Wood Products Research Papers - Academia.edu (original) (raw)

At present, the production of wood composites mainly relies on the petrochemical-based and formaldehyde-based adhesives such as phenol-formaldehyde (PF) resins and urea-formaldehyde (UF) resins, which are non-renewable and therefore... more

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- Wood Products, Forestry Sciences, Sodium Hydroxide, Aqueous Solution

The viability of the many civilisations of Europe has depended, to a very large extent, on an adequate supply of wood. In the Ancient World, this supply was secured through the exploitation of forest reserves, the conquest of new territories and, when these opportunities no longer presented themselves, through the conservation of diminishing resources. Ultimately, civilisations collapsed because of the shortage of wood. Although some silvicultural techniques were known in the pre-Christian era, the scienti®c management of forests was not widely practised until the late 18th century. It is argued that the controlled exploitation of`nature', on sustained yield principles, only became possible when men came to view the forest, not as a nuisance, an Arcadia or a pagan horror, but as a centre of wood production, a biological factory.

By allowing the estimation of forest structural and biophysical characteristics at different temporal and spatial scales, remote sensing may contribute to our understanding and monitoring of planted forests. Here, we studied 9-year time-series of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on a network of 16 stands in fast-growing Eucalyptus plantations in São Paulo State, Brazil. We aimed to examine the relationships between NDVI time-series spanning entire rotations and stand structural characteristics (volume, dominant height, mean annual increment) in these simple forest ecosystems. Our second objective was to examine spatial and temporal variations of light use efficiency for wood production, by comparing time-series of Absorbed Photosynthetically Active Radiation (APAR) with inventory data.

- by Daniel Epron
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- Remote Sensing, Production, Structure, Time Series

The toxic effects of selected Malaysian timbers (Madhuca utilis, Anisoptera laevis and Endospermum malaccense) heartwood extracts were studied with the aim to determine and understanding the function of wood extracts as a natural protection against termite. The results show that no-choice experiments revealed toxic properties of all investigated extracts by the contact against Coptotermes gestroi and Coptotermes curvignathus. However, high termite mortality was only achieved with Madhuca utilis extracts and methanol solvents.

- by Roszaini Kadir
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- Biology, Wood Science, Timber, Wood Engineering

The pinyon/juniper woodlands of the Great Basin were a vital source of structural wood and energy products for the mining industry from the 1860's to the 1930's. Pinyon and juniper were cut extensively for fuel wood and for the prod uction of charcoal, the only available fuel or energy source for the smelters of central Nevada. Firewood and fence post for ranches wexe also important uses of pinyon and juniper. Deforestation by cutting, promiscuous burning continued unabated until the 1920's and 1930's, when fossil fuels, substitute types of structural wood, and fire control combined to decrease disturbance in this vegetation type.

- by Toni Ergi
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- Nineteenth Century, Wood Products, Artemisia, Species Composition

... In the late winter, when the stresses of frost, drought and photo-inhibition interact and the stability of the hardiness stage is violated by large temperature amplitudes and fast changes, LP exhibits more visual damage ( Karlman,... more

Effect of zeolite content on the physical, mechanical and thermal properties of wood plastic composites was investigated in this study. To meet this objective, pine wood flour (0, 10, 20, 30, 40, 50 wt%) with compatibilizing agent, zeolite (0, 10, 20, 30, 40, 50 wt%), and polypropylene were compounded in a twin screw co-rotating extruder. The mass ratio of the wood flour to polypropylene was 50/50 (w/w) in all compounds. Test specimens were produced using injection molding machine from the pellets. Physical and mechanical, and thermal (Thermogravimetry Analysis/Differential Scanning Calorimetry) properties of the wood plastic composites were determined. The water absorption and thickness swelling properties of wood plastic composites improved with increasing zeolite content. The flexural and tensile properties of the wood plastic composites decreased with increasing zeolite content. All the wood plastic composites provided the values of flexural strength (58.4–72.9 MPa) and flexural modulus (2718-5024 MPa) that were well over the requirement by the standard specified in ASTM D 6662. The mass loss rates values of wood plastic composites increased with increasing zeolite contents. The Differential Scanning Calorimetry analysis showed that the melt crystallization enthalpies and degree of crystallization of wood plastic composites decreased with increasing zeolite content. The decrease in the Tc and Xc indicated that zeolite was the poor nucleating agent for the wood plastic composites.

- by Maderas. Ciencia y Tecnologia
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- Wood Plastic Composite, Timber, Wood Engineering, Wood Products

Secondary manufacturers in the forest products industry face a complex production planning process. Linear programming (LP)-based applications have addressed this production planning issue. However, most models have been developed for a specific plant configuration and cannot readily be applied to others. A relational database approach was used to create an integrated linear programming-based decision support system that can be used to analyze production planning issues in a wide variety of secondary wood product manufacturers. The flexibility of the resultant system indicated the potential to analyze production strategies in the highly dynamic environment characteristic of secondary manufacturers. D

... of C sequestration and timber production (eg, [22] , [Kurz et al., 2002] , [Backéus et al., 2005] and [Gusev and Nasonova, 2007] ), simulation of effects of management and climate on C sequestration by forests (eg, [Kurz and Apps,... more

- by Cecilia Bustos
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- Wood Science, Prefabricated wood, Wood mechanics, Wood Engineering

Carbon storage in aboveground tree biomass and soil organic matter (in depth of A layer development i.e., up to 20 cm) was studied in 22-32 year-old post-mining sites in the northwest of the Czech Republic. Four replicated sites afforested with different tree species (spruce, pine, larch, oak, lime or alder) were compared with sites left to natural regeneration which were dominated by aspen, birch and willow. No topsoil was applied at the sites; hence carbon accumulation resulted from in situ soil development on alkaline tertiary clays that were dumped on the heaps. In aboveground tree biomass, carbon storage ranged from 17.0 ± 5.9 (mean ± SEM) to 67.6 ± 5.9 t ha -1 and the rate of C accumulation increased from 0.60 ± 0.09 to 2.31 ± 0.23 t ha -1year -1 (natural regeneration \ pine \ spruce \ oak \ lime \ alder \ larch). Carbon storage in soil organic matter varied from 4.5 ± 3.7 to 38.0 ± 7.1 t ha -1 and the rate of C accumulation in soil organic matter increased from 0.15 ± 0.05 to 1.28 ± 0.34 t ha -1 year -1 at sites in the order: natural regeneration \ spruce \ pine, oak \ larch \ alder \ lime. Carbon storage in the soil was positively correlated with aboveground tree biomass. Soil carbon was equivalent to 98.1% of the carbon found in aboveground tree biomass at lime dominated sites, but only 21.8% at sites with natural regeneration. No significant correlation was found between C storage in soil and aboveground litter input. Total soil carbon storage was correlated positively and significantly with earthworm density, and occurrence of earthworm cast in topsoil, which indicated that bioturbation could play an important role in soil carbon storage. Hence, not only restoring of wood production, but also restoring of soil community is critical for C storage in soil and whole ecosystem.

- by Emil Cienciala
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- Geochemistry, Biogeochemistry, Regeneration, Carbon

Carbon accounting Estimation method Greenhouse gas emission inventories Harvested wood products Production approach Stock-change approach Uncertainty analysis a b s t r a c t There is a great diversity of methods for estimating carbon storage in harvested wood products (HWP) and, therefore, it is extremely important to agree internationally on the methods to be used in national greenhouse gas inventories. This study compares three methods for estimating carbon accumulation in HWP: the method suggested by Winjum et al. (Winjum method), the tier 2 method proposed by the IPCC Good Practice Guidance for Land Use, Land-Use Change and Forestry (GPG LULUCF) (GPG tier 2 method) and a method consistent with GPG LULUCF tier 3 methods (GPG tier 3 method). Carbon accumulation in HWP was estimated for Portugal under three accounting approaches: stock-change, production and atmospheric-flow. The uncertainty in the estimates was also evaluated using Monte Carlo simulation. The estimates of carbon accumulation in HWP obtained with the Winjum method differed substantially from the estimates obtained with the other methods, because this method tends to overestimate carbon accumulation with the stock-change and the production approaches and tends to underestimate carbon accumulation with the atmospheric-flow approach. The estimates of carbon accumulation provided by the GPG methods were similar, but the GPG tier 3 method reported the lowest uncertainties. For the GPG methods, the atmospheric-flow approach produced the largest estimates of carbon accumulation, followed by the production approach and the stock-change approach, by this order. A sensitivity analysis showed that using the ''best'' available data on production and trade of HWP produces larger estimates of carbon accumulation than using data from the Food and Agriculture Organization.

- by Luís Arroja
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- Engineering, Technology, Monte Carlo Simulation, Sensitivity Analysis

The paper describes the Version 2 of the CO2FIX (CO2FIX V.2) model, a user-friendly tool for dynamically estimating the carbon sequestration potential of forest management, agroforesty and afforestation projects. CO2FIX V.2 is a multi-cohort ecosystem-level model based on carbon accounting of forest stands, including forest biomass, soils and products. Carbon stored in living biomass is estimated with a forest cohort model that allows for competition, natural mortality, logging, and mortality due to logging damage. Soil carbon is modeled using five stock pools, three for litter and two for humus. The dynamics of carbon stored in wood products is simulated with a set of pools for short-, medium-and long-lived products, and includes processing efficiency, re-use of by-products, recycling, and disposal forms. The CO2FIX V.2 model estimates total carbon balance of alternative management regimes in both even and uneven-aged forests, and thus has a wide applicability for both temperate and tropical conditions. Results for the model testing and validation in selected temperate and tropical forest management systems are presented and discussed.

- by T. Karjalainen and +1
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- Carbon Sequestration, Multidisciplinary, Ecological Modelling, Forest Management

This study analyses forest cooperative's participation in forestry in Turkey. The study was carried out with 71 forest cooperatives in the Kastamonu province, located in the Western Black Sea Region. By using a principal component... more

Removing atmospheric carbon (C) and storing it in the terrestrial biosphere is one of the options, which have been proposed to compensate greenhouse gas (GHG) emissions. Agricultural lands are believed to be a major potential sink and could absorb large quantities of C if trees are reintroduced to these systems and judiciously managed together with crops and/or animals. Thus, the importance of agroforestry as a land-use system is receiving wider recognition not only in terms of agricultural sustainability but also in issues related to climate change. The objective of this paper was to analyse C storage data in some tropical agroforestry systems and to discuss the role they can play in reducing the concentration of CO 2 in the atmosphere. The C sequestration potential of agroforestry systems is estimated between 12 and 228 Mg ha −1 with a median value of 95 Mg ha −1 . Therefore, based on the earth's area that is suitable for the practice (585-1215 × 10 6 ha), 1.1-2.2 Pg C could be stored in the terrestrial ecosystems over the next 50 years. Long rotation systems such as agroforests, homegardens and boundary plantings can sequester sizeable quantities of C in plant biomass and in long-lasting wood products. Soil C sequestration constitutes another realistic option achievable in many agroforestry systems. In conclusion, the potential of agroforestry for CO 2 mitigation is well recognised. However, there are a number of shortcomings that need to be emphasised. These include the uncertainties related to future shifts in global climate, land-use and land cover, the poor performance of trees and crops on substandard soils and dry environments, pests and diseases such as nematodes. In addition, more efforts are needed to improve methods for estimating C stocks and trace gas balances such as nitrous oxide (N 2 O) and methane (CH 4 ) to determine net benefits of agroforestry on the atmosphere.

- by Rajagopal Vadivel
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- Climate Change, Carbon Sequestration, Global Warming, Land use and land cover

The productivity of forest sites has been indirectly determined with solo wood production objective in forest management. Forest site productivity should, however, be determined directly in order to implement ecosystem based multipurpose forest management philosophy. This article tackles the problem in distinguishing and mapping forest sites using both direct method and indirect method in Genya Mountain located in central of Artvin State Forest Enterprise. About 112 sample plots were designed and distributed over the area. In each sample plot, soil samples were collected and the classical timber inventory measurements were taken. According to direct method, Soil Moisture Regime (SMR) method is preferred due to a water deficiency in the study area. Water holding capacity was used as an essential criterion for the classification of the forest site. Forest site classifications were assigned regarding the physiographic factors such as landform, aspect, and slope. Five different forest sites classes; dry, moderate fresh, fresh, humid and hygric were determined. According to direct method, the guiding curve was used to generate anamorphic site index (SI) equations and three site index classes; good (SI=I-II), medium (SI=III) and low (SI=IV-V) were determined. Some important differences between the methods were realized. The forest sites determined with site index estimation method indicate that site index I and II is 505.99 ha, III 1095.79 ha and IV and V 992.95 ha, whereas forest sites determined with direct method related to dry site of 937.58 ha, moderate fresh site of 931.90 ha, fresh site of 1,797.71 ha, humid site of 80.48 ha and hygric site of 356.55 ha. The forest site maps of both methods were created using GIS functions. The forest sites of open and degraded areas should be determined according to direct method.

- by Ali Kadiogullari
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- Turkey, Environmental Monitoring, Multidisciplinary, Site Productivity

The oscillatory behavior in the mature phase of some technologies'diffusion-related S curves are investigated, specifically with regard to the influences that other technologies can have on the oscillations. The notion of mortality indicators is raised, that is, whether such behavior is a signal that the mature technology is under attack from an emerging technology. The case of structural panels in the wood products industry is considered as an example, and an updated forecast of the substitution of oriented strand board for plywood is made. It is concluded that factors such as macroeconomic business cycles are primarily responsible for the oscillations in plywood's S-curve, although it is argued that an emerging technology can also contribute to perturbations in a mature technology's S-curve. Two possible alternative explanations for the oscillatory behavior are also discussed, a previously proposed chaos formulation, and a mathematical model based on modified Lotka-Volterra equations. This model shows that the oscillatory behavior in mature technologies' S-curves can also result from symbiotic interaction between two technologies under certain circumstances.

- by James Utterback
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- Economics, Technology, Lotka Volterra, Oriented Strand Board

The heterogeneity of characteristics observed in the pith-bark direction within a log causes sawn pieces of wood have different behaviors during water removal. Understanding these differences is important for the industry regarding the possibility of classification of the lumber into juvenile wood and mature wood, facilitating the drying in separate loads. Thus, this study aimed to evaluate the behavior of juvenile and mature wood samples of Eucalyptus saligna when subjected to drastic drying. In order to do this, test specimens were submitted to drastic drying at 100°C to obtain the drying times, drying rates and dimensions of end checks. These data were applied in equations to obtain the parameters initial temperature, final temperature and drying potential, used in the elaboration of drying schedules. In juvenile wood we observed that the basic density was lower and the initial moisture content was higher. Mature wood showed a lower drying rate. Drying schedules were developed separately for juvenile and mature wood, the drying schedule for the latter considered milder than the drying schedule developed for juvenile wood.

- by José Reinaldo Moreira Silva
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- Wood Science, Timber, Wood Engineering, Lumber industry

The emission of volatile organic compounds (VOC) from wood and wood products are important in evaluating the impact on the indoor environment from different materials. The results from analyses of emissions from nine different wood species are presented in this article. The measurements were made with Field and Laboratory Emission Cell (FLEe) and with Head-Space (HS) analyses and the results from the different methods are discussed. The main emissions are terpenes from softwood and acetic acid from hardwood.

- by Paulien Herder
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- Building, Wood Products, European, Forestry Sciences
- by Francesca Gambineri and +1
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- Life Cycle Assessment, Waste Management, Legislation, Case Study

The coastal areas of Bangladesh have a high cyclone frequency, and the protection from cyclone damage afforded by the natural mangrove forests of the Sundarbans, led the Forest Department in 1966 to initiate a mangrove afforestation program. These initial plantings proved highly successful in protecting and stabilizing coastal areas, and led to a largescale mangrove afforestation initiative. To date, approximately 120,000 ha of mangroves have been planted. Nursery and planting techniques have been developed for the major species, while additional species are still being investigated. As a result of the extensive monospecific plantations, however, outbreaks of two major insect pest species have been observed.

- by N. A Siddiqi and +1
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- Earth Sciences, Environmental Science, Environmental Sciences, Wood Products

Cork oak stands are a part of the agroforestry ecosystem in Portugal, characterized by a low crown cover from cork oak trees, managed towards cork production, and sometimes in combination with grazing. In recent years, European Union policies gave impetus to a large area of new cork oak plantations, which have been established mainly for cork production purposes, and consequently with higher stand density than traditional agroforestry systems. These plantations are important not only for cork production but also for the carbon sequestered by these slow growing forests that won't be harvested for wood production. Thinning operations will be needed to avoid excessive inter-tree competition and wood extracted from these thinning may also provide income for the owners. In the present study, carbon sequestered and wood volumes resulting from thinning were estimated for the next 70 years. Three scenarios of different annual afforestation rates and different site indexes were tested. The resulting values for the considered scenarios show that, if the plantation rates are maintained, new cork oak plantations will have an important contribution to the Portuguese commitments to providing CO 2 offsets under the Kyoto protocol. Additionally, due to the increasing values of initial density in new cork plantations, cork oak forests will produce a significant volume of wood that may become an important contribution to the landowners' income.

- by joana paulo and +1
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- European Union, Carbon Sequestration, Applied Economics, Site index

This review critically examines the role of boron (B) in forests in view of recent findings on B nutrition and the continuing occurrence of B deficiency. Many perceptions about the role of B in plants and its uptake and mobility have been altered since the last review on B in forest trees in 1990. Now there is evidence for a fundamental role of B in the formation of the pectic structure in primary cell walls in plants, and further roles in membrane function are being explored. In plants, channel-mediated B uptake, active B uptake and B uptake by mycorrhizas have been shown, B transporters have been identified, and B retranslocation has been shown. We explore these findings and their consequences on forest trees and on ecosystems that they dominate. Particular emphasis is placed on B retranslocation and B in mycorrhizal symbiosis, given their importance in trees.

- by Bernard Dell
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- Management, Forestry, Symbiosis, Forest Ecology And Management

Low-cost and simple technologies are needed to reduce watershed export of excess nitrogen to sensitive aquatic ecosystems. Denitrifying bioreactors are an approach where solid carbon substrates are added into the flow path of contaminated water. These carbon (C) substrates (often fragmented wood-products) act as a C and energy source to support denitrification; the conversion of nitrate (NO 3 − ) to nitrogen gases. Here, we summarize the different designs of denitrifying bioreactors that use a solid C substrate, their hydrological connections, effectiveness, and factors that limit their performance. The main denitrifying bioreactors are: denitrification walls (intercepting shallow groundwater), denitrifying beds (intercepting concentrated discharges) and denitrifying layers (intercepting soil leachate). Both denitrifcation walls and beds have proven successful in appropriate field settings with NO 3 − removal rates generally ranging from 0.01 to 3.6 g N m −3 day −1 for walls and 2-22 g N m −3 day −1 for beds, with the lower rates often associated with nitrate-limitations. Nitrate removal is also limited by the rate of C supply from degrading substrate and removal is operationally zero-order with respect to NO 3 − concentration primarily because the inputs of NO 3 − into studied bioreactors have been generally high. In bioreactors where NO 3 − is not fully depleted, removal rates generally increase with increasing temperature. Nitrate removal has been supported for up to 15 years without further maintenance or C supplementation because wood chips degrade sufficiently slowly under anoxic conditions. There have been few field-based comparisons of alternative C substrates to increase NO 3 − removal rates but laboratory trials suggest that some alternatives could support greater rates of NO 3 − removal (e.g., corn cobs and wheat straw). Denitrifying bioreactors may have a number of adverse effects, such as production of nitrous oxide and leaching of dissolved organic matter (usually only for the first few months after construction and start-up). The relatively small amount of field data suggests that these problems can be adequately managed or minimized. An initial cost/benefit analysis demonstrates that denitrifying bioreactors are cost effective and complementary to other agricultural management practices aimed at decreasing nitrogen loads to surface waters. We conclude with recommendations for further research to enhance performance of denitrifying bioreactors. (L.A. Schipper). trated discharges in agricultural systems occur through under-field tile drainage and ditches while diffuse sources are typically through the discharge of shallow groundwater to surface waters. Nitrogen that is captured in biomass passes through the food chain and ends up in wastewater streams, which are ultimately discharged to surface waters.

- by louis Schipper
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- Engineering, Ecological Engineering, Earth Sciences, Aquatic Ecosystem

This paper evaluates the results of contamination of residents and residential homes located in close proximity to a Wood Treatment Plant. The plant has produced treated wood products continuously since 1904. The principle chemicals used to treat the wood, which is primarily used for railroad ties (oblong objects laid perpendicular to the rails to act as a base for the tracks), are creosote and pentachlorophenol. For a number of years, the plant burned treated waste wood products containing creosote and pentachlorophenol.

- by Raphael Warshaw
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- Housing, Rivers, Risk assessment, Multidisciplinary

Este es un estudio exploratorio para dar uso a la madera de Eucalyptus urophylla para la elaboración de tableros aglomerados de partículas. Por lo tanto, los objetivos fueron determinar sus propiedades físico-mecánicas y evaluar los resultados bajo norma Alemana y Venezolana. La absorción de agua promedio a 2 y 24 horas de los tableros para la densidad real de 731 kg/m3 no cumplió con lo estipulado en las normas, para el caso de los tableros de densidad real 831 kg/m3 si cumplió con la norma. La variación del espesor (hinchamiento) promedio por inmersión en agua a 2 horas para los tableros con densidad de 731 kg/m3 no cumplió con lo exigido en ambas normas, pero si cumplieron los requerimientos para 24 horas. Para el caso de los tableros con densidad de 838 kg/m3 la variación de espesor a 2 y 24 horas cumplió con las normas. Respecto de las propiedades mecánicas, tanto el módulo de ruptura en flexión estática como la tensión perpendicular (adhesión interna) para ambos niveles de densidad superaron el valor mínimo aceptado en las normas, demostrando que las partículas de madera de Eucalyptus urophylla presentan buenas características tecnológicas para la fabricación de tableros de partículas de densidad media.

- by Maderas. Ciencia y Tecnologia
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- Wood Science, Timber, Lumber industry, Wood Products

Molecular genetic markers have numerous potential applications in environmental forensics if DNA can be isolated from 'difficult' non-human biological material such as hairs, feathers, or wood. The identification of the origin of wood is particularly important in order to identify illegally harvested and traded timber and wood products. We describe success rates of DNA isolation from wood based on a simple, previously published extraction protocol. The protocol was used to isolate DNA from a total of 406 wood samples, mainly of the important tropical tree family Dipterocarpaceae. The reliability of the extraction method was confirmed by comparing fragment sizes and sequences after isolation of DNA from leaves and wood of the same trees. We observed the success of amplification of chloroplast DNA (cpDNA) fragments of different lengths by means of PCR, investigated key factors influencing PCR, and conducted inhibitor tests for a subset of the samples. The average rate of succe...

- by Yanti Rachmayanti
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- Forensic Science, Molecular Genetics, Biological Sciences, Tropical trees

This reports presents a manual of the CO2FIX V 2.0 model. CO2FIX V 2.0 is a simple bookkeeping model that converts volumetric net annual increment data (and additional parameters) to annual carbon stocks and fluxes of the forest ecosystem-soil-wood products chain. It calculates on the hectare scale with time steps of one year. This Version 2.0 is a hectare scale

- by Markku Kanninen
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- Carbon Sequestration, End of life, Wood Products, Selective Logging

In the present study, a spectrophotometric method for the determination of formaldehyde by using chromotropic acid was devised, in which the use of potentially hazardous and corrosive concentrated sulfuric acid was eliminated and advantageously replaced by a mixture of H PO and H O . The reaction between formaldehyde and chromotropic acid (CA) in a concentrated 3 4 2 2 phosphoric acid medium was accelerate by irradiating the mixture with microwave energy for 35 s (1100 W), producing a violetred compound (l s570 nm). Beer's Law is obeyed in a concentration range of 0.8-4.8 mg l of formaldehyde with a good y1 max correlation coefficient (rs0.9968). The proposed method was applied in the analysis of formaldehyde in commercial disinfectants. Recoveries were within 98.0-100.4%, with standard deviations ranging from 0.03 to 0.13%. ᮊ

- by Linda Li
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- Chemical Engineering, Analytical Chemistry, Uv Spectrophotometer, Standard Deviation

Shade trees reduce the stress of coffee (Coffea spp.) and cacao (Theobroma cacao) by ameliorating adverse climatic conditions and nutritional imbalances, but they may also compete for growth resources. For example, shade trees buffer high and low temperature extremes by as much as 5 °C and can produce up to 14 Mg ha-1 yr-1 of litterfall and pruning residues, containing up to 340 kg N ha-1 yr-1. However, N 2 fixation by leguminous shade trees grown at a density of 100 to 300 trees ha-1 may not exceed 60 kg N ha-1 yr-1. Shade tree selection and management are potentially important tools for integrated pest management because increased shade may increase the incidence of some commercially important pests and diseases (such as Phythphora palmivora and Mycena citricolor) and decrease the incidence of others (such as Colletotrichum gloeosporioides and Cercospora coffeicola). In Central America, merchantable timber production from commercially important shade tree species, such as Cordia alliodora, is in the range of 4-6 m 3 ha-1 yr-1. The relative importance and overall effect of the different interactions between shade trees and coffee/cacao are dependent upon site conditions (soil/climate), component selection (species/varieties/provenances), belowground and aboveground characteristics of the trees and crops, and management practices. On optimal sites, coffee can be grown without shade using high agrochemical inputs. However, economic evaluations, which include off-site impacts such as ground water contamination, are needed to judge the desirability of this approach. Moreover, standard silvicultural practices for closed plantations need to be adapted for open-grown trees within coffee/cacao plantations.

- by Eduardo Somarriba
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- Geography, Integrated Pest Management, Ground Water, Wood Products

The effects of wood-ash fertilisation on tree stands, soil characteristics and ground vegetation were studied on a drained pine mire in Finland (64°51′N, 26°04′E, 62 m a.s.l.). The original site type was a treeless, mesotrophic Sphagnum papillosum fen. The site was drained in 1933 and the wood-ash fertilisation experiment was started in 1947. The treatments were: (i) unfertilised, (ii) wood-ash 8 t ha−1, and (iii) wood-ash 16 t ha−1.Drainage and ash application had radical and long-lasting consequences on the biological activity on the site and the vegetation compartments studied. The understorey vegetation had been profoundly affected by the ash with almost complete transformation of the species and other life forms. Even 50 years after the ash treatment the changes in vegetation/site type and the tree stand were clearly visible. On the unfertilised plot, the biomass of ground vegetation consisted mostly of mosses and dwarf shrubs, but on the ash-treated plots it consisted mostly of herbs and grasses typical of upland forests.Ash treatment had promoted stem volume growth of Scots pine (Pinus sylvestris L.) substantially and for a long time. The total wood production on the ash plots during 1947–1994 was 13 and 17 times over that of the control plot. Unfertilised pine trees suffered from P and K deficiency throughout the study period. The concentrations of some plant nutrients (P, K) decreased during the past years on Ash8. No nutrient shortage afflicting the tree stand was observed on Ash16 during the study period.Ash application has also led to increased concentration of nutrients in the peat. A sizeable proportion of the mineral nutrients applied were still in the 0–20 cm peat layer. On the ash-treated plots the amount of soil nitrogen (0–20 cm) was 18 and 29 times and the amount of soil phosphorus 9 and 13 times over the amount bound by the tree stand and the ground vegetation (Ash8 and Ash16, respectively). The stock of potassium was generally small in the surface peat—only 60–90% of the amount of potassium bound in the tree stand and the ground vegetation.It was concluded that wood-ash had powerfully influenced the biological processes in surface peat. The decomposition of cellulose was significantly accelerated by both ash treatments. Ash fertilisation also increased the emissions of CO2. The intensified decomposition rate in the litter, vegetation and peat explained to a large extent the accelerated growth of the Scots pine stands studied.

- by Mikko Moilanen
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- Nutrition, Decomposition, Forest Ecology And Management, Forest Ecology

Terrestrial ecosystems provide a number of vital services for people and society, such as biodiversity, food, fibre, water resources, carbon sequestration, and recreation. The future capability of ecosystems to provide these services is determined by changes in socio-economic characteristics, land use, biodiversity, atmospheric composition and climate. Most published impact assessments do not address the vulnerability of the human-environment system under such environmental change. They cannot answer important multidisciplinary policy relevant questions such as: which are the main regions or sectors that are vulnerable to global change? How do the vulnerabilities of two regions compare? Which scenario is the least, or most, harmful for a given region or sector?

- by Rik Leemans
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- Socioeconomics, Forestry, Climate Change, Natural Resources

Tropical forests in countries like the Philippines are important sources and sinks of carbon (C). The paper analyzes the contribution of Philippine forests in climate change mitigation. Since the 1500s, deforestation of 20.9 M ha (10 6 ha) of Philippine forests contributed 3.7 Pg (10 15 g) of C to the atmosphere of which 2.6 Pg were released this century. At present, forest land uses store 1091 Tg (10 12 g) of C and sequester 30.5 Tg C/yr while releasing 11.4 Tg C/yr through deforestation and harvesting. In the year 2015, it is expected that the total C storage will decline by 8% (1005 Tg) and total rate of C sequestration will increase by 17% (35.5 Tg/yr). This trend is due to the decline in natural forest area accompanied by an increase in tree plantation area. We have shown that uncertainty in national C estimates still exists because they are readily affected by the source of biomass and C density data. Philippine forests can act as C sink by: conserving existing C sinks, expanding C stocks, and substituting wood products for fossil fuels. Here we analyze the possible implications of the provisions of the Kyoto Protocol to Philippine forests. Finally, we present current research and development efforts on tropical forests and climate change in the Philippines to improve assessments of their role in the nations C budgets.

- by Rodel Lasco
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- Climate Change, Land Use Change, Climate Change Mitigation, Fossil Fuels

The WoodMark Quality System, a new quality assurance program for the Canadian value-added wood products sector, was launched in 1999. This represented the culmination of a five-year investigation of industry needs, standards development, and potential benefits, as they relate to implementing a third-party quality assurance system for the Canadian value-added industry. The WoodMark Quality System is an industry-specific system dedicated

- by Thomas Maness
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- Quality Assurance, Raw materials, Process Improvement, Building

- by Pravesh Kumar
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- Climate Change, Carbon Sequestration, Global Warming, Land use and land cover

This study compiles and summarizes the existing knowledge about observed and projected impacts of climate change on forests in Europe. Forests will have to adapt not only to changes in mean climate variables but also to increased variability with greater risk of extreme weather events, such as prolonged drought, storms and floods. Sensitivity, potential impacts, adaptive capacity, and vulnerability to climate change are reviewed for European forests. The most important potential impacts of climate change on forest goods and services are summarized for the Boreal, Temperate Oceanic, Temperate Continental, Mediterranean, and mountainous regions. Especially in northern and western Europe the increasing atmospheric CO 2 content and warmer temperatures are expected to result in positive effects on forest growth and wood production, at least in the short-medium term. On the other hand, increasing drought and disturbance risks will cause adverse effects. These negative impacts are very likely to outweigh positive trends in southern and eastern Europe. From west to east, the drought risk increases. In the Mediterranean regions productivity is expected to decline due to strongly increased droughts and fire risks.

- by Jordi Garcia-gonzalo and +2
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- Forestry, Western Europe, Eastern Europe, Climate Change

Eucalyptus (family Myrtaceae), an Australian native, represented by around 700 species is a genus of tall, evergreen and magnificent trees cultivated world over for its oil, gum, pulp, timber, medicine and aesthetic value. Among the various wood and non-wood products, essential oil found in its foliage is the most important one and finds extensive use in food, perfumery and pharmaceutical industry. In addition, the oil possesses a wide spectrum of biological activity including anti-microbial, fungicidal, insecticidal/insect repellent, herbicidal, acaricidal and nematicidal. The present paper discusses this environmentally benign pest control using eucalyptus oils against bacteria, fungi, insects, nematodes, weeds and mites. The use of eucalyptus oil as a natural pesticide is of immense significance in view of the environmental and toxicological implications of the indiscriminate use of synthetic pesticides and overcoming/reducing the problem of increasing pest resistance.

Low permeability of many wood species due to their anatomical properties causes problems during timber drying as well as impregnating with preservatives and resins. Microwave (MW) treatment influences heartwood permeability and improves preservative uptake and distribution. In the present study, microwave treatment of chir pine (Pinus roxburghii) wood was done at 2,45 GHz frequency at different level of intensity and radiation time. The gas permeability of chir pine wood was measured in an in-house built apparatus. Preservative uptake was tested using acid copper chromate (ACC) preservative by a dipping process. The effect of radiation intensity and time on preservative uptake and air permeability were studied. The results revealed remarkable increase in longitudinal wood air permeability and preservative uptake with the increase of intensity and time of treatment. The results indicate that this technology can be tested and applied on pilot scale for application in wood preservation industry.

- by Maderas. Ciencia y Tecnologia
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- Wood Science, Timber, Wood Engineering, Lumber industry

Cross-linked polyvinyl acetate (PVAc) adhesive and thin veneers of three low density wood species, namely silver maple, yellow poplar and aspen, were used to produce LVL engineered wood products using different press durations. Density, water absorption, thickness swelling, flexural strength and surface hardness were evaluated. Internal bond strength, tensile shear and block shear strengths were tested in dry, accelerated (boiling and dry) and cyclic (wet and dry) conditions. LVL made using cross-linked polyvinyl acetate and silver maple with a platen temperature of 38 • C for 5 minutes exhibited the best properties. LVL of silver maple veneers showed improved properties as compared to yellow poplar and aspen. Silver maple can be used suitably in laminated veneer flooring.

- by Donatien Pascal Kamdem
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- Building, Wood Products, Flexural Strength, Water Absorption

Rubber trees were introduced into the Malay Peninsula more than a century ago. The normal economical lifespan of a rubber tree is about 25 years, and, traditionally, rubberwood was used as fi rewood by the rural community. In recent decades, rubberwood has become an important timber for wood products, particularly in the furniture manufacturing sector, due to its attractive features, cream color, and good working properties. Sapstain, mold, and wooddecaying fungi are serious threats to rubberwood. Conventional chemical control has been a successful method of preventing staining fungal growth, but the effects of these chemicals are of concern because they create problems for the environment and public health. Thus, biological control has been recognized as an alternative approach to the problem. This article reviews the properties, potential utilization, and problems of protecting rubberwood against sapstain, mold, and wood-decaying fungi, and discusses the treatment methods available. Advances in biological control, particularly biofungicides, are emphasized as an alternative method for rubberwood treatment.

- by Yi Peng Teoh
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- Wood Science, Public Health, Biological Control, Case Study

Forests provide a broad economic basis for rural communities throughout the Northeastern United States. Contemporary resource management and rural development planning increasingly emphasize the integration of raw material production with forward-linked processing activities. Furthermore, the tacit acceptance of joint production of both wood and amenity-based recreation often pits the forward linked sectors of wood processing and tourism against one another

- by David Marcouiller
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- Rural Development, Regional Economics, Raw materials, Wood Products

During the last decade, the Slovak and Croatian furniture industry markets have experienced changes that have made these markets more interesting for domestic and foreign investors. Furniture manufacturers and retailers are still trying to determine the best ways to adjust to customer demands, and understanding the furniture preferences of customers would provide beneficial information to the furniture industry. The purpose of this study, which was conducted in 2016, was to improve the knowledge regarding differences in the preferences of customers for furniture materials, attributes, and styles when purchasing furniture in Slovakia and Croatia. The findings showed that Slovak and Croatian respondents differ in their preferences for furniture materials, as well as the factors that influence their purchasing decisions when buying interior and exterior furniture. Overall, it was found that wood as the furniture material, compared with the surveyed substitutes, was widely preferred among the Croatian and Slovak respondents.

- by Vladislav Kaputa
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- Consumer Behavior, Consumer Research, Wood Products, Consumer Attitudes

Summary Illegal logging and the international trade in illegally logged timber is a major problem for many timber-producing countries. It causes environmental damage, costs governments billions of dollars in lost revenue, promotes corruption, undermines the rule of law and funds armed conflict. It retards sustainable development in some of the poorest countries of the world. Consumer countries contribute to these

- by Duncan Brack
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- International Trade, Sustainable Development, East Asia, International Marketing
- by Richard Tipper
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- Engineering, Economics, Climate Change, Biomass

A common challenge related to hardwood plywood is checking along the grain of face veneers. This study tested the hypothesis that face checking of rotary peeled maple veneer plywood will be greater on the loose side of the veneer and that checking will be reduced by the application of a clear film-forming finish. Fifteen panels were constructed with the tight side of the face veneer oriented out (i.e. exposed to the atmosphere) and 15 with the loose side of the face veneer oriented out. Half of each panel was finished with lacquer and the other half left unfinished. Panels were conditioned in a hot, wet chamber, visually inspected, and then inspected again after conditioning in a hot, dry chamber. Contrary to conventional wisdom, panels oriented with the tight side of the face veneer oriented out checked significantly more than panels with the loose side oriented out. There was no effect due to finishing. Because these findings are contrary to established practices, further investigation is warranted.

- by Scott Leavengood
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- Wood Products

Plastic lumber manufactured using post consumer waste plastic has been proposed as an acceptable material for use in the construction of docks, piers and bulkheads and is touted to outlast conventional wood products due to its strength, durability and resistance to rot. This study examines the long-term engineering properties of plastic lumber manufactured using post consumer waste plastic (TRIMAX, Ronkonkoma, NY). Plastic lumber profiles were used in the decking of a pier built in West Meadow Creek, Old Field, NY during December 1995. Samples of plastic lumber were removed from the deck of the pier periodically over a two-year period and returned to the laboratory for testing. Results of engineering tests showed the in-plane compression modulus (260 + 30 MPa), dimensional stability and the Shore D surface hardness (60 f 2) of plastic lumber removed from the pier remained similar to or greater than their pre-placement values. In contrast, significant changes in the modulus of elasticity of plastic lumber were measured with prolonged weathering. The modulus of elasticity of plastic lumber initially decreased from 1370 Pa to 750 Pa following 12 months weathering, a decrease equal to 45% of its pre-placement value and then increased during the second year to close to its initial value. The high variability in the modulus of elasticity should restrict the use of plastic lumber profiles to non-load bearing structural applications. O

- by Christopher Berndt
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- Engineering, Environmental Sciences, Wood Products, Second Year

The cell wall of wood tracheids is made up of various layers, distinguished from one other by the alignment of the innumerable, fine crystalline cellulose microfibrils within each layer that helically wind about the cell lumen. Microfibrils themselves are embedded in a die den Durchschnitts-Mikrovibrillenwinkel in einem gegebenen Holzstück reflektiert. Aufgrund dessen wurden akustische Methoden entwickelt, um die Geschwindigkeit der Schallausbreitung zu messen, die direkt mit der Festigkeit des Holzes korreliert und damit auch abhängig ist von der Ultrastruktur der Zellwand. In der Grundgleichung, E dynamic =qV 2 , wird der akustische Modulus von zwei Komponenten abgeleitet, der Dichte, q, und der Schallgeschwindigkeit, V. Letztere bezieht sich auf die intrinsische Holzqualität und die Ultrastruktur der Tracheiden-Wand. Es wird gezeigt, dass die akustische Methode in der Lage ist, Bäume und Rundholz gemäß ihrer Eignung für Bauholz und für eine Bandbreite von Fasereigenschaften, im Interesse der Papierhersteller, zu sortieren und einzuteilen. Auf diese Weise finden akustische Methoden Anwendung bei der Aufzucht von Bäumen, ihrer Abholzung und Verarbeitung.

- by Håkan Lindström
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- Genetics, Building, Wood Products, Wood Quality