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1.
Small volumes of timber from Acacia and Eucalyptus woodlands of western Queensland, Australia, have achieved high prices in specialty timber markets, which has aroused the
interest of landholders. A postal survey of 225 domestic and international specialty timber product manufacturers was undertaken
to determine current utilisation of these lesser-known species, establish their suitability for various product markets, ascertain
desirable timber dimensions and condition, and estimate potential future domestic and international demand. An overall response
rate of 31% was achieved. Responses indicated that current utilisation of these timbers is probably not more than 200 m3/yr. Nevertheless, respondents generally indicated that western Queensland hardwoods are highly suited to the manufacture
of specialty timber products, including small-scale furniture items, custom knife handles and musical instruments, and that
they have high export potential. Some furniture and musical instrument manufacturers indicated they would be willing to pay
up to $3,000/m3 and $30,000/m3 respectively, for small volumes of high-quality appropriately processed western hardwoods. Large, well-directed marketing
campaigns will be necessary to expand specialty timber markets for western Queensland hardwoods. 相似文献
2.
M. Bertomeu 《Small-Scale Forestry》2006,5(1):57-81
In the Philippines, timber production on small farms has become profitable as a result of reduced supplies due to extensive
deforestation and increasing demand. In the early 1990s, when the price of timber was high, farmers were promised huge returns
from tree farming. However, widespread planting of few species has led to oversupply and a sharp decline in the price of farm-grown
timber. Moreover, low intercrop yields as a result of competition from fast-growing trees and low timber yields due to poor
tree management, further reduce net economic returns. In spite of this, interest in tree farming remains high. This paper
examines the private profitability of two tree-maize systems, namely trees in blocks and trees in hedgerows, compared with the alternative of maize monocropping. The analysis reveals that maize monocropping provides higher returns
to land at the current timber price, but considerably lower returns to labour, than the maize-tree systems tested. This suggests
that tree farming is a more attractive option for labour and capital-constrained households or those with off-farm opportunities
that compete for their labour. These farmers may raise productivity and income by planting trees on the excess land that cannot
be devoted to annual crops. The analysis also indicates that wide-spaced tree hedgerows are superior to tree blocks, due to
lower establishment and management costs, longer periods of viable intercropping and more rapid tree growth. 相似文献
3.
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
4.
Carolin Fischer Olav A. Høibø Geir I. Vestøl Marius Hauglin Endre H. Hansen Terje Gobakken 《Scandinavian Journal of Forest Research》2018,33(6):603-612
Norway spruce structural timber is one of the most important products of the Norwegian sawmilling industry, and a high grade-yield of structural timber is therefore important for the economic yield. Presorting of logs suited for production of structural timber might be one option to increase the grade yield. In this study, dynamic modulus of elasticity (Edyn) of structural timber was predicted based on forest inventory data at site level and single-tree data from airborne laser scanning (ALS) and harvester. The models were based on 611 boards from 4 sites in southeastern Norway. Important variables at site level were elevation, site index (SI), and mean stand age. However, when combining data from all information sources, mean stand age and site index were the only significant variables at site level. Tree height and variables describing the crown, like crown length and crown volume, were important vaiables extracted from ALS data. Stem diameter measures and tapering were important variables measured by the harvester. The combined model with variables from all three information sources reduced the variance the most, especially when using individual tree age instead of average stand age. However, combining all these data requires accurate positioning of the trees by the harvester. 相似文献
5.
中国木材进口需求材种结构数量关系分析 总被引：1，自引：0，他引：1
文中采用近乎理想的需求系统模型,分析中国木材进口需求的结构性特征及各材种之间的经济学关系。研究发现:进口针叶材的支出弹性明显高于阔叶材,说明进口木材消费规模的扩大将在更大程度上带动针叶材需求;针叶锯材进口需求富有弹性而其他商品进口需求缺乏弹性,尤其是阔叶原木进口需求曲线最为陡峭;不同材种之间的交叉价格弹性为负值,同一材种之间的交叉价格弹性为正值,说明不同材种之间为互补品,而同一材种之间为替代品;粗加工产品进口价格的上涨会引发深加工产品进口量的上升,如果再加上旺盛的进口需求,这一效果将更为明显。 相似文献
6.
Households and wood processing businesses in the provinces of Son La, Dien Bien and Lai Chau in the Northwest of Vietnam were surveyed to determine patterns of local wood demand and supply, changes in species utilized over time, and whether timber from planted trees might substitute for species previously harvested from local natural forests. In each province, 5–6 sawmills and 4–6 villages representing 3 main ethnic groups were selected for investigation. Managers of selected sawmills and 3–4 randomly selected households in each village were interviewed using semi-structured questionnaires. There was high and uniform household demand for fuelwood in the surveyed villages, making fuelwood the dominant use, in terms of wood volume. Use of sawn timber for furniture, home repair and construction consumed less wood but required logs of acceptable species. Sawmills surveyed were small, with input capacity ranging from <15 to 500 m3 of logs per year, suggesting a total log requirement of about 30,000 m3/year for the 192 known wood processing businesses in the three provinces. Most sawmills still used wood from natural forests, sourced locally or imported from Laos. A trend of switching from prized timber species from natural forests, now effectively unavailable, to alternatives from natural and planted forests was reported by both sawmills and households. Some planted species grown on short-medium rotations appear able to substitute for local sawn timber requirements. 相似文献
7.
Rahman M. Motiur Jiro Tsukamoto Yasushi Furukawa Zenichiro Shibayama Isao Kawata 《Journal of Forest Research》2005,10(4):285-294
This study determined existing quantitative stand structure and its implication on silvicultural management of homestead forestry. The results showed that fruit and timber species have importance values of 57% and 43%, respectively, in the study area, which is in contrast to the commonly held view of absolute domination of fruit species. The fruit species were only moderately dominant over timber species in relation to the quantitative stand structure of homestead forests. Two fruit species, Mangifera indica and Artocarpus heterophyllus, contribute about one third of the stand structure, while amongst the timber species Samanea saman and Albizia spp. are the most important species. A simulated evaluation of soil expectation value of homestead forest showed that the existing stand structure would not maximize the financial gain perpetually, in contrast, the quantitative stand structure could be effectively regulated to maximize grower benefit without compromising the existing biodiversity. Optimization of the quantitative stand structure of homestead forests could be achieved by changing the species composition, specifically by increasing the percentage of commercially valuable species like Michelia champaca, Tectona grandis, Artocarpus chapalasha, Gmelina arborea, Litchi chinensis, Citrus grandis, Psidium guajava, Lagerstroemia speciosa, Swietenia mahogany, etc., reducing the percentage of species like Mangifera indica, Artocarpus heterophyllus, Cocos nucifera, Samanea saman, Spondias pinnata, Phoenix sylvestris, etc., and eradicating species like Lannea coromandelica and Ficus benghalensis. It was estimated that the optimal relative density of fruit and timber species that would generate optimal financial benefit would be 40.4% and 59.6%, respectively. 相似文献
8.
Determining the optimal rotation period was a crucial component of forest sustainable management strategies, especially under climate change. This paper had two objectives: (1) to determine the economic benefits and optimal rotation periods for timber production when coupled to carbon sequestration, as predicted by time series prediction models for Pinus tabulaeformis plantations in China; and (2) to evaluate how different carbon prices and interest rates affected optimal rotation periods using the forest land expectation value. The results suggested that time series prediction models were valuable for estimating timber volumes and carbon sequestrations based on surveys of different-aged stands. Importantly, since integrating carbon sequestrations into timber production benefits did not increase optimal rotation periods, this should promote P. tabulaeformis plantation management. In the sensitivity analysis, a higher carbon price increased the profitability of carbon sequestration and timber production, but not optimal rotation periods, though they were reduced under higher interest rates. In conclusion, incorporating both timber production and carbon sequestration benefits would sharply increase forest-based revenues, while realizing the carbon sequestration potential of P. tabulaeformis plantations. This approach was clearly useful to the development of reforestation/afforestation projects trying to mitigate climate change and also provided a theoretical basis for sustainable forest management. 相似文献
9.
Phan Sy Hieu 《Small-Scale Forestry》2004,3(1):85-98
This paper reviews the changing forestry policies in Vietnam from the 1980s to the present. The role of forestry in the economy,
developments in forest industries, government programs to encourage plantation establishment, and trade progress are examined.
It is concluded that while there is a shortage of timber, log prices to growers are low due to high markups along the supply
chain. Government programs such as the Five Million Hectares forestry program will lead to major supply increases in the future,
but improvements in timber marketing will remain critical. While forestry exports from Vietnam have increased in the last
decade, this has been based mainly on traditional handicrafts. Small enterprise size and lack of advanced technology limit
export competitiveness. 相似文献
10.
《Journal of Sustainable Forestry》2013,32(4):53-78
Abstract Japan has been the world's major timber importer for close to four decades. In order to meet its demand for timber, Japan has extended its ecological shadows in many parts of Southeast Asia, and has had a significant indirect impact on Southeast Asia's commercial forests. This paper will cast light on the effects of past and current timber resource exploitation in the East Malaysian states of Sabah and Sarawak by focusing on concepts of cronyism and Japan's ecological shadows. The article closes with some suggestions for possible ways to harvest in a more sustainable manner, and internalize externalities of the timber market. 相似文献
11.
12.
Design and development of agroforestry systems for Illinois,USA: silvicultural and economic considerations 总被引：1，自引：0，他引：1
Recommended managerial inputs and associated outputs expected from practicing agroforestry on marginal farm lands in the central
USA are discussed. Modeled management combinations are based on five timber species, three sites indices, three timber growth
rates, five agricultural crops, all common crop rotations, and three tillage systems. Black walnut (Juglans nigra L.), combined with row crop production, is used to illustrate a specific multicropping alternative. Based on net present value,
modeled agroforestry systems incorporating black walnut performed better on the better sites and at the medium to high timber
growth rates whereas management systems using red oak (Quercus rubra L.) with row crops performed better on the poorer sites and at the lower growth rates. For agroforestry to be competitive with
traditional agriculture, medium to high timber growth rates were necessary. Also, lower interest rates and the existing U.S.
income tax structure favored agroforestry versus traditional agriculture. Substantial increases in net income may be possible
through incorporating other income producing activities such as nut production within the agroforestry system. 相似文献
13.
樟树资源及其开发利用 总被引：4，自引：2，他引：2
樟树为樟科樟属常绿乔木,为国家Ⅱ级保护树种,主要分布在中国（包括台湾）南部各省,越南、日本等地亦有分布。在中国南方,樟树是著名的多用途乡土珍贵用材和经济树种,一直被人们所重视。文章从樟树的自然分布、生态习性、木材性质、用途、生长潜能、生产力与碳汇能力、遗传改良进展、当前开发利用中存在的问题与未来展望等方面,进行了综合的论述。 相似文献
14.
Compiling Market and Other Financial Data on Smallholder Forestry in Leyte, the Philippines 总被引：1，自引：1，他引：0
Edwin Cedamon Steve Harrison John Herbohn Eduardo Mangaoang 《Small-Scale Forestry》2011,10(2):149-162
Data collection and maintenance of databases concerning smallholder forestry presents special problems in developing countries.
This paper examines forestry data collection experiences in a series of research projects in Leyte, Philippines, supported
by the Australian Centre for International Agricultural Research, and the prospects for developing forestry accounting networks.
A variety of financial data have been collected in relation to seedling production, plantation performance and timber marketing.
Seedling production cost and revenue data have been obtained through snapshot surveys conducted in 2002 and 2008, and repeated
attempts have been made to estimate financial returns from growing the most popular tree species. Diverse sources have been
identified for timber market information. On the supply side, these include government records of registered plantations,
obtaining inventory data from barangay (community) leaders, and reporting information about timber available for harvest on
community notice boards. On the demand side, official records of registered timber merchants have been accessed, a detailed
survey of timber processors has been conducted, and estimates are being made of apparent per capita timber consumption by
district. Experiences in the Philippines reinforce that the potential for forestry accounting networks is limited by the resource-constrained
situations of developing countries, placing greater reliance on one-off surveys. Use of pre-existing local networks and institutional
structures offers potential for routine collection of forestry data, such as through barangay (village) leaders in the Philippines. 相似文献
15.
This study explores the regeneration of 12 selected timber species within an area of selective logging in a neotropical rainforest in Guatemala. A part of the Maya Biosphere Reserve, in which timber harvest is performed by the cooperative Unión Maya Itzá, makes up the study area. We report the results of an inventory of 12 species over an area of 300 ha and detailed recording of saplings and seedlings for 10 selected timber species in five 1-ha plots. In the latter, characteristics of gaps (gap size and location, and vegetation cover) were also recorded. The recorded density of timber seedlings and saplings in the study area was low. The low present density of future harvestable timber species suggests that the total volume of harvested trees will decline from harvest to harvest in the future if an interval between subsequent logging events of 25 yr is used and if the logging intensity prescribed by the current management plan is upheld. Measures needed for forestry in this region to be sustainable are discussed. 相似文献
16.
The structure of Japanese timber markets has changed drastically during recent decades. After the introduction of a large
amount of imported softwood products. Japanese timber producers have faced global competition with foreign timber suppliers
such as Canada, the US, and recently Nordic countries. In this paper, we present a forest sector model for lumber markets
with a focus on eight aggregate regions (Tohoku, Kanto, Hokuriku, Chubu, Kinki, Chugoku, Shikoku, and Kyushu) in Japan. The
proposed model is based on the Samuelson-partial equilibrium formulation, which searches for an optimal solution by maximizing
the net social payoff subject to demand and supply constraints. A nonlinear programming solution technique is incorporated
into the proposed model. Three types of lumber are considered,i.e., domestic lumber, the lumber processed in Japan from imported logs, and imported lumber from the US and Canada. Using data
for 1998, our analysis indicates that the derived equilibrium solution has a higher price for the imported lumber supply in
all regions, and a lower price for the other two products in most regions than the actual current price in 1998. The derived
net social payoff gains 1.6% compared with the one derived with the current set of prices and quantities.
This is research was supported by the Grant-in-Aid for scientific Research (No.11691090) from the Ministry of Education, Culture,
Science, Sports, and Technology of Japan. 相似文献
17.
Valery Kozlov 《Wood material science & engineering》2014,9(3):156-161
AbstractService life of timber structures in the north of Europe is decreased mainly by biological agents. Increasing risk of biological infestation due to global warming is widely discussed nowadays. Historic timber structures which have been monitored for decades provide us with valuable information on this subject. An investigation of the structures in the Kizhi museum, located in the northwest of Russia was carried out in the 1970s and in 2011–2012. Identification of wood-decay fungi that destroy constructive elements of seventeenth- and nineteenth-century monuments showed that the most frequent damages are caused by brown rot fungi. At the same time, imperfect fungi and ascomycetes which cause soft rot began to play a significant role in damaging historic timber structures. Borers (Hadrobregmus pertinax L. and H. confusus Kraaz) play the leading part in reducing the service life of seventeenth- and nineteenth-century heritage objects. During a forest inventory, some wood-borers not registered previously as timber structure pests in the Kizhi archipelago region (Republic of Karelia, Russia) were found. Twenty-seven species of foliose and fruticose lichens and ten species of crustose lichens were found on the monuments' structural elements. 相似文献
18.
Peter Stapel Julia K. Denzler Jan-Willem G. van de Kuilen 《Wood material science & engineering》2017,12(1):1-13
The origin of the raw material is a key aspect for strength grading of timber. Large grading areas are favored by the sawmilling industry as they require less effort in handling and documentation during the production process. However, large growth areas can also cause problems, as too high mechanical properties can be declared or yields may become uneconomical. The presented study presents a method that should allow for timber from different countries to be combined into a single grading area. Additionally, the influence on the yield for guaranteeing timber properties for differently defined populations is analysed. In this process, a number of available calculation methods for characteristic values for modulus of rupture, modulus of elasticity, and density are considered as the determination method also influences the final yield. Non-destructive and destructive test data from 8487 spruce specimens from Europe tested in bending or tension are the basis for the presented study. Based on the grading results the presented method is able to simply identify countries that may be combined. The definition of pan-European grading areas seems problematic if characteristic timber properties need to be guaranteed separately for each individual country as it may result in a severe drop in yield. However, checking timber properties only for the European population is unsatisfying as calculated timber properties considerably vary depending on the origin. As for the calculation method, the preferred method itself seems to have less impact on bending class assignments then on tension class assignments. 相似文献
19.
《Scandinavian Journal of Forest Research》2012,27(5):492-502
Abstract Lack of accurate tools for detecting insect infestation in timber remains a big challenge for pest management authorities. Seven non-destructive insect detection technologies were used to assess their effectiveness in detecting insect borers and termites in timber samples. These technologies were: Termatrac®; Tramex Moisture tester; Acoustic Emission Device (AED-200L®); X-ray, thermal imaging camera; a termite detector dog; and trained quarantine inspectors using standard visual inspection (VI). The timber samples of Acacia parramattensis and Acacia decurrens used for the trial were naturally infested timber branches; timber blocks inoculated with lyctine beetles; timber blocks naturally infested with termites; and un-infested controls. All timber samples used were destructively sampled at the end of the trial to confirm the presence or absence of insects. The detector dog was 100% effective in detecting natural infested termite colonies but was totally ineffective in detecting termites on artificially inoculated timber blocks. The moisture metre and the thermal image camera were 100% effective in detecting large termite colonies but ineffective in detecting other insects in dry timber samples. The effectiveness of other methods of detecting insects or termites varied considerably. The AED was 79% effective, Termatrac 70%, X-ray 40% and VI 35%. Implications of these findings for quarantine and inspection purposes are discussed. 相似文献
20.
《Scandinavian Journal of Forest Research》2012,27(6):559-567
Abstract Methodology to assess the potential for energy wood procurement in Russia is described in this article and applied to the Leningrad region. Wood from thinnings, logging residues, non-industrial roundwood and residues from sawmilling are considered as sources for energy production. Energy wood available in the region, based on the 2004 actual cut, is approximately 4 million m3. Nearly 86% of this is non-industrial roundwood and felling residues, and 14% is by-products from sawmilling. Almost two-thirds of the non-industrial roundwood and felling residues are in cutting areas and one-third is in central processing yards. Deciduous tree species (birch and aspen) dominate in energy wood, representing about 65% of the total amount of felling residues and non-industrial wood. It is possible to intensify utilization of forest resources and thereby also to increase the use of wood in energy production. The total amount could be 54% higher if the allowable cut was fully utilized and 124% higher if thinnings were also utilized completely. There are, however, significant intraregional differences, as the current rate of utilization of forest resources varies in the region. 相似文献