扶持力度、拓宽融资渠道等一整套切实可行、较为全面的对策建议. 相似文献
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杨树是很好的速生丰产树种,市场需求较广,有很好的经济价值。可是,我国目前在发展杨树速生丰产林方面还存在着许多困难和问题,今后在生产实践中应该给予重视和解决。 相似文献
15.
林晓辉 《中南林业调查规划》2005,24(4):53-55,58
阐述了林业尤其是速生丰产林产业面临的机遇,福建省发展速生丰产林的优势所在;大型企业暂时观望的主要原因是产权机制没有真正理顺,计划经济下所形成的思维惯性对林权改革造成干扰;强调政府在改革初期的干预,着力解决速生丰产林建设中存在的几个问题;林权改革的目的、意义、原则、任务及实施过程中出现的问题;速生丰产林建设及与之配套的林权制度改革如何加快市场化进程. 相似文献
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Curved laminated veneer lumber (LVL) is manufactured from glue-coated pieces of rotary-cut veneers assembled and pressed between molds. In this study, curved LVLs were produced from two fast-growing wood species such as massion pine (Pinus massoniana Lamb.) and poplar (Populus euramericana CV. I.) for use in furniture. In addition to the applicability of the two wood species used, the optimum technological conditions of curved LVL production with radiofrequency (RF) heating and the physical and mechanical properties of curved LVL were investigated. The results are as follows: (1) Curved LVL made from massion pine and fast-growing poplar shows excellent mechanical properties. These fast-growing wood species are suitable for curved LVL being used as furniture structural members. (2) The mechanical properties of curved LVL are affected by frequency, voltage, RF application time, and moisture content, with the RF application time and moisture content having more important effects on the mechanical properties than the frequency and the voltage. (3) The mechanical properties of curved LVL increase with a linear increase in the density of curved LVL.The abstract of this study was presented at the 9th Annual Meeting of the Chugoku Shikoku Branch of the Japan Wood Research Society, Tottori, October 4, 1997 相似文献
18.
T. Morán-López R. Poyatos P. Llorens S. Sabaté 《European Journal of Forest Research》2014,133(2):369-382
Drought-induced decline is affecting Pinus sylvestris populations in southern Europe, with very little impact on the more drought-tolerant Quercus pubescens. Although multiple studies have investigated interspecific differences in water use and growth strategies, the link between these two processes and how they vary within drought-exposed populations remains poorly understood. Here, we analysed tree ring and sap flow data from P. sylvestris and Q. pubescens stands in the Pyrenees in order to (1) evaluate differences in climate–growth responses among species, (2) disentangle the role of past growth trends and water use strategies in individual trees drought sensitivity and (3) assess whether such intraspecific patterns vary between species. Both species have suffered recent climatic constraints related to increased aridity. However, the effects of past growth trends and current water use traits on drought sensitivity varied among them. Initially, fast-growing ‘drought-sensitive’ pines displayed a higher gas exchange potential but were more sensitive to evaporative demand and soil moisture. They also showed lower water use efficiency for growth (WUEBAI) and current growth decline. In contrast, initially, slow-growing ‘drought-tolerant’ pines showed the opposite water use traits and currently maintain the highest growth rates. In comparison, neither current WUEBAI nor recent growth trends varied across Q. pubescens climate–growth groups. Nonetheless, ‘drought-sensitive’ oaks showed the lowest gas exchange potential and the highest growth rates under milder conditions. Our results show a strong effect of past growth trends and current water use strategies on tree resilience to increased aridity, which is more evident in P. sylvestris. 相似文献
19.
The initial introduction of Pinus elliottii (PEE) to China occurred in the 1930s, and the planting of this conifer species has now attained close to 3 million ha in the subtropical zone of southern China. A large-scale genetic improvement program for PEE was implemented in southern China to produce fast-growing trees with high wood quality to address the severe shortage of timber production over the last two decades. In this paper, selection for stem volume, basic wood density (DEN) and modulus of elasticity (MOE) was based on the Smith–Hazel index, and a total of approximately 2 000 individual trees from 158 PEE open-pollinated families were selected at 22 years of age. The DEN and MOE for each tree were determined by non-destructive evaluation techniques using the Pilodyn and Hitman Director ST300® acoustic velocity device. The heritabilities and genetic and phenotypic correlations for the traits that were measured were estimated using the residual maximum likelihood approach in the flexible mixed modelling program ASReml-R. The results showed that the heritability estimates for the wood properties were between 0.292 and 0.309, and the heritabilities of the growth traits ranged from 0.129 to 0.216. The genetic correlation between the DENP and acoustic velocity (V?) with MOEP was 0.45 and 0.95, respectively. An indirect selection based on V was observed to be highly effective for determination of MOE. It indicated that V can be integrated into tree improvement programs as a useful index of MOE by ranking candidate families or individuals within the selection population. The genetic correlations between the growth traits and wood properties were not significant. By contrast, the phenotypic correlations between them were significantly positive, but the correlation coefficients were very low. The appropriate selection index (I4), which placed 10 times as much weight on DEN and MOE as the equal emphsis method, was determined as the appropriate selection index. 相似文献
20.
黑杨纸浆材品种的材性遗传分析和选择 总被引：3，自引：0，他引：3
作者选用当前推广的和经１次生长初选的速生黑杨无性系为试验材料，以纸浆材品种选择为目的，进行了木材性状和生长性状的遗传分析，并运用综合选择指数从中筛选出生长、材性具佳的Ｃａｒｐｐａｃｃｉｏ、９２５、Ｉ－６９、８０－Ｉ－６和鲁伊莎等５个优良无性系。可作为纸浆工业用材林品种进行区域推广。 相似文献