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1.
A study has been conducted to establish the influence of knot area ratio based grading rules on the bending properties of full size Hem-fir (Western Hemlock and Amabilis fir) timber used in Japanese post and beam building construction. Bending strength and modulus of elasticity test results and out turn information on the 105×105 mm2, 90×90 mm2, 45×105 mm2, 30×105 mm2, and 45×90 mm2 specimens are presented in this paper. The in-grade test results indicate that the knot area ratio based grading rules can be successfully applied to the Hem-fir timber.
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F. LamEmail: Phone: +1-604-8226256Fax: +1-604-8229104 |
2.
Environmental concern accelerated development of new wood preservatives having low mammalian toxicity in addition to high protective effectiveness. PHN 130 and PHN 130 G have been developed recently by KOHMIX Ltd. in Japan as environmentally safe, fire-proof boron containing compounds. Beyond their proved fire-proof properties, stability of loaded chemical in wood at humid service conditions and decay resistance are required to be known for effective and broad use of these compounds in wood preservation. Results indicated that PHN imparted complete decay resistance to wood against brown- and white-rot fungi Tyromyces palustris and Coriolus versicolor, respectively. Protection efficacy of PHN also continued despite severe weathering conditions provided that impregnation is done by an undiluted solution. PHN 130 G appeared more effective than PHN 130 in this respect. However, both compounds were leachable from treated wood regardless of retention level or physical restriction of water access into wood by compression.This revised version was published online in April 2005 with a corrected date of receipt of the article.
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Ergün BaysalEmail: Phone: +90-252-2238612Fax: +90-252-2238511 |
3.
J. J. Corral Rivas J. G. Álvarez. González Oscar Aguirre F. J. Hernández 《European Journal of Forest Research》2005,124(2):133-142
In this paper, we evaluated how well-selected distance-dependent and distance-independent competition indices explain individual tree basal area growth of trees, growing in mature and even-aged stands of Pinus cooperi Blanco. A total of 18 competition measures were analyzed of which six do not need tree location (distance-independent) and 12 that utilize tree location (distance-dependent). The competition situation of a stand and/or an individual tree was studied using 11 different competitor selection methods. The mean square error reduction relative to no-competition was used to judge the performance of each competition index. It was found that the best distance-independent competition indices performed as well as the best distance-dependent competition indices. It was concluded that the BALMOD-index would be a good competition index to be incorporated into further individual tree basal area growth models for the study area.
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J. J. Corral RivasEmail: Phone: +49-551-393554Fax: +49-551-399787 |
4.
A model of public cost-sharing in private forest investment is proposed to describe the substitution between the private financing of investments and public investment assistance. The substitution depends on the curvature conditions of the forest investment function on forest stock. When the second-order investment effects are close to zero or when they do not exist, the funding substitution will not take place. A simultaneous econometric model for private and public funding employing forest incomes, forest income taxes, interest rates, investment scale and market wood price expectations as exogenous variables is estimated. The model estimation based on Finnish regional data in 1983–2000 rejects the substitution alternative. A 10% increase in private investment funding increases the demand for public funding at the same rate, but a 10% increase in public funds will increase the private funds supply by 2.5%. Significant income effects are found only in the case of private funding. In northern Finland, the scale effects are large for public financial assistance. The effects of the income tax reform on the private supply of funds are positive, especially for the new wood-sales profit taxation, whereas the interest rate and price expectation effects are negative.
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Mikael LindenEmail: Phone: +358-13-2514225Fax: +358-13-2513290 |
5.
Development of wood procurement in Northwest Russia: round wood balance and unreported flows 总被引:2,自引:0,他引:2
This paper analyses industrial round wood flows into, within, and out of Northwest regions of Russia. We examine sawlogs, pulpwood, and fuelwood used for industrial purposes obtained from logging, and chips obtained from the wood-processing industry. We attempt to clarify different recent trends in wood harvesting, industrial round wood export, and forest industries development that have an influence on unreported wood in Russia. Our method, which uses wood balance diagrams, provides an interpretation of data from different Russian sources in order to offer better transparency regarding wood flows from forests to mills. It also helps to explain the apparent imbalance between round wood supply and demand and it helps one to assess the possible share of unreported industrial round wood production in Northwest Russia. Based on annual forest-related statistical data available from the Ministry of Natural Resources, the State Committee of Statistics, and the Russian Federation’s Customs Department, unreported round wood flows can be estimated to be 23% of the total industrial round wood production, or approximately 9 million m3 u.b. per year. Unreported round wood flows are more common in export oriented regions that have poorly developed forest industries.
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Yuri GerasimovEmail: Phone: +358-102-113253Fax: +358-102-113251 |
6.
This article studies the possibility of using auctions as a policy instrument in conservation programs. In particular, it
provides insight into the main concerns that need to be dealt with when implementing conservation auctions. To show the cost
saving potential of this policy instrument, we also calculate the social welfare improvement that can be obtained for an afforestation
project in Flanders. When developing conservation policies, it is thus worthwhile to consider auctions as an alternative policy
instrument.
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Sandra RousseauEmail: |
7.
How to foster good husbandry of private native forests 总被引:2,自引:2,他引:0
Jerome K. Vanclay 《Small-Scale Forestry》2007,6(2):205-218
It is generally agreed that effective conservation requires the cooperation of private landholders to complement reserve-based
efforts, but there is little agreement about how this can best be achieved. Various stakeholders lobby for tough regulations,
for greater landholder freedom, and for incentives for activities or outcomes. A review of these alternatives suggests an
emerging consensus that incentives are the most effective approach. Policy-makers should consider incentive-based approaches
such as stewardship support to foster conservation outcomes on private lands.
相似文献
Jerome K. VanclayEmail: |
8.
Non-industrial private-forest owners: possibilities for increasing adoption of close-to-nature forest management 总被引:1,自引:1,他引:1
The concept of close-to-nature management combines an economic use of forests with nature conservation. Today, this compromise between central interests in forest management is seen as an appropriate model for the majority of the forestland in Germany. In attempting to implement the concept nationwide, the category of privately owned forests, which make up 46% of Germanys forested area, has received increasing political attention. The adoption of close-to-nature forestry practices within private forests is difficult to describe due to exceedingly diverse owner-specific factors. Applying a socio-psychological behavioural model that combines the theory of planned behaviour, the cultural theory and the modernisation theory, this article presents an analysis of how non-industrial private-forest (NIPF) owners in the Black Forest region of Germany assess and implement close-to-nature forestry practices. The study is based on a written survey of approximately 900 randomly selected owners of forestlands ranging in size from 0.1–200 ha. The main factors identified that affect the adoption of close-to-nature forestry practices include perceptions of forest conditions and of opportunities to influence these conditions as well as the influences of social surroundings on the forest owners. Owners were classified into three types based on multiple characteristic features: economically interested, conceptually interested, and uninterested forest owners. Based on these results, opportunities to encourage NIPF owners to use close-to-nature forestry practices were explored.
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Claudia BielingEmail: Phone: +49-761-2033713Fax: +49-761-2033705 |
9.
Consuming Fuel and Fuelling Consumption: Modelling Human Caloric Demands and Fuelwood Use 总被引:1,自引:0,他引:1
This paper describes a conceptual framework that was developed to integrate livestock, human, cultivation and forest constraints
to model community fuelwood consumption over a 25-year planning horizon. This framework was constructed as an energy balance
based on human caloric requirements in order to examine the effects of household-level decisions for nutrition, fuelwood and
land use. A scenario from a virtual community in Uganda is presented to illustrate the utility of this model to allow rapid
policy and scenario evaluation. User-defined inputs combined with published research data are used in simulating resource
responses and energy consumption rates. This model is a potential tool to monitor fuelwood consumption and to understand the
implications of various land-use practices.
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Joel HartterEmail: |
10.
SWOT analyses and SWOT strategy formulation for forest owner cooperations in Austria 总被引:4,自引:0,他引:4
Peter Rauch 《European Journal of Forest Research》2007,126(3):413-420
Forest owner cooperations (FOC) are bundling wood supply from small-scale forests and some also offer additional services,
such as wood harvesting or planting. FOCs are growing throughout Europe in terms of the managed timber volume. The increasing
timber demand of forest-based industries as well as the new, rapidly growing demand for energy plants could lead to an under-supply
in the following years in Europe. Because of high harvesting arrears in small-scale forests, FOCs are seen as an opportunity
to overcome this foreseen timber shortage. The paper maps out timber mobilisation strategies using the SWOT (Strengths, Weaknesses,
Opportunities and Threats) approach.
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Peter RauchEmail: |
11.
This research utilises a contingent behaviour valuation technique to value a number of improvements to recreational facilities
in small-scale forests in Ireland. Willingness-to-pay estimates have previously been made for Coillte (Ireland’s state-owned
forestry company) trails and forests. The total non-market value of Irish forests has also been examined. This paper adds
to the literature by being the first to estimate the consumer surplus associated with recreational enhancements to Irish small-scale
forest resources. The results presented indicate that community owned small-scale forestry can contribute enormously to the
wellbeing of nearby urban residents, through the provision of outdoor recreational services.
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Stephen HynesEmail: |
12.
The practical application of the orientation distribution function (ODF), being the three-dimensional representation of the
texture function, was presented. The investigations of the crystallograpically organized regions of wood were performed. The
experimental methods of the X-ray diffraction were discussed in detail. The incomplete pole figures were measured in order
to calculate the ODF. The dominant components of the crystallographical texture of wood were determined from the obtained
ODF. The obtained texture function was also used to derive the complete pole figures, additional non-measurable figures as
well as inverse pole figures. The figures were used to perform additional analysis of the crystallographical organization.
The traditional concept of the microfibril angle was enhanced by defining two transformation parameters, i.e. a crystallographical
axis and an angle of rotation.
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Wiesław OlekEmail: |
13.
Markku J. Penttinen 《European Journal of Forest Research》2006,125(4):335-343
This paper analyses timber harvesting in the Finnish economic and wood production environment. Empirical evidence including stumpage prices, silvicultural costs, etc., since 1949 covers all non-industrial private forestry. Stumpage price and volume growth processes are proxied by GBMs. Optimal harvesting age solutions and numerical results recognising price drift, price and growth volatility, volume growth, value growth and stand establishment costs, as well as thinning benefits, are provided for Scots pine. Moreover, comparative static and sensitivity solutions, including numerical results, show the impact of the discount rate, price drift, and price and growth volatilities on optimal harvesting age. Price volatility prolonged harvesting age by some 5–9 years, and growth volatility by about 1–2, but negative price drift for discount rates from 5 to 2% fell by roughly 6–10 years. Ignoring the future thinning benefits prolonged the harvesting age only by 1–2 years, but ignoring future stand establishment costs reduced it by 2–4 years. Including the price drift and volatility violated the 70 year age limit in the Forest Act for discount rates exceeding 3.5%. The recommended harvesting age of 80 years could be established only by ignoring the price drift. In all, this study produces solutions and programs that can be incorporated into a forest management planning software product widely used in Finland (Hynynen et al. in For Ecol Manage 207(1–2):5–18, 2005).
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Markku J. PenttinenEmail: Phone: +358-10-2112244Fax: +358-10-2112104 |
14.
The Increasing Importance of Small-Scale Forestry: Evidence from Family Forest Ownership Patterns in the United States 总被引:2,自引:2,他引:0
The state-level distribution of the size of family forest holdings in the contiguous United States was examined using data
collected by the USDA Forest Service in 1993 and 2003. Regressions models were used to analyze the factors influencing the
mean size and structural variation among states and between the two periods. Population density, percent of the population
at least 65 years of age, percent of the population residing in urban areas, per capita income, income inequality, and per
capita private forestland were found to be significantly correlated with the structure of landholding size. This paper suggests
that the number and proportion of small-scale family forest owners in the United States are both increasing due to the increasing
importance of non-timber amenities to forest landowners.
相似文献
Y. ZhangEmail: |
15.
Social and ecological issues for private native forestry in north-eastern New South Wales,Australia 总被引:1,自引:1,他引:0
Forests in north-eastern New South Wales have often been the focus of controversy. The tension between production and preservation
continues and hampers current negotiations for a code of practice for private native forestry. The structure of many private
forests reflects past mismanagement, and silvicultural intervention would benefit both conservation and production objectives,
but such intervention is rarely financially viable. This paper sets out the economic and ecological basis for private native
forestry. Both the timber industry and nature-based tourism are major contributors to the local economy, and both rely in
part on private native forests. Draft regulations currently under negotiation do not offer incentives for improved private
forest management.
相似文献
V. Alex JayEmail: |
16.
The endozoochorous dispersal of vascular plant species by red deer (Cervus elaphus) was investigated in three forest areas of Schleswig-Holstein and Lower Saxony. The primary aim of this study was to determine of which plant species and in what numbers diaspores are dispersed by red deer, an animal with eminently large home ranges during a single day as well as over the year. A second aim was to examine the significance of endozoochory for plant species composition and diversity in forests. Special emphasis was placed on whether there are differences between the three study sites and in the course of the vegetation period. Freshly deposited faecal pellet groups were collected in the forests on five dates between May and November 2002 and viable seed content was determined by greenhouse germination (seedling emergence method). A total of 28,009 individuals representing 59 vascular plant species were detected in 220 dung samples. Red deer appears thus as an important vector for endozoochorous dispersal of plants. The number of seedlings found in the faecal pellets differs between plant species and research areas as well as in the course of the vegetation period. Dung seed content is largely dominated by one species, Urtica dioica. Grouping the species found in dung according to their habitat preference showed that mainly species that occur in forests as well as in open vegetation and non-forest species were dispersed endozoochorously, while species occurring mainly under a closed canopy were present in the excrements only in low numbers.
相似文献
Goddert von OheimbEmail: Phone: +49-4131-782845Fax: +49-4131-782808 |
17.
Julie Urquhart 《Small-Scale Forestry》2007,6(3):257-271
This paper examines the trade-offs between woodland management for timber and public good outputs in English woodlands. Recent
evidence suggests that some public good values may be declining as a result of a lack of woodland management. Such under-management
has been attributed to the decline in timber values and reduction in the productivity of woodlands and forests for timber
products. It is argued that assessing the management needs of woodlands in order to enhance public good outputs presents a
complex challenge and often depends on a variety of factors, including location, type of woodland, age, condition, substitutability
and ownership motivation. However, in most instances a moderate level of management (whether for timber or otherwise) is likely
to be beneficial for public good outputs.
相似文献
Julie UrquhartEmail: |
18.
P. Muukkonen 《European Journal of Forest Research》2007,126(2):157-166
Since biomass is one of the key variables in ecosystem studies, widespread effort has aimed to facilitating its estimation.
Numerous stand-specific volume and biomass equations are available, but these cannot be used for scaling up biomass to the
regional level where several age-classes and structural types of stands coexist. Therefore simplified generalized volume and
biomass equations are needed. In the present study, generalized biomass and volume regression equations were developed for
the main tree species in Europe. These equations were based on data compiled from several published studies and are syntheses
of the published equations. The results show that these generalized equations explain 64–99% of the variation in values predicted
by the original published equations, with higher values for stem than for crown components.
相似文献
P. MuukkonenEmail: |
19.
Research into the effects of seven management techniques on survival and growth of eucalypt seedlings planted on farmland
is reviewed. The techniques include: pre- and post-planting weed control; soil cultivation; fertiliser; mulch; tree guards/shelters;
and irrigation. The initial and ongoing effects of each technique are discussed—including the effects of timing, type and
quantity. Consideration is given to site, species and climatic influences. A statistical analysis of the published survival
rates is then presented, to provide information on the relative importance of, and interactions between, practices. The analysis
shows that maximum survival may be achieved by using one or two management techniques. Combining this result with the insights
gained from the review suggests that the use of soil cultivation and post-planting weed control are likely to achieve the
greatest improvements in early eucalypt survival and growth.
相似文献
Sonia GrahamEmail: |
20.
The assessment of a forest resource in national inventories provides a firm basis for the calculation of biomass and carbon
(C) stocks of forests. Biomass expansion factors (BEFs) and conversion factors provide a robust and simple method of converting
from forest tree stem volume to total forest biomass. These factors should be constructed on the basis of nationally specific
data in order to take account of regional differences in growth rates, management practices, etc. The objective of this study is to improve the accuracy of biomass estimation by calculating a range of age-dependant BEFs
from representative data that more accurately describe the allometry of present forests. The results from this study show
that the allocation of biomass to compartments in forest stands and throughout a rotation varies considerably, and that the
use of BEFs for the calculation of C stocks in forests of sub-timber dimensions is highly impractical.
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Brian TobinEmail: |