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XIONG Manzhen BAO Fucheng Research Institute of Wood Industry Chinese Academy of Forestry Beijing P. R. China 《中国林业科技(英文版)》2005,4(4):84-91
INTRODUCTION Because China is deficient in forest resources, and the forest has the characteristics of low quality, uneven distribution, slow growth and severe situation of ecological environment, the ecology construction has become the first requirement in society and with the implementation of the “Natural Forest Conservation Program”, Chinese forestry is in the historic transition from timber production to ecological construction. Therefore, the timber production in China increases… 相似文献
73.
不同水性高分子异氰酸酯胶对人工林木材胶合性能的影响 总被引:2,自引:0,他引:2
采用同一类型的高分子化合物、填料和乳胶按不同配比组成2种主剂,然后与贮存期不等的交联剂组成不同的水性高分子异氰酸酯胶黏剂(API),用来黏接杉木、杨木、巨桉、尾巨桉、柠檬桉和窿缘桉等6种人工林木材试样以研究 API主剂特征和交联剂贮存时间对人工林木材胶合性能的影响。试验结果表明:1)API主剂特征显著影响6种人工林木材的胶合性能。2)随着交联剂贮存期的增长,人工林试材的胶合性能有降低趋势,但胶合杉木、杨树、巨桉和尾巨桉4 种人工林木材时仍能达到标准要求。 相似文献
74.
陈茜文 《中南林业科技大学学报(自然科学版)》1995,(2)
采用我国木材化学成分分析国家标准,对湖南40种主要树种木材的化学成分组成进行了分析测定.并结合各树种木材的化学成分及其性质,对其在工业方面的开发利用进行了探讨.所测得的数据,可供各地开发利用各种木材作为参考. 相似文献
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Current silvicultural treatments in beech forests are aimed at achieving thick logs without discoloured hardwood. Therefore
intensive thinning is applied already in younger stands with the objective of large-sized trunks at an age of 100 years. However,
this approach bears the risk that dead wood structures and broken trees are completely removed from the forest. The impact
of three different silvicultural management intensity levels on wood-inhabiting fungi over decades was investigated in a large
beech forest (>10,000 ha) in southern Germany in 69 sampling plots: A Intensive Thinning and Logging with high-value trees,
B Conservation-Oriented Logging with integration of special structures such as dead wood and broken trees and C Strict Forest
Reserves with no logging for 30 years. The analysis of community showed marked differences in the fungus species composition
of the three treatments, independent of stand age. The relative frequencies of species between treatments were statistically
different. Indicator species for naturalness were more abundant at sites with low silvicultural management intensity. Fomes fomentarius, the most common fungus in virgin forests and strict forest reserves, is almost missing in forests with high-management intensity.
The species richness seemed to be lower where intensive thinning was applied (P = 0.051). Species characteristic for coarse woody debris were associated to low management intensity, whereas species with
a significant preference for stumps became more frequent with increasing management intensity. A total amount of dead wood
higher than 60 m3/ha was found to enable significantly higher numbers of species indicators of naturalness (P = 0.013). In conclusion, when applying intensive silvicultural treatment, the role of dead wood needs to be actively considered
in order to maintain the natural biocoenosis of beech forests. 相似文献
77.
《中国林业科技(英文版)》2009,(2)
As an emerging industry,China's wood floor industry dates back to the early 1980s. Despite a late start,it has developed rapidly during the last 20 years.The past decades have witnessed great changes in China's wood floor industry.With high quality,many products"made in China"are available widely abroad nowadays.Current global economic shocks,however,affect China's domestic real estate sector;hence the falling domestic sales of wood floor.The paper aims to identify the current situation of floor industry... 相似文献
78.
Tekat Dwi Cahyono Wayan Darmawan Eka Novriyanti 《Wood material science & engineering》2020,15(3):155-162
ABSTRACTA study to determine the quality of laminated veneer lumber (LVL) from samama wood (Anthocephalus macrophyllus) was carried out. Samama is a fast-growing endemic wood in eastern Indonesia. Factorial of three factors in RAL design was used to investigate the influence of veneer thickness, juvenile proportion and veneer lay-up to the quality of the resulted samama LVL. The veneer thicknesses were 1.5 and 3.0?mm. Juvenile proportions were arranged in five levels, which were 100% of juvenile veneer, 100% of mature veneer and combination of both juvenile and mature with juvenile proportion of 14%, 43% and 71%. Two veneer lay-up used in this study were loose side met loose side and tight side met loose side. The result of the study showed various specific gravity of LVL by different proportions of juvenile. This factor also affected the other physical traits. Shear strength of the LVL was equal to the solid wood, yet MOE and MOR were affected by juvenile proportion and veneer lay-up. LVL developed from 100% of mature veneer exhibited the highest MOE and MOR, yet no significant difference was noted in MOE and MOR between LVL 100% of juvenile and other tested juvenile proportions. 相似文献
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