Durability Of Wood Research Articles

Preparation and Characterization of Heat-Treated Douglas Fir Wood with Core–Shell Structure

Wood heat treatment has been generally accepted as an effective wood modification technology as it improves the dimensional stability and biological durability of wood. However, the property improvements are obtained at the cost of reduced mechanical properties. In this study, heat-treated Douglas fir wood with thermally modified shell and unchanged inner core was prepared by surface heating to make possible the broader applications of heat-treated wood. Colour comparison, dynamic vapor sorption and dynamic mechanical analysis were performed to characterize the physico-mechanical performance of the shell and core of the treated wood. The results reveal a darkened, hydrophobic and rigid shell and a barely changed inner core. X-ray photoelectron spectroscopy shows pronounced degradation of polysaccharides in the surface layer. In contrast, the relative contents of different carbon components in the core layer are similar to that of the untreated wood, indicating the reason for the performance difference between the shell and the core of the treated wood. The initial wood moisture content plays an important role in controlling the temperature gap between the core and the shell during treatment and can be used as a key parameter to adjust the structure and performance of the heat-treated wood.

Evaluating the cascading‐use of wood furniture: How value‐retention processes can contribute to material efficiency and circularity

AbstractAs utilized technical products, durable wood furniture plays an important role in a future circular economy (CE). However, contemporary CE literature predominantly focuses on wood's biochemical properties and its potential as a consumable material within the bio‐cycle. This perspective prevents meaningful consideration of CE strategies for the wood products sector, particularly for value‐retention processes (VRPs), including reuse, repair, and refurbishment. We adapt and apply the VRP model introduced by the UN International Resource Panel (IRP) to wood furniture products to quantify select environmental benefits made possible through cascading‐use, via VRPs (vs. new manufacturing). Unlike traditional life cycle assessment (LCA), this model accounts for impacts incurred and avoided through product life‐extension and VRPs, relative to conventional systems of new manufacturing, disposal, and replacement. Three case studies of wood‐based chairs are conducted to demonstrate this new application of the VRP model to compare the relative environmental impacts associated with wood furniture that is diverted to cascading‐use, prior to recycling. In collaboration with industry partners, new material requirements (kg/unit), energy requirements (kWh/unit), emissions (kg CO2‐e./unit), and waste generation (kg/unit) were calculated for newly manufactured chairs (OEM new) and subsequent cascading‐use via reuse, repair, and refurbishment. The differing degrees of environmental impact avoidance and material efficiency are presented for each case study product and VRP, to provoke discussion and future research regarding the effective and optimal utilization of technical, durable wooden furniture within a CE.

Spread, Vector Flight Behavior, and Impact of Laurel Wilt in Sassafras Beyond the Gulf-Atlantic Coastal Plain

Abstract Laurel wilt is a destructive vascular disease of trees in the laurel family (Lauraceae) caused by a nonnative insect/pathogen complex. This study monitored the recent spread and impact of laurel wilt in sassafras (Sassafras albidum [Nutt.] Nees) from the Gulf-Atlantic Coastal Plain region of the southeastern United States (US) into the adjacent Piedmont/Sandhills and Mountain regions. Laurel wilt was detected at thirteen of forty-six sassafras sites including seven outside the Coastal Plain. Compared to nondiseased sites, sassafras mortality due to laurel wilt increased rapidly from 2018 to 2020 and occurred in all diameter classes monitored (≥ 5 cm diameter at breast height, dbh). Flight trapping for the laurel wilt vector, the redbay ambrosia beetle (RAB, Xyleborus glabratus Eichhoff), with α-copaene lures did not enhance early detection of latent laurel wilt infections. Seasonal flight activity of the RAB in the Piedmont and Mountains suggested two generations per year with little to no flight from December through March. Study Implications Sassafras is the most widely-distributed lauraceous tree species in the US and is valued for its ecological functions, durable wood, and numerous cultural uses. Our results strongly suggest the potential for substantial loss of the existing sassafras resource as laurel wilt continues spreading through the eastern US. Survey traps baited with current lures for the primary insect vector are unlikely to improve early detection of new laurel wilt infections. The georeferenced network of plots established for this project provides baseline data for future monitoring efforts and could be revisited to look for evidence of sassafras resistance to the laurel wilt pathogen.

Chemical and structural changes of ocote pine (Pinus oocarpa) wood caused by thermal modification

Thermal modifications alter the physical properties and improve the natural durability of wood without using chemical impregnation processes being an environmentally friendly alternative; these improvements could be made due to changes in the internal wood structure. In this investigation, changes caused to the chemical composition and microstructure of wood Pinus oocarpa by thermal modification at 170 and 190 °C were evaluated. The thermal treatment was carried out in a prototype chamber operated during the modification steps under a steam atmosphere, with a continuous flow without pressure. The evaluation of chemical changes was performed following the TAPPI standards. Using Fourier transform infrared spectroscopy (FTIR) and optical microscopy, the wood microstructure was characterized. The results showed a decrease in holocellulose contents by 7% at 170 °C and by 9% at 190 °C; lignin contents increased at 170 °C (6%) and at 190 °C (8%) and extractives were increased by 8% (170 °C) and 13% (190 °C); the changes obtained by the spectra were related to the C-H deformation in cellulose and hemicelluloses and the complex bonds of lignin carbohydrates of the -CH3 (lignin) and CH2 (carbohydrates) groups and organic acids released during thermal modification. Thickness of tracheid walls decreased in earlywood 8% (170 °C) and 22% (190 °C) and in latewood 11% (170 °C) and 14% (190 °C); lumen diameters increased in earlywood to 170 °C (14%) and 190 °C (48%) and in latewood in 14% (170 °C) an in 20% (190 °C). At 190 °C, the cell alterations were higher. Pinus oocarpa was thermally modified at 170 °C showing better wood quality in its internal structure.

EXPRESSION ANALYSIS OF ANTHOCYANIN BIOSYNTHETIC GENES FROM THE YOUNG AND MATURE LEAVES OF TECTONA GRANDIS L.F.

Tectona grandis L.f. is a tropical hardwood tree which is known for its timber yield. Apart from its durable wood, the leaves of teak are rich source of anthocyanin. The main objective of the present study was to analyze the expression profile of major anthocyanin biosynthetic genes from the young and mature leaves of teak. The young leaves of teak contains significant amount of anthocyanin when compared to mature leaves. The key enzyme in the anthocyanin biosynthetic pathway, PAL, the regulatory enzyme, CHI and the end point enzyme UGT showed sound activity in young leaves. The obtained results were further correlated by the higher expression profile of major anthocyanin biosynthetic genes such as CHS1, CHS2, CHI1, CHI2, F3’5’H1, F3’5’H2, DFR, ANS and UF3GT in the young leaves.

Oldestwoodenobjects.net – A Compilation of Wooden Goods with Remarkable Longevity

Abstract The website oldestwoodenobjects.net serves as a platform for the scientific community to collect, display and share early traces of wood utilization. It also serves educational purposes, to teach a wide audience about how multifunctional and durable wood can be, when wisely used. The collection of objects is large and diverse, ranging from simple tools for hunting, like spears, to musical instruments of the high culture, such as violins. The first means of transport, dugout canoes or early infrastructure, like water wells, are remarkably old. Due to weathering, early buildings or constructions are poorly or only partially preserved. But some sacred buildings that are still in use today have an impressive age. At the time of writing this manuscript, a total of 211 prehistoric and historic wooden objects from around the globe were gathered and can be compared at the online application. The oldest item on the list is from 300 000 years before present. To continue expanding the database, the community is encouraged to contribute new entries.

Wood Vault: remove atmospheric CO2 with trees, store wood for carbon sequestration for now and as biomass, bioenergy and carbon reserve for the future

BackgroundWood harvesting and storage (WHS) is a hybrid Nature-Engineering combination method to combat climate change by harvesting wood sustainably and storing it semi-permanently for carbon sequestration. To date, the technology has only been purposefully tested in small-scale demonstration projects. This study aims to develop a concrete way to carry out WHS at large-scale.ResultsWe describe a method of constructing a wood storage facility, named Wood Vault, that can bury woody biomass on a mega-tonne scale in specially engineered enclosures to ensure anaerobic environments, thus preventing wood decay. The buried wood enters a quasi-geological reservoir that is expected to stay intact semi-permanently. Storing wood in many environments is possible, leading to seven versions of Wood Vault: (1) Burial Mound (Tumulus or Barrow), (2) Underground (Pit, Quarry, or Mine), (3) Super Vault, (4) Shelter, (5) AquaOpen or AquaVault with wood submerged under water, (6) DesertOpen or DesertVault in dry regions, (7) FreezeVault in cold regions such as Antarctica. Smaller sizes are also possible, named Baby Vault. A prototype Wood Vault Unit (WVU) occupies 1 hectare (ha, 100 m by 100 m) of surface land, 20 m tall, stores up to 100,000 m3 of wood, sequestering 0.1 MtCO2. A 1 MtCO2 y−1 sequestration rate can be achieved by collecting currently unused wood residuals (WR) on an area of 25,000 km2, the size of 10 typical counties in the eastern US, corresponding to an average transportation distance of less than 100 km. After 30 years of operation, such a Wood Vault facility would have sequestered 30 MtCO2, stored in 300 WVUs, occupying a land surface of 300 ha. The cost is estimated at $10–50/tCO2 with a mid-point price of $30/tCO2. To sequester 1 GtCO2 y−1, wood can be sourced from currently unexploited wood residuals on an area of 9 Mkm2 forested land (9 million square kilometers, size of the US), corresponding to a low areal harvesting intensity of 1.1 tCO2 ha−1 y−1. Alternatively, giga-tonne scale carbon removal can be achieved by harvesting wood at a medium harvesting intensity of 4 tCO2 ha−1 y−1 on 3 Mkm2 of forest (equivalent to increasing current world wood harvest rate by 25%), or harvest on 0.8 Mkm2 forest restored from past Amazon deforestation at high harvest intensity, or many combinations of these and other possibilities. It takes 1000 facilities as discussed above to store 1 GtCO2 y−1, compared to more than 6000 landfills currently in operation in the US. After full closure of a Wood Vault, the land can be utilized for recreation, agriculture, solar farm, or agrivoltaics. A more distributed small operator model (Baby Vault) has somewhat different operation and economic constraints. A 10 giga-tonne sequestration rate siphons off only 5% of total terrestrial net primary production, thus possible with WHS, but extreme caution needs to be taken to ensure sustainable wood sourcing.ConclusionsOur technical and economic analysis shows that Wood Vault can be a powerful tool to sequester carbon reliably, using a variety of wood sources. Most pieces of the technology already exist, but they need to be put together efficiently in practice. Some uncertainties need to be addressed, including how durability of buried wood depends on detailed storage methods and burial environment, but the science and technology are known well enough to believe the practicality of the method. The high durability, verifiability and low-cost makes it already an attractive option in the current global carbon market. Woody biomass stored in Wood Vaults is not only a carbon sink to combat current climate crisis, but also a valuable resource for the future that can be used as biomass/bioenergy and carbon supply. The quantity of this wood utilization can be controlled carefully to maintain a desired amount of CO2 in the atmosphere to keep the Earth’s climate from diving into the next ice age, acting as a climate thermostat. The CO2 drawdown time is on the order of 100 years while the ramp-up time is a decade. A sense of urgency is warranted because the CO2 removal rate is limited by biosphere productivity, thus delayed action means a loss of opportunity. In conclusion, WHS provides a tool for managing our Earth system, which will likely remain forever in the Anthropocene.

Durability and Moisture Dynamics of Douglas-Fir Wood From Slovenia.

Wood in outdoor applications is subject to various decomposition factors. Wood degradation can be prevented by construction details, biocide protection of wood, wood modification or selection of naturally durable species. Unfortunately, most species in Europe do not have naturally durable wood. Imported tree species represent a new pool from which we can draw wood species with better natural durability and better resilience towards climate change. The performance of wood when used outdoors depends on the biologically active compounds (extractives) and the water exclusion efficacy. Considering decay, presence of biologically active compounds and water exclusion efficacy, we can estimate the density, modulus of elasticity, extractive content and resistance dose, which reflects the material properties of wood. Recently, the most commonly used model for this purpose is Meyer-Veltrup. Literature data indicate that the durability of the wood from native and new sites is not always comparable, so it is necessary to determine the resistance of non-native wood species from new sites. This paper presents original data on the wood’s overall durability from American Douglas fir (Pseudotsuga menziesii) grown in Slovenia. Experimental data show that the mature heartwood of Douglas fir is more durable than the wood of European larch (Larix decidua). Durability can be attributed to good water exclusion efficacy and inherent durability. Inherent durability is primarily the result of the high content of extractives. Based on the results, it can be concluded that American Douglas fir grown in Central Europe has a high potential for outdoor use.

Influences of extractives and thermal modification on the UV resistance of Albizia lebbeck wood

ABSTRACT Thermal modification is a chemical-free process for improving hydrophobicity, dimensional stability, and biological durability of wood. There are inconsistent reports on the UV resistance of thermally modified wood with the majority of studies indicating its vulnerability to UV degradation. This may be due to the natural variability of chemical constituents, particularly extractives, in different wood species. In this study, the UV resistance of sapwood and heartwood of Albizia lebbeck was evaluated to elucidate the role of extractives on photo-stabilisation. A comparison between the extractive rich untreated and heat-treated sapwood and heartwood was carried out. UV resistance was evaluated by exposing modified wood to UV light in an accelerated weathering tester. Untreated sapwood attained dark colour (photoyellowing) upon UV light exposure, whereas thermally modified sapwood showed contrasting behaviour (lightening). Untreated heartwood showed more resistance to photodegradation. Thermally modified heartwood retained its colour for a considerable extent and exhibited good UV resistance than the untreated samples. Results indicate that extractives present in the heartwood of A. lebbeck act as UV absorber to impart substantial UV stability to wood. Furthermore, the enhanced UV resistance of heat-treated heartwood could be due to the accumulation of photostable compounds evolved during the thermal modification of wood.

Combining mineralisation and thermal modification to improve the fungal durability of selected wood species

The development of non-biocidal and environmentally friendly systems to protect wood against biological decay has become a high priority in recent years. In the present study the impact of an innovative modification procedure, combining two environmentally friendly modification methods: thermal modification and mineralisation, using an aqueous solution of calcium acetoacetate as a precursor, on the fungal durability of wood was evaluated. European beechwood (Fagus sylvatica) and Norway sprucewood (Picea abies) were selected as model wood species. Wood samples were treated using either a single or combination of both methods and exposed to four different fungi: Gloeophyllum trabeum, Rhodonia placenta, Trametes versicolor and Pleurotus ostreatus. The effect of the different modifications on moisture content, dynamic vapour sorption, contact angle and pH value was also evaluated. Overall, the highest durability against Rhodonia placenta, Trametes versicolor and Pleurotus ostreatus was achieved through thermal modification in both wood species, while the combination of mineralisation and thermal modification has a synergistic effect against degradation by Gloeophyllum trabeum. In the case of beechwood the mass loss decreased from 41% for native to 6% for combined modified samples. We proved that the effectiveness of different treatment against fungal decay of wood were in strong dependence of their moisture content, dynamic vapour sorption, contact angle and pH values. The role of fungi on the morphology of the wood and on crystal structure of formed carbonate was investigated using SEM-EDS analysis.

Mahechadendron puntecascarillo (Vochysiaceae), a new genus and forest tree species from Colombia

The new genus and species Mahechadendron puntecascarillo are described based on specimens first collected in the ‘60s but only recently found with flowers and fruits. It grows in the moist forests of the Middle Magdalena River in Colombia. The highly durable wood of this forest tree species is still used intensively for construction. Morphological and rbcL sequence data place this genus in the Vochysiaceae, most likely closely related to Callisthene. Mahechadendron shows inflorescences in compound dichasia, compact, only developed laterally, traits not previously recorded in this family. Mahechadendron puntecascarillo exhibits the tiniest flowers known in the Vochysiaceae, with the fourth sepal basally sacciform, and copious villous-lanose indumentum in the internal portions of the fourth sepal, petal, filament, and ovary; the flowers also have the single petal non-clawed, a feature not very common in Vochysiaceae. In addition, the capsular fruit has a thick and persistent central column, and the exocarp is fused to the endocarp even at maturity, with seeds unilaterally winged. Moreover, this species bears mirror-image flowers, indicating enantiostyly, a sexual polymorphism already known in some Vochysiaceae. The conservation status suggested for the new species is Endangered (EN). A key to the genera of Vochysiaceae is provided.

Durability of Thermally Modified Western Hemlock Lumber Against Wood Decay Fungi

The chemical modification of wood is gaining popularity as a treatment to increase wood durability, particularly in jurisdictions where restrictions on the use of chemical impregnation are increasing. This work measures the impact of thermal modification of western hemlock lumber durability against decay fungi. Western hemlock lumber was thermally modified using a cycle with temperatures ranging from 80 to 170°C and was cut into standard 19 mm blocks for testing according to AWPA method E10. Performance of thermally modified wood was measured against two brown rot fungi, Rhodonia placenta and Gloeophyllum trabeum and one white rot fungus, Trametes versicolor over an 8, 12, and 16-week incubation period. Unmodified western hemlock wood, untreated southern pine and copper azole-treated southern pine were included for comparison. Thermal modification resulted in a slight improvement in durability against Gloeophyllum trabeum, but not Rhodonia placenta compared to untreated western hemlock which caused 50.3 and 52.2% mass loss in thermally modified western hemlock after 16 weeks, respectively. T. versicolor caused a 21.2% mass loss after 16 weeks, but this value was not statistically different than untreated western hemlock (p = 0.46). For comparison, copper azole-treated southern pine showed only an average of 0 and 15% mass loss when exposed to G. trabeum or R. placenta for 16 weeks, respectively. Together, these data indicate that while there may be some protective effect of thermally modifying western hemlock, further development of treatment processes are needed to improve the durability of thermally modified western hemlock.

Recent Developments Studies on Wood Protection Research in Academia: A Review

The wood preservation industry has taken large leaps to develop and produce chemicals that protect wood from microorganisms and weathering degradation with no or low environmental impact. These improvements occurred after concerns of federal and public agencies about the release of toxic components into atmosphere, soil, and water. These days, reduction in use of non-renewable resources is a crucial concern. Wood and wood-based products are generally low in CO2emissions and can be gained from sustainable forest resources. Therefore, they can play a significant role as renewable resources. In comparison to other building materials, wood has numerous advantages, such as suitable thermal insulation, high strength to weight ratio, easy machinability, and attractive esthetics. Wood as a valuable building and industrial material requires to be protected due to its biodegradable properties especially when it is submitted to harsh conditions. Wood durability can be improved through wood protection which include wood preservatives and modification systems. Wood protection should be safe to use, efficient, cost-effective, permanent, and should not corrode metal or degrade wood components. Numerous reviews of wood protection can be found in the scientific literatures, but until now a review of a combination of wood preservation and wood modification has not been studied. It should be considered that the latest research projects in wood protection in academia not always reflect the most current developments in the industry due to exclusive rights. The findings reported in academia contribute to the safe use of preservatives, advancement of wood modification techniques, as well as recycle and disposal of treated material. Therefore, in this study, the most current research and advancements promoted in the wood protection in academia are discussed which including an overall summary of the recent developments on wood preservatives, different types of preservatives, natural preservative compounds, and modification technologies in academia.

Experimental study on durability of wood–plastic composites by coupling dry–wet cycles and seawater environment

AbstractThe durability of wood–plastic composites (WPCs) exposed to seawater dry–wet cycles were investigated. The most detrimental cycles were evaluated by the orthogonal design method. The physical properties, structural strength, chemical characteristics, and thermal stability of WPC materials under the worst seawater dry–wet (W‐SDW) cycles were described based on discoloration/water absorption/thickness swelling, hardness/impact strength, Fourier transform infrared spectra, and thermogravimetric analysis results, respectively. The results showed that the W‐SDW cycles were: immersion temperature of 60°C, immersion time of 4 h, drying temperature of 70°C, and drying time of 3 h. The exposure to W‐SDW cycles degraded the fiber–matrix interface interaction, increasing discoloration, water absorption, and thickness swelling as well as reducing hardness, impact strength, and pyrolysis temperature. The degree of degradation of the fiber and matrix is positively correlated with that of the fiber–matrix interface interaction. The analysis of the experimental phenomenon indicates that protecting the fiber–matrix interface maintains the durability of WPC materials.

Improved Durability of Wood Treated with Nano Metal Fluorides against Brown-Rot and White-Rot Fungi

Low-water soluble metal fluorides such as magnesium fluoride (MgF2) and calcium fluoride (CaF2) were evaluated for decay protection of wood. Initially, the biocidal efficacy of nano metal fluorides (NMFs) against wood destroying fungi was assessed with an in-vitro agar test. The results from the test showed that agar medium containing MgF2 and CaF2 was more efficient in preventing fungal decay than stand-alone MgF2 or CaF2. These metal fluorides, in their nanoscopic form synthesized using fluorolytic sol-gel synthesis, were introduced into the sapwood of Scots pine and beech wood and then subjected to accelerated ageing by leaching (EN 84). MAS 19F NMR and X-ray micro CT images showed that metal fluorides were present in treated wood, unleached and leached. Decay resistance of Scots pine and beech wood treated with NMFs was tested against wood destroying fungi Rhodonia placenta and Trametes versicolor in accordance with EN 113. Results revealed that mass losses were reduced to below 3% in wood treated with the combination of MgF2 and CaF2. It is concluded that NMFs provide full protection to wood even after it has been leached and can be used as wood preservatives in outdoor environments.

Rapid Testing of Resistance of Timber to Biodegradation by Marine Wood-Boring Crustaceans.

Wood-boring invertebrates rapidly destroy marine timbers and wooden coastal infrastructure, causing billions of dollars of damage around the globe every year. As treatments of wood with broad spectrum biocides, such as creosote and chromated copper arsenate (CCA), are now restricted in marine use by legislation, naturally durable timber species and novel preservation methods of wood are required. These methods undergo testing in order to meet regulatory standards, such as the European standard for testing wood preservatives against marine borers, EN 275. Initial investigation of durable timbers species or wood preservative treatments can be achieved quickly and inexpensively through laboratory testing, which offers many advantages over marine field trials that are typically costly, long-term endeavours. Many species of Limnoria (gribble) are marine wood-boring crustaceans. Limnoria are ideal for use in laboratory testing of biodegradation of wood by marine wood-borers, due to the practicality of rearing them in aquaria and the ease of measuring their feeding rates on wood. Herein, we outline a standardizable laboratory test for assessing wood biodegradation using gribble.

Ecotoxic, genotoxic, and cytotoxic potential of leachate obtained from chromated copper arsenate-treated wood ashes.

Preservative treatments increase the durability of wood, and one of the alternative treatments involves the use of chromated copper arsenate (CCA). Due to the toxicity of CCA, the disposal of CCA-treated wood residues is problematic, and burning is considered to provide a solution. The ecotoxicological potential of ash can be high when these components are toxic and mutagenic. The aim of this study was to evaluate the toxicity and genotoxicity of bottom ash leachates originating from CCA-treated wood burning. Physical-chemical analysis of the leachates revealed that in treated wood ashes leachate (CCA-TWBAL), the contents of arsenic and chromium were 59.45 mg.L-1 and 54.28 mg.L-1, respectively. In untreated wood ashes leachate (UWBAL), these contents were 0.70 mg.L-1 and 0.30 mg.L-1, respectively. CCA-TWBAL caused significant toxicity in Lactuca sativa, Allium cepa, and microcrustacean Artemia spp. (LC50 = 12.12 mg.mL-1). Comet assay analyses using NIH3T3 cells revealed that concentrations ranging from 1.0 and 2.5 mg.mL-1 increase the damage frequency (DF) and damage index (DI). According to MTT assay results, CCA-TWBAL at concentrations as low as 1 mg.mL-1 caused a significant decrease in cellular viability. Hemolysis assay analyses suggest that the arsenic and chromium leachate contents are important for the ecotoxic, cytotoxic, and genotoxic effects of CCA-TWBAL.

Investigations of the Chemical Distribution in Sorbitol and Citric Acid (SorCA) Treated Wood—Development of a Quality Control Method on the Basis of Electromagnetic Radiation

Recent studies showed treatments with sorbitol and citric acid (SorCA) to significantly improve the dimensional stability and biological durability of wood. The industrialization of this process requires a quality control (QC) method to determine if the fixated chemicals are homogenously distributed within the piece of wood, which is essential for uniform material performance. Therefore, the objective of this work was to evaluate the use of common electromagnetic radiation-based methods to determine the degree of modification in SorCA-treated wood. Both Fourier transform infrared (FTIR) spectroscopy and near-infrared (NIR) spectroscopy have been used to create rough calibrations for the weight percent gain (WPG) prediction models. The FTIR measurements resulted in a high linear correlation between the band area ratio (BAR) and the WPG (R2 = 0.93). Additionally, a partial least square (PLS) regression of NIR spectroscopic data resulted in a model with a high prediction power (R2 = 0.83). Furthermore, X-ray density profiling emerged as a simple alternative for the QC by showing a gradient of modification chemicals inside the sample and differences in chemical uptake between earlywood and latewood. Overall, it can be concluded that the results from FTIR, NIR and X-ray densitometry can serve as indicators of impregnation chemical distribution in SorCA-modified wood.

Environmental and economic assessment of using wood to meet Paris Agreement greenhouse gas emission reductions in Slovenia

More than one hundred ninety nations, including the European Union, have signed the Paris Agreement to limit the temperature increase to 1.5 °C above pre-industrial levels. Meeting these conditions requires a steep decline in greenhouse gas (GHG) emissions by the year 2030 and zero GHG emissions by 2050. In this study, we investigated the role that wood products can play within Slovenia to reach the 2030 goal of a 55 % reduction in GHG, as compared to 1990 levels. Slovenia, with over 58 % forest cover, is well-positioned to utilize wood products to meet these climate goals. However, questions exist on how increased tree harvesting and local production, and the use of wood products contribute to replacing fossil-based materials and to lower lowering GHG emissions. To better understand the importance of wood products to GHG emission reduction, this study aimed to present a model showing how the forest-based value chain (including construction) could help reach the Paris Agreement goals. We investigated the associated environmental impacts and their related economic costs. The results indicated that Slovenia could reach the 55 % GHG emission reduction goal within 2030 through increasing tree harvesting and using these resources to increase the number of durable wood products produced within Slovenia that store carbon for long periods and substitute for other high GHG emitting materials. However, realizing these potential reductions would rely on the building industry within Slovenia to replace fossil- and mineral-based materials with wood products.

KETAHANAN ALAMI KAYU HIBRID AKASIA (Acacia mangium × A. auriculiformis) TERHADAP SERANGAN RAYAP KAYU KERING (Cryptotermes cynocephalus Light.)

Development of Acacia hybrid is important to be done due to their superiority such as high productivity, good wood quality, more tolerance to pest/disease and adaptive to marginal sites, although its wood durability to wood-destroyer organism attacks is still unknown yet. This study aimed to observe the wood natural durability of Acacia hybrid to drywood termites (Cryptotermes cynocephalus Light.) attack. The wood samples used were taken from 6 years old trees of Acacia hybrid in Wonogiri, Central Java. The experimental design used is completely randomized design using two factors, axial and radial of wood section with the number of trees as replication.Parameters measured were extractive content, termite mortality and wood mass loss.The results showed that the axial section of wood significantly affected the wood extractive content at the level of 0.01, while termite mortality and the mass loss of wood were not significantly affected by the wood section. The largest average percentages of termite mortality and mass loss of wood found on the middle of wood section (96.67%) and near the bark (1.14%) respectively. Based on this result, the Acacia hybrid wood is categorized as very durable wood and potential to be developed as raw material for solid wood-based industries