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Portable sawmilling trials with Acacia aneura (mulga) and A. cambagei (gidgee) have been undertaken to estimate the private landholder costs associated with small-scale timber production from
woodlands in western Queensland, Australia. A time study of harvesting and milling operations facilitated estimation of landholder
labour input requirements. The scarcity and small size of millable logs, coupled with the prevalence of timber defects, make
harvesting and portable sawmilling of western Queensland acacias an expensive undertaking for landholders. The cost of producing
sawn timber that meets the High Feature (HF) grade of Australian Standard AS2796 is estimated at between A$3,000/m3 and A$3,400/m3 of HF timber. 相似文献
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Anita Firmanti Efendi Tri Bachtiar Surjono Surjokusumo Kohei Komatsu Shuichi Kawai 《Journal of Wood Science》2005,51(4):339-347
Some reports have shown that for single species the correlation between modulus of elasticity (MOE) and modulus of rupture (MOR) in bending is quite high. Tropical timbers consist of hundreds of species that are difficult to identify. This report deals with the mechanical stress grading of tropical timber regardless of species. Nine timber species or groups of species with a total number of 1094 pieces measuring 60 × 120 × 3000 mm, were tested in static bending. The MOE was measured flat wise, while MOR was tested edge wise. Statistical analysis of linear regression with a dummy model and analysis of covariance were used to analyze the role of MOE and the effect of species on prediction of MOR. The analysis showed that using MOE as a single predictor caused under/overestimation for one or more species and/or groups of species. The accuracy of prediction would be increased with species identification. An allowable stress and reference resistance for species and/or groups of species were provided to compare with the prediction of strength through timber grading. The timber strength class for species and/or groups of species was also established to support the application of mechanical timber grading. 相似文献
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珍稀及待开发树种材性及用途的研究 总被引：5，自引：2，他引：5
选择了大别山五针松、杉松、三角枫、山核桃,梓树、朴树、连香树、毛,丝棉木,刺揪,铜钱树,棠梨、琅琊榆,醉翁榆及榔榆等１５个树种,观察和记载木材解剖特征,分析其化学成分,测试物理性质,力学性质以及加工性质。根据上述各树种的材质、材性和加工性质,大别山五针松、山核桃、梓树、连香树,琅琊榆,醉翁榆及榔榆等木材优良,应属于稀有和珍贵的木材树种。杉松、三角枫、朴树、毛、丝棉木、刺揪、铜钱树及棠梨等木材质量好,价值高,可以有计划的发展作为重要的商品材开发利用。本文还根据各树种木材的特性,结合实际调查,提出这些树种木材的合理加工和利用的意见。 相似文献
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The Community Rainforest Reforestation Program (CRRP) in north Queensland, Australia, was a multi-faceted experiment in facilitating
farm forestry. It was motivated in part by the World Heritage listing of the Wet Tropics of Queensland rainforests, which
removed a large resource from the timber industry. Survey results indicate that some landholders have applied high-quality
silvicultural management to their stands with a view to timber production, while others have been more interested in wildlife
habitat and other non-wood benefits. Although not necessarily a success in terms of its stated goals, the program can be credited
with a number of achievements. It yielded valuable experience in growing native tree species, job training for young unemployed
people, and collaboration between Federal, State and local government in forest industry development. The program generated
positive environmental outcomes and lessons for future timber and environmental planting programs on private lands. While
the area planted and quantity of timber produced will fall far short of initial expectations, and some limitations arose with
the job training activities, it nevertheless appears to have been a worthwhile project. 相似文献
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This paper reviews the findings of nine studies carried out over about the last decade by a forestry socio-economic research
group in Queensland, Australia. On the basis of survey evidence and landholder typology research, the questions of who plants
trees and for what reasons are addressed, and inferences are drawn about the impact of land fragmentation on farm forestry.
It is concluded that forestry is less popular on the larger and commercially viable farms than on smaller holdings of similar
land type, and plantation establishment is often supported by off-farm income, so that farm fragmentation may actually lead
to increased tree planting. However, whether this would lead to increased timber production is less clear, because of the
strong interest of people on small holdings in environmental plantings and because of difficulties in marketing small quantities
of the variable quality timber from mixed-species plantings. Also, the quality of silviculture appears to be positively correlated
with area planted. Some implications are drawn for land-use policy. 相似文献
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余颖 《林业机械与木工设备》2009,37(6):27-29
在直燃用小径材采收和加工过程中，收割和削片技术装备十分关键。以北方常见直燃用小径材为研究对象进行切削功耗研究，分析其树种、径级及含水率等因素对切碎能耗的影响，为能源林联合收获机及其他加工设备的研发提供技术参考依据。 相似文献
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张羽 《内蒙古林业调查设计》2008,31(3):48-51
在永安市巨桉(Eucalyptus Garndis)林分选择并设置10个标准地,分别进行林分因子调查,以4m段材长分径阶进行样木伐倒造材,应用区分求积式进行材积计算,以实际造材各材种出材率为基础拟合一元材积比方程,根据相关系选择较优的一元材积比方程进行理论造材并编制巨桉林分一元材种出材率表,并进行精度检验,表明精度可达90%以上,可为桉树生产提供一定的参考。 相似文献
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赣南林业生物质能源林建设情况调研报告 总被引：1，自引：0，他引：1
对赣州市生物质能源林建设情况进行初步调查,分析生物质能源林基地发展现状,提出生物质能源林发展存在的问题和对策建议. 相似文献
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Yuliati Indrayani Tsuyoshi Yoshimura Yoshiyuki Yanase Yuji Imamura 《Journal of Wood Science》2007,53(3):239-248
Five Japanese timbers, four timbers from the USA, and one Malaysian timber were evaluated for their resistance to the invasive
dry-wood termite Incisitermes minor (Hagen) using laboratory choice and no-choice feeding tests with holed specimens. The highest survival rates of I. minor in both the heartwood and sapwood no-choice feeding tests were more than 70% after 3 months. When offered sapwood and heartwood
choice feeding tests and the combined choice feeding tests, the highest survival rates of I. minor were more than 75% after 3 months. With regards to the percentage of wood mass losses in the no-choice and choice feeding
tests, karamatsu (Larix leptolepsis), buna (Fagus crenata), and Douglas fir (Pseudotsuga menziesii) were classified as “resistant” species among the ten sapwood specimens. In the heartwood no-choice and choice feeding tests,
the resistant species were buna, karamatsu, Douglas fir, sugi (Cryptomeria japonica), akamatsu (Pinus densiflora), and western red cedar (Thuja plicata). The ranking of the resistance of the ten commercial timbers against I. minor was buna > karamatsu > sugi > western red cedar > Douglas fir > rubber > western hemlock > hinoki > spruce. 相似文献
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