WorldWideScience

Sample records for prices timber harvest

  1. Timber harvesting with variable prices, costs and interest rates

    International Nuclear Information System (INIS)

    Penttinen, M.

    2000-01-01

    This papers solves the optimal harvesting time problem of a non- industrial private forest (NIPF) owner who typically has a forest management plan and merchantable forest stands. The optimal harvesting time is defined in a volatile market situation. The infinite period problem is also formulated to allow for variable stumpage prices and reforestation costs in a two-period framework, the first of which covers the near future with dynamic price and cost functions and the second the rest of the infinite future with trend price and cost functions. The existence and uniqueness of an optimal policy is demonstrated on the basis of the explicit quasi- concavity of the objective functions. First, the solutions are constructed with prices and costs dependent on stand age only. Both cases in which the same prices and costs hold for all periods and cases in which there are dynamic prices and costs in the first period and trend ones in subsequent periods are considered. Second, the age-dependent functions are multiplied separately by the calendar time dependent exponential terms. Solutions are provided both in the case with the same age-dependent functions and the case with dynamic functions for the first period and trend functions for the subsequent periods. The sensitivity and comparative static analyses are studied with respect to the interest rate, price and cost changes, both analytically and numerically. Optimal rotation solutions are presented with alternative competing volume growth functions. Final results are provided by a gross income growth function. Competing optimisation models are discussed, and alternative volume growth models and a value growth model are compared. The key notion of the research is the sensitivity and comparative static analysis of the optimal rotation solutions with respect to roundwood prices, reforestation costs and interest rates. Different local market parameter and alternative growth data estimates are applied in testing the impact of

  2. 1970 Oregon timber harvest.

    Science.gov (United States)

    Brian R. Wall

    1971-01-01

    The 1970 Oregon timber harvest of 7.98 billion board feet was the lowest recorded since the recession year of 1961 when 7.41 billion board feet of timber was produced. The 1970 log production figure was 12.8 percent below the 1969 harvest, the second consecutive year of declining production in Oregon.

  3. Computer Vision for Timber Harvesting

    DEFF Research Database (Denmark)

    Dahl, Anders Lindbjerg

    The goal of this thesis is to investigate computer vision methods for timber harvesting operations. The background for developing computer vision for timber harvesting is to document origin of timber and to collect qualitative and quantitative parameters concerning the timber for efficient harvest...... segments. The purpose of image segmentation is to make the basis for more advanced computer vision methods like object recognition and classification. Our second method concerns image classification and we present a method where we classify small timber samples to tree species based on Active Appearance...... to the development of the logTracker system the described methods have a general applicability making them useful for many other computer vision problems....

  4. Building aggregate timber supply models from individual harvest choice

    Science.gov (United States)

    Maksym Polyakov; David N. Wear; Robert Huggett

    2009-01-01

    Timber supply has traditionally been modelled using aggregate data. In this paper, we build aggregate supply models for four roundwood products for the US state of North Carolina from a stand-level harvest choice model applied to detailed forest inventory. The simulated elasticities of pulpwood supply are much lower than reported by previous studies. Cross price...

  5. Timber price dynamics following a natural catastrophe

    Science.gov (United States)

    Jeffrey P. Prestemon; Thomas P. Holmes

    2000-01-01

    Catastrophic shocks to existing stocks of a renewable resource can cause long-run price shifts. With timber, these long-run price shifts may be accompanied by a short-run price drop due to salvage. Hurricane Hugo damaged 20 percent of southern pine timber in the South Carolina Coastal Plain in 1989. To estimate the...

  6. Timber Price Dynamics Following a Natural Catastrophe

    OpenAIRE

    Jeffrey P. Prestemon; Thomas P. Holmes

    2000-01-01

    Catastrophic shocks to existing stocks of a renewable resource can cause long-run price shifts. With timber, these long-run price shifts may be accompanied by a short-run price drop due to salvage. Hurricane Hugo damaged 20% of southern pine timber in the South Carolina Coastal Plain in 1989. To estimate the short- and long-run effects of the hurricane on the prices of timber stocks, we estimated an intervention model of the residuals of cointegration of South Carolina sawtimber and pulpwood ...

  7. Supply Chain Planning for a Timber Harvesting Plus Sale Tender

    Directory of Open Access Journals (Sweden)

    Josef Holoubek

    2015-01-01

    Full Text Available Since 2010, the Czech State Forest Enterprise has been inviting timber-harvesting tenders while insisting on the forestry company purchasing the timber from the felled trees as well. To win, a tender must offer the greatest difference between the price of the timber purchased and the cost of the operations. Thus, the forest companies are now facing new problem: apart from minimizing the logging costs they are searching for a cross-cutting and mill-distribution strategy that maximizes the selling price of the harvested timber. The optimization model devised by the present paper provides support for finding an optimal timber selling strategy and, as an important contribution, include a detailed plan for cross-cutting the logs and assign them to the particular customers. We keep the support accessible via common office software and the cross-cutting and customer-assigning problem is formulated as a linear programming model for EXCEL, a particular real-world problem is solved and, using expert comparison, the model appears to provide very good results.

  8. Space-time modeling of timber prices

    Science.gov (United States)

    Mo Zhou; Joseph Buongriorno

    2006-01-01

    A space-time econometric model was developed for pine sawtimber timber prices of 21 geographically contiguous regions in the southern United States. The correlations between prices in neighboring regions helped predict future prices. The impulse response analysis showed that although southern pine sawtimber markets were not globally integrated, local supply and demand...

  9. Timber products output and timber harvests in Alaska: projections for 1992-2010.

    Science.gov (United States)

    D.J. Brooks; R.W. Haynes

    1994-01-01

    Projections of Alaska timber products output, the derived demand for raw material, and timber harvest by owner are developed from a trend-based analysis. By using a spread-sheet model, material flows in the Alaska forest sectorare fully accounted for. Demand for Alaska national forest timber is projected and depends on product output and harvest by other owners. Key...

  10. California’s forest products industry and timber harvest, 2006

    Science.gov (United States)

    Todd A. Morgan; Jason P. Brandt; Kathleen E. Songster; Charles E. Keegan; Glenn A. Christensen

    2012-01-01

    This report traces the flow of California’s 2006 timber harvest through the primary wood products industry (i.e., firms that process timber into manufactured products such as lumber, as well as facilities such as pulp mills and particleboard plants, which use the wood fiber or mill residue directly from timber processors) and provides a description of the structure,...

  11. Enviromentally Sound Timber Extracting Techniques for Small Tree Harvesting

    Science.gov (United States)

    Lihai Wang

    1999-01-01

    Due to large area disturbed and great deal of energy cost during-its operations, introducing or applying the appropriate timber extracting techniques could significantly reduce the impact of timber extraction operations to forest environment while pursuing the reasonable operation costs. Four environmentally sound timber extraction techniques for small tree harvesting...

  12. Alaska's timber harvest and forest products industry, 2005

    Science.gov (United States)

    Jeff M. Halbrook; Todd A. Morgan; Jason P. Brandt; Charles E. Keegan; Thale Dillon; Tara M. Barrett

    2009-01-01

    This report traces the flow of timber harvested in Alaska during calendar year 2005, describes the composition and operations of the state's primary forest products industry, and quantifies volumes and uses of wood fiber. Historical wood products industry changes are discussed, as well as trends in timber harvest, production, and sales of primary wood products....

  13. Alaska’s timber harvest and forest products industry, 2011

    Science.gov (United States)

    Erik C. Berg; Charles B. Gale; Todd A. Morgan; Allen M. Brackley; Charles E. Keegan; Susan J. Alexander; Glenn A. Christensen; Chelsea P. McIver; Micah G. Scudder

    2014-01-01

    This report traces the flow of timber harvested in Alaska during calendar year 2011, describes the composition and operations of the state’s primary forest products industry, and quantifies volumes and uses of wood fiber. Historical wood products industry changes are discussed, as well as trends in timber harvest, production, export, sales of primary wood products,...

  14. Global modelling to predict timber production and prices: the GFPM approach

    Science.gov (United States)

    Joseph Buongiorno

    2014-01-01

    Timber production and prices are determined by the global demand for forest products, and the capability of producers from many countries to grow and harvest trees, transform them into products and export. The Global Forest Products Model (GFPM) simulates how this global demand and supply of multiple products among many countries determines prices and attendant...

  15. Profitability of timber harvesting and timber transportation enterprises

    International Nuclear Information System (INIS)

    Rajamaeki, J.

    1996-01-01

    In co-operation with the major companies contracting out forestry work and Statistics Finland, Metsaeteho carried out a project with the objective of analysing the economic profitability of timber harvesting and transportation enterprises in 1994. The calculation of profitability was based on utilisation of last livelihoods taxation data (EVR) that Statistics Finland was in possession of. The basic material comprised data that the companies contracting out forestry work had full-time entrepreneurs. There were 255 forestry machine contractor enterprises and 270 trucking enterprises. Statistics Finland was responsible for computations of the results of the project. The calculation of the indicators of profitability was based on the recommendations of Yritystutkimusneuvottelukunta, a committee looking into the functioning of enterprises. The year 1994 was a good year from the viewpoint of profitability of both forestry machine contractors as well as trucking enterprises. With full depreciations and salary adjustments attended to, both enterprise groups still showed a mean profitability of ca. 8 %. The yield of invested capital was ca. 25 %. The differences in profitability among enterprises were great in both groups and in different parts of the country

  16. Montana's forest products industry and timber harvest, 2004

    Science.gov (United States)

    Timothy P. Spoelma; Todd A. Morgan; Thale Dillon; Alfred L. Chase; Charles E. Keegan; Larry T. DeBlander

    2008-01-01

    This report traces the flow of Montana's 2004 timber harvest through the primary wood-using industries; provides a description of the structure, capacity, and condition of Montana's primary forest products industry; and quantifies volumes and uses of wood fiber. Historical wood products industry changes are discussed, as well as changes in harvest, production...

  17. The Effect of Urban Sprawls on Timber Harvesting

    Science.gov (United States)

    Stephen A. Barlow; Ian A Munn; David A. Cleaves; David L. Evans

    1998-01-01

    In Mississippi and Alabama, urban population growth is pushing development into rural areas. To study the impact of urbanization on timber harvesting, census and forest inventory data were combined in a geographic information system, and a logistic regression model was used to estimate the relationship between several variables and harvest probabilities....

  18. Modeling ground-based timber harvesting systems using computer simulation

    Science.gov (United States)

    Jingxin Wang; Chris B. LeDoux

    2001-01-01

    Modeling ground-based timber harvesting systems with an object-oriented methodology was investigated. Object-oriented modeling and design promote a better understanding of requirements, cleaner designs, and better maintainability of the harvesting simulation system. The model developed simulates chainsaw felling, drive-to-tree feller-buncher, swing-to-tree single-grip...

  19. Forest soil biology-timber harvesting relationships: a perspective

    Science.gov (United States)

    M. F. Jurgensen; M. J. Larsen; A. E. Harvey

    1979-01-01

    Timber harvesting has a pronounced effect on the soil microflora by wood removal and changing properties. This paper gives a perspective on soil biology-harvesting relationships with emphasis on the northern Rocky Mountain region. Of special significance to forest management operations are the effects of soil micro-organisms on: the availability of soil nutrients,...

  20. Idaho's forest products industry and timber harvest, 2011

    Science.gov (United States)

    Eric A. Simmons; Steven W. Hayes; Todd A. Morgan; Charles E. Keegan; Chris Witt

    2014-01-01

    This report traces the flow of Idaho’s 2011 timber harvest through the primary industries; provides a description of the structure, capacity, and condition of Idaho’s industry; and quantifies volumes and uses of wood fiber. Historical wood products industry trends are discussed, as well as changes in harvest, production, employment, and sales.

  1. Harvest choice and timber supply models for forest forecasting

    Science.gov (United States)

    Maksym Polyakov; David N Wear

    2010-01-01

    Timber supply has traditionally been modeled using aggregate data, whereas individual harvest choices have been shown to be sensitive to the vintage and condition of forest capital stocks. In this article, we build aggregate supply models for four roundwood products in a seven-state region of the US South directly from stand-level harvest choice models applied to...

  2. Effects of timber harvest following wildfire in western North America

    Science.gov (United States)

    David L. Peterson; James K. Agee; Gregory H. Aplet; Dennis P. Dykstra; Russell T. Graham; John F. Lehmkuhl; David S. Pilliod; Donald F. Potts; Robert F. Powers; John D. Stuart

    2009-01-01

    Timber harvest following wildfire leads to different outcomes depending on the biophysical setting of the forest, pattern of burn severity, operational aspects of tree removal, and other management activities. Fire effects range from relatively minor, in which fire burns through the understory and may kill a few trees, to severe, in which fire kills most trees and...

  3. The Four Corners timber harvest and forest products industry, 2012

    Science.gov (United States)

    Colin B. Sorenson; Steven W. Hayes; Todd A. Morgan; Eric A. Simmons; Micah G. Scudder; Chelsea P. McIver; Mike T. Thompson

    2016-01-01

    This report traces the flow of timber harvested in the "Four Corners" States (Arizona, Colorado, New Mexico, and Utah) during calendar year 2012, describes the composition and operations of the region’s primary forest products industry, and quantifies volumes and uses of wood fiber. Recent changes in the wood products industry are discussed, as well as trends...

  4. The Four Corners timber harvest and forest products industry, 2007

    Science.gov (United States)

    Steven W. Hayes; Todd A. Morgan; Erik C. Berg; Jean M. Daniels; Mike Thompson

    2012-01-01

    This report traces the flow of timber harvested in the "Four Corners" States (Arizona, Colorado, New Mexico, and Utah) during calendar year 2007, describes the composition and operations of the region's primary forest products industry, and quantifies volumes and uses of wood fiber. Historical wood products industry changes are discussed, as well as...

  5. 2005 wood harvests in France - a definite recovery for timber and dendro-energy

    International Nuclear Information System (INIS)

    Cinotti, B.

    2007-01-01

    After dropping to 32.8 million m 3 in 2003, sales of wood harvests continue the recovery that began in 2004 and have reached 37.2 million m 3 (+ 5%) i.e., slightly more than the level reached prior to the 1999 storms (36.9 million m 3 ). Workable timber sales have increased by 5.9% up to 22.1 million m 3 but are nonetheless 4.5% below their 1999 level (23.2 million m 3 ). Industrial round-wood harvests have remained stable at 12.2 million m 3 (of which 11.8 are pulpwood). Sales of firewood have increased 23% (2.9 million m 3 ). Pre-tax roadside value of the entire wood harvest is estimated to be 1.64 billion Euro. French production of sawing timber is 9.7 million cubic metres with sawn softwood timber stagnating (+ 0.5%) and a drop in sawn hardwood timber (- 4.6%). The effects of the storms at the end of 1999 on the business cycle are no longer perceptible. Their consequences on the structure of harvests and of businesses are beginning to be understood. Average wood prices increased considerably in 2005 and 2006. These rosier market conditions for unprocessed timber could be an opportunity to continue with restructuring of the sector, in particular so as to further streamline harvests and narrow the wide gap between loggable and actually logged volumes, as well as to review the distribution of added value between the various players in the forest-based industries. (authors)

  6. Computer software to estimate timber harvesting system production, cost, and revenue

    Science.gov (United States)

    Dr. John E. Baumgras; Dr. Chris B. LeDoux

    1992-01-01

    Large variations in timber harvesting cost and revenue can result from the differences between harvesting systems, the variable attributes of harvesting sites and timber stands, or changing product markets. Consequently, system and site specific estimates of production rates and costs are required to improve estimates of harvesting revenue. This paper describes...

  7. Timber harvesting patterns for major states in the central, northern, and mid-Atlantic hardwood regions

    Science.gov (United States)

    William G. Luppold; Matthew S. Bumgardner

    2018-01-01

    Timber harvesting is a major disturbance agent influencing the composition and structure of eastern hardwood forests. To better understand timber harvesting practices, we examined roundwood harvesting patterns in 13 eastern states in the Central, Mid-Atlantic, and Northern regions that contained high proportional volumes of hardwood in their forest inventories. Nearly...

  8. Noise, Worker Perception, and Worker Concentration in Timber Harvesting Activity

    Directory of Open Access Journals (Sweden)

    Efi Yuliati Yovi

    2012-01-01

    Full Text Available Timber harvesting activities are unquestionably related with high risk of work accidents and health disorders.Such activities were not only burdened the workers with heavy physical workloads due to uneasy workingenvironment, and massive work materials and tools, but also physiopsychologically burdened workers as theywere imposed with both mechanical and acoustic vibrations (noise produced by the chainsaw. However,  it is acommon practice that most of the workers still ignored the importance of the use of noise reduction devices suchas earmuff or ear plug.  This study was aimed to reveal the factual effects of noise on work concentration of theworkers to provide a scientific basis in supporting efforts in improving workers’ attitude.  The results confirmedthat chainsaw might produce noise during operation.  Noise intensities received by both right and left ears werenot significantly different, indicating that left-handed and normal workers received similar degree of noise inboth side of ears. Further, results also showed that there was a significant difference on the perception and workconcentration of chainsaw operators versus sedentary people to the noise.  These findings proved that hearingability of chainsaw operators had declined due to frequent noise exposure.Keywords: timber harvesting, physio-psychological disorder, noise, chainsaw

  9. Expanding the scale of forest management: allocating timber harvests in time and space

    Science.gov (United States)

    Eric J. Gustafson

    1996-01-01

    This study examined the effect of clustering timber harvest zones and of changing the land use categories of zones (dynamic zoning) over varying temporal and spatial scales. Focusing on the Hoosier National Forest (HNF) in Indiana, USA as a study area, I used a timber harvest allocation model to simulate four management alternatives. In the static zoning alternative,...

  10. Effects of timber harvest on aquatic vertebrates and habitat in the North Fork Caspar Creek

    Science.gov (United States)

    Rodney J. Nakamoto

    1998-01-01

    I examined the relationships between timber harvest, creek habitat, and vertebrate populations in the North and South forks of Caspar Creek. Habitat inventories suggested pool availability increased after the onset of timber harvest activities. Increased large woody debris in the channel was associated with an increase in the frequency of blowdown in the riparian...

  11. Clustering Timber Harvests and the Effects of Dynamic Forest Management Policy on Forest Fragmentation

    Science.gov (United States)

    Eric J. Gustafson

    1998-01-01

    To integrate multiple uses (mature forest and commodity production) better on forested lands, timber management strategies that cluster harvests have been proposed. One such approach clusters harvest activity in space and time, and rotates timber production zones across the landscape with a long temporal period (dynamic zoning). Dynamic zoning has...

  12. Successful and unsuccessful attempts to resolve caribou management and timber harvesting issues in west central Alberta

    Directory of Open Access Journals (Sweden)

    David Hervieux

    1996-01-01

    Full Text Available Research studies of woodland caribou in west central Alberta began in 1979 in response to proposed timber harvesting on their winter ranges. Using results from initial studies, timber harvest guidelines were developed. A recent review of these guidelines, and the assumptions on which they were based, has resulted in a renegotiation by government and industry of timber harvesting on caribou range in west central Alberta. Caribou range in west central Alberta overlaps many jurisdictional boundaries: federal and provincial lands, four Forest Management Agreement Areas, three Alberta Land and Forest Service Regions and two Alberta Fish and Wildlife Service Regions. This jurisdictional complexity in combination with other factors such as total allocation of the timber resources, high levels of petroleum, natural gas and coal extraction activities, a high level of concern by public groups for caribou conservation and recent understanding of woodland caribou needs for abundant space has made resolution of caribou/timber harvest conflicts exceedingly slow and often relatively unproductive. This paper reviews 10 years of trying to resolve conflicts between timber harvesting and caribou conservation through meetings, committees, integrated resource planning, policy papers and public consultation. We describe what might be learned by other jurisdictions that are trying to resolve similar caribou/timber harvesting issues. We conclude with an overview of recent timber harvest planning initiatives on caribou range in west central Alberta.

  13. Impact of professional foresters on timber harvests on West Virginia nonindustrial private forests

    Science.gov (United States)

    Stuart A. Moss; Eric. Heitzman

    2013-01-01

    Timber harvests conducted on 90 nonindustrial private forest properties in West Virginia were investigated to determine the effects that professional foresters have on harvest and residual stand attributes. Harvests were classified based on the type of forester involved: (1) consulting/state service foresters representing landowners, (2) industry foresters representing...

  14. 36 CFR 223.201 - Limitations on unprocessed timber harvested in Alaska.

    Science.gov (United States)

    2010-07-01

    ... Conservation and Shortage Relief Act of 1990 Program § 223.201 Limitations on unprocessed timber harvested in... or serious deterioration of logs unsalable locally because of an unforeseen loss of market, (c...

  15. Cattle and elk responses to intensive timber harvest.

    Science.gov (United States)

    Michael J. Wisdom; Bruce K. Johnson; Martin Vavra; Jennifer M. Boyd; Priscilla K. Coe; John G. Kie; Alan A. Ager; Norman J. Cimon

    2004-01-01

    Forested habitats for cattle and elk (Cervus elaphus) in the western United States have changed substantially in response to intensive timber management during the latter half of the 20th century. Consequently, the subject of how elk and other ungulates respond to timber management is a high-profile, long-standing issue that continues to be studied...

  16. Estimating and validating ground-based timber harvesting production through computer simulation

    Science.gov (United States)

    Jingxin Wang; Chris B. LeDoux

    2003-01-01

    Estimating ground-based timber harvesting systems production with an object oriented methodology was investigated. The estimation model developed generates stands of trees, simulates chain saw, drive-to-tree feller-buncher, swing-to-tree single-grip harvester felling, and grapple skidder and forwarder extraction activities, and analyzes costs and productivity. It also...

  17. Considering departures from current timber harvesting policies: case studies of four communities in the Pacific Northwest.

    Science.gov (United States)

    Con H Schallau; Paul E. Polzin

    1983-01-01

    U.S. Department of Agriculture regulations permit departures from current National Forest timber harvesting policies when "implementation of base harvest schedules.., would cause a substantial adverse impact upon a community .... " This paper describes the kinds of information needed for forest managers to adequately assess the relevance of the departure...

  18. Evaluating timber harvesting impacts on wildlife habitat suitability using FOREX

    Science.gov (United States)

    Chris B. LeDoux

    1997-01-01

    Precommercial, commercial, and final harvesting operations can impact wildlife habitat suitability by altering the vegetation composition on a given site. Harvesting operations remove trees and many times provide the necessary perturbation to trigger successional conditions different from those that existed prior to the harvest. Although these new successional changes...

  19. Simulating Harvest Schedule for Timber Management and Multipurpose Management in Teak Plantations

    Directory of Open Access Journals (Sweden)

    Tatang Tiryana

    2016-04-01

    Full Text Available Sustainable management of teak plantations in Java requires an improvement of the existing yield regulation method to optimize multiple benefits of the plantations at risk of stand destruction. This study was therefore aimed to formulate an alternative harvest scheduling model that integrates risk of stand destruction for supporting multipurpose management of teak plantations. The proposed model used a state-space planning model to simulate the dynamic of plantations due to timber harvesting and stand destruction, and then sought optimal solutions for 2 management scenarios, i.e. timber management that optimized total harvest volume and multipurpose management that optimized net present value (NPV while increasing carbon stocks. Using a case study on a typical teak plantation, this study confirmed that increasing destruction rates reduced harvest volumes, NPV, carbon stocks, and resulted in imbalanced ending age-class structures. Reducing cutting-age limit increased harvest volumes and NPV, but it also reduced carbon stocks of the plantations. Although the multipurpose management generated lower financial benefit, it maintained carbon stocks and produced better ending age-class structures compared to timber management. The proposed harvest scheduling model provides a useful planning tool for managing teak plantations.

  20. Erosion and soil displacement related to timber harvesting in northwestern California, U.S.A.

    Science.gov (United States)

    R.M. Rice; D.J. Furbish

    1984-01-01

    The relationship between measures of site disturbance and erosion resulting from timber harvest was studied by regression analyses. None of the 12 regression models developed and tested yielded a coefficient of determination (R2) greater than 0.60. The results indicated that the poor fits to the data were due, in part, to unexplained qualitative...

  1. Legal distinction between employee and independent contractor as applied to collective bargaining activities in timber harvesting

    Science.gov (United States)

    James E. Granskog; William C. Siegal

    1977-01-01

    Collective bargaining attempts by timber harvesting labor groups is often complicated by lack of a clear legal distinction between "employees" and "independent contractors." the primary criterion to make the distinction - the "right-to-control" test of common law - has now been amplified by a number of secondary tests, including: 1) the...

  2. Timber-harvest clearcutting and nutrients in the Northeastern United States

    Science.gov (United States)

    K. G. Reinhart

    1973-01-01

    The effect of ecosystem disturbance on nutrients in the system has been receiving widespread attention. An appraisal of research results in the Northeast indicates that timber-harvest clearcutting has not increased nutrient levels sufficiently to reduce water quality below drinking water standards. Losses of nutrients from clearcuttings in New Hampshire over a 2-year...

  3. Effects of group-selection timber harvest in bottomland hardwoods on fall migrant birds

    Science.gov (United States)

    John C. Kilgo; Karl V. Miller; Winston P. Smith

    1999-01-01

    Due to projected demands for hardwood timber, development of silvicultural practices that provide for adequate regeneration in southeastern bottomland hardwoods without causing undue harm to wildlife resources is critical. Group-selection silviculture involves harvesting a small group of trees, which creates a canopy gap (usually

  4. Impacts of timber harvesting on soil organic matter, nitrogen, productivity, and health of inland northwest forests

    Science.gov (United States)

    M. F. Jurgensen; A. E. Harvey; R. T. Graham; D. S. Page-Dumroese; J. R. Tonn; M. J. Larsen; T. B. Jain

    1997-01-01

    Soil organic components are important factors in the health and productivity of Inland Northwest forests. Timber harvesting and extensive site preparation (piling, windrowing, or scalping) reduces the amount of surface organic material (woody residues and forest floor layers) over large areas. Some wildfires and severe prescribed burns can have similar consequences....

  5. Potential effects of timber harvest and water management on streamflow dynamics and sediment transport

    Science.gov (United States)

    C. A. Troendle; W. K. Olsen

    1994-01-01

    The sustainability of aquatic and riparian ecological systems is strongly tied to the dynamics of the streamflow regime. Timber harvest can influence the flow regime by increasing total flow, altering peak discharge rate, and changing the duration of flows of differing frequency of occurrence. These changes in the energy and sediment transporting capability of the...

  6. Overview of approaches to sustain forest productivity during forest road development and timber harvesting activities

    Science.gov (United States)

    Charles R. Blinn; Rick Dahlamn; James A. Mattson; Michael A. Thompson

    1999-01-01

    Various approaches are available to minimize impacts on forest productivity during forest road building and timber harvesting activities. These approaches include a variety of practices and technologies. They include practices such as reducing road and trail development, using designated trails, and leaving slash at the stump on nutrient deficient sites. Technology...

  7. Spatial simulation of forest succession and timber harvesting using LANDIS

    Science.gov (United States)

    Eric J. Gustafson; Stephen R. Shifley; David J. Mladenoff; Kevin K. Nimerfro; Hong S. He

    2000-01-01

    The LANDIS model simulates ecological dynamics, including forest succession, disturbance, seed dispersal and establishment, fire and wind disturbance, and their interactions. We describe the addition to LANDIS of capabilities to simulate forest vegetation management, including harvest. Stands (groups of cells) are prioritized for harvest using one of four ranking...

  8. Investigation of timber harvesting mechanization progress in Turkey ...

    African Journals Online (AJOL)

    Log in or Register to get access to full text downloads. ... of substantial number of harvesters, the amount of modern harvesting processor in Turkey is not sufficient. Different type and marked machines have not been taken into consideration to ...

  9. Managing the forest for more than the trees: effects of experimental timber harvest on forest Lepidoptera.

    Science.gov (United States)

    Summerville, Keith S

    2011-04-01

    Studies of the effects of timber harvest on forest insect communities have rarely considered how disturbance from a range of harvest levels interacts with temporal variation in species diversity to affect community resistance to change. Here I report the results of a landscape-scale, before-and-after, treatment-control experiment designed to test how communities of forest Lepidoptera experience (1) changes in species richness and composition and (2) shifts in species dominance one year after logging. I sampled Lepidoptera from 20 forest stands allocated to three harvest treatments (control, even-aged shelterwood or clearcuts, and uneven-aged group selection cuts) within three watersheds at Morgan-Monroe State Forest, Indiana, USA. Moths were sampled from all forest stands one year prior to harvest in 2007 and immediately post-harvest in 2009. Species composition was most significantly affected by temporal variation between years, although uneven-aged management also caused significant changes in lepidopteran community structure. Furthermore, species richness of Lepidoptera was higher in 2007 compared to 2009 across all watersheds and forest stands. The decrease in species richness between years, however, was much larger in even-aged and uneven-aged management units compared to the control. Furthermore, matrix stands within the even-aged management unit demonstrated the highest resistance to species loss within any management unit. Species dominance was highly resistant to effects of timber harvest, with pre- and post-harvest values for Simpson diversity nearly invariant. Counter to prediction, however, the suite of dominant taxa differed dramatically among the three management units post-harvest. My results suggest that temporal variation may have strong interactions with timber harvest, precipitating loss of nearly 50% species richness from managed stands regardless of harvest level. Even-aged management, however, appeared to leave the smallest "footprint" on moth

  10. A computer-based time study system for timber harvesting operations

    Science.gov (United States)

    Jingxin Wang; Joe McNeel; John Baumgras

    2003-01-01

    A computer-based time study system was developed for timber harvesting operations. Object-oriented techniques were used to model and design the system. The front-end of the time study system resides on the MS Windows CE and the back-end is supported by MS Access. The system consists of three major components: a handheld system, data transfer interface, and data storage...

  11. Utilization of Oregon’s timber harvest and associated direct economic effects.

    Science.gov (United States)

    Krista M. Gebert; Charles E. Keegan; Sue Willits; Al. Chase

    2002-01-01

    With more than 16 million acres of commercial timberland, Oregon’s forest products industry is an important part of Oregon’s economy and a major player in the Nation’s wood products market. Despite declining production over the last decade, in 1998 Oregon was still the leading producer of softwood lumber and plywood in the United States, and the timber harvested in...

  12. Timber harvest as the predominant disturbance regime in northeastern U.S. forests: Effects of harvest intensification

    Science.gov (United States)

    Brown, Michelle L.; Canham, Charles D.; Murphy, Lora; Donovan, Therese M.

    2018-01-01

    Harvesting is the leading cause of adult tree mortality in forests of the northeastern United States. While current rates of timber harvest are generally sustainable, there is considerable pressure to increase the contribution of forest biomass to meet renewable energy goals. We estimated current harvest regimes for different forest types and regions across the U.S. states of New York, Vermont, New Hampshire, and Maine using data from the U.S. Forest Inventory and Analysis Program. We implemented the harvest regimes in SORTIE‐ND, an individual‐based model of forest dynamics, and simulated the effects of current harvest regimes and five additional harvest scenarios that varied by harvest frequency and intensity over 150 yr. The best statistical model for the harvest regime described the annual probability of harvest as a function of forest type/region, total plot basal area, and distance to the nearest improved road. Forests were predicted to increase in adult aboveground biomass in all harvest scenarios in all forest type and region combinations. The magnitude of the increase, however, varied dramatically—increasing from 3% to 120% above current landscape averages as harvest frequency and intensity decreased. The variation can be largely explained by the disproportionately high harvest rates estimated for Maine as compared with the rest of the region. Despite steady biomass accumulation across the landscape, stands that exhibited old‐growth characteristics (defined as ≥300 metric tons of biomass/hectare) were rare (8% or less of stands). Intensified harvest regimes had little effect on species composition due to widespread partial harvesting in all scenarios, resulting in dominance by late‐successional species over time. Our analyses indicate that forest biomass can represent a sustainable, if small, component of renewable energy portfolios in the region, although there are tradeoffs between carbon sequestration in forest biomass and sustainable

  13. Modeling the complex impacts of timber harvests to find optimal management regimes for Amazon tidal floodplain forests

    Science.gov (United States)

    Fortini, Lucas B.; Cropper, Wendell P.; Zarin, Daniel J.

    2015-01-01

    At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region’s ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

  14. Effects of timber harvest on structural diversity and species composition in hardwood forests

    Directory of Open Access Journals (Sweden)

    FARZAM TAVANKAR

    2015-04-01

    Full Text Available Tavankar F, Bonyad AE. 2015. Effects of timber harvest on structural diversity and species composition in hardwood forests. Biodiversitas 16: 1-9. Forest management leads to changes in structure and species composition of stands. In this research vertical and horizontal structure and species composition were compared in two harvested and protected stands in the Caspian forest of Iran. The results indicated the tree and seedling density, total basal area and stand volume was significantly (P < 0.01 higher in the protected stand. The Fagus orientalis L. had the most density and basal area in the both stands. Species importance value (SIV of Fagus orientalis in the protected stand (92.5 was higher than in the harvested stand (88.5. While, the SIV of shade-intolerant tree species such as Acer insigne, Acer cappadocicum and Alnus subcordata was higher in the harvested stand. The density of trees and seedling of rare tree species, such as Ulmus glabra, Tilia begonifolia, Zelkova caprinifolia and Fraxinus coriarifolia, was also higher in the protected stand. The Shannon-Wiener diversity index in the protected stand (0.84 was significantly higher (P < 0.01 than in the harvested stand (0.72. The highest diversity value in the harvested stand was observed in DBH of 10-40 cm class, while DBH of 40-70 cm had the highest diversity value in the protected stand.

  15. Evaluating carbon storage, timber harvest, and habitat possibilities for a Western Cascades (USA) forest landscape.

    Science.gov (United States)

    Kline, Jeffrey D; Harmon, Mark E; Spies, Thomas A; Morzillo, Anita T; Pabst, Robert J; McComb, Brenda C; Schnekenburger, Frank; Olsen, Keith A; Csuti, Blair; Vogeler, Jody C

    2016-10-01

    Forest policymakers and managers have long sought ways to evaluate the capability of forest landscapes to jointly produce timber, habitat, and other ecosystem services in response to forest management. Currently, carbon is of particular interest as policies for increasing carbon storage on federal lands are being proposed. However, a challenge in joint production analysis of forest management is adequately representing ecological conditions and processes that influence joint production relationships. We used simulation models of vegetation structure, forest sector carbon, and potential wildlife habitat to characterize landscape-level joint production possibilities for carbon storage, timber harvest, and habitat for seven wildlife species across a range of forest management regimes. We sought to (1) characterize the general relationships of production possibilities for combinations of carbon storage, timber, and habitat, and (2) identify management variables that most influence joint production relationships. Our 160 000-ha study landscape featured environmental conditions typical of forests in the Western Cascade Mountains of Oregon (USA). Our results indicate that managing forests for carbon storage involves trade-offs among timber harvest and habitat for focal wildlife species, depending on the disturbance interval and utilization intensity followed. Joint production possibilities for wildlife species varied in shape, ranging from competitive to complementary to compound, reflecting niche breadth and habitat component needs of species examined. Managing Pacific Northwest forests to store forest sector carbon can be roughly complementary with habitat for Northern Spotted Owl, Olive-sided Flycatcher, and red tree vole. However, managing forests to increase carbon storage potentially can be competitive with timber production and habitat for Pacific marten, Pileated Woodpecker, and Western Bluebird, depending on the disturbance interval and harvest intensity chosen

  16. Optimizing continuous cover management of boreal forest when timber prices and tree growth are stochastic

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    Timo Pukkala

    2015-03-01

    Full Text Available Background Decisions on forest management are made under risk and uncertainty because the stand development cannot be predicted exactly and future timber prices are unknown. Deterministic calculations may lead to biased advice on optimal forest management. The study optimized continuous cover management of boreal forest in a situation where tree growth, regeneration, and timber prices include uncertainty. Methods Both anticipatory and adaptive optimization approaches were used. The adaptive approach optimized the reservation price function instead of fixed cutting years. The future prices of different timber assortments were described by cross-correlated auto-regressive models. The high variation around ingrowth model was simulated using a model that describes the cross- and autocorrelations of the regeneration results of different species and years. Tree growth was predicted with individual tree models, the predictions of which were adjusted on the basis of a climate-induced growth trend, which was stochastic. Residuals of the deterministic diameter growth model were also simulated. They consisted of random tree factors and cross- and autocorrelated temporal terms. Results Of the analyzed factors, timber price caused most uncertainty in the calculation of the net present value of a certain management schedule. Ingrowth and climate trend were less significant sources of risk and uncertainty than tree growth. Stochastic anticipatory optimization led to more diverse post-cutting stand structures than obtained in deterministic optimization. Cutting interval was shorter when risk and uncertainty were included in the analyses. Conclusions Adaptive optimization and management led to 6%–14% higher net present values than obtained in management that was based on anticipatory optimization. Increasing risk aversion of the forest landowner led to earlier cuttings in a mature stand. The effect of risk attitude on optimization results was small.

  17. Oregon’s forest products industry and timber harvest, 2008: industry trends and impacts of the Great Recession through 2010

    Science.gov (United States)

    Charles B. Gale; Charles E. Keegan; Erik C. Berg; Jean Daniels; Glenn A. Christensen; Colin B. Sorenson; Todd A. Morgan; Paul. Polzin

    2012-01-01

    This report traces the flow of Oregon’s 2008 timber harvest through the primary timber processing industry and provides a description of the structure, operation, and condition of Oregon’s forest products industry as a whole. It is the second in a series of reports that update the status of the industry every 5 years. Based on a census conducted in 2009 and 2010, we...

  18. Harvesting and consumption of fuel and timber wood in rural area of district tank, pakistan

    International Nuclear Information System (INIS)

    Badshah, L.; Hussain, F.; Burni, T.

    2014-01-01

    The study revealed that 90% of the rural people with different age group of District Tank, Pakistan depended upon firewood for catering. The total annual wood consumption for fueling by brick brewers, food sellers and domestic utilization was 18371 metric tons in this remote region. The saw machines also convert 13650 metric tons of timber wood yearly into logs and boards of various grades. The total wood consumption exceeds the quantity of wood harvested by tree fellers, farmers and wood sellers. Therefore the balance of over 13000 metric tons is sourced from neighboring forest of Tehsil Kulachi and Dera Ismail Khan. The quantity of wood removed and consumed for various purposes did not show a significant difference at (0.05) among the six locations. However student t-test showed significant difference existed in the mean annual removal and consumption of wood in the area. The study also enumerated Acacia nilotica, Tamarix aphylla, and Sueda fruticosa as the best and preferred fuel species. While Acacia nilotica, Prosopis farcta and Dalbergia sisso as the frequently used timber species in the region. The criterion of firewood and lumber consumption was very conventional like durability in blaze and opposed to termite. Consequently, it is recommended scientific vegetation conservation strategies meant at improved burning of fuel wood and maximized used of timber products as a complimentary efforts to enforced tree planting for conservation of plant resources. (author)

  19. Browsing Patterns of White-Tailed Deer Following Increased Timber Harvest and a Decline in Population Density

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    Shawn M. Crimmins

    2010-01-01

    Full Text Available We examined browsing patterns of white-tailed deer (Odocoileus virginianus on a site in the central Appalachians that experienced a substantial (>50% reduction in deer population density and an increase in the amount of timber harvest since 2001. We sampled woody browse in and immediately adjacent to 12 clearcuts ranging in age from 0–5 years postharvest in summer 2007. Clearcut-interior areas had higher woody browse abundance and browsing rates than clearcut-edge or mature forest areas. Woody browse abundance was slightly higher within individual clearcuts than in 2001 at higher population densities and lower timber harvest rates. Overall browsing rates declined from approximately 17% in 2001 to less than 5% during our study, suggesting that the combination of deer population control, and increasing the amount of timber harvest across the landscape can reduce herbivory to levels that may not impede growth and survival of forest vegetation.

  20. Avian response to timber harvesting applied experimentally to manage Cerulean Warbler breeding populations

    Science.gov (United States)

    Sheehan, James; Wood, Petra Bohall; Buehler, David A.; Keyser, Patrick D.; Larkin, Jeffrey L.; Rodewald, Amanda D.; Wigley, T. Bently; Boves, Than J.; George, Gregory A.; Bakermans, Marja H.; Beachy, Tiffany A.; Evans, Andrea; McDermott, Molly E.; Newell, Felicity L.; Perkins, Kelly A.; White, Matthew

    2014-01-01

    Timber harvesting has been proposed as a management tool to enhance breeding habitat for the Cerulean Warbler (Setophaga cerulea), a declining Neotropical–Nearctic migratory songbird that nests in the canopy of mature eastern deciduous forests. To evaluate how this single-species management focus might fit within an ecologically based management approach for multiple forest birds, we performed a manipulative experiment using four treatments (three intensities of timber harvests and an unharvested control) at each of seven study areas within the core Cerulean Warbler breeding range. We collected pre-harvest (one year) and post-harvest (four years) data on the territory density of Cerulean Warblers and six additional focal species, avian community relative abundance, and several key habitat variables. We evaluated the avian and habitat responses across the 3–32 m2 ha−1 residual basal area (RBA) range of the treatments. Cerulean Warbler territory density peaked with medium RBA (∼16 m2 ha−1). In contrast, territory densities of the other focal species were negatively related to RBA (e.g., Hooded Warbler [Setophaga citrina]), were positively related to RBA (e.g., Ovenbird [Seiurus aurocapilla]), or were not sensitive to this measure (Scarlet Tanager [Piranga olivacea]). Some species (e.g., Hooded Warbler) increased with time post-treatment and were likely tied to a developing understory, whereas declines (e.g., Ovenbird) were immediate. Relative abundance responses of additional species were consistent with the territory density responses of the focal species. Across the RBA gradient, greatest separation in the avian community was between early successional forest species (e.g., Yellow-breasted Chat [Icteria virens]) and closed-canopy mature forest species (e.g., Ovenbird), with the Cerulean Warbler and other species located intermediate to these two extremes. Overall, our results suggest that harvests within 10–20 m2 ha−1 RBA yield the largest

  1. Insights from a harvest trip model for non-timber forest products in the interior of Alaska

    Science.gov (United States)

    Kimberley Maher; Joseph Little; Patricia A. Champ

    2013-01-01

    The harvest of non-timber forest products (NTFP) for personal uses such as hobbies and handicrafts, cooking and canning, and recreation is an important pursuit for many residents in Alaska (Pilz and others 2006). Five categories of NTFP have been designated by the United Nations Food and Agricultural Organization: (1) foods; (2) medicinal plants; (3) floral greenery...

  2. Wild Harvests from Scottish Woodlands Social, cultural and economic values of contemporary non-timber forest products

    Science.gov (United States)

    Marla Emery; Suzanne Martin; Alison Dyke; Alison Dyke

    2006-01-01

    More than 30 people were interviewed about the wild edibles, medicinals, and craft materials they collect and the part that collecting plays in their lives as part of the Wild Harvests from Scottish Woodlands project. Interviews were conducted in autumn 2004. Collecting non-timber forest products (NTFPs) is a source of joy and satisfaction for many of those interviewed...

  3. The 1993 timber assessment market model: structure, projections, and policy simulations.

    Science.gov (United States)

    Darius M. Adams; Richard W. Haynes

    1996-01-01

    The 1993 timber assessment market model (TAMM) is a spatial model of the solidwood and timber inventory elements of the U.S. forest products sector. The TAMM model provides annual projections of volumes and prices in the solidwood products and sawtimber stumpage markets and estimates of total timber harvest and inventory by geographic region for periods of up to 50...

  4. Quantifying ratios of suspended sediment sources in forested headwater streams following timber-harvesting operations

    Science.gov (United States)

    Rachels, A. A.; Bladon, K. D.; Bywater-Reyes, S.

    2017-12-01

    Historically, timber-harvesting has increased fine sediment inputs to streams due to increased hillslope and streambank erosion and mass wasting along roads. However, under modern best management practices, the relative importance and variability of these sources is poorly understood. We present preliminary results from an ongoing study investigating the primary sources of suspended sediment in Oregon Coast Range streams influenced by timber harvesting. We instrumented two catchments, Enos Creek (harvested 2016) and Scheele Creek (reference) in fall 2016. Phillips samplers (5-6 per catchment) have been deployed longitudinally down the streams to enable robust characterization of suspended sediments—the collected samples integrate the chemical signatures of upstream sediment exports. We will collect samples monthly over 2 wet seasons and return to the laboratory to analyze the sediment using source fingerprinting approaches. The fingerprinting technique compares the chemical properties of stream sediment samples with the chemical properties of potential source areas, including 1) roads, 2) stream banks, and 3) hillslopes. To design a robust model for sediment-source identification, different types of chemical data are required—we will analyze sediment samples using a combination of: a) stable isotopes and C/N ratios (i.e., δ15N, δ13C, and C/N), b) geochemistry (Fe, K, and Ca), and c) radiogenic isotopes (137Cs and 210Pb). At the harvested site, the C/N ratios of the streambanks (17.9 ± 3.8) and the hillslopes (26.4 ± 4.8) are significantly different from one another (p = .016). C/N ratios of the suspended sediment (20.5 ± 2.0) are intermediate values between potential endmembers and behave conservatively with transport. The C/N ratios of the suspended sediment appear unaffected by roads (18.9 ± 8.7) along specific sections of the stream, suggesting that roads are not a primary sediment contributor. Under this assumption, the suspended sediment is, on

  5. Response of a tropical tree to non-timber forest products harvest and reduction in habitat size

    Science.gov (United States)

    Kouagou, M’Mouyohoun; Natta, Armand K.; Gado, Choukouratou

    2017-01-01

    Non-timber forest products (NTFPs) are widely harvested by local people for their livelihood. Harvest often takes place in human disturbed ecosystems. However, our understanding of NTFPs harvesting impacts in fragmented habitats is limited. We assessed the impacts of fruit harvest, and reduction in habitat size on the population structures of Pentadesma butyracea Sabine (Clusiaceae) across two contrasting ecological regions (dry vs. moist) in Benin. In each region, we selected three populations for each of the three fruit harvesting intensities (low, medium and high). Harvesting intensities were estimated as the proportion of fruits harvested per population. Pentadesma butyracea is found in gallery forests along rivers and streams. We used the width of gallery forests as a measure of habitat size. We found negative effects of fruit harvest on seedling and adult density but no significant effect on population size class distribution in both ecological regions. The lack of significant effect of fruit harvest on population structure may be explained by the ability of P. butyracea to compensate for the negative effect of fruit harvesting by increasing clonal reproduction. Our results suggest that using tree density and population structure to assess the ecological impacts of harvesting clonal plants should be done with caution. PMID:28850624

  6. Response of a tropical tree to non-timber forest products harvest and reduction in habitat size.

    Directory of Open Access Journals (Sweden)

    Orou G Gaoue

    Full Text Available Non-timber forest products (NTFPs are widely harvested by local people for their livelihood. Harvest often takes place in human disturbed ecosystems. However, our understanding of NTFPs harvesting impacts in fragmented habitats is limited. We assessed the impacts of fruit harvest, and reduction in habitat size on the population structures of Pentadesma butyracea Sabine (Clusiaceae across two contrasting ecological regions (dry vs. moist in Benin. In each region, we selected three populations for each of the three fruit harvesting intensities (low, medium and high. Harvesting intensities were estimated as the proportion of fruits harvested per population. Pentadesma butyracea is found in gallery forests along rivers and streams. We used the width of gallery forests as a measure of habitat size. We found negative effects of fruit harvest on seedling and adult density but no significant effect on population size class distribution in both ecological regions. The lack of significant effect of fruit harvest on population structure may be explained by the ability of P. butyracea to compensate for the negative effect of fruit harvesting by increasing clonal reproduction. Our results suggest that using tree density and population structure to assess the ecological impacts of harvesting clonal plants should be done with caution.

  7. Productivity assessment of timber harvesting techniques for supporting sustainable forest management of secondary Atlantic Forests in southern Brazil

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    Pedro Caldas Britto

    2017-12-01

    Full Text Available The Atlantic Forest in southern Brazil has been subject to overexploitation in the past prompting the formulation of a rigorous conservation orientated policy by the government including a strict ban of timber harvesting. In the region, the forestland is owned by farmers. The economic value of the forest is rather limited for those farmers, because of the prohibition of commercial timber harvesting as a source of income. Sustainable forest management systems can offer great potential as new income opportunities for land holders, and further actively support the process of ecosystem rehabilitation and protection for these ecosystems. Yet, successful implementation of such sustainable management systems requires feasible and adapted timber harvesting systems. In order to develop such harvesting systems, a regional comparative case study was conducted at a typical smallholder forestry venture with the objective to analyze and evaluate harvesting methods supporting sustainable management of the Atlantic Forest. This study assessed production rates and associated costs of a common conventional timber harvesting method (CM and a proposed alternative method (AM. CM was performed by a selected, typical forest landowner who had only basic training in chainsaw operations, but 20 years of experience at the wood yard of his small sawmill. In contrast, the AM employed a professional chainsaw operator from the Amazon forest, trained and experienced in reduced impact logging techniques using state of the art equipment, supplemented by a snatch block and a skidding cone for improved extraction. Time study based models identified tree volume, winching distance and skidding distance to the landing as the most significant independent variables affecting productivity. Total net productivity ranged from 4.9 m³ PMH0-1 for CM to 3.1 m³ PMH0-1 for AM. Corresponding gross-productivity ranged from 3.0 m³ SMH-1 to 1.9 m³ SMH-1 with an overall mean utilization rate of

  8. Aquatic ecosystem response to timber harvesting for the purpose of restoring aspen.

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    Bobette E Jones

    Full Text Available The removal of conifers through commercial timber harvesting has been successful in restoring aspen, however many aspen stands are located near streams, and there are concerns about potential aquatic ecosystem impairment. We examined the effects of management-scale conifer removal from aspen stands located adjacent to streams on water quality, solar radiation, canopy cover, temperature, aquatic macroinvertebrates, and soil moisture. This 8-year study (2003-2010 involved two projects located in Lassen National Forest. The Pine-Bogard Project consisted of three treatments adjacent to Pine and Bogard Creeks: (i Phase 1 in January 2004, (ii Phase 2 in August 2005, and (iii Phase 3 in January 2008. The Bailey Project consisted of one treatment adjacent to Bailey Creek in September 2006. Treatments involved whole tree removal using track-laying harvesters and rubber tire skidders. More than 80% of all samples analyzed for NO₃-N, NH₄-N, and PO₄-P at Pine, Bogard, and Bailey Creeks were below the detection limit, with the exception of naturally elevated PO₄-P in Bogard Creek. All nutrient concentrations (NO₃-N, NH₄-N, PO₄-P, K, and SO₄-S showed little variation within streams and across years. Turbidity and TSS exhibited annual variation, but there was no significant increase in the difference between upstream and downstream turbidity and TSS levels. There was a significant decrease in stream canopy cover and increase in the potential fraction of solar radiation reaching the streams in response to the Pine-Bogard Phase 3 and Bailey treatments; however, there was no corresponding increase in stream temperatures. Macroinvertebrate metrics indicated healthy aquatic ecosystem conditions throughout the course of the study. Lastly, the removal of vegetation significantly increased soil moisture in treated stands relative to untreated stands. These results indicate that, with careful planning and implementation of site-specific best management

  9. Biogeography and organic matter removal shape long-term effects of timber harvesting on forest soil microbial communities.

    Science.gov (United States)

    Wilhelm, Roland C; Cardenas, Erick; Maas, Kendra R; Leung, Hilary; McNeil, Larisa; Berch, Shannon; Chapman, William; Hope, Graeme; Kranabetter, J M; Dubé, Stephane; Busse, Matt; Fleming, Robert; Hazlett, Paul; Webster, Kara L; Morris, David; Scott, D Andrew; Mohn, William W

    2017-11-01

    The growing demand for renewable, carbon-neutral materials and energy is leading to intensified forest land-use. The long-term ecological challenges associated with maintaining soil fertility in managed forests are not yet known, in part due to the complexity of soil microbial communities and the heterogeneity of forest soils. This study determined the long-term effects of timber harvesting, accompanied by varied organic matter (OM) removal, on bacterial and fungal soil populations in 11- to 17-year-old reforested coniferous plantations at 18 sites across North America. Analysis of highly replicated 16 S rRNA gene and ITS region pyrotag libraries and shotgun metagenomes demonstrated consistent changes in microbial communities in harvested plots that included the expansion of desiccation- and heat-tolerant organisms and decline in diversity of ectomycorrhizal fungi. However, the majority of taxa, including the most abundant and cosmopolitan groups, were unaffected by harvesting. Shifts in microbial populations that corresponded to increased temperature and soil dryness were moderated by OM retention, which also selected for sub-populations of fungal decomposers. Biogeographical differences in the distribution of taxa as well as local edaphic and environmental conditions produced substantial variation in the effects of harvesting. This extensive molecular-based investigation of forest soil advances our understanding of forest disturbance and lays the foundation for monitoring long-term impacts of timber harvesting.

  10. Policy Effectiveness of Loan for Delaying Timber Harvesting for Smallholder Private Forest in Indonesia

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    Bramasto Nugroho

    2017-08-01

    Full Text Available This study aimed to analyze policy effectiveness of loan for delaying timber harvesting for smallholder private forest business (Pinjaman Tunda Tebang Hutan Rakyat; hereinafter will be referred as PTT-HR. The analysis will be used to provide recommendations for improving PTT-HR scheme included scaling out and scaling up of the scheme for improving economic benefits and supporting smallholder private forest business as well as for strengthening farmer's welfare. Field survey was conducted in October–November 2013 in two districts in Central of Java, Indonesia namely Blora and Wonosobo District as recipient of PTT-HR from Public Service Agency for Forest Development Financing Center (BLU Center of P2H Ministry of Forestry, Republic of Indonesia. The results showed that PTT-HR policy has implemented effectively based on evaluation parameter derived from the objectives of policy namely the age of the stands for loan collateral, the capabilities for improving farmer's welfare, utilization of loan, perception of the farmers regarding to the ease of the process and purpose of loan utilization, and the capability of loan repayment. However, this research has not been answered the aspect of PTT-HR policy implementation efficiency

  11. Forest bat population dynamics over 14 years at a climate refuge: Effects of timber harvesting and weather extremes.

    Science.gov (United States)

    Law, Bradley S; Chidel, Mark; Law, Peter R

    2018-01-01

    Long-term data are needed to explore the interaction of weather extremes with habitat alteration; in particular, can 'refugia' buffer population dynamics against climate change and are they robust to disturbances such as timber harvesting. Because forest bats are good indicators of ecosystem health, we used 14 years (1999-2012) of mark-recapture data from a suite of small tree-hollow roosting bats to estimate survival, abundance and body condition in harvested and unharvested forest and over extreme El Niño and La Niña weather events in southeastern Australia. Trapping was replicated within an experimental forest, located in a climate refuge, with different timber harvesting treatments. We trapped foraging bats and banded 3043 with a 32% retrap rate. Mark-recapture analyses allowed for dependence of survival on time, species, sex, logging treatment and for transients. A large portion of the population remained resident, with a maximum time to recapture of nine years. The effect of logging history (unlogged vs 16-30 years post-logging regrowth) on apparent survival was minor and species specific, with no detectable effect for two species, a positive effect for one and negative for the other. There was no effect of logging history on abundance or body condition for any of these species. Apparent survival of residents was not strongly influenced by weather variation (except for the smallest species), unlike previous studies outside of refugia. Despite annual variation in abundance and body condition across the 14 years of the study, no relationship with extreme weather was evident. The location of our study area in a climate refuge potentially buffered bat population dynamics from extreme weather. These results support the value of climate refugia in mitigating climate change impacts, though the lack of an external control highlights the need for further studies on the functioning of climate refugia. Relatively stable population dynamics were not compromised by

  12. Assessment of Streamside Management Zones for Conserving Benthic Macroinvertebrate Communities Following Timber Harvest in Eastern Kentucky Headwater Catchments

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    Joshua K. Adkins

    2016-06-01

    Full Text Available Headwater streams generally comprise the majority of stream area in a watershed and can have a strong influence on downstream food webs. Our objective was to determine the effect of altering streamside management zone (SMZ configurations on headwater aquatic insect communities. Timber harvests were implemented within six watersheds in eastern Kentucky. The SMZ configurations varied in width, canopy retention and best management practice (BMP utilization at the watershed scale. Benthic macroinvertebrate samples collected one year before and four years after harvest indicated few differences among treatments, although post-treatment abundance was elevated in some of the treatment streams relative to the unharvested controls. Jaccard index values were similar across SMZ treatments after logging, indicating strong community overlap. These findings suggest that stream invertebrate communities did respond to the timber harvest, though not negatively. Results also suggest that SMZ criteria for aquatic habitats in steeply sloping topography, including at least 50 percent canopy retention and widths of at least 16.8 m, appear to be adequate for protecting benthic macroinvertebrate communities from logging impacts.

  13. Effects of timber harvest on phlebotomine sand flies (Diptera: Psychodidae in a production forest: abundance of species on tree trunks and prevalence of trypanosomatids

    Directory of Open Access Journals (Sweden)

    Felipe Arley Costa Pessoa

    2007-08-01

    Full Text Available The Amazon forest is being exploited for timber production. The harvest removes trees, used by sand flies as resting sites, and decreases the canopy, used as refuges by some hosts. The present study evaluated the impact of the timber harvest, the abundance of sand flies, and their trypanosomatid infection rates before and after selective logging. The study was accomplished in terra-firme production forest in an area of timber harvest, state of Amazonas, Brazil. Sand fly catches were carried out in three areas: one before and after the timber harvest, and two control areas, a nature preservation area and a previously exploited area. The flies were caught by aspiration on tree trunks. Samples of sand flies were dissected for parasitological examination. In the site that suffered a harvest, a larger number of individuals was caught before the selective extraction of timber, showing significant difference in relation to the number of individuals and their flagellate infection rates after the logging. The other two areas did not show differences among their sand fly populations. This fact is suggestive of a fauna sensitive to the environmental alterations associated with selective logging.

  14. Forest bat population dynamics over 14 years at a climate refuge: Effects of timber harvesting and weather extremes.

    Directory of Open Access Journals (Sweden)

    Bradley S Law

    Full Text Available Long-term data are needed to explore the interaction of weather extremes with habitat alteration; in particular, can 'refugia' buffer population dynamics against climate change and are they robust to disturbances such as timber harvesting. Because forest bats are good indicators of ecosystem health, we used 14 years (1999-2012 of mark-recapture data from a suite of small tree-hollow roosting bats to estimate survival, abundance and body condition in harvested and unharvested forest and over extreme El Niño and La Niña weather events in southeastern Australia. Trapping was replicated within an experimental forest, located in a climate refuge, with different timber harvesting treatments. We trapped foraging bats and banded 3043 with a 32% retrap rate. Mark-recapture analyses allowed for dependence of survival on time, species, sex, logging treatment and for transients. A large portion of the population remained resident, with a maximum time to recapture of nine years. The effect of logging history (unlogged vs 16-30 years post-logging regrowth on apparent survival was minor and species specific, with no detectable effect for two species, a positive effect for one and negative for the other. There was no effect of logging history on abundance or body condition for any of these species. Apparent survival of residents was not strongly influenced by weather variation (except for the smallest species, unlike previous studies outside of refugia. Despite annual variation in abundance and body condition across the 14 years of the study, no relationship with extreme weather was evident. The location of our study area in a climate refuge potentially buffered bat population dynamics from extreme weather. These results support the value of climate refugia in mitigating climate change impacts, though the lack of an external control highlights the need for further studies on the functioning of climate refugia. Relatively stable population dynamics were not

  15. Harvest, employment, exports, and prices in Pacific Northwest forests, 1965-2010

    Science.gov (United States)

    Debra D. Warren

    2011-01-01

    Provides historical information on log harvest; employment in the forest industries; international trade in logs, lumber, and chips; and volume and average prices of sawtimber stumpage sold by national forests.

  16. A detrimental soil disturbance prediction model for ground-based timber harvesting

    Science.gov (United States)

    Derrick A. Reeves; Matthew C. Reeves; Ann M. Abbott; Deborah S. Page-Dumroese; Mark D. Coleman

    2012-01-01

    Soil properties and forest productivity can be affected during ground-based harvest operations and site preparation. The degree of impact varies widely depending on topographic features and soil properties. Forest managers who understand site-specific limits to ground-based harvesting can alter harvest method or season to limit soil disturbance. To determine the...

  17. Public Preferences for Timber Harvesting on Private Forest Land Purchased for Public Ownership in Maine

    Science.gov (United States)

    Kevin J. Boyle; Mario F. Teisl

    1999-01-01

    Public concern over the use, the management, and the protection of forests in Maine and throughout the United States has grown rapidly over the last two decades. Decisions regarding where, when, and how to cut timber are no longer purely silvicultural decisionlS made by forest managers, but are increasingly subject to public scrutiny, debate, regulation, and litigation...

  18. Effects of timber harvests on invertebrate biomass and avian nest success

    Science.gov (United States)

    Jeffrey P. Duguay; Petra Bohall Wood; Gary W. Miller

    2000-01-01

    Concerns over declining songbird populations have led to investigations of effects of various timber management practices on breeding songbirds. We assessed the influence of 2 types of practices, two-age and clearcutting, on invertebrate biomass and avian daily nest survival in the Monongahela National Forest of West Virginia during summers of 1995 and 1996. We also...

  19. "Keeping it Living": applications and relevance of traditional plant management in British Columbia to sustainable harvesting of non-timber forest products

    Science.gov (United States)

    Nancy J. Turner

    2001-01-01

    There has been increasing concern about sustainability in harvesting and marketing of non-timber forest products in North America. This paper examines traditional approaches and practices for use of plant resources by Aboriginal peoples and discusses their applications in a contemporary context. Philosophies and attitudes of caring and respect are embodied in many...

  20. Turbidity Responses from Timber Harvesting, Wildfire, and Post-Fire Logging in the Battle Creek Watershed, Northern California.

    Science.gov (United States)

    Lewis, Jack; Rhodes, Jonathan J; Bradley, Curtis

    2018-04-11

    The Battle Creek watershed in northern California was historically important for its Chinook salmon populations, now at remnant levels due to land and water uses. Privately owned portions of the watershed are managed primarily for timber production, which has intensified since 1998, when clearcutting became widespread. Turbidity has been monitored by citizen volunteers at 13 locations in the watershed. Approximately 2000 grab samples were collected in the 5-year analysis period as harvesting progressed, a severe wildfire burned 11,200 ha, and most of the burned area was salvage logged. The data reveal strong associations of turbidity with the proportion of area harvested in watersheds draining to the measurement sites. Turbidity increased significantly over the measurement period in 10 watersheds and decreased at one. Some of these increases may be due to the influence of wildfire, logging roads and haul roads. However, turbidity continued trending upwards in six burned watersheds that were logged after the fire, while decreasing or remaining the same in two that escaped the fire and post-fire logging. Unusually high turbidity measurements (more than seven times the average value for a given flow condition) were very rare (0.0% of measurements) before the fire but began to appear in the first year after the fire (5.0% of measurements) and were most frequent (11.6% of measurements) in the first 9 months after salvage logging. Results suggest that harvesting contributes to road erosion and that current management practices do not fully protect water quality.

  1. A Spatially Explicit Method to Assess the Economic Suitability of a Forest Road Network for Timber Harvest in Steep Terrain

    Directory of Open Access Journals (Sweden)

    Leo Gallus Bont

    2018-03-01

    Full Text Available Despite relatively high road density in the forests of Switzerland, a large percentage of that road network does not fulfill best practice requirements. Before upgrading or rebuilding the road network, harvesting planners must first determine which areas have insufficient access. Traditional assessment methods tend to only report specific values such as road density. However, those values do not identify the exact parcels or areas that are inaccessible. Here, we present a model that assesses the economic suitability of each timbered parcel for wood-harvesting operations, including tree-felling and processing, and off- and on-road transport (hauling, based on the existing road network. The entire wood supply chain from forest (standing trees to a virtual pile at the border of the planning unit was captured. This method was particularly designed for steep terrain and was tested in the Canton of Grisons in Switzerland. Compared with classical approaches, such as the road density concept, which only deliver average values, this new method enables planners to assess the development of a road network in a spatially explicit manner and to easily identify the reason and the location of shortcomings in the road network. Moreover, while other related spatially explicit approaches focus only on harvesting operations, the assessment method proposed here also includes limitations (road standards of the road network.

  2. Risks, Information and Short-Run Timber Supply

    Directory of Open Access Journals (Sweden)

    Francesca Rinaldi

    2013-12-01

    Full Text Available Efforts to increase wood mobilization have highlighted the need to appraise drivers of short-run timber supply. The current study aims to shed further light on harvesting decisions of private forest owners, by investigating optimal harvesting under uncertainty, when timber revenues are invested on financial markets and uncertainty is mitigated by news releases. By distinguishing between aggregate economic risk and sector specific risks, the model studies in great detail optimal harvesting-investment decisions, with particular emphasis on the non-trivial transmission of risk on optimal harvesting, and on the way private forest owners react to news and information. The analysis of the role played by information in harvesting decisions is a novelty in forest economic theory. The presented model is highly relevant from a policy—information is a commonly used forest policy instrument—as well as a practical perspective, since the mechanism of risk transmission is at the basis of timber pricing.

  3. Effects of Timber Harvesting with Best Management Practices on Ecosystem Metabolism of a Low Gradient Stream on the United States Gulf Coastal Plain

    Directory of Open Access Journals (Sweden)

    Abram DaSilva

    2013-06-01

    Full Text Available Stream metabolism can be used as a measure of freshwater ecosystem health because of its responsiveness to natural and anthropogenic changes. In this study, we used stream metabolic rates to test for the effects of a timber harvest with Louisiana’s current best management practices (BMPs. The study was conducted from 2006 to 2010 in a loblolly pine (Pinus taeda stand in north-central Louisiana, USA, 45 ha of which was clear cut harvested in the summer of 2007. Dissolved oxygen (DO, water temperature, and stream depth were recorded at a site upstream (serving as a reference and a site downstream of the harvested area. Using diurnal DO change and an open-system, single-station method at each site, we quantified rates of net ecosystem productivity (NEP, gross primary productivity (GPP, community respiration (CR, and the GPP/CR ratio. The system was predominately heterotrophic, with a GPP/CR ratio of less than one for 82% of the time at the upstream site. No calculated metabolic rate was significantly changed by the timber harvest (two-way ANOVA with interaction; p < 0.001. Overall, the results suggest that timber harvests of similar intensity with Louisiana’s current BMPs may not significantly impact stream biological conditions.

  4. Esthetic evaluation of timber harvesting in the Northern Rockies - a progressive report

    Science.gov (United States)

    Dennis L. Schweitzer; James R. Ullrich; Robert E. Benson

    1976-01-01

    Panels of judges have been evaluating the esthetic dimension of harvested areas in the Northern Rockies. Studies conducted in Wyoming and Montana agree with intuition in that forest scenes are generally liked less as the evidence of man's activities increases.

  5. Influence of timber harvesting costs on the layout of cuttings and economic return in forest planning based on dynamic treatment units

    Directory of Open Access Journals (Sweden)

    Adrián Pascual

    2018-05-01

    Full Text Available Aim of study: To analyze the influence of harvesting costs on the distribution and type of cuttings when forest management planning is based on the dynamic treatment units (DTUs approach. Area of study: A Mediterranean pine forest in Central Spain. Materials and methods: Airborne laser scanning data were used in area-based approach to predict stand attributes and delineate segments that were used as calculation units. Predicted stand attributes and existing models for diameter distribution and individual-tree growth were used to simulate alternative management schedules for each segment for a 60-year planning horizon divided into three 20-year periods. Three alternative forest planning problems were formulated. They aimed to maximize or minimize net income, or maximize timber production with a constant flow of harvested timber. Spatial goals were used in all cases to enhance the clustering of treatments. Main results: Maxizing timber production without considering harvesting costs can be costly, even close to the plan that minimized net incomes. Maximizing net incomes led to frequent use of final felling instead of thinnings, placing cuttings near forest roads and creating more compact DTUs than obtained in the plan that maximized timber production. Research highlights: Compared to previous studies on DTUs, this study integrated felling and forwarding costs, which depended on distance to road and stand attributes, in the process of creating DTUs by means of spatial optimization.

  6. Collaborative Monitoring of Production and Costs of Timber Harvest Operations in the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Benno Pokorny

    2005-06-01

    Full Text Available Timber companies and policy makers in the Brazilian Amazon urgently need financial information on forest management. Results from a few experiments, case studies, and surveys have been groundbreaking, but are insufficient. A strategic partnership between timber companies and research organizations is needed to generate additional information. This paper presents a tool for monitoring production and costs of forest operations to facilitate such collaboration. The tool provides useful information for companies and, at the same time, generates reliable data for research. Selected results are presented on production, capacity, and costs to demonstrate the usefulness of the information that can be generated. These results are based on the first 2 years of implementation by a company in the State of Pará, Brazil. This pilot project confirmed that the tool is simple and relevant. Its successful implementation requires significant investment, and will be applicable only to companies interested in changing from conventional logging to reduced-impact logging, especially those seeking Forest Stewardship Council certification. Successful implementation of the tool will also depend on it generating readily understood and highly relevant results for the companies, and receiving extensive support during the first 2 years.

  7. Creating scarcity from abundance: Bumper harvests, high prices ...

    African Journals Online (AJOL)

    By purchasing majority of the maize on the market, the FRA limited the need for commercial mills to access maize directly from the market. This reduced competition in the wholesaling sector and concentrated maize supply chain around the FRA; (2) Rationing of the FRA maize sold at subsidized prices to commercial mills.

  8. Regional Changes in the Timber Resources of and Lumber Production in Pennsylvania

    Science.gov (United States)

    William G. Luppold; Matthew S. Bumgardner; Matthew S. Bumgardner

    2005-01-01

    In this study we examine regional differences in the hardwood timber resources of Pennsylvania and explain how the combined changes in this resource and in lumber prices have influenced regional lumber production. Isolation of these relationships is important because shifts in lumber production affect harvesting levels and harvesting activity influences long-term...

  9. Hydrologic and climatic changes in three small watersheds after timber harvest.

    Science.gov (United States)

    W.B. Fowler; J.D. Helvey; E.N. Felix

    1987-01-01

    No significant increases in annual water yield were shown for three small watersheds in northeastern Oregon after shelterwood cutting (30-percent canopy removal, 50-percent basal area removal) and clearcutting. Average maximum air temperature increased after harvest and average minimum air temperature decreased by up to 2.6 °C. Both maximum and minimum water...

  10. Estimated timber harvest by U.S. region and ownership, 1950-2002.

    Science.gov (United States)

    Darius M. Adams; Richard W. Haynes; Adam J. Daigneault

    2006-01-01

    This publication provides estimates of total softwood and hardwood harvests by region and owner for the United States from 1950 to 2002. These data are generally not available in a consistent fashion and have to be estimated from state-level data, forest resource inventory statistics, and production of forest products. This publication describes the estimation process...

  11. Bats of the hardwood ecosystem experiment before timber harvest: assessment and prognosis

    Science.gov (United States)

    Jeremy J. Sheets; John O. Whitaker; Virgil Jr. Brack; Dale W. Sparks

    2013-01-01

    Before experimental harvest of the Yellowwood (YW) and Morgan-Monroe (MM) State Forests (Indiana) as part of the Hardwood Ecosystem Experiment, bats were sampled using mist nets at four locations in MM and five locations in YW during each summer 2006 through 2008. Netting locations were adjacent to forest stands scheduled for experimental manipulations following...

  12. Long term effects of wet site timber harvesting and site preparation on soil properties and loblolly pine (Pinus taeda L.) productivity in the lower Atlantic Coastal Plain

    OpenAIRE

    Neaves III, Charles Mitchell

    2017-01-01

    Short term studies have suggested that ground based timber harvesting on wet sites can alter soil properties and inhibit early survival and growth of seedlings. Persistence of such negative effects may translate to losses in forest productivity over a rotation. During the fall and winter of 1989, numerous salvage logging operations were conducted during high soil moisture conditions on wet pine flats in the lower coastal plain of South Carolina following Hurricane Hugo. A long-term experim...

  13. Effects of new export rules, a spotted owl plan, and recession on timber prices and shipments from the Douglas-fir region.

    Science.gov (United States)

    Donald F. Flora; Wendy J. McGInnls

    1992-01-01

    Several recently emplaced and potential Northwest timber policies are causing considerable market turbulence. Estimated were price and volume changes induced by three supply-side policies (a state-log export embargo, forest replanning, and spotted owl reservations) and the demand slide of 1990-91. Impacts were gauged separately and together by using a four-sector model...

  14. Variability after 15 Years of Vegetation Recovery in Natural Secondary Forest with Timber Harvesting at Different Intensities in Southeastern China: Community Diversity and Stability

    Directory of Open Access Journals (Sweden)

    Zhilong Wu

    2018-01-01

    Full Text Available The mixed Cunninghamia lanceolata (Lamb. Hook., Pinus massoniana Lamb., and hardwood forest in southeastern China is a major assemblage in natural secondary forests, and of national and international importance in terms of both timber and ecosystem services. However, over-harvesting has threatened its long-term sustainability, and there is a knowledge gap relating to the effect of harvesting on the ecosystem. After conifer species were selected for harvesting, the mixed Chinese fir, pine, and hardwood forest was changed into mixed evergreen broadleaf forest. In this context, we observed the restoration dynamics of plant communities over a period of 15 years (1996 to 2011 with different levels of harvesting intensity, including selective harvesting at low (13.0% removal of growing stock volume, medium (29.1%, high (45.8%, and extra-high (67.1% intensities, as well as clear-cut harvesting (100.0%, with non-harvesting as the control, based on permanent sample plots established in a randomized block design in these forests in southeastern China. The impact on the richness, diversity, and evenness of plant species derived from descriptive statistical analyses was shown to initially increase, and then decrease, with an increase in harvesting intensity. The most critical impacts were on the richness, diversity, and evenness of shrub and herb species. Richness, diversity, and evenness of plant species recovered and increased under selective harvesting at low and medium intensities, while these parameters had not recovered and significantly decreased under selective harvesting at high and extra-high intensities, as well as with clear-cut harvesting. The impact on the plant community stability was derived from the stability test method of the improved Godron M. The plant community stability was closest to the point of stability (20/80 under selective harvesting at medium intensity, followed by selective harvesting at low intensity. The plant community

  15. Modern Timber Harvesting Practices Have Little Short-Term Effect on Soil Carbon Stores in Industrial Forests of Western Oregon and Washington, U.S.A.

    Science.gov (United States)

    Holub, S. M.; Hatten, J. A.

    2017-12-01

    Soil carbon represents a large, but slowly changing pool of carbon in forests and understanding its response to forest management, including harvesting, is critical for determining overall stand/landscape carbon balance. Past studies have observed mixed effects of harvesting on soil carbon possibly due, in part, to imprecise sampling methods and high variability within soils. Weyerhaeuser Company has led a major effort to examine the effect of conventional timber harvesting on long-term soil carbon stores in western Oregon and Washington Douglas-fir forests using a highly-replicated longitudinal study design that enables precise estimation of variability found in these systems. In 2010, we randomly selected nine harvest units from Weyerhaeuser's 2012 harvest plan. At each non-harvested unit, a uniform, non-rocky area of about 3-6 hectares was selected for the study. Pre-harvest soil samples were collected at 300 sample points from each unit on a fixed square grid, targeting an intensity that would allow detection of >5% change in soil carbon stores. We measured soil carbon concentration and soil bulk density in depth increments to 1 m to allow for the calculation of total soil carbon per hectare. Other ecosystem pools of carbon, such as trees and downed wood, also have been measured to complete the whole-site carbon budget. All units were harvested from late 2011 through mid-year 2012. In 2015, 3-3.5 years post-harvest, we resampled the same areas in an identical manner as the pre-harvest collection to evaluate changes in soil carbon following harvest. Across all sites combined, we estimated a +2% change (-2% to +6%, 95% confidence interval) in mineral soil carbon following harvest, which is consistent with small-to-no change. Individual sites varied in direction of response; only one site showed evidence of a slight decrease in soil carbon, while two sites showed slight gains. These early results indicate that Weyerhaeuser's conventional timber harvesting methods

  16. New Approach for forest inventory estimation and timber harvesting planning in mountain areas: the SLOPE project

    Science.gov (United States)

    Prandi, F.; Magliocchetti, D.; Poveda, A.; De Amicis, R.; Andreolli, M.; Devigili, F.

    2016-06-01

    Forests represent an important economic resource for mountainous areas being for a few region and mountain communities the main form of income. However, wood chain management in these contexts differs from the traditional schemes due to the limits imposed by terrain morphology, both for the operation planning aspects and the hardware requirements. In fact, forest organizational and technical problems require a wider strategic and detailed level of planning to reach the level of productivity of forest operation techniques applied on flatlands. In particular, a perfect knowledge of forest inventories improves long-term management sustainability and efficiency allowing a better understanding of forest ecosystems. However, this knowledge is usually based on historical parcel information with only few cases of remote sensing information from satellite imageries. This is not enough to fully exploit the benefit of the mountain areas forest stocks where the economic and ecological value of each single parcel depends on singletree characteristics. The work presented in this paper, based on the results of the SLOPE (Integrated proceSsing and controL systems fOr sustainable forest Production in mountain arEas) project, investigates the capability to generate, manage and visualize detailed virtual forest models using geospatial information, combining data acquired from traditional on-the-field laser scanning surveys technologies with new aerial survey through UAV systems. These models are then combined with interactive 3D virtual globes for continuous assessment of resource characteristics, harvesting planning and real-time monitoring of the whole production.

  17. New Approach for forest inventory estimation and timber harvesting planning in mountain areas: the SLOPE project

    Directory of Open Access Journals (Sweden)

    F. Prandi

    2016-06-01

    Full Text Available Forests represent an important economic resource for mountainous areas being for a few region and mountain communities the main form of income. However, wood chain management in these contexts differs from the traditional schemes due to the limits imposed by terrain morphology, both for the operation planning aspects and the hardware requirements. In fact, forest organizational and technical problems require a wider strategic and detailed level of planning to reach the level of productivity of forest operation techniques applied on flatlands. In particular, a perfect knowledge of forest inventories improves long-term management sustainability and efficiency allowing a better understanding of forest ecosystems. However, this knowledge is usually based on historical parcel information with only few cases of remote sensing information from satellite imageries. This is not enough to fully exploit the benefit of the mountain areas forest stocks where the economic and ecological value of each single parcel depends on singletree characteristics. The work presented in this paper, based on the results of the SLOPE (Integrated proceSsing and controL systems fOr sustainable forest Production in mountain arEas project, investigates the capability to generate, manage and visualize detailed virtual forest models using geospatial information, combining data acquired from traditional on-the-field laser scanning surveys technologies with new aerial survey through UAV systems. These models are then combined with interactive 3D virtual globes for continuous assessment of resource characteristics, harvesting planning and real-time monitoring of the whole production.

  18. Soil carbon storage following road removal and timber harvesting in redwood forests

    Science.gov (United States)

    Seney, Joseph; Madej, Mary Ann

    2015-01-01

    Soil carbon storage plays a key role in the global carbon cycle and is important for sustaining forest productivity. Removal of unpaved forest roads has the potential for increasing carbon storage in soils on forested terrain as treated sites revegetate and soil properties improve on the previously compacted road surfaces. We compared soil organic carbon (SOC) content at several depths on treated roads to SOC in adjacent second-growth forests and old-growth redwood forests in California, determined whether SOC in the upper 50 cm of soil varies with the type of road treatment, and assessed the relative importance of site-scale and landscape-scale variables in predicting SOC accumulation in treated road prisms and second-growth redwood forests. Soils were sampled at 5, 20, and 50 cm depths on roads treated by two methods (decommissioning and full recontouring), and in adjacent second-growth and old-growth forests in north coastal California. Road treatments spanned a period of 32 years, and covered a range of geomorphic and vegetative conditions. SOC decreased with depth at all sites. Treated roads on convex sites exhibited higher SOC than on concave sites, and north aspect sites had higher SOC than south aspect sites. SOC at 5, 20, and 50 cm depths did not differ significantly between decommissioned roads (treated 18–32 years previous) and fully recontoured roads (treated 2–12 years previous). Nevertheless, stepwise multiple regression models project higher SOC developing on fully recontoured roads in the next few decades. The best predictors for SOC on treated roads and in second-growth forest incorporated aspect, vegetation type, soil depth, lithology, distance from the ocean, years since road treatment (for the road model) and years since harvest (for the forest model). The road model explained 48% of the variation in SOC in the upper 50 cm of mineral soils and the forest model, 54%

  19. The relative abundance of predicted genes associated with ammonia-oxidation, nitrate reduction, and biomass decomposition in mineral soil are altered by intensive timber harvest.

    Science.gov (United States)

    Mushinski, R. M.; Zhou, Y.; Gentry, T. J.; Boutton, T. W.

    2017-12-01

    Forest ecosystems in the southern United States are substantially altered by anthropogenic disturbances such as timber harvest and land conversion, with effects being observed in carbon and nutrient pools as well as biogeochemical processes. Furthermore, the desire to develop renewable energy sources in the form of biomass extraction from logging residues may result in alterations in soil community structure and function. While the impact of forest management on soil physicochemical properties of the region has been studied, its' long-term effect on soil bacterial community composition and metagenomic potential is relatively unknown, especially at deeper soil depths. This study investigates how intensive organic matter removal intensities associated with timber harvest influence decadal-scale alterations in bacterial community structure and functional potential in the upper 1-m of the soil profile, 18 years post-harvest in a Pinus taeda L. forest of eastern Texas. Amplicon sequencing of the 16S rRNA gene was used in conjunction with soil chemical analyses to evaluate treatment-induced differences in community composition and potential environmental drivers of associated change. Furthermore, functional potential was assessed by using amplicon data to make metagenomic predictions. Results indicate that increasing organic matter removal intensity leads to altered community composition and the relative abundance of dominant OTUs annotated to Burkholderia and Aciditerrimonas. The relative abundance of predicted genes associated with dissimilatory nitrate reduction and denitrification were highest in the most intensively harvested treatment while genes involved in nitrification were significantly lower in the most intensively harvested treatment. Furthermore, genes associated with glycosyltransferases were significantly reduced with increasing harvest intensity while polysaccharide lyases increased. These results imply that intensive organic matter removal may create

  20. Timber salvage economics

    Science.gov (United States)

    Jeffrey P. Prestemon; Thomas P. Holmes

    2008-01-01

    Timber salvage is commonly done following natural disturbances, to recover some value from damaged forests. Decision making about salvage, however, is affected by ownership objectives, the nature of the damage agent, site factors, and the strength of the local timber market. For profit-maximizing landowners, salvage decisions must balance the cost of harvesting...

  1. Forest owners' timber sales satisfaction

    International Nuclear Information System (INIS)

    Pammo, R.; Ripatti, P.

    2003-01-01

    The TTS Institute has carried out a study concerning forest owners' timber sales. The material was collected in 2002 via a mail inquiry that targeted forest owners who sold timber during the years 1997-1999 and 1999-2002. Three quarters of the forest owners sold timber to the same timber buying company during both periods of 1997-1999 and 1999-2002. The most important reasons for selling to the same buyer were that they purchased all timber assortments, reliability and good timber price. Mainly the same reasons also applied when changing the timber buying company. The most sensitive groups to changing timber buyer were 60-69 year old, entrepreneurs, men, and owners of forest holdings between 20-29 hectares, owners of inherited forests and joint forest ownerships. The forest owners assessed the timber buying company's operations and its staff on the basis of the last timber sale. The forest owners gave best values for the timber buyer's reliability, the purchase of all timber assortments and the timber buyers' reputation. The worst values were given for cross-cutting and response to complaints. No less than 95 percent of forest owners were prepared to recommend their timber trade partner to acquaintances, friends or other forest owners. Yet only half of the forest owners recognized that their last timber sale experience would not affect which company will be selected for the nest timber sale process

  2. PROFIT-PC: a program for estimating maximum net revenue from multiproduct harvests in Appalachian hardwoods

    Science.gov (United States)

    Chris B. LeDoux; John E. Baumgras; R. Bryan Selbe

    1989-01-01

    PROFIT-PC is a menu driven, interactive PC (personal computer) program that estimates optimum product mix and maximum net harvesting revenue based on projected product yields and stump-to-mill timber harvesting costs. Required inputs include the number of trees/acre by species and 2 inches diameter at breast-height class, delivered product prices by species and product...

  3. Changes to timber market

    International Nuclear Information System (INIS)

    Haluza, I.

    2008-01-01

    Ten thousands of tree trunks have ended up in the Liptovska Mara lake. The fact that state owned company Lesy SR decided to store the timber in the reservoir as it could not sell it on the market represents a small revolution in the industry. About a year ago timber processing companies were fighting for timber and suddenly it cannot be sold and has to be stored in the reservoir waiting for better times. When the forestry and timber processing industry will not be in such a difficult situation as it is now. Timber, floor and furniture manufacturers claim that the demand for their products and consequently also prices are falling. Some have already started to decrease production and started making redundancies. And when manufacturers complain, the timber suppliers are not happy either. The reason is that the industry has been hit by several blows at the same time. In last three to four years forests in Slovakia, Czech Republic, Austria, Scandinavia and in Canada have suffered several heavy windstorms after which large volumes of timber had to be processed quickly. So there was an excess of timber, particularly spruce. This created an ideal situation for the processing industry where the more agile companies increased their market share and offered timber at more competitive prices. (authors)

  4. Timber resource statistics for southwest Washington.

    Science.gov (United States)

    Patricia M. Bassett; Daniel D. Oswald

    1981-01-01

    This report summarizes a 1978 timber-resource inventory of six counties in southwest Washington: Clark, Cowlitz, Lewis, Pacific, Skamania, and Wahkiakum. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  5. Timber resource statistics for eastern Washington.

    Science.gov (United States)

    Patricia M. Bassett; Daniel D. Oswald

    1983-01-01

    This report summarizes a 1980 timber resource inventory of the 16 forested counties in Washington east of the crest of the Cascade Range. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  6. Selection of Nepalese Timber for Small Wind Turbine Blade Construction

    DEFF Research Database (Denmark)

    Sinha, R.; Acharya, Parash; Freere, Peter

    2010-01-01

    , weathering effect on coatings, price, growth and availability of the timber. Mechanical properties such as Young's modulus of elasticity, breaking strength, breaking strain and Brinell's hardness of selected Nepalese timbers are presented. The effects of weathering on timbers without coating...

  7. Mapping resource use over a Russian landscape: an integrated look at harvesting of a non-timber forest product in central Kamchatka

    International Nuclear Information System (INIS)

    Hitztaler, Stephanie K; Bergen, Kathleen M

    2013-01-01

    Small-scale resource use became an important adaptive mechanism in remote logging communities in Russia at the onset of the post-Soviet period in 1991. We focused on harvesting of a non-timber forest product, lingonberry (Vaccinium vitis-idaea), in the forests of the Kamchatka Peninsula (Russian Far East). We employed an integrated geographical approach to make quantifiable connections between harvesting and the landscape, and to interpret these relationships in their broader contexts. Landsat TM images were used for a new classification; the resulting land-cover map was the basis for linking non-spatial data on harvesters’ gathering behaviors to spatial data within delineated lingonberry gathering sites. Several significant relationships emerged: (1) mature forests negatively affected harvesters’ initial choice to gather in a site, while young forests had a positive effect; (2) land-cover type was critical in determining how and why gathering occurred: post-disturbance young and maturing forests were significantly associated with higher gathering intensity and with the choice to market harvests; and (3) distance from gathering sites to villages and main roads also mattered: longer distances were significantly correlated to more time spent gathering and to increased marketing of harvests. We further considered our findings in light of the larger ecological and social dynamics at play in central Kamchatka. This unique study is an important starting point for conservation- and sustainable development-based work, and for additional research into the drivers of human–landscape interactions in the Russian Far East. (letter)

  8. Timber value—a matter of choice: a study of how end use assumptions affect timber values.

    Science.gov (United States)

    John H. Beuter

    1971-01-01

    The relationship between estimated timber values and actual timber prices is discussed. Timber values are related to how, where, and when the timber is used. An analysis demonstrates the relative values of a typical Douglas-fir stand under assumptions about timber use.

  9. Tree mortality from fires, bark beetles, and timber harvest during a hot and dry decade in the western United States (2003-2012)

    Science.gov (United States)

    Berner, Logan T.; Law, Beverly E.; Meddens, Arjan J. H.; Hicke, Jeffrey A.

    2017-06-01

    High temperatures and severe drought contributed to extensive tree mortality from fires and bark beetles during the 2000s in parts of the western continental United States. Several states in this region have greenhouse gas (GHG) emission targets and would benefit from information on the amount of carbon stored in tree biomass killed by disturbance. We quantified mean annual tree mortality from fires, bark beetles, and timber harvest from 2003-2012 for each state in this region. We estimated tree mortality from fires and beetles using tree aboveground carbon (AGC) stock and disturbance data sets derived largely from remote sensing. We quantified tree mortality from harvest using data from US Forest Service reports. In both cases, we used Monte Carlo analyses to track uncertainty associated with parameter error and temporal variability. Regional tree mortality from harvest, beetles, and fires (MORTH+B+F) together averaged 45.8 ± 16.0 Tg AGC yr-1 (±95% confidence interval), indicating a mortality rate of 1.10 ± 0.38% yr-1. Harvest accounted for the largest percentage of MORTH+B+F (˜50%), followed by beetles (˜32%), and fires (˜18%). Tree mortality from harvest was concentrated in Washington and Oregon, where harvest accounted for ˜80% of MORTH+B+F in each state. Tree mortality from beetles occurred widely at low levels across the region, yet beetles had pronounced impacts in Colorado and Montana, where they accounted for ˜80% of MORTH+B+F. Tree mortality from fires was highest in California, though fires accounted for the largest percentage of MORTH+B+F in Arizona and New Mexico (˜50%). Drought and human activities shaped regional variation in tree mortality, highlighting opportunities and challenges to managing GHG emissions from forests. Rising temperatures and greater risk of drought will likely increase tree mortality from fires and bark beetles during coming decades in this region. Thus, sustained monitoring and mapping of tree mortality is necessary to

  10. Impact of Imported Chinese Furniture on The Local Furniture Sector in Arusha City, Tanzania: Focusing on the Strategies of Furniture-Makers for Using Indigenous Timber Species

    OpenAIRE

    OGAWA, Sayaka

    2018-01-01

    The aim of this paper is to elucidate the strategies used by Tanzanian furnituremakers to deal with price competition from Chinese imported furniture by examining the changes in the local use of timber, which is becoming scarce due to destructive harvesting. Chinese furniture flowing into Tanzania is not only of a fashionable design but it is also cheap because it is constructed from low-quality timber and alternative materials. Small-scale Tanzanian furniture-makers operate their business ba...

  11. T-H-A-T-S: timber-harvesting-and-transport-simulator: with subroutines for Appalachian logging

    Science.gov (United States)

    A. Jeff Martin

    1975-01-01

    A computer program for simulating harvesting operations is presented. Written in FORTRAN IV, the program contains subroutines that were developed for Appalachian logging conditions. However, with appropriate modifications, the simulator would be applicable for most logging operations and locations. The details of model development and its methodology are presented,...

  12. Assessment of soil erosion sensitivity and post-timber-harvesting erosion response in a mountain environment of Central Italy

    Science.gov (United States)

    Borrelli, Pasquale; Schütt, Brigitta

    2014-01-01

    This study aimed to assess the effects of forest management on the occurrence of accelerated soil erosion by water. The study site is located in a mountainous area of the Italian Central Apennines. Here, forest harvesting is a widespread forestry activity and is mainly performed on the moderate to steep slopes of the highlands. Through modeling operations based on data on soil properties and direct monitoring of changes in the post-forest-harvesting soil surface level at the hillslope scale, we show that the observed site became prone to soil erosion after human intervention. Indeed, the measured mean soil erosion rate of 49 t ha- 1 yr- 1 for the harvested watershed is about 21 times higher than the rate measured in its neighboring undisturbed forested watershed (2.3 t ha- 1 yr- 1). The erosive response is greatly aggravated by exposing the just-harvested forest, with very limited herbaceous plant cover, to the aggressive attack of the heaviest annual rainfall without adopting any conservation practices. The erosivity of the storms during the first four months of field measurements was 1571 MJ mm h- 1 ha- 1 in total (i.e., from September to December 2008). At the end of the experiment (16 months), 18.8%, 26.1% and 55.1% of the erosion monitoring sites in the harvested watershed recorded variations equal or greater than 0-5, 5-10 and > 10 mm, respectively. This study also provides a quantification of Italian forestland surfaces with the same pedo-lithological characteristics exploited for wood supply. Within a period of ten years (2002-2011), about 9891 ha of coppice forest changes were identified and their potential soil erosion rates modeled.

  13. Harvesting of Non-timber Forest Products by the Local Communities in Mount Halimun-Salak National Park, West Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Yelin Adalina

    2014-09-01

    Full Text Available Local communities around the forest need to be involved in securing the sustainability of Mount Halimun Salak National Park (MHSNP, for example through the utilization of non-timber forest products (NTFPs such as flora in the utilization zone. This research was aimed to provide data and information about 3 kinds of vegetation producing resin (Pinus merkusii, Agathis dammara, and Hevea brasiliensis and the harvesting NTFPs by the community in the forest vicinity. The research was conducted in MHSNP, and data were analyzed through quantitative-descriptive. The survey method was employed in the study through interviews of respondents using structured questionnaires.   This study revealed that the vegetations at the stage of tree comprised of the following: (1 Agathis dammara (damar with Importance Value Index (IVI of 276.15% and density of 452 trees ha-1, (2 Pinus merkusii (pine trees with IVI of 300.0% and density of 552 trees ha-1, and (3 Hevea brasiliensis (rubber trees with IVI of 217.42%  and density of 85 trees ha-1. Pine, damar, and rubber sap tapping afforded contribution in 59.18, 4.41, and 60.71%, respectively of the total household incomes. Community involvement in the collection of NTFPs in national parks implicated to the increasing of the forest communities revenue and the forests will be maintained since public can get benefits from forest resources. Forest management should be directed as a producer of NTFPs that can increase the economic income of forest communities with attention to ecological factors. Keywords: Harvesting, non-wood forest products, Mount Halimun-Salak National Park, community around the  forests

  14. Optimal control of raw timber production processes

    Science.gov (United States)

    Ivan Kolenka

    1978-01-01

    This paper demonstrates the possibility of optimal planning and control of timber harvesting activ-ities with mathematical optimization models. The separate phases of timber harvesting are represented by coordinated models which can be used to select the optimal decision for the execution of any given phase. The models form a system whose components are connected and...

  15. Timber resource statistics for the Olympic Peninsula, Washington.

    Science.gov (United States)

    Patricia M. Bassett; Daniel D. Oswald

    1961-01-01

    This report summarizes a 1978-79 timber resource inventory of five counties in the Olympic Peninsula of Washington: Clallam, Grays Harbor, Jefferson, Mason, and Thurston. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  16. Harvesting of Non-timber Forest Products by the Local Communities in Mount Halimun-Salak National Park, West Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Yelin Adalina

    2014-08-01

    Full Text Available Local communities around the forest need to be involved in securing the sustainability of Mount Halimun Salak National Park (MHSNP, for example through the utilization of non-timber forest products (NTFPs such as flora in the utilization zone. This research was aimed to provide data and information about 3 kinds of vegetation producing resin (Pinus merkusii, Agathis dammara, and Hevea brasiliensis and the harvesting NTFPs by the community in the forest vicinity. The research was conducted in MHSNP, and data were analyzed through quantitative-descriptive. The survey method was employed in the study through interviews of respondents using structured questionnaires. This study revealed that the vegetations at the stage of tree comprised of the following: (1 Agathis dammara (damar with Importance Value Index (IVI of 276.15% and density of 452 trees ha-1, (2 Pinus merkusii (pine trees with IVI of 300.0% and density of 552 trees ha-1, and (3 Hevea brasiliensis (rubber trees with IVI of 217.42% and density of 85 trees ha-1. Pine, damar, and rubber sap tapping afforded contribution in 59.18, 4.41, and 60.71%, respectively of the total household incomes. Community involvement in the collection of NTFPs in national parks implicated to the increasing of the forest communities revenue and the forests will be maintained since public can get benefits from forest resources. Forest management should be directed as a producer of NTFPs that can increase the economic income of forest communities with attention to ecological factors.

  17. Operability and location of Wisconsin's timber resource.

    Science.gov (United States)

    Jerold T. Hahn; Mark H. Hansen

    1989-01-01

    Data collected during the 1983 Wisconsin Statewide forest inventory were used to examine operability of the timber resource based on seven operability components. Operability is the ease or difficulty of managing or harvesting timber because of physical conditions in the stand or on the site.

  18. Operability and location of Michigan's timber resource.

    Science.gov (United States)

    Mark H. Hansen; Jerold T. Hahn

    1987-01-01

    Operability is the ease or difficulty of managing or harvesting timber because of physical conditions in the stand or on the site. Data collected during the 1980 Michigan statewide forest inventory were used to examine operability of the timber resource based on seven operability components.

  19. Timber resource statistics for western Washington.

    Science.gov (United States)

    Coffin D. MacLean; Patricia M. Bassett; Glenn. Yeary

    1992-01-01

    This report summarizes a 1988-90 timber resource inventory of 19 counties in western Washington: Clallam, Clark, Cowlitz, Grays Harbor, Island, Jefferson, King, Kitsap, Lewis, Mason, Pacific, Pierce, San Juan, Skagit, Skamania, Snohomish, Thurston, Wahkiakum, and Whatcom. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  20. Recommendations for sustainable development of non-timber forest products

    Science.gov (United States)

    Gina H. Mohammed

    2001-01-01

    Non-timber forest products--or NTFPs--are considered here to be botanical products harvested or originating from forest-based species, but excluding primary timber products, industrial boards and composites, and paper products. A recent study of non-timber forest products in Ontario, Canada, identified at least 50 types of NTFPs and hundreds of specific products used...

  1. Aggregate Timber Supply: From the Forest to the Market

    Science.gov (United States)

    David N. Wear; Subhrendu K. Pattanayak

    2003-01-01

    Timber supply modeling is a means of formalizing the production behavior of heterogeneous landowners managing a wide variety of forest types and vintages within a region. The critical challenge of timber supply modeling is constructing theoretically valid and empirically practical aggregate descriptions of harvest behavior. Understanding timber supply is essential for...

  2. Spatial ecology of timber rattlesnakes on the hardwood ecosystem experiment: pre-treatment results

    Science.gov (United States)

    Brian J. MacGowan; Zachary J. Walker

    2013-01-01

    The timber rattlesnake (Crotalus horridus) is a species of conservation concern throughout much of its geographic range and may serve as a sentinel species in investigations of the effects of timber harvesting on forest reptiles. Our objective was to determine the effect of even-aged timber management regimes on timber rattlesnake home range and...

  3. Projected US timber and primary forest product market impacts of climate change mitigation through timber set-asides

    Science.gov (United States)

    Prakash Nepal; Peter J. Ince; Kenneth E. Skog; Sun J. Chang

    2013-01-01

    Whereas climate change mitigation involving payments to forest landowners for accumulating carbon on their land may increase carbon stored in forests, it will also affect timber supply and prices. This study estimated the effect on US timber and primary forest product markets of hypothetical timber set-aside scenarios where US forest landowners would be paid to forego...

  4. Timber Curtain

    DEFF Research Database (Denmark)

    2015-01-01

    Timber Curtain is a site specific architectural installation, which is part of a research project conducted at the Aarhus School of Architecture as collaboration between Ph.D. and associate professor Niels Martin Larsen and the author. Through a digitally scripted associative model we performed s...... of pinewood timber, machined with a CMS Antares 5-axis CNC router. The digital process generation and simulation was implemented with Rhinoceros 3D, Grasshopper and GHPython, and AlphaCAM was used for preparing the CNC-routing....

  5. Timber tracking

    DEFF Research Database (Denmark)

    Düdder, Boris; Ross, Omry

    2017-01-01

    Managing and verifying forest products in a value chain is often reliant on easily manipulated document or digital tracking methods - Chain of Custody Systems. We aim to create a new means of tracking timber by developing a tamper proof digital system based on Blockchain technology. Blockchain...

  6. Leakage Implications for European Timber Markets from Reducing Deforestation in Developing Countries

    Directory of Open Access Journals (Sweden)

    Mattias Boman

    2012-08-01

    Full Text Available Forest management strategies and policies such as REDD (reduced emissions from deforestation and forest degradation may have unintentional implications for forest sectors in countries not targeted by such policies. The success of a policy effort like REDD would result in a significant reduction in deforestation and forest degradation and an ensuing reduction in the supply of natural forest timber production within participating countries. This could in turn result in price increases, inducing a supply response outside project boundaries with possible implications for forest management as well as global carbon emissions. This paper reviews the literature to discern potential timber market implications for countries sourcing wood products from developing countries affected by REDD related conservation efforts. The literature reviewed shows varying degrees of market effects leakage—policy actions in one place creating incentives for third parties to increase timber harvesting elsewhere through the price mechanism—ranging from negligible to substantial. However, wood products in the studies reviewed are dealt with on quite an aggregated scale and are assumed to be more or less perfect substitutes for wood products outside conservation effort boundaries. The review suggests that a thorough mapping of the end-uses of tropical timber is needed to comprehensively analyze impacts on wood-product markets in regions such as Europe from conservation efforts in tropical developing countries. The types of tropical timber expected to be affected, in which applications they are used, which are the most likely substitutes and where they would be sourced, are issues that, along with empirical analysis of supply and demand price elasticities and degree of substitutability, should be investigated when assessing the overall effectiveness of REDD.

  7. Effect of timber harvesting on stormflow characteristics in headwater streams of managed, forested watersheds in the Upper Gulf Coastal Plain in Mississippi

    Science.gov (United States)

    Byoungkoo Choi; Jeff A. Hatten; Janet C. Dewey; Kyoichi Otsuki; Dusong Cha

    2013-01-01

    Headwater streams are crucial parts of overall watershed dynamics because they comprise more than 50–80% of stream networks and watershed land areas. This study addressed the influence of headwater areas (ephemeral and intermittent) on stormflow characteristics following harvest within three first–order catchments in the Upper Gulf Coastal Plain of Mississippi. Four...

  8. Price

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The price terms in wheeling contracts very substantially, reflecting the differing conditions affecting the parties contracting for the service. These terms differ in the manner in which rates are calculated, the formulas used, and the philosophy underlying the accord. For example, and EEI study found that firm wheeling rates ranged from 20 cents to $1.612 per kilowatt per month. Nonfirm rates ranged from .15 mills to 5.25 mills per kilowatt-hour. The focus in this chapter is on cost-based rates, reflecting the fact that the vast majority of existing contracts are based on rate designs reflecting embedded costs. This situation may change in the future, but, for now, this fact can't be ignored

  9. Timber Management Opportunities for Nebraska 1983-1992

    Science.gov (United States)

    W. Brad Smith; Tom D. Wardle

    1984-01-01

    Reviews opportunities for treatment of timber stands in Nebraska for the decade 1983 - 1992. Under the assumptions and management guides specified, 52 percent of Nebraska''s commercial forest land would benefit from timber harvest or some other form of treatment during the decade.

  10. Non-timber forest products and forest stewardship plans

    Science.gov (United States)

    Becky Barlow; Tanner Filyaw; Sarah W. Workman

    2015-01-01

    To many woodland owners “harvesting” typically means the removal of timber from forests. In recent years many landowners have become aware of the role non-timber forest products (NTFPs) can play in supplemental management strategies to produce income while preserving other forest qualities. NTFPs are a diverse group of craft, culinary, and medicinal products that have...

  11. Impacts on South Carolina timber production over the last five decades.

    Science.gov (United States)

    Jinglong Mo; Thomas Straka; Richard Harper

    2013-01-01

    Timberland ownership patterns and national forest timber harvesting policy have undergone significant changes in South Carolina over the past five decades. Timber output studies for the state commonly focused on short time frames and seldom addressed timberland ownership patterns in detail. We describe fifty-year timber output for South Carolina, allowing us to address...

  12. Using TPO data to estimate timber demand in support of planning on the Tongass National Forest

    Science.gov (United States)

    Jean M. Daniels; Michael D. Paruszkiewicz; Susan J. Alexander

    2015-01-01

    Projections of Alaska timber products output, the derived demand for logs, lumber, residues, and niche products, and timber harvest by owner are developed by using a trend-based analysis. This is the fifth such analysis performed since 1990 to assist planners in meeting statutory requirements for estimating planning cycle demand for timber from the Tongass National...

  13. Markets, Government Policy, and China’s Timber Supply

    Science.gov (United States)

    Han Zhang; Joseph Buongiorno

    2012-01-01

    China’s domestic demand and exports of wood products are rising rapidly compared to domestic supply. The determinants of timber supply in China were investigated with panel data from 25 provinces from 1999 to 2009. The results indicated that China’s timber supply had responded to both market forces, reflected by timber prices largely determined by world demand and...

  14. Non-timber forest products in Hawaii

    Science.gov (United States)

    Katie Kamelamela; James B. Friday; Tamara Ticktin; Ashley. Lehman

    2015-01-01

    Hawaiian forests provide a wide array of non-timber forest products for both traditional and modern uses. Flowers, vines, and ferns are collected for creating garlands or lei for hula dances and parades. Lei made from materials gathered in the forest are made for personal use and sold, especially during graduation times. Bamboo is harvested for structures and for...

  15. Implementing CITES regulations for timber.

    Science.gov (United States)

    Blundell, Arthur G

    2007-03-01

    Foresters are currently confronted with a new challenge. For the first time a commonly traded timber species has been listed on the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). At the 12th Conference of the Parties in November 2002, countries voted 68 to 30 to place the premier timber species of Latin America, big-leaf mahogany (Swietenia macrophylla King [Meliaceae]), on CITES Appendix II. Under Appendix II regulations, trade in mahogany requires that exporting countries verify that each shipment was legally obtained and that its harvest was non-detrimental to the survival of the species. Unfortunately, implementation has been weak, in part because countries have yet to develop a common, pragmatic, cost-effective system to make the legal and non-detriment findings. This paper recommends what such a system might include.

  16. Long term contracts signed in Slovak timber business

    International Nuclear Information System (INIS)

    Haluza, I.

    2005-01-01

    The Slovak timber business is changing. The state-owned company, SR Forests, which cuts more then 50% of Slovak timber has signed long term agreements with major domestic timber processing companies - Smrecina, the Rettenmeier Tatra Timber saw mill in Liptovsky Mikulas and two paper mills - Mondi SCP Ruzomberok and Kappa Sturovo. In the past, only quarterly contracts were signed. Now, for the first time, two-year contracts have been signed that should help the timber processing industry and the forestry sector. The General Director of Lesy SR (SR Forests), Karol Vins, hopes for better sale prices. Company headquarters wants to maintain better control of prices than under the old system of timber sales by its branches. In the opinion of the General Director of the Forestry Section at the Ministry of Agriculture, long term contracts will guarantee a stable delivery of timber to processing companies, giving investors in new production capacity a better position in negotiations with banks regarding financing. According to K. Vins, long term contracts have so far only been negotiated with major timber processing companies which are mostly controlled by foreign capital and therefore have good payment discipline. The Association of the Timber Processing Industry is unhappy regarding developments and Lesy SR has not invited domestic companies to these negotiations

  17. Damping in Timber Structures

    OpenAIRE

    Labonnote, Nathalie

    2012-01-01

    Key point to development of environmentally friendly timber structures, appropriate to urban ways of living, is the development of high-rise timber buildings. Comfort properties are nowadays one of the main limitations to tall timber buildings, and an enhanced knowledge on damping phenomena is therefore required, as well as improved prediction models for damping. The aim of this work has consequently been to estimate various damping quantities in timber structures. In particular, models h...

  18. Harvesting systems for the northern forest hardwoods

    Science.gov (United States)

    Chris B. LeDoux

    2011-01-01

    This monograph is a summary of research results and environmental compliance measures for timber harvesting operations. Data are presented from the Northern Research Station's forest inventory and analysis of 20 states in the northern forest hardwoods. Harvesting systems available in the region today are summarized. Equations for estimating harvesting costs are...

  19. North Dakota timber industry: an assessment of timber product output and use, 2009

    Science.gov (United States)

    David E. Haugen; Robert A. Harsel

    2013-01-01

    Presents recent North Dakota forest industry trends; production and receipts of industrial roundwood; and production of saw logs and other products in 2009. Logging residue generated from timber harvest operations is reported, as well as wood and bark residue generated at primary wood-using mills and disposition of mill residues.

  20. South Dakota timber industry: an assessment of timber product output and use, 2009

    Science.gov (United States)

    Ronald J. Piva; Gregory J. Josten

    2013-01-01

    Presents recent South Dakota forest industry trends; production and receipts of industrial roundwood; and production of saw logs, veneer logs, pulpwood, and other products in 2009. Logging residue generated from timber harvest operations is reported, as well as wood and bark residue generated at primary wood-using mills and disposition of mill residues.

  1. Avaliação das condições de segurança do trabalho na colheita e transporte florestal em propriedades rurais fomentadas no Estado do Espírito Santo Evaluation of work safety conditions of timber harvesting and transport in fomented farms of the state of Espírito Santo, Brazil

    Directory of Open Access Journals (Sweden)

    Juliana Lorensi do Canto

    2007-01-01

    Full Text Available Este trabalho foi desenvolvido com informações obtidas de 70 proprietários rurais fomentados, responsáveis por 90 contratos de fomento florestal, com o objetivo de caracterizar as condições de segurança do trabalho na colheita e transporte florestal, em propriedades rurais fomentadas no Estado do Espírito Santo. A área fomentada por contrato variava entre 1,5 e 100,0 ha, sendo de até 30 ha em 86,7% dos contratos e com relevo montanhoso em 61,2%. A colheita e transporte florestais foram terceirizados em 70 e 80% dos contratos amostrados, respectivamente, e realizados por conta dos proprietários nos demais. A maioria dos prestadores de serviço terceirizados era contratada informalmente. Foi empregada a mão-de-obra contratada na maioria dos contratos com colheita própria, sendo a maior parte não qualificada e contratada informalmente. Grande parte dos trabalhadores deslocava-se por conta própria até o local de colheita. Ocorreram acidentes de trabalho em 16,3% dos contratos, sendo 60% na colheita e transporte florestal próprios. A maioria dos acidentes aconteceu na atividade de corte e atingiu, principalmente, os membros inferiores e superiores do trabalhador acidentado. Os trabalhadores não utilizavam equipamentos de proteção individual em 62,1% dos contratos com colheita própria e em 23,0% dos terceirizados. Observou-se carência de material de primeiros socorros, bem como falta de instrução para o socorro de trabalhadores acidentados na colheita florestal.This research was developed with data obtained from 70 fomented farm owners in the State of Espírito Santo, Brazil, who were responsible for 90 forest contracts distributed in 22 cities of the State. The area fomented per contract ranged from 1.5 to 100 hectares, being 84.8% of contracts up to 30 ha and 59.8% with mountainous relief. Timber harvesting and log transport were outsourced and carried out by a subcontractor in 70% and 80% of the contracts respectively

  2. Section of mechanized timbering

    Energy Technology Data Exchange (ETDEWEB)

    Balaganskiy, S Ye; Aksanov, Sh I; Ardashev, K A; Mednik, L Ye; Mikhaylov, P G

    1980-09-05

    A section of mechanized timbering is claimed which contains a base, roof timber, hydraulic stand, hydraulic packing cylinders, packing telescopic shield hinged to the roof timber by means of guides. To improve the reliability of forming the filling massif, the packing telescopic shield is made in the form of individual telescopic beams with guards which are interconnected by means of cross beams, while the gaps between the telescopic beams are covered with elasic plates.

  3. timber for structural use

    African Journals Online (AJOL)

    HOD

    Logs of Apa timber were air-dried and along the stem, 324 pieces of test specimens were ..... (machine) manual with the load rate of 1mm/min ..... [16] Desch, H. E., Timber properties, 6th. Edition,. Revised by J. M. Dinwoodie. Macmillan ...

  4. Traditional timber frames

    NARCIS (Netherlands)

    Jorissen, A.J.M.; Hamer, den J.; Leijten, A.J.M.; Salenikovich, A.

    2014-01-01

    Due to new possibilities traditional timber framing has become increasingly popular since the beginning of the 21e century. Although traditional timber framing has been used for centuries, the expected mechanical behaviour is not dealt with in great detail in building codes, guidelines or text

  5. The Economics of Timber Supply: An Analytical Synthesis of Modeling Approaches

    Science.gov (United States)

    David N. Wear; Peter J. Parks

    1994-01-01

    The joint supply of timber and other services from forest environments plays a central role in most forest land debates. This paper defines a general conceptual model of timber supply that provides the context for discussing both individual harvest choice and aggregate supply models. While the structure and breadth of these models has developed considerably over the...

  6. Concurring Regulation in European Forest Law; Forest Certification and the New EU Timber Regulation

    NARCIS (Netherlands)

    Kistenkas, F.H.

    2013-01-01

    Newly made EU Timber Regulation (EUTR) may prima facie look like competing regulation and an overlap of the existing forest certification schemes of FSC and PEFC as also EUTR combats illegally harvested timber. The novel EUTR, however, is a public law scheme wheras FSC and PEFC are private law

  7. Timber resource statistics for non-Federal forest land in west-central Oregon.

    Science.gov (United States)

    Donald R. Gedney; Patricia M. Bassett; Mary A. Mei

    1987-01-01

    This report summarizes a 1985-86 timber resource inventory of the non-Federal forest land in the four counties (Benton, Lane, Lincoln, and Linn) in west-central Oregon. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  8. Timber resource statistics for non-federal forest land in northwest Oregon.

    Science.gov (United States)

    Donald R. Gedney; Patricia M. Bassett; Mary A. Mei

    1986-01-01

    This report summarizes a 1986 timber resource inventory of the non-Federal forest land in the 10 counties (Clackamas, Clatsop, Columbia, Hood River, Marion, Multnomah , Polk, Tillamook, Washington, and Yamhill) in northwest Oregon. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

  9. Assessing the spatial implications of interactions among strategic forest management options using a Windows-based harvest simulator.

    Science.gov (United States)

    Eric J. Gustafson; Luke V. Rasmussen

    2002-01-01

    Forest management planners must develop strategies to produce timber in ways that do not compromise ecological integrity or sustainability. These strategies often involve modifications to the spatial and temporal scheduling of harvest activities, and these strategies may interact in unexpected ways. We used a timber harvest simulator (HARVEST 6.0) to determine the...

  10. Timber Products Supply and Demand

    Science.gov (United States)

    Jeffrey P. Prestemon; Robert C. Abt

    2002-01-01

    This chapter describes historical, current, and projected timber inventories and timber product outputs from southern forests. It also attempts to place these quantities in national and international perspectives. Timber is the most valuable commercial commodity taken from most forests, and its removal strongly influences the character of those forests. Timber is...

  11. Procurement of timber for the Finnish forest industries

    International Nuclear Information System (INIS)

    Hakkila, P.

    1995-01-01

    The procurement of timber to the forest industries in the Nordic countries is based on the log-length or shortwood system, and employs load-carrying forwarders and chainsaw of single-grip harvesters. This technology is characterized by high productivity, safety, suitability for small-sized trees, high recovery of timber, and environmental friendliness. About one fourth of the industrial timber in the whole world is harvested using the log-length system. The challenge of ecological sustainability, multiple use of forests, adoption of thinnings as a tool of management, trend toward improved utilization of forest biomass, and shift from natural forests to plantations all increase the global interest in the log-length system. The paper presents a review of the Finnish forest sector, the technology of timber harvesting and transport, productivity of logging work, and costs of timber at the mill. The highly mechanized logging systems of the forest industries and the lighter technology of self-employed forest owners are discussed separately. Furthermore, the use of residual biomass as a source of clean and renewable energy, the Finnish logging machine industry, and forest operations research in Finland are also reviewed. (46 refs., 35 figs., 8 tabs.)

  12. Timber in Bridge Structures

    OpenAIRE

    Detkin, Viktoria

    2016-01-01

    The purpose of this final year project was to study the properties of timber as a structural material and the suitability of wood in load bearing members for bridge structures. For a case study, an existing timber bridge was selected. Due to its condition the bridge should be replaced. The design of a new bridge with steel beams holding a glulam deck was made. During the case study the replacement of steel beams by glulam timber ones was discussed. Some calculations were made in order to ...

  13. Who, what, and why: the products, their use, and issues about management of non-timber forest products in the United States

    Science.gov (United States)

    Susan J. Alexander

    2001-01-01

    Non-timber forest products in the United States include floral greens, Christmas ornamentals, wild edibles, medicinals, crafts, and transplants. Non-timber forest products are important to many people for many reasons. People harvest products from forests for personal use, cultural practices, and sale. The tremendous variety of species harvested for the many markets...

  14. State forest timber sales in 2006

    International Nuclear Information System (INIS)

    Office National des Forets

    2007-01-01

    For the first time since the 1999 storms, forest owners have experienced a favourable market. The combination of buoyant demand for both industrial round-wood and timber and consolidation of supply led to a significant increase in prices. With a logging volume of 15 million m 3 (standing timber equivalent), state forest timber supply has remained at a high level, slightly above that of 1999. The improved business cycle situation has pushed prices up, including for beech for which rates had stagnated for some time. However, in spite of the 15% rise compared to 2005, the average per cubic metre price sold by the ONF (31.20 euros), all categories of timber and all state forests taken together, remains well below the average for the 1996-1999 period (37.80 euros). While unsold stocks have fallen considerably, the ONF has sought to facilitate access to products by industry by modernising its sales methods in line with the new 2005 legislative and regulatory provisions. Greater flexibility in the rules applicable to privately negotiated spot sales and supply contracts should over time contribute to stabilizing and reducing the accessory costs of supply. The changes implemented over the last decade in favour of private sales, which now account for nearly 40% of volumes sold, should continue in the future. Of those volumes, 20% were sold under supply contracts, a proportion that is rising sharply. These contracts covered more than one million m 3 in 2006, encouraging the ONF to adopt a new sales scheme and establish structures for consultations with both forest municipalities and the downstream component of the industry. (authors)

  15. Emissions from prescribed burning of timber slash piles in Oregon.

    Science.gov (United States)

    Emissions from burning piles of post-harvest timber slash (Douglas fir) in Grande Ronde, Oregon were sampled using an instrument platform lofted into the plume using a tether-controlled aerostat or balloon. Emissions of carbon monoxide, carbon dioxide, methane, particulate matte...

  16. Tradeoffs between Three Forest Ecosystem Services across the State of New Hampshire, USA: Timber, Carbon, and Albedo

    Science.gov (United States)

    Lutz, D. A.; Burakowski, E. A.; Murphy, M. B.; Borsuk, M. E.; Niemiec, R. M.; Howarth, R. B.

    2014-12-01

    Albedo is an important physical property of the land surface which influences the total amount of incoming solar radiation that is reflected back into space. It is a critical ecosystem service that helps regulate the Earth's energy balance and, in the context of climate mitigation, has been shown to have a strong influence on the overall effectiveness of land management schemes designed to counteract climate change. Previously, we demonstrated that incorporating the physical effects of albedo into an ecological economic forest model of locations in the White Mountain National Forest, in New Hampshire, USA, leads to a substantially shorter optimal rotation period for forest harvest than under a carbon- and timber-only approach. In this study, we investigate similar tradeoffs at 565 sites across the entire state of New Hampshire in a variety of different forest types, latitudes, and elevations. Additionally, we use a regression tree approach to calculate the influence of biogeochemical and physical factors on the optimal rotation period. Our results suggest that in many instances, incorporating albedo may lead to optimal rotation times approaching zero, or, perpetual clear-cut. Overall, the difference between growing season and winter-time albedo for forested and harvested states was the most significant variable influencing the rotation period, followed by timber stumpage price, and biomass growth rate. These results provide an initial understanding of tradeoffs amongst these three ecosystem services and provide guidance for forest managers as to the relative important properties of their forests when these three services are incentivized economically.

  17. Linking state-and-transition simulation and timber supply models for forest biomass production scenarios

    Directory of Open Access Journals (Sweden)

    Jennifer K. Costanza

    2015-03-01

    Full Text Available We linked state-and-transition simulation models (STSMs with an economics-based timber supply model to examine landscape dynamics in North Carolina through 2050 for three scenarios of forest biomass production. Forest biomass could be an important source of renewable energy in the future, but there is currently much uncertainty about how biomass production would impact landscapes. In the southeastern US, if forests become important sources of biomass for bioenergy, we expect increased land-use change and forest management. STSMs are ideal for simulating these landscape changes, but the amounts of change will depend on drivers such as timber prices and demand for forest land, which are best captured with forest economic models. We first developed state-and-transition model pathways in the ST-Sim software platform for 49 vegetation and land-use types that incorporated each expected type of landscape change. Next, for the three biomass production scenarios, the SubRegional Timber Supply Model (SRTS was used to determine the annual areas of thinning and harvest in five broad forest types, as well as annual areas converted among those forest types, agricultural, and urban lands. The SRTS output was used to define area targets for STSMs in ST-Sim under two scenarios of biomass production and one baseline, business-as-usual scenario. We show that ST-Sim output matched SRTS targets in most cases. Landscape dynamics results indicate that, compared with the baseline scenario, forest biomass production leads to more forest and, specifically, more intensively managed forest on the landscape by 2050. Thus, the STSMs, informed by forest economics models, provide important information about potential landscape effects of bioenergy production.

  18. Linking state-and-transition simulation and timber supply models for forest biomass production scenarios

    Science.gov (United States)

    Costanza, Jennifer; Abt, Robert C.; McKerrow, Alexa; Collazo, Jaime

    2015-01-01

    We linked state-and-transition simulation models (STSMs) with an economics-based timber supply model to examine landscape dynamics in North Carolina through 2050 for three scenarios of forest biomass production. Forest biomass could be an important source of renewable energy in the future, but there is currently much uncertainty about how biomass production would impact landscapes. In the southeastern US, if forests become important sources of biomass for bioenergy, we expect increased land-use change and forest management. STSMs are ideal for simulating these landscape changes, but the amounts of change will depend on drivers such as timber prices and demand for forest land, which are best captured with forest economic models. We first developed state-and-transition model pathways in the ST-Sim software platform for 49 vegetation and land-use types that incorporated each expected type of landscape change. Next, for the three biomass production scenarios, the SubRegional Timber Supply Model (SRTS) was used to determine the annual areas of thinning and harvest in five broad forest types, as well as annual areas converted among those forest types, agricultural, and urban lands. The SRTS output was used to define area targets for STSMs in ST-Sim under two scenarios of biomass production and one baseline, business-as-usual scenario. We show that ST-Sim output matched SRTS targets in most cases. Landscape dynamics results indicate that, compared with the baseline scenario, forest biomass production leads to more forest and, specifically, more intensively managed forest on the landscape by 2050. Thus, the STSMs, informed by forest economics models, provide important information about potential landscape effects of bioenergy production.

  19. Harvesting systems and costs for southern pine in the 1980s

    Science.gov (United States)

    Frederick W. Cubbage; James E. Granskog

    1981-01-01

    Timber harvesting systems and their costs are a major concern for the forest products industries. In this paper, harvest costs per cord are estimated, using computer simulation, for current southern pine harvesting systems. The estimations represent a range of mechanization levels. The sensitivity of systems to factors affecting harvest costs - machine costs, fuel...

  20. A Computer Program to Evaluate Timber Production Investments Under Uncertainty

    Science.gov (United States)

    Dennis L. Schweitzer

    1968-01-01

    A computer program has been written in Fortran IV to calculate probability distributions of present worths of investments in timber production. Inputs can include both point and probabilistic estimates of future costs, prices, and yields. Distributions of rates of return can also be constructed.

  1. Timber resources of southwest Oregon.

    Science.gov (United States)

    Patricia M. Bassett

    1979-01-01

    This report presents statistics from a 1973 inventory of timber resources of Douglas County and from a 1974 inventory of timber resources of Coos, Curry, Jackson, and Josephine Counties, Oregon. Tables presented are of forest area and of timber volume, growth, and mortality.

  2. Connecting non-timber forest products stakeholders to information and knowledge: A case study of an Internet web site

    Science.gov (United States)

    James Chamberlain; Matt Winn; A.L. Hammett

    2009-01-01

    Many products are harvested from forests that are not timber-based but are based on plant materials. These non-timber forest products (NTFPs) have not been fully incorporated into economic development programs, yet they provide significant monetary benefits for rural entrepreneurs. Interest in NTFPs as alternative forest enterprises and sources of additional income has...

  3. New methods for estimating non-timber forest product output: an Appalachian case study

    Science.gov (United States)

    Steve Kruger; James. Chamberlain

    2015-01-01

    Assessing the size and structure of non-timber forest product (NTFP) markets is difficult due to a lack of knowledge about NTFP supply chains. Harvesting ginseng and other wild medicinal plants has long provided a source of income and cultural identity in Appalachian communities in the eastern United States. With the exception of ginseng, the extent of the harvest of...

  4. Timber frame walls

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Brandt, Erik

    2010-01-01

    A ventilated cavity is usually considered good practice for removing moisture behind the cladding of timber framed walls. Timber frame walls with no cavity are a logical alternative as they are slimmer and less expensive to produce and besides the risk of a two-sided fire behind the cladding....... It was found that the specific damages made to the vapour barrier as part of the test did not have any provable effect on the moisture content. In general elements with an intact vapour barrier did not show a critical moisture content at the wind barrier after four years of exposure....

  5. Design of timber groynes

    NARCIS (Netherlands)

    Perdok, U.; Crossman, M.; Verhagen, H.J.; Howard, S.; Simm, J.

    2003-01-01

    The performance and durability of timber groynes (or 'groins') is highly dependent on the design and detailing of the structure. Using knowledge and experience developed over generations an effective functional design can be achieved, which may ultimately result in lower whole life costs and provide

  6. Industrialized timber structures.

    Science.gov (United States)

    1974-01-01

    It was recently learned that a number of innovations in structural timber components are available to the construction industry, but that they were largely unknown to bridge designers. The purpose of this study was to develop for the Department a fea...

  7. Growing Timber Structures

    DEFF Research Database (Denmark)

    Tamke, Martin; Evers, Henrik Leander; Stasiuk, David

    2013-01-01

    The contemporary design of timber structures has to answer questions concerning structural stability, production impact and energy implications in ever earlier stages. The interrelation of these levels creates a complexity that is difficult to resolve through contemporary linear parametric...... to integrate the behaviour of networked systems into structures made from wooden material....

  8. Modeling the Influence of Dynamic Zoning of Forest Harvesting on Ecological Succession in a Northern Hardwoods Landscape

    Science.gov (United States)

    Patrick A. Zollner; Eric J. Gustafson; Hong S. He; Volker C. Radeloff; David J. Mladenoff

    2005-01-01

    Dynamic zoning (systematic alteration in the spatial and temporal allocation of even-aged forest management practices) has been proposed as a means to change the spatial pattern of timber harvest across a landscape to maximize forest interior habitat while holding timber harvest levels constant. Simulation studies have established that dynamic zoning strategies...

  9. The 1993 RPA timber assessment update

    Science.gov (United States)

    Richard W. Haynes; Darius M. Adams; John R. Mills

    1995-01-01

    This update reports changes in the Nation's timber resource since the 1989 RPA timber assessment. The timber resource situation is analyzed to provide projections for future cost and availability of timber products to meet demands. Prospective trends in demands for and supplies of timber, and the factors that affect these trends are examined. These include changes...

  10. Global sustainable timber supply and demand

    Science.gov (United States)

    Peter J. Ince

    2010-01-01

    Industrial timber use has provided timber revenue that has helped make timber supply and demand more sustainable in the leading timber producing regions of the world. Sustainable development implies not consuming more resources today than we can replace tomorrow, but sustainable forest management implies more than merely a non-declining supply of timber. Forests as a...

  11. PRICE AND PRICING STRATEGIES

    OpenAIRE

    SUCIU Titus

    2013-01-01

    In individual companies, price is one significant factor in achieving marketing success. In many purchase situations, price can be of great importance to customers. Marketers must establish pricing strategies that are compatible with the rest of the marketing mix. Management should decide whether to charge the same price to all similar buyers of identical quantities of a product (a one-price strategy) or to set different prices (a flexible price strategy). Many organizations, especially retai...

  12. Timber resources of Ohio

    Science.gov (United States)

    Neal P. Kingsley; Carl E. Mayer

    1970-01-01

    Under the authority of the McSweeney-McNary Forest Research Act of May 22, 1928, and subsequent amendments, the Forest Service, U. S. Department of Agriculture, conducts a series of continuing forest surveys of all states to provide up-to-date information about the forest resources of the Nation. A resurvey of the timber resources of Ohio was made in 1966 and 1967 by...

  13. Historic timber roof structures

    OpenAIRE

    Magina, Miguel Jorge

    2013-01-01

    Dissertação para obtenção do Grau de Mestre em Engenharia Civil – Estruturas e Geotecnia This dissertation covers the study of historic timber roof structures in Transylvania area - Romania, the structures type, its elements and connection variety between them. Procedures to study a structure of this category are approached. It is also referred semi and non-destructive tests that can be done to better understand the present wood characteristics, and potential reparation or strengthening...

  14. Harvested wood products and REDD+: looking beyond the forest border

    Directory of Open Access Journals (Sweden)

    Tunggul Butarbutar

    2016-05-01

    Full Text Available Abstract Background The focus of REDD+ is sensu stricto on maintaining forest carbon stocks. We extend the scope of sustainable management of forest from forests to timber utilization, and study carbon offsets resulting from the utilization of harvested timber for bio energy or harvested wood products (HWPs. The emission budget of harvesting operations depends on the loss of standing biomass by timber extracted from the forest site and logging losses on the one side, and on the other on the wood end use and the utilization of processing residues. We develop two scenarios to quantify the magnitude of CO2 emissions by (1 energetic utilization, and (2 energetic and material utilization of harvested timber and compare the substitution effects for different fossil energy sources. Results The direct energetic use of harvested timber does not compensate for the losses of forest carbon stock. Logging residuals and displacement factors reflecting different wood use constitute by far the most important factor in potential emission reductions. Substitution effects resulting from energetic use of mill residuals and from HWPs have only a subordinated contribution to the total emissions as well as the type of fossil fuel utilized to quantify substitution effects. Material substitution effects associated with harvested wood products show a high potential to increase the climate change benefits. Conclusions The observation and perception of REDD+ should not be restricted to sustainable management and reduced impact logging practices in the forest domain but should be extended to the utilization of extracted timber. Substitution effects from material and energetic utilization of harvested timber result in considerable emission reductions, which can compensate for the loss of forest carbon, and eventually contribute to the overall climate change mitigation benefits from forestry sector.

  15. Prices and Price Setting

    NARCIS (Netherlands)

    R.P. Faber (Riemer)

    2010-01-01

    textabstractThis thesis studies price data and tries to unravel the underlying economic processes of why firms have chosen these prices. It focuses on three aspects of price setting. First, it studies whether the existence of a suggested price has a coordinating effect on the prices of firms.

  16. Curved Folded Plate Timber Structures

    OpenAIRE

    Buri, Hans Ulrich; Stotz, Ivo; Weinand, Yves

    2011-01-01

    This work investigates the development of a Curved Origami Prototype made with timber panels. In the last fifteen years the timber industry has developed new, large size, timber panels. Composition and dimensions of these panels and the possibility of milling them with Computer Numerical Controlled machines shows great potential for folded plate structures. To generate the form of these structures we were inspired by Origami, the Japanese art of paper folding. Common paper tessellations are c...

  17. Monitoring of timber structures: Editorial

    OpenAIRE

    Kurz, Jochen Horst

    2015-01-01

    Timber structures have been in use for centuries, with proven durability. In recent years, timber has become particularly important, due to its standing as a truly renewable material for construction and carbon storage purposes. The material behaviour of wood is known and understood. The current design concepts for timber structures are also well developed. Nevertheless, the underlying processes of the ageing and deterioration of wood are complex, and the anisotropic structure of wood require...

  18. Timber productivity research gaps for extensive forest management

    Science.gov (United States)

    L.C. Irland

    2011-01-01

    On extensive areas of small scale forests, significant opportunities for improving the value of future timber harvests while also improving other resource values are now being missed. A new focus on practical extensive management research is needed, especially as implementation of intensive practices has been declining in many areas, and new ‘‘close to nature’’...

  19. Timber management planning with timber ram and goal programming

    Science.gov (United States)

    Richard C. Field

    1978-01-01

    By using goal programming to enhance the linear programming of Timber RAM, multiple decision criteria were incorporated in the timber management planning of a National Forest in the southeastern United States. Combining linear and goal programming capitalizes on the advantages of the two techniques and produces operationally feasible solutions. This enhancement may...

  20. Timber floors strengthened with concrete

    NARCIS (Netherlands)

    Blass, H.J.; Linden, M.L.R. van der; Schlager, M.

    1998-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are not new (Pokulka, 1997) and form a simple and practical solution, they are not widely adopted. One of the reasons for this is the Jack of uniform design rules. In this research

  1. Timber designers' manual

    CERN Document Server

    Ozelton, E C

    2008-01-01

    This major reference manual covers both overall and detail design of structural timber, including aspects such as shear deflection, creep, dynamic and lateral stability considerations for flexural members.Available for the first time in paperback, the Third Edition was substantially revised to take account of the many changes since the previous edition was published in 1984. It is based on British Standard BS 5268-2: 2002, which brought design concepts closer to European practice and Eurocode 5.Features of the Third Edition include:* information on bolt values including

  2. Clearwood quality and softwood lumber prices: what's the real premium?

    Science.gov (United States)

    Thomas R. Waggener; Roger D. Fight

    1999-01-01

    Diminishing quantities of appearance grade lumber and rising price premiums for it have accompanied the transition from old-growth to young-growth timber. The price premiums for better grades are an incentive for producers to undertake investments to increase the yield of those higher valued products. Price premiums, however, are also an incentive for users to...

  3. Dynamics of Timber Market Integration in Sweden

    Directory of Open Access Journals (Sweden)

    Vishal Chandr Jaunky

    2015-12-01

    Full Text Available This paper addresses the performance of the timber markets (Scots pine, Pinus silvestris L. and Norway spruce, Picea abies (L. Karst. by evaluating the order of market integration in three Swedish regions (Central, Northern, and Southern. Quarterly data of delivery prices are employed over the period 1999Q1–2012Q4. Various unit root and cointegration tests have been computed. The results indicate that the variables are integrated of first order and co-integrated, especially after controlling for structural breaks. This supports the law-of-one-price hypothesis (LOP. However, the effects of structural shocks on forestry are arguably significant and these are controlled for while performing a vector error-correction mechanism (VECM-based Granger-causality test. Bi-directional causality between the Northern and central markets is uncovered in the short-run. In the long-run, a similar causal effect is detected between Northern and Southern markets while the central market emerges as the price leader. Further investigation is carried out using variance decompositions and impulse response functions and these approaches also tend to confirm the existence of a single market well, as price interdependence between markets.

  4. Probabilistic modeling of timber structures

    DEFF Research Database (Denmark)

    Köhler, Jochen; Sørensen, John Dalsgaard; Faber, Michael Havbro

    2007-01-01

    The present paper contains a proposal for the probabilistic modeling of timber material properties. It is produced in the context of the Probabilistic Model Code (PMC) of the Joint Committee on Structural Safety (JCSS) [Joint Committee of Structural Safety. Probabilistic Model Code, Internet...... Publication: www.jcss.ethz.ch; 2001] and of the COST action E24 ‘Reliability of Timber Structures' [COST Action E 24, Reliability of timber structures. Several meetings and Publications, Internet Publication: http://www.km.fgg.uni-lj.si/coste24/coste24.htm; 2005]. The present proposal is based on discussions...... and comments from participants of the COST E24 action and the members of the JCSS. The paper contains a description of the basic reference properties for timber strength parameters and ultimate limit state equations for timber components. The recommended probabilistic model for these basic properties...

  5. Market Definition For Hardwood Timber in the Southern Appalachians

    Science.gov (United States)

    Jeffrey P. Prestemon; John M. Pye; Karen Lee Abt; David N. Wear

    1999-01-01

    Direct estimation of aggregate hardwood supply is seriously complicated by the diversity of prices, species, and site conditions in hardwood stands. An alternative approach is to aggregate regional supply based on stumpage values of individual stands, arguably the real driver of harvest decisions. Complicating this approach is that species-specific prices are only...

  6. Sensitivity of TRIM projections to management, harvest, yield, and stocking adjustment assumptions.

    Science.gov (United States)

    Susan J. Alexander

    1991-01-01

    The Timber Resource Inventory Model (TRIM) was used to make several projections of forest industry timber supply for the Douglas-fir region. The sensitivity of these projections to assumptions about management and yields is discussed. A base run is compared to runs in which yields were altered, stocking adjustment was eliminated, harvest assumptions were changed, and...

  7. Balancing Conservation and Economic Sustainability: The Future of the Amazon Timber Industry

    Science.gov (United States)

    Merry, Frank; Soares-Filho, Britaldo; Nepstad, Daniel; Amacher, Gregory; Rodrigues, Hermann

    2009-09-01

    Logging has been a much maligned feature of frontier development in the Amazon. Most discussions ignore the fact that logging can be part of a renewable, environmentally benign, and broadly equitable economic activity in these remote places. We estimate there to be some 4.5 ± 1.35 billion m3 of commercial timber volume in the Brazilian Amazon today, of which 1.2 billion m3 is currently profitable to harvest, with a total potential stumpage value of 15.4 billion. A successful forest sector in the Brazilian Amazon will integrate timber harvesting on private lands and on unprotected and unsettled government lands with timber concessions on public lands. If a legal, productive, timber industry can be established outside of protected areas, it will deliver environmental benefits in synergy with those provided by the region’s network of protected areas, the latter of which we estimate to have an opportunity cost from lost timber revenues of 2.3 billion over 30 years. Indeed, on all land accessible to harvesting, the timber industry could produce an average of more than 16 million m3 per year over a 30-year harvest cycle—entirely outside of current protected areas—providing 4.8 billion in returns to landowners and generating 1.8 billion in sawnwood sales tax revenue. This level of harvest could be profitably complemented with an additional 10% from logging concessions on National Forests. This advance, however, should be realized only through widespread adoption of reduced impact logging techniques.

  8. The impact of ultraviolet radiation on timber

    International Nuclear Information System (INIS)

    Dawson, B.

    1993-01-01

    Photochemical degradation of timber, the outcome of exposure of timber to ultraviolet radiation, is a light induced chemical and physical decay. Timber is a collection of dead wood cells. Impacts of radiation on the growing tree are therefore outside the scope of this paper, which is primarily concerned with timber as a material. (author). 5 refs. 2 figs

  9. Probabilistic Modeling of Timber Structures

    DEFF Research Database (Denmark)

    Köhler, J.D.; Sørensen, John Dalsgaard; Faber, Michael Havbro

    2005-01-01

    The present paper contains a proposal for the probabilistic modeling of timber material properties. It is produced in the context of the Probabilistic Model Code (PMC) of the Joint Committee on Structural Safety (JCSS) and of the COST action E24 'Reliability of Timber Structures'. The present...... proposal is based on discussions and comments from participants of the COST E24 action and the members of the JCSS. The paper contains a description of the basic reference properties for timber strength parameters and ultimate limit state equations for components and connections. The recommended...

  10. Robustness Evaluation of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; čizmar, D.

    2010-01-01

    The present paper outlines results from working group 3 (WG3) in the EU COST Action E55 – ‘Modelling of the performance of timber structures’. The objectives of the project are related to the three main research activities: the identification and modelling of relevant load and environmental...... exposure scenarios, the improvement of knowledge concerning the behaviour of timber structural elements and the development of a generic framework for the assessment of the life-cycle vulnerability and robustness of timber structures....

  11. Temporal Decay in Timber Species Composition and Value in Amazonian Logging Concessions.

    Science.gov (United States)

    Richardson, Vanessa A; Peres, Carlos A

    2016-01-01

    Throughout human history, slow-renewal biological resource populations have been predictably overexploited, often to the point of economic extinction. We assess whether and how this has occurred with timber resources in the Brazilian Amazon. The asynchronous advance of industrial-scale logging frontiers has left regional-scale forest landscapes with varying histories of logging. Initial harvests in unlogged forests can be highly selective, targeting slow-growing, high-grade, shade-tolerant hardwood species, while later harvests tend to focus on fast-growing, light-wooded, long-lived pioneer trees. Brazil accounts for 85% of all native neotropical forest roundlog production, and the State of Pará for almost half of all timber production in Brazilian Amazonia, the largest old-growth tropical timber reserve controlled by any country. Yet the degree to which timber harvests beyond the first-cut can be financially profitable or demographically sustainable remains poorly understood. Here, we use data on legally planned logging of ~17.3 million cubic meters of timber across 314 species extracted from 824 authorized harvest areas in private and community-owned forests, 446 of which reported volumetric composition data by timber species. We document patterns of timber extraction by volume, species composition, and monetary value along aging eastern Amazonian logging frontiers, which are then explained on the basis of historical and environmental variables. Generalized linear models indicate that relatively recent logging operations farthest from heavy-traffic roads are the most selective, concentrating gross revenues on few high-value species. We find no evidence that the post-logging timber species composition and total value of forest stands recovers beyond the first-cut, suggesting that the commercially most valuable timber species become predictably rare or economically extinct in old logging frontiers. In avoiding even more destructive land-use patterns, managing

  12. Hinged roof timber

    Energy Technology Data Exchange (ETDEWEB)

    Shestov, P I; Golub, A G; Yefremov, V I

    1980-08-07

    A hinged roof timer is suggested which includes a beam with prong and loop on the end which have openings in the form of ring slits for the distance wedges and round for the pins. In this case the opening of the distance wedge in the ring is arranged in relation to the opening for the pin closer to the end of the beam, and in the prong, in the opposite order. In order to improve the operating quality by guaranteeing active support of the cantilever roof timber without increasing its overall dimensions for the height of the opening for the distance wedge in the prong and the ring, beams are arranged axisymmetrically to the longitudinal axis.

  13. Finite element analysis of composite concrete-timber beams

    Directory of Open Access Journals (Sweden)

    N. C. S. FORTI

    Full Text Available AbstractIn the search for sustainable construction, timber construction is gaining in popularity around the world. Sustainably harvested wood stores carbon dioxide, while reforestation absorbs yet more CO2. One technique involves the combination of a concrete slab and a timber beam, where the two materials are assembled by the use of flexible connectors. Composite structures provide reduced costs, environmental benefits, a better acoustic performance, when compared to timber structures, and maintain structural safety. Composite structures combine materials with different mechanical properties. Their mechanical performance depends on the efficiency of the connection, which is designed to transmit shear longitudinal forces between the two materials and to prevent vertical detachment. This study contributes with the implementation of a finite element formulation for stress and displacement determination of composite concrete-timber beams. The deduced stiffness matrix and load vector are presented along to numerical examples. Numerical examples are compared to the analytical equations available in Eurocode 5 and to experimental data found in the literature.

  14. Eleventh-century shift in timber procurement areas for the great houses of Chaco Canyon.

    Science.gov (United States)

    Guiterman, Christopher H; Swetnam, Thomas W; Dean, Jeffrey S

    2016-02-02

    An enduring mystery from the great houses of Chaco Canyon is the origin of more than 240,000 construction timbers. We evaluate probable timber procurement areas for seven great houses by applying tree-ring width-based sourcing to a set of 170 timbers. To our knowledge, this is the first use of tree rings to assess timber origins in the southwestern United States. We found that the Chuska and Zuni Mountains (>75 km distant) were the most likely sources, accounting for 70% of timbers. Most notably, procurement areas changed through time. Before 1020 Common Era (CE) nearly all timbers originated from the Zunis (a previously unrecognized source), but by 1060 CE the Chuskas eclipsed the Zuni area in total wood imports. This shift occurred at the onset of Chaco florescence in the 11th century, a time with substantial expansion of existing great houses and the addition of seven new great houses in the Chaco Core area. It also coincides with the proliferation of Chuskan stone tools and pottery in the archaeological record of Chaco Canyon, further underscoring the link between land use and occupation in the Chuska area and the peak of great house construction. Our findings, based on the most temporally specific and replicated evidence of Chacoan resource procurement obtained to date, corroborate the long-standing but recently challenged interpretation that large numbers of timbers were harvested and transported from distant mountain ranges to build the great houses at Chaco Canyon.

  15. Sustainability of Mangrove Harvesting: How do Harvesters' Perceptions Differ from Ecological Analysis?

    Directory of Open Access Journals (Sweden)

    Laura López-Hoffman

    2006-12-01

    Full Text Available To harvest biological resources sustainably, it is first necessary to understand what "sustainability" means in an ecological context, and what it means to the people who use the resources. As a case study, we examined the extractive logging of the mangrove Rhizophora mangle in the Río Limón area of Lake Maracaibo, in western Venezuela. The ecological definition of sustainable harvesting is harvesting that allows population numbers to be maintained or to increase over time. In interviews, the harvesters defined sustainable harvesting as levels permitting the maintenance of the mangrove population over two human generations, about 50 yr. In Río Limón, harvesters extract a combination of small adult and juvenile trees. Harvesting rates ranged from 7-35% of small adult trees. These harvesting levels would be sustainable according to the harvester's definition as long as juvenile harvesting was less than 40%. However, some harvesting levels that would be sustainable according to the harvesters were ecologically unsustainable, i.e., eventually causing declines in mangrove population numbers. It was also determined that the structure of mangrove forests was significantly affected by harvesting; even areas harvested at low, ecologically sustainable intensities had significantly fewer adult trees than undisturbed sites. Western Venezuela has no organized timber industry, so mangrove logs are used in many types of construction. A lagging economy and a lack of alternative construction materials make mangrove harvesting inevitable, and for local people, an economic necessity. This creates a trade-off between preserving the ecological characteristics of the mangrove population and responding to human needs. In order to resolve this situation, we recommended a limited and adaptive mangrove harvesting regime. We also suggest that harvesters could participate in community-based management programs as harvesting monitors.

  16. Grip for sawing round timber

    Energy Technology Data Exchange (ETDEWEB)

    1982-07-01

    This paper describes a device development at Gedling Colliery, Nottinghamshire Area, United Kingdom. It is a gripping attachment, designed to overcome the safety hazards involved in cross cutting timbers with a circular saw.

  17. FRP reinforcement of timber structures

    OpenAIRE

    Schober, Kay-Uwe; Harte, Annette M.; Kliger, Robert; Jockwer, Robert; Xu, Qingfeng; Chen, Jian-Fei

    2015-01-01

    Timber engineering has advanced over recent decades to offer an alternative to traditional materials and methods. The bonding of fibre reinforced plastics (FRP) with adhesives to timber structures for repair and strengthening has many advantages. However, the lack of established design rules has strongly restrained the use of FRP strengthening in many situations, where these could be a preferable option to most traditional techniques. A significant body of research has been carried out in rec...

  18. Forest growth and timber quality: crown models and simulation methods for sustainable forest management

    Science.gov (United States)

    Dennis P. Dykstra; Robert A. Monserud

    2009-01-01

    The purpose of the international conference from which these proceedings are drawn was to explore relationships between forest management activities and timber quality. Sessions were organized to explore models and simulation methodologies that contribute to an understanding of tree development over time and the ways that management and harvesting activities can...

  19. Non-timber forest products of the North-West District of Guyana

    NARCIS (Netherlands)

    Andel, T.R. van

    2000-01-01

    This thesis describes the use of non-timber forest products (NTFPs) by indigenous peoples of northwest Guyana. Part I contains a general analysis of NTFP harvesting in northwest Guyana Part II is an illustrated field guide of the useful plants encountered. Chapter 1: introduction Chapter

  20. characterisation and grading of two selected timber species grown

    African Journals Online (AJOL)

    HOD

    Structural timber is the timber used in framing and load bearing ... The main challenge in design with timber as structural member is to .... is the classification of timber based on particular ..... Azadirachta indica leaf extract on serum lipid profile.

  1. A cut above: building the market for fair trade timber

    Energy Technology Data Exchange (ETDEWEB)

    MacQueen, Duncan

    2008-02-15

    Unlike coffee and cotton, timber has yet to become a fair trade commodity. But now its time has come. Rights over forest resources are increasingly ceded to small-scale community forest enterprises (CFEs), as large-scale industrial logging is now largely discredited in the sustainable development context. The fair trade emphasis on just pricing for poorer producers is exactly what CFEs need as incentive to invest in sustainable forest management — and secure environmental and poverty reduction benefits at one stroke. With fair trade timber, CFEs could boost their entrepreneurial capacity using democratic business models with in-built social and environmental responsibility. The Fair Trade Labelling Organizations International and Forest Stewardship Council are exploring the ways and means through a new partnership, but more is needed. Consumers must be made aware of why paying higher prices is key to creating CFE incentives for sustainable forest management and poverty reduction. Time and money are needed for consumer education and installing fair trade timber in producer country forest policies, market segregation and procurement policies at all levels.

  2. Timber harvesting trends in the Lake States, 1983-1987.

    Science.gov (United States)

    W. Brad Smith; James E. Blyth

    1989-01-01

    Growing-stock removals for products have increased by 12% in the Lake States since 1983. Regional gains are led by red pine, aspen, and other hardwoods. New mills and technology promise to further improve markets for underutilized species throughout the region.

  3. Stream water responses to timber harvest: Riparian buffer width effectiveness

    Science.gov (United States)

    Barton D. Clinton

    2011-01-01

    Vegetated riparian buffers are critical for protecting aquatic and terrestrial processes and habitats in southern Appalachian ecosystems. In this case study, we examined the effect of riparian buffer width on stream water quality following upland forest management activities in four headwater catchments. Three riparian buffer widths were delineated prior to cutting; 0m...

  4. The value of volume and growth measurements in timber sales management of the National Forests

    Science.gov (United States)

    Lietzke, K. R.

    1977-01-01

    This paper summarizes work performed in the estimation of gross social value of timber volume and growth rate information used in making regional harvest decisions in the National Forest System. A model was developed to permit parametric analysis. The problem is formulated as one of finding optimal inventory holding patterns. Public timber management differs from other inventory holding problems in that the inventory, itself, generates value over time in providing recreational, aesthetic and environmental goods. 'Nontimber' demand estimates are inferred from past Forest Service harvest and sales levels. The solution requires a description of the harvest rates which maintain the optimum inventory level. Gross benefits of the Landsat systems are estimated by comparison with Forest Service information gathering models. Gross annual benefits are estimated to be $5.9 million for the MSS system and $7.2 million for the TM system.

  5. The timber resources of Rhode Island

    Science.gov (United States)

    Roland H. Ferguson; John R. McGuire; John R. McGuire

    1957-01-01

    This is a report on the first comprehensive survey ever made of the timber resources of Rhode Island. It shows, for the years 1952 and 1953, the area and condition of the forest land, the volume and quality of standing timber, the rates of timber growth and mortality, and the extent of timber cutting for forest products. The survey was made by the Forest Service as...

  6. Collapse Analysis of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2008-01-01

    of Structures and a probabilistic modelling of the timber material proposed in the Probabilistic Model Code (PMC) of the Joint Committee on Structural Safety (JCSS). Due to the framework in the Danish Code the timber structure has to be evaluated with respect to the following criteria where at least one shall...... to criteria a) and b) the timber frame structure has one column with a reliability index a bit lower than an assumed target level. By removal three columns one by one no significant extensive failure of the entire structure or significant parts of it are obtained. Therefore the structure can be considered......A probabilistic based collapse analysis has been performed for a glulam frame structure supporting the roof over the main court in a Norwegian sports centre. The robustness analysis is based on the framework for robustness analysis introduced in the Danish Code of Practice for the Safety...

  7. Mushrooms, trees, and money: value estimates of commercial mushrooms and timber in the pacific northwest.

    Science.gov (United States)

    Alexander, Susan J; Pilz, David; Weber, Nancy S; Brown, Ed; Rockwell, Victoria A

    2002-07-01

    Wild edible mushrooms are harvested in the forests of the Pacific Northwest, where both trees and mushrooms grow in the same landscape. Although there has been some discussion about the value of trees and mushrooms individually, little information exists about the joint production of, and value for, these two forest products. Through four case studies, the information needed to determine production and value for three wild mushroom species in different forests of the Pacific Northwest is described, and present values for several different forest management scenarios are presented. The values for timber and for mushrooms are site- and species-specific. On the Olympic Peninsula in Washington, timber is highly valued and chanterelles are a low-value product by weight; timber has a soil expectation value (SEV) 12 to 200 times higher than chanterelles. In south-central Oregon, timber and American matsutake mushrooms have the potential to have about the same SEV. In eastern Oregon, timber is worth 20 to 110 times as much as the morels that grow in the forest. Production economics is concerned with choices about how much and what to produce with what resources. The choices are influenced by changes in technical and economic circumstances. Through our description and analysis of the necessary definitions and assumptions to assess value in joint production of timber and wild mushrooms, we found that values are sensitive to assumptions about changes in forest management, yields for mushrooms and trees, and costs.

  8. The 2005 RPA timber assessment update.

    Science.gov (United States)

    Richard W. Haynes; Darius M. Adams; Ralph J. Alig; Peter J. Ince; John R. Mills; Xiaoping. Zhou

    2007-01-01

    This update reports changes in the Nation's timber resource since the Analysis of the Timber Situation in the United States was completed in 2003. Prospective trends in demands for and supplies of timber, and the factors that affect these trends are examined. These trends include changes in the U.S. economy, increased salvage of British Columbia beetle-killed...

  9. Control of borens in mine timbers

    Energy Technology Data Exchange (ETDEWEB)

    Yule, R A; Kennedy, M J

    1978-07-01

    The authors studied timber attack in Queensland mines by auger beetles and powder post beetles. When infested timber is taken into a mine the insects thrive at the temperatures (20 to 25 C) and relative humidities (70-90%) they encounter. Seven timber treatments were tested, and all were satisfactory except spraying with wood-preserving oil which contained a moderately effective insecticide.

  10. General notes on ductility in timber structures

    NARCIS (Netherlands)

    Jorissen, A.J.M.; Fragiacomo, M.

    2011-01-01

    The paper discusses the implications of ductility in design of timber structures under static and dynamic loading including earthquakes. Timber is a material inherently brittle in bending and in tension, unless reinforced adequately. However connections between timber members can exhibit significant

  11. Timber resource statistics for eastern Washington, 1995.

    Science.gov (United States)

    Neil McKay; Patricia M. Bassett; Colin D. MacLean

    1995-01-01

    This report summarizes a 1990-91 timber resource inventory of Washington east of the crest of the Cascade Range. The inventory was conducted on all private and public lands except National Forests. Timber resource statistics from National Forest inventories also are presented. Detailed tables provide estimates of forest area, timber volume, growth, mortality, and...

  12. Effects of variable retention harvesting on natural tree regeneration in Pinus resinosa (red pine) forests

    Science.gov (United States)

    Margaret W. Roberts; Anthony W. D' Amato; Christel C. Kern; Brian J. Palik

    2017-01-01

    Concerns over loss of ecosystem function and biodiversity in managed forests have led to the development of silvicultural approaches that meet ecological goals as well as sustain timber production. Variable Retention Harvest (VRH) practices, which maintain mature overstory trees across harvested areas, have been suggested as an approach to balance these objectives;...

  13. Cradle-to-gate life cycle impacts of redwood forest resource harvesting in northern California

    Science.gov (United States)

    Han-Sup Han; Elaine Oneil; Richard D. Bergman; Ivan L. Eastin; Leonard R. Johnson

    2015-01-01

    The first life cycle impact assessment for redwood (Sequoia sempervirens) forest management activities (i.e. a cradle-to-sawmill gate input) including the growing, harvesting, and hauling of redwood sawlogs to a sawmill was completed. In the stump-to-truck timber harvesting analysis, primary transport activities such as skidding and yarding consumed...

  14. Threshold responses of songbirds to long-term timber management on an active industrial forest

    Science.gov (United States)

    Becker, Douglas A.; Wood, Petra Bohall; Keyser, Patrick D.; Wigley, T. Bently; Dellinger, Rachel; Weakland, Cathy A.

    2011-01-01

    Forest managers often seek to balance economic benefits from timber harvesting with maintenance of habitat for wildlife, ecosystem function, and human uses. Most research on the relationship between avian abundance and active timber management has been short-term, lasting one to two years, creating the need to investigate long-term avian responses and to identify harvest thresholds when a small change in habitat results in a disproportionate response in relative abundance and nest success. Our objectives were to identify trends in relative abundance and nest success and to identify landscape-scale disturbance thresholds for avian species and habitat guilds in response to a variety of harvest treatments (clear-cuts, heavy and light partial harvests) over 14 years. We conducted point counts and monitored nests at an industrial forest in the central Appalachians of West Virginia during 1996–1998, 2001–2003, and 2007–2009. Early successional species increased in relative abundance across all three time periods, whereas interior-edge and forest-interior guilds peaked in relative abundance mid-study after which the forest-interior guild declined. Of 41 species with >10 detections, four (10%) declined significantly, 13 (32%) increased significantly (only three species among all periods), and 9 (22%) peaked in abundance mid-study (over the entire study period, four species had no significant change in abundance, four declined, and one increased). Based on piecewise linear models, forest-interior and interior-edge guilds’ relative abundance harvest thresholds were 28% total harvests (all harvests combined), 10% clear-cut harvests, and 18% light partial harvests, after which abundances declined. Harvest thresholds for the early successional guild were 42% total harvests, 11% clear-cut harvest, and 10% light partial harvests, and relative abundances increased after surpassing thresholds albeit at a reduced rate of increase after the clear-cut threshold. Threshold

  15. Evaluation of recycled timber members

    Science.gov (United States)

    Douglas R. Rammer

    1999-01-01

    An experimental study was conducted to evaluate the residual shear capacity of large Douglas-fir timbers used in a military facility in Ardeen Hills, MN. A S-point and 4-point bending test was used to determine the effects of checks and splits on the shear strength capacity. Experimental results are compared to past shear and flexural studies.

  16. Timber management opportunities in Pennsylvania

    Science.gov (United States)

    Henry H. Webster

    1960-01-01

    The Pennsylvania Department of Forests and Waters serves the people in managing state forest lands and in helping private owners manage their forest lands. To produce more timber from Pennsylvania forests, the Department applies many different forestry practices. But the more effort it spends in one direction, the less it can spend in others. So the Department must...

  17. Timber resource statistics for Oregon.

    Science.gov (United States)

    Sally Campbell; Paul Dunham; David. Azuma

    2004-01-01

    This report is a summary of timber resource statistics for all ownerships in Oregon. Data were collected as part of several statewide multiresource inventories, including those conducted by the Pacific Northwest Region (Region 6) on National Forest System lands in Oregon, by the Bureau of Land Management (BLM) on BLM lands in western Oregon, and by the Pacific...

  18. Understanding Loss Deductions for Timber

    Science.gov (United States)

    John Greene; Michael Jacobson

    1998-01-01

    Forestland owners whose timber has been destroyed may be eligible to take a deduction for the loss on their federal income tax. The loss must be physical in nature and caused by an identifiable event or combination of events that has run its course. There are two types of losses from natural events. Casualty losses are sudden, unexpected, and unusual - as from a fire...

  19. Timber Regulation and Value Chain in Community-Based Timber Enterprise and Smallholder Forestry in the Philippines

    Directory of Open Access Journals (Sweden)

    Juan M. Pulhin

    2016-07-01

    Full Text Available Forest tenure reform has no doubt attained significant gains in promoting social justice and equity in the forest sector, through legal recognition of the communities’ property rights over forest lands in many developing countries. This includes the right to harvest and market trees that the communities planted. Along these lines, the Philippines’ community-based forest management (CBFM and smallholder forestry have the potential to meet the country’s wood demand and contribute to its poverty alleviation goal. Realities on the ground, however, make this lofty aspiration seems too far-fetched. Formal and informal barriers along the timber value chain restrict the growth and obstruct opportunities for community-based timber enterprises (CBTEs and smallholder forestry. Using the case of CBFM and smallholder forestry in the Visayas and Mindanao Islands in the Philippines, respectively, this paper examines the hurdles posed by regulations and informal practices, such as restrictive policies and increased transaction costs, through a segment analysis of the timber value chain. It argues that failure to address these barriers would lead to the decline of CBTEs and smallholder enterprises, thus undermining the merits of the forest tenure reform.

  20. Using price data to consider risk in the evaluation of forest management investments.

    Science.gov (United States)

    David C. Baumgartner; Carol A. Hyldahl

    1991-01-01

    Shows how existing information on the historic prices of various timber species and products can be used to provide a measure of the market risk, return, and efficient portfolios of alternative forestry investments using examples from three Midwestern states.

  1. Managing timber to promote sustainable forests: a second-level course for the Sustainable Forestry Initiative of Pennsylvania

    Science.gov (United States)

    James C. Finley; Susan L. Stout; Timothy G. Pierson; Barbara J. McGuinness

    2007-01-01

    At least 80 percent of the raw material used for wood products by the forest industry is from privately owned woodlands. This publication provides material for a course designed to help landowners, foresters, and loggers work together to assess whether a planned timber harvest will retain the diversity of species on site. It includes methods for collecting overstory...

  2. System Reliability of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2010-01-01

    elements, alternate load path(s) etc. in the structural design. In general these characteristics can have a positive influence on system reliability of a structure however, in Eurocodes ductility is only awarded for concrete and steel structures but not for timber structures. It is well......-know that structural systems can redistribute internal forces due to ductility of a connection, i.e. some additional loads can be carried by the structure. The same effect is also possible for reinforced concrete structures and structures of steel. However, for timber structures codes do not award that ductility......For reduction of the risk of collapse in the event of loss of structural element(s), a structural engineer may take necessary steps to design a collapse-resistant structure that is insensitive to accidental circumstances e.g. by incorporating characteristics like redundancy, ties, ductility, key...

  3. Robustness Analyses of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Hald, Frederik

    2013-01-01

    The robustness of structural systems has obtained a renewed interest arising from a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures, many mo...... with respect to robustness of timber structures and will discuss the consequences of such robustness issues related to the future development of timber structures.......The robustness of structural systems has obtained a renewed interest arising from a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures, many...... modern building codes consider the need for the robustness of structures and provide strategies and methods to obtain robustness. Therefore, a structural engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper summaries issues...

  4. Forests, timber and rural livelihoods

    DEFF Research Database (Denmark)

    Hansen, Christian Pilegaard; Pouliot, Mariève; Marfo, Emmanuel

    2015-01-01

    Based on detailed income data of 478 rural households, the nexus between forest, trees and rural livelihoods in Ghana is investigated and applied to assess implications of the Voluntary Partnership Agreement (VPA) between the EU and Ghana on illegal logging. It is found that, after crops...... and benefits to trees on farm and fallow land to those occupying and cultivating the land. Such efforts would provide incentive for timber production and thus enhance rural livelihoods, while combatting illegal logging, deforestation and forest degradation....

  5. Integrating forest growth and harvesting cost models to improve forest management planning

    Science.gov (United States)

    J.E. Baumgras; C.B. LeDoux

    1991-01-01

    Two methods of estimating harvesting revenue--reported stumpage prices - and delivered prices minus estimated harvesting and haul costs were compared by estimating entry cash flows and rotation net present value for three simulated even-aged forest management options that included 1 to 3 thinnings over a 90 year rotation. Revenue estimates derived from stumpage prices...

  6. Prices versus Quantities

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn; Jensen, Frank

    illustrate that this result does not generalise to a search fishery, where marginal costs are allowed to depend on harvest. Hansen et al (2008) study a fishery where non-compliance with regulations is a problem. When the regulator is uncertain about non-compliance (compliance uncertainty), then landing fees......Weitzman (2002) studies the regulation of a fishery characterised by constant marginal harvest costs and shows that price regulation performs better than quantity regulation when the regulator is uncertain about the biological reproduction function (ecological uncertainty). Here, we initially...... are the preferred type of regulation, and Hansen et al (2008) find that this result does generalise to a search fishery where marginal costs depend on harvest. In this paper, we simulate a stochastic stock-recruitment model for the Danish cod fishery in the Kategat capturing both ecological and compliance...

  7. Managing Commercial Tree Species for Timber Production and Carbon Sequestration: Management Guidelines and Financial Returns

    Energy Technology Data Exchange (ETDEWEB)

    Gary D. Kronrad

    2006-09-19

    A carbon credit market is developing in the United States. Information is needed by buyers and sellers of carbon credits so that the market functions equitably and efficiently. Analyses have been conducted to determine the optimal forest management regime to employ for each of the major commercial tree species so that profitability of timber production only or the combination of timber production and carbon sequestration is maximized. Because the potential of a forest ecosystem to sequester carbon depends on the tree species, site quality and management regimes utilized, analyses have determined how to optimize carbon sequestration by determining how to optimally manage each species, given a range of site qualities, discount rates, prices of carbon credits and other economic variables. The effects of a carbon credit market on the method and profitability of forest management, the cost of sequestering carbon, the amount of carbon that can be sequestered, and the amount of timber products produced has been determined.

  8. The Timber Resource Inventory Model (TRIM): a projection model for timber supply and policy analysis.

    Science.gov (United States)

    P.L. Tedder; R.N. La Mont; J.C. Kincaid

    1987-01-01

    TRIM (Timber Resource Inventory Model) is a yield table projection system developed for timber supply projections and policy analysis. TRIM simulates timber growth, inventories, management and area changes, and removals over the projection period. Programs in the TRIM system, card-by-card descriptions of required inputs, table formats, and sample results are presented...

  9. Non-timber forest products of the North-West District of Guyana

    OpenAIRE

    Andel, T.R. van

    2000-01-01

    This thesis describes the use of non-timber forest products (NTFPs) by indigenous peoples of northwest Guyana. Part I contains a general analysis of NTFP harvesting in northwest Guyana Part II is an illustrated field guide of the useful plants encountered. Chapter 1: introduction Chapter 2: floristic composition and vegetation structure of well-drained mixed forest and 20- and 60-year old secondary forests. Previous forest inventories predicted a general low diversity for the North-West Distr...

  10. Price fairness

    OpenAIRE

    Diller, Hermann

    2013-01-01

    Purpose – The purpose of this article is to integrate the various strands of fair price research into a concise conceptual model. Design/methodology/approach – The proposed price fairness model is based on a review of the fair pricing literature, incorporating research reported in not only English but also German. Findings – The proposed fair price model depicts seven components of a fair price: distributive fairness, consistent behaviour, personal respect and regard for the partner, fair dea...

  11. Hogged wood fuel price analysis in the U.S. Pacific Northwest

    International Nuclear Information System (INIS)

    Biederman, R.T.; Blazek, C.F.; Fox, P.J.

    1991-01-01

    The purpose of this paper is to discuss the results of a comprehensive analysis of wood residues used for meeting energy requirements in the Pacific Northwest region of the United States. These wood residues are generated primarily from cutting, sawing, planning, sanding, and debarking activities in the lumber and plywood industries. While high-quality wood residues are commonly used as raw material in the manufacture of pulp and board commodities, a very large amount of wood residues are ultimately used for plant fuel purposes. The characteristics of this market for hogged wood fuel are examined in depth, with particular emphasis given to the factors which affect the supply, demand and price of hogged wood. Hogged wood has played an enormous role in the Pacific Northwest for over sixty years, a result of the massive regional timber harvest. Utilization of this renewable energy resource continues to be a large component in regional energy supply. Despite having a large number of highly integrated mills that both use and produce wood residues, the Pacific Northwest region experiences a lively trade in hogged wood. The IGT study discussed herein examines the determinants of the regional market price for hogged wood. A number of useful leading indicators are identified, and a statistical forecasting model is prepared to help predict future hogged wood prices. This model provides insight into the factors that are, and are not, important determinants of hogged wood price. The issue of fuel substitution is addressed in relation to the potential of hogged wood to displace some amount of primary energy sources such as natural gas and electricity. Also examined in the study are techniques to estimate the actual quantity of hogged wood available, and the quantity demanded by the marketplace. Conclusions presented in the study have important ramifications for understanding the price behavior and utilization of hogged wood fuel. 4 refs., 12 figs

  12. Wild harvest

    NARCIS (Netherlands)

    Cruz-Garcia, G.S.; Struik, P.C.; Johnson, D.E.

    2016-01-01

    <p>Rice fields provide not only a staple food but are also bio-diverse and multi-functional ecosystems. Wild food plants are important elements of biodiversity in rice fields and are critical components to the subsistence of poor farmers. The spatial and seasonal distribution of wild food plants

  13. Dynamic Pricing

    DEFF Research Database (Denmark)

    Sharifi, Reza; Anvari-Moghaddam, Amjad; Fathi, S. Hamid

    2017-01-01

    Dynamic pricing scheme, also known as real-time pricing (RTP), can be more efficient and technically beneficial than the other price-based schemes (such as flat-rate or time-of-use (TOU) pricing) for enabling demand response (DR) actions. Over the past few years, advantages of RTP-based schemes h...... of dynamic pricing can lead to increased willingness of consumers to participate in DR programs which in turn improve the operation of liberalized electricity markets.......Dynamic pricing scheme, also known as real-time pricing (RTP), can be more efficient and technically beneficial than the other price-based schemes (such as flat-rate or time-of-use (TOU) pricing) for enabling demand response (DR) actions. Over the past few years, advantages of RTP-based schemes...

  14. Timber resource of Missouri's Prairie, 1972.

    Science.gov (United States)

    Jerold T. Hahn; Alexander Vasilevsky

    1975-01-01

    The third timber inventory of Missouri's Prairie Forest Survey Unit shows substantial declines in both growing-stock and sawtimber volumes between 1959 and 1972. Commercial forest area declined by one-fifth. Presents highlights and statistics on forest area and timber volume, growth, mortality, ownership, and use in 1972.

  15. Tall timber building technologies in The Netherlands

    NARCIS (Netherlands)

    Jorissen, A.J.M.; Leijten, A.J.M.

    2008-01-01

    In the last few decades, structural timber for residential buildings has lost popularity because of problems related to floor vibrations, acoustics and fire resistance. In recent years, however, solutions to these problems have been developed and timber-framed housing is becoming increasingly

  16. Timber-concrete composite floor systems

    NARCIS (Netherlands)

    Linden, M.L.R. van der; Blass, H.J.

    1996-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are a simple and practical solution, they are not widely adopted. One of the reasons for this is the lack of uniform design mies. In this research programme shear tests on four different

  17. Aesthetic Qualities of Cross Laminated Timber

    DEFF Research Database (Denmark)

    Bejder, Anne Kirkegaard

    to its sustainable profile. In parallel to this, new production methods and further refined timber products have been developed. Among these are the engineered timber-based product Cross Laminated Timber (CLT) that show enhanced structural properties compared to unrefined timber. However, the question...... an undefined aesthetic potential that may innovate how we construct and perceive timber architecture, the overall aim of the thesis is to inquire into the architectural and aesthetic qualities of CLT. Through three chapters this thesis examines and discusses 1) the architectural qualities of CLT, 2......) the materiality of CLT, and 3) how one can deal with these qualitative aspects in the design process. This leads to: firstly, the development of an explicit model to help structuring the analysis and evaluation of the materiality of CLT, and secondly, a clarification and articulation of the aesthetic qualities...

  18. Nailed timber beams with I composed section

    Directory of Open Access Journals (Sweden)

    Jorge Luís Nunes de Góes

    2003-01-01

    Full Text Available The employment of built-up timber beams, made of commercial dimensions pieces, is becoming increasingly important in timber structures in Brazil, mainly due to the ever-growing scarcity of timber elements in larger sizes. The built-up system has vast application, from beams for residential buildings to girders for small bridges. The objective of this work is the theoretical and experimental study of nailed timber beams with composed cross section I. The design procedure of EUROCODE 5/93 and NBR 7190/97 are shown and evaluated, as well as the theory about the subject matter. The experimental evaluation of the theoretical models was made by means of bending tests in prototypes of built-up timber beams. The obtained results shows that the EUROCODE 5/93 procedure is the most indicated for evaluating effective bending stiffness, normal and shear stresses as well as the load on fasteners.

  19. Reliability Analysis of Structural Timber Systems

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Hoffmeyer, P.

    2000-01-01

    Structural systems like timber trussed rafters and roof elements made of timber can be expected to have some degree of redundancy and nonlinear/plastic behaviour when the loading consists of for example snow or imposed load. In this paper this system effect is modelled and the statistic...... of variation. In the paper a stochastic model is described for the strength of a single piece of timber taking into account the stochastic variation of the strength and stiffness with length. Also stochastic models for different types of loads are formulated. First, simple representative systems with different...... types of redundancy and non-linearity are considered. The statistical characteristics of the load bearing capacity are determined by reliability analysis. Next, more complex systems are considered modelling the mechanical behaviour of timber roof elements I stressed skin panels made of timber. Using...

  20. FOREST HARVEST SCHEDULING PLAN INTEGRATED TO THE ROAD NETWORK

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Belavenutti Martins da Silva

    2016-03-01

    Full Text Available In industrial forest plantations, the spatial distribution of management units for harvest scheduling influences the timber production cost and the non-renewable resources consumption, due to issues related to transport logistic. In this context, this research aimed to formulate Integer Linear Programming (ILP by means of the application of Floyd-Warshall network optimization algorithm to generate timber production routes, minimizing the production costs resulting from harvest activities and forest road maintenance. Then, scenarios were simulated considering different minimal harvest ages for Pinus spp. and Eucalyptus spp. stands. The planning horizon was five years with annual periodicity. The study area was 23,330 hectares of forests, located in Paraná state (southern Brazil. We compared the simulated scenarios according to the following parameter indicators: harvest income, building road network and the production unit cost. The decreasing of the minimal harvest age reduces the mean production of management units scheduled to be harvested, in other hand, it requires fewer roads to be built, and consequently increases the production unit cost. The solutions obtained by using ILP models presented an optimality gap lower than 0.1%.

  1. Tree-mendous Timber Evaluation

    Science.gov (United States)

    2004-01-01

    Funded and administered by NASA, the Affiliated Research Center (ARC) program transfers geospatial technologies from the Space Agency and participating universities to commercial companies, non-profit and trade organizations, and tribal governments. The origins of the ARC program date back to 1988, when NASA's Stennis Space Center initiated the Visiting Investigator Program to bring industry closer to spatial information technologies. The success of this trial program led to an expansion into the ARC program, whose goal is to enhance competitiveness of U.S. industries through more efficient use of remote sensing and related technologies. NASA's ARC program served as the foundation for the development of International Hardwood Resources, which then grew into Falcon Informatics with the acquisition of a technology from a European software company and a change of business models. Doylestown, Pennsylvania-based Falcon Informatics is now a world-leading information services company that combines in-depth timber industry experience with state-of-the-art software to serve the needs of national governments, international paper companies, and timber-investment management organizations.

  2. A review on environmental education in Myanmar Timber Enterprise

    International Nuclear Information System (INIS)

    Khin-Zaw

    2001-08-01

    Environmental education in the Myanmar Timber Enterprise (MTE) began formally in 1996. Environmental considerations had been incorporated in the deparmental instructions and operation manuals of extraction and wood processing since the emergence of MTE, then named STate Timber Board in 1948, but the modern concept of environmental conservation for sustainable development was introduced to the staff of MTE beginning only in 1996. The training contents constitute the defintion of environmental conservation as sustainable development, global environmental awareness, Myanmar's participation in global environmental undertakings, national institution and awareness progammes, the concept of reduced impact logging, code of harvesting, and above all, the environmental impact assessment (EIA) methodology as a tool for environmental management. In the MTE, 20 officers have been trained at a two-week workshop on EIA; 180 trainees from the Extraction Department, mostly the persons in charge of extraction ranges, have been trained at five-day short and mobile trainings on EIA around the country; and 948 officers and subordinate staff have been trained at the vocational training centres of MTE covering the above outline of the course, depending upon the training duration and trainees' rank, up to the end of December, 2000. Evaluation on EIA workshop and some training courses, problems and constraints encountered at the trainings and suggestions sought are also discussed in the paper. (author)

  3. Regional Markets for Non-timber Forest Products in Eastern Brazilian Amazon

    OpenAIRE

    Vuola, Matleena

    2013-01-01

    While export of non-timber forest products (NTFPs) has been promoted as a sustainable development strategy, the literature suggests that local and regional markets are also potentially important, not only for producers but also for traders and consumers (Shackleton et al. 2007). For producers, regional markets are thought to offer more accessible and more stable markets, while for traders, these markets offer employment, and for consumers, reasonably priced, diverse, fresh food. Consumptio...

  4. Transfer Pricing

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo

    2014-01-01

    Against a background of rather mixed evidence about transfer pricing practices in multinational enterprises (MNEs) and varying attitudes on the part of tax authorities, this paper explores how multiple aims in transfer pricing can be pursued across four different transfer pricing regimes. A MNE h...

  5. Gold prices

    OpenAIRE

    Joseph G. Haubrich

    1998-01-01

    The price of gold commands attention because it serves as an indicator of general price stability or inflation. But gold is also a commodity, used in jewelry and by industry, so demand and supply affect its pricing and need to be considered when gold is a factor in monetary policy decisions.

  6. 36 CFR 223.32 - Timber sale operating plan.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Timber sale operating plan... SALE AND DISPOSAL OF NATIONAL FOREST SYSTEM TIMBER Timber Sale Contracts Contract Conditions and Provisions § 223.32 Timber sale operating plan. Sale contracts with a term of 2 years or more shall provide...

  7. Inventory analysis of the timber industry in Ghana

    NARCIS (Netherlands)

    Eshun, J.F.; Potting, J.; Leemans, R.

    2010-01-01

    Background, aim, and scope The timber sector, i.e., forestry and timber industry, plays an important role in the socioeconomic development of Ghana through timber products export. Timber production in this sector is associated with increasing environmental burdens in terms of use of materials and

  8. Structural Reliability of the Nigerian Grown Abura Timber Bridge ...

    African Journals Online (AJOL)

    Structural reliability analysis was carried out on the Nigerian grown Abura timber, to ascertain its structural performance as timber bridge beams. Samples of the Nigerian grown Abura timber were bought from timber market, seasoned naturally and their structural/strength properties were determined at a moisture content of ...

  9. CONTEMPORARY SLOVENIAN TIMBER ARCHITECTURE INTERNATIONAL RECOGNIZED

    Directory of Open Access Journals (Sweden)

    Manja Kitek Kuzman

    2014-12-01

    Full Text Available The book presents Slovenia' s contemporary timber architecture. Thanks to its abundant forests, Slovenia has preserved the tradition of wood construction. As much as 60% of its surface is covered by forests. Slovenia is also the third most forested country in Europe. The high share of forest-covered surface allows for a sustainable production of high-quality wood. In the past, wood was used primarily in the construction of farm buildings, but now timber architecture is used for everything from residences and office buildings to public buildings such as community centres and schools. Timber construction is becoming increasingly popular. Apart from larger companies taking this approach, a great number of wooden houses have sprung up, built either on personal initiative or with the support of carpenter workshops. Slovenian timber architecture has taken a new approach to environmental and energy-efficiency problems and received great international recognition. The book discusses over fifty projects built over a ten-year period, and includes descriptions, photographs, and plans. The projects include residential areas, administration, and office, as well as tourist, educational, and industrial buildings. Timber architecture is presented as an integral part of the Slovenian landscape. The monograph will be useful to designers and future experts in their planning of optimal timber buildings and will highlight the main benefits of using timber construction.

  10. Harvesting pulpwood and firewood using a tractor-mounted single-grip harvester

    International Nuclear Information System (INIS)

    Ihonen, M.

    1998-01-01

    The TTS-Institute's Department of Forestry conducted a work study on the AM 240 felling-delimbing-cross-cutting -device. The timber was prepared into pulp- and fuelwood. The tops of the pulpwood stems and stems smaller than pulpwood were made into fuelwood. The base machine used was an agricultural tractor. The study is part of a research project titled Forest Owners' Energy-Wood Harvesting Technology. The combined productivity of preparing pulpwood and fuelwood varied between 2.8-4.1 m 3 per effective hour. Thus, the productivity achieved was of the same order as that reported in an earlier TTS-Institute study on the devices AM 200 model. The outturns on the sample strips included a fair amount of crooked hardwood timber, which iced to reduced productivity. During the work study the felling device functioned reliably. (author) 3 refs

  11. The Materiality of Novel Timber Architecture

    DEFF Research Database (Denmark)

    Bejder, Anne Kirkegaard; Kirkegaard, Poul Henning; Wraber, Ida Kristina

    2016-01-01

    In recent years, wood as a building material has gained renewed focus and, in parallel, new production methods and further refined timber products have been developed. Many of these novel timber building materials have gained significantly enhanced technical qualities, and the question is whether...... this is at the expense of wood’s sensuous and poetic qualities. The proposed method to deal with these questions is to develop a discursive model that can clarify aspects essential for analyzing and discussing the materiality of timber in its contemporary engineered forms. Firstly, this paper presents a theoretical...

  12. In-stand scenic beauty of variable retention harvests and mature forests in the U.S. Pacific Northwest: the effects of basal area, density, retention pattern and down wood

    Science.gov (United States)

    R.G. Ribe

    2009-01-01

    Tensions between amenity- and timber-based economies in the U.S. and Canadian Pacific Northwest motivated a study of scenic beauty inside mature forests and timber harvests. A diverse sample of regional forests, measures of forest structure, and large, representative samples of photographs and public judges were employed to measure scenic beauty inside unharvested...

  13. Reliability and Robustness Evaluation of Timber Structures

    DEFF Research Database (Denmark)

    Cizmar, Dean; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    In the last few decades there have been intensely research concerning reliability of timber structures. This is primarily because there is an increased focus on society on sustainability and environmental aspects. Modern timber as a building material is also being competitive compared to concrete...... and steel. However, reliability models applied to timber were always related to individual components but not the systems. as any real structure is a complex system, system behaviour must be of a particular interest. In the chapter 1 of this document an overview of stochastic models for strength and loads...... (deterministic, probabilistic and risk based approaches) of the robustness are given. Chapter 3 deals more detailed with the robustness of timber structures....

  14. Statistical Analysis of Data for Timber Strengths

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Hoffmeyer, P.

    Statistical analyses are performed for material strength parameters from approximately 6700 specimens of structural timber. Non-parametric statistical analyses and fits to the following distributions types have been investigated: Normal, Lognormal, 2 parameter Weibull and 3-parameter Weibull...

  15. Scale of harvesting by non-industrial private forest landowners

    Science.gov (United States)

    Melinda Vokoun; Gregory S. Amacher; David N. Wear

    2006-01-01

    We examine the intensity of harvesting decision by non-industrial landowners at the lowest price offer they deem acceptable, using a multiple bounded discrete choice stated preference approach that draws upon and connects two subfields of forestry, one identifying characteristics of landowners important to past harvesting or reforestation decisions, and another...

  16. Transfer Pricing

    DEFF Research Database (Denmark)

    Rohde, Carsten; Rossing, Christian Plesner

    trade internally as the units have to decide what prices should be paid for such inter-unit transfers. One important challenge is to uncover the consequences that different transfer prices have on the willingness in the organizational units to coordinate activities and trade internally. At the same time...... the determination of transfer price will affect the size of the profit or loss in the organizational units and thus have an impact on the evaluation of managers‟ performance. In some instances the determination of transfer prices may lead to a disagreement between coordination of the organizational units...

  17. Soil organic matter and nitrogen cycling in response to harvesting, mechanical site preparation, and fertilization in a wetland with a mineral substrate

    Science.gov (United States)

    James W. McLaughlin; Margaret R. Gale; Martin F. Jurgensen; Carl C. Trettin

    2000-01-01

    Forested wetlands are becoming an important timber resource in the Upper Great Lakes Region of the US. However, there is limited information on soil nutrient cycling responses to harvesting and post-harvest manipulations (site preparation and fertilization). The objective of this study was to examine cellulose decomposition, nitrogen mineralization, and soil solution...

  18. LEVERAGING RURAL LIVELIHOODS WITH FOREST CONSERVATION IN NIGERIA: THE ROLE OF NON-TIMBER FOREST PRODUCTS

    Directory of Open Access Journals (Sweden)

    Egbe BASSEY ETOWA

    2015-03-01

    Full Text Available In recent times some economists view Non-Timber Forest Products (NTFPs extraction and marketing as a better alternative to timber exploitation as a rural livelihood strategy. Harvesting and sale of NTFPs have the potential for accomplishing the dual goals of natural forest conservation and income generation for the rural inhabitants. Meanwhile, realization of these dual goals in Nigeria, require an understanding of how NTFPs functions in the face of marketing, ecological, geographic and institutional constraints. Following a conceptualization of NTFPs, this paper provides a vivid overview of the simultaneous roles of NTFPs in rural livelihood enhancement and forest conservation in Nigeria. It highlights governmental initiatives with respect to conservation, the challenges and prospects of NTFPs as a conservation strategy. Conclusively, the paper suggests that appropriate NTFPs development policies are required to simultaneously address forest depletion and poverty in rural areas of Nigeria.

  19. Management of young forest stands for integrated production of wood fuel and quality timber. Final report

    International Nuclear Information System (INIS)

    Lundmark, Tomas; Sahlen, Kenneth; Ulvcrona, Kristina

    2005-06-01

    The aim of this project has been to develop practical silvicultural measures that integrate the optimization of biomass production in dense young mixed stands with production of quality timber later during the rotation period. The results show that annual biomass production can be trippled by keeping young stands dense and adding fertilizers. At the same time by delaying the time for pre-commercial thinning (or replacing it with a biomass harvest) relative branch size in the lower part of the stem will be reduced. This support the hypothesis that biomass production can be improved if young stands are kept dense up to the height of 8-10 m and as a consequence of delayed thinning timber quality can also be improved. Important background data for technical development has also been provided as well as data needed for economical analyses of different silvicultural systems including the treatment of heterogenous dense stands with mixed species composition

  20. Optimizing wildlife habitat quality and oak regeneration in bottomland hardwoods using midstory control and partial harvests

    Science.gov (United States)

    Derek K. Alkire; Andrew W. Ezell; Andrew B. Self

    2011-01-01

    Bottomland hardwoods can provide both wildlife habitat and timber. However, past high-grading practices limit future income potential and have resulted in undesirable species composition in many areas. Thus, prevalence of desirable oak species should be increased. Our study will attempt to determine the proper harvest level for bottomland hardwoods which will optimize...

  1. Mapping wildfire and clearcut harvest disturbances in boreal forests with Landsat time series data

    Science.gov (United States)

    Todd Schroeder; Michael A. Wulder; Sean P. Healey; Gretchen G. Moisen

    2011-01-01

    Information regarding the extent, timing andmagnitude of forest disturbance are key inputs required for accurate estimation of the terrestrial carbon balance. Equally important for studying carbon dynamics is the ability to distinguish the cause or type of forest disturbance occurring on the landscape. Wildfire and timber harvesting are common disturbances occurring in...

  2. Accuracy in estimation of timber assortments and stem distribution - A comparison of airborne and terrestrial laser scanning techniques

    Science.gov (United States)

    Kankare, Ville; Vauhkonen, Jari; Tanhuanpää, Topi; Holopainen, Markus; Vastaranta, Mikko; Joensuu, Marianna; Krooks, Anssi; Hyyppä, Juha; Hyyppä, Hannu; Alho, Petteri; Viitala, Risto

    2014-11-01

    Detailed information about timber assortments and diameter distributions is required in forest management. Forest owners can make better decisions concerning the timing of timber sales and forest companies can utilize more detailed information to optimize their wood supply chain from forest to factory. The objective here was to compare the accuracies of high-density laser scanning techniques for the estimation of tree-level diameter distribution and timber assortments. We also introduce a method that utilizes a combination of airborne and terrestrial laser scanning in timber assortment estimation. The study was conducted in Evo, Finland. Harvester measurements were used as a reference for 144 trees within a single clear-cut stand. The results showed that accurate tree-level timber assortments and diameter distributions can be obtained, using terrestrial laser scanning (TLS) or a combination of TLS and airborne laser scanning (ALS). Saw log volumes were estimated with higher accuracy than pulpwood volumes. The saw log volumes were estimated with relative root-mean-squared errors of 17.5% and 16.8% with TLS and a combination of TLS and ALS, respectively. The respective accuracies for pulpwood were 60.1% and 59.3%. The differences in the bucking method used also caused some large errors. In addition, tree quality factors highly affected the bucking accuracy, especially with pulpwood volume.

  3. Alabama's timber industry - an assessment of timber product output and use, 1995

    Science.gov (United States)

    Tony G. Johnson; Jim R. Gober; J. Stephen Nix

    1998-01-01

    Output of Industrial Timber Products.Note: The reader must understand that certain terms, namely-retained, export, import, production, and receipts-have specialized meanings and relationships. unique to the Forest Inventory and Analysis Units across the country that deal with timber products output.In 1995, the combined...

  4. Petroleum price

    International Nuclear Information System (INIS)

    Chevallier, B.

    2009-01-01

    The 'AFTP' conference on 'petroleum prices' organized by Total last March, tries to explain the different aspects of the crisis we undergo for July 2007 and its consequential effects on the petroleum markets (supply, demand evolvements, impacts on reserves, prices, refining...). (O.M.)

  5. Gas prices and price process

    International Nuclear Information System (INIS)

    Groenewegen, G.G.

    1992-01-01

    On a conference (Gas for Europe in the 1990's) during the Gasexpo '91 the author held a speech of which the Dutch text is presented here. Attention is paid to the current European pricing methods (prices based on the costs of buying, transporting and distributing the natural gas and prices based on the market value, which is deducted from the prices of alternative fuels), and the transparency of the prices (lack of information on the way the prices are determined). Also attention is paid to the market signal transparency and gas-gas competition, which means a more or less free market of gas distribution. The risks of gas-to-gas competition for a long term price stability, investment policies and security of supply are discussed. Opposition against the Third Party Access (TPA), which is the program to implement gas-to-gas competition, is caused by the fear of natural gas companies for lower gas prices and lower profits. Finally attention is paid to government regulation and the activities of the European Commission (EC) in this matter. 1 fig., 6 ills., 1 tab

  6. Value of timber continues to increase

    International Nuclear Information System (INIS)

    Haluza, I.

    2007-01-01

    The state owned company, Lesy SR (state forests) enjoys great power in the timber industry. It can influence which timber processing companies in Slovakia will be successful and which will not have easy access to the raw material. It manages half of the forests in Slovakia. It is the only seller of timber in this country. Four years ago, the former cabinet appointed banker, Karol Vins, as the director of the company. And he started making changes. He centralized the timber business and thousands of people left the company. The goal was clear -to increase quality and efficiency. The economic performance of the company improved. The company has finally managed to post a profit. Last year, the government changed and so has the director of the company The former banker was replaced by a new head from a forestry research background, Jozef Mindas. He approves of some of the changes introduced by his predecessor and plans to continue implementing them, although there also those he would like to change. The new manager is not concerned regarding the big change from research where he used to work in the past to director of a big company and rejects the allegation that he was nominated by HZDS. I was approached as an expert and I won a tender. I have never been a member of a political party, he stated. He appreciates that his predecessor managed to revitalize the company, which was assisted by the positive effect of out-sourcing. But on the other hand, during transformation forests were not divided up correctly. The division into units did not always take into account the specific requirements of forestry, i.e. some employees in forest units have too much work and some, working in another forest unit, less. We have to make sure that the workload is approximately at the same level everywhere. He is aware of the fact that Lesy SR, which controls two thirds of the timber market, effectively decides which factory will succeed and which one will not. But he adds that Lesy SR do

  7. Reinforcement and recovery of timber structures

    Directory of Open Access Journals (Sweden)

    Antonio Alves Dias

    2006-02-01

    Full Text Available Preservation of timber structures is a reason for constant concern because their deterioration often involves compromising the historical patrimony, besides endangering the safety of the structure, and consequently, of their users. Many are the examples of churches, residences or other constructions where this manifestation is a fact. The technique of reinforcing structurally endangered pieces with the addition of natural or synthetic fibers, is an alternative that has been researched. In the group of synthetic fibers, fiberglass, carbon and aramid ones are included. On the other hand, it has been frequent in the restoration of old buildings, especially in Europe, the employment of materials that were not available in the past, aiming to achieve structural, acoustic and aesthetic benefits. On an existing timber structure floor, a concrete slab has been carried out, with an appropriate connection system among the parts, constituting the composite timber-concrete structures. This alternative has been considered as extraordinarily viable, because it gathers a series of convenience related with the durability and it presents better mechanic performance than conventional timber structures. In this work, the state-of-the-art of the use of fibers as structural reinforcement and of the timber-concrete composite structures, is presented.

  8. Price increase

    CERN Multimedia

    2006-01-01

    Please take note that after five years of stable prices at Restaurant No 1 a price increase will come into force on 1st January 2006. This increase has been agreed after discussions between the CSR (Comité de Surveillance des Restaurants) and the catering company Novae and will reflect the inflation rate of the last few years. In addition, a new children's menu will be introduced, as well as 'Max Havelaar' fair-trade coffee at a price of 1.70 CHF.

  9. Price increase

    CERN Multimedia

    2005-01-01

    Please take note that after five years of stable prices at Restaurant No 1 a price increase will come into force on 1st January 2006. This increase has been agreed after discussions between the CSR (Comité de Surveillance des Restaurants) and the catering company Novae and will reflect the inflation rate of the last few years. In addition, a new children's menu will be introduced as well as 'Max Havelaar' fair-trade coffee at a price of 1.70 CHF.

  10. Trade-offs between carbon stocks and timber recovery in tropical forests are mediated by logging intensity.

    Science.gov (United States)

    Roopsind, Anand; Caughlin, T Trevor; van der Hout, Peter; Arets, Eric; Putz, Francis E

    2018-03-30

    Forest degradation accounts for ~ 70% of total carbon losses from tropical forests. Substantial emissions are from selective logging, a land-use activity that decreases forest carbon density. To maintain carbon values in selectively logged forests, climate change mitigation policies and government agencies promote the adoption of reduced-impact logging (RIL) practices. However, whether RIL will maintain both carbon and timber values in managed tropical forests over time remains uncertain. In this study, we quantify the recovery of timber stocks and aboveground carbon at an experimental site where forests were subjected to different intensities of RIL (4 trees ha -1 , 8 trees ha -1 , and 16 trees ha -1 ). Our census data spans 20 years post-logging and 17 years after the liberation of future crop trees from competition in a tropical forest on the Guiana Shield, a globally important forest carbon reservoir. We model recovery of timber and carbon with a breakpoint regression that allowed us to capture elevated tree mortality immediately after logging. Recovery rates of timber and carbon were governed by the presence of residual trees (i.e., trees that persisted through the first harvest). The liberation treatment stimulated faster recovery of timber albeit at a carbon cost. Model results suggest a threshold logging intensity beyond which forests managed for timber and carbon derive few benefits from RIL, with recruitment and residual growth not sufficient to offset losses. Inclusion of the breakpoint at which carbon and timber gains outpaced post-logging mortality led to high predictive accuracy, including out-of-sample R 2 values >90%, and enabled inference on demographic changes post-logging. Our modeling framework is broadly applicable to studies that aim to quantify impacts of logging on forest recovery. Overall, we demonstrate that initial mortality drives variation in recovery rates, that the second harvest depends on old growth wood, and that timber

  11. Development of Timber Property Classification Based on the End-Use with Reference to Twenty Sri Lankan Timber Species

    Directory of Open Access Journals (Sweden)

    ND Ruwanpathirana

    2014-06-01

    Full Text Available An investigation was carried out on selected 20 timber species of Sri Lanka to study different wood properties, i.e., wood density, modulus of rapture, modulus of elasticity, compression parallel to grain, shrinkage/movement, workability (sawing, nailing, sanding and finishing, treatability of preservative, timber durability, timber texture by vessel diameter and some gross properties, timber colour and present timber uses. Based on the results, an attempt was made to classify the studied timber species into property levels. The final objective of this study was to develop relationships between the end-uses of timber and their property requirements and levels with reference to 20 Sri Lankan timber species.   Timber selection for the use in Sri Lanka is species-oriented and sometimes it is based on the traditional use. Based on wood properties of 20 Sri Lankan timber species selected, an attempt was made to recognise the most important wood properties and their levels to develop a four end-use property classification. In general, the proposed end-use property classification in this study could be differentiated as (i. for building construction, (ii. for furniture and joinery (iii. for light construction, and (iv. for miscellaneous uses. Among the selected timber species, Dipterocarpus zeylanicus is eminently suitable for under-water work. Eucalyptus microcorys is regarded as one of the best timbers for dancing floors. These specialty and causative factors of timber, however, must be explored and documented in order to prepare end-use property classification for miscellaneous use.

  12. Economic implications of manufacturing sawed ties and timbers

    Science.gov (United States)

    Lawrence D. Garrett; Lawrence D. Garrett

    1969-01-01

    The purpose of this paper is to discuss those factors that affect the profitability of manufacturing timbers and show that the combined manufacture of both lumber and timbers will provide a greater daily income than the manufacture of lumber alone.

  13. Methodology for safety evaluation of existing timber elements

    OpenAIRE

    Sousa, Hélder S.

    2013-01-01

    Tese de doutoramento em Engenharia Civil The past decades have seen a renewed interest in timber research related topics. As instance, timber engineering is not only confined to the design of new construction with innovative wood based products, but also an increasing awareness for the preservation of existing timber structures is visible in nowadays society. Therefore, arises the need for a better understanding of timber performance as a construction material aiming at a bette...

  14. Freemium Pricing

    DEFF Research Database (Denmark)

    Runge, Julian; Wagner, Stefan; Claussen, Jörg

    Firms commonly run field experiments to improve their freemium pricing schemes. However, they often lack a framework for analysis that goes beyond directly measurable outcomes and focuses on longer term profit. We aim to fill this gap by structuring existing knowledge on freemium pricing...... into a stylized framework. We apply the proposed framework in the analysis of a field experiment that contrasts three variations of a freemium pricing scheme and comprises about 300,000 users of a software application. Our findings indicate that a reduction of free product features increases conversion as well...... as viral activity, but reduces usage – which is in line with the framework’s predictions. Additional back-of-the-envelope profit estimations suggest that managers were overly optimistic about positive externalities from usage and viral activity in their choice of pricing scheme, leading them to give too...

  15. Price of forest chips decreasing

    International Nuclear Information System (INIS)

    Hakkila, P.

    2001-01-01

    Use of forest chips was studied in 1999 in the national Puuenergia (Wood Energy) research program. Wood combusting heating plants were questioned about are the main reasons restricting the increment of the use of forest chips. Heating plants, which did not use forest chips at all or which used less than 250 m 3 (625 bulk- m 3 ) in 1999 were excluded. The main restrictions for additional use of forest chips were: too high price of forest chips; lack of suppliers and/or uncertainty of deliveries; technical problems of reception and processing of forest chips; insufficiency of boiler output especially in winter; and unsatisfactory quality of chips. The price of forest chips becomes relatively high because wood biomass used for production of forest chips has to be collected from wide area. Heavy equipment has to be used even though small fragments of wood are processed, which increases the price of chips. It is essential for forest chips that the costs can be pressed down because competition with fossil fuels, peat and industrial wood residues is hard. Low market price leads to the situation in which forest owner gets no price of the raw material, the entrepreneurs operate at the limit of profitability and renovation of machinery is difficult, and forest chips suppliers have to sell the chips at prime costs. Price of forest chips has decreased significantly during the past decade. Nominal price of forest chips is now lower than two decades ago. The real price of chips has decreased even more than the nominal price, 35% during the past decade and 20% during the last five years. Chips, made of small diameter wood, are expensive because the price includes the felling costs and harvesting is carried out at thinning lots. Price is especially high if chips are made of delimbed small diameter wood due to increased the work and reduced amount of chips. The price of logging residue chips is most profitable because cutting does not cause additional costs. Recovery of chips is

  16. Petroleum price

    International Nuclear Information System (INIS)

    Maurice, J.

    2001-01-01

    The oil market is the most volatile of all markets, with the exception of the Nasdaq. It is also the biggest commodity market in the world. Therefore one cannot avoid forecasting oil prices, nor can one expect to avoid the forecasting errors that have been made in the past. In his report, Joel Maurice draws a distinction between the short term and the medium-long term in analysing the outlook for oil prices. (author)

  17. Architectural and structural qualities in timber joints

    DEFF Research Database (Denmark)

    Christensen, Jesper Thøger; Christensen, Mogens Fiil; Damkilde, Lars

    2016-01-01

    Design of joints in timber structures is crucial to reach both elegant and structural efficient designs. Design of joints should therefore be an integral part of the conceptual design phase. Traditionally this is not the case, and joints are often solely designed and analysed in the engineering...... but also increase timbers competitiveness in the building industry. The paper is part of an ongoing research project aiming at providing tools for an integrated design process for timber structures. The focus of the paper is to identify how structure and its joints contributes to architecture and vice...... design phase. The result is joints that function structurally but do not add value to the design, and may even compromise the architectural ideas. With an approach, integrating both structural and architectural design from the beginning, one should not only gain better structures and architecture...

  18. Probabilistic Modelling of Timber Material Properties

    DEFF Research Database (Denmark)

    Nielsen, Michael Havbro Faber; Köhler, Jochen; Sørensen, John Dalsgaard

    2001-01-01

    The probabilistic modeling of timber material characteristics is considered with special emphasis to the modeling of the effect of different quality control and selection procedures used as means for grading of timber in the production line. It is shown how statistical models may be established...... on the basis of the same type of information which is normally collected as a part of the quality control procedures and furthermore, how the efficiency of different control procedures may be compared. The tail behavior of the probability distributions of timber material characteristics play an important role...... such that they may readily be applied in structural reliability analysis and the format appears to be appropriate for codification purposes of quality control and selection for grading procedures...

  19. 36 CFR 223.62 - Timber purchaser road construction credit.

    Science.gov (United States)

    2010-07-01

    ... § 223.62 Timber purchaser road construction credit. Appraisal may also establish stumpage value as if... timber is appraised and sold on such basis, purchaser credit for road construction, not to exceed the estimated construction cost of such roads or other developments specified in the timber sale contract, shall...

  20. Safety of timber : An analysis of quality control options

    NARCIS (Netherlands)

    Kovryga, A.; Stapel, P.; Van de Kuilen, J.W.G.

    2014-01-01

    The quality assurance of timber properties is important for the safety of timber structures. In the current study, the quality control options of timber are analysed under the prism of the different growth regions. Therefore, these options - machine and output control - are simulated in accordance

  1. Modified traditional Japanese timber joint system with retrofitting abilities

    NARCIS (Netherlands)

    Shiratori, T.; Komatsu, K.; Leijten, A.J.M.

    2008-01-01

    Embedment is a key feature of timber joints envisioned as the ultimate solution in avoiding the devastating full collapse of timber structures in seismic countries. The Japanese traditional timber post-and-beam structural system utilizes moment-resisting joints based on embedment. Despite the

  2. Effect of timber supplies on the efficiency of coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Kulish, S A; Ponikarov, V D

    1977-01-01

    An analysis is made of the system of supplying coal mining production associations with timber materials. The potential for greater efficiency in the use and processing of timber is indicated. The possibility of using methods of mathematical modelling and forecasting to improve the efficiency of supplying timber to coal associations is demonstrated. 1 table.

  3. Robustness Analysis of Timber Truss Structure

    DEFF Research Database (Denmark)

    Rajčić, Vlatka; Čizmar, Dean; Kirkegaard, Poul Henning

    2010-01-01

    The present paper discusses robustness of structures in general and the robustness requirements given in the codes. Robustness of timber structures is also an issues as this is closely related to Working group 3 (Robustness of systems) of the COST E55 project. Finally, an example of a robustness...... evaluation of a widespan timber truss structure is presented. This structure was built few years ago near Zagreb and has a span of 45m. Reliability analysis of the main members and the system is conducted and based on this a robustness analysis is preformed....

  4. Timber Elements: Traditional and Modern Strengthening Techniques

    Directory of Open Access Journals (Sweden)

    Raluca Hohan

    2010-01-01

    Full Text Available The main idea of this paper is to analyse the means for the rehabilitation of our cultural heritage timber structures. Several methods together with their application techniques are described, and also, the reasons for what these strengthening operations become imminent at a point. First of all, the necessity of the timber structural elements strengthening is explained through a short presentation of the factors which are degrading the material. Then, certain precautions and strengthening procedures are presented, all involving the usage of traditional materials like wood, metal, or concrete, and of modern materials like fiber reinforced polymeric composite.

  5. Robustness of Long Span Reciprocal Timber Structures

    DEFF Research Database (Denmark)

    Balfroid, Nathalie; Kirkegaard, Poul Henning

    2011-01-01

    engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper makes a discussion of such robustness issues related to the future development of reciprocal timber structures. The paper concludes that these kind of structures can have...... a potential as long span timber structures in real projects if they are carefully designed with respect to the overall robustness strategies.......Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. The interest has also been facilitated due to recently severe structural failures...

  6. Statistical Analysis of Data for Timber Strengths

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2003-01-01

    Statistical analyses are performed for material strength parameters from a large number of specimens of structural timber. Non-parametric statistical analysis and fits have been investigated for the following distribution types: Normal, Lognormal, 2 parameter Weibull and 3-parameter Weibull...... fits to the data available, especially if tail fits are used whereas the Log Normal distribution generally gives a poor fit and larger coefficients of variation, especially if tail fits are used. The implications on the reliability level of typical structural elements and on partial safety factors...... for timber are investigated....

  7. Possible Demands for Eastern Hardwoods Resulting from Harvest Restrictions in the Pacific

    Science.gov (United States)

    Janice K. Wiedenbeck; Philip A. Araman

    1993-01-01

    Efforts to conserve the habitat of the northern spotted owl in the Pacific Northwest have placed softwood timber supplies under a great deal of pressure and driven up the price of softwood lumber. Hardwoods could meet some of the demand for products that have previously been manufactured from softwood species. Hardwood structural lumber may soon become an economically...

  8. Wind energy harvesting with a piezoelectric harvester

    International Nuclear Information System (INIS)

    Wu, Nan; Wang, Quan; Xie, Xiangdong

    2013-01-01

    An energy harvester comprising a cantilever attached to piezoelectric patches and a proof mass is developed for wind energy harvesting, from a cross wind-induced vibration of the cantilever, by the electromechanical coupling effect of piezoelectric materials. The vibration of the cantilever under the cross wind is induced by the air pressure owing to a vortex shedding phenomenon that occurs on the leeward side of the cantilever. To describe the energy harvesting process, a theoretical model considering the cross wind-induced vibration on the piezoelectric coupled cantilever energy harvester is developed, to calculate the charge and the voltage from the harvester. The influences of the length and location of the piezoelectric patches as well as the proof mass on the generated electric power are investigated. Results show that the total generated electric power can be as high as 2 W when the resonant frequency of the cantilever harvester is close to the vortex shedding frequency. Moreover, a value of total generated electric power up to 1.02 W can be practically realized for a cross wind with a variable wind velocity of 9–10 m s −1 by a harvester with a length of 1.2 m. This research facilitates an effective and compact wind energy harvesting device. (paper)

  9. Marketplace pricing

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    As discussed in this chapter, interest in marketplace pricing has been increasing in recent years, reflecting the societal trend toward substituting competition for regulation where appropriate. Competition is valuable because it encourages utilities to make efficient decisions with a minimum of regulatory intervention. It enhances efficiency through the incentive for innovation by the regulated companies and by increasing the likelihood they will come forward with proposals for better services, lower prices or both. Ultimately, consumers are beneficiaries. Marketplace pricing is emblematic of the view that the degree of regulation should reflect the degree of market power, that workably competitive markets should be allowed to operate with as little regulatory interference as possible. The Edison Electric Institute has made perhaps the most detailed proposal on marketplace pricing. It and others perceive numerous benefits from this method of pricing transmission services. Given the undeniable market power resulting from line ownership, FERC has emphasized the need to find a workably competitive market before approving such proposals. The ability to make this distinction without a full-blown antitrust review for every transaction is questionable, and FERC has yet to provide generic guidance. Finally, FERC's legal ability to depart from cost-based standards is questionable

  10. Rent-seeking and timber rights allocation in Ghana

    DEFF Research Database (Denmark)

    Carlsen, Kirsten; Hansen, Christian Pilegaard

    2014-01-01

    This paper describes types, processes and importance of rent-seeking in the allocation of timber rights in Ghana. It is based on an analysis of 30 interviews with large-, medium- and small-scale timber firms, as well as government officials and timber industry organizations in Ghana. The paper...... documents that timber rights allocation is associated with both bureaucratic and political corruption. The latter comes in two forms. First, the findings suggest that well-established relationships exist between politicians and senior bureaucrats on the one side and large-scale timber firms on the other...

  11. Comportamento dos preços dos insumos agrícolas da cana-de-açúcar: safra 2016/17 = Agricultural inputs prices behavior of sugar cane: harvest 2016/17

    Directory of Open Access Journals (Sweden)

    Aline Bigaton

    2017-10-01

    Full Text Available Esta publicação apresenta as variações de preços dos produtos utilizados como insumos agrícolas na produção de cana-de-açúcar nas principais regiões produtoras do estado de São Paulo, entre os meses de dezembro de 2016 e janeiro de 2016. As variações de preços mais expressivas foram representadas pela classe dos inseticidas, no painel de Barretos e pelos corretivos, no painel de Araçatuba. Apesar disso, a classe de fertilizantes também apresenta variações expressivas em todos os painéis, sendo que estes insumos foram os mais representativos na composição dos custos de produção. A representatividade dos custos com insumos para a produção da cultura com relação ao total recebido por hectare apresentou uma média próxima dos 14%, sendo a região de Paulo de Faria a que apresenta maior representatividade (25%. = This publication presents the price variations of the products used as agricultural inputs in the production of sugarcane in the main producing regions of the state of São Paulo, between December 2016 and January 2016. The most significant price variations were represented by the class of insecticides, in the panel of Barretos and by the corrective ones, in the panel of Araçatuba. Nevertheless, the fertilizer class also presents significant variations in all panels, and these inputs are the most representative in the composition of production costs. The representativeness of input costs for crop production in relation to the total received per hectare showed an average around 14%, with the region of Paulo de Faria being the most representative (25%.

  12. Standard plans for timber bridge superstructures

    Science.gov (United States)

    James P. Wacker; Matthew S. Smith

    2001-01-01

    These standardized bridge plans are for superstructures consisting of treated timber. Seven superstructure types are includes: five longitudinal and two transverse deck systems. Both HS520 and HS25 loadings are included, along with L/360 and L/500 deflection criteria.

  13. Timber resource of Minnesota's Prairie unit, 1977.

    Science.gov (United States)

    Jerold T. Hahn; W. Brad Smith

    1980-01-01

    The fourth inventory of Minnesota's Prairie Unit shows that although commercial forest area decreased 31.7% between 1962 and 1977, growing-stock volume increased 22%. This report gives statistical highlights and contains detailed tables of forest area as well as timber volume, growth, mortality, ownership, and use.

  14. Projecting Timber Inventory at the Product Level

    Science.gov (United States)

    Lawrence Teeter; Xiaoping Zhou

    1999-01-01

    Current timber inventory projections generally lack information on inventory by product classes. Most models available for inventory projection and linked to supply analyses are limited to projecting aggregate softwood and hardwood. The research presented describes a methodology for distributing the volume on each FIA (USDA Forest Service Forest Inventory and Analysis...

  15. Residual load carrying capacity of timber joints

    NARCIS (Netherlands)

    Kuilen, J.W.G. van de

    1999-01-01

    Timber joints that have been preloaded for 2 to 8 years have been short term tested in accordance with EN 26891. The applied load levels varied between 30% and 50% of the average short term strength. The study comprised nailed, toothed-plate and split-ring joints. All joints were made of spruce and

  16. Commercial lumber, round timbers, and ties

    Science.gov (United States)

    David E. Kretschmann

    2010-01-01

    When sawn, a log yields round timber, ties, or lumber of varying quality. This chapter presents a general discussion of grading, standards, and specifications for these commercial products. In a broad sense, commercial lumber is any lumber that is bought or sold in the normal channels of commerce. Commercial lumber may be found in a variety of forms, species, and types...

  17. Grading timber and glued structural members

    Science.gov (United States)

    David E. Kretschmann; Roland Hernandez

    2006-01-01

    Because of its biological nature, which is influenced by many factors as discussed in Chapter 6, the quality of timber is enormously variable. Therefore, some sort of arrangement or classification must be undertaken prior to its use, in order to get the most out of this valuable resource. It is obvious that not all lumber can be used for the same purposes because not...

  18. Pocket Checklists of Indonesian timber trees

    NARCIS (Netherlands)

    Prawira, Soewanda A.; Tantra, I.G.M.; Whitmore, T.C.

    1984-01-01

    Indonesia as yet does not have a comprehensive account of the forest trees which reach timber size (35 cm dbh = 14 inch or 105 cm gbh = 42 inch). A project has been started in August 1983 by the Botany Section of the Forest Research Institute in Bogor, Indonesia, to prepare pocket checklists of the

  19. IMPACTS OF TIMBER LEGALITY VERIFICATION SYSTEM IMPLEMENTATION ON THE SUSTAINABILITY OF TIMBER INDUSTRY AND PRIVATE FOREST

    Directory of Open Access Journals (Sweden)

    Elvida Yosefi Suryandari

    2017-04-01

    Full Text Available International market requires producers to proof the legality of their wood products to address the issues of illegal logging and illegal trade. Timber Legality Verification System (TLVS has been prepared by the Government of Indonesia that covering the upstream and downstream wood industries. This paper aims to evaluate gaps in the implementation of TLVS policy and its impact on the sustainability of timber industry. This study was using gap, descriptive and costs-structure analyzes. The study was conducted in three provinces, namely: DKI Jakarta, West Java and D.I. Yogyakarta. Research found that the effectiveness of the TLVS implementation was low due to relatively rapid policy changes. This situation became disincetive for investments in timber business. Private sector perceived that TLVS policy should be applied in the upstream of timber business. Hence, the industry and market in the downstream have not been fully support to this system. Furthermore, TLVS policy implementation was considered ineffective by timber industry as well as private forest managers, especially by micro industry and smallholder private forests. This situation threatened the sustainability of timber industry and private forests. Therefore, Institutions should be strengthened in order to improve the quality of human resources and the competitiveness of products.

  20. Electricity pricing

    International Nuclear Information System (INIS)

    Wijayatunga, P.D.C.

    1994-01-01

    Electricity pricing in most countries, especially in the developing world, has been determined by traditional accounting criteria where it raises revenue requirements to cover the operating costs and a return on past and future capital investments in possible power systems. The use of economic principles to improve the total economic efficiency in the electricity industry is discussed. Basic marginal cost theory, long run marginal costing (LRMC) cost categories and rating periods, marginal capacity costs, marginal energy costs, consumer costs, short run marginal costing (SRMC), marginal cost of fuel, marginal cost of network losses, market clearing price, value of unserved energy and network quality of supply cost are discussed

  1. Post-harvest physiology

    Science.gov (United States)

    Weather and management constraints, as well as the intended use of the harvested forage, all influence the forage harvest system selected by the producer. Generally, maximum retention of dry matter from harvested forage crops is achieved at moistures intermediate between the standing fresh crop and ...

  2. Early response of ground layer plant communities to wildfire and harvesting disturbance in forested peatland ecosystems in northern Minnesota, USA

    Science.gov (United States)

    Erika R. Rowe; Anthony W. D' Amato; Brian J. Palik; John C. Almendinger

    2017-01-01

    A rare, stand-replacing fire in northern Minnesota, USA provided the opportunity to compare the effects of wildfire and timber harvesting in two peatland forest communities, nutrient-poor black spruce (Picea mariana) bogs (BSB) and nutrient-rich tamarack (Larix laricina) swamps (RTS). We found the response between the two...

  3. Cost and productivity of new technology for harvesting and in-woods processing small-diameter trees.

    Science.gov (United States)

    Michael B Lambert; James O. Howard

    1990-01-01

    A study was conducted on the productivity and cost of an integrated harvesting and processing system operating in small-diameter timber (western hemlock-type) on the Olympic Peninsula of western Washington. The system uses a new steep-slope fellerbuncher, a clam-bunk grapple-skidder (forwarder), a prototype chain-flail debarker delimber, a chipper, a conveyor system,...

  4. Response of herbaceous plant community diversity and composition to overstorey harvest within riparian management zones in Northern Hardwoods

    Science.gov (United States)

    Eric K. Zenner; Michelle A. Martin; Brian J. Palik; Jerilynn E. Peck; Charles R. Blinn

    2013-01-01

    Partial timber harvest within riparian management zones (RMZs) may permit active management of riparian forests while protecting stream ecosystems, but impacts on herbaceous communities are poorly understood. We compared herbaceous plant community abundance, diversity and composition in RMZs along small streams in northern Minnesota, USA, among four treatments before...

  5. Nutrient uptake and community metabolism in streams draining harvested and old-growth watersheds: A preliminary assessment

    Science.gov (United States)

    Brian H. Hill; Frank H. McCormick

    2004-01-01

    The effect of timber harvesting on streams is assessed using two measures of ecosystem function: nutrient spiraling and community metabolism. This research is being conducted in streams of the southern Appalachian Mountains of North Carolina, the Ouachita Mountains of Arkansas, the Cascade Mountains of Oregon, and the redwood forests of northern California, in order to...

  6. Private forest landowners’ harvest and regeneration decisions—effect of proximity to primary wood-using mills

    Science.gov (United States)

    Consuelo Brandeis

    2015-01-01

    Ownership of the U.S. southern timberland rests largely on private forest landowners’ hands. As such, their harvest and regeneration choices can significantly impact the region’s roundwood supply. In most cases, private forest landowners do not consider timber production among the top reasons for holding their lands. However, most research indicates that favorable...

  7. The secret life of microbes: soil bacteria and fungi undaunted by the harvesting of fire-killed trees

    Science.gov (United States)

    Paul Meznarich; Jane Smith; Tara Jennings

    2013-01-01

    Soil health is fundamental to ecosystem health. Disturbances such as fire and timber harvesting can affect the abundance, activity, and composition of soil microbial communities and thus affect soil productivity. In response to forest managers, scientists with the Pacific Northwest Research Station compared health and productivity indicators between soils disturbed by...

  8. Defoliation and bark harvesting affect life-history traits of a tropical tree

    DEFF Research Database (Denmark)

    Gaoue, Orou; Horvitz, Carol; Ticktin, Tamara

    2013-01-01

    Selectively harvesting whole individuals in managed populations (e.g. fisheries, hunting) has substantial effects on life expectancy and age at maturity. Although demographic rates of trees are impacted by recurrent harvest of plant organs (e.g. fruit, leaf, bark) known as non-timber forest...... of life expectancy to perturbation of vital rates to the elasticities of population growth rate, emphasizing how the two kinds of elasticity address distinct biological issues and management goals. Life expectancy was shorter and reproduction delayed in the dry than in the moist region, indicating a cost...... of drought to life-history traits. Harvesting at constant rates only affects (increased) life expectancy in the moist region and (reduced) age at first reproduction in the dry region. Models in which harvest intensity varies stochastically over time show results similar to those with constant harvesting rate...

  9. Applying of whole-tree harvesting method; Kokopuujuontomenetelmaen soveltaminen aines- ja energiapuun hankintaan

    Energy Technology Data Exchange (ETDEWEB)

    Vesisenaho, T [VTT Energy, Jyvaeskylae (Finland); Liukkonen, S [VTT Manufacturing Technology, Espoo (Finland)

    1997-12-01

    The objective of this project is to apply whole-tree harvesting method to Finnish timber harvesting conditions in order to lower the harvesting costs of energy wood and timber in spruce-dominant final cuttings. In Finnish conditions timber harvesting is normally based on the log-length method. Because of small landings and the high level of thinning cuttings, whole-tree skidding methods cannot be utilised extensively. The share of stands which could be harvested with whole-tree skidding method showed up to be about 10 % of the total harvesting amount of 50 mill. m{sup 3}. The corresponding harvesting potential of energy wood is 0,25 Mtoe. The aim of the structural measurements made in this project was to get information about the effect of different hauling methods into the structural response of the tractor, and thus reveal the possible special requirements that the new whole-tree skidding places forest tractor design. Altogether 7 strain gauge based sensors were mounted into the rear frame structures and drive shafts of the forest tractor. Five strain gauges measured local strains in some critical details and two sensors measured the torque moments of the front and rear bogie drive shafts. Also the revolution speed of the rear drive shaft was recorded. Signal time histories, maximum peaks, Time at Level distributions and Rainflow distributions were gathered in different hauling modes. From these, maximum values, average stress levels and fatigue life estimates were calculated for each mode, and a comparison of the different methods from the structural point of view was performed

  10. Framework for Robustness Assessment of Timber Structures

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard

    2011-01-01

    This paper presents a theoretical framework for the design and analysis of robustness of timber structures. This is actualized by a more4 frequent use of advanced types of timber structures with limited redundancy and serious consequences in the case of failure. Combined with increased requirements...... to efficiency in design and execution followed by increased risk of human errors has made the need of requirements to robustness of new structures essential. Further, the collapse of the Ballerup Super Arena, the bad Reichenhall Ice-Arena and a number of other structural systems during the last 10 years has...... increased the interest in robustness. Typically, modern structural design codes require that ‘the consequence of damages to structures should not be disproportional to the causes of the damages’. However, although the importance of robustness for structural design is widely recognized, the code requirements...

  11. Timber Curtain: Designing with material capabilities

    DEFF Research Database (Denmark)

    Lahmy, Maya; Larsen, Niels Martin

    2015-01-01

    of the generative phase to fabrication of the artefact. Brought together by various conceptual and structural elements the Timber Curtain forms a 4.5 x 2.5 x 0.5 m construct of assembled wood components, digitally crafted through advanced production techniques. Concerned with materiality and processing of the wood......Timber Curtain explores relations between digital precision and material indeterminacy. It is an installation engaging spatially through its presence as a 1:1 architectural component as well as it is exploring novel technologies in the architectural design process from the very beginning...... an associative digital model that could gather and compute in put from material behaviour and out put manufacturing data was scripted. This method enables material capacity to be pushed to the limit of its performance allowing novel sensuous and structural qualities to emerge. The method is developed with use...

  12. Robustness Assessment of Spatial Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning

    2012-01-01

    Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures many modern buildi...... to robustness of spatial timber structures and will discuss the consequences of such robustness issues related to the future development of timber structures.......Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures many modern building...... codes consider the need for robustness of structures and provide strategies and methods to obtain robustness. Therefore a structural engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper summaries issues with respect...

  13. Probabilistic Modeling of Graded Timber Material Properties

    DEFF Research Database (Denmark)

    Faber, M. H.; Köhler, J.; Sørensen, John Dalsgaard

    2004-01-01

    The probabilistic modeling of timber material characteristics is considered with special emphasis to the modeling of the effect of different quality control and selection procedures used as means for quality grading in the production line. It is shown how statistical models may be established...... on the basis of the same type of information which is normally collected as a part of the quality control procedures and furthermore, how the efficiency of different control procedures may be quantified and compared. The tail behavior of the probability distributions of timber material characteristics plays...... such that they may readily be applied in structural reliability analysis and their format appears to be appropriate for codification purposes of quality control and selection for grading procedures....

  14. Timber drying kilns using solar energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-15

    The objective of this project was to research the potential for solar kilns for drying timber in tropical countries (Guyana, Honduras and Belize) and produce a manual which will provide the knowledge necessary to build and operate a solar kiln. The main output of the project is the manual Solar Heated Timber Drying Kilns - a Manual on their Design and Operation. The manual covers:- background information; selection of construction materials; methods of kiln construction; kiln operation and maintenance procedure. The manual has been designed to provide the necessary knowledge and confidence to build and operate a solar kiln, and ultimately benefit from an improved product. Specifically, the manual will benefit small building construction units, furniture and joinery manufacturers and sawmill operators in developing and developed countries worldwide. (author)

  15. SUSTAINABLE MANAGEMENT OF CAMEROON FORESTS RESOURCES: PROVIDING TIMBER WASTE TO THE POOR POPULATIONS AS ALTERNATIVE SOURCE OF ENERGY

    Directory of Open Access Journals (Sweden)

    Serge Benjamin Noumo Foko

    2014-01-01

    Full Text Available Cameroon is covered by about 20 million hectares of forests. Timber exploitation is the second source of external income after petroleum. Besides, Cameroon’s forest has several other functions. Yet the threat to the very existence and survival of this forest is rapidly increasing due to overexploitation by logging companies and for firewood. Despite its usefulness, a substantial volume of the wood felled by timber exploiters is abandoned as waste to rot. This waste can be used as firewood by households even for building and making of furniture by small-scale users like carpenters if they had access to it. This paper encourages the use of timber waste as an alternative to kerosene, which has become very expensive and unaffordable due to the general rise in the price of petroleum products in recent years. The overexploitation of forests can therefore be limited by putting the waste timber into use. It will go along to reduce freshly cut wood which is usually cut illegally and uncontrollably and which is a major source of depletion of forest resources. This project, once achieved will forever last because it will always generate revenue to the groups involve in the collection and the distribution of forest waste which will make money from sales even if they were to sell cheaper since the major cost is transportation and the waste wood is also cheap to obtain from the logging companies or even costless since they have less interest in it.

  16. Timbered masonry for earthquake resistance in Europe

    OpenAIRE

    Dutu, A.; Gomes Ferreira, J.; Guerreiro, L.; Branco, F.; Gonçalves, A. M.

    2012-01-01

    Europe is a continent that is subject to significant seismic activity. Thus, the buildings’ seismic behaviour must be analysed, including not only the new structures, designed under more rigorous codes, but also older ones. This article examines a traditional type of building that uses timber frame/masonry, which is found in Portugal, Turkey, France, England, Greece, Romania, Italy, Spain, Germany and Scandinavia. Although the structures differ in terms of construction details, their struc...

  17. Timbered masonry for earthquake resistance in Europe

    OpenAIRE

    Dutu, A.; Gomes Ferreira, J.; Guerreiro, L.; Branco, F.; Gonçalves, A. M.

    2012-01-01

    Europe is a continent that is subject to significant seismic activity. Thus, the buildings’ seismic behaviour must be analysed, including not only the new structures, designed under more rigorous codes, but also older ones. This article examines a traditional type of building that uses timber frame/masonry, which is found in Portugal, Turkey, France, England, Greece, Romania, Italy, Spain, Germany and Scandinavia. Although the structures differ in terms of construction details, their str...

  18. Roof timber for fortifying mining works

    Energy Technology Data Exchange (ETDEWEB)

    Shirokov, A P; Kuntsevich, V IK; Pishchulin, V V; Seryi, A M; Volkov, P A

    1981-05-15

    The roof timber for fortifying mining works includes spring-mounted hinged elements made from a special rolled metal. In order to increase the carrying capacity of the support by increasing the deformation threshold, the springs are mounted by their expanded section to the lower side of the hinge; their ends are connected in turn to the elements made from the special rolled metal on both sides of the hinge.

  19. Timber joints under long-term loading

    DEFF Research Database (Denmark)

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...... integral nail-plates and nailed steel and plywood gussets. The report is intended for designers and researchers in timber engineering....

  20. CONTEMPORARY CONSTRUCTIONS OF TIMBER PASSIVE HOUSES IN SLOVENIA

    Directory of Open Access Journals (Sweden)

    Manja Kitek Kuzman

    2013-12-01

    Full Text Available Energy efficiency is essential in the efforts to achieve a 20% reduction of primary power consumption by 2020. It is widely recognized that the potential of energy saving in buildings is large. Considering the tendencies of energy production and price, it is becoming urgent to reduce energy consumption in buildings. The choice of materials for a building with a high energy efficiency becomes much more important and strategies for reducing the use of primary energy for the production of materials and components becomes key. Renewable building materials should already be integrated into the early phases of building planning. The positive trend towards wooden construction is dictated by international guidelines, where a wooden building is an important starting point, not only for low-energy, but also lowemission building with exceptional health and safety aspects. In Europe, the most comprehensive and widely used is a concept of ultralow energy house, more precisely, the passive house concept. Most Slovenian buildings combine contemporary styling with a degree of energy efficiency that comes close to passive house standards. It is widely recognized that the Slovenian construction industry is relatively advanced in the field of low energy buildings. In the light of the growing importance of energy-efficient building methods, it could be said that timber passive house would play an increasingly important role in the future.

  1. Global timber investments, wood costs, regulation, and risk

    International Nuclear Information System (INIS)

    Cubbage, Frederick; Koesbandana, Sadharga; Gonzalez, Ronalds; Carrero, Omar; MacIntyre, Charles; Abt, Robert; Phillips, Richard; Mac Donagh, Patricio; Rubilar, Rafael; Balmelli, Gustavo; Olmos, Virginia Morales; De La Torre, Rafael; Murara, Mauro; Hoeflich, Vitor Afonso; Kotze, Heynz; Frey, Gregory; Adams, Thomas; Turner, James; Lord, Roger; Huang, Jin; McGinley, Kathleen

    2010-01-01

    We estimated financial returns and wood production costs in 2008 for the primary timber plantation species. Excluding land costs, returns for exotic plantations in almost all of South America - Brazil, Argentina, Uruguay, Chile, Colombia, Venezuela, and Paraguay - were substantial. Eucalyptus species returns were generally greater than those for Pinus species in each country, with most having Internal Rates of Return (IRRs) of 20% per year or more, as did teak. Pinus species in South America were generally closer to 15%, except in Argentina, where they were 20%. IRRs were less, but still attractive for plantations of coniferous or deciduous species in China, South Africa, New Zealand, Indonesia, and the United States, ranging from 7% to 12%. Costs of wood production at the cost of capital of 8% per year were generally cheapest for countries with high rates of return and for pulpwood fiber production, which would favor vertically integrated firms in Latin America. But wood costs at stumpage market prices were much greater, making net wood costs for open market wood more similar among countries. In the Americas, Chile and Brazil had the most regulatory components of sustainable forest management, followed by Misiones, Argentina and Oregon in the U.S. New Zealand, the United States, and Chile had the best rankings regarding risk from political, commercial, war, or government actions and for the ease of doing business. Conversely, Venezuela, Indonesia, Colombia, and Argentina had high risk ratings, and Brazil, Indonesia, and Venezuela were ranked as more difficult countries for ease of business. (author)

  2. Global timber investments, wood costs, regulation, and risk

    Energy Technology Data Exchange (ETDEWEB)

    Cubbage, Frederick; Koesbandana, Sadharga; Gonzalez, Ronalds; Carrero, Omar; MacIntyre, Charles; Abt, Robert; Phillips, Richard [Forestry and Environmental Resources, North Carolina State University, Raleigh, NC (United States); Mac Donagh, Patricio [Universidad Nacional de Misiones (UNAM), Lisandro de la Torre s/n, CP 3380, Eldorado, Misiones (Argentina); Rubilar, Rafael [Universidad de Concepcion, Victoria 631, Casilla 160-C - Correo 3, Concepcion (Chile); Balmelli, Gustavo [Instituto Nacional de Investigacion Agropecuria, INIA Tacuarembo, Ruta 5, Km 386, Tacuarembo (Uruguay); Olmos, Virginia Morales [Weyerhaeuser Company, La Rosa 765, Melo (Uruguay); De La Torre, Rafael [CellFor, 247 Davis Street, Athens, GA (United States); Murara, Mauro [Universidade do Contestado, R. Joaquim Nabuco, 314 Bairro Cidade Nova, Porto Uniao, Santa Catarina (Brazil); Hoeflich, Vitor Afonso [Universidade Federal do Parana, Av. Pref. Lothario Meissner, 900, 80210-170, Jardim Botanico, Curitiba, Parana (Brazil); Kotze, Heynz [Komatiland Forests (Pty) Ltd, P.O. Box 14228, Nelspruit (South Africa); Frey, Gregory [World Bank, 1818 H. Street NW, Washington, DC (United States); Adams, Thomas; Turner, James [New Zealand Forest Research Institute Ltd., Scion, 49 Sala St., Rotorua (New Zealand); Lord, Roger [Mason, Bruce, and Girard, Inc., 707 SW Washington St., Portland, Oregon (United States); Huang, Jin [Abt Associates, 4550 Montgomery Avenue, Bethesda, MD (United States); McGinley, Kathleen [International Institute of Tropical Forestry, USDA Forest Service, c/o 920 Main Campus Dr. Suite 300, Raleigh, NC (United States)

    2010-12-15

    We estimated financial returns and wood production costs in 2008 for the primary timber plantation species. Excluding land costs, returns for exotic plantations in almost all of South America - Brazil, Argentina, Uruguay, Chile, Colombia, Venezuela, and Paraguay - were substantial. Eucalyptus species returns were generally greater than those for Pinus species in each country, with most having Internal Rates of Return (IRRs) of 20% per year or more, as did teak. Pinus species in South America were generally closer to 15%, except in Argentina, where they were 20%. IRRs were less, but still attractive for plantations of coniferous or deciduous species in China, South Africa, New Zealand, Indonesia, and the United States, ranging from 7% to 12%. Costs of wood production at the cost of capital of 8% per year were generally cheapest for countries with high rates of return and for pulpwood fiber production, which would favor vertically integrated firms in Latin America. But wood costs at stumpage market prices were much greater, making net wood costs for open market wood more similar among countries. In the Americas, Chile and Brazil had the most regulatory components of sustainable forest management, followed by Misiones, Argentina and Oregon in the U.S. New Zealand, the United States, and Chile had the best rankings regarding risk from political, commercial, war, or government actions and for the ease of doing business. Conversely, Venezuela, Indonesia, Colombia, and Argentina had high risk ratings, and Brazil, Indonesia, and Venezuela were ranked as more difficult countries for ease of business. (author)

  3. Remote sensing and GIS application in best harvest management planning in Sultan Idris Shah Forestry Education Centre (SISFEC), UPM

    International Nuclear Information System (INIS)

    Norizah, K; Hasmadi, I M; Misnah, E O

    2014-01-01

    This study was carried out in UPM's field centre for education and research. First harvested in the 1960's, this secondary lowland dipterocarp forest should through the second harvest rotation. At the age of 50 years, the timber quality and revenue might decreases. The trees are also a risk to students, researchers and publics. Maintaining the ecosystem sustainability for the continual purpose of education and research, harvesting operation must be commenced by best harvest planning management. Respecting to this study, the application of remotely sensed imagery with the integration of available maps and associated databases have been used. Initially, the interactive feature of SISFEC have been developed in digital terrain model (DTM) identifying the physical and cadastral land classifications information. Several criteria derived from the DTM have been buffered subjected to harvesting practice and mitigation measures for sustainable timber harvesting operation. Eventually, the suitable harvest zones have been determined with total 677.7 ha and 4 km of new extraction road was proposed connecting to the centre of harvesting operation area. Overall, this study has been conducted in respecting the main purpose of this forest. Balance between the sustainability of the ecosystem and development needs of forest and communities are taken into consideration in strategic planning which is vital for continual usage

  4. Fog Harvesting with Harps.

    Science.gov (United States)

    Shi, Weiwei; Anderson, Mark J; Tulkoff, Joshua B; Kennedy, Brook S; Boreyko, Jonathan B

    2018-04-11

    Fog harvesting is a useful technique for obtaining fresh water in arid climates. The wire meshes currently utilized for fog harvesting suffer from dual constraints: coarse meshes cannot efficiently capture microscopic fog droplets, whereas fine meshes suffer from clogging issues. Here, we design and fabricate fog harvesters comprising an array of vertical wires, which we call "fog harps". Under controlled laboratory conditions, the fog-harvesting rates for fog harps with three different wire diameters were compared to conventional meshes of equivalent dimensions. As expected for the mesh structures, the mid-sized wires exhibited the largest fog collection rate, with a drop-off in performance for the fine or coarse meshes. In contrast, the fog-harvesting rate continually increased with decreasing wire diameter for the fog harps due to efficient droplet shedding that prevented clogging. This resulted in a 3-fold enhancement in the fog-harvesting rate for the harp design compared to an equivalent mesh.

  5. Historical harvests reduce neighboring old-growth basal area across a forest landscape.

    Science.gov (United States)

    Bell, David M; Spies, Thomas A; Pabst, Robert

    2017-07-01

    While advances in remote sensing have made stand, landscape, and regional assessments of the direct impacts of disturbance on forests quite common, the edge influence of timber harvesting on the structure of neighboring unharvested forests has not been examined extensively. In this study, we examine the impact of historical timber harvests on basal area patterns of neighboring old-growth forests to assess the magnitude and scale of harvest edge influence in a forest landscape of western Oregon, USA. We used lidar data and forest plot measurements to construct 30-m resolution live tree basal area maps in lower and middle elevation mature and old-growth forests. We assessed how edge influence on total, upper canopy, and lower canopy basal area varied across this forest landscape as a function of harvest characteristics (i.e., harvest size and age) and topographic conditions in the unharvested area. Upper canopy, lower canopy, and total basal area increased with distance from harvest edge and elevation. Forests within 75 m of harvest edges (20% of unharvested forests) had 4% to 6% less live tree basal area compared with forest interiors. An interaction between distance from harvest edge and elevation indicated that elevation altered edge influence in this landscape. We observed a positive edge influence at low elevations (800 m). Surprisingly, we found no or weak effects of harvest age (13-60 yr) and harvest area (0.2-110 ha) on surrounding unharvested forest basal area, implying that edge influence was relatively insensitive to the scale of disturbance and multi-decadal recovery processes. Our study indicates that the edge influence of past clearcutting on the structure of neighboring uncut old-growth forests is widespread and persistent. These indirect and diffuse legacies of historical timber harvests complicate forest management decision-making in old-growth forest landscapes by broadening the traditional view of stand boundaries. Furthermore, the consequences

  6. Ranking independent timber investments by alternative investment criteria

    Science.gov (United States)

    Thomas J. Mills; Gary E. Dixon

    1982-01-01

    A sample of 231 independent timber investments were ranked by internal rate of return, present net worth per acre and the benefit cost ratio—the last two discounted by 3, 6.4. 7.5. and 10 percent—to determine if the different criteria had a practical influence on timber investment ranking. The samples in this study were drawn from a group of timber investments...

  7. Study on the ventilation resistance of timbered airways (II)

    Energy Technology Data Exchange (ETDEWEB)

    Oba, S; Takiguchi, I

    1977-01-01

    From the results of a model study described in a previous paper (I), (Vol.23, No.4), a timber factor Kr is determined as a specific parameter for type of timber and as a function of spacing ratio d/e where d and e are the spacing and the height of sets respectively. A general formula for the determination of the friction coefficient of timbered airways is also proposed.

  8. Beliefs about the Potential Impacts of Exploiting Non-Timber Forest Products Predict Voluntary Participation in Monitoring

    Science.gov (United States)

    Dantas Brites, Alice; Morsello, Carla

    2017-06-01

    Harvesting and trading non-timber forest products is advocated as a win-win strategy for conservation and development, yet it can produce negative ecological and socioeconomic impacts. Hence, monitoring exploitation outcomes is essential, and participatory monitoring has been suggested to be the most suitable approach. Among possible approaches, participatory monitoring is preferred because it is likely to increase people's awareness and beliefs regarding impacts or potential impacts, thus inducing behavioral changes, although the evidence in this regard is contradictory. We therefore evaluated whether people's beliefs about the potential ecological and socioeconomic impacts of non-timber forest product exploitation increased their likelihood of volunteering to monitor. We studied a community of forest inhabitants in the Brazilian Amazon who harvested and traded a commercially important non-timber forest product. Two methods of data gathering were employed: (i) a survey of 166 adults (51 households) to evaluate people's beliefs and their stated intention to engage in four different monitoring tasks and (ii) four pilot monitoring tasks to evaluate who actually participated. Based on mixed-effects regressions, the results indicated that beliefs regarding both types of impacts could predict participation in certain tasks, although gender, age and schooling were occasionally stronger predictors. On average, people had stronger beliefs about potential socioeconomic impacts than about potential ecological impacts, with the former also predicting participation in ecological data gathering. This finding reinforces the importance of monitoring both types of impacts to help achieve the win-win outcomes originally proposed by non-timber forest product trade initiatives.

  9. Seismic retrofitting of timber framed walls

    Directory of Open Access Journals (Sweden)

    Gonçalves, A. M.

    2014-12-01

    Full Text Available After the 1755 earthquake that destroyed Lisbon, an innovative anti-seismic structural system was developed consisting of a timber skeleton, that included timber framed masonry walls. After more than 250 years these structures need rehabilitation to face the present demands. The research presented in this paper aimed at experimentally characterizing the cyclic behaviour of timber framed walls reinforced with three different methods, namely: (i elastic-plastic dampers on diagonal braces, (ii reinforcement of timber connections with steel plates, (iii application of a reinforced rendering. The elastic-plastic damper showed an unsymmetrical behaviour and some difficulties to implement in practice. The strengthening with reinforced render led to an initial stiffness increase but showed a limited deformation capacity. The walls with reinforcing steel plates at the timber connections showed the best behaviour in terms of strength, stiffness and energy dissipation.Después del terremoto de 1755 que destruyó Lisboa, un sistema estructural antisísmico muy innovador fue desarrollado. El sistema consistió en un esqueleto de madera, que incluyó la construcción de muros de mampostería con un entramado de madera. Transcurridos más de 250 años, estas estructuras necesitan rehabilitación para poder hacer frente a los requisitos estructurales actuales. La investigación presentada en este trabajo tiene como objetivo caracterizar experimentalmente el comportamiento cíclico de los muros con entramado de madera reforzados con tres métodos diferentes: (i amortiguadores elasto-plásticos, (ii refuerzo de las conexiones de madera con placas de acero, (iii aplicación de un mortero reforzado. El amortiguador elasto-plástico mostró un comportamiento asimétrico y algunas dificultades para aplicarlo en la práctica. El refuerzo con mortero reforzado condujo a un aumento de la rigidez inicial, pero reveló una capacidad de deformación limitada. Los muros con

  10. Socio-ecological costs of Amazon nut and timber production at community household forests in the Bolivian Amazon.

    Science.gov (United States)

    Soriano, Marlene; Mohren, Frits; Ascarrunz, Nataly; Dressler, Wolfram; Peña-Claros, Marielos

    2017-01-01

    The Bolivian Amazon holds a complex configuration of people and forested landscapes in which communities hold secure tenure rights over a rich ecosystem offering a range of livelihood income opportunities. A large share of this income is derived from Amazon nut (Bertholletia excelsa). Many communities also have long-standing experience with community timber management plans. However, livelihood needs and desires for better living conditions may continue to place these resources under considerable stress as income needs and opportunities intensify and diversify. We aim to identify the socioeconomic and biophysical factors determining the income from forests, husbandry, off-farm and two keystone forest products (i.e., Amazon nut and timber) in the Bolivian Amazon region. We used structural equation modelling tools to account for the complex inter-relationships between socioeconomic and biophysical factors in predicting each source of income. The potential exists to increase incomes from existing livelihood activities in ways that reduce dependency upon forest resources. For example, changes in off-farm income sources can act to increase or decrease forest incomes. Market accessibility, social, financial, and natural and physical assets determined the amount of income community households could derive from Amazon nut and timber. Factors related to community households' local ecological knowledge, such as the number of non-timber forest products harvested and the number of management practices applied to enhance Amazon nut production, defined the amount of income these households could derive from Amazon nut and timber, respectively. The (inter) relationships found among socioeconomic and biophysical factors over income shed light on ways to improve forest-dependent livelihoods in the Bolivian Amazon. We believe that our analysis could be applicable to other contexts throughout the tropics as well.

  11. 7 CFR 1437.11 - Average market price and payment factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Average market price and payment factors. 1437.11... ASSISTANCE PROGRAM General Provisions § 1437.11 Average market price and payment factors. (a) An average... average market price by the applicable payment factor (i.e., harvested, unharvested, or prevented planting...

  12. Projection of U.S. forest sector carbon sequestration under U.S. and global timber market and wood energy consumption scenarios, 2010-2060

    Science.gov (United States)

    Prakash Nepal; Peter J. Ince; Kenneth E. Skog; Sun J. Chang

    2012-01-01

    This study provides a modeling framework to examine change over time in U.S. forest sector carbon inventory (in U.S. timberland tree biomass and harvested wood products) for alternative projections of U.S. and global timber markets, including wood energy consumption, based on established IPCC/RPA scenarios. Results indicated that the U.S. forest sector’s projected...

  13. Energy wood harvesting from nurse crop of spruce seeding stand; Kuusen taimikon verhopuuston korjuu energiapuuksi

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, M.; Tanttu, V.

    2008-07-01

    The study focused on establishing the productivity and costs of mechanical energy wood cutting and the profitability of forest management alternatives in the harvesting of hold-overs from spruce seeding stands. The productivity in whole-tree harvesting performed using a multi-tree whole tree processing method reached 3.5 m3/E{sub 0}h with a felling cost of 26 euros/m3. The calculated cost of chainsaw harvesting using a felling-piling technique was 16 euros/m3. The average size of trees harvested from the research stand was 15 dm3. At a rate of 17.8 euros per megawatt that was paid for forest chips delivered to the plant, the net profit using mechanical harvesting method was 272 euros per hectare. The net profit using chainsaw harvesting was 464 euros per hectare. 'Net profit' is defined here as the total amount earned, taking into account forest management costs, the production cost of forest chips, the Kemera subsidies and the price paid for the chips at the place of usage. The net profit of felling the removed trees to the ground (not processing it into fuel) was minus 124 euros. A theoretical stumpage price rate was calculated for the energy harvesting alternatives by dividing the net result by the volume of trees harvested. Theoretical stumpage price was positive when the paid price per megawatt of chips delivered to the place of usage was 13 euros per megawatt-hour for mechanically harvested chips or 10 euros per megawatt-hour for chainsaw-harvested chips. In mechanical harvesting, 17 percent of the trees harvested were damaged in the harvesting process. While it is often essential for the forest owner to ensure that any forest management measures contribute to quick profitability, the forest management benefits that will become realisable assets in the future must nevertheless also be taken into account. (orig.)

  14. Knowledge-Based Estimation of Edible Fern Harvesting Sites in Mountainous Communities of Northeastern Japan

    Directory of Open Access Journals (Sweden)

    Toshiya Matsuura

    2013-12-01

    Full Text Available Once local expert knowledge regarding the harvesting of various non-timber forest products (NTFPs is lost, it is difficult to recover. We investigated whether the knowledge of expert forest harvesters can be used to determine the habitat distribution and harvesting sites of three popular edible wild ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous communities of western Fukushima, Japan. Using multi-criteria evaluation (MCE based on the analytic hierarchy process (AHP and geographic information system (GIS, we found that harvesters were easily able to recognize differences in the spatial characteristics of the habitat distribution of fern species due to both natural and anthropogenic factors. These factors were described by various GIS layers, such as vegetation and terrain features (e.g., gradient, aspect, and slope position derived from a 20-m digital elevation model (DEM. Harvesting sites were limited by their distance from a roadway, which differed among species. By comparison with the GPS records of actual harvesting sites, we estimated the potential harvesting sites of each fern species with reasonable accuracy, particularly for bracken. Our results show that the knowledge of expert forest harvesters can be quantified using MCE and GIS, which is useful for determining the spatial characteristics of NTFP harvesting and ensuring sustainable management practices.

  15. Maple Sugar Harvesting/Wild Rice Harvesting.

    Science.gov (United States)

    Minneapolis Public Schools, MN.

    Comprised of two separate booklets, this resource unit assists elementary teachers in explaining how the Ojibwe people harvest maple sugar and wild rice. The first booklet explains the procedure of tapping the maple trees for sap, preparation for boiling the sap, and the three forms the sugar is made into (granulated, "molded," and…

  16. Electromagnetic energy harvester for harvesting acoustic energy

    Indian Academy of Sciences (India)

    Farid U Khan

    Acoustics; energy harvesting; electromagnetic; Helmholtz resonator; sound pressure level; suspended coil. ... WSNs, which are supposed to operate for longer period of time. However ... several ambient energies such as wind, thermal, vibration, and solar are ..... textile plants in Northern India with specific reference to noise.

  17. Trade-offs between three forest ecosystem services across the state of New Hampshire, USA: timber, carbon, and albedo.

    Science.gov (United States)

    Lutz, David A; Burakowski, Elizabeth A; Murphy, Mackenzie B; Borsuk, Mark E; Niemiec, Rebecca M; Howarth, Richard B

    2016-01-01

    Forests are more frequently being managed to store and sequester carbon for the purposes of climate change mitigation. Generally, this practice involves long-term conservation of intact mature forests and/or reductions in the frequency and intensity of timber harvests. However, incorporating the influence of forest surface albedo often suggests that long rotation lengths may not always be optimal in mitigating climate change in forests characterized by frequent snowfall. To address this, we investigated trade-offs between three ecosystem services: carbon storage, albedo-related radiative forcing, and timber provisioning. We calculated optimal rotation length at 498 diverse Forest Inventory and Analysis forest sites in the state of New Hampshire, USA. We found that the mean optimal rotation lengths across all sites was 94 yr (standard deviation of sample means = 44 yr), with a large cluster of short optimal rotation lengths that were calculated at high elevations in the White Mountain National Forest. Using a regression tree approach, we found that timber growth, annual storage of carbon, and the difference between annual albedo in mature forest vs. a post-harvest landscape were the most important variables that influenced optimal rotation. Additionally, we found that the choice of a baseline albedo value for each site significantly altered the optimal rotation lengths across all sites, lowering the mean rotation to 59 yr with a high albedo baseline, and increasing the mean rotation to 112 yr given a low albedo baseline. Given these results, we suggest that utilizing temperate forests in New Hampshire for climate mitigation purposes through carbon storage and the cessation of harvest is appropriate at a site-dependent level that varies significantly across the state.

  18. Energy prices and taxes

    International Nuclear Information System (INIS)

    2004-01-01

    Energy Prices and Taxes contains a major international compilation of energy prices at all market levels: import prices, industry prices and consumer prices. The statistics cover main petroleum products, gas, coal and electricity, giving for imported products an average price both for importing country and country of origin. Every issue includes full notes on sources and methods and a description of price mechanisms in each country

  19. MARKET ECONOMICS PRICING PARTICULARS

    Directory of Open Access Journals (Sweden)

    V. I. Parshin

    2011-01-01

    Full Text Available The price performs several economic functions: accounting, stimulation, distribution, demand and offer balancing, serving as production site rational choice criterion, information. Most important pricing principles are: price scientific and purpose-aimed substantiation, single pricing and price control process. Pricing process factors are external, internal, basic (independent on money-market, market-determined and controlling. Different pricing methods and models are to be examined, recommendations on practical application of those chosen are to be written.

  20. Cost, energy use and GHG emissions for forest biomass harvesting operations

    International Nuclear Information System (INIS)

    Zhang, Fengli; Johnson, Dana M.; Wang, Jinjiang; Yu, Chunxia

    2016-01-01

    For forest-based biomass to become a significant contribution to the United States' energy portfolio, harvesting operations must be physically feasible and economically viable. An assessment of cost, energy and greenhouse gas (GHG) emissions of forest biomass harvesting was conducted. The assessment differentiates harvesting systems by cut-to-length and whole tree; harvest types of 30%, 70%, and 100% cut; and forest types of hardwoods, softwoods, mixed hardwood/softwood, and softwood plantations. Harvesting cost models were developed for economic assessment and life cycle energy and emission assessment was applied to calculate energy and emissions for different harvesting scenarios, considering material and energy inputs (machinery, diesel, etc.) and outputs (GHG emissions) for each harvesting process (felling, forwarding/skidding, etc.). The developed harvesting cost models and the life cycle energy and emission assessment method were applied in Michigan, U.S. using information collected from different sources. A sensitivity analysis was performed for selected input variables for the harvesting operations in order to explore their relative importance. The results indicated that productivity had the largest impact on harvesting cost followed by machinery purchase price, yearly scheduled hours, and expected utilization. Productivity and fuel use, as well as fuel factors, are the most influential environmental impacts of harvesting operations. - Highlights: • Life cycle energy and emissions for forest biomass harvesting operations. • Harvesting cost models were developed for economic assessment. • Productivity had the largest impact on harvesting cost. • Fuel use contributes the most emissions while lubricants contribute the least.

  1. Appropriateness of Probit-9 in development of quarantine treatments for timber and timber commodities

    Science.gov (United States)

    Marcus Schortemeyer; Ken Thomas; Robert A. Haack; Adnan Uzunovic; Kelli Hoover; Jack A. Simpson; Cheryl A. Grgurinovic

    2011-01-01

    Following the increasing international phasing out of methyl bromide for quarantine purposes, the development of alternative treatments for timber pests becomes imperative. The international accreditation of new quarantine treatments requires verification standards that give confidence in the effectiveness of a treatment. Probit-9 mortality is a standard for treatment...

  2. Wisconsin timber industry--an assessment of timber product output and use, 1988.

    Science.gov (United States)

    W. Brad Smith; James W. Whipple

    1990-01-01

    Discusses recent Wisconsin forest industry trends; production and receipts of pulpwood, saw logs, and veneer logs; and production of other timber products in 1988. Reports on logging residue, on wood and bark residue generated at primary wood-using mills, and on disposition of this mill residue.

  3. Tensile properties of machine strength graded timber for glued laminated timber

    DEFF Research Database (Denmark)

    Boström, Lars; Hoffmeyer, Preben; Solli, Kjell-Helge

    1999-01-01

    Special setting values based on tensile properties of Norway spruce are established for four different strength grading machines. The machines included are Computermatic, Cook-Bolinder, Ersson and Dynagrade.The study shows that the yield of timber to be used in tension, such as laminations...

  4. A combimachine for harvesting of small sized trees; Pienpuun keraeilykaatoon perustuvan harvennuskoneen kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Lilleberg, R [Metsaeteho, Helsinki (Finland)

    1997-12-31

    The goal of the project was to develop a combimachine suitable for the harvesting of small sized trees in first thinning. The use of such a machine could considerably decrease harvesting costs in first thinning. The basic idea with the combimachine is, that the same machine both fells the trees and transports the timber to roadside storages. A forwarder was equipped with a lightweight felling device, which also can do the crosscutting and loading. When harvesting undelimbed timber the forwarder could be equipped with a load-compressing device. During the spring 1995 a trial was made with a combimachine in a first thinning stand of pine. An ordinary forwarder was equipped with the `Naarva-grapple` a device for felling, crosscutting and loading. The aim was to test how the felling device is working, to examine time expenditure for two different working methods and to collect data for the further development of the machine. The trial showed a need to add a delimbing feature to the Naarva-grapple. The need for delimbing is based on the fact, obtained during the trial, that productivity in transport of delimbed timber was over 30 % higher than in transport of undelimbed pieces. A device capable of delimbing was designed, and it was ready for a prototype test in December 1995. The idea worked, but also showed a lot of details which have to be redesigned, before the device is ready for manufacturing and marketing

  5. A combimachine for harvesting of small sized trees; Pienpuun keraeilykaatoon perustuvan harvennuskoneen kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Lilleberg, R. [Metsaeteho, Helsinki (Finland)

    1996-12-31

    The goal of the project was to develop a combimachine suitable for the harvesting of small sized trees in first thinning. The use of such a machine could considerably decrease harvesting costs in first thinning. The basic idea with the combimachine is, that the same machine both fells the trees and transports the timber to roadside storages. A forwarder was equipped with a lightweight felling device, which also can do the crosscutting and loading. When harvesting undelimbed timber the forwarder could be equipped with a load-compressing device. During the spring 1995 a trial was made with a combimachine in a first thinning stand of pine. An ordinary forwarder was equipped with the `Naarva-grapple` a device for felling, crosscutting and loading. The aim was to test how the felling device is working, to examine time expenditure for two different working methods and to collect data for the further development of the machine. The trial showed a need to add a delimbing feature to the Naarva-grapple. The need for delimbing is based on the fact, obtained during the trial, that productivity in transport of delimbed timber was over 30 % higher than in transport of undelimbed pieces. A device capable of delimbing was designed, and it was ready for a prototype test in December 1995. The idea worked, but also showed a lot of details which have to be redesigned, before the device is ready for manufacturing and marketing

  6. Assessment of demand and supply of timber products in Benue ...

    African Journals Online (AJOL)

    This study examines demand and supply of timber products in Benue State Nigeria with a view to highlighting the responsiveness of forest policy implementation. The scope of the study lies on plantation establishment targets and costs for 1999 to 2003, actual plantation establishment, timber supply and demand from ...

  7. Field investigations of historic covered timber bridges in the USA

    Science.gov (United States)

    James Wacker; Travis Hosteng; Brent. Phares

    2012-01-01

    The Federal Highway Administration is sponsoring a comprehensive research program on Historic Covered Timber Bridges in the USA. This national program's main purpose is to develop improved methods to preserve, rehabililate, and restore the timber bridge trusses that were developed during the early 1800s, and in many cases are still in service today. The overall...

  8. The Dendrochronological Dating of Timber Crossings in West Jutland, Denmark

    DEFF Research Database (Denmark)

    Daly, Aoife

    2006-01-01

    The dendrochronological analyses of a large number of timbers from two sites are described. Nybro causeway in west Jutland, Denmark, which was built in the 8th century AD, consists of numerous phases, identifiable due to the large number of dendrochronologically dated timbers, of which many had...

  9. Influence Of Density On The Durabilities Of Three Ghanaian Timbers ...

    African Journals Online (AJOL)

    Review of factors influencing wood durability shows although density varies depending on trunk position, its role appears controversial for many timber species. Thus, for the first time, the influence of density on the durability of three Ghanaian timbers (Nauclea diderrichii (de Wild.) Merr., Nesogordonia papaverifera (A. Chev ...

  10. Lateral testing of glued laminated timber tudor arch

    Science.gov (United States)

    Douglas R. Rammer; Philip Line

    2016-01-01

    Glued laminated timber Tudor arches have been in wide use in the United States since the 1930s, but detailed knowledge related to seismic design in modern U.S. building codes is lacking. FEMA P-695 (P-695) is a methodology to determine seismic performance factors for a seismic force resisting system. A limited P-695 study for glued laminated timber arch structures...

  11. Projecting national forest inventories for the 2000 RPA timber assessment.

    Science.gov (United States)

    John R. Mills; Xiaoping. Zhou

    2003-01-01

    National forest inventories were projected in a study that was part of the 2000 USDA Forest Service Resource Planning Act (RPA) timber assessment. This paper includes an overview of the status and structure of timber inventory of the National Forest System and presents 50-year projections under several scenarios. To examine a range of possible outcomes, results are...

  12. Comparative durability of timber bridges in the USA

    Science.gov (United States)

    James P. Wacker; Brian K. Brashaw

    2017-01-01

    As engineers begin to utilize life-cycle-cost design approaches for timber bridges, there is a necessity for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This national study was...

  13. 125 Timber Dealers' Perception of their Knowledge of the Forest ...

    African Journals Online (AJOL)

    Nekky Umera

    Abstract. This study investigated timber dealers' knowledge of the forest law and regulations in Uyo Senatorial District. Five timber markets were selected through two-stage sampling. Data were collected from 238 traders in the selected markets using structured questionnaires and subjected to descriptive and inferential ...

  14. Whole tree transportation system for timber processing depots

    Science.gov (United States)

    John Lancaster; Tom Gallagher; Tim  McDonald; Dana Mitchell

    2016-01-01

    The growing demand for alternative energy has led those who are interested in producing sustainable energy from renewable timber to devise new concepts to satisfy those demands. The concept of timber processing depots, where whole stem trees will be delivered for future processing into wood products and high quality energy fuel, has led to the re-evaluation of our...

  15. Infill Panels and the tube connection in timber frames

    NARCIS (Netherlands)

    Leijten, A.J.M.; Jorissen, A.J.M.; Hoenderkamp, J.C.D.

    2012-01-01

    In recent years timber infill panels have been proposed for multi-story column-beam frame structures with the aim to substitute the stabilizing function of column-beam moment connections. The preliminary study reported in this paper considers a column-beam timber frame where stability is assured by

  16. Lateral Stiffness of Timber Frames with CLT Infill Panels

    NARCIS (Netherlands)

    Leijten, A.J.M.; Jorissen, A.J.M.; Hoenderkamp, J.C.D.; Haddad, Y.M.

    2011-01-01

    In recent years timber infill panels have been proposed for multi-story column-beam frame structures with the aim to substitute the stabilizing function of column-beam moment connections. The preliminary study reported in this paper considers a column-beam timber frame where stability is assured by

  17. Feasibility Investigation into Strengthening of Timber Bridge Stringers

    Science.gov (United States)

    2007-05-01

    12 Studies on timber members recycled from old timber structures...55 Figure 63. The load cell-hydraulic ram setup with spreader beam.....................................................56 Figure 64. The MTS...actuator and spreader beam................................................................................56 Figure 65. Effectiveness of a repair method

  18. Company-Community Logging Contracts in Amazonian Settlements: Impacts on Livelihoods and NTFP Harvests

    Directory of Open Access Journals (Sweden)

    Mary C. S. Menton

    2009-06-01

    Full Text Available As a result of government-sponsored colonization, more than 500 000 km2 of the Brazilian Amazon is managed by settlement households. By law, 80% of this land must remain as standing forest. In this study, we examine the potential for timber harvesting through company-community partnerships (CCPs as a means to increase forest-based revenue without compromising household use of non-timber forest products (NTFPs. Using participatory rural appraisal, resource diaries, and household questionnaires, we study the impacts of CCP logging contracts on livelihoods, including household income and NTFP harvests. Our results show that annual household income from the CCP logging is equivalent to more than 8 years of household gross income from agricultural production. We also found that there were no significant differences in NTFP harvests between households with CCP logging and those without. In CCP-logging communities, households caught 11.9 ± 13.6 game animals, totaling 74 ± 88 kg of game meat. In the communities without CCP, households caught 9.5 ± 13.0 game animals, totaling 73 ± 172 kg of game meat. Annual forest fruit harvests averaged 9.8 ± 13.2 kg in CCP-logging communities and 13.5 ± 15.9 kg in non-CCP communities. Overall, the CCPs brought improvements in household income without compromising NTFP harvests.

  19. Bundling harvester; Nippukorjausharvesteri

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, K. [Eko-Log Oy, Kuopio (Finland)

    1996-12-31

    The staring point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automatizing of the harvester, and automatized loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilization of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilized without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilization of wood-energy

  20. Bundling harvester; Nippukorjausharvesteri

    Energy Technology Data Exchange (ETDEWEB)

    Koponen, K [Eko-Log Oy, Kuopio (Finland)

    1997-12-31

    The staring point of the project was to design and construct, by taking the silvicultural point of view into account, a harvesting and processing system especially for energy-wood, containing manually driven bundling harvester, automatizing of the harvester, and automatized loading. The equipment forms an ideal method for entrepreneur`s-line harvesting. The target is to apply the system also for owner`s-line harvesting. The profitability of the system promotes the utilization of the system in both cases. The objectives of the project were: to construct a test equipment and prototypes for all the project stages, to carry out terrain and strain tests in order to examine the usability and durability, as well as the capacity of the machine, to test the applicability of the Eko-Log system in simultaneous harvesting of energy and pulp woods, and to start the marketing and manufacturing of the products. The basic problems of the construction of the bundling harvester have been solved using terrain-tests. The prototype machine has been shown to be operable. Loading of the bundles to form sufficiently economically transportable loads has been studied, and simultaneously, the branch-biomass has been tried to be utilized without loosing the profitability of transportation. The results have been promising, and will promote the profitable utilization of wood-energy

  1. RILEM International Symposium on Materials and Joints in Timber Structures

    CERN Document Server

    Reinhardt, H-W; Garrecht, Harald

    2014-01-01

    This book contains the contributions from the RILEM International Symposium on Materials and Joints in Timber Structures that was held in Stuttgart, Germany from October 8 to 10, 2013. It covers recent developments in the materials and the joints used in modern timber structures. Regarding basic wooden materials, the contributions highlight the widened spectrum of products comprising cross-laminated timber, glulam and LVL from hardwoods and block glued elements. Timber concrete compounds, cement bonded wood composites and innovative light-weight constructions represent increasingly employed alternatives for floors, bridges and facades. With regard to jointing technologies, considerable advances in both mechanical connections and glued joints are presented. Self-tapping screws have created unprecedented options for reliable, strong as well as ductile joints and reinforcement technologies. Regarding adhesives, which constitute the basis of the jointing/laminating technology of modern timber products, extended o...

  2. On several parameters of mechanized timbering for working faces

    Energy Technology Data Exchange (ETDEWEB)

    Klorik' yan, S Kh

    1979-08-01

    Opinion is expressed that the two basic parameters characterizing mechanical timbers, the specific force in ton-forces per square meter of the supported roof surface over the working area and the one-meter length of installed timbering, do not permit selection of the optimum type of timber for a roof of the corresponding class. Experience has demonstrated that the most precise parameter is specific strength of the timber in ton-forces per meter and the determined ratio of the strength of all posts in a section to spacing of the section along the longwall. Also an operating width not exceeding 0.4 meter should serve as a criterion for using timbers on unstable hanging walls. (In Russian)

  3. Durability of timber silencers at Wairakei geothermal steam field

    Energy Technology Data Exchange (ETDEWEB)

    Hedley, M E

    1979-02-01

    After early failures of reinforced concrete silencers and because of high costs of concrete-lined steel structures, preliminary tests were undertaken to assess the suitability of timber for silencer construction. Tests indicated that radiata pine treated with pentachlorophenol/oil or untreated red beech had most potential for timber silencer fabrication. One prototype silencer of each material was constructed and both were installed on operational bores in 1965. The red beech silencer had a service life of 4 years. The radiata pine silencer operated for 12/sup 1///sub 2/ years, although replacement had been recommended 1 year before this time expired. The performance of this silencer encouraged the general use of timber for silencer construction and further units were built. Procurement of satisfactory grades of timber has proved difficult and has limited silencer fabrication. Ways of improving timber supply, which require modification of silencer design, are discussed.

  4. Legal harvesting, sustainable sourcing and cascaded use of wood for bioenergy : Their coverage through existing certification frameworks for sustainable forest management

    NARCIS (Netherlands)

    Sikkema, Richard; Junginger, Martin; van Dam, Jinke; Stegeman, Gerben; Durrant, David; Faaij, Andre

    2014-01-01

    The first objective of this paper was to provide an inventory of developments of certification schemes for sustainable biomass production, following recent EU legislation (both formalized and under development). One main pillar is the EU Timber Regulation for legal harvesting; a second one is the

  5. Moisture Content Monitoring of a Timber Footbridge

    Directory of Open Access Journals (Sweden)

    Niclas Björngrim

    2016-03-01

    Full Text Available Construction of modern timber bridges has greatly increased during the last 20 years in Sweden. Wood as a construction material has several advantageous properties, e.g., it is renewable, sustainable, and aesthetically pleasing, but it is also susceptible to deterioration. To protect wood from deterioration and ensure the service life, the wood is either treated or somehow covered. This work evaluates a technology to monitor the moisture content in wood constructions. Monitoring the moisture content is important both to verify the constructive protection and for finding areas with elevated levels of moisture which might lead to a microbiological attack of the wood. In this work, a timber bridge was studied. The structure was equipped with six wireless sensors that measured the moisture content of the wood and the relative humidity every hour. Data for 744 days of the bridge are presented in this paper. Results show that the technology used to monitor the bridge generally works; however, there were issues due to communication problems and malfunction of sensors. This technology is promising for monitoring the state of wood constructions, but a more reliable sensor technology is warranted continuous remote monitoring of wood bridges over long periods of time.

  6. Energy harvesting for microsystems

    DEFF Research Database (Denmark)

    Xu, Ruichao

    The purpose of this project is to design and fabricate piezoelectric energy harvesters based on integration of Pb(ZrxTi1-x)O3 (PZT) thick film technology and silicon microtechnology. The fabrication processes are carried out in close collaboration with Meggitt Sensing Systems (MSS) who has...... the unique expertise to screen print piezoelectric thick film layers, thus all screen printing steps are done by MSS while the silicon micromachining is carried out at Danchip facility at DTU. The presented energy harvesters are all based on using piezoelectric thick film operating in the 31-mode to generate...... power when strained. Three archetypes of the numerous fabricated energy harvesters will be presented in detail, they represent three major milestones in this project. The first energy harvester archetype has an unimorph cantilever beam, which consists of a 20 µm silicon layer and 10-30 µm screen printed...

  7. African Urban Harvest

    International Development Research Centre (IDRC) Digital Library (Canada)

    Urban Harvest, a system-wide initiative of the Consultative Group on Agricultural ...... and urban old, using criteria of population density, land availability, and the prevalence of crop ...... Contact between milk and containers or the environment;.

  8. Energy harvesting water vehicle

    KAUST Repository

    Singh, Devendra

    2018-01-01

    An efficient energy harvesting (EEH) water vehicle is disclosed. The base of the EEH water vehicle is fabricated with rolling cylindrical drums that can rotate freely in the same direction of the water medium. The drums reduce the drag

  9. Conceptual framework for Non-Timber Forest Products in mangroves of Colombia

    International Nuclear Information System (INIS)

    Garcia S, Catalina; Polania V, Jaime

    2008-01-01

    The forests policy of most of tropical countries is directed initially toward the use of Wood resources and, secondarily, for firewood. Nevertheless, tropical forests generate other products that, in some countries, can have a high value, comparable with those of wood, called 'Non Timber Forest Products' (NTFP) or 'Non Wood Forest Products' (NWFP). Unfortunately this label does not enhance the fact that its harvest is an important activity in rural economies. The NTFP have motivated interest by their economic and social contribution in many countries, mainly for rural populations? all along Latin America are utilized, and, particularly in Colombia, it is necessary to regulate clearly and accurately their exploitation. Here we present a conceptual framework for the NTFP's, and describe the potential contribution of mangroves to this market in Colombia

  10. Economic valuation of subsistence harvest of wildlife in Madagascar.

    Science.gov (United States)

    Golden, Christopher D; Bonds, Matthew H; Brashares, Justin S; Rasolofoniaina, B J Rodolph; Kremen, Claire

    2014-02-01

    Wildlife consumption can be viewed as an ecosystem provisioning service (the production of a material good through ecological functioning) because of wildlife's ability to persist under sustainable levels of harvest. We used the case of wildlife harvest and consumption in northeastern Madagascar to identify the distribution of these services to local households and communities to further our understanding of local reliance on natural resources. We inferred these benefits from demand curves built with data on wildlife sales transactions. On average, the value of wildlife provisioning represented 57% of annual household cash income in local communities from the Makira Natural Park and Masoala National Park, and harvested areas produced an economic return of U.S.$0.42 ha(-1) · year(-1). Variability in value of harvested wildlife was high among communities and households with an approximate 2 orders of magnitude difference in the proportional value of wildlife to household income. The imputed price of harvested wildlife and its consumption were strongly associated (p< 0.001), and increases in price led to reduced harvest for consumption. Heightened monitoring and enforcement of hunting could increase the costs of harvesting and thus elevate the price and reduce consumption of wildlife. Increased enforcement would therefore be beneficial to biodiversity conservation but could limit local people's food supply. Specifically, our results provide an estimate of the cost of offsetting economic losses to local populations from the enforcement of conservation policies. By explicitly estimating the welfare effects of consumed wildlife, our results may inform targeted interventions by public health and development specialists as they allocate sparse funds to support regions, households, or individuals most vulnerable to changes in access to wildlife. © 2013 Society for Conservation Biology.

  11. Pricing and Trust

    DEFF Research Database (Denmark)

    Huck, Steffen; Ruchala, Gabriele K.; Tyran, Jean-Robert

    -competitive (monopolistic) markets. We then introduce a regulated intermediate price above the oligopoly price and below the monopoly price. The effect in monopolies is more or less in line with standard intuition. As price falls volume increases and so does quality, such that overall efficiency is raised by 50%. However......We experimentally examine the effects of flexible and fixed prices in markets for experience goods in which demand is driven by trust. With flexible prices, we observe low prices and high quality in competitive (oligopolistic) markets, and high prices coupled with low quality in non...

  12. Efeito do tempo de experiência de operadores de Harvester no rendimento operacional Effect of time experience of Harvester operators in operating yield

    Directory of Open Access Journals (Sweden)

    Elaine Cristina Leonello

    2012-12-01

    Full Text Available A mecanização da colheita de madeira permite maior controle dos custos e pode proporcionar reduções em prazos relativamente curtos. Além disso, tem um lugar de destaque na humanização do trabalho florestal e no aumento do rendimento operacional. O presente trabalho teve por objetivo avaliar o desempenho de operadores de harvester em função do tempo de experiência na atividade. Foram avaliados oito operadores do sexo masculino, com idade entre 23 e 46 anos. O estudo consistiu na análise do volume de madeira colhida pelo harvester. O tempo de experiência afeta significativamente o rendimento operacional dos operadores de harvester. Tal rendimento aumenta expressivamente nos primeiros 18 meses de experiência, mantendo-se em ascensão nos próximos 26 meses. Após os 44 meses de experiência, o rendimento dos operadores tende a reduzir, revelando as possíveis acomodações do cotidiano. Tais resultados permitem concluir que por volta dos 50 meses de experiência na atividade de operação de harvester, se faz necessária a adoção de medidas de reciclagem, motivação, entre outras, a fim de proporcionar aos operadores melhores condições de trabalho que os possibilitem continuar exercendo a atividade de forma eficiente e rentável à empresa.The mechanization of timber harvesting allows greater control of costs and can provide reductions in relatively short intervals. Moreover, it has a place in the humanization of the working forest and the increase in performance. This work provides comparisons of operating performance of different operator harvester according to the time of experience in the activity. The operators evaluated were eight males, aged between 23 and 46 years old. The study consisted of analysis of the volume of timber harvested by the harvester. The experience significantly affects the performance of harvesters operators. The performance increases significantly in the first 18 months of experience, and it remained on

  13. 7 CFR 1000.50 - Class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Class prices, component prices, and advanced pricing... advanced pricing factors. Class prices per hundredweight of milk containing 3.5 percent butterfat, component prices, and advanced pricing factors shall be as follows. The prices and pricing factors described...

  14. Food Prices and Climate Extremes: A Model of Global Grain Price Variability with Storage

    Science.gov (United States)

    Otto, C.; Schewe, J.; Frieler, K.

    2015-12-01

    Extreme climate events such as droughts, floods, or heat waves affect agricultural production in major cropping regions and therefore impact the world market prices of staple crops. In the last decade, crop prices exhibited two very prominent price peaks in 2007-2008 and 2010-2011, threatening food security especially for poorer countries that are net importers of grain. There is evidence that these spikes in grain prices were at least partly triggered by actual supply shortages and the expectation of bad harvests. However, the response of the market to supply shocks is nonlinear and depends on complex and interlinked processes such as warehousing, speculation, and trade policies. Quantifying the contributions of such different factors to short-term price variability remains difficult, not least because many existing models ignore the role of storage which becomes important on short timescales. This in turn impedes the assessment of future climate change impacts on food prices. Here, we present a simple model of annual world grain prices that integrates grain stocks into the supply and demand functions. This firstly allows us to model explicitly the effect of storage strategies on world market price, and thus, for the first time, to quantify the potential contribution of trade policies to price variability in a simple global framework. Driven only by reported production and by long--term demand trends of the past ca. 40 years, the model reproduces observed variations in both the global storage volume and price of wheat. We demonstrate how recent price peaks can be reproduced by accounting for documented changes in storage strategies and trade policies, contrasting and complementing previous explanations based on different mechanisms such as speculation. Secondly, we show how the integration of storage allows long-term projections of grain price variability under climate change, based on existing crop yield scenarios.

  15. Competitive Pricing by a Price Leader

    OpenAIRE

    Abhik Roy; Dominique M. Hanssens; Jagmohan S. Raju

    1994-01-01

    We examine the problem of pricing in a market where one brand acts as a price leader. We develop a procedure to estimate a leader's price rule, which is optimal given a sales target objective, and allows for the inclusion of demand forecasts. We illustrate our estimation procedure by calibrating this optimal price rule for both the leader and the follower using data on past sales and prices from the mid-size sedan segment of the U.S. automobile market. Our results suggest that a leader-follow...

  16. ACCOUNTING ASPECTS OF PRICING AND TRANSFER PRICING

    Directory of Open Access Journals (Sweden)

    TÜNDE VERES

    2011-01-01

    Full Text Available The pricing methods in practice need really complex view of the business situation and depend on the strategy and market position of a company. The structure of a price seems simple: cost plus margin. Both categories are special area in the management accounting. Information about the product costs, the allocation methodologies in cost accounting, the analyzing of revenue and different level of the margin needs information from accounting system. This paper analyzes the pricing methods from management accounting aspects to show out the role of the accounting system in the short term and long term pricing and transfer pricing decisions.

  17. System Reliability of Timber Structures with Ductile Behaviour

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Čizmar, Dean

    2011-01-01

    The present paper considers the evaluation of timber structures with the focus on robustness due to connection ductility. The robustness analysis is based on the structural reliability framework applied to a simplified mechanical system. The structural timber system is depicted as a parallel system....... An evaluation method of the ductile behaviour is introduced. For different ductile behaviours, the system reliability is estimated based on Monte Carlo simulation. A correlation between the strength of the structural elements is introduced. The results indicate that the reliability of a structural timber system...

  18. Robustness Issues for Design of Innovative Timber Structures

    DEFF Research Database (Denmark)

    Hald, Frederik; Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2013-01-01

    Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious conse-quences in case of failure. The present paper summaries issues with respect to robustness of timber structures. Two different...... large span timber structures are analyzed and based on these analyses the paper presents guidelines for the future development of innovative timber struc-tures which are robust with respect to design and execution errors, unforeseen degradation and other potential hazards....

  19. Moment Capacity of Timber Reinforced with Punched Metal Plate Fasteners

    DEFF Research Database (Denmark)

    Nielsen, Jacob; Ellegaard, Peter

    When designing timber trusses it is often found that the cross section controlling the dimensions of the top chord is located at a joint with a moment peak. However, the timber volume affected by the moment peak is rather limited and by embedding a punched metal plate in this area a reinforcement...... of the section is obtained, resulting in a more economic truss design. In order to develop design methods for sections with plate reinforcement, bending tests have been made. The timber is Swedish spruce of strength class K-18(S8) and K-24(S10) with a thickness of 45 mm. The punched metal plate is from Gang...

  20. Small timber harvesting on slopes using the small winch and modified Goldberg methods

    Energy Technology Data Exchange (ETDEWEB)

    Fritzsche, W; Sagowski, H

    1981-01-01

    Results are summarized of work studies in 1980 during thinnings in 50- to 60-yr-old beech stands in Forest District Rinteln (Lower Saxony) involving: (a) one-man working using a chain saw and a NORDFOR small (0.8 t) winch to skid 1-2 logs (4-6 m long) to skidding lane, followed by forwarder transport; or (b) 2-man working (in rotation) using a chain saw and a 65 hp tractor/Schlang and Reichart double-drum winch combination to skid 8-15 trimmed tree lengths to goods road or stacking area. Average log volume (cubic m) was 0.18 (a), 0.24 (b); skidding distance (m) was 200-400 (a), average 110 (b). Performance was superior in (b), even in the optimal log volume range of (a), especially at skidding distances less than 200 m. Costs in (a) were 45 DM/0.18 cubic m, in (b) 30DM/0.25 cubic m. Work performance standards and wage calculation factors are given. In both methods, net profit (average 20 DM/cubic 3) was greater and damage to main crop (less than 5%) was lower than for preparation of long industrial wood using the conventional HET/EST wage rate systems. (Refs. 2).

  1. Changes in vegetative communities and water table dynamics following timber harvesting in small headwater streams

    Science.gov (United States)

    B. Choi; J.C. Dewey; J. A. Hatten; A.W. Ezell; Z. Fan

    2012-01-01

    In order to better understand the relationship between vegetation communities and water table in the uppermost portions (ephemeral–intermittent streams) of headwater systems, seasonal plot-based field characterizations of vegetation were used in conjunction with monthly water table measurements. Vegetation, soils, and water table data were examined to determine...

  2. Heterogeneity and option pricing

    NARCIS (Netherlands)

    Benninga, Simon; Mayshar, Joram

    2000-01-01

    An economy with agents having constant yet heterogeneous degrees of relative risk aversion prices assets as though there were a single decreasing relative risk aversion pricing representative agent. The pricing kernel has fat tails and option prices do not conform to the Black-Scholes formula.

  3. Midcycle evaluation of Mississippi timber resources

    Science.gov (United States)

    Dwane D. Van Hooser

    1973-01-01

    Between 1967 and 1972 forest acreage in Mississippi decreased by 1 percent, but softwood volume increased by 10 percent and hardwood by 6 percent. More than 0.5 billion cubic feet of roundwood were harvested from the State's forests in 1972.

  4. Regulation of Pharmaceutical Prices

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Mendez, Susan J.; Rønde, Thomas

    On April 1, 2005, Denmark changed the way references prices, a main determinant of reimbursements for pharmaceutical purchases, are calculated. The previous reference prices, which were based on average EU prices, were substituted to minimum domestic prices. Novel to the literature, we estimate...... the joint eects of this reform on prices and quantities. Prices decreased more than 26 percent due to the reform, which reduced patient and government expenditures by 3.0 percent and 5.6 percent, respectively, and producer revenues by 5.0 percent. The prices of expensive products decreased more than...

  5. Water harvest via dewing.

    Science.gov (United States)

    Lee, Anna; Moon, Myoung-Woon; Lim, Hyuneui; Kim, Wan-Doo; Kim, Ho-Young

    2012-07-10

    Harvesting water from humid air via dewing can provide a viable solution to a water shortage problem where liquid-phase water is not available. Here we experimentally quantify the effects of wettability and geometry of the condensation substrate on the water harvest efficiency. Uniformly hydrophilic surfaces are found to exhibit higher rates of water condensation and collection than surfaces with lower wettability. This is in contrast to a fog basking method where the most efficient surface consists of hydrophilic islands surrounded by hydrophobic background. A thin drainage path in the lower portion of the condensation substrate is revealed to greatly enhance the water collection efficiency. The optimal surface conditions found in this work can be used to design a practical device that harvests water as its biological counterpart, a green tree frog, Litoria caerulea , does during the dry season in tropical northern Australia.

  6. epidemiology of eye diseases among timber workers in owerri

    African Journals Online (AJOL)

    LIVINGSTON

    pinguecula and uveitis, each, accounting for 39.52%, 31.10%, 12.53%, 7.34% and 2.16% respectively ... Timber workers, eye diseases, work environment, prevalence, environmental pollutants. ... there was no interested family member to take.

  7. Profitability of Clerodendrum volubile (eweta) , a non-timber forest ...

    African Journals Online (AJOL)

    Timber Forest product, in Okitipupa, Ondo State Nigeria. Purposive and simple random sampling techniques were used in the selection of markets and respondents. The sample size was 60 and instrument of data collection was structured and ...

  8. Community Based Ecological Monitoring of Non Timber Forest ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Community Based Ecological Monitoring of Non Timber Forest Products in the Nilgiri ... This project will allow Keystone Foundation to design, implement and test a ... traders, forest department officials and other stakeholders in the process.

  9. Creosote treated timber in the Alaskan marine environment : Volume I.

    Science.gov (United States)

    2010-02-01

    ADOT&PF is responsible for many structures that incorporate wood pilings and other timber in Alaska waters. Most are treated with preservative to inhibit marine borers : that will quickly destroy unprotected wood. Creosote is generally the most econo...

  10. Minimizing corrosive action in timber bridges treated with waterborne preservatives

    Science.gov (United States)

    Samuel L. Zelinka; Douglas R. Rammer; James P. Wacker

    2007-01-01

    This work will briefly review published literature and current research activities on the corrosion of metals in contact with wood treated with waterborne alternatives to CCA. In addition, recommendations to minimize these corrosive effects in timber bridges will be discussed.

  11. Impact of timber production and transport costs on stand management

    Science.gov (United States)

    Chris B. LeDoux; Chris B. LeDoux

    1988-01-01

    Evaluates the impact of cable logging technology, transportation network standards, and transport vehicles on stand management. Managers can use results to understand the impact of timber production costs on eastern hardwood management.

  12. Compression strength perpendicular to grain of structural timber and glulam

    DEFF Research Database (Denmark)

    Damkilde, Lars; Hoffmeyer, Preben; Pedersen, Torben N.

    1998-01-01

    The characteristic strength values for compression perpendicular to grain as they appear in EN 338 (structural timber) and EN 1194 (glulam) are currently up for discussion. The present paper provides experimental results based on EN 1193 that may assist in the correct assignment of such strength...... values. The dominant failure mode of glulam specimens is shown to be fundamentally different from that of structural timber specimens. Glulam specimens often show tension perpendicular to grain failure before the compression strength value is reached. Such failure mode is not seen for structural timber....... Nonetheless test results show that the levels of characteristic compression strength perpendicular to grain are of the same order for structural timber and glulam. The values are slightly lower than those appearing in EN 1194 and less than half of those appearing in EN 338. The paper presents a numerical...

  13. Modeling the Effects of Knots in Structural Timber

    DEFF Research Database (Denmark)

    Foley, Christina

    The main purpose of the pursued research presented in this thesis is to increase knowledge of the effects of knots in structural timber so that characteristics of weaker timber may be determined and applied to improve current grading techniques. In the process, a three-dimensional fiber paradigm...... are given to Shigo's knot formation theory, and thus predicts two separate patterns of fiber direction within annual growth layers related to live knots. In order to determine the possibility to practically and non destructively predict local material directions in structural timber with the three...... was established, which describes variations of radial growth direction and fiber orientation related to knots in timber. The adaptability of the paradigm allows practically any softwood knot and its effect on surrounding wood material to be modeled with an accuracy that is limited only by input data. The knot...

  14. Probabilistic representation of duration of load effects in timber structures

    DEFF Research Database (Denmark)

    Svensson, Staffan

    2011-01-01

    Reliability analysis of structures for the purpose of code calibration or reliability verification of specific structures requires that the relevant failure modes are represented and analyzed. For structural timber, sustaining a life load, two failure cases for each failure mode have......-based design of timber structures in terms of a modification factor View the MathML source which is multiplied on the short-term resistance of the timber material. The scenario of a beam subject to office space life loads is analyzed and the modification factor View the MathML source is calibrated by using...... to be considered. These two cases are maximum load level exceeding load-carrying capacity and damage accumulation (caused by the load and its duration) leading to failure. The effect of both load intensity and load duration on the capacity of timber has been an area of large interest over the last decades...

  15. 26 CFR 1.611-3 - Rules applicable to timber.

    Science.gov (United States)

    2010-04-01

    ..., the total quantity under consideration, and the location of the timber in question with reference to... or shares, royalties and rentals, valuation for local or State taxation, partnership accountings...

  16. structural reliability of the nigerian grown abura timber bridge beam

    African Journals Online (AJOL)

    ENGR. J. I. AGUWA

    2013-07-02

    Jul 2, 2013 ... Structural analysis and deterministic design of a timber bridge beam using the Nigerian ... practice especially when it involves naturally occuring materials .... the beam due to distributed loads is; from [15]. (4). It is assumed that ...

  17. Influence of Compression Stresses on Timber Potentials of ...

    African Journals Online (AJOL)

    Eucalyptus camaldulensis Denhn in North-Western Nigeria. *1A. ... further research should be carried out on wood in service to study the peculiarities of timber behaviour under actual .... eastern Nigeria, Neem (Azadirachta indica) was found.

  18. Assessing Bioenergy Harvest Risks: Geospatially Explicit Tools for Maintaining Soil Productivity in Western US Forests

    Directory of Open Access Journals (Sweden)

    Deborah Page-Dumroese

    2011-09-01

    Full Text Available Biomass harvesting for energy production and forest health can impact the soil resource by altering inherent chemical, physical and biological properties. These impacts raise concern about damaging sensitive forest soils, even with the prospect of maintaining vigorous forest growth through biomass harvesting operations. Current forest biomass harvesting research concurs that harvest impacts to the soil resource are region- and site-specific, although generalized knowledge from decades of research can be incorporated into management activities. Based upon the most current forest harvesting research, we compiled information on harvest activities that decrease, maintain or increase soil-site productivity. We then developed a soil chemical and physical property risk assessment within a geographic information system for a timber producing region within the Northern Rocky Mountain ecoregion. Digital soil and geology databases were used to construct geospatially explicit best management practices to maintain or enhance soil-site productivity. The proposed risk assessments could aid in identifying resilient soils for forest land managers considering biomass operations, policy makers contemplating expansion of biomass harvesting and investors deliberating where to locate bioenergy conversion facilities.

  19. One TV, One Price?

    OpenAIRE

    Jean Imbs; Haroon Mumtaz; Morten O. Ravn; Hélène Rey

    2009-01-01

    We use a unique dataset on television prices across European countries and regions to investigate the sources of differences in price levels. Our findings are as follows: (i) Quality is a crucial determinant of price differences. Even in an integrated economic zone as Europe, rich economies tend to consume higher quality goods. This effect accounts for the lion’s share of international price dispersion. (ii) Sizable international price differentials subsist even for the same television sets. ...

  20. Value-based pricing

    OpenAIRE

    Netseva-Porcheva Tatyana

    2010-01-01

    The main aim of the paper is to present the value-based pricing. Therefore, the comparison between two approaches of pricing is made - cost-based pricing and value-based pricing. The 'Price sensitively meter' is presented. The other topic of the paper is the perceived value - meaning of the perceived value, the components of perceived value, the determination of perceived value and the increasing of perceived value. In addition, the best company strategies in matrix 'value-cost' are outlined. .

  1. Energy harvesting for microsystems

    Energy Technology Data Exchange (ETDEWEB)

    Ruichao Xu

    2012-05-15

    The purpose of this project is to design and fabricate piezoelectric energy harvesters based on integration of Pb(ZrxTi1-x)O3 (PZT) thick film technology and silicon microtechnology. The fabrication processes are carried out in close collaboration with Meggitt Sensing Systems (MSS) who has the unique expertise to screen print piezoelectric thick film layers, thus all screen printing steps are done by MSS while the silicon micromachining is carried out at Danchip facility at DTU. The presented energy harvesters are all based on using piezoelectric thick film operating in the 31-mode to generate power when strained. Three archetypes of the numerous fabricated energy harvesters will be presented in detail, they represent three major milestones in this project. The first energy harvester archetype has an unimorph cantilever beam, which consists of a 20 {mu}m silicon layer and 10-30 {mu}m screen printed PZT layer, anchored on a silicon frame at one end and attached to a silicon proof mass at the other. Electrodes will cover both side of the PZT layer, so the harvested energy can be collected electrically. The second archetype has a bimorph cantilever beam, which consists of two 15-35 {mu}m PZT layers, anchored on a silicon frame at the one end and attached to a silicon proof mass at the other. Electrodes are deposited below, between and above the two PZT layers. The root mean square (RMS) power output measured on this type of harvesters is as high as 37.1{mu}W at 1 g. The third archetype is similar to the first one, the screen printed PZT layer is replaced by a lead free piezoelectric material, (KxNa1-x)NbO3 (KNN). Some of the major challenges encountered during the development processes are bad adhesion, fragile structures and short circuiting through the PZT layer. All of which have being fully or partially solved in this project. The final energy harvesters are designed to be used in an energy harvester powered wireless sensing system. (Author)

  2. Timber resource statistics for the Yakataga inventory unit, Alaska, 1976.

    Science.gov (United States)

    Willem W.S. van Hees

    1985-01-01

    Statistics on forest area, total gross and net timber volumes, and annual net growth and mortality are presented from the 1976 timber inventory of the Yakataga unit, Alaska. Timberland area is estimated at 209.3 thousand acres (84.7 thousand ha), net growing stock volume at 917.1 million cubic feet (26.0 million m3), and annual net growth and...

  3. Dowelled structural connections in laminated bamboo and timber

    OpenAIRE

    Reynolds, Thomas Peter; Sharma, Bhavna; Harries, Kent; Ramage, Michael Hector

    2015-01-01

    Structural sections of laminated bamboo can be connected using methods common in timber engineering, however the different material properties of timber and laminated bamboo suggest that the behaviour of connections in the two materials would not be the same. This study investigates the dowelled connection, in which a connector is passed through a hole in the material, and load is resisted by shear in the connector and embedment into the surrounding material. Steel dowels were used in a conne...

  4. T-section glulam timber bridge modules : modeling and performance

    Science.gov (United States)

    Paul A. Morgan; Steven E. Taylor; Michael A. Ritter; John M. Franklin

    1999-01-01

    This paper describes the design, modeling, and testing of two portable timber bridges, each consisting of two noninterconnected longitudinal glued-laminated timber (glulam) deck panels 1.8 m (6 ft) wide. One bridge is 12.2 m (40 ft) long while the other bridge is 10.7 m (35 ft) long. The deck panels are fabricated in a unique double-tee cross section. The bridges...

  5. Reliability based Robustness of Timber Structures through NDT Data Updating

    DEFF Research Database (Denmark)

    Sousa, Hélder S.; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    2011-01-01

    This work presents a framework for reliability-based assessment of timber structures / members using data gathered from non-destructive test results. These results are used for modeling an update of the mechanical characteristics of timber, using Bayesian methods. Results gathered from ultrasound...... of the structure, thus, being possible to evaluate reliability based in time dependent factors, as well to categorize that structure in terms of robustness. For exemplification of the underlined concepts, three different types of structures are studied....

  6. Parametric Evaluation of Racking Performance of Platform Timber Framed Walls

    OpenAIRE

    Dhonju, R..; D’Amico, B..; Kermani, A..; Porteous, J..; Zhang, B..

    2017-01-01

    This paper provides a quantitative assessment of the racking performance of partially anchored timber framed walls, based on experimental tests. A total of 17 timber framed wall specimens, constructed from a combination of materials under different load configurations, were tested. The experimental study was designed toexamine the influence of a range of geometrical parameters, such as fastener size and spacings, wall length, arrangement of studs and horizontal members, as well as the effect ...

  7. ACCOUNTING ASPECTS OF PRICING AND TRANSFER PRICING

    OpenAIRE

    TÜNDE VERES

    2011-01-01

    The pricing methods in practice need really complex view of the business situation and depend on the strategy and market position of a company. The structure of a price seems simple: cost plus margin. Both categories are special area in the management accounting. Information about the product costs, the allocation methodologies in cost accounting, the analyzing of revenue and different level of the margin needs information from accounting system. This paper analyzes the pricing methods from m...

  8. Section of mechanized timbering of an installation layer

    Energy Technology Data Exchange (ETDEWEB)

    Gur' yev, D K; Tomashevskiy, L P; Vorotnyak, M V

    1980-07-28

    A section of mechanized timbering of an installation layer is suggested which includes roof timber, base with cantilever, hydrostand, safety guard which consists of a lower and upper shield, where the lower shield in the lower part has a roll whose upper part is hinged to the cantilever base, and the upper shield is hinged to the roof timber. Its lower part is connected by a linkage to the cantilever of the base. There is also a correcting device, tie rod and holder with rolled material. In order to guarantee stability of the timbering section during work on thick beds and adaptability of the roof timber to the roofing of the bed, the connection between the cantilever and the lower part of the upper shield is made from a longitudinal slit on the cantilever and slide bar placed in it. It is attached by a pin to the lower part of the upper shield. In this case the tie bar is hinged to the linkage and by means of the slide bar to the roof timber, while the correcting device is made of an extension-type support with level which contacts with the wedge and the tightening element installed on the cantilever of the base.

  9. Estimating Soil Displacement from Timber Extraction Trails in Steep Terrain: Application of an Unmanned Aircraft for 3D Modelling

    Directory of Open Access Journals (Sweden)

    Marek Pierzchała

    2014-06-01

    Full Text Available Skid trails constructed for timber extraction in steep terrain constitute a serious environmental concern if not well planned, executed and ameliorated. Carrying out post-harvest surveys in monitoring constructed trails in such terrain is an onerous task for forest administrators, as hundreds of meters need to be surveyed per site, and the quantification of parameters and volumes is largely based on assumptions of trail symmetry and terrain uniformity. In this study, aerial imagery captured from a multi-rotor Unmanned Aerial Vehicle was used in generating a detailed post-harvest terrain model which included all skid trails. This was then compared with an Airborne Laser Scanning derived pre-harvest terrain model and the dimensions, slopes and cut-and-fill volumes associated with the skid trails were determined. The overall skid trail length was 954 m, or 381 m·ha−1 with segments varying from 40–60 m, inclinations from 3.9% to 9.6%, and cut volumes, from 1.7 to 3.7 m3 per running meter. The methods used in this work can be used in rapidly assessing the extent of disturbance and erosion risk on a wide range of sites. The multi-rotor Unmanned Aerial Vehicle (UAV was found to be highly suited to the task, given the relatively small size of harvested stands, their shape and their location in the mountainous terrain.

  10. Combine Harvester Simulator

    DEFF Research Database (Denmark)

    Vilmann, Ole; Sørlie, James Arnold

    1999-01-01

    A simulator for training pilots in the operation of a modern high-tech combine harvester is presented. The new simulator application is based on DMI´s well-known DMS maritime simulator architecture. Two major challenges have been encountered in the development of the simulator: 1) interfacing the...

  11. Harvesting soil with potatoes

    DEFF Research Database (Denmark)

    Egelyng, Henrik

    2017-01-01

    Norwegian authorities demand soil leaving potato packing plants to be deposited as waste. Depositing soil from potato processing plants is associated with significant cost for Norwegian producers. Therefore CYCLE investigated potato soil harvesting from an innovation and socio-economic perspective....

  12. Exporter Price Premia?

    DEFF Research Database (Denmark)

    Jäkel, Ina Charlotte; Sørensen, Allan

    This paper provides new evidence on manufacturing firms' output prices: in Denmark, on average, exported varieties are sold at a lower price (i.e. a negative exporter price premium) relative to only domestically sold varieties. This finding stands in sharp contrast to previous studies, which have...... found positive exporter price premia. We also document that the exporter price premium varies substantially across products (both in terms of sign and magnitude). We show that in a standard heterogeneous firms model with heterogeneity in quality as well as production efficiency there is indeed no clear......-cut prediction on the sign of the exporter price premium. However, the model unambiguously predicts a negative exporter price premium in terms of quality-adjusted prices, i.e. prices per unit of quality. This prediction is broadly borne out in the Danish data: while the magnitude of the premium varies across...

  13. Price strategy and pricing strategy: terms and content identification

    OpenAIRE

    Panasenko Tetyana

    2015-01-01

    The article is devoted to the terminology and content identification of seemingly identical concepts "price strategy" and "pricing strategy". The article contains evidence that the price strategy determines the direction, principles and procedure of implementing the company price policy and pricing strategy creates a set of rules and practical methods of price formation in accordance with the pricing strategy of the company.

  14. Designing A General Deep Web Harvester by Harvestability Factor

    NARCIS (Netherlands)

    Khelghati, Mohammadreza; van Keulen, Maurice; Hiemstra, Djoerd

    2014-01-01

    To make deep web data accessible, harvesters have a crucial role. Targeting different domains and websites enhances the need of a general-purpose harvester which can be applied to different settings and situations. To develop such a harvester, a large number of issues should be addressed. To have

  15. Timbered masonry for earthquake resistance in Europe

    Directory of Open Access Journals (Sweden)

    Dutu, A.

    2012-12-01

    Full Text Available Europe is a continent that is subject to significant seismic activity. Thus, the buildings’ seismic behaviour must be analysed, including not only the new structures, designed under more rigorous codes, but also older ones. This article examines a traditional type of building that uses timber frame/masonry, which is found in Portugal, Turkey, France, England, Greece, Romania, Italy, Spain, Germany and Scandinavia. Although the structures differ in terms of construction details, their structural system is basically the same: the wooden structural system bears mainly the horizontal loads while the masonry supports the gravity loads. The study includes a brief report on the seismicity of each country where this traditional type of building made of timbered framed masonry is found, together with the description of these buildings’ constructive systems.

    Europa es un continente que está sujeto a una significativa actividad sísmica. Por esta razón, se debe analizar el comportamiento sísmico, no sólo de las nuevas estructuras, diseñadas sobre la base de códigos más exigentes, sino también de los diversos tipos de estructuras antiguas. En este artículo se analizan las estructuras constituidas por mampostería y madera, que se pueden encontrar en Portugal, Turquía, Francia, Inglaterra, Grecia, Rumania, Italia, España, Alemania y Escandinavia. Aunque estas estructuras presentan diferencias en cuanto a detalles constructivos, su sistema estructural es idéntico: el sistema estructural de madera absorbe principalmente las cargas horizontales, mientras que la mampostería garantiza la resistencia a la acción de la gravedad. El estudio presentado incluye un breve informe acerca de la sismicidad de los países en que existe el tipo de construcción mencionado, conjuntamente con la descripción de los sistemas constructivos específicos de cada país.

  16. Valuation Struggles over Pricing

    DEFF Research Database (Denmark)

    Pallesen, Trine

    2016-01-01

    of creating political markets, and political prices, here understood as market distortion. This paper studies the ‘politics’ of pricing by following the adoption of the first feed-in tariff in France. Pricing as a way of achieving non-economic ends, such as climate mitigation, brings the values of several...... public goods into play, all the while prompting a translation of these values into a single price. Following the struggles over the pricing of wind power in the early 2000s, the study illustrates that rather than a pollution of the market sphere by that of politics, a politics of pricing can be observed...

  17. Magnetic Nanocomposite Cilia Energy Harvester

    KAUST Repository

    Khan, Mohammed Asadullah; Alfadhel, Ahmed; Kosel, Jü rgen

    2016-01-01

    An energy harvester capable of converting low frequency vibrations into electrical energy is presented. The operating principle, fabrication process and output characteristics at different frequencies are discussed. The harvester is realized

  18. Harvesting Adaptation to Biodiversity Conservation in Sawmill Industry: Technology Innovation and Monitoring Program

    Directory of Open Access Journals (Sweden)

    Guillermo J. Martínez Pastur

    2007-09-01

    Full Text Available Social demands related to native forest ecosystems are based on an efficient management, with a balance between conservation and timber production. This paper describes the industry adaptation to a biodiversity program with an alternative regeneration method. The proposed method leaves 30% of the timber-quality forest as aggregated retention and 15 m² ha-1 basal area as dispersed retention. While many costs increased considerably, the incomes also may increase by applying new management strategies and technology innovation. A monitoring program was established in the harvested stands to evaluate the ecological functionality of the applied regeneration system (forest structure, climate change, regeneration dynamics, habitat quality and abiotic cycles. The implementation of an innovated technology and monitoring program in the forest and industry determined a balance between economic values and biodiversity conservation.

  19. Harvest Regulations and Implementation Uncertainty in Small Game Harvest Management

    Directory of Open Access Journals (Sweden)

    Pål F. Moa

    2017-09-01

    Full Text Available A main challenge in harvest management is to set policies that maximize the probability that management goals are met. While the management cycle includes multiple sources of uncertainty, only some of these has received considerable attention. Currently, there is a large gap in our knowledge about implemention of harvest regulations, and to which extent indirect control methods such as harvest regulations are actually able to regulate harvest in accordance with intended management objectives. In this perspective article, we first summarize and discuss hunting regulations currently used in management of grouse species (Tetraonidae in Europe and North America. Management models suggested for grouse are most often based on proportional harvest or threshold harvest principles. These models are all built on theoretical principles for sustainable harvesting, and provide in the end an estimate on a total allowable catch. However, implementation uncertainty is rarely examined in empirical or theoretical harvest studies, and few general findings have been reported. Nevertheless, circumstantial evidence suggest that many of the most popular regulations are acting depensatory so that harvest bag sizes is more limited in years (or areas where game density is high, contrary to general recommendations. A better understanding of the implementation uncertainty related to harvest regulations is crucial in order to establish sustainable management systems. We suggest that scenario tools like Management System Evaluation (MSE should be more frequently used to examine robustness of currently applied harvest regulations to such implementation uncertainty until more empirical evidence is available.

  20. PRICES IN COMPETITIVE SYSTEM

    Directory of Open Access Journals (Sweden)

    VADUVA MARIA

    2017-08-01

    Full Text Available Regularities of competitive market determine rules for determining prices and their dynamics. Orientation prices to competition (competitive pricing is the strategy most frequently used in countries with market economies and especially for exports. Moreover, in an economy dominated by market competition it cannot be ignored without certain risks the prices resulting from competition between products bidders. Companies that use this type of strategy seek to maintain a level of prices linked to that charged by other competitors (or exporting producers generally no longer covering production costs or demand, relying on the assumption that the average market price is a reasonable basis of costs. But the way how practical guidance and reporting to the competition in every price strategy, will be determined by the company's market position, by the available power and enjoyed prestige, objectives and prospects of its market share etc. according to these elements, there may be several versions of pricing strategies oriented to competitors.

  1. Retail Price Model

    Science.gov (United States)

    The Retail Price Model is a tool to estimate the average retail electricity prices - under both competitive and regulated market structures - using power sector projections and assumptions from the Energy Information Administration.

  2. Natural gas pricing

    International Nuclear Information System (INIS)

    Freedenthal, C.

    1993-01-01

    Natural gas pricing is the heart and soul of the gas business. Price specifically affects every phase of the industry. Too low a price will result in short supplies as seen in the mid-1970s when natural gas was scarce and in tight supply. To fully understand the pricing of this energy commodity, it is important to understand the total energy picture. In addition, the effect and impact of world and US economies, and economics in general are crucial to understanding natural gas pricing. The purpose of this presentation will be to show the parameters going into US natural gas pricing including the influence of the many outside industry factors like crude oil and coal pricing, market drivers pushing the gas industry, supply/demand parameters, risk management for buyers and sellers, and other elements involved in pricing analysis

  3. Drug Pricing Reforms

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Mendez, Susan J.; Rønde, Thomas

    2015-01-01

    Reference price systems for prescription drugs have found widespread use as cost containment tools. Under such regulatory regimes, patients co-pay a fraction of the difference between pharmacy retail price of the drug and a reference price. Reference prices are either externally (based on drug...... prices in other countries) or internally (based on domestic drug prices) determined. In a recent study, we analysed the effects of a change from external to internal reference pricing in Denmark in 2005, finding that the reform led to substantial reductions in prices, producer revenues, and expenditures...... for patients and the health insurance system. We also estimated an increase in consumer welfare but the size effect depends on whether or not perceived quality differences between branded and other drugs are taken into account....

  4. NUKEM adjusts price definitions

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This article is the October-November 1994 market report, providing trading volume and prices in the Uranium market. During this period, there were five deals in the spot concentrates market, five deals in the medium and long-term market, one deal in the conversion market, and two deals in the enrichment market. Restricted prices strengthened while unrestricted prices held steady. Price re-definitions were also announced

  5. Delegating Pricing Decisions

    OpenAIRE

    Pradeep Bhardwaj

    2001-01-01

    An outstanding problem in marketing is why some firms in a competitive market delegate pricing decisions to agents and other firms do not. This paper analyzes the impact of competition on the delegation decision and, in turn, the impact of delegation on prices and incentives. The theory builds on the simplest framework of competition in two dimensions: prices and (sales agents') effort. Specifically, we are interested in answering the following questions: (1) Does competition affect the price...

  6. Piezoelectric energy harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Howells, Christopher A [Power Technology Branch, US Army, CERDEC, C2D, Ft. Belvoir, VA 22060-5816 (United States)

    2009-07-15

    Piezoelectric materials can be used to convert oscillatory mechanical energy into electrical energy. This technology, together with innovative mechanical coupling designs, can form the basis for harvesting energy from mechanical motion. Piezoelectric energy can be harvested to convert walking motion from the human body into electrical power. Recently four proof-of-concept Heel Strike Units were developed where each unit is essentially a small electric generator that utilizes piezoelectric elements to convert mechanical motion into electrical power in the form factor of the heel of a boot. The results of the testing and evaluation and the performance of this small electric generator are presented. The generator's conversion of mechanical motion into electrical power, the processes it goes through to produce useable power and commercial applications of the Heel Strike electric generator are discussed. (author)

  7. Piezoelectric energy harvesting

    International Nuclear Information System (INIS)

    Howells, Christopher A

    2009-01-01

    Piezoelectric materials can be used to convert oscillatory mechanical energy into electrical energy. This technology, together with innovative mechanical coupling designs, can form the basis for harvesting energy from mechanical motion. Piezoelectric energy can be harvested to convert walking motion from the human body into electrical power. Recently four proof-of-concept Heel Strike Units were developed where each unit is essentially a small electric generator that utilizes piezoelectric elements to convert mechanical motion into electrical power in the form factor of the heel of a boot. The results of the testing and evaluation and the performance of this small electric generator are presented. The generator's conversion of mechanical motion into electrical power, the processes it goes through to produce useable power and commercial applications of the Heel Strike electric generator are discussed.

  8. Restoration of harvested peatlands

    International Nuclear Information System (INIS)

    Saarmets, Tiit

    1999-01-01

    A short analysis of the main topics of the IPS Symposium Peatland Restoration and Reclamation, Duluth, Minnesota, USA, 1998 is given. It has been single-mindedly recommended in Estonia so far that harvested peatland surfaces should be levelled and outflows shut. But following these recommendations will lead to an unfounded formation of marshy areas with a very low growth of plants. The reclamation of harvested peatlands for agricultural purposes is expensive and there is no commercial need for agricultural land in today's Estonia now. In the author's opinion the foreflows and intermediate ditches should be left open which would favour the growth of the brushwood to grow later into the forest of commercial value. (author)

  9. Piezoelectric Energy Harvesting Solutions

    Science.gov (United States)

    Caliò, Renato; Rongala, Udaya Bhaskar; Camboni, Domenico; Milazzo, Mario; Stefanini, Cesare; de Petris, Gianluca; Oddo, Calogero Maria

    2014-01-01

    This paper reviews the state of the art in piezoelectric energy harvesting. It presents the basics of piezoelectricity and discusses materials choice. The work places emphasis on material operating modes and device configurations, from resonant to non-resonant devices and also to rotational solutions. The reviewed literature is compared based on power density and bandwidth. Lastly, the question of power conversion is addressed by reviewing various circuit solutions. PMID:24618725

  10. Harvesting contaminants from liquid

    Science.gov (United States)

    Simpson, John T.; Hunter, Scott R.

    2016-05-31

    Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a vessel for storing the contaminated fluid. The vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus allowing the contaminants to be harvested.

  11. Opinions of Forest Managers, Loggers, and Forest Landowners in North Carolina regarding Biomass Harvesting Guidelines

    Directory of Open Access Journals (Sweden)

    Diane Fielding

    2012-01-01

    Full Text Available Woody biomass has been identified as an important renewable energy source capable of offsetting fossil fuel use. The potential environmental impacts associated with using woody biomass for energy have spurred development of biomass harvesting guidelines (BHGs in some states and proposals for BHGs in others. We examined stakeholder opinions about BHGs through 60 semistructured interviews with key participants in the North Carolina, USA, forest business sector—forest managers, loggers, and forest landowners. Respondents generally opposed requirements for new BHGs because guidelines added to best management practices (BMPs. Most respondents believed North Carolina’s current BMPs have been successful and sufficient in protecting forest health; biomass harvesting is only an additional component to harvesting with little or no modification to conventional harvesting operations; and scientific research does not support claims that biomass harvesting negatively impacts soil, water quality, timber productivity, or wildlife habitat. Some respondents recognized possible benefits from the implementation of BHGs, which included reduced site preparation costs and increases in proactive forest management, soil quality, and wildlife habitat. Some scientific literature suggests that biomass harvests may have adverse site impacts that require amelioration. The results suggest BHGs will need to be better justified for practitioners based on the scientific literature or linked to demand from new profitable uses or subsidies to offset stakeholder perceptions that they create unnecessary costs.

  12. Price competition on graphs

    NARCIS (Netherlands)

    Soetevent, A.R.

    2010-01-01

    This paper extends Hotelling's model of price competition with quadratic transportation costs from a line to graphs. I propose an algorithm to calculate firm-level demand for any given graph, conditional on prices and firm locations. One feature of graph models of price competition is that spatial

  13. Press point on prices

    International Nuclear Information System (INIS)

    Schilansky, J.L.

    2005-06-01

    This document presents information and statistical data on the prices of the crude oils, refining and petroleum products, at the date of the 28 June 2005: evolution of the barrel price, supply and demand, geo-policy, consumption, diesel and gasoline, prices at the service station. (A.L.B.)

  14. Price control and macromarketing

    Directory of Open Access Journals (Sweden)

    Kancir Rade

    2003-01-01

    Full Text Available Price control at macro level is part of integral macro marketing strategic control system, or more precisely, part of social marketing mix control. Price impact is direct, if it is regarded in the context of needs satisfaction, and indirect, within the context of resource allocation. These two patterns of price impact define control mechanism structuring. Price control in sense of its direct impact at process of need satisfaction should comprise qualitative and quantitative level of needs satisfaction at a given price level and its structure, informational dimension of price and different disputable forms of corporate pricing policies. Control of price allocation function is based at objectives of macro marketing system management in the area of resource allocation and the role of price as allocator in contemporary market economies. Control process is founded, on one hand, at theoretical models of correlation between price and demand in different market structures, and on the other hand, at complex limits that price as allocator has, and which make whole control process even more complex because of reduction of the degree of determinism in functioning of contemporary economic systems. Control of price allocation function must be continuous and dynamic process if it is to provide for convergence with environmental changes and if it is to provide for placing control systems at micro marketing levels in the function of socially valid objectives.

  15. Simulating Price-Taking

    Science.gov (United States)

    Engelhardt, Lucas M.

    2015-01-01

    In this article, the author presents a price-takers' market simulation geared toward principles-level students. This simulation demonstrates that price-taking behavior is a natural result of the conditions that create perfect competition. In trials, there is a significant degree of price convergence in just three or four rounds. Students find this…

  16. Dutch house price fundamentals

    NARCIS (Netherlands)

    Haffner, M.E.A.; de Vries, P.

    2009-01-01

    This paper discusses house price developments in the Netherlands, specifically focussing on the question whether current house prices in the Dutch owner-occupied market are likely to decrease. We analyse three aspects of the question based on a literature review: (1) whether there is a house price

  17. Terra Harvest software architecture

    Science.gov (United States)

    Humeniuk, Dave; Klawon, Kevin

    2012-06-01

    Under the Terra Harvest Program, the DIA has the objective of developing a universal Controller for the Unattended Ground Sensor (UGS) community. The mission is to define, implement, and thoroughly document an open architecture that universally supports UGS missions, integrating disparate systems, peripherals, etc. The Controller's inherent interoperability with numerous systems enables the integration of both legacy and future UGS System (UGSS) components, while the design's open architecture supports rapid third-party development to ensure operational readiness. The successful accomplishment of these objectives by the program's Phase 3b contractors is demonstrated via integration of the companies' respective plug-'n'-play contributions that include controllers, various peripherals, such as sensors, cameras, etc., and their associated software drivers. In order to independently validate the Terra Harvest architecture, L-3 Nova Engineering, along with its partner, the University of Dayton Research Institute, is developing the Terra Harvest Open Source Environment (THOSE), a Java Virtual Machine (JVM) running on an embedded Linux Operating System. The Use Cases on which the software is developed support the full range of UGS operational scenarios such as remote sensor triggering, image capture, and data exfiltration. The Team is additionally developing an ARM microprocessor-based evaluation platform that is both energy-efficient and operationally flexible. The paper describes the overall THOSE architecture, as well as the design decisions for some of the key software components. Development process for THOSE is discussed as well.

  18. Analyzing the effects of past prices on reference price formation

    OpenAIRE

    van Oest, R.D.; Paap, R.

    2004-01-01

    textabstractWe propose a new reference price framework for brand choice. In this framework, we employ a Markov-switching process with an absorbing state to model unobserved price recall of households. Reference prices result from the prices households are able to remember. Our model can be used to learn how many prices observed in the past are used for reference price formation. Furthermore, we learn to what extent households have sufficient price knowledge to form an internal reference price...

  19. 36 CFR 13.485 - Subsistence use of timber and plant material.

    Science.gov (United States)

    2010-07-01

    ... cutting of standing timber by local rural residents for appropriate subsistence uses, such as firewood or... materials for subsistence uses, and the noncommerical gathering of dead or downed timber for firewood, shall...

  20. Evaluation of Forest Dynamics Focusing on Various Minimum Harvesting Ages in Multi-Purpose Forest Management Planning

    Directory of Open Access Journals (Sweden)

    Derya Mumcu Kucuker

    2015-04-01

    Full Text Available Aim of study: Exploring the potential effects of various forest management strategies on the ability of forest ecosystems to sequester carbon and produce water has become of great concern among forest researchers. The main purpose of this study is to evaluate the effects of management strategies with different minimum harvesting ages on the amount and monetary worth of carbon, water and timber values. Area of study: The study was performed in the Yalnızçam planning unit located on the northeastern part of Turkey. Material and Methods: A forest management model with linear programming (LP was developed to determine the effects of various minimum harvesting ages. Twenty-four different management strategies were developed to maximize the economic Net Present Value (NPV of timber, water and carbon values in addition to their absolute quantities over time. Amount and NPV of forest values and ending inventory with different minimum harvesting ages were used as performance indicators to assess and thus understand forest dynamics. Main results: Amount and NPV of timber and carbon generally decreased with extended minimum harvesting ages. However, similar trends were not observed for water production values. The results pointed out that the performance of a management strategy depends highly on the development of a management strategy and the initial forest structure aside from the growth rate Research highlights: Minimum harvesting ages affect forest outputs under the same objectives and constraints. Performance of a management strategy highly depends on initial age class structure in addition to the contents of a management strategy.

  1. Internet resource pricing models

    CERN Document Server

    Xu, Ke; He, Huan

    2013-01-01

    This brief guides the reader through three basic Internet resource pricing models using an Internet cost analysis. Addressing the evolution of service types, it presents several corresponding mechanisms which can ensure pricing implementation and resource allocation. The authors discuss utility optimization of network pricing methods in economics and underline two classes of pricing methods including system optimization and entities' strategic optimization. The brief closes with two examples of the newly proposed pricing strategy helping to solve the profit distribution problem brought by P2P

  2. Value-based pricing

    Directory of Open Access Journals (Sweden)

    Netseva-Porcheva Tatyana

    2010-01-01

    Full Text Available The main aim of the paper is to present the value-based pricing. Therefore, the comparison between two approaches of pricing is made - cost-based pricing and value-based pricing. The 'Price sensitively meter' is presented. The other topic of the paper is the perceived value - meaning of the perceived value, the components of perceived value, the determination of perceived value and the increasing of perceived value. In addition, the best company strategies in matrix 'value-cost' are outlined. .

  3. Harvesting and replenishment policies for renewable natural resources

    Science.gov (United States)

    Douglas, Aaron J.; Johnson, Richard L.

    1993-01-01

    The current paper links the optimal intertemporal use of renewable natural resources to the harvesting activities of various economic agents. Previous contributions cite market forces as a causative factor inducing the extirpation of renewable natural resources. The analysis given here discusses investment in the stock of renewable resources and cites important examples of this activity. By introducing joint harvesting and replenishment strategies into a model of renewable resource use, the analysis adds descriptive reality and relevance to positive and normative discussions of renewable natural resource use. A high price for the yield or a high discount rate tend to diminish the size of the optimum stationary stock of the resource with a non-replenishment harvesting strategy. Optimal non-replenishment harvesting strategies for renewable natural resources will exhaustion or extirpation of the resource if the price of the yield or the discount rate are sufficiently large. However, the availability of a replenishment technology and the use of replenishment activities tends to buffer the resource against exhaustion or extirpation.

  4. Protection of timber constructions by using electro osmotic pulsing technology (PLEOT)

    OpenAIRE

    Treu, A.; Larnoy, E.; Ribeiro Nunes, L. M.; Duarte, S.; Halvorsen, H.

    2011-01-01

    Timber constructions are often built in combination with other materials such as concrete. These materials can influence the timber construction. Moist concrete can e.g. lead to development of molds which creates an unhealthy living area for people. Furthermore, moisture in wood buildings can negatively affect the wood material, which can lead to negative biological activity in timber and possible reduction of strength properties of timber constructions. The present paper introduces ...

  5. A Probabilistic Approach for Robustness Evaluation of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    of Structures and a probabilistic modelling of the timber material proposed in the Probabilistic Model Code (PMC) of the Joint Committee on Structural Safety (JCSS). Due to the framework in the Danish Code the timber structure has to be evaluated with respect to the following criteria where at least one shall...... to criteria a) and b) the timber frame structure has one column with a reliability index a bit lower than an assumed target level. By removal three columns one by one no significant extensive failure of the entire structure or significant parts of it are obatined. Therefore the structure can be considered......A probabilistic based robustness analysis has been performed for a glulam frame structure supporting the roof over the main court in a Norwegian sports centre. The robustness analysis is based on the framework for robustness analysis introduced in the Danish Code of Practice for the Safety...

  6. Reliability Analysis of Timber Structures through NDT Data Upgrading

    DEFF Research Database (Denmark)

    Sousa, Hélder; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    The first part of this document presents, in chapter 2, a description of timber characteristics and common used NDT and MDT for timber elements. Stochastic models for timber properties and damage accumulation models are also referred. According to timber’s properties a framework is proposed...... for a safety reassessment procedure. For that purpose a theoretical background for structural reliability assessment including probabilistic concepts for structural systems and stochastic models are given in chapter 3. System models, both series and parallel systems, are presented as well as methods...... for robustness are dealt in chapter 5. The second part of this document begins in chapter 6, where a practical application of the premise definitions and methodologies is given through the implementation of upgraded models with NDT and MDT data. Structural life-cycle is, therefore, assessed and reliability...

  7. Multi-Scalar Modelling for Free-form Timber Structures

    DEFF Research Database (Denmark)

    Poinet, Paul; Nicholas, Paul; Tamke, Martin

    2016-01-01

    .The research explores the design probe of free-form structures composed of glue-laminated timber beams and looks at the different types of data that need to be shared among each discipline and across multiple scales from which different levels of resolution can be defined. A particular focus lies...... in the segmentation strategy of glue-laminated timber structures that depend on structural requirements and the different types of constraints related to fabrication, transportation and assembly. Where current working practices decouple segmentation processes within a discrete digital workflow, this research aims...... and techniques as a means to work within a continuous design environment in which an abstract network of timber beams is iteratively updated through geometrical and structural optimizations at different levels of resolution....

  8. Development of a six-year research needs assessment for timber transportation structures

    Science.gov (United States)

    Terry J. Wipf; Michael A. Ritter; Sheila Rimal Duwadi; Russell C. Moody

    1993-01-01

    A timber bridge, once a thing of the past, is now becoming a thing of the present. Interest in timber bridges and other transportation structures has been rapidly increasing. Much of this is due to new technologies in design and construction as well as advances in material manufacturing and presevative treatments. Although timber bridges and other transportation...

  9. Forensic timber identification: It's time to integrate disciplines to combat illegal logging

    Science.gov (United States)

    Eleanor E. Dormontt; Markus Boner; Birgit Braun; Gerhard Breulmann; Bernd Degen; Edgard Espinoza; Shelley Gardner; Phil Guillery; John C. Hermanson; Gerald Koch; Soon Leong Lee; Milton Kanashiro; Anto Rimbawanto; Darren Thomas; Alex C. Wiedenhoeft; Yafang Yin; Johannes Zahnen; Andrew J. Lowe

    2015-01-01

    The prosecution of illegal logging crimes is hampered by a lack of available forensic timber identification tools, both for screening of suspectmaterial and definitive identification of illegally sourcedwood. Reputable timber traders are also struggling to police their own supply chains and comply with the growing requirement for due diligence with respect to timber...

  10. Robustness Analysis of a Timber Structure with Ductile Behaviour in Compression

    DEFF Research Database (Denmark)

    Čizmar, Dean; Sørensen, John Dalsgaard; Kirkegaard, Poul Henning

    2011-01-01

    This paper presents a probabilistic approach for structural robustness assessment for a timber structure built a few years ago. The robustness analysis is based on a structural reliability based framework for robustness assessment. The complex timber structure with a large number of failure modes...... material ductility of timber is taken into account. The robustness is expressed and evaluated by a robustness index....

  11. 36 CFR 294.24 - Timber cutting, sale, or removal in Idaho Roadless Areas.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Timber cutting, sale, or..., DEPARTMENT OF AGRICULTURE SPECIAL AREAS Idaho Roadless Area Management § 294.24 Timber cutting, sale, or removal in Idaho Roadless Areas. (a) Wild Land Recreation. The cutting, sale, or removal of timber is...

  12. Governance of private forests in Eastern and Central Europe: An analysis of forest harvesting and management rights

    Directory of Open Access Journals (Sweden)

    Laura Bouriaud

    2013-05-01

    Full Text Available A property rights-based approach is proposed in the paper to underlinethe common characteristics of the forest property rights specificationin ten ECE countries, the specific patterns governing the harvesting of timber in private forestry and the role of the forest management planning in determining the content of the property rights. The analysis deals with the private forests of the individuals (non industrial ownership from ten countries, covering 7.3 million ha and producing yearly some 25 million timber. The study shows that the forest management rights in private forests belong to the State and that the withdrawal rights on timber, yet recognized in the forest management plans, are in reality strongly restricted from aneconomic viewpoint. The forest management planning is the key instrument of the current forest governance system, based on top-down, hierarchically imposed and enforced set of compulsory rules on timber harvesting. With few exceptions, the forest owners’ have little influence in the forest planning and harvesting. The rational and State-lead approach of the private forest management has serious implications not only on the economic content of the property rights, but also on the learning and adaptive capacity of private forestry to cope with current challenges such the climate change, the increased industry needs for wood as raw material, or the marketingof innovative non wood forest products and services. The study highlights that understanding and comparing the regime of the forest ownership require a special analysis of the economic rights attached to each forest attribute; and that the evolution towards more participatory decision-making in the local forest governance can not be accurately assessed in ECE region without a proper understanding of the forest management planning process.

  13. Governance of private forests in Eastern and Central Europe: An analysis of forest harvesting and management rights

    Directory of Open Access Journals (Sweden)

    Laura Bouriaud

    2013-07-01

    Full Text Available A property rights-based approach is proposed in the paper to underline the common characteristics of the forest property rights specification in ten ECE countries, the specific patterns governing the harvesting of timber in private forestry and the role of the forest management planning in determining the content of the property rights. The analysis deals with the private forests of the individuals (non industrial ownership from ten countries, covering 7.3 million ha and producing yearly some 25 million m3 timber. The study shows that the forest management rights in private forests belong to the State and that the withdrawal rights on timber, yet recognised in the forest management plans, are in reality strongly restricted from an economic viewpoint. The forest management planning is the key instrument of the current forest governance system, based on top-down, hierarchically imposed and enforced set of compulsory rules on timber harvesting. With few exceptions, the forest owners’ have little influence in the forest planning and harvesting. The rational and State-lead approach of the private forest management has serious implications not only on the economic content of the property rights, but also on the learning and adaptive capacity of private forestry to cope with current challenges such the climate change, the increased industry needs for wood as raw material, or the marketing of innovative non wood forest products and services. The study highlights that understanding and comparing the regime of the forest ownership require a special analysis of the economic rights attached to each forest attribute; and that the evolution towards more participatory decision-making in the local forest governance can not be accurately assessed in ECE region without a proper understanding of the forest management planning process. 

  14. Protection of mechanized timberings on beds dangerous for mine impacts

    Energy Technology Data Exchange (ETDEWEB)

    Budirsky, S

    1982-01-01

    In some stoping faces on beds which are dangerous for mine impacts, mechanized timbering is successfully used which is not equipped with protection from the effect of these dynamic phenomena. This generated the idea that in the indicated conditions, mechanized timbering may not be equipped with protective devices against dynamic loads. Theoretical studies have shown that the effects of mine impacts depends on the total energy of the impact, distance of this stoping face from the epicenter of the impact, as well as the capacity of the rock massif to transmit and absorb energy of the mine impact. This means that the effect of the mine impact under different conditions is not the same, the mine impacts of lower energy under definite conditions can result in greater damages to the mechanized timbering than mine impact with higher energy. It is believed that the effect of absorption of energy of the mine impact depends on the method of control of the roofing in the stoping face, the presence of hydraulic fill quarantees absorption of up to 80% of its energy. The experience of working beds which are dangerous for mine impacts in the upper Silesia coal basin indicated that the designs of the mechanized timbering, especially shield, in which the stands are not rigidly connected to the roof timber, during operation on beds with thickness 2.5-4 m withstand mine impacts with energy 10/sup 7/ J without significant disorders (mine impacts with this energy occur very frequently . For energy of mine impact of 108 J (impacts with this energy are observed comparatively rarely), the mechanized timberings are considerably damaged.

  15. A Model to Estimate Willingness to Pay for Harvest Permits for Wild Edible Mushrooms: Application to Andalusian Forests

    Directory of Open Access Journals (Sweden)

    Pablo de Frutos

    2016-11-01

    Full Text Available Public demand for harvesting wild edible mushrooms has risen in recent decades and currently affects many forested areas around the world. The idea of introducing permits for users has been conceived as a tool for ecosystem management. The problem is that policy-makers lack the necessary means to help guide them when establishing prices for such harvesting permits. Valuing the recreational benefits which mushroom harvesters derive from harvesting wild edible mushrooms may provide certain guidelines as to how much people would be willing to pay and may also justify future payments levied on harvesters. The aim of the present article is to estimate a model for determining citizens’ willingness to pay for a harvesting permit in a forest in Andalusia (Spain using contingent valuation methods. Results show that mean willingness to pay is 22.61 Euros (USD28.18 per harvester and season. This amount depends on several socioeconomic factors and preferences related to harvesters’ experiences.

  16. Theory of timber connections with slender dowel type fasteners

    DEFF Research Database (Denmark)

    Svensson, Staffan; Munch-Andersen, Jørgen

    2018-01-01

    A theory on the lateral load-carrying capacity of timber connections with slender fasteners is presented. The base of the theory is the coupled mechanical phenomena acting in the connection, while the wood and the slender fastener deform and yield prior to failure. The objective is to derive...... a sufficient description of actions and responses which have determining influence on the load-carrying capacity of timber connections with slender fasteners. Model assumptions are discussed and made, but simplifications are left out. Even so, simple mathematical equations describing the lateral capacity......-carrying capacity of the tested connections....

  17. Global timber trade pattern: the cards have changed

    OpenAIRE

    Roda Jean-Marc; Rohana Abd Rahman; Ismariah Ahmad; Lim Hin Fui; Mohd Parid Mamat

    2011-01-01

    Since the 1960s, the global timber trade has gradually evolved from a South-North trade to a South-South trade, with an acceleration of the phenomenon in the mid 1990s. Nowadays, Asia consumes more than 70% (in round wood equivalent) of the forest products originating from the tropics. Africa becomes the new frontier for the supplies of wood material for Asian giants, which now source raw wood from all over the world. Since the mid 1990s, the dynamics of the tropical timber trade have been in...

  18. Fire resistance in American heavy timber construction history and preservation

    CERN Document Server

    Heitz, Jesse

    2016-01-01

    This volume presents a history of heavy timber construction (HTC) in the United States, chronicling nearly two centuries of building history, from inception to a detailed evaluation of one of the best surviving examples of the type, with an emphasis on fire resistance. The book does not limit itself in scope to serving only as a common history. Rather, it provides critical analysis of HTC in terms of construction methods, design, technical specifications, and historical performance under fire conditions. As such, this book provides readers with a truly comprehensive understanding and exploration of heavy timber construction in the United States and its performance under fire conditions.

  19. Pre-Stressing Timber-Based Plate Tensegrity Structures

    DEFF Research Database (Denmark)

    Falk, Andreas; Kirkegaard, Poul Henning

    2012-01-01

    Tensile structures occur in numerous varieties utilising combinations of tension and compression. Introducing structural plates in the basic tensegrity unit and tensegric assemblies varies the range of feasible topologies and provides the structural system with an integrated surface. The present...... paper considers the concept of plate tensegrity based on CLT plates (cross-laminated timber). It combines the principles of tensegrity with the principles of plate shells and is characterised by a plate shell stabilised by struts and cables. The paper deals with material aspects and robustness of timber...

  20. Differential fat harvesting

    Directory of Open Access Journals (Sweden)

    Sebastian Torres Farr

    2014-12-01

    Full Text Available Aim: Volume replacement with fillers is regularly performed with the use of diverse volumetric materials to correct different structures around the face, depending on the volume enhancement required and the thickness of the soft tissue envelope. Differential fat harvesting and posterior grafting is performed to place the correct fat parcel size for each target area, expanding the potential applications of fat. Methods: Sixty patients consecutively recruited on a first come basis undergone a facial fat grafting procedure, in private practice setting between March 2012 and October 2013. Fat grafting quantity and quality was predicted for each case. Differential harvesting was performed, with 2 fat parcels size. Processing was performed through washing. Fat infiltration was carried out through small cannulas or needles depending on the treated area. Outcomes were analysed both by the physicians and the patients at 7 days, 1 month, 3 months and 6 months through a perceived satisfaction questionnaire. Parameters considered were downtime or discomfort, skin benefits, volume restoration, reabsorption rate estimated and overall improvement. Results: Full facial differential fat grafting procedure lasted an average of 1.5-2.5 h. Average downtime was 3-4 days. Follow-up was performed to a minimum of 6 months. Both patient and physician overall satisfaction rates were mostly excellent. Adverse events like lumps or irregularities were not encountered. Conclusion: Differential fat harvesting and posterior grafting is a valid alternative, to expand the repertoire of fat use, allow a more homogeneous effect, reduce the potential complications, speed up the process, improve graft survival, and to enhance overall aesthetic outcome.

  1. Analysis of the Strength of Timber and Glulam Timber Beams with Steel Reinforcement

    Directory of Open Access Journals (Sweden)

    Arie Putra Usman

    2015-12-01

    Full Text Available Indonesia is a tropical country with abundant tropical timber that can be used as a building material. Wood is a renewable material, thus making it an environmentally friendly construction material. However, the dimensional limitations of solid wood may pose problems in structural constructions. Wood material also has some disadvantages, such as brittle failure. However, the ductility of wood can be increased because of plasticity occurring in the compression zone. Wood material with good ductility can be obtained by reinforcing it in the tensile zone. This study is about the strength of wood material for use as a material for structural elements. Based on the analytical findings, the bending capacity of wood can be improved by adding reinforcements to the tensile zone.

  2. Nanostructured piezoelectric energy harvesters

    CERN Document Server

    Briscoe, Joe

    2014-01-01

    This book covers a range of devices that use piezoelectricity to convert mechanical deformation into electrical energy and relates their output capabilities to a range of potential applications. Starting with a description of the fundamental principles and properties of piezo- and ferroelectric materials, where applications of bulk materials are well established, the book shows how nanostructures of these materials are being developed for energy harvesting applications. The authors show how a nanostructured device can be produced, and put in context some of the approaches that are being invest

  3. Micro energy harvesting

    CERN Document Server

    Briand, Danick; Roundy, Shad

    2015-01-01

    With its inclusion of the fundamentals, systems and applications, this reference provides readers with the basics of micro energy conversion along with expert knowledge on system electronics and real-life microdevices. The authors address different aspects of energy harvesting at the micro scale with a focus on miniaturized and microfabricated devices. Along the way they provide an overview of the field by compiling knowledge on the design, materials development, device realization and aspects of system integration, covering emerging technologies, as well as applications in power management, e

  4. Reconciling Biodiversity Conservation and Timber Production in Mixed Uneven-Aged Mountain Forests: Identification of Ecological Intensification Pathways.

    Science.gov (United States)

    Lafond, Valentine; Cordonnier, Thomas; Courbaud, Benoît

    2015-11-01

    Mixed uneven-aged forests are considered favorable to the provision of multiple ecosystem services and to the conciliation of timber production and biodiversity conservation. However, some forest managers now plan to increase the intensity of thinning and harvesting operations in these forests. Retention measures or gap creation are considered to compensate potential negative impacts on biodiversity. Our objectives were to assess the effect of these management practices on timber production and biodiversity conservation and identify potential compensating effects between these practices, using the concept of ecological intensification as a framework. We performed a simulation study coupling Samsara2, a simulation model designed for spruce-fir uneven-aged mountain forests, an uneven-aged silviculture algorithm, and biodiversity models. We analyzed the effect of parameters related to uneven-aged management practices on timber production, biodiversity, and sustainability indicators. Our study confirmed that the indicators responded differently to management practices, leading to trade-offs situations. Increasing management intensity had negative impacts on several biodiversity indicators, which could be partly compensated by the positive effect of retention measures targeting large trees, non-dominant species, and deadwood. The impact of gap creation was more mitigated, with a positive effect on the diversity of tree sizes and deadwood but a negative impact on the spruce-fir mixing balance and on the diversity of the understory layer. Through the analysis of compensating effects, we finally revealed the existence of possible ecological intensification pathways, i.e., the possibility to increase management intensity while maintaining biodiversity through the promotion of nature-based management principles (gap creation and retention measures).

  5. Reductions in emissions from deforestation from Indonesia’s moratorium on new oil palm, timber, and logging concessions

    Science.gov (United States)

    Busch, Jonah; Ferretti-Gallon, Kalifi; Engelmann, Jens; Wright, Max; Austin, Kemen G.; Stolle, Fred; Turubanova, Svetlana; Potapov, Peter V.; Margono, Belinda; Hansen, Matthew C.; Baccini, Alessandro

    2015-01-01

    To reduce greenhouse gas emissions from deforestation, Indonesia instituted a nationwide moratorium on new license areas (“concessions”) for oil palm plantations, timber plantations, and logging activity on primary forests and peat lands after May 2011. Here we indirectly evaluate the effectiveness of this policy using annual nationwide data on deforestation, concession licenses, and potential agricultural revenue from the decade preceding the moratorium. We estimate that on average granting a concession for oil palm, timber, or logging in Indonesia increased site-level deforestation rates by 17–127%, 44–129%, or 3.1–11.1%, respectively, above what would have occurred otherwise. We further estimate that if Indonesia’s moratorium had been in place from 2000 to 2010, then nationwide emissions from deforestation over that decade would have been 241–615 MtCO2e (2.8–7.2%) lower without leakage, or 213–545 MtCO2e (2.5–6.4%) lower with leakage. As a benchmark, an equivalent reduction in emissions could have been achieved using a carbon price-based instrument at a carbon price of $3.30–7.50/tCO2e (mandatory) or $12.95–19.45/tCO2e (voluntary). For Indonesia to have achieved its target of reducing emissions by 26%, the geographic scope of the moratorium would have had to expand beyond new concessions (15.0% of emissions from deforestation and peat degradation) to also include existing concessions (21.1% of emissions) and address deforestation outside of concessions and protected areas (58.7% of emissions). Place-based policies, such as moratoria, may be best thought of as bridge strategies that can be implemented rapidly while the institutions necessary to enable carbon price-based instruments are developed. PMID:25605880

  6. 7 CFR 1131.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1131.53 Section 1131.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  7. 7 CFR 1005.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1005.53 Section 1005.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  8. 7 CFR 1124.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1124.53 Section 1124.53 Agriculture Regulations of the Department of Agriculture... Announcement of class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  9. 7 CFR 1126.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1126.53 Section 1126.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  10. 7 CFR 1032.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1032.53 Section 1032.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  11. 7 CFR 1030.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1030.53 Section 1030.53 Agriculture Regulations of the Department of Agriculture... of class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  12. 7 CFR 1033.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1033.53 Section 1033.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  13. 7 CFR 1001.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1001.53 Section 1001.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  14. 7 CFR 1007.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1007.53 Section 1007.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  15. 7 CFR 1006.53 - Announcement of class prices, component prices, and advanced pricing factors.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Announcement of class prices, component prices, and advanced pricing factors. 1006.53 Section 1006.53 Agriculture Regulations of the Department of Agriculture... class prices, component prices, and advanced pricing factors. See § 1000.53. ...

  16. Arbitrage Pricing, Capital Asset Pricing, and Agricultural Assets

    OpenAIRE

    Louise M. Arthur; Colin A. Carter; Fay Abizadeh

    1988-01-01

    A new asset pricing model, the arbitrage pricing theory, has been developed as an alternative to the capital asset pricing model. The arbitrage pricing theory model is used to analyze the relationship between risk and return for agricultural assets. The major conclusion is that the arbitrage pricing theory results support previous capital asset pricing model findings that the estimated risk associated with agricultural assets is low. This conclusion is more robust for the arbitrage pricing th...

  17. Price strategy and pricing strategy: terms and content identification

    Directory of Open Access Journals (Sweden)

    Panasenko Tetyana

    2015-11-01

    Full Text Available The article is devoted to the terminology and content identification of seemingly identical concepts "price strategy" and "pricing strategy". The article contains evidence that the price strategy determines the direction, principles and procedure of implementing the company price policy and pricing strategy creates a set of rules and practical methods of price formation in accordance with the pricing strategy of the company.

  18. STS pricing policy

    Science.gov (United States)

    Lee, C. M.; Stone, B.

    1982-01-01

    In 1977 NASA published Shuttle Reimbursement Policies for Civil U.S. Government, DOD and Commercial and Foreign Users. These policies were based on the principle of total cost recovery over a period of time with a fixed flat price for initial period to time to enhance transition. This fixed period was to be followed with annual adjustments thereafter, NASA is establishing a new price for 1986 and beyond. In order to recover costs, that price must be higher than the initial fixed price through FY 1985. NASA intends to remain competitive. Competitive posture includes not only price, but other factors such as assured launch, reliability, and unique services. NASA's pricing policy considers all these factors.

  19. Target Price Accuracy

    Directory of Open Access Journals (Sweden)

    Alexander G. Kerl

    2011-04-01

    Full Text Available This study analyzes the accuracy of forecasted target prices within analysts’ reports. We compute a measure for target price forecast accuracy that evaluates the ability of analysts to exactly forecast the ex-ante (unknown 12-month stock price. Furthermore, we determine factors that explain this accuracy. Target price accuracy is negatively related to analyst-specific optimism and stock-specific risk (measured by volatility and price-to-book ratio. However, target price accuracy is positively related to the level of detail of each report, company size and the reputation of the investment bank. The potential conflicts of interests between an analyst and a covered company do not bias forecast accuracy.

  20. Thermoelectrics and its energy harvesting

    National Research Council Canada - National Science Library

    Rowe, David Michael

    2012-01-01

    .... It details the latest techniques for the preparation of thermoelectric materials employed in energy harvesting, together with advances in the thermoelectric characterisation of nanoscale material...

  1. Pricing of new vaccines

    OpenAIRE

    Lee, Bruce Y; McGlone, Sarah M

    2010-01-01

    New vaccine pricing is a complicated process that could have substantial long-standing scientific, medical and public health ramifications. Pricing can have a considerable impact on new vaccine adoption and, thereby, either culminate or thwart years of research and development and public health efforts. Typically, pricing strategy consists of the following eleven components: (1) Conduct a target population analysis; (2) Map potential competitors and alternatives; (3) Construct a vaccine targe...

  2. Land Prices and Fundamentals

    OpenAIRE

    Koji Nakamura; Yumi Saita

    2007-01-01

    This paper examines the long-term relationship between macro economic fundamentals and the weighted-average land price indicators, which are supposed to be more appropriate than the official land price indicators when analyzing their impacts on the macro economy. In many cases, we find the cointegrating relationships between the weighted-average land price indicators and the discounted present value of land calculated based on the macro economic fundamentals indicators. We also find that the ...

  3. Introduction to pricing issues

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This chapter provides an overview of pricing issues the proper pricing of transmission services is essential to efficient operation of the grid. Wheeling rights have little meaning if capacity on existing lines is scarce and there is no incentive to build new lines. Depending on the type of transmission pricing policies FERC adopts, the Commission may be able to encourage more voluntary wheeling service, and to influence decisions to build or upgrade the supply of facilities

  4. Cost and Price Collaboration

    Science.gov (United States)

    2016-04-30

    described below which relies on questionnaires administered to subject matter experts in both cost analysis and price analysis to determine the value of...additional reports or data that the price analyst used in determining their final negotiated position. The cost analyst section of the questionnaire...an analysis at the individual element level rather than at a total price level to determine the major changes from the awarded contract to the new

  5. Sustainable Harvest for Food and Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Grosshans, Raymond R.; Kostelnik, Kevin, M.; Jacobson, Jacob J.

    2007-04-01

    The DOE Biomass Program recently implemented the Biofuels Initiative, or 30x30 program, with the dual goal of reducing U.S. dependence on foreign oil by making cellulosic ethanol cost competitive with gasoline by 2012 and by replacing 30 percent of gasoline consumption with biofuels by 2030. Experience to date with increasing ethanol production suggests that it distorts agricultural markets and therefore raises concerns about the sustainability of the DOE 30 X 30 effort: Can the U.S. agricultural system produce sufficient feedstocks for biofuel production and meet the food price and availability expectations of American consumers without causing environmental degradation that would curtail the production of both food and fuel? Efforts are underway to develop computer-based modeling tools that address this concern and support the DOE 30 X 30 goals. Beyond technical agronomic and economic concerns, however, such models must account for the publics’ growing interest in sustainable agriculture and in the mitigation of predicted global climate change. This paper discusses ongoing work at the Center for Advanced Energy Studies that investigates the potential consequences and long-term sustainability of projected biomass harvests by identifying and incorporating “sustainable harvest indicators” in a computer modeling strategy.

  6. Harvest facility protects and improves fishery

    International Nuclear Information System (INIS)

    Hampton, T.; Daley, W.

    1991-01-01

    This paper reports that by constructing a trap and transfer/harvest facility to control anadromous fish migration, the trout fishery on the Boardman River was protected and the salmon fishery was improved. The James P. Price Fish Trap and Transfer/Harvest Facility at Traverse City, Michigan, was constructed by the Traverse City Light and Power Department because of a licensing condition during the redevelopment of the Boardman and Sabin hydroelectric plants. The facility was constructed along with a fish ladder at the Union Street Dam to control the anadromous fish migration in lieu of constructing fish ladders at the Union Street, Sabin and Boardman Dams. The Michigan Department of Natural Resources (MDNR) and the U.S. Fish and Wildlife Service required that the fish ladders be constructed before the hydroelectric plants could be reactivated. The MDNR was also planning to introduce salmon into the Boardman River as far up as the reservoir of the Boardman Dam, which is the third dam from the mouth of the river

  7. 1988 coal price negotiation

    Energy Technology Data Exchange (ETDEWEB)

    Senmura, Akira

    1988-12-01

    In the negotiation on raw coal price for 1988, which began at the end of 1987, Australia requested price rise of 4 - 5 dollars for the reason of rise of Australian dollars, conditions of mines, price drop in the past five years, and world supply/demand of coal. Japan insisted to maintain the price of preceding year. The talk ended in a dead lock which could last a long time. Negotiation on the Canadian coal price also encountered difficulties but an agreement was obtained in March as Japan accepted the increased price. After which, Japan and Australia agreed to raise the price by 2.90 dollars and an increase over last year. Producing countries also requested a wide price rise as 7.50 dollars for general coal, making in this area very difficult to progress. Finally, they agreed to raise the price by 6.30 dollars and the electric power utility in Japan responded by importing of U.S. coal, which has a lower heat output but is also cheaper. It depends on Australia for 70% of coal supply but started to diversify the source. 3 tabs.

  8. Are internet prices sticky?

    OpenAIRE

    Lünnemann, Patrick; Wintr, Ladislav

    2006-01-01

    This paper studies the behaviour of Internet prices. It compares price rigidities on the Internet and in traditional brick-and-mortar stores and provides a cross-country perspective. The data set covers a broad range of items typically sold over the Internet. It includes more than 5 million daily price quotes downloaded from price comparison web sites in France, Germany, Italy, the UK and the US. The following results emerge from our analysis. First, and contrary to the recent findings for co...

  9. Regulation of Pharmaceutical Prices

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Méndez, Susan J.; Rønde, Thomas

    2014-01-01

    Reference prices constitute a main determinant of patient health care reimbursement in many countries. We study the effects of a change from an "external" (based on a basket of prices in other countries) to an "internal" (based on comparable domestic products) reference price system. We find...... that while our estimated consumer compensating variation is small, the reform led to substantial reductions in list and reference prices as well as co-payments, and to sizeable decreases in overall producer revenues, health care expenditures, and co-payments. These effects differ markedly between branded...

  10. Regulation of Pharmaceutical Prices

    DEFF Research Database (Denmark)

    Kaiser, Ulrich; Méndez, Susan J.; Rønde, Thomas

    Reference prices constitute a main determinant of patient health care reimbursement in many countries. We study the effects of a change from an "external" (based on a basket of prices in other countries) to an "internal" (based on comparable domestic products) reference price system. We find...... that while our estimated consumer compensating variation is small, the reform led to substantial reductions in list and reference prices as well as co-payments, and to sizeable decreases in overall producer revenues, health care expenditures, and co-payments. These effects differ markedly between branded...

  11. Alternative pricing methodologies

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    With the increased interest in competitive market forces and growing recognition of the deficiencies in current practices, FERC and others are exploring alternatives to embedded cost pricing. A number of these alternatives are discussed in this chapter. Marketplace pricing, discussed briefly here, is the subject of the next chapter. Obviously, the pricing formula may combine several of these methodologies. One utility of which the authors are aware is seeking a price equal to the sum of embedded costs, opportunity costs, line losses, value of service, FERC's percentage adder formula and a contract service charge

  12. Stand, Harvest, and Equipment Interactions in Simulated Harvesting Prescriptions

    Science.gov (United States)

    Jingxin Wang; W. Dale Greene; Bryce J. Stokes

    1998-01-01

    We evaluated potential interactions of stand type, harvesting method, and equipment in an experiment using interactive simulation. We examined three felling methods (chain saw, feller-buncher, harvester) and two extraction methods (grapple skidder and forwarder) performing clearcuts, sheltenvood cuts, and single-tree selection cuts in both an uneven-aged natural stand...

  13. In vitro propagation of an endangered medicinal timber species ...

    African Journals Online (AJOL)

    The over exploitation of African mahogany in tropical forest has threatened the genetic base of this useful timber and medicinal tree species and as such, an experiment was conducted on the in vitro culture of Khaya grandifoliola, an endangered tree species commonly found in the high forest zones of West Africa to explore ...

  14. 75 FR 63419 - Surety Bond Guarantee Program; Timber Sales

    Science.gov (United States)

    2010-10-15

    ... with the contract terms. 36 CFR 223.35. Generally, the Performance Bond, as defined in 13 CFR 115.10, ensures that the Principal, as defined in 13 CFR 115.10, complies with all contract terms and conditions... timber sale contracts awarded by the Federal Government or other public or private landowners. DATES...

  15. Projecting southern timber supply for multiple products by subregion

    Science.gov (United States)

    Robert C. Abt; Frederick W. Cubbage; Karen L. Abt

    2009-01-01

    While timber supply modeling has been of importance in the wood-producing regions of the United States for decades, it is only more recently that the technology and data have allowed disaggregation of supply and demand to substate regions, including product specific breakdowns and endogenous land use and plantation changes. Using southwide data and an economic supply...

  16. An Ethnobotanical Survey on Fuel Wood and Timber plant Species ...

    African Journals Online (AJOL)

    Yomi

    2011-12-19

    Dec 19, 2011 ... 3Department of Botany, Post Graduate College Abbottabad, Pakistan. Accepted 17 March, 2011. A survey was conducted to explore the fuel wood species and timber producing species of Kaghan valleys, Pakistan. Consumption pattern and impact on the forest resources were also taken into consideration.

  17. Essays on the economics of British Columbian timber policy

    NARCIS (Netherlands)

    Niquidet, Kurt

    2007-01-01

    This thesis examines the process of institutional change in British Columbia’s timber sector. It is composed of a series of essays which highlight the underlying political and economic factors that have shaped past and current reforms. Taking center stage in the analysis, are the resource rents

  18. Forest ecosystem services: Provisioning of non-timber forest products

    Science.gov (United States)

    James L. Chamberlain; Gregory E. Frey; C. Denise Ingram; Michael G. Jacobson; Cara Meghan Starbuck Downes

    2017-01-01

    The purpose of this chapter is to describe approaches to calculate a conservative and defensible estimate of the marginal value of forests for non-timber forest products (NTFPs). 'Provisioning" is one of four categories of benefits, or services that ecosystems provide to humans and was described by the Millennium Ecosystem Assessment as 'products...

  19. Pennsylvania hardwood timber bridges : field performance after 10 years

    Science.gov (United States)

    James P. Wacker; Carlito Calil

    2004-01-01

    Several hardwood demonstration timber bridges were built by the Pennsylvania Department of Transportation in the early nineteen nineties. These bridge superstructures are of the recently developed stress-laminated deck design-type using Red Oak lumber laminations that were pressure-treated with creosote preservatives. This paper will describe the data acquisition...

  20. Timber resource of Michigan's Southern Lower Peninsula Unit, 1980.

    Science.gov (United States)

    Jerold T. Hahn

    1982-01-01

    The fourth inventory of the timber resource of Michigan's Southern Lower Peninsula Survey Unit shows a 12% decline in commercial forest area and a 26% gain in growing-stock volume between 1966 and 1980. Presented are highlights and statistics on area, volume, growth, mortality, removals, utilization, and biomass.