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《濒危野生动植物种国际贸易公约》简称CITES公约。2013年3月,CITES公约缔约国在泰国曼谷召开了第十六届缔约国大会,会议期间讨论了各缔约国提交的对《公约》附录所列物种进行修订的提案,通过的CITES公约管制物种附录有了最新调整。本刊针对这次CITES公约的调整采访了中国林业产业联合会副秘书长、中国林产工业协会秘书长石峰,就《濒危野生动植物种国际贸易公约》(以下简称 相似文献
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柞树是辽东山区的主要阔叶用材树种,在天然次生林的分布中,柞树占据的面积较大,并以蒙古栎和辽东栎为多。为了充分利用该树种的经济价值,对其成熟龄进行初步研究。结果表明：柞树的数量成熟和经济成熟期,均在50年左右;工艺成熟,小径原木和车辕材55年时进入工艺成熟期,一般原木80年后才到来;柞树55年时开始心腐,随年龄增长会逐渐加重.初步认为萌生柞树的主伐龄为50年。 相似文献
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《Forest Policy and Economics》2008,10(6):400-407
The FIA BioSum model was used to simulate three fire-hazard-reduction policies in an area comprising northern California, southwestern Oregon, and the east slopes of the Cascade Mountains in Oregon. The policy scenarios, all subject to a stand-scale fire-hazard-reduction effectiveness constraint, included maximize torching index improvement (Max TI), maximize net revenue recovery (Max NR), and minimize merchantable timber removal (Min Merch). Differences in the area treated under each scenario were considerable, ranging from 15 to 96% of the area for which effective treatments are technically feasible. For each scenario, weight, species, and source tree size of both dirty chips (hogfuel or biomass) and saw logs were estimated. The mix of species and sizes removed under each scenario was surprisingly similar, although the Min Merch scenario did remove more noncommercial species such as hardwoods and more saw logs in the midsize classes (10 to 16in. diameter at breast height (dbh); 25.4 to 40.6cm) than the other two scenarios. Saw logs accounted for 67 to 79% of the weight removed. Under all scenarios, the Douglas-fir (Pseudotsuga menziesii)/larch (Larix) and white woods (Picea spp., Tsuga spp, and Abies spp.) species groups accounted for nearly all of the saw logs removed. Tops and limbs of commercial species and noncommercial species accounted for most of the dirty chips. Stems of low value commercial conifers (7 to 16in; 17.8 to 40.6cm) were also an important source of dirty chips. Trees smaller than 7in. (17.8cm) dbh were a relatively minor component of the dirty chip mix. 相似文献
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This paper reports findings of surveys into small-scale sawmilling and timber processing in Phu Tho Province and the Tam Dao
National Park buffer zone in northern Vietnam. The objective of these surveys was to examine the extent to which small sawmills
and timber processors utilise farm-grown timber, so as to explore the prospects for expansion of farm-grown timber markets.
The operational scope, supply chain and value chain of the industry are reported. Resource availability and current and future
perspectives are discussed. Timber prices were found to vary greatly between species and study areas. Species most in demand
by enterprises are Artocarpus heterophyllus, Melia azedarach, Manglietia conifera, Acacia spp., Chukrasia tabularis and Erythrophloeum fordii. Small-scale sawmilling and timber processing activities fit well with rural communities in Vietnam and have potential for
further development if current constraints can be overcome. Further tree planting is needed to meet the presently unsatisfied
timber demand and to create income and employment. Information from sawmillers and timber processors suggests the types of
species that farmers should be considering for their plantings. 相似文献
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木材防腐技术在山海关镇东楼木结构中的应用 总被引：2，自引：2，他引：0
针对山海关镇东楼木腐菌及木材害虫种类,采用多种药剂及处理方法,对木材进行防腐处理。经鉴定主要木构件树种为硬木松、软木松、落叶松和云棚类木材。防腐处理后的木材经验测其力学强度无明显变化。采用强制气干法干燥木材,简便易行。 相似文献
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This study assessed the sustainability of selection cutting in a community forest (CF) in Bhutan. The harvesting approach differed from cable crane logging operations in an adjacent commercially managed forest by creating much smaller canopy openings. This had many implications for natural regeneration of preferred species. The study was conducted in a late successional broadleaved CF containing 32 genera of tree species dominated by Quercus and Castanopsis and managed for timber, firewood, non-wood forest products and forest grazing. The study was based on a comparison of two forest inventories to assess forest structure and regeneration, a study of stumps to quantify harvesting intensities, and a household survey to quantify livestock holdings and grazing patterns. The study examined different intensities of selection cutting in three blocks of the CF and found that higher intensities of selection cutting did not have a negative impact on: (a) natural regeneration of seedlings and saplings of preferred timber species; (b) the diameter distribution of all species and use categories except for Quercus; (c) the diversity of tree genera; and (d) the percentage of remaining trees with favorable bole shape and form. These results contrasted with findings in the adjacent commercially managed forest. Community management of broadleaved forests with selection cutting appeared to be sustainable and avoid some of the unresolved silvicultural problems associated with commercially managed forests in Bhutan. However more research is needed on the sustainable management of Quercus spp. 相似文献
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This paper presents a case of planting and management of natural regeneration of shihuahuaco (Dipteryx spp.) by recent migrants in a Peruvian Amazonian logging frontier. We interviewed residents of three communities of smallholders in Irazola District, Province of Padre Abad, Region of Ucayali, located within the historic and actual boundaries of an active logging concession, and conducted growth studies of shihuahuaco trees planted in two mixed-species agroforestry fields, over a period of 3 years. We found that the majority of landholders were managing the natural regeneration of valuable hardwood timber trees, and planting seedlings on their lands. Growth of shihuahuaco trees in agroforestry fields was comparable to growth rates in managed silvicultural plantations, which suggests the potential for local smallholders activities to contribute to conservation of genetic stock and eventual renewal of populations depleted by logging. We recommend greater recognition and inclusion of local people, with their innovative and productive silvicultural practices, in efforts to remediate the impacts of selective logging of high-value timber species. 相似文献
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各树种的生物学特性各不一致,对环境的适应性存有差异。为此,自1978年开始,有目的地对一些珍稀、优良用材树种在杭州地区不同类型立地上进行试种,了解各树种较适宜的环境条件,以期为不同立地选择栽培树种提供依据。 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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Do multipurpose companion trees affect high value timber trees in a silvopastoral plantation system?
Establishment of native timber trees on deforested land may contribute to the livelihood of farmers, to improved ecosystem
services and to increased greenhouse gas uptake. Here, we present a new silvopastoral planting design to assess species performance
and interspecific competition or facilitation effects among native timber and multipurpose trees in Central America. Two timber
species, Tabebuia rosea and Cedrela odorata, were established in three low-density planting regimes allowing combined tree and future livestock production: (1) solitary
planting, (2) companion planting with Guazuma ulmifolia, and (3) companion planting with the nitrogen-fixing Gliricidia sepium. We quantified survival, growth and reforestation potential of the two timber species subjected to the different planting
regimes for the first 2 years after establishment. Nitrogen concentration as well as stable nitrogen and carbon isotope composition
(δ15N, δ13C) of leaves of the timber saplings were determined. T. rosea showed higher survival and better growth than C. odorata under varying environmental conditions (soil, concomitant vegetation). Performance of the timber saplings was unaffected
by either companion species. Planting regimes had no effect on foliar nitrogen concentration and δ15N of the two timber species, although δ15N values indicated nitrogen fixation activity in G. sepium trees. Planting regimes affected foliar δ13C values in T. rosea. δ13C values were significantly higher in solitarily growing individuals, suggesting lower exposition to water stress conditions
in saplings surrounded by companion species. As we found positively correlated growth traits among timber and multipurpose
trees, a combined planting may benefit farmers by providing additional goods and services. 相似文献