Search Results (49)

Copal is a non-timber forest product of historical, cultural, and industrial significance in Mexico. The use of unsustainable harvesting methods and a lack of understanding of the factors influencing their production have led to a decline in natural populations of resin-producing species. This study aimed to identify the dendrometric, edaphoclimatic, physiological, and resin extraction method variables with the greatest influence on resin yield in Bursera bipinnata using correlation analysis and multiple linear regression. The research was conducted in the Los Sauces micro-watershed, Morelos, Mexico, with a randomly selected sample of 70 trees. Nineteen explanatory variables were categorized into dendrometric, edaphoclimatic, physiological, and extraction method parameters. Variables significantly correlated with resin yield were diameter at breast height, crown diameter, crown volume, altitude, resin tapping faces on the stem, resin tapping faces on branches, total resin tapping faces, resin tapping face height, total resin tapping area, and the Normalized Difference Moisture Index (NDMI) in October. The regression model revealed that resin yield increased significantly with total tapping area ($\beta =0.649$) but decreased with greater incision length ($\beta =-0.308$) and higher NDMI values in October ($\beta =-0.205$), explaining 43.8% of the variation in resin yield. Results highlight the importance of tissue damage intensity, tree physiological status, and water availability as determinants of resin production. The model provides practical guidelines for optimizing extraction techniques, enabling sustainable harvesting that maintains tree vitality and supports long-term productivity in resin-harvesting communities. Full article

With the aim of reducing the environmental impact of buildings, the appropriate selection of building materials is essential, as a building is a complex system composed of various materials. With this background, a multi-criteria decision-making approach has recently gained traction. This study demonstrated the effect of building material selection on both environmental and economic parameters of a building in the context of Japan. A comparative analysis of five structural frame options was conducted utilizing a reference building model to assess the implication of material choices. The findings indicated that wooden frame options are advantageous in environmental aspects compared to non-wooden frames, provided that sustainable forestry practices and appropriate recycling scenarios are implemented. Conversely, it was found that a Cross Laminated Timber (CLT) frame is the most expensive option. This suggests that a hybrid approach, which combines various frame materials, could yield a more effective solution in terms of both environmental and economic sustainability. In addition, it was highlighted that building envelopes, such as foundation, exterior wall, and roof, should be prioritized to enhance the sustainability of a building from a material perspective. Furthermore, gypsum board, commonly used for sheathing building elements, should be selected with careful consideration of its environmental impact. Full article

Cross-Laminated Timber (CLT) is ideal for tall timber structures but relies on environmentally concerning chemical adhesives. Nailed Cross-Laminated Timber (NCLT) offers a sustainable alternative by using densified wooden nails that form eco-friendly, adhesive-free bonds through lignin’s thermoplastic properties. However, significant uncertainties remain regarding the synergistic effects of multiple wooden nails. To address this, this study systematically analyzed the impact of the group effect on the mechanical performance of wooden nail joints. The results show that within the elastic range, the number of wooden nails has no significant effect on the elastic behavior of a structure. However, it is significantly positively correlated with both the joint yield load and yield displacement, enabling the accurate prediction of the structural yield point based on the number of wooden nails. With consistent nail arrangements, the group effect coefficient for the load-bearing capacity remains highly stable and shows no significant correlation with the number of nails. Additionally, an increase in the number of wooden nails significantly enhances the deformation resistance and structural stiffness, while having a minimal impact on ductility. This study reveals the linear additive nature of the group effect in wooden nails, providing important theoretical support for the design of NCLT. Full article

Pollarding is an ancient agroforestry practice that greatly contributes to the sustainability of farming but is slowly becoming extinct because traditional pollards are not viable from a financial and social viewpoint. In particular, the cutting of pollards is too slow, expensive and dangerous for modern farmers to apply. This study presents the first test of mechanized pollarding, performed with two different devices: a set of shears and a disc saw. Both devices were fitted to the boom tip of a tracked excavator and were tested on poplar rows in a typical alley-cropping system. The introduction of those simple devices restored productivity and safety to pollarding as a modern practice. Tree topping incurred a cost around 1 € tree⁻¹, or 250–350 € ha⁻¹. This cost would need to be balanced against the revenue obtained from the treetops sold as biomass and the increased yields of the alley crop, prolonged for several years. Mechanization also allows cutting the treetops several metres above ground level, so that the trunks of the pollarded trees may yield valuable timber when they are eventually harvested. Full article

This study investigates the impact of China’s Collective Forest Tenure Reform (CFTR) on forest carbon sequestration efficiency and rural household income, two critical indicators of ecological sustainability and economic development. Using a difference-in-differences (DID) approach, the study analyzes data from 31 provinces between 1997 and 2014. The results indicate that CFTR significantly enhances forest carbon sequestration efficiency through land use optimization and industrial structure upgrading. Moreover, the reform positively influences rural household income by increasing timber yield and facilitating labor mobility. The study also explores the heterogeneity of these impacts across regions, income levels, carbon sequestration efficiency levels, and carbon trading pilot areas. These findings provide valuable insights for policymakers aiming to balance ecological sustainability and economic growth through targeted forestry management strategies. Full article

The building and construction sector accounts for nearly 40% of global greenhouse gas emissions, with steel-framed buildings being a significant contributor due to high CO₂ emissions during production. To mitigate this issue, integrating Cross-Laminated Timber (CLT) into structural systems has emerged as a sustainable alternative. CLT, known for its carbon sequestration properties, offers an environmentally friendly replacement for reinforced-concrete slabs, particularly when paired with steel structures to enhance material reuse and reduce lifecycle impacts. This study focuses on hybrid systems combining H-shaped steel beams and CLT floor panels connected using high-strength friction bolts. A four-point bending test, simulating a secondary beam, was conducted, demonstrating that the composite effect significantly enhances flexural stiffness and strength. Additionally, a simplified method for evaluating the flexural stiffness and yielding strength of these composite beams, based on material and joint properties, was shown to successfully evaluate the test results. Full article

Loblolly pine plantations have long been cultivated primarily for timber production due to their rapid growth and economic value. However, these forests are now increasingly acknowledged for their important role in mitigating climate change. Their dense canopies and fast growth rates enable them to absorb and store substantial amounts of atmospheric carbon dioxide. By integrating sustainable management practices, these plantations can maximize both timber yield and carbon sequestration, contributing to global efforts to reduce greenhouse gas emissions. Balancing timber production with vital ecosystem services, such as carbon storage, demands carefully tailored management strategies. This study examined how the timing of thinning—specifically early thinning at 17 years and late thinning at 32 years—impacts biomass accumulation, carbon storage capacity, and carbon sequestration rates in loblolly pine plantations located in northern Iran. Two thinning intensities were evaluated: normal thinning (removal of 15% basal area) and heavy thinning (removal of 35% basal area). The results demonstrated that thinning significantly improved biomass, sequestration rates and carbon storage compared to unthinned stands. Early thinning proved more effective than late thinning in enhancing these metrics. Additionally, heavy thinning had a greater impact than normal thinning on increasing biomass, carbon storage, and sequestration rates. In early heavy-thinned stands, carbon storage reached 95.8 Mg C/ha, which was 63.0% higher than the 58.8 Mg C/ha observed in unthinned 32-year-old stands. In comparison, early normal thinning increased carbon storage by 41.3%. In late heavy-thinned stands, carbon storage reached 199.4 Mg C/ha, which was 29.0% higher than in unthinned stands of the same age (154.6 Mg C/ha at 52 years). In contrast, late normal thinning increased carbon storage by 13.3%. Similarly, carbon sequestration rates in unthinned stands were 1.84 Mg C/ha/yr at 32 years and 2.97 Mg C/ha/yr at 52 years. In comparison, 32-year-old stands subjected to normal and heavy thinning had sequestration rates of 2.60 and 2.99 Mg C/ha/yr, respectively, while 54-year-old normally and heavily thinned stands reached 3.37 and 3.83 Mg C/ha/yr, respectively. The highest carbon storage was concentrated in the stems for 52–58% of the total. Greater thinning intensity increased the proportion of carbon stored in stems while decreasing the contribution from foliage. These results indicate that heavy early thinning is the most effective strategy for maximizing both timber production and carbon sequestration in loblolly pine plantations. Full article

Southern U.S. forests are essential for carbon storage and timber production but are increasingly impacted by natural disturbances, highlighting the need to understand their dynamics and recovery. Canopy cover is a key indicator of forest health and resilience. Advances in remote sensing, such as NASA’s GEDI spaceborne LiDAR, enable more precise mapping of canopy cover. Although GEDI provides accurate data, its limited spatial coverage restricts large-scale assessments. To address this, we combined GEDI with Synthetic Aperture Radar (SAR), and optical imagery (Sentinel-1 GRD and Landsat–Sentinel Harmonized (HLS)) data to create a comprehensive canopy cover map for Florida. Using a random forest algorithm, our model achieved an R² of 0.69, RMSD of 0.17, and MD of 0.001, based on out-of-bag samples for internal validation. Geographic coordinates and the red spectral channel emerged as the most influential predictors. External validation with airborne laser scanning (ALS) data across three sites yielded an R² of 0.70, RMSD of 0.29, and MD of −0.22, confirming the model’s accuracy and robustness in unseen areas. Statewide analysis showed lower canopy cover in southern versus northern Florida, with wetland forests exhibiting higher cover than upland sites. This study demonstrates the potential of integrating multiple remote sensing datasets to produce accurate vegetation maps, supporting forest management and sustainability efforts in Florida. Full article

The present study explored the extraction of cellulose from forest residues of four timber species, namely Cedrela montana Moritz ex Turcz, Buddleja incana Ruiz & Pav, Vallea stipularis L. f. and Myrsine andina (Mez) Pipoly, in the high montane forest of Chimborazo province, Ecuador, for the sustainable utilization of leaves, branches, and flowers. An alkaline extraction method was used on the residues without the need for prior degreasing. An ANOVA analysis was applied to evaluate significant differences in cellulose extraction yields among the species’ residues. The characterization techniques used were Fourier transform infrared spectroscopy (FTIR) and polarized light optical microscopy, which confirmed the successful extraction of cellulose with characteristics comparable to standard cotton cellulose and other traditional species. The results showed significant variations in cellulose yield among the species, with Vallea stipularis L. f achieving the highest yield of 80.83%. The crystallinity of the samples was clearly evidenced by the polarity of the light in the samples during microscopy, demonstrating that the residues can be a viable and sustainable source of cellulose, contributing to a circular economy and reducing the environmental impact of forest waste. Full article

Poplars are crucial for timber supply and ecological protection in China. Enhancing the growth of poplar plantations and improving soil fertility in arid, and semi-arid poor soil regions are key aspects of sustainable forest management. Fertilization (FTL) and drip irrigation (DI) are among the most widely used methods globally for increasing yield and soil productivity. This study conducted field experiments on FTL and DI in a 10-year-old Populus × canadensis ‘Zhongliao 1’ (cultivation varieties of P. canadensis in northern China) plantation. DI limits were set according to soil moisture at 60% (S1), 70% (S2), and 80% (S3) of field capacity; nitrogen FTL rates were set at 100% of the baseline fertilization amount (100% BFA, N 643.20 g·year⁻¹, P 473.37 g·year⁻¹, and K 492.29 g·year⁻¹) (F1), 70% BFA (F2), 130% BFA (F3), and 160% BFA (F4). The treatments of drip irrigation and fertigation (DIF) were H1 (100% BFA, 60% FC), H2 (100% BFA, 80% FC), H3 (160% BFA, 60% FC), and H4 (160% BFA, 80% FC), along with a control group (CK) without any management, totaling 12 experimental combinations. The results showed that the H4 had the most significant promoting effect on the height, DBH, and volume increments. All treatments had little effect on the soil bulk density of the plantation but significantly impacted soil capillary porosity and pH. Compared to DI, soil nutrient and organic matter content were more sensitive to FTL. Appropriate FTL and DI can increase soil sucrase activity. Soil urease activity tended to increase with higher FTL rates, and higher DI levels also positively influenced urease activity. Excessive or insufficient soil moisture and nutrients negatively impacted soil cellulase and catalase activities. Correlation analysis revealed no significant correlation between the growth of P. × canadensis ‘Zhongliao 1’ and soil nutrient content, but significant or highly significant correlations existed between growth and soil porosity and related enzyme activities. Comprehensive evaluation using a membership function indicated that high FTL levels (F4) were more conducive to the simultaneous improvement of the growth and soil fertility of the plantation, followed by H4 and F1, suggesting that high FTL is the key factor affecting the growth of 10-year-old P. × canadensis ‘Zhongliao 1’ plantations and the restoration of stand productivity, with moisture being secondary. Full article

The Amazon region contains numerous areas dedicated to sustainable timber extraction. This operation has low yields and generates a large amount of waste. However, this waste can be repurposed for energy generation, providing income for locals and reducing reliance on non-renewable energy sources prevalent in the region. This study aimed to assess the impact of torrefaction on various wood residues for briquette production. Wood residues from Mimosa scabrella Benth (Bracatinga), Dipteryx odorata (Aubl.) Willd. (Cumaru), and Aspidosperma populifolium A.DC. (Peroba mica) were torrefied at temperatures ranging from 180 to 220 °C for sixty minutes under a nitrogen atmosphere. Briquettes were produced using laboratory equipment with loading pressures between 7 and 14 MPa. Torrefied particle properties were evaluated based on proximate composition and calorific value tests, while briquette quality was assessed for physical and mechanical properties. The results demonstrated the briquetting potential of different wood species before and after torrefaction, with optimal outcomes achieved by torrefaction at 220 °C due to its enhancement of energy density. Briquettes showed optimal characteristics at compression pressures of 14 MPa, resulting in increased density (between 1.10 and 1.24 g·cm⁻³) and compression strength (between 7.20 and 21.02 MPa). The ash values were low and met the requirements. The utilization of waste for briquette production offers a significant alternative for energy generation in economically disadvantaged communities, while also enabling the replacement of non-renewable energy sources. Full article

The integral role of wild fungi in ecosystems, including provisioning, regulating, cultural, and supporting services, is well recognized. However, quantifying and predicting wild mushroom yields is challenging due to spatial and temporal variability. In Mediterranean forests, climate-change-induced droughts further impact mushroom production. Fungal fruiting is influenced by factors such as climate, soil, topography, and forest structure. This study aims to quantify and predict the mycological potential of Lactarius deliciosus in sustainably managed Mediterranean pine forests using machine learning models. We utilize a long-term dataset of Lactarius deliciosus yields from 17 Pinus pinaster plots in Soria, Spain, integrating forest-derived structural data, NASA Landsat mission vegetation indices, and climatic data. The resulting multisource database facilitates the creation of a two-stage ‘mycological exploitability’ index, crucial for incorporating anticipated mycological production into sustainable forest management, in line with what is usually done for other uses such as timber or game. Various Machine Learning (ML) techniques, such as classification trees, random forest, linear and radial support vector machine, and neural networks, were employed to construct models for classification and prediction. The sample was always divided into training and validation sets (70-30%), while the differences were found in terms of Overall Accuracy (OA). Neural networks, incorporating critical variables like climatic data (precipitation in January and humidity in November), remote sensing indices (Enhanced Vegetation Index, Green Normalization Difference Vegetation Index), and structural forest variables (mean height, site index and basal area), produced the most accurate and unbiased models (OA_training = 0.8398; OA_validation = 0.7190). This research emphasizes the importance of considering a diverse array of ecosystem variables for quantifying wild mushroom yields and underscores the pivotal role of Artificial Intelligence (AI) tools and remotely sensed observations in modeling non-wood forest products. Integrating such models into sustainable forest management plans is crucial for recognizing the ecosystem services provided by them. Full article

The current challenges facing large-diameter timber forests include low yield and low eco-economic benefit. As a result, the development of large-diameter timber forests has become one of the most important strategies for the development of forestry in China. The present study employed bibliometric analysis and Citespace software v.6.1.R3 to examine the literature from CNKI and WOS databases spanning 2002–2021. This analysis aimed to identify the research hotspots and trends in large-diameter timber trees while providing theoretical support and guidance for developing large-diameter timber forests. The research results showed the following data. (1) The number of articles published increased year by year, approximately 4.8 times in 20 years. (2) The journal “Forest Ecology and Management”, where the number of papers is up to 53, has a significant impact on the field of large-diameter timber research. The Tropical Forestry Experimental Center of the Chinese Academy of Forestry and the Wageningen University and Research in the Netherlands possess strong research capabilities, with average citation frequencies of the articles of 26.8 and 51.5, respectively. (3) Research on large-diameter trees focuses on “large-diameter timber cultivation technology and cultivation measures”, “forest conservation management”, “large-diameter timber stand structure”, and “dynamic monitoring of large-diameter timber growth”. “Selection of suitable seed sources”, “Innovation of large-diameter timber cultivation technology”, and “improvement of large-diameter timber forest management mode” are the future research trends of large-diameter trees. In the future, it will be a challenge to realize the sustainable development of large-diameter timber resources. Concurrently, long-term monitoring and scientific management of large-diameter timber forests will be a key issue in promoting the development of large-diameter timber forests. Full article

Despite the increasing popularity of glamping structures, empirical studies often overlook the carbon impact of wood in these constructions, creating a significant research gap. Understanding the net carbon effect of wood in glamping structures is crucial for informing sustainable building practices. This paper aims to quantitatively compare the net carbon impact of wood in glamping structures, filling a notable gap in the current research literature. The investigation undertakes a thorough evaluation employing a life cycle methodology, appraising the emissions linked with the complete glamping life span. Seven Romanian companies are examined vertically within the glamping production chain and horizontally across the supply value chain. The investigation unveils a notable discovery: the integration of wood within glamping yields considerable carbon sequestration, wherein the wood employed sequesters 36.83 metric tons of CO₂ per glamping unit. This surpasses the carbon emissions entailed throughout the entirety of the glamping life cycle, ranging from 9.97 to 11.72 metric tons of carbon. Remarkably, a single wood-incorporated glamping structure has the capacity to sequester approximately 25 metric tons of carbon within a span of 50 years. In summary, the investigation underscores the capacity of responsibly sourced timber to function as a carbon reservoir, proficiently counterbalancing emissions across the entirety of the construction life cycle. The findings underscore the importance of sustainably sourced wood in achieving carbon neutrality and provide valuable insights for promoting sustainable building practices. This methodology has broad applicability beyond glamping structures, holding potential for replication and scalability across various sectors and regions, thereby contributing to global efforts towards mitigating climate change and fostering positive environmental change. Full article

Tall timber buildings represent an emerging and highly promising sector due to their potential to yield significant environmental and economic advantages throughout their entire life cycles. Nonetheless, the existing body of literature lacks a comprehensive exploration of the primary architectural and structural design considerations for such sustainable towers. To address this gap and to enhance our understanding of emerging global trends, this study scrutinized data from 49 tall timber building case studies from around the world. The key findings revealed the following: (1) Europe stood out as the region boasting the highest number of tall timber buildings, with North America and Australia following behind; (2) residential applications were the most preferred function for tall timber buildings; (3) central cores were the predominant choice for core configuration; (4) prismatic forms were the most prevalent design preferences; (5) composite materials were notably widespread, with timber and concrete combinations being the most prominent; (6) structural systems primarily featured shear–frame systems, especially shear-walled frames. By unveiling these contemporary characteristics of tall timber buildings, this research is expected to provide valuable insights to architects, aiding and guiding them in the design and execution of future sustainable projects in this field. Full article