Search Results (49)

This study aimed to elucidate the genetic variation patterns of hybrid larch during generational transitions, providing a theoretical basis for targeted genetic improvement and advanced hybrid breeding of pulpwood. Seven hybrid larch families and their progeny from the Qingshan National Larch Elite Seed Base in Linkou County, Heilongjiang Province, were used as experimental materials. Growth traits, wood properties, and pulping performance of both generations were measured and analyzed, and pulp production capacity was calculated accordingly. Significant differences were observed between the F₁ and F₂ generations across all traits. The F₂ generation showed greater genetic stability, though it was more susceptible to environmental factors. The LK3 × LG2 family was identified as elite through principal component analysis (PCA) and membership function analysis. Further analysis of intergenerational data confirmed that the LK5 × LO78-3 family exhibited superior genetic stability across generations, making it an optimal parental source. This study establishes a genetic foundation for the targeted genetic improvement of larch pulpwood, with important implications for advanced hybrid breeding and elite family selection. Full article

Eucalyptus urophylla is a core tree species for short-rotation industrial timber plantations in South and Southwest China. However, the dynamic correlation rules of its growth traits during the full rotation period remain unclear, and the theoretical research on early selection is insufficient. In this study, 12 pure E. urophylla clones (including U6 and MLA as controls) were used as plant materials. Based on the data of tree height (H), diameter at breast height (DBH, D), and individual tree volume (V) from 0.5 to 7.5 years old, the correlation rules of early and late growth traits were explored, core predictive traits were screened, and the optimal selection age was determined through rank correlation, phenotypic and genetic correlation analyses, combined with regression modeling and selection efficiency calculation. Early selection of E. urophylla clones was feasible: after 3.5 years, the early–late phenotypic and genetic correlation coefficients of H, D, and V all reached significant or highly significant levels, and the genetic correlation coefficients were greater than the phenotypic ones, indicating that genetic factors dominated trait correlations with little environmental interference. All five established early selection regression models passed the highly significant test. Among them, the models of D-early versus D-late, V-early versus V-late, and D-early versus V-late had the highest coefficients of determination (0.9293–0.9385), making them the optimal selection traits; the models of H-early versus H-late and H-early versus V-late had lower coefficients of determination (0.8010–0.8364) due to errors in height measurement. The best selection effect was achieved within 1/2–2/3 of the rotation period: for a 6-year rotation period (pulpwood), the optimal selection age was 3.5 years old (annual efficiency 1.318); for an 8-year rotation period (medium-diameter timber), it was 4.5 years old (annual efficiency 1.345); and for a 12-year rotation period (large-diameter timber), it was 6.5 years old (annual efficiency 1.379). This study not only fills the theoretical gap in early selection of E. urophylla during the full rotation period but also constructs an integrated early selection technology system of “trait screening—model prediction—age determination”. It provides key support for shortening the breeding cycle of E. urophylla and achieving precise control of breeding costs and offers important references for early selection research on fast-growing broad-leaved tree species worldwide. Full article

Soil organic carbon (SOC) is a critical component of the soil carbon pool, significantly influencing soil fertility and forest ecosystem productivity. Eucalyptus grandis (Rose Gum), one of the most widely introduced and economically valuable fast-growing tree species worldwide, plays an indispensable role in pulpwood production, construction, and bioenergy, and is commonly established and managed in successive rotations in operational practice. Despite its importance, the effects of successive planting on SOC and its labile fractions in plantation soils remain poorly understood. In May 2017, a space-for-time substitution approach was employed to study the effects of successive planting of E. grandis plantations on SOC and its labile fractions, including dissolved organic carbon, light-fraction organic carbon, particulate organic carbon, microbial biomass carbon, and readily oxidizable carbon. The results indicated that the content of SOC and labile organic carbon (LOC) fractions declined concomitant with an increase in successive planting generations. Specifically, total SOC content significantly decreased from 12.63 g·kg⁻¹ in the first-generation forest to 9.37 g·kg⁻¹ in the third-generation forest. The contents of LOC fractions also showed a significant decrease from the first to the second generation, but the rate of this decline slowed in the third generation. The soil carbon pool management index (CPMI) decreased significantly from 100 in the control forest to 46.64 in the third-generation plantation. Redundancy analysis identified water-soluble nitrogen and total nitrogen as the principal common factors exerting influence over SOC and its labile fractions in E. grandis plantations. These findings indicate that successive planting of E. grandis in artificial forests primarily reduces SOC and LOC fractions by lowering soil nutrient content, leading to a decline in soil carbon pool quality. The findings of this study may help provide a scientific basis for the sustainable development of E. grandis plantations in this region. Full article

Resin is a renewable non-timber forest product that is used as a raw material in a wide range of goods, thereby holding significant socioeconomic importance and relevance across multiple industrial sectors. This study aims to provide a comprehensive review of the main factors influencing natural resin production in Pinus stands, as well as to address the effects of these factors on tree growth dynamics and resin yield optimization. Among these factors, dendrometric characteristics, environmental conditions, and silvicultural practices, such as thinning, pruning, and prescribed burning, are particularly relevant. However, the scientific literature presents conflicting results regarding the influence of these factors on resin yield, as well as the impacts of resin tapping on tree growth and wood quality. These divergences highlight the complexity of the process and reinforce the need for further studies to clarify the interactions between silvicultural practices in Pinus stands and resin production. Understanding these practices is essential for the development and implementation of efficient silvicultural models aimed at optimizing resin tapping that are properly tailored to the specific conditions of each site. In this context, the development of management models that integrate both timber and resin production is fundamental for simulating management scenarios, generating yield forecasts, and supporting decision-making processes. It is worth noting that management models focused on maximizing resin production may differ from conventional approaches intended for pulpwood or sawtimber production. Nevertheless, integrating resin tapping with timber harvesting holds significant potential to increase the profitability of forest operations. Full article

Enhancing stress tolerance represents a critical objective in the genetic improvement of poplar trees. Populus × euramericana ‘Bofeng 3’ is a nationally certified elite poplar variety that was approved as a premium pulpwood variety for the southern area of Northeastern China. This variety grows quickly, has good yield, and resists frost; however, its weaker drought and salt tolerance limits its broader use in diverse environments. The aim of this study is to understand the genetic basis of the fast growth and stress-adaptation traits of this variety and to provide support for future molecular breeding efforts. We present a chromosome-scale genome assembly of Populus × euramericana ‘Bofeng 3’, totaling 445.53 Mb, of which with 90.39% is anchored to 19 chromosomes, containing 33,309 protein-coding genes and 45.36% repetitive elements. Comparative genomics showed that ‘Bofeng 3’ has expanded gene families related to photosynthesis and metabolism, and contracted families involved in stress responses, distinguishing it from other Populus species. Under drought (9137 leaf, 9403 root differentially expressed genes (DEGs)) and salt stress (2840 leaf, 3807 root DEGs), trend analysis revealed specific expression patterns. Several unique and expanded genes, including those for photosynthetic proteins, peroxidases, gamma-aminobutyric acid metabolism, and disease resistance, showed stress-responsive trends. Weighted gene co-expression network analysis identified five modules (three positive, two negative) that significantly correlated with photosynthetic traits, highlighting key candidates such as bZIP transcription factors and auxin/indole acetic acid genes. This study determined the genetic basis underlying the rapid growth traits of Populus × euramericana ‘Bofeng 3’, while providing genomic resources to establish a robust foundation for future gene editing and molecular breeding studies, including critical candidate genetic resources for developing superior drought- and salt-tolerant poplar varieties via targeted genome editing technologies. Full article

The Brazilian forestry sector comprises 9.94 million hectares of plantations, with eucalyptus dominating 75% of this area for pulp production. Technological advances have enhanced machinery performance, with the cut-to-length system being the primary method for pulpwood production. This study aimed to optimize the operational cycle of the log loader by evaluating productivity, operational cycles, and loading costs. Data were collected in Bahia, northeastern Brazil, from a forestry company operating under varying productivity scenarios and forest rotations. Time and motion studies were conducted to assess the log loader’s cycles, while productivity and cost analyses were performed. The results indicated that predictive models effectively explained productivity variations. The log loader’s productivity increased with the average volume per tree (AVT) and decreased with the number of movements, which consumed 68% of the cycle time due to wood adjustment and stack organization. Stages such as personal breaks, truck movements, crane adjustments, and cleaning of fallen material showed no significant statistical differences. Loading costs rose by up to 154% with increased movements and decreased with a higher AVT. Additionally, loading tri-train trucks significantly influenced transportation efficiency, emphasizing the importance of optimizing the log loader’s cycle to balance costs and enhance transportation operations. Full article

In the years 2022 to 2023, the harvesting of medium-sized round wood by the State Forests Service in Poland was estimated at between 22.2 and 23.6 million solid cubic meters per year. This is a significant amount of timber to be transported by road. It is a challenge for both transport companies and round wood buyers. The high variability of wood density depending on the species in combination with its moisture content is a significant issue in logistics operations. This study focuses on the influence of the absolute moisture content on selected parameters of wood deliveries, taking into account the differences in the seasons. The total weight of a transport set (GVW) and empty set (Tare) and the weight of the load (Net) were determined on the basis of weighing the transports on stationary scales at the recipient. The moisture content of each wood load was determined using the dryer-weigher method for sawdust taken from the cutting of several logs from the delivery. This study analyzed a total of 13,602 transports of ten tree species and two wood assortments of pulpwood (S2a) and industrial wood (S2ap) in four seasons in the years 2020–2022. Pine was the dominant species in 5352 deliveries, and spruce was the dominant species in 3161. In terms of seasons, 3983 transports were recorded in the summer, 3650 were recorded in the spring, and 3492 were recorded in the autumn. The lowest number of 2475 was in winter. The mean volume of delivered wood (from 13,602 transports) was 28.18 m³, with a range of results from 19.00 to 51.29 m³ and SD = 2.40. The mean weight of the shipment was 24.95 Mg, with SD = 3.36. The range was from 13.92 Mg to 38.20 Mg. The mean absolute moisture content (AMC) of all wood loads (regardless of species and quality) was 42.91%. The results varied significantly (SD = 6.41). The minimum value was 15.64%, and the maximum value was 66.79%. The absolute moisture content of round wood is related to the season, species and assortment of transported wood. Loads of hardwood have lower average solid cubic meter values than softwood. Full article

Approximately 12% of China’s papermaking raw materials are derived from wood, while the majority are sourced from branches. Styrax tonkinensis is a more desirable species for pulpwood in subtropical ultra-short rotations, whose branches are prone to breakage. Lignin has a significant impact on wood quality and pulping yield, and the growth process influences lignin biosynthesis. To explore the lignin biosynthesis pathway in S. tonkinensis, we determined the lignin content in the current-year and biennial branches on 20 July, 20 September, and 20 October and analyzed the transcriptome sequencing results. It was concluded that the lignin content showed an increasing trend in the current-year branches (182.26, 206.17, and 213.47 mg/g, respectively), while that in the biennial branches showed a decrease in the samples taken in October, without significant difference (221.77, 264.43, and 261.83 mg/g, respectively). The transcriptome sequencing results showed that 91,513 unigenes were spliced with a total length of 92,961,618 bp. KEGG pathway analysis indicated that the upregulated DEGs were mainly enriched in the phenylpropanoid biosynthesis pathway. Our study suggested that CCoAOMT, COMT, peroxidase, and F5H may serve as key enzymes regulating lignin synthesis in branches of S. tonkinensis, thereby influencing the lignin content. Full article

Previous research has primarily focused on soil erosion issues in arid and semi-arid regions, with a limited understanding of soil erosion mechanisms in tropical areas. Additionally, there is a lack of a holistic perspective to determine the spatial attribution of soil erosion. The conversion of tropical rainforests into economically driven plantations, like rubber and pulpwood, has resulted in distinct soil erosion characteristics in specific regions. To enhance our knowledge of soil erosion patterns and mechanisms in tropical regions, it is necessary to examine soil erosion in the three major watersheds of Hainan Island from 1991 to 2021, which encompass significant geographical features such as tropical island water sources and tropical rainforest national parks. The study employed the China Soil Loss Equation (CSLE) model, slope trend analysis, Pearson correlation analysis, land-use transfer matrix, and spatial attribution analysis to examine soil erosion under different scenarios. The research results indicate that scenarios driven by the combination of natural and human factors have the greatest impact on soil erosion changes in the entire study area. Co-driven increases affected 53.56% of the area, while co-driven decreases affected 21.74%. The 31-year soil erosion showed an overall increasing trend. Human factors were identified as the primary drivers of increased soil erosion in the Nandu River basin, while a combination of climate and anthropogenic factors influenced the decrease in soil erosion. In the Changhua River basin, climate and human activities contributed to the soil erosion increase, while human activities primarily caused the decrease in soil erosion. In the Wanquan River basin, climate intensified soil erosion, whereas human activities mitigated it. This study underscores the significant combined impact of human activities and natural factors on soil erosion in tropical regions. It emphasizes the importance of considering human-induced factors when implementing soil erosion control measures in tropical regions. Full article

The aim of the study was to test the applicability of forecasting in the analysis of the variability of prices and supply of wood in Poland. It relies on the autoregressive integrated model (ARIMA) that takes into account the level of cyclic, seasonal, and irregular fluctuations and the long-term trend as tools for the assessment of the predictions of the prices of selected medium-sized wood assortments. Elements of the time series were determined taking into account the cyclical character of the quarterly distribution. The data included quarterly information about the supply (amount) and prices (value) of wood sold by state forests in the years 2018–2022. The analysis was conducted for the most popular assortments: logging slash (M2, M2ZE), firewood S4, and medium-sized wood S2AP. In the period studied (years 2018–2022), the average rate of price variation was widely scattered. The average rate of price variation for the M2ZE assortment amounted to 7%. The average rate for M2 assortment was 1%, while the medium-sized S2AP assortment displayed the greatest variation of 99%. This means that between 2018 and the present, the price increased by nearly 100%. No major fluctuations were observed for the S4 assortment and its average rate of variation amounted to 0%. The analysis found seasonal variation was observed only for S4 firewood, the price of which went up each year in October, November, and December. For this reason, the forecast was made with the seasonal autoregressive integrated moving average (SARIMA) version of the model. It is difficult to forecast the price of wood due to variations in the market and the impact of global factors related to fluctuations in supply. Full article

Longleaf pine once covered 37 million hectares in the southern United States. However, it currently occupies only 5% of the original area. Efforts have been ongoing for the last decade to restore longleaf pine. The expected expansion in the area under longleaf pine has raised concern among wood-consuming mills regarding a potential increase in the total wood procurement cost, as wood availability per unit of land is typically lower for longleaf than for loblolly and slash pines for the first few decades. Therefore, a simulation model was developed in this study, examining the impact of the gradual adoption of longleaf pine by landowners on the total wood procurement cost of a pulp mill located in South Georgia over a 40-year simulation period. Results show no statistically significant difference between scenarios for maximum distance, total cost, and total distance over the simulation period. Our study will guide stakeholder groups to balance the needs for longleaf pine restoration and the reduced cost of wood procurement for wood-consuming mills. Full article

Climate change is an important issue that increasingly affects our lives. One of the proposals for mitigating climate change is fighting biodiversity loss, which can support climate mitigation and adaptation actions. In Poland, the possibility of excluding large tracts of forest areas from use is being considered. The discussed the exclusion of forest land from use will affect the timber supply and market, especially for broadleaved wood. The main purpose of this analysis is to present a timber supply forecast, with a particular focus on the possibility of obtaining broadleaved hardwood timber in Poland from forests managed by State Forests National Forest Holding under three scenarios that assume different criteria for selecting forest areas for protection. The work was divided into two main phases: (1) the analysis of historical sales volume of wood products and average sale prices of hardwood during the period 2011–2020; (2) the preparation of a forecast of the potential possibility of maintaining broadleaved hardwood production in the three decades between 2020 and 2049. In the forecast, it was assumed that about 2.7 million hectares of planted and production forests are excluded from use in order to implement the provisions of the 2030 Biodiversity Strategy. In Scenario “I”, the supply of merchantable broadleaved roundwood volume will be reduced to 14%–18% that of Scenario “0”. In Scenario “II”, 55% of the “0” scenario is harvested, and in Scenario “III”, 33%–37% of the “0” scenario merchantable broadleaved roundwood is harvested. The introduction of restrictions on timber harvesting as a result of Poland’s compliance with European Union requirements in the area of environmental protection will lead to a significant reduction in the supply of timber on the market. This may lead to a further increase in timber prices and an increase in the importance of large timber buyers at the expense of local buyers. The recommendations contained in the policy objectives that the EU sets for the states should be supported by a thorough analysis when selecting areas for strict protection. Full article

As the world’s population rises, there is a greater need for additional pulpwood for paper production worldwide. Therefore, this research aimed to evaluate the pulp and papermaking characteristics of Melia azedarach. Proximate chemical analysis, fiber morphology, pulping, bleaching, and physical tests were carried out to check the suitability of raw material. The proximate chemical analysis results showed that M. azedarach has a holocellulose content of 72.95% and a lignin content of 22.14%. Fiber morphology assessment revealed that the fibers were 0.571 mm long, 13.45 μm wide, and had a 2.52 μm cell wall thickness. Kraft pulping of M. azedarach was performed at different active alkali contents (5%, 10%, 15%, 20%, and 25%) and temperatures (150 °C, 160 °C, 170 °C, 180 °C, and 190 °C), keeping the sulfidity constant at 25%. The maximum pulp yield was 41.81% at an active alkali content of 15%, a temperature of 170 °C, and a cooking time of 90 min. The effect of pulping on the fiber morphology was studied using scanning electron microscopy, which showed that the fiber’s surface before pulping was tight and arranged in an orderly way, with a relatively complex texture. After pulping, lignin, hemicellulose, and cellulose were removed, and the fiber became softer and more loosened, containing micropores. The pulp produced was bleached, and sheet preparation and testing were performed. The prepared paper sheets had a tensile index of 23.3 Nm/g, a burst index of 1.4 kPa m²/g, and a tear index of 4.0 mN m²/g. This study concluded that M. azedarach could be a raw material for the pulp and papermaking industries. The results indicated that M. azedarach is also a potential alternative resource for pulp and paper production in Ethiopia. Full article

The Authors conducted a long-term follow-up study of a John Deere 1490 forwarder-mounted bundler owned by a Portuguese company and used for bundling logging residues from fast-growing eucalypt plantations located in Portugal and Spain. The study spanned 7 years, from 2011 to 2016. During this time, the machine clocked over 11,500 h and produced more than 200,000 bundles or 75,000 green tons of biomass. Bundle length was commonly 2.4 m, and bundle mass averaged 350 kg. Overall, the database contained 1752 daily records. Bundling productivity averaged 19 bundles per productive machine hour (meter hour, excluding all major delays). Mechanical availability was very high and averaged 93%. Utilization commonly ranged between 65% and 75%. Use and productivity showed a predictable seasonal trend and a slight decline over time. The latter might be due to wear, but also due to the increasingly challenging conditions faced by the company as the average worksite size sharply decreased from 2011 onwards. While almost extinct elsewhere, bundling seems to thrive in the Iberian plantations, possibly due to the industrial character of both eucalypt farming and bioenergy generation in the region. That allows the reaping of all integration benefits offered by bundling, while the cost of setting up a parallel biomass chain is minimized. Furthermore, bundling seems the ideal technique for efficient residue recovery where slash yields are low and roadside storage space is limited: these are the typical constraints of industrial eucalypt plantations, where planted area is maximized (=little landing space) and the largest possible proportion of the tree mass is turned into pulpwood (=relatively low residue yield). Full article

Despite positive signals from increasing growing stock volumes and improved roundwood trade, first commercial thinnings (FCTs) tend to be a bottleneck in Finnish forest management and forestry. The reasons are many, but probably the most crucial would be the lack of simultaneous economic incentives for participating agents, i.e., private forest owners and forest machine contractors. This is due to poor stand characteristics in most FCT cases: low cutting removal with small average stem size. There are five predetermined management options: (1) Industrial wood thinning with only two timber assortments, pulpwood and saw logs, (2) Integrated procurement of industrial and energy wood, (3) Energy wood thinning solely consisting of delimbed stems, (4) Whole-tree energy wood thinning with an energy price of 3 € m⁻³ and (5) Whole-tree energy wood thinning with energy price of 8 € m⁻³, that were applied for six separate forest stands located in Northern Finland, and derived from a database representing stands with an urgent need for FCT. Then, a two-phase financial analysis consisting of stand-level optimization (private forest owners) and profitability assessment (contractor) was conducted in order to find out whether there would be simultaneous economic incentives for both participants of FCT. The stand-level optimization revealed the financially best management options for a private forest owner, and then, for a contractor, the profitability assessment exposed the profit (or loss) associated with the particular management option. In brief, our results demonstrated that conducting either an industrial wood thinning (1) or an integrated procurement (2) resulted in a positive economic incentive for both the private forest owner and the contractor in all six cases (stands). Further, applying energy wood thinning with delimbed stems (3) would even generate a financial loss for the contractor, given the roadside prices applied in this study. Full article