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Wood-polymer hybrids demonstrate unique perspectives in green architecture, energy-efficiency building, optoelectronics, photovoltaic devices, and energy storage materials. The fabrication of wood-polymer hybrids preliminary involves the acquisition of delignified wood templates. In this framework, the potentiality of species diffused in the Mediterranean area is nearly unexplored. For such purpose, four hardwoods (Beech, European Hop Hornbeam, Turkey Oak and Paulownia) and one softwood (Corsican Pine) have been selected on the basis of their anatomical features, density, and potential exploitation of natural resources. The goal is to evaluate and compare the properties of delignified woods derived from the selected species for the fabrication of wood-polymer hybrids, including transparent wood products. Wood samples of different cut (longitudinal or transversal) and thickness (1 mm or 3 mm) were soaked in an alkaline sulfite solution and mildly bleached in hydrogen peroxide. Dry mass loss was determined in different experimental conditions. Macro- and microstructure of delignified woods have been investigated by optical microscopy, scanning electron microscopy, infrared spectroscopy and X-ray diffraction analysis. Thermal degradation profiles were acquired by thermogravimetry, the total transmittance measured in the UV–Vis range and mechanical properties evaluated by tensile tests. The dry mass loss ranged within 26–52%. Delignified hardwoods showed enhanced optical transmittance especially Paulownia (+ 80%) and Turkey Oak (+ 140%), characterized by large vessels and thin cell walls, while the macro- and mesostructure along with tensile properties were preserved. These cellulose-rich wood templates deserve to be further considered for the fabrication of wood-polymer hybrids and particularly transparent wood products. [ABSTRACT FROM AUTHOR]

Discerning whether certain timber species were harvested from natural forests versus often less restricted planted forests can help ascertain the legality of wood products that enter the global market. However, readily available global planted forest data to the species level have been scarce. We confronted the need for such data by developing a two-pronged dataset, consisting of 'polygon' and 'non-polygon' location-based data, collectively, Planted Forest Timber Data. We obtained the polygon data from the World Resources Institute's Spatial Database of Planted Trees v2.0, extracting data specific to traded timber species. We derived the non-polygon data from peer-reviewed literature and government documents. The polygon dataset encompasses 27 countries and 253 species and the non-polygon dataset spans 91 countries and 447 species. We envision that the more these two living datasets grow, the more they will mutually benefit from one another for data cross-validation. This assembled information is meant to equip global leaders in forest governance, policy, enforcement, and research with vetted data for promoting legal timber trade and protecting biodiversity. [ABSTRACT FROM AUTHOR]

Demand for tropical timber is expected to rise due to an increased global need for sustainable renewable materials. However, sustainable tropical timber production remains a challenge for the global wood product supply chain, especially for high-value tropical hardwoods. Restoration of degraded lands through enrichment planting of native hardwood species could provide a solution, but the financial viability of using native tropical tree species remains largely unknown. We evaluated the financial viability of 22 hardwood tree species native to northern Borneo in enrichment plantings of a degraded forest in Sabah, Malaysia. We investigated how the species' financial value, expressed as an internal rate of return (IRR) based on land expectation value, varied with their functional trait composition. We found that high financial value was positively correlated with trait values associated with a conservative growth strategy, i.e., financial value was negatively correlated with leaf calcium, magnesium, and nitrogen content, as well as with leaf pH and specific leaf area. Trees with these traits showed a high IRR, partly explained by relatively fast growth and high survival rates. For the most economically promising species, Shorea macrophylla, we estimated that enrichment planting for forest restoration could reach IRRs up to 7.8%. Our results showed that enrichment planting for high-value hardwood production in degraded forests can be financially viable, with variation among species, and that various traits associated with a more conservative growth strategy were linked to high financial value. [ABSTRACT FROM AUTHOR]

The current demand for wood products is growing globally. Hybrid poplars are fast growing trees and it is beneficial to expand their cultivation area. Digital mapping techniques based on land suitability assessment can effectively support land use decision-making processes in this perspective. The aim of this study was to develop a model to produce land suitability maps to determine the potential production area of hybrid poplar (Populus × canadensis Moench) in Italy. The evaluation was based on a fuzzy logic procedure to generate a raster map with a pixel resolution of 250 m over the country. The modelling approach is planning-oriented: the objective is to predict, on a national scale, the suitability of the land for poplar cultivation by taking into account environmental factors for which geodatabases with adequate and comparable spatial resolution are available on a national scale in Italy. Georeferenced databases of experimental poplar plantations were used as calibration dataset. The assessment identified around 145,000 hectares of highly suitable land and around 1,926,500 hectares of suitable land for hybrid poplar cultivation in Italy. These areas are mainly located in northern Italy (around 36% of the territory) and, to a lesser extent, in central Italy (around 19%) and in southern Italy and the islands (less than 3%). The modelling approach adopted can be easily replicated in other geographical areas or at finer scales, provided that appropriate data are available. [ABSTRACT FROM AUTHOR]

Wood degradation by termites is a major concern for researchers, builders of timber-frame houses and stored wood products. This study aimed to determine the wood-degrading Isopterofauna in the cities of Yaoundé and Douala, Cameroon. Woods deposits and joineries workshops in the two cities were investigated monthly over 12 months, and termites were collected from wood species identified by their vernacular names. A total of 44 samples of wood-attacking termites were collected, grouped into two families (Rhinotermitidae, Termitidae), six subfamilies (Rhinotermitinae, Apicotermitinae, Coptotermitinae, Macrotermitinae, Nasutermitinae and Termitinae) and nine species. The species Nasutitermes arborum (14 samples) and Schedorhinotermes putorius (12 samples) were the most common in the city of Yaoundé. Only three species were found in Douala, mainly Coptotermes sp. (three samples). Of the 21 wood species examined in the two cities, Entandrophragma cylindricum hosted the highest termite species richness (six species). These findings are a milestone in the study of termites on lumber in storage and could be used by researchers and agents in the timber industry to make decisions regarding the application of pesticides on wood. [ABSTRACT FROM AUTHOR]

At the end of the last century, European Union (EU) energy policies encouraged the use of dedicated short rotation forestry (SRF) plantations in member countries in which fast-growing woody species are grown for energy purposes. Recently, in Italy some SRF plantations developed in the 90s have been abandoned or managed more extensively for economic and environmental reasons. However, these abandoned plantations can play a key role in biodiversity conservation and carbon storage. The present study is aimed to estimate carbon stock (C-stock) in living biomass and deadwood in three abandoned SRF plantations in Central Italy. The C-stock was estimated in three different 20-years SRF plantations (hybrid poplar, willow, black locust) located on the same site and unmanaged for 15 years. The results show a C-stock considering three of five C pools equal to: 47.30 MgC ha−1 for hybrid poplar (65.3% in biomass and 34.7% in deadwood respectively), 23.02 MgC ha−1 for willow (77.6% and 22.4% respectively), and 80.41 MgC ha−1 for black locust (95.9% and 4.1% respectively). Outcomes of this research offer support for the forest restoration practices of similar abandoned SRF plantations. The application of extensive management techniques and the development of the naturalization process will ensure the role of biodiversity reservoir of these plantations, helping their evolution toward semi-natural systems mainly oriented to biodiversity conservation and climate change mitigation. [ABSTRACT FROM AUTHOR]

This paper presence an analysis of the effect of the moisture content of woody biomass on the mechanisms of its ignition and combustion. Experiments were performed using an experimental setup under heating conditions similar to those in the combustion chamber of typical boiler units (873–1273 K). It was found that ignition occurred in the gas phase at a distance depending on the ambient temperature. The higher the air temperature, the larger the distance from the particle surface to the combustion zone of gaseous products of wood pyrolysis. Based on the results of the experiments, the effect of the type of woody biomass on the characteristics and conditions of fuel ignition was established. The effect of spatial orientation of the wood fiber relative to the heat flux direction on the ignition characteristics and conditions was analyzed. [ABSTRACT FROM AUTHOR]

The histogenesis of reaction wood in woody plants is a promising area of exploration for emerging wood technology products and for a generalized understanding of stress physiology. The activity of total protein and antioxidant enzymes were measured during the development of normal and reaction wood (opposite wood and tension wood) in the bole of poplar trees (Populous alba L.) induced by two levels of sustained bending stress to produce moderate and severe reaction wood. Four-year-old poplars were induced to produce reaction wood by sustained bending to 0, 35 and 80° from the vertical position. The activity of antioxidant enzymes was studied with repeated sampling during one growing season. Severe reaction wood showed higher levels of H2O2 and enzymes than moderate reaction wood. Tension wood showed a higher accumulation of total protein than opposite wood at the beginning and end of the bending treatment and opposite wood showed higher enzymatic activity. H2O2 and antioxidant enzymes were also sensitive to mechanical bending stress; compared to normal wood, tension wood and opposite wood which showed higher enzymatic activity coupled with higher amounts of total H2O2. Ascorbate peroxidase was more active than glutathione peroxidase in both tension and opposite wood at some periods of sampling. [ABSTRACT FROM AUTHOR]

The differential swelling seen between softwood opposite wood (OW) and its neighbouring compression wood (CW) developed in branches prompts several engineering issues such as dimensional instability and cracking. For a more efficient use of resources, the inevitable CW and OW should not be discarded or used as fuel, but incorporated into engineered wood products. Swelling is a hygroelastic phenomenon, where both the swelling and elastic properties of CW and OW are needed in order to make proper structural predictions. In this paper, swelling coefficients and moisture dependent elastic moduli for both CW and OW in the three principal material directions are provided along with measurements of moisture content, density, and microfibril angle. The small deformations necessitate the use of precise X-ray micro-computed tomography for measurements. The results indicate that CW and OW from Norway spruce branches differ in swelling, especially in longitudinal direction at low moisture content. It is noted that CW is a wood type with less pronounced anisotropic behaviour than both OW and normal wood from the stem, with the elastic moduli less sensitive to moisture changes in both longitudinal and transverse directions. [ABSTRACT FROM AUTHOR]

Efficient forest operations are essential for forest enterprises, who provide wood and numerous ecosystem services for the society. Important factors influencing the efficiency of forest operations, and thus the harvesting costs, are the level of mechanization, the harvesting method applied, the forest road network, and the training of the labourers. The cost of labour, i.e. salaries, is another important driver of harvesting costs. However, its effect on and relative importance for overall harvesting costs is poorly described in the scientific literature. Thus, this study aims to analyse the influence of labour costs in more detail, especially on the country-wide wood harvesting potentials. In addition, we aimed to cross-compare the effect of labour costs with the effect of switching to a more efficient harvesting method. For this purpose, we calculated timber harvesting costs with varying salaries for all sample plots of the Swiss National Forest Inventory (NFI) for both, the currently applied harvesting method recorded in the NFI, and the potential best suitable harvesting method. A 1% change in labour costs affects harvesting costs by 0.33–0.77%, depending on the harvesting method applied. The influence is larger for systems that involve a large share of motor-manual work and for cable-based methods. Changing labour costs by ± 30% affects the number of plots for which timber harvesting is economically feasible, by 5 to 15 percent points. The effect of switching from the current to the best suitable harvesting method is comparable to that of reducing labour costs by 15–30%. These results indicate that the efficiency of wood harvesting can be increased with further mechanization and does not require cutting salaries of forestry personnel. In that, our results may inform forestry planning and policy making at regional to national level. [ABSTRACT FROM AUTHOR]

Engineered wood products, such as oriented strand board (OSB), are widely used as the primary structural component in both residential and commercial lumber construction, primarily due to their renewability, aesthetic appeal, and excellent mechanical properties. Unfortunately, the inherent flammability of these wood-based composites poses an ongoing risk to society and the environment. In an effort to reduce its flammability, a polyelectrolyte complex (PEC) coating consisting of sodium polyborate (SPB) and polyethylenimine (PEI) was deposited on OSB using a simple two-dip process. This PEC treatment imparts self-extinguishing behavior to OSB and reduces the total heat release by 21% and total smoke release by 79%, while increasing the time to ignition by 18% relative to untreated OSB. Furthermore, the PEI/SPB coating adds little additional weight (5.8 wt%) to the oriented strand board, preserving visual aesthetics and maintaining mechanical properties. The main flame-retardant effect occurs by condensed phase action via a combination of intumescence and thermal barrier mechanisms. Improving the fire protection of OSB and other engineered wood materials through a simple and environmentally benign treatment will increase their potential as a largely renewable building material, promoting a sustainable bioeconomy. [ABSTRACT FROM AUTHOR]

Chitosan and bio-based epoxy resins have emerged as promising formaldehyde-free replacements for traditional urea–formaldehyde (UF) adhesives in engineered wood products. This study evaluated five chitosan-to-epoxy weight ratios (3:1, 2:1, 1:1, 1:2, 1:3) as adhesives for hot-pressing medium density fiberboards (MDF) using mixed hardwood fibers. Increasing the epoxy ratio reduced viscosity and gel time, facilitating spraying and fast curing. The density of the formulated MDFs increased with higher epoxy ratios, ranging from 679 kg/m3 for the 3:1 ratio to 701 kg/m3 for the 1:3 formulation, meeting the 500–900 kg/m3 density range specified in EN 323. The 1:3 epoxy-rich formulation enhanced modulus of rupture (MOR) to 31 MPa and modulus of elasticity (MOE) to 2392 MPa, exceeding the minimum requirements of 16 MPa and 1500 MPa set out in EN 310 and EN 316, respectively. Dimensional stability peaked at 5% thickness swelling for the 1:3 formulation after 24 h water soaking, fulfilling the < 25% requirement per EN 316. Internal bond strength reached a maximum of 0.98 MPa for the 3:1 chitosan-rich formulation, satisfying the 0.40 MPa minimum per EN 319. One-way ANOVA tests showed the adhesive ratio had a significant effect on mechanical properties and dimensional stability at 95–99% confidence levels. Duncan's multiple range test revealed the 1:3 ratio boards exhibited statistically significant improvements compared to untreated group. Overall, tailoring the ratios achieved well-balanced properties for MOR, MOE, and dimensional stability, demonstrating potential to replace UF resins. [ABSTRACT FROM AUTHOR]

Thermal induced pyrolysis and the following flaming ignition of solid combustible play crucial roles in determining the occurrence of fire and the subsequent flame spread. This contribution reviews recent advances in global investigation on these two topics. Solid fuels involved in this study covering from natural materials, such as wood and biomass-based products, to artificially synthetized substances, encompassing neat polymers and functional composites, are in dense continuous form rather than piled combustibles. Most frequently utilized experimental methodologies, from microscale (TGA, DSC, STA) to bench-scale (cone calorimeter, FPA, etc.), and the corresponding analytical or numerical methods employed to extract kinetics and thermodynamics from experimental data are introduced. Meanwhile, the controlling mechanisms of piloted and auto ignitions, various types of ignition criteria, influential factors of ignition, and the modelling techniques are elaborated. Smoldering combustion, glowing ignition, and utilization of flame retardant to suppress pyrolysis or delay ignition time are mentioned in some sections, but not discussed in detail as they are beyond the focused scope. Finally, the challenging issues encountered in current stage which deserve further endeavors are indicated. [ABSTRACT FROM AUTHOR]

Background: Forests mitigate climate change by reducing atmospheric CO 2 -concentrations through the carbon sink in the forest and in wood products, and substitution effects when wood products replace carbon-intensive materials and fuels. Quantifying the carbon mitigation potential of forests is highly challenging due to the influence of multiple important factors such as forest age and type, climate change and associated natural disturbances, harvest intensities, wood usage patterns, salvage logging practices, and the carbon-intensity of substituted products. Here, we developed a framework to quantify the impact of these factors through factorial simulation experiments with an ecosystem model at the example of central European (Bavarian) forests. Results: Our simulations showed higher mitigation potentials of young forests compared to mature forests, and similar ones in broad-leaved and needle-leaved forests. Long-lived wood products significantly contributed to mitigation, particularly in needle-leaved forests due to their wood product portfolio, and increased material usage of wood showed considerable climate benefits. Consequently, the ongoing conversion of needle-leaved to more broad-leaved forests should be accompanied by the promotion of long-lived products from broad-leaved species to maintain the product sink. Climate change (especially increasing disturbances) and decarbonization were among the most critical factors influencing mitigation potentials and introduced substantial uncertainty. Nevertheless, until 2050 this uncertainty was narrow enough to derive robust findings. For instance, reducing harvest intensities enhanced the carbon sink in our simulations, but diminished substitution effects, leading to a decreased total mitigation potential until 2050. However, when considering longer time horizons (i.e. until 2100), substitution effects became low enough in our simulations due to expected decarbonization such that decreasing harvests often seemed the more favorable solution. Conclusion: Our results underscore the need to tailor mitigation strategies to the specific conditions of different forest sites. Furthermore, considering substitution effects, and thoroughly assessing the amount of avoided emissions by using wood products, is critical to determine mitigation potentials. While short-term recommendations are possible, we suggest risk diversification and methodologies like robust optimization to address increasing uncertainties from climate change and decarbonization paces past 2050. Finally, curbing emissions reduces the threat of climate change on forests, safeguarding their carbon sink and ecosystem services. [ABSTRACT FROM AUTHOR]

Superwood is a densified wood product that shows promise as a lightweight and renewable alternative for metallic materials. In order for this high-performance new material to be used in multi-material products, it must be able to be joined with other major materials. For example, joining superwood to aluminum would provide a key enabling technology for its use in automotive components since aluminum is presently a major lightweight material for such applications. In this paper, a methacrylate-based adhesive has been identified to provide high lap shear strength (7.5 MPa) for aluminum-to-superwood joints. The aluminum-to-superwood samples were prepared with different amounts of pre-polishing to create openings to the pores in the superwood so adhesive could penetrate into them and create a mechanical interlock, in addition to the hydrogen/chemical bonding at the surface between the methyl methacrylate (MMA) in methacrylate-based adhesive and the cellulose in superwood. For aluminum samples, a thin layer (typically a few nanometers) of oxide film on the surfaces provides hydrogen/chemical bond to MMA structure in the adhesive layer. The failure strength of the superwood-to-aluminum joint sample is about 50% higher than that of natural wood to natural wood joint sample and comparable to that of aluminum-to-aluminum joint sample. [ABSTRACT FROM AUTHOR]

Background: Wood products continue to store carbon sequestered in forests after harvest and therefore play an important role in the total carbon storage associated with the forest sector. Trade-offs between carbon sequestration/storage in wood product pools and managed forest systems exist, and in order for forest sector carbon modeling to be meaningful, it must link wood product carbon with the specific forest system from which the products originate and have the ability to incorporate in situ and ex situ carbon synchronously over time. Results: This study uses elements of a life cycle assessment approach, tracing carbon from US southern pine timber harvests to emission, to create a decision support tool that practitioners can use to inform policy design around land- and bioproduct-based mitigation strategies. We estimate that wood products from annual loblolly and shortleaf pine timber harvests across the southern US store 29.7 MtC in the year they enter the market, and 11.4 MtC remain stored after 120 years. We estimate fossil fuel emissions from the procurement, transportation, and manufacturing of these wood products to be 43.3 MtCO2e year−1. We found that composite logs, used to manufacture oriented strand board (OSB), were the most efficient log type for storing carbon, storing around 1.8 times as much carbon as saw logs per tonne of log over 120 years. Conclusions: Results from our analysis suggest that adjusting rotation length based on individual site productivity, reducing methane emissions from landfills, and extending the storage of carbon in key products, such as corrugated boxes, through longer lifespans, higher recycling rates, and less landfill decomposition could result in significant carbon gains. Our results also highlight the benefits of high site productivity to store more carbon in both in situ and ex situ pools and suggest that shorter rotations could be used to optimize carbon storage on sites when productivity is high. [ABSTRACT FROM AUTHOR]

The present research aims at analyzing the determinants of trade in forest products across BRICS and EU nations by using forest cover as one of the determining factors. For this purpose, a gravity model has been utilized for the country panel of BRICS and EU from 1996 to 2020. Five product categories corresponding to the forest trade (at HS-2 level) have been considered for the analysis. Further, Poisson pseudo maximum likelihood method has been used to estimate the gravity model. The study found that the forest cover of the trading nations from BRICS and EU has affected bilateral exports of primary wood products, wood pulp products, and related items significantly. The control variables included in the gravity model have resonated the results of existing literature. The study provides good policy insights on promoting trade in forest products by adopting appropriate forest conservation policies and other interventions that can help countries in increasing their respective forest covers. [ABSTRACT FROM AUTHOR]

Tribes Coriacephilini, Corthylini, Cryphalini, Ernoporini, Trypophloeini, Xyloctonini, and Xyloterini (Coleoptera: Curculionidae; Scolytinae) include spermophagous, phloeophagous, and xylomycetophagous species. Besides direct damage caused by burrowing into host plant tissues, some species are vectors of aggressive pathogens causing plant dieback and death, with consequent economic and ecological relevance. The international trade in plants and wood products is one of the main pathways for the introduction of non-native species worldwide. In this context, data availability on host plants and their economic uses is essential in pest risk assessment and for planning effective detection and monitoring strategies against invasive species. This paper provides a complete and updated list of host plants, with economic categorization, for 2139 scolytine species. [ABSTRACT FROM AUTHOR]

For the utilization of silver birch (Betula pendula Roth) in load-bearing engineered wood products (EWPs), reliable bonding in production is a prerequisite. The current knowledge regarding the bonding of birch in EWP applications is limited. Extractives are considered a general factor of attention when securing bonding quality. Thus, in this study, the effects of hydrophilic extractives on several adhesion-related bulk and surface properties of silver birch wood were studied, e.g., vapor sorption, swelling behavior, microstructure, wettability, and mechanical properties. The extraction procedure slightly affected vapor sorption causing a reduction in swelling pressure. The extraction also led to a lower Young's modulus, as seen by compression tests. Control experiments with vapor-treated specimens, however, indicated that the effects were originating from the water imbibition and not due to the removal of extractives per se. This was supported by X-ray diffraction results, which were similarly affected by both vapor and extraction treatment. Therefore, the results indicate that the hygric history of the specimens was affecting the wood due to plasticization, increasing mobility, and thereby likely allowing biopolymer reconfiguration and subsequent quenching during re-drying, even though surface-free energy and wettability were not considerably affected. The extent to which these changes appear permanently or temporarily remains an open research question. [ABSTRACT FROM AUTHOR]

Environmentally friendly biopolymer-based wood adhesives are an inevitable trend of wood product development to replace the use of harmful formaldehyde-based adhesives. In this research, a new eco-friendly modified cassava starch waste-based adhesive via carboxymethylation (CMS), and blending with polyvinyl alcohol (PVA), tannic acid (TA) and green synthesized silver nanoparticles (AgNPs) was prepared. The effects of TA content on green synthesis of AgNPs (Ag-TA) and bio-adhesive nanocomposite properties were investigated. The use of 5 wt% TA for AgNPs synthesis (Ag-TA-5) resulted in a uniform particle size distribution. The plywood prepared with Ag-TA-5 provided the highest dry and wet shear strength at 1.95 ± 0.11 MPa and 1.38 ± 0.3 MPa, respectively. The water absorption and thickness swelling of this plywood remarkably decreased up to 10.99% and 6.79%, respectively. More importantly, the presence of Ag-TA in CMS/PVA adhesive successfully inhibited the invasion of mold and bacteria. Based on the cyclic delamination test, the adhesive bond durability of bio-adhesive containing Ag-TA-5 could meet the requirement of the AITC Test T110-2007 and was comparable to commercial adhesives. The added advantage of the prepared bio-adhesive was its synthesis from agro-waste products and possible economically viable production at industrial level. [ABSTRACT FROM AUTHOR]

Harvested wood/bamboo products (HWP/HBP) constitute a large global carbon stock. However, the contribution of HBP to carbon stocks has been neglected in mixed wood and bamboo data, especially in China. Therefore, the production approach and the first-order decay method were used to estimate the spatiotemporal carbon stock change in HWP/HBP based on provincial production data from the China Forestry Statistical Yearbooks for 1987–2020. The results showed that China's total carbon stocks of HWP and HBP were 328.7 teragram carbon (TgC) and 129.7 TgC between 1987 and 2020. Of this, the HWP carbon stock was mainly sourced from three provinces across the north and south: Guangxi (60.8 TgC), Heilongjiang (37.2 TgC), and Fujian (24.2 TgC), and HBP carbon stock was mainly sourced from three southern provinces: Fujian (33.4 TgC), Guangxi (20.3 TgC), and Zhejiang (13.7 TgC). The proportion of the HBP carbon stock in the total carbon stock increased from 20% in 2010 to 28% in 2020, indicating that bamboo products play an important role in the accumulation of carbon stocks in China. The differences in contributions to spatiotemporal trends between the provinces provide more specific information to make precise decisions about forest management and carbon sequestration. [ABSTRACT FROM AUTHOR]

Design models are commonly used in fire safety design of light timber frame assemblies. Parameters for use in the models are available for rectangular members with mineral wool, wood fibre or cellulose insulation and for assemblies with I-joists and mineral wool. For assemblies where I-joists and combustible insulations are combined, design parameters are missing. Five fire experiments with two I-joist types and four combustible insulation products have been conducted. The aim was to study charring of I-joist flanges and recession rates of combustible insulations and in addition, to compare their behaviour to the new and existing models of Eurocode 5. Charring rates for the flanges were 0.40–0.76 mm/min and 0.54–1.72 mm/min for the protected and post-protected phase, respectively. Rates decreased with increasing flange size. Charring rates for flanges of solid wood and LVL were comparable. The results show that lateral charring of I-joist flanges can be significant in the protected phase. The tested insulation products showed a lower recession rate than values reported for glass wool insulation, with a more pronounced difference for wood fibre and cellulose insulations. The low recession rates compared to previously reported generic values can possibly be explained by better product-specific properties, negligible shrinking and slightly different test set-up. The insulation stayed well in place after gypsum board fall-off and best-practice for keeping the insulation in place is given. The results, completed with future loaded full-scale tests, can give basis for further development of design models for assemblies with I-joists and combustible insulations. [ABSTRACT FROM AUTHOR]

Predominantly linear use of wood curtails the potential climate-change mitigation contribution of forestry value-chains. Using lifecycle assessment, we show that more cascading and especially circular uses of wood can provide immediate and sustained mitigation by reducing demand for virgin wood, which increases forest carbon sequestration and storage, and benefits from substitution for fossil-fuel derived products, reducing net greenhouse gas emissions. By United Kingdom example, the circular approach of recycling medium-density fibreboard delivers 75% more cumulative climate-change mitigation by 2050, compared with business-as-usual. Early mitigation achieved by circular and cascading wood use complements lagged mitigation achieved by afforestation; and in combination these measures could cumulatively mitigate 258.8 million tonnes CO2e by 2050. Despite the clear benefits of implementing circular economy principles, we identify many functional barriers impeding the structural reorganisation needed for such complex system change, and propose enablers to transform the forestry value-chain into an effective societal change system and lead to coherent action. Cascading and especially circular wood uses enhance climate-change mitigation achieved by forestry. In combination, these measures could cumulatively mitigate 258.8 million tonnes CO2e by 2050 in the UK but implementation barriers must be overcome. [ABSTRACT FROM AUTHOR]

Small-scale private forests cover large areas in Europe and often contain structures and habitats of high nature conservation value that are increasingly put under pressure due to a rising interest in fuelwood and wood products. We investigate the distribution of variables like living tree and deadwood volumes, management intensity, diversity and density of tree-related microhabitats recorded in 81 small-scale private forest parcels in the Lower Saxon Hills (northwest Germany). We provide an assessment of the influence of predictors like the individual forest owners' goals and activities, as stated by them in a quantitative survey, as well as landscape parameters like parcel size, slope, landscape fragmentation and forest continuity. Our results indicate that there are two types of structures of conservation value in small-scale private forests: slowly evolving structures (type A) like large-diameter living trees and tree-related microhabitats which mostly depend on landscape parameters that act on longer time scales, and fast evolving structures (type B) like deadwood that are influenced by both owner attitudes and landscape parameters. The resulting implications for integrative forest and conservation management are discussed. When considering the conservation of the slowly evolving type A structures, long-term commitments to conservation legislation, financial incentives and generation-spanning education of forest owners are necessary. Efforts to promote the faster evolving type B structures might prove particularly advantageous in small-scale private forests given the structural diversity of the stands, but also the often strong identification of owners with their land. [ABSTRACT FROM AUTHOR]

The present work was conducted in the forest-based ecosystem of Chhattisgarh in order to assess the varietal performance of coffee varieties along with silver oak in terms of growth, biomass, and carbon dynamics. Five coffee varieties were planted in silver oak shade in a randomized block design with four replications. The aim of the present investigation is to assess the economic and ecological feasibility of forest-based coffee plantations in the Bastar region of Chhattisgarh. Findings reflect the maximum under-storied plant height in Chandragiri Dwarf (1.85 m) which was at par with CxR (1.82 m) and San Ramon (1.71 m). The maximum above and below-ground carbon stock (48.40 and 12.09 Mg ha−1, respectively), as well as carbon dioxide (CO2) mitigation (177.63 and 44.41 Mg ha−1, respectively) from the under-storied coffee plantation, was recorded in CxR. In the upper-storied plantation, the above and below-ground biomass of silver oak recorded the maximum carbon stock (201.24 and 50.31 Mg ha−1, respectively) and CO2 mitigation (738.54 and 184.63 Mg ha−1) in S-8 intercropped lines. The highest value of carbon credit was recorded under the coffee variety S-8 and silver oak agroecosystem. The S-8, CxR, and Chandragiri Dwarf varieties performed quite well in terms of the expected value of carbon credit. [ABSTRACT FROM AUTHOR]

Social reforestation programs plant trees on degraded, uncultivated land in low-income regions to allow the local population to generate income from selling wood products and—in case of agroforestry systems—to grow food. For fundraising it is of interest to demonstrate not only positive social impacts but also environmental ones. Proving negative greenhouse gas (GHG) emissions would allow the programs to enter the market for carbon offsetting projects and liberate further funding. In a case study, a social reforestation program in Kalimantan, Indonesia, is analyzed. GHG emissions (according to ISO 14067, PAS 2050 and EU ILCD Handbook for LCA) of the main product, laminated veneer lumber plywood, are determined as 622 and 21 kg CO2-e/m3 for short-term and long-term (above 100 years) plywood use, respectively. Switching to lignin-based resins and renewable electricity could reduce emissions down to − 363 kg CO2-e/m3 for long-term use. The analyzed agroforestry system produces almost carbon–neutral plywood today and could be climate positive in the mid-term. [ABSTRACT FROM AUTHOR]

National Fire Protection Association standard 1403 provides the fire service with guidance for conducting effective live fire training with the goal of minimizing health and safety hazards. The document provides guidelines for materials to be included in the training fuel package, but the fire service has raised questions about the use of specific types of wood products for this purpose. In this study, the fire dynamics generated when utilizing five different Class A materials that have been historically employed as training fuels [low density wood fiberboard, oriented strand board (OSB), pallets, particle board, plywood] in a single compartment fire training structure (Fire Behavior Lab) were characterized. A specific focus was placed on understanding the thermal and visual environment created for firefighters located at typical locations for instructors (front and rear of structure) and students (middle of the structure). The pallet fuel package required the longest time to transition through the six ventilation cycles while the OSB fuel package was the quickest. Additionally, the most consistent fire dynamics were demonstrated with the OSB fuel followed by particle board and plywood, while fiberboard and pallets resulted in less repeatable flashover or rollover demonstration. The OSB fuel package resulted in the highest peak heat fluxes and pallets resulted in the lowest. The most severe exposures were measured at the front instructor location. To control thermal risks when conducting training in the Fire Behavior Lab structure, instructors and students should orient themselves as low as possible in the observation area and behind the interior baffle when possible. Considering the high radiant exposures for the front instructor location, providing a local shield and reducing the time in the training structure can also reduce risk for thermal injury or personal protective equipment damage. Overall, different fuels can impact thermal exposures to firefighters, but varying fuels also affects the consistency of the fire dynamics being presented to the firefighting students. [ABSTRACT FROM AUTHOR]

The carbon stock function of harvested wood products (HWPs) is attracting attention among climate change countermeasures. Among HWPs, particle board (PB) and fiberboard (FB) mainly use recycled materials. This study estimated carbon stocks of PB and FB and their annual changes over the past 70 years in Japan using three methods of the Intergovernmental Panel on Climate Change guidelines: Tiers 1–3. Tier 1 uses first order decay (FOD), a 25-year half-life, and the Food and Agriculture Organization of the United Nations database. Tier 2 uses FOD, a 25-year half-life, and Japan-specific statistics. Tier 3 uses a log-normal distribution for the decay function and a 38–63-year half-life of building PB/FB. Japan's PB and FB carbon stocks have increased for the past 70 years. The latest carbon stock in early 2022 and the annual change in carbon stock in 2021 was 21.83 million t-C and 0.42 million t-C/year, respectively for Tier 3. Tier 3 has the highest estimation accuracy by using decay functions and half-lives that match the actual conditions of building PB and FB, whereas Tiers 1 and 2 were underestimates. Approximately 40% of the carbon stock is derived from waste wood, which extends its utilization. [ABSTRACT FROM AUTHOR]

Wood processing is one of the most widely used in agriculture and industry. Low precision and high time delay of machine learning in wood defect detection are currently the main factors restricting the production efficiency and product quality of the wood processing industry. An SPP-improved deep learning method was proposed to detect wood defects based on the basic framework of the YOLO V3 network to improve accuracy and real-time performance. The extended dataset was firstly established by image data enhancement and preprocessing based on the limited samples of the wood defect dataset. Anchor box scale re-clustering of the wood defect dataset was carried out according to the defect features. The spatial pyramid pooling (SPP) network was applied to improve the feature pyramid (FP) network in YOLO V3. The validity and real-time performance of the proposed algorithm were verified by a randomly selected test set. The results show that the overall detection accuracy rate on the wood defect test dataset reaches 93.23% while the detection time for each image is within 13 ms. [ABSTRACT FROM AUTHOR]

Heat treatment is an effective sanitization method used for over half a century to reduce the risk of transporting pests associated with wood products. The determination of precise lethal heat treatment parameters for pests is critical for the development of globally harmonized plant protection regulatory treatment policies. Separation of heat treatment dose (time and temperature) from the factors associated with the method of heat application (delivery) and variables associated with wood characteristics allows for universal agreement on lethal dose and promotes efficient development of treatment schedule guidance. The Humble water bath is an effective and carefully calibrated heat treatment apparatus designed to test the effects of heat and determine lethal temperature doses. Specifications for building this apparatus and experimental treatment parameters are described. To demonstrate the capacities of the water bath apparatus, the effect of heat on a non-indigenous wood-boring beetle, Anisandrus dispar, is reported using heat-ramp schedules similar to industrial kiln heating applications. Adult A. dispar tested in vitro, did not survive 50 °C treatment temperature for 15 min time duration. [ABSTRACT FROM AUTHOR]

Rubber (Hevea brasiliensis Müll. Arg.) is a major economic crop grown in tropical areas. However, the various service functions of rubber plantations and their benefit to society, the economy and the environment are still unclear. Data on rubber planting areas, dry rubber and wood yields, carbon sequestration and oxygen release capacities, biodiversity, employment, and market prices for natural rubber and rubber wood were collected. Observations of land use patterns and functions were carried out. The results showed that the capacity of average annual carbon stock capacity of rubber plantations in China was 36.51 million tonnes. The accumulation values of carbon sequestration and oxygen release, 416.89 million tonnes and 304.42 million tonnes, respectively. A total of 849 plant species, 60 bird species, 5 species of ground beetle, 25 species of wild bees, 27 ant species, 10 termite species, 87 spider species and 38 hemipterous species were found in rubber plantations. The average annual dry rubber and rubber wood yields were 676,300 tonnes and 1.29 million m3. From 2000 to 2020, 14.20 million tonnes of dry rubber were produced and 27.02 million m3 of wood were harvested. The average annual output of dry rubber and rubber wood was US$1.86 billion, while total output value summed to US$ 39.08 billion from 2000 to 2020. Rubber cultivation and plantation operation activities employed an average of 1.11 million people annually. Land use management and natural disasters may affect the service functions of rubber plantations, which are carbon sequestration and oxygen release, maintaining biodiversity, providing dry rubber and rubber wood, maintaining water and conserving water sources, absorbing employment, changing unsustainable agricultural practices and habits of smallholders and ethnic minorities, and promoting transfer of technologies. In the future, on the basis of recognising and rationally weighing the various functions of rubber plantations and their main driving factors, smallholders are expected to maximise the social, economic and ecological functions of rubber plantations through effective crop management and utilisation of resources. [ABSTRACT FROM AUTHOR]

Recycling is emerging as both a viable alternative to extraction in many industries and a cornerstone of the circular economy. In this paper, we assess the role of paper and cardboard recycling on the forest sector, from both an economic and carbon perspective. For this purpose, we add the recycling industry to an existing forest-sector model in an attempt to capture its effects on other wood products and the overall forest resource. As the forest sector has an important potential for climate change mitigation, this model allows us to assess the effects of increased paper and cardboard recycling on the availability of the natural resource and the carbon balance of the forest sector. We show that these results are strongly linked to the hypotheses of substitutability and/or complementarity of recycled pulp and virgin pulpwood. Although we find increased emissions at the pulp sector level, the effects on emissions in other wood products are small. When pulp products are considered substitutes, we find the impact on total net sequestration to be positive. In the case where pulp products are considered complements, we find the impact on total net sequestration to be negative. [ABSTRACT FROM AUTHOR]

To upgrade the hydrophobicity, dimensional stability and mechanical properties of planted fast-growing poplar wood (Populus cathayana Rehd.), we proposed to fabricate wood-polymer composites (WDPF) by introducing biomass-derived furfuryl alcohol (FA) and polyvinyl alcohol (PVA) into wood cells after delignification. The results showed that delignification enhanced wood porosity and benefited polymer impregnation and uniform distribution in cell walls, causing higher cell wall bulking. Hydrophobic FA and PVA blocked water paths and formed films on cell surface, reducing water accommodation and hindering wood-water interaction. Consequently, the hydrophobicity and dimensional stability were highly enhanced, as indicated by the moisture content and volume change decrease by over 46% and steady high contact angle. WDPF had improved flexural strength and modulus of elasticity by over 21% and 46% respectively. Besides, the impact toughness of WDPF increased by over 90% compared to furfurylated wood. The mechanical property improvement was mainly ascribed to the combined effects of PVA-FA interaction and delignification. PVA with flexible macromolecular chains interacted with FA and wood, interrupting FA crosslinking and forming polymer networks in hierarchical structures of wood. Additionally, delignification and PVA facilitated orderly arrangement of micro-fibrils and increased crystallinity and mechanical strength. The fabrication and mechanism analysis of WDPF can be used as a reference for upgrading low-quality wood products. [ABSTRACT FROM AUTHOR]

The embodied carbon of building materials and the energy consumed during construction have a significant impact on the environmental credentials of buildings. The structural systems of a building present opportunities to reduce environmental emissions and energy. In this regard, mass timber materials have considerable potential as sustainable materials over other alternatives such as steel and concrete. The aim of this investigation was to compare the environment impact, energy consumption, and life cycle cost (LCC) of different wood-based materials in identical single-story residential buildings. The materials compared are laminated veneer lumber (LVL) and glued laminated timber (GLT). GLT has less global warming potential (GWP), ozone layer depletion (OLD), and land use (LU), respectively, by 29%, 37%, and 35% than LVL. Conversely, LVL generally has lower terrestrial acidification potential (TAP), human toxicity potential (HTP), and fossil depletion potential (FDP), respectively, by 30%, 17%, and 27%. The comparative outcomes revealed that using LVL reduces embodied energy by 41%. To identify which of these materials is the best alternative, various environmental categories, embodied energy, and cost criteria require further analysis. Therefore, the multi-criteria decision-making (MCDM) method has been applied to enable robust decision-making. The outcome showed that LVL manufacturing using softwood presents the most sustainable choice. These research findings contribute to the body of knowledge about the use of mass timber in construction. [ABSTRACT FROM AUTHOR]

Wood is undeniably the most useful and readily available natural raw material. However, the susceptibility of wood products to fire is one of the crucial challenges faced in the wood industry. The fire behaviour of wood is a very complex phenomenon due to the different constituents and their independent reactions to fire. This article presents a thorough overview of the flammability stages of wood. It covers pyrolysis, thermal oxidative decomposition, ignition, combustion and heat release as well as flame extinction mechanisms. In the area of flame retardancy, conventional wood fire retardants, nanocomposites fire retardants and wood modification processes are investigated. Factors such as wood species, moisture content, density, experimental conditions such as external heat flux, heat exposure time, wood permeability and porosity are some of the deterministic parameters characterising the fire behaviour. This paper is a one-stop-shop for researchers analysing wood flammability due to the inclusion of all aspects pertaining to the burning of wood. [ABSTRACT FROM AUTHOR]

Background: Wood biomass from forests is a renewable energy source that has the potential to support global green development. However, the process of traditional firewood extraction and its contribution to the energy supply varies and is usually underrecognized, especially in the local context. Therefore, this study aimed to describe the traditional use and estimate the supply and demand for wood bioenergy from small-scale privately owned forests (SSPF) in Ciamis Regency, West Java Province, Indonesia. Methods: The sample location was determined in 3 subdistricts, namely, Sukamantri, Ciamis, and Banjaranyar, which represent the northern, central, and southern regions, respectively. The data were collected through observations on stands, interviews with respondents, key informants from users and business actors of wood in the SSPF, and observations on the processes taking place in the flow and use of biomaterials and firewoods. Results and conclusion: Firewood is a secondary product that cannot be separated from the main products along SSPF's chain of production based on the integration of raw material sources, linkages between actors, and volume sharing. The local knowledge and wisdom entanglements included the identification of the type and quality of firewood, distribution of resource allocation for household and industrial needs, and sharing of firewood for household needs. Although wood biomass contributes to the fulfillment of households and industrial needs of 8.51 million m3, there are indications of an imbalance between the potential supply and the demand for firewood due to its high intensity of use in industries. Therefore, multistakeholder and cross-regional support are needed to achieve sustainable SSPF management and fulfill the self-sufficiency of wood energy. [ABSTRACT FROM AUTHOR]

Background: Timber harvesting and industrial wood processing laterally transfer the carbon stored in forest sectors to wood products creating a wood products carbon pool. The carbon stored in wood products is allocated to end-use wood products (e.g., paper, furniture), landfill, and charcoal. Wood products can store substantial amounts of carbon and contribute to the mitigation of greenhouse effects. Therefore, accurate accounts for the size of wood products carbon pools for different regions are essential to estimating the land-atmosphere carbon exchange by using the bottom-up approach of carbon stock change. Results: To quantify the carbon stored in wood products, we developed a state-of-the-art estimator (Wood Products Carbon Storage Estimator, WPsCS Estimator) that includes the wood products disposal, recycling, and waste wood decomposition processes. The wood products carbon pool in this estimator has three subpools: (1) end-use wood products, (2) landfill, and (3) charcoal carbon. In addition, it has a user-friendly interface, which can be used to easily parameterize and calibrate an estimation. To evaluate its performance, we applied this estimator to account for the carbon stored in wood products made from the timber harvested in Maine, USA, and the carbon storage of wood products consumed in the United States. Conclusion: The WPsCS Estimator can efficiently and easily quantify the carbon stored in harvested wood products for a given region over a specific period, which was demonstrated with two illustrative examples. In addition, WPsCS Estimator has a user-friendly interface, and all parameters can be easily modified. [ABSTRACT FROM AUTHOR]

Quality and quantity of DNA extracted from wood is important for molecular identification of wood species, which can serve for conservation of wood species and law enforcement to combat illegal wood trading. Rosewood (Dalbergia and Pterocarpus) and agarwood (Aquilaria) are the most commonly found hardwood in timber seizure incidents. To monitor international trade of timber and commercial wood products and to protect these endangered wood species from further population decline, in this study, we have compared three extraction protocols for DNA extraction from 12 samples of rosewood and agarwood timber logs, and later applied the best DNA extraction protocol on 10 commercial wood products claimed to be rosewood and agarwood. We also demonstrated the applicability of DNA mini-barcoding with multi-loci combination with reference library for identifying the species of timber and commercial wood products. We found that a silica column-based method with guanidine thiocyanate-containing binding buffer served the best in DNA extraction from different parts of wood in all three genera with good quality and quantity. Single barcode region ITS2 or multi-loci combinations including ITS2 barcode region generally provide better discriminatory power for species identification for both rosewood and agarwood. All 10 products were identified to species-level using multi-loci combination. In terms of accuracy in labelling, 80% of them were labelled correctly. Our work has shown the feasibility of extracting good quality of DNA from authentic wood samples and processed wood products and identifying them to species level based on DNA barcoding technology. [ABSTRACT FROM AUTHOR]

The main components of the birch wood were fractionated into a microcrystalline cellulose, xylose and enterosorbents by an integration of heterogeneous catalytic processes of an acidic hydrolysis and a peroxide delignification of the wood biomass for the first time. The wood hemicelluloses were hydrolyzed to xylose at a temperature of 150°C in the presence of the Amberlyst® 15 solid acidic catalyst. Then, the lignocellulosic product of the wood hydrolysis was subjected to the peroxide delignification in the formic acid–water medium in the presence of the solid TiO2 catalyst with a formation of the microcrystalline cellulose (MCC) and the organic-soluble lignin. Yields of MCC and the organic-soluble lignin proved to be 64.5 and 11.5 wt % of a mass of the prehydrolyzed wood, respectively, under the determined optimal conditions (100°C, 7.2 wt % of Н2О2, 37.8 wt % of НСООН, LWR 15, and a duration of 4 h). The enterosorbents were prepared by a treatment of the organic-soluble lignin with 0.4% NaHCO3 or hot water. The sorption capacity of these enterosorbents was 97.7 and 236.7 mg/g according to methylene blue and gelatin, respectively. These values were significantly higher than those of the Polifepan commercial enterosorbent (44 and 115 mg/g, respectively). The products of the catalytic fractionation of the birch wood were characterized by physicochemical (FTIR, XRD, SEM, and GC) and chemical methods. [ABSTRACT FROM AUTHOR]

Wood products function as carbon storage even after being harvested from forests. This has garnered attention in relevance to climate change countermeasures. In the progress of efforts toward climate change mitigation by private companies, the effective use of wood products has been an important measure. However, the methodology for accounting carbon stocks in wood products for private companies has not been established. Therefore, this study investigated methods for estimating carbon stocks in wood products used in wooden houses built by private enterprises, targeting a major company in the Japanese building industry. The results indicated that both the direct inventory method and flux data method (FDM) were applicable for estimating the carbon stocks. These two methods use data that can be obtained from many other building companies, thus, indicating high versatility. The log-normal, Weibull, normal, and logistic distributions, in descending order, proved to be suitable lifetime functions of wooden houses under the FDM, with a half-life of 66–101 years. It is important to continuously acquire time-series data on the floor areas of both newly built and existing houses and the amount of wood products used to improve the accuracy of estimates and explore future predictions. [ABSTRACT FROM AUTHOR]

This study focuses on the development, implementation and application of a spatial-based decision support tool—named r.forcircular—aimed at quantifying both the level of the circular bioeconomy and the financial performance in the forest-based sector. The methodology merges a set of indicators based on the 4R framework (Reduce, Reuse, Recycle, Recover) of circular economy in a multicriteria approach. Outputs are computed for different scenarios and are calibrated based on variations in the selling price of raw materials and on higher mechanisation of production process phases (felling, processing, extraction and chipping of wood residues). The increase in wood assortment value leads to an improvement in the sustainability of the forest-wood supply chain in circular bioeconomy and financial terms. The application of a higher level of mechanisation seems to have conflicting results compared to those of other scenarios. The r.forcircular model was tested in an Italian case study (in the Municipality Union of Valdarno and Valdisieve in the Tuscany region, Italy) with the aim of understanding its applicability and replicability in other contexts. The results of the test showed that, in the study area, superior outcomes were observed for high forests than for coppices due to the low value of wood products obtainable from coppices. [ABSTRACT FROM AUTHOR]

Climate change mitigation trade-offs between increasing harvests to exploit substitution effects versus accumulating forest carbon sequestration complicate recommendations for climate beneficial forest management. Here, a time dynamic assessment ascertains climate change mitigation potential from different rotation forest management alternatives across three Swedish regions integrating the forest decision support system Heureka RegWise with a wood product model using life cycle assessment data. The objective is to increase understanding on the climate effects of varying the forest management. Across all regions, prolonging rotations by 20% leads on average to the largest additional net climate benefit until 2050 in both, saved emissions and temperature cooling, while decreasing harvests by 20% leads to the cumulatively largest net climate benefits past 2050. In contrast, increasing harvests or decreasing the rotation period accordingly provokes temporally alternating net emissions, or slight net emission, respectively, regardless of a changing market displacement factor. However, future forest calamities might compromise potential additional temperature cooling from forests, while substitution effects, despite probable prospective decreases, require additional thorough and time explicit assessments, to provide more robust policy consultation. [ABSTRACT FROM AUTHOR]

This study determines carbon savings related to intercropping carinata (Brassica carinata A. Braun) with loblolly pine (Pinus taeda L.) and compares it with the carbon savings associated with the production of loblolly pine only. We performed an integrated life cycle assessment to quantify the overall carbon stored under both production systems. The functional unit for analysis was a hectare of intensively managed loblolly pine plantation in the Southern United States. The system boundary started from forest management with carinata, use of wood products, the decay of wood products in landfills, and the substitution of conventional aviation fuel with carinata-based sustainable aviation fuel (SAF). Carbon stored in wood products was 5.46 t, 6.75 t, and 11.52 t C ha−1 higher than carbon stored in landfill at the end of the simulation period (100-years) for the intercropping production system for site indices 15.3 m, 18.3 m, and 21.3 m, respectively. At the end of the simulation period, the total avoided carbon savings from carinata-based SAF were 2.57 t, 4.15 t, and 4.76 t C ha−1 for site indices 21.3 m, 18.3 m, and 15.3 m, respectively. Over the simulation period, devoting the forestland for intercropping to produce SAF decreased the total carbon storage by 2.55 t, 4.08 t, and 12.49 t C ha−1 than loblolly pine only management scenario for site indices 15.3 m, 18.3 m, and 21.3 m, respectively. Our results indicate that a system-level approach should be taken for analyzing the carbon benefits related to intercropping of bioenergy crops in existing forest stands. [ABSTRACT FROM AUTHOR]

The quality control of wood products is often only checked at the end of the production process so that countermeasures can only be taken with a time delay in the event of fluctuations in product quality. This often leads to unnecessary and cost-intensive rejects. Furthermore, since quality control often requires additional procedural steps to be performed by a skilled worker, testing is time-consuming and costly. While traditional machine learning (ML) methods based on supervised learning have been used in the field with some success, the limited availability of labeled data is the major hurdle for further improving model performance. In the present study, the potential of enhancing the performance of the ML methods random forest (RF) and support vector machines (SVM) for quality classification by using semi-supervised learning (SSL) was investigated. Labeled and unlabeled data were provided by Swiss Wood Solutions AG, which produces densified wood for high-value wood products such as musical instruments. The developed approach includes labeling of the unlabeled data using SSL, training and 10k cross-validation of the ML algorithms RF and SVM, and determining the generalization ability using the hold-out test set. Based on the evaluation indices such as accuracy, F1-score, recall, false-positive-rate and confusion matrices, it was shown that SSL could enhance the prediction performance of the quality classification of ML models compared to the conventional supervised learning method. Despite having a small dataset, the work paves the way for future applications of SSL for wood quality assessment. [ABSTRACT FROM AUTHOR]

Wood is commonly used in construction, but often perceived as being less safe than structures made from non-combustible materials. With the advancement of wood products and treatment, construction techniques, and protective systems, this may not be the case any longer. Using retrospective data from fire departments across Canada, this study aimed to determine whether the type of construction material (combustible or non-combustible) affected the fire severity outcome of a one to six storey apartment building fire, after accounting for protective systems (smoke alarms and sprinklers). The study found that, after adjusting for the presence of smoke alarms and sprinklers, structures constructed from non-combustible construction materials did not perform better in terms of injuries, requiring extinguishment by fire department, or the fire spreading beyond the room of origin. The presence of working smoke alarms and sprinklers played a central role in reducing the severity outcome of a fire. Smoke alarms and sprinklers both reduced the odds of extinguishment by the fire department and the fire spreading beyond the room of origin. Sprinklers also reduced the injury rate. Overall, this study highlighted the importance of protective systems in reducing fire severity outcomes. [ABSTRACT FROM AUTHOR]

Being one of the most common wood in furniture and decoration, Fraxinus mandshurica Rupr. (F. mandshurica) is a frequently used material for wood products. However, the resulting odor problem has not yet been solved so far. Thus, this study focused on exploring odor-active compounds and investigating the effect of environmental conditions on emission and odor attributes. F. mandshurica was studied via TD–GC–MS/O combined with microchamber. Totally, 15 kinds of key odor-active compounds were detected from F. mandshurica. The main odorous components were found to be aromatics, aldehydes and ketones, esters, alcohols and acids. Six kinds of attributes played a key role in the overall odor character of F. mandshurica. Fragrant was the predominant odor impressions, followed by vinegar and antiseptic solution. The proportion of the odor-active compounds concentration to total concentration decreased with an increase in the temperature and relative humidity, while the ratio of air exchange rate to the loading factor had little effect on this. The total concentration of F. mandshurica increased as the temperature and relative humidity increased, but these decreased as the ratio of air exchange rate to the loading factor increased, while the total odor intensity reduced with the rise in the ratio of air exchange rate to the loading factor. Time was found to be the most effective factor for eliminating emissions. Considering the environmental conditions in this study, 40 °C, 60% relative humidity and a 1.0 m3·m−2 h−1 ratio of air exchange rate to loading factor are recommended to accelerate the emission of F. mandshurica. The optimum condition was found to be higher temperature, higher relative humidity and higher ratio of air exchange rate to loading factor. [ABSTRACT FROM AUTHOR]

Wood decomposition in tropical forests is strongly linked to the terrestrial carbon cycle. Our understanding of the successional changes in wood decomposition in diverse tropical forests is still limited. In this study, we tested the hypothesis that fine wood decomposition rates decline with the increasing age of successional forests due to the interspecific variation in wood density and changes in species composition. We studied fine wood decomposition in a chronosequence of tropical forests representing four successional phases in southern Mexico. Wood segments (1–7.5 cm diameter) from 30 dominant species (wood density range 0.34–0.83 g cm−3) were left on the ground for decomposition, and samples were recollected at different time intervals for three years. We used a modified negative exponential model by introducing the power parameter (p) that allowed for a time-dependent decomposition rate (k). Average k within a successional phase ranged from 0.22 to 0.39 yr−1 and declined gradually with the increase in forest age. We found a significant negative correlation between wood density and decomposition rate constants. The kspecies ranged from 0.07 to 1.11 yr−1, whereas p-parameters varied between 0.65 and 1.42. Trees such as Bursera simaruba, and Cascabela gaumeri decomposed faster, while Eugenia ibarrae, and Pouteria reticulata decomposed slower. Average fine woody debris inputs ranged from 1.2 to 3.7 Mg ha−1 yr−1 which increased with forest age. Increasing production and declining decomposition rates during succession contribute to the higher accumulation of deadwood in primary forests. The results on generalized, age- and species-specific wood decay parameters have important implications in simulating carbon dynamics of the changing tropical forests. [ABSTRACT FROM AUTHOR]

Background: The stock dynamics of harvested wood products (HWPs) are a relevant component of anthropogenic carbon cycles. Generally, HWP stock increases are treated as carbon removals from the atmosphere, while stock decreases are considered emissions. Among the different approaches suggested by the Intergovernmental Panel on Climate Change (IPCC) for accounting HWPs in national greenhouse gas inventories, the production approach has been established as the common approach under the Kyoto Protocol and Paris Agreement. However, the 24th session of the Conference of the Parties to the United Nations Framework Convention on Climate Change decided that alternative approaches can also be used. The IPCC has published guidelines for estimating HWP carbon stocks and default parameters for the various approaches in the 2006 Guidelines, 2013 Guidance, and 2019 Refinement. Although there are significant differences among the default methods in the three IPCC guidelines, no studies have systematically quantified or compared the results from the different guidelines on a global scale. This study quantifies the HWP stock dynamics and corresponding carbon removals/emissions under each approach based on the default methods presented in each guideline for 235 individual countries/regions. Results: We identified relatively good consistency in carbon stocks/removals between the stock-change and the atmospheric flow approaches at a global level. Under both approaches, the methodological and parameter updates in the 2019 Refinement (e.g., considered HWPs, starting year for carbon stocks, and conversion factors) resulted in one-third reduction in carbon removals compared to the 2006 Guidelines. The production approach leads to a systematic underestimation of global carbon stocks and removals because it confines accounting to products derived from domestic harvests and uses the share of domestic feedstock for accounting. The 2013 Guidance and the 2019 Refinement reduce the estimated global carbon removals under the production approach by 15% and 45% (2018), respectively, compared to the 2006 Guidelines. Conclusions: Gradual refinements in the IPCC default methods have a considerably higher impact on global estimates of HWP carbon stocks and removals than the differences in accounting approaches. The methodological improvements in the 2019 Refinement halve the global HWP carbon removals estimated in the former version, the 2006 Guidelines. [ABSTRACT FROM AUTHOR]

Background: British Columbia's (BC) extensive forest resources provide climate change mitigation opportunities that are available to few other jurisdictions. However, as a consequence of the Mountain Pine Beetle outbreak and large-scale wildfires, BC is anticipating reduced roundwood harvest for the next decades. Progress towards more climatically efficient utilization of forest resources is needed. This research quantitatively compared the greenhouse gas emission consequences of nine harvested wood products trade and consumption strategies. Inward-focused strategies use wood products within Canada to achieve emission reduction objectives, while outward-focused strategies encourage exports of wood products. Results: In the business-as-usual baseline scenario, average emissions arising from BC-originated harvested wood products between 2016 and 2050 were 40 MtCO2e yr−1. The estimated theoretical boundaries were 11 MtCO2e yr−1 and 54 MtCO2e yr−1, under the scenarios of using all harvests for either construction purposes or biofuel production, respectively. Due to the constrained domestic market size, inward-focused scenarios that were based on population and market capacity achieved 0.3–10% emission reductions compared to the baseline. The international markets were larger, however the emissions varied substantially between 68% reduction and 25% increase depending on wood products' end uses. Conclusions: Future bioeconomy strategies can have a substantial impact on emissions. This analysis revealed that from a carbon storage and emission perspective, it was better to consume BC's harvests within Canada and only export those products that would be used for long-lived construction applications, provided that construction market access beyond the US was available. However, restricting export of wood products destined for short-lived uses such as pulp and wood pellets would have significant economic and social impacts. On the other hand, inward-focused strategies had a small but politically and environmentally meaningful contribution to BC's climate action plan. This study also revealed the conflicts between a demand-driven bioeconomy and targeted environmental outcomes. A hierarchical incentive system that could co-exist with other market drivers may help achieve emission reduction goals, but this would require a better quantitative understanding of wood products' substitution effects. While the analyses were conducted for BC, other regions that are net exporters of wood products may face similar issues. [ABSTRACT FROM AUTHOR]

Several laboratory studies and experiments have demonstrated the usability of polymer films filled with electrically conductive filler as piezoresistive material. Applied to adhesives, the glue lines of wood products can achieve multifunctional—thus bonding and piezoresistive/strain sensing—properties. Based on critical load areas in timber constructions, upscaled test setups for simplified load situations were designed, especially with regard to a stress-free electrical contact. In a second step, another upscaling was done to small glulam beams. Based on an experimental test sequence, the piezoresistive reactions as well as the behaviour until failure were analysed. The results show in all cases that a piezoresistive reaction of the multifunctionally bonded specimens was measurable, giving a difference in the extent of relative change. Additionally, measured phenomena like inverse piezoresistive reactions, electrical resistance drift and the absence of a piezoresistive reaction were discussed, based on additional strain analysis by digital image correlation. A model of macroscopic and microscopic strains influencing the piezoresistive reaction of the electrically conductive bond line in wood was used to explain all experimental results. Finally, a first scale-up of piezoresistive bond lines from laboratory samples to glulam beams was possible and successful. [ABSTRACT FROM AUTHOR]