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The results of a quantitative assessment of carbon pools and fluxes and their changes in the first year after clearcutting in the middle-taiga mixed coniferous–small-leaved forest of the Komi Republic are presented. The carbon stock in the initial forest was up to 14.7 kg C/m2 with the main carbon pools in the stand (62.4%), soil (35.5%), biomass of ground cover (1.1%), and coarse woody debris (1.0%). During logging, 6.6 kg C/m2 was removed as part of the stem wood (44.8% of the ecosystem carbon stock or 71.8% of the stand phytomass carbon). In the first year after logging, the ecosystem carbon stock decreased to 8.1 kg C/m2, including 7.1% in the forest vegetation and 66.8% (5.4 kg C/m2) in the soil. The proportion of coarse woody debris increased significantly in the felled area to 1.9 kg C/m2 (23.4% the ecosystem carbon stock) due to the appearance of logging residues, which in the future should contribute to the emission of carbon dioxide into the atmosphere from the felled area. As a result of clearcutting, the input of tree litterfall onto the soil surface reduced by 42 times. An insignificant (≈10%) increase in the carbon dioxide emissions from the soil surface was detected in the felled area. Logging leads to a decrease in the removal of carbon from the forest litter into lysimetric waters. The data obtained will find application in assessing the impact of clearcutting on the carbon cycle in taiga ecosystems. [ABSTRACT FROM AUTHOR]

Ips cembrae, an important pest of European larch (Larix decidua), has caused local outbreaks in the last two decades and is becoming increasingly important as the proportion of European larch in forests increases.In 2021–2023, larch logs and piles of branches were placed into shaded forest and sunlit areas every month to study bark beetle species on logging residues. After adult emergence, the logs and branches were debarked, and the infestation density of bark beetles was analysed. The results indicate that shading, log diameter and top/bottom parts of log had a significant effect on infestation density of I. cembrae on logs. The infestation density of I. cembrae was higher on logs felled between December and June than on logs felled between July and November.Shading of branches was the most significant variable affecting the bark beetle species composition on branches. All four of the bark beetle species recorded were affected by diameter of the branches. Ips cembrae primarily infested sunlit branches while Cryphalus intermedius preferred shaded branches. In contrast, the infestation densities of Pityogenes chalcographus and Pityophthorus pityographus seemed to be affected primarily by moisture content of the branches. [ABSTRACT FROM AUTHOR]

Aims: Tree logging in tropical tree plantations results in significant soil disturbances that negatively impact soil biodiversity and soil functioning. Here, we aimed to assess the effects of adding organic matter (OM) to soil after rubber tree logging on soil functioning over time. Methods: The experiment was conducted in two contrasting soil types in Ivory Coast. Four practices were replicated, including a control with no residues, the presence of legumes only, legumes and all tree parts excluding the trunk, and legumes and all the parts of the tree including the trunk. We monitored the response of soil nematode communities every six months for 24 months in each practice. Samples were collected from the topsoil layer (0–10 cm) in the interrow, and we also monitored soil carbon transformation by measuring in situ basal soil respiration, labile soil carbon and organic matter decay using the bait lamina method. Results: The results showed a sharp decrease in nematode abundance after tree logging, but OM restoration increased nematode abundance, the relative abundance of bacterivores, and resource availability to the soil food web. The resilience of the nematode communities depended on soil conditions and the amount and quality of logging residues. Total nematode abundance was positively and significantly related to soil functioning, measured through basal soil respiration, labile soil carbon, and organic matter decay rate. Conclusion: The results suggest that restoring logging residues can be an effective way to restore soil biodiversity and mitigate the negative impact of clear-cutting in tropical rubber plantations. [ABSTRACT FROM AUTHOR]

Wildfire pressure involves today to implement silvicultural practices that provide a good compromise between reducing fire risk and maintaining ecological functioning. Thinning reduces tree density and low branches, but results in the deposition of a considerable biomass of woody debris on the ground (up to 4800 g m2 in this study). They can be eliminated by prescribed burning, but this raises questions about the fire intensity that can be generated and the impact on soil fauna. We undertook the monitoring of a thinning and prescribed burning operation, separated and combined, in November 2020, in a Pinus laricio stand prone to fire risk, located in Bavella, Corsica. Fuel load was determined, and temperature measurements in the soil were performed using K‐type thermocouples. Soil arthropod populations were monitored using pitfall traps, in particular Collembola, Acari, Aranae, and Coleoptera. The combination of thinning and burning resulted in a fire intensity of 75.8 versus 8.4 kW m−1 for burning alone. Maximum temperature rise measured at −2 cm below the surface was less than 5°C for both treatments. The combination of thinning and burning did not result in higher fire intensity at ground level than burning alone, and the soil showed high insulation capacity. Most of the woody debris that burned was small‐diameter, and large‐diameter debris remained unconsumed. This burning, performed during a period of low biological activity, had no effect on soil arthropods, and the presence of large debris may have provided refuge areas. Collembola group was the faster to recover, and were followed by cohorts of predators in summer, especially Acari. Our results suggest that a combination of burning and thinning in autumn may be beneficial for fire prevention. However, the decomposition of woody debris in relation to fire risk, and the occurrence of pests after these treatments need to be monitored. [ABSTRACT FROM AUTHOR]

European beech (Fagus sylvatica L.) forests in Central and Southern Italy are managed applying the shelterwood system. Prior to the regeneration cut, it is common to apply 2–3 thinning interventions, aiming to obtain mostly firewood, considering the low dimension and poor quality of the stems. These interventions are usually carried out by local forest enterprises relying on a low or medium level of mechanization (small‐scale forestry). In particular, the short wood system is applied, thus processing the logs to 1 m length and extracting them with forestry‐fitted farm tractors equipped with forwarding bins. Despite the large application of this harvesting system in the Mediterranean forestry, no information is available in the literature about its possible disturbance to the forest soil. To fulfill this knowledge gap, we developed the first assessment of soil physicochemical (bulk density, penetration resistance, shear resistance, organic matter content) and biological (soil microarthropods biodiversity evaluated with the QBS‐ar index, that is, an index based on the idea that high‐quality soils have more groups of microarthropods that are morphologically better adapted to the soil than low‐quality soils) properties for this kind of logging operation. In three case study areas in Central Italy, we applied an experimental design to evaluate separately the impacts related to the passage of the machine and that of the silvicultural treatment itself. We further applied linear mixed‐effect models to investigate the relationship between changes in soil physicochemical and biological properties. We found the effect of the silvicultural treatment to be negligible, but there was a significant alteration of the investigated parameters in the soil affected by the passage of the machine. Soil penetration and shear resistance doubled in the forwarding trails (0.25 MPa and 4.02 t m−2, respectively) in comparison with the other two experimental treatments (control area and soil not affected by the machine passage; about 0.12 MPa and 2.10 t m−2, respectively). Soil organic matter and soil microarthropod biodiversity (QBS‐ar index) were reduced by 25% in the forwarding trails (about 30% and 92 respectively) in comparison with the soil not affected by the machine passage (about 39% and about 130, respectively). Such significant disturbance, which occurred even if the applied machinery had lower weight in comparison to other alternatives (forwarders), is related to the high number of machine passes needed to extract the woody material with forwarding bins applying the short wood system. We found a significant relationship between soil compaction and soil organic matter removal and microarthropod biodiversity, with the latter which resulted significantly lower in more compacted and organic matter‐poor soils. We demonstrated that this small‐scale extraction system can have a negative effect on soil features in the short term. We therefore recommend the application of best management practices, for instance placing brush mats and logging residues, on the forwarding trails to limit the soil disturbance within the framework of small‐scale forestry. We further recommend a wider application of aerial harvesting systems, which generally have lower impacts to the soil. However, this could happen only after an extensive training program aimed to increase the knowledge and skills of local loggers about aerial harvesting systems. [ABSTRACT FROM AUTHOR]

In 2023, branches of European beech (Fagus sylvatica L.) were placed on 24 different study sites within beech stands in the Czech Republic to study the distribution of the beech bark beetle (Taphrorychus bicolor Her.). After infestation, the branches were placed in emergence traps to capture adults of the offspring generation. In total, 2167 adults of T. bicolor were captured across the 24 study sites. The average capture (mean ± SE) was 90.3 ± 24.4 adults per site. Statistical analyses, including GLMM and GLM, were employed to assess the influence of elevation and stand age on the abundance of T. bicolor. The results indicate that the distribution of T. bicolor is mainly influenced by the elevation and age of the beech stand. The number of captured adults decreased with elevation and increased with stand age. Climatic region, volumes of beech, and volumes of felled beech wood from principal felling and thinning felling had no significant effect on the number of T. bicolor adults captured. We found that, overall, 73.37% of Czech beech stands (at elevations 300–650 m a.s.l.) are possibly threatened (either highly or slightly) by the large occurrence of T. bicolor, because they are present at elevations where T. bicolor is widespread. No outbreaks of T. bicolor have yet been reported in the Czech Republic, but with the increasing amount of beech planted, combined with global climate change, the possibility of outbreaks in the future cannot be excluded. [ABSTRACT FROM AUTHOR]

Torrefaction and combustion have been applied to naturally decomposed red oak logging residues. The results indicated that four-year natural decomposition would lower the energy density of red oak from 20.14 to 18.85 MJ/kg. Torrefaction reduced the O/C and H/C ratios but improved the energy yield values. Two combustion stages were observed for all samples, and no hemicellulose derivative thermogravimetric peak appeared for torrefied samples. The differential scanning calorimetry exothermic heat flow increased after torrefaction. In addition, the Kissinger–Akahira–Sunose average activation energy of untorrefied samples decreased in the first stage (from 157.77 to 149.52 KJ/mol), while it increased in the second stage (from 131.32 to 181.83 KJ/mol). The ∆H, ∆G, and ∆S values of all samples decreased in the first stage, while they increased when the conversion rate was greater than 0.5 for torrefied samples. These findings can aid in a better understanding of the fuel performance of torrefied and untorrefied naturally decomposed red oak logging residues. [ABSTRACT FROM AUTHOR]

This article explores the use of logging residues in forestry to reduce the risk of fires, prepare areas for planting new trees, and use them as a valuable resource for the production of wood biofuels. While traditional methods of logging residue disposal include incineration in piles or swaths, this study examines an alternative approach known as the continuous slash-and-burn method. This method, although limited to firehazardous periods due to the use of paraffin, has such advantages as minimal thermal damage to the soil and accelerated decomposition of felling residues. The residues are charred rather than burned completely, increasing soil fertilisation and reducing fire hazard. This feature makes them less attractive to insect pests. Modern logging companies increasingly prefer efficient logging equipment instead of gasoline saws since the former improves the management of logging residues. Manual collection of residues on large stumps allows for forming larger piles. However, this method creates problems when transporting them to processing centers, for example, to upper storage sites. Therefore, the development of innovative transportation methods is a promising direction for further research. Thus, logging residues is a raw material, which is primarily valuable for the production of wood biofuels. Energy efficiency in the collection, processing, and transportation of these residues is crucial for their practical use. The consumed energy should be lower than the energy content of the residues, ensuring the feasibility of converting them into wood biofuels. [ABSTRACT FROM AUTHOR]

A significant amount of logging residue is produced during roundwood harvesting. Logs are often left in forest sites due to, for example, ecological or logistical aspects. Taking into account the fact that the number of studies focused on changes in the properties of the residue is very low, it was decided to conduct research on the effect of a three-year storage period in forest stands on the chemical properties and energy potential of the wood. The research design allowed for the determination of changes during up to three years of storage. The performed analysis showed a highly negative impact on the characteristics of the material. These adverse effects were probably caused by the activity of microorganisms such as fungi and bacteria, as evidenced by the increased concentrations of ergosterol and low-molecular-weight organic acids. Moreover, it was found that wood stored for three years was characterized by a lower cellulose content; an increased percentage of lignin; a reduced content of sterols (desmosterol, stigmasterol, lanosterol and β-sitosterol) and phenolic acids; and reduced antioxidant activity, as determined with the ABTS+ method. Storing logs also led to a reduction in the energy potential of the residues, as shown by a reduction in net and gross calorific value and an increased ash content. [ABSTRACT FROM AUTHOR]

Forest biomass is expected to remain a key part of the national energy portfolio mix, yet residual forest biomass is currently underused. This study aimed to estimate the potential availability of waste woody biomass in the Aizu region and its energy potential for local bioelectricity generation as a sustainable strategy. The results showed that the available quantity of forest residual biomass for energy production was 191,065 tons, with an average of 1.385 t/ha in 2018, of which 72% (146,976 tons) was from logging residue for commercial purposes, and 28% (44,089 tons) was from thinning operations for forest management purposes. Forests within the biomass–collection radius of a local woody power plant can provide 45,925 tons of residual biomass, supplying bioelectricity at 1.6 times the plant's capacity, which could avoid the amount of 65,246 tons of CO2 emission per year by replacing coal-fired power generation. The results highlight the bioelectricity potential and carbon-neutral capacity of residual biomass. This encourages government initiatives or policy inclinations to sustainably boost the production of bioenergy derived from residual biomass. [ABSTRACT FROM AUTHOR]

Wood chipboard, common in interior spaces for applications ranging from furniture to decorative panelling, often falls short due to the presence of toxic adhesives, posing risks to both human health and the environment. This research delves into the potential transformation of wood chipboard into a 100% bio-based product. Previous research has shown the possibility of the partial replacement of petrochemical-based adhesives with bio-based adhesives. Hence, previous results do not reach the policy ambitions of the Green Deal of making the Green Transition to a bio-based economy. For chipboard production, logging residues from Latvian State Forests were systematically gathered within two months post-logging, comprising primarily Picea abies and Pinus sylvestris biomass, including branches, needles, bark, and various particles. A custom chipper and Vibrotehnik PM-120 hammer mill were employed for particle size separation into three fractions via sieving: <2.8 mm, 2.8–8 mm, and 8.0–10.0 mm, and combined with binders and hot-pressed into board samples. As a result, particle boards containing 100% bio-based carbon were achieved, demonstrating the possibility of excluding petroleum adhesives from chipboard production, paving the way for new research exploring bio-based binders and conifer bark. [ABSTRACT FROM AUTHOR]

Climate change adaptation and mitigation strategies (CCAMS) are changes to the management of production forests motivated by the need to mitigate climate change, or adapt production forests to climate change risks. Sweden is employing CCAMS with unclear implications for biodiversity and forest ecosystem services (ES). Here, we synthesized evidence from 51 published scientific reviews, to evaluate the potential implications for biodiversity and a range of provisioning, regulating, and cultural ES, from the adoption of CCAMS relative to standard forestry practice. The CCAMS assessed were the adoption of (i) mixed-species stands, (ii) continuous cover forestry, (iii) altered rotation lengths, (iv) conversion to introduced tree species, (v) logging residue extraction, (vi) stand fertilization, and (vii) altered ditching/draining practices. We highlight the complexity of biodiversity and ES outcomes, identify knowledge gaps, and emphasize the importance of evidence-based decision making and landscape-scale planning when navigating choices involving the widespread adoption of CCAMS. [ABSTRACT FROM AUTHOR]

Research indicates that integrated systems, in which roundwood and energy chips are produced simultaneously, produce energy chips at the lowest cost. However, integrated systems may be feasible on a narrow range of sites. Post-harvest chipping, in which roundwood is harvested by one logging crew and energy chipping conducted independently by a second crew, may allow chips to be produced from more harvest sites. The goal of this study was to evaluate the feasibility of recovering logging residues and non-merchantable stems using post-harvest systems. Time-and-motion studies were conducted on both roundwood harvesting and post-harvest chipping on three harvest tracts on the Savannah River Site in the Coastal Plain of South Carolina. Hourly machine costs were estimated using the machine rate method. Harvesting costs per tonne were calculated using a modified Auburn Harvesting Analyzer. Energy chips were produced at an average estimated cost of $22.04 green t−1 (USD, onboard truck) and $31.96 t−1 delivered. Requiring the feller-buncher to fell and bunch non-merchantable stems reduced feller-buncher productivity by an average of 42% but did not reduce system productivity. This study suggests that post-harvest energy chipping can be a cost-effective alternative. [ABSTRACT FROM AUTHOR]

Wood pellets are a versatile ingredient to produce bioenergy and bioproducts. Wood pellet manufacturing in Canada started as a way of using the excess sawdust from sawmilling operations. With the recent dwindling availability of sawdust and the growth in demand for wood pellets, the industry uses more non-sawdust woody biomass as feedstock. In this study, woody biomass materials received from nine wood pellet plants in British Columbia (BC) and Alberta were analyzed for their properties, especially those used for fractionating feedstock to make pellets. Half of the feedstock received at the plants was non-sawdust. Moisture contents varied from 10 to 60% wet basis, with the hog having an average of 50%. Ash contents ranged from 0.3 to 4% dry basis and were highest in the hog fraction. Bulk density varied from 50 to 450 kg/m3, with shavings having the lowest bulk density. Particle density ranged from 359 kg/m3 for infeed mix to 513 kg/m3 for sawdust. In total, 25% of particles received were larger than 25 mm. The extraneous materials (sand, dirt) in the infeed materials ranged from 0.03% to 1.2%, except for one hog sample (8.2%). Plant operators use mechanical fractionation and blending to meet the required ash content. In conclusion, further instrumental techniques to aid in fractionation should be developed. [ABSTRACT FROM AUTHOR]

Blackwater occurs every winter in reservoirs with Eucalyptus plantations. The complexation reaction between ferric iron (Fe3+) and Eucalyptus leachate tannic acid from logging residues (especially leaves) is the vital cause of water blackness. However, the effect of Eucalyptus leaf leaching on the dynamic of iron in sediments and its contribution to reservoir blackwater remain unclear. In this study, two experiments were conducted to simulate the early decomposition processes of exotic Eucalyptus and native Pinus massoniana leaves in water (LW) and water-sediment (LWS) systems. In LW, high concentrations of tannic acid (>45.25 mg/L) rapidly leached from the Eucalyptus leaves to the water column, exceeding those of Pinus massoniana leaves (<1.80 mg/L). The chrominance increased from 5~10 to 80~140, and the water body finally appeared brown instead of black after the leaching of Eucalyptus leaves. The chrominance positively correlated with tannic acid concentrations (R=0.970, p<0.01), indicating that tannic acid was vital for the water column's brown color. Different in LWS, blackwater initially emerged near the sediment-water interface (SWI) and extended upward to the entire water column as Eucalyptus leaves leached. Dissolved oxygen (DO) and transmission values in the overlying water declined simultaneously (R>0.77, p<0.05) and were finally below 2.29 mg/L and 10%, respectively. During the leaching of Eucalyptus leaves, the DGT-labile Fe2+ in sediments migrated from deep to surface layers, and the diffusive fluxes of Fe2+ at the SWI increased from 12.42~19.93 to 18.98~26.28 mg/(m2·day), suggesting that sediment released abundant Fe3+ into the aerobic overlying water. Fe3+ was exposed to high concentrations of tannic acid at the SWI and immediately generated the black Fe-tannic acid complex. The results indicated that the supplement of dissolved Fe3+ from sediments is a critical factor for the periodic blackwater in the reservoirs with Eucalyptus plantations. Reducing the cultivation of Eucalyptus in the reservoir catchment is one of the effective ways to alleviate the reservoir blackwater. [ABSTRACT FROM AUTHOR]

The reduction of greenhouse gas (GHG) emissions demands a significant increase in the use of wood as a renewable energy source. However, environmental restrictions determine limits on the further growth of harvesting volume. Therefore, a viable solution to enhance the share of energy wood in Estonia's energy balance involves focusing on less exploited assortments of raw material and implementing precise logistics planning. In recent years, mild winters have posed challenges to the extraction of residues and local transport of wood fuels, taking place on soft and unfrozen soils. In such conditions, ensuring a reliable supply of wood fuels becomes rather complicated. When piles of logging residues on unfrozen soils are inaccessible, there is a need to process older piles. The quality of wood chips from such piles is lower compared to the norm. To investigate the impact of extra long-term storage of residues in piles, a study was conducted at the Järvselja Training and Experimental Forest Centre. In 2010, sample piles were created in birch and spruce final felling areas. Over an eight-year period, samples were regularly taken from the piles to analyse the properties of woody biomass during storage. The study results indicate that the quality of fuel from covered piles changes slowly during the first two years of storage. Subsequently, the degradation speed equalizes in both uncovered and covered piles. Despite extensive degradation and loss of dry matter during long-term storage (approximately 29% for Norway spruce and 55% for silver birch after eight years), the quality of dry fuels still meets standard requirements and remains acceptable for boiler houses. [ABSTRACT FROM AUTHOR]

As a renewable fuel, logging residues, as well as other dendromass, are in high demand. On the other hand, they can serve as a natural fertilizer and stabilize biodiversity in forest ecosystems. Therefore, they need to be used rationally, with due care for the volumes extracted from a particular stand. The volume of logging residues is difficult to measure; thus, foresters need a tool to estimate it, ideally via a simple method based on easily measurable parameters. Conversion factors, based on tree stem volume can serve this purpose. In this study, we develop such conversion factors for thinnings of Norway spruce (Picea abies (L.) H. Karst.) stands. First, we analyzed the relationship between the tree stem volume (ranging between 0.03 and 0.44 m3 stem−1) and the volumes of related logging residues or wood chips via linear regression and correlation analysis. Then, we assessed the significance of differences between volumes of logging residues or wood chips for trees in the five relevant stem volume classes and determined appropriate conversion factors. The conversion factors for wood chips ranged between 1.37 loose cubic meters of logging residue per cubic meter of timber in the largest stem volume class to 2.17 for the smallest stem volume class. The model, on which the conversion factors were based had a coefficient of determination of 0.88. Conversion to logging residue volume yielded factors ranging from 2.2 stacked cubic meters per cubic meter of timber for the largest stem volume class to 10.2 in the smallest stem volume class. The coefficient of determination of the underlying model was 0.69. The conversion factors are based on sufficiently accurate models and can be used in practical forestry for planning purposes, recordkeeping, and remuneration of loggers. [ABSTRACT FROM AUTHOR]

Determining the nutrient stocks and revealing the extent to which these stocks will be affected by the interventions in forest ecosystems are crucial for sustainable forest management. This study aimed to determine the nutrient stock of cedar (Cedrus libani A. Rich.) plantations at different stands with various diameter classes and estimate the nutrient stock to be removed from the forest due to harvesting. Soil and plant samples were collected from 40 plots in Eskişehir and Afyonkarahisar provinces in Turkey. The variation in the nutrient concentrations and stocks of different components of the ecosystem were evaluated by analysis of variance and the decrease via harvesting by regression analysis. The results showed that the concentrations of N, P, K, Mg, S, Fe, Zn, and Mn were highest in the needles, Ca in the bark, Cu in the needles, dead branches, and root. In the large-diameter forest (LDF), dbh=20.0–35.9 cm, the highest P stock was found in the trees, Fe stock in the forest floor, and S stock in the soil and trees. As a result, the forest floor should be protected as it is the crucial component of both the nutrient cycle and the Fe stock in the ecosystem. In LDF, 28.4–37.3% of the nutrient stored in the trees would be removed from the ecosystem in the case of moderate thinning with whole-tree harvesting, while only 5.9–14.1% of the nutrient stock in the case of stem-only harvesting. For these reasons, leaving logging residues after harvesting in the forest would minimize nutrient loss. The study results showed that improved nutrient management in a forest ecosystem will make a significant contribution to the sustainability of forests. [ABSTRACT FROM AUTHOR]

The article "Carbon neutrality: A comprehensive bibliometric analysis" by Zhang et al. explores the trends in carbon neutrality publications from 2006 to 2021 using the Web of Science Core Collection databases. The authors identified a total of 989 documents related to carbon neutrality, with 86% of them published in specific databases. However, discrepancies in the data analysis and search strategy employed by the authors raise concerns about the accuracy and integrity of the findings presented in the original paper. It is emphasized that future research should utilize rigorous and appropriate search strategies to maintain the standards of scholarly contributions in the field. [Extracted from the article]

Biofuel is encouraged because of its low impact on climate change. A new framework was developed to accurately assess the climate change impacts (CCI) of biofuel by integrating the atmospheric carbon cycle model and vegetation carbon dynamic models. Forests with different growth rates (fast, medium, slow) and three collection intensities (71%, 52%, 32%) of logging residues were presumed to test the performance of this framework. The CCI of biofuel was analyzed under two functional units: 1 GJ of biofuels and 1 ha of forests to supply biofuels. According to this study, increasing the forest growth rate could decrease the CCI in both functional units. Increasing the collection intensity could decrease the CCI of 1 GJ of biofuel but increase the CCI of 1 ha of forest land (unless the impacts were negative in fast-growth forests with high and medium collection intensities). Producing bioethanol resulted in a lower CCI (−3.1–67.7 kg CO2 eq/GJ) compared to bio-diesel (29.3–94.7 kg CO2 eq/GJ). Hence, collecting all available logging residues (without inhibiting forest regrowth) to produce low CCI biofuels such as bioethanol was found to be the optimal option for achieving high mitigation effects. [ABSTRACT FROM AUTHOR]

This study assessed the safety measures and operational challenges of inland waterway transport along the Oron - Calabar route. Observation and structured questionnaires were used for the collection of data. Quantitative data was analyzed using descriptive statistics, while qualitative data was coded and analyzed using the 4-point Likert scale, which was converted to a relative importance index (R.I.I.) for each factor, posing a challenge to operators. The result showed that safety equipment was provided onboard boats by operators. The R.I.I. computed showed that boat and engine replacement (R.I.I. = 0.874) was the most challenging factor, while water hyacinth (R.I.I. = 0.418) was the least. Other challenges were frequent bad weather conditions, high running costs, floating logs and debris, extortion by law enforcement agents, difficulty making headway against the opposite current, high cost of safety equipment, passengers' refusal to adhere to safety measures, and poor berthing facilities in their order of impact. Proper funding and enforcement of safety measures are hereby recommended. [ABSTRACT FROM AUTHOR]

Interactions between vegetation and sediment in post‐fire landscapes play a critical role in sediment connectivity. Prior research has focused on the effects of vegetation removal from hillslopes, but little attention has been paid to the effects of coarse woody debris (CWD) added to the forest floor following fires. We investigate the impacts of CWD on hillslope sediment storage in post‐fire environments. First, we present a new conceptual model, identifying "active" storage scenarios where sediment is trapped upslope of fire‐produced debris such as logs, and additional "passive" storage scenarios including the reduced effectiveness of tree‐throw due to burnt roots and snapped stems. Second, we use tilt table experiments to test controls on sediment storage capacity. Physical modeling suggests storage varies nonlinearly with log orientation and hillslope gradient, and the maximum storage capacity of log barriers in systems with high sediment fluxes likely exceeds estimates that assume simple sediment pile geometries. Last, we calculate hillslope sediment storage capacity in a burned catchment in southwest Montana by combining high‐resolution topographic data and digitization of over 5000 downed logs from aerial imagery. We estimate that from 3500–14 000 m3 of sediment was potentially stored upslope of logs. These estimates assume that all downed logs store sediment, a process that is likely temporally dynamic as storage capacity evolves with CWD decay. Our results highlight the role that CWD plays in limiting rapid sediment movement in recently burned systems. Using a range of potential soil production rates (50–100 mm/ky), CWD would buffer the downslope transport of ~35–280 years of soil produced across the landscape, indicating that fire‐produced CWD may serve as an important source of sediment disconnectivity in catchments. These results suggest that disturbance events have previously unaccounted‐for mechanisms of increasing hillslope sediment storage that should be incorporated into models of sediment connectivity. [ABSTRACT FROM AUTHOR]

Increasing size, severity, and human proximity to fires in the western US are driving a need for more effective ecosystem restoration in the immediate post-fire period. Surface treatments, such as mastication of logging slash, reduce erosion and improve soil nutrient and water retention on steep slopes. However, few studies have investigated the impact of these treatments on arthropod communities over time. Our objective was to determine which insect communities return to these treated areas and if the mulch changes the community structure over time. We surveyed arthropod abundance using pitfall traps in mulch treatments in a landscape-scale fire near Flagstaff, Arizona, and a controlled split-plot experiment outside of the larger fire footprint. Predatory beetles were more abundant in mulch in the large landscape treatment, with no differences in abundance in the split plots. Fungivores had no significant mulch preference, and several native bark beetles were more abundant in the untreated sites. We found that the size of the fire footprint and distance to the intact forest matrix likely impact arthropod community composition over time. We were unable to fully evaluate vegetation recovery, but further work will allow us to understand how surface treatments impact the interaction of arthropods and vegetation. [ABSTRACT FROM AUTHOR]

Currently, fossil fuels are used to produce fuels and electricity, which are finite sources and have a negative impact on the natural environment. An excellent alternative to these fuels is biofuels, such as bioethanol from waste forest biomass. Pine needles are one of the most important available forest biomass materials with s significant impact on local understory vegetation. Forest waste biomass, which is a rich source of lignocellulose, can be used in various ways, such as for the eco-economical production of bioethanol. The aim of this study was to analyze the possibilities of bioethanol production from pine needle biomass obtained from forest land following different soil preparations and logging residue management. The pine needle dry matter yield, chemical components of pine needle biomass (cellulose, hemicellulose, lignin), and the amount of ethanol yield per hectare were evaluated. The highest average yield pine needle equal to 6.17 Mg∙ha−1 was observed. Bioethanol yield per hectare from this biomass was the highest for plowing with the LPZ-75 plow and was 1.08 m3∙ha−1. The discussed results were confirmed by detailed statistical analysis. To sum up, the researched pine needle biomass turned out to be an interesting raw material with the potential for bioethanol production. [ABSTRACT FROM AUTHOR]

Non-native bark beetle species represent a major threat to forest ecosystems. The bark beetle Ips amitinus has recently expanded its range from Finland into northern Sweden. In the present study, we asked the following questions: (i) What is the distribution status in Sweden? (ii) Is there a difference in preference and reproductive success between Norway spruce and Scots pine? (iii) How common is the species after range expansion and does it influence the native community of bark- and wood-boring beetle species? We established the presence of I. amitinus and co-existence with the native community through checks of logging residues at 382 localities in northern Sweden. In addition, attack densities and reproductive success were compared between spruce and pine through investigating field material and by a no-choice rearing experiment. We found that I. amitinus is distributed over large parts of northern Sweden. Within its distribution area, it was found in 58% of all checked localities. It is one of the most common bark beetle species in logging residues and a higher proportion of Norway spruce objects compared to Scots pine were colonised. Attack density and reproductive success were higher in Norway spruce in field material and in the rearing experiment. There was no significant difference in the number of native bark- and wood-boring beetle taxa between localities where I. amitinus was present or absent. [ABSTRACT FROM AUTHOR]

Intensive forestry is a threat to biodiversity, and therefore actions are made to mitigate this loss. The actions are, however, designed based on available knowledge about the requirements of species, and for saproxylic insects this concerns mainly Coleoptera, while the diverse but poorly known Hymenoptera has contributed less. In this paper we therefore asked whether the substrate requirements of Hymenoptera (divided as parasitoids and non-parasitoids) are similar to those of Coleoptera and Diptera. We used an insect material reared from logging residue wood for the comparison. Theoretically parasitoid Hymenoptera should be less specialised than Coleoptera and other host species as they belong to a higher trophic level. However, we found no such difference and even an opposite trend, that parasitoids were more specialised than beetles. Parasitoids had significantly more species in newly dead wood of fine diameter (1–4 cm, compared to coarse wood of 8–15 cm) compared to other groups. This is probably due to that many of them have bark beetles as hosts. The non-parasitoids were less specialised than the other groups and more confined to old wood (4–5 years), which is in line with that many of them are aculeate wasps building nests in emergence holes from other insects. Implications for insect conservation: The habitat requirements of Hymenoptera suggest that the conservation actions designed for the well known groups are also applicable for them. The parasitoids' association to trivial substrates (fine wood) suggest a good supply of breeding habitat, whereas their high specialisation in combination with higher trophic level suggest they contain an even higher proportion of threatened species than Coleoptera. How this is traded off needs further studies. [ABSTRACT FROM AUTHOR]

The title of the current Special Issue, "Feature Papers in Materials Simulation and Design", has identified the aims of this collection since its opening: the gathering of research works and comprehensive review papers that advance the understanding and prediction of material behavior at different scales, from atomistic to macroscopic, through innovative modeling and simulation. The paper by Chen et al. [[4]] aimed at studying the thermal properties and thermoelectric performance of imidazole-graphyne (ID-GY) by combining first principle calculations with the Boltzmann transport theory. The last paper by Cheng and Vescovini [[16]] presented instead an accurate and efficient numerical method for the analysis and design of Variable Stiffness (VS) laminates. Civalek et al. [[11]] developed an efficient eigenvalue algorithm for the axial vibration analysis of embedded short-fiber-reinforced micro-/nano-composite rods subjected to arbitrary boundary conditions. [Extracted from the article]

Forest slashing and burning is a key characteristic of shifting cultivation. Its intensification is a major anthropogenic cause of deforestation, as it reduces forest resilience. We analyzed the reforestation process in the regenerating shifting cultivation lands in India's Western Ghats, a megadiversity hotspot. An actinorhizal shrub, Elaeagnus conferta, was associated with the regenerating thickets' higher density and higher species diversity. Its presence increased the thicket density by >2.8‐fold and the species diversity by >2.5‐fold; these thickets showed >1.5‐fold higher Shannon's diversity index than those without it. Moreover, the thickets containing E. conferta showed >7‐fold more multi‐species seedlings. Liquid chromatography‐mass spectrometry analysis showed that rhizosphere soils of E. conferta containing thickets had >10‐fold higher gibberellic acid (GA3) concentrations than the E. conferta‐deplete thickets. When E. conferta was potted separately, its root nodules, roots, and rhizosphere soil showed about 3.6, 2.0, and 0.4 μg/g GA3, respectively. These E. conferta root and rhizosphere soil GA3 concentrations were >10‐fold higher than those shown by other co‐occurring species. These elevated GA3 levels were likely due to E. conferta's association with the rhizosymbiont Frankia elaeagni. Frankia elaeagni's GA3 synthesis may promote plant recruitment by stimulating seed germination and explain why we measured higher seedling density and plant diversity in E. conferta containing thickets. We hypothesize that E. conferta plays a two‐stage pioneering role in the reforestation process by providing GA3 to facilitate seed germination and providing nitrogen for the developing plantlets. We recommend the inclusion of E. conferta in Western Ghats' reforestation programs. [ABSTRACT FROM AUTHOR]

Short rotation poplar plantations grow on flat and even terrain, and the interrow spacing is wide enough for easy machine access. If the terrain is firm enough, one may consider moving the classic roadside chipping operation directly into the field (i.e., terrain chipping), thus saving on wood extraction cost. This study compared the efficiency and cost of roadside and terrain chipping conducted with exactly the same equipment, to assess the benefits offered by the versatile deployment of a standard chipping operation, whereby the operation can be moved inside the stand whenever terrain conditions are suitable. The study was conducted at 12 sample plots, containing about one truck load of chips each (i.e., approximately 11 bone-dry tons or BDT). Plots were arranged as alternate windrows on a 8.5 ha field. Data was collected for the whole supply chain, from field to factory. The factory was located 14 km from the field. Delivered cost was 53 € BDT-1 and 70 € BDT-1 for roadside and terrain chipping, respectively, i.e., terrain chipping was 1/3 more expensive than roadside chipping, even if the latter included the additional cost of forwarding the residues to the roadside. The chipper-truck used for the test could not cope with small scattered residue piles (32 BDT ha-1), and the cumbersome reposition maneuver became the main hurdle to efficient operation. Further improvements might be achieved by pre-bunching the residues, introducing a dedicated terrain chipper or bundling the residues and taking the bundles to the factory for centralized chipping. [ABSTRACT FROM AUTHOR]

Background: Salvage logging is commonly carried out after forest fires, and mastication of the logging slash is usually prescribed to reduce the risk of infestation by insect pests in NW Spain. Aims: To evaluate how post-fire masticated slash depth affected vegetation regeneration (cover, diversity and load) and soil variables (soil organic carbon and soil compaction). Methods: In October 2017, a fire that completely burned tree crowns and caused moderate soil burn severity was selected for study. At the end of 2017, the burned trees were logged and logging slash was masticated. Twenty plots were established in June 2020 in those areas to analyse the effect of the depth of masticated slash on soil compaction, vegetation recovery, fuel distribution and carbon accumulation. Key results: The depth of masticated slash did not affect soil compaction, total vegetation cover or species diversity. Mean pine seedling density was significantly higher areas where the masticated slash depth was lower. Fuel loads and soil carbon content did not vary with the depth of masticated slash. Conclusions: A lower masticated slash depth seems to be more favourable for pine regeneration. Implications: These results may be useful for managers to favour natural regeneration in similar pine stands after fire. This study aimed to evaluate how post-fire masticated slash depth affected vegetation regeneration to provide information for forest management planning. The masticated slash depth did not have significant effects on vegetation cover or species diversity 2.5 years after treatments. A lower slash depth favoured pine regeneration. [ABSTRACT FROM AUTHOR]

Key message: Removal of logging residue negatively affected tree diameter and height, but had no significant effect on the basal area of the subsequent stand (in the mid-term). On the other hand, different methods of mechanical site preparation (bedding, plowing furrows, and trenching) had no effect on tree growth 1 year after planting, but had a significant effect on tree diameter, tree height, and basal area in the mid-term. Bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands, even when planted on sandy, free-draining soils. Context: Increased use of logging residues in forests may address the growing demand for renewable energy. However, concerns have arisen regarding the depletion of the forest soil, resulting in a decrease in the productivity of the next forest generation. Identifying the drivers of forest growth may be the key to understanding the relationship between logging residue removal and stand productivity. Aims: Quantifying the effect of three mechanical site preparation methods (bedding, plowing furrows, and trenching) combined with five methods of logging residue management (complete removal, comminution, incineration, leaving whole, comminution with, and without mixing with topsoil) on growth of subsequent Scots pine stands, 1 year and 12 years after planting. Methods: The experiment was set up as a randomized complete block design of 45 plots with three replications of combinations of three mechanical site preparation methods and five logging residue treatment methods. Results: The effects of the different methods of mechanical site preparation were not significant 1 year after planting but bedding treatment caused increase in DBH, tree height, and basal area after 12 years. Various methods of logging residue management did not cause any differences in the survival rate nor the basal area of the next-generation stands; however, there was a significant influence on tree sizes. Moreover, the effects changed with time; in plots with a complete removal of logging residues, the trees were the highest 1 year after planting, but after 12 years, their height and DBH were the lowest. Conclusions: It can be concluded that bedding treatments could have a significant positive impact on the productivity of the subsequent Scots pine stands. No effect found of different logging residue treatments on the productivity of Scots pine stands further confirms that the increased removal of biomass from the forest environment does not necessarily result in its rapid degradation. Observations at longer term are however needed to obtain the full spectrum of responses to logging residue removal. [ABSTRACT FROM AUTHOR]

Techniques based on electrical resistance and near-infrared (NIR) spectroscopy were used to determine the moisture content (MC) of logging residues and sweet sorghum. The MC of biomass is a factor to be controlled that can affect the quality of final products. To accurately measure the moisture in fragmented materials, it is essential to increase the bulk density of the materials by compression. The low bulk density increased the error from the oven-drying MC and the variation between repeated measurements. The calculated correction factor made it possible to use a commercial wood moisture meter for biomass materials. Ordinary least squares regression models built with the electrical resistance data achieved coefficients of determination (R²) of 0.933 and 0.833 with root mean square errors (RMSE) of 0.505 and 0.891, respectively, for the MC predictions of logging residue and sweet sorghum. Partial least squares regression models combined with NIR spectroscopy achieved R² of 0.942 and 0.958 with RMSE of 1.318 and 3.681 for logging residue and sweet sorghum, respectively. In contrast to the electrical resistance-based models, the NIR-based models could predict the MC regardless of the bulk density of the materials. Data transformation by the second derivative and removal of outliers contributed to the improvement of the prediction of the NIR-based models. [ABSTRACT FROM AUTHOR]

Branches remain in the forest environment as logging activity residue. Considering the large size of many Amazonian trees, their branches have considerable dimensions and can contribute to a sustainable wood alternative for various applications. Due to the formation of reaction wood in the branches, relevant macro and ultrastructural changes can occur in its characteristics in relation to the trunk wood. However, the woods of the branches are not technologically well known. Therefore, this work aimed to evaluate the wood quality of branches of Hymenaea courbaril L., comparing it with wood of trunks. The extractives and lignin contents, basic density, shrinkage, fiber biometry, microfibril angle and mechanical resistance to compression parallel to the fibers were analyzed. The branch wood had smaller fiber dimensions and a higher microfibril angle than the trunk wood. The basic density was similar between these materials. The linear and volumetric shrinkages were smaller in the branch wood than in the trunk, while the axial shrinkage was higher in the branch. The parallel compressive strength was also lower in the branch wood than in the trunk. The branch wood has properties suitable for products with higher added value such as furniture, decorative objects, floors and utensils in general. [ABSTRACT FROM AUTHOR]

We determine the economic revenues and optimal forest management of uneven-aged loblolly pine, longleaf pine, and slash pine forests considering timber and carbon benefits in the southeastern United States. Our results show that uneven-aged management of southern pines generates positive total revenues, with the exception of those stands managed with high residual basal areas and long cutting cycles. The uneven-aged management of pine forests is economically more attractive with loblolly pine stands than with longleaf pine or slash pine for all cutting cycles and residual basal areas; on average, loblolly pine returns $1389.60·ha−1 more than slash pine and $1500.70·ha−1 more than longleaf pine for all cutting cycles. For uneven-aged loblolly pine forests, our results suggest that landowners should experience highest profits with the shortest viable cutting cycle (10 years) and a medium-high residual basal area (11.5 m2·ha−1). For uneven-aged longleaf pine forests, landowners would be economically better off with a longer cutting cycle (20 years) and a lower residual basal area (6.9 m2·ha−1). Notably, uneven-aged management of longleaf pine and slash pine for timber production becomes unprofitable with low-medium or high residual basal areas (9.2–11.5 m2·ha−1). [ABSTRACT FROM AUTHOR]

Understanding the role of biocrust-forming mosses in soil recovery after wildfires is necessary for assessing the resilience of managed ecosystems. The purpose of this study was to investigate the mid-term impacts of two contrasting post-fire management strategies on soil recovery in eucalypt plantations in north-central Portugal, where a high cover of biocrust-forming mosses developed post-fire, contributing to erosion control. Six years after a wildfire, we examined the legacy effects of salvage logging and two rates of mulch application using logging residues (a standard rate of 8.0 Mg ha-1 and a reduced rate of 2.6 Mg ha-1) on soil properties, and explored the interaction between moss biocrusts and forest management practices on soils. Our findings reveal the resilience of soils to physical disturbance after logging operations, with no persistent negative effects on their physicochemical properties. Although forest residue mulches showed minimal influence on soils after six years, an interesting interaction with moss biocrusts was observed. In the absence of moss cover, direct contact of wood residues with soil at the standard mulch rate promoted higher nutrient content and biochemical activity, potentially attributed to accelerated decomposition processes. Regardless of the management applied, our study highlights the role of moss biocrusts in improving soil aggregation and biochemical processes in the mid-term. However, the severe water repellency observed in these soils may have impeded further biocrust expansion. Understanding the implications of forest management practices on soil recovery after wildfires is imperative for guiding strategies aimed at promoting ecosystem recovery and resilience in fire-prone managed forest ecosystems. • Soils show resilience to logging with no lasting physicochemical impacts. • Post-fire mulching increased soil nutrient content in the absence of moss biocrusts. • Biocrust proliferation may be conditioned by the severe soil water repellency. • Moss biocrust accelerated post-fire soil recovery and improved soil functions. [ABSTRACT FROM AUTHOR]

Effective regulation of land-use activities in steepland areas is crucial to protect downstream ecologies and human life as intense rainfall disturbances become more frequent globally. In Aotearoa New Zealand extensive synchronous clear-cutting of Pinus radiata monocultures on steep convergent landforms, and associated earthworks, causes ongoing accelerated erosion, excessive sedimentation, and debris-laden landslides after adverse weather events. This study examines the implementation of national forestry regulations established in 2018, which also enable regional councils to create more stringent rules to protect aquatic ecosystems. All sixteen councils were surveyed in 2021 and 2022 for stringency in planning provisions; and four regions seriously affected by Cyclone Gabrielle in 2023 were resurveyed in 2024. The cyclone caused loss of human life and calamitous damage to housing, infrastructure, and productive land uses from floods exacerbated by clearcut logging debris. All councils had administratively adopted the national regulations into their existing freshwater and coastal resource management plans. Twelve councils retained existing rules that conflicted with the regulations, but these rules do not protect all regionally significant aquatic ecosystems nor minimise landslide risks. No council, except Gisborne, had instigated the expensive and lengthy statutory resource management plan change process, nor taken a 'strategic and principled' approach to develop more stringent regulations, such as tougher restrictions on clear-cutting, earthworks, and replanting on steep erosion-prone convergent landforms to protect aquatic ecosystems and vulnerable communities. The government did tighten the management of logging debris after the cyclone, but the national regulations remain ineffective in addressing clear-cut practices maladaptive to intense rainfall and continue to permit replanting on convergent landforms. The regulations need urgent amendment to require councils to develop and implement a strategic and principled approach to stringency to better protect aquatic ecosystems, human life, economic livelihoods, and public infrastructure. Water quality monitoring is also currently inadequate, as no council systematically monitors the effects of forestry activities on sedimentation rates, which inhibits the ability to compare across and between regions. Foresters are not required to monitor water quality, which also stymies assessments of compliance and policy effectiveness. Councils regularly monitor rivers, lakes, and estuaries, but rarely the effects of individual land uses. This means that sediment or other contaminants cannot be parsed to different land use activities, undermining attempts to set catchment limits. It can also take decades at current monitoring levels to defensibly show any water quality improvements after changes to land use regulations. The current environmental limits approach of setting individual water quality attribute targets is highly unlikely to drive changes to maladaptive and ecologically degrading land uses. A new environmental management approach is needed that prohibits or effectively constrains hazardous and adverse activities. • Intense rainfall elevates landslide risk after clear-cutting plantation forests on steeplands. • Restrictions on harvest area, earthworks and replanting can mitigate risks to local communities. • Neoliberal regulators may prefer flexible environmental standards over preventative rules. • Without monitoring by foresters or regulators, standards cannot be analysed for effectiveness. • Regulators may not have data to defend imposing more stringent rules on maladaptive practices. [ABSTRACT FROM AUTHOR]

The biodiversity of fire-dependent woodlands is of great importance and interest throughout the eastern United States but is especially integral to longleaf pine (Pinus palustris) savannahs and woodlands. Longleaf pine communities are widespread throughout the southeastern United States with a dominant understory vegetation of wiregrass (Aristida spp.) in much of its range. Some portions of the longleaf pine range, however, are naturally free of wiregrass including an area in central South Carolina called the "Wiregrass Gap". Here, the understory vegetation is dominated by bluestem grasses (Andropogon spp. and Schizachyrium spp.) which, along with pine (Pinus spp.) and oak (Quercus spp.) litter, drive the disturbance regime of frequent low-intensity fire. The successful establishment of these grasses is key for longleaf pine woodland restoration efforts in this region. We investigated the woodland vegetation response to three slash manipulation treatments that resulted from a restoration harvest in 2020. These consisted of (1) a "conventional" treatment in which the slash was distributed across the treatment area, (2) a "biomass" treatment simulating a timber harvest that removes the whole tree from the site including the slash, and (3) a "mastication" treatment during which the slash and any regenerating woody stems were mulched shortly after the harvest. The biomass treatment generally resulted in a positive herbaceous response with significantly greater graminoid (p = 0.012, 1.5x greater) and non-woody perennial (p = 0.006, 1.5x greater) richness. This herbaceous response was likely driven by greater combined duff and mineral soil exposure yielding more opportunity for herbaceous species to establish. The benefits to the herbaceous layer were likely suppressed by large amounts of woody 100-h fuels in the conventional treatment and 1- to 10-hour fuels in the mastication treatment. While exposed duff and mineral soil had a favorable effect on the herbaceous response, it also benefitted the regeneration of loblolly pine seedlings (39 % of all woody seedling stems on site) with significantly more (p = 0.004, 5.0x as many) in the biomass than the mastication treatment. This complicates restoration efforts as poor continuity of herbaceous fuel in the mastication and biomass treatments could impede the swift re-introduction of prescribed fire. With better fuel continuity to carry a prescribed burn, the conventional treatment could most effectively reduce loblolly pine regeneration. Thus, accepting an initial muted herbaceous response in the conventional treatment could eventually lead to a more robust herbaceous response post-burn. Fire will ultimately determine the treatments' effectiveness. • The manipulation of logging slash influenced pre-fire vegetation. • Slash removal resulted in greater graminoid and non-woody perennial richness. • Slash removal resulted in more loblolly pine seedlings, complicating restoration. • Unreliable fuel continuity with slash removal may complicate swift restoration by fire. [ABSTRACT FROM AUTHOR]

Finally, we note that while SST and CCP estimates are of interest in understanding the age-related dynamics of the forest carbon balance, it is the cumulative NEP over the entire rotation period that describes the carbon sequestration potential of managed forests. Keywords: boreal forest; carbon sequestration; climate change mitigation; rotation-forestry; source-sink trajectory EN boreal forest carbon sequestration climate change mitigation rotation-forestry source-sink trajectory e1 e3 3 07/06/23 20230801 NES 230801 An essential metric for describing carbon dynamics in managed forest landscapes is the recovery time of the carbon balance after clear-cutting. On the uncertainty in estimates of the carbon balance recovery time after forest clear-cutting. [Extracted from the article]

The COVID-19 lock/slow down affected humanity and livelihood, while it showed some positive effects on the environment with improvement in air quality indicators. Though many studies published after COVID-19 first phase lockdown observed reduction in pollutants over India, no studies yet compared the air quality indicators over the two lock/slow down windows during 2020-2021. This study reports results of rapid assessment of seven air quality indicators such as Nitrogen dioxide (NO2), Sulphur dioxide (SO2), Formaldehyde (HCHO), Methane (CH4), Carbon monoxide (CO), Aerosol (Ultraviolet Aerosol Index, UVAI), and Ozone (O3) for the past three years on monthly time scale using TROPOMI (Tropospheric Monitoring Instrument) data on GEE (Google Earth Engine) platform over India, with focus on the Gangetic plain, an air pollution hotspot. Significant reduction in NO2, SO2, HCHO and Absorbing Aerosol Index (AAI) was observed during March-May 2020 as compared to the same period in 2019, while the levels of NO2, SO2, HCHO and CO increased significantly in 2021 compared to March-May 2020. This suggests that COVID-19 lock/slow down in 2020 played a significant role in improving air quality indicators, while the relaxation in 2021 has led to detoriation, compared to 2020. The pyrogenic (forest fire and slash and burn agriculture) and agricultural (wet crop) sources were identified to contaminate the expression of slow/lock down effects on air quality indicators such as HCHO, CO and CH4 over India. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Woody biomass is an important feedstock for renewable energy production in the United States. Residues are produced by forest harvests, and some operations utilize this material for energywood. Energywood requires additional processing and is often the lowest value product generated. Additional research quantifying the productivity and costs of energywood operations could allow stakeholders to evaluate the efficiency of those operations and identify areas for improvement. This study evaluated five energywood harvesting operations in the Lower Mid-Atlantic region of the United States (two Appalachian Mountain harvests and three Coastal Plain harvests). Each harvesting operation was observed for 4–7 days, and productivity data were collected on each harvesting function using time study and activity sampling methods. Productivity and costs of each operation were estimated, and equipment mixes and harvesting methods were evaluated to determine efficiency. Interviews were also conducted with each logging contractor to understand operating strategies and decision making. Cut and haul costs averaged (USD) $32.07/tonne and ranged from $26.19 to $38.28/tonne. Hauling consistently comprised the largest function cost at an average of $12.24/tonne. Machines handling energywood were less productive than those harvesting roundwood because of the large effect average stem size had on productivity levels. Harvesting system analysis also highlighted the importance of ensuring a balanced equipment mix to lower costs and ensure efficiency. This research provides stakeholders with a valuable comparison of energywood harvesting operations in the Lower Mid-Atlantic region of the United States that can be used to make better-informed decisions regarding the efficient and economical harvest of energywood. [ABSTRACT FROM AUTHOR]

[Display omitted] • Agricultural leftovers, animal manure, and municipal waste are surplus biomass Total biogas potential is 2.31 × 104 Mm3, equivalent to 1.29 × 103 PJ of energy. • Biomethane potential is determined from Y Buswel. • For bioethanol, the upstream authentication must be economically viable. • Theoretical and resource assessment data has synergies with estimated potential. Biomass produced from agriculture at present provides most energy services in developing nations. In India, enormous quantities of biomass are produced for conversion into valuable energy. Bioenergy production from agricultural leftovers, animal manure, and municipal waste has the potential to meet of the rising need sustainable energy. It is a practical and sustainable option since the energy produced from the above mentioned sources can minimise the use of fossil fuels, reduce greenhouse gas emissions, and alleviate the effects of climate change. In addition, it can boost marginal and small farmers in terms of income and job opportunities. Evaluating agricultural leftovers, animal manure, and municipal waste as bioenergy resources can provide a method of tapping renewable energy opportunities. It is possible to minimise constraints for using agricultural leftovers, animal manure, and municipal waste, support investment decisions, and maximise the utilisation of biomass resources available. This study is intended to establish the amount of energy demand in India that can be met by using crop residues, animal manure, logging residues, and municipal waste. The annual energy potential of these biomass waste was quantified and assessed in the study. It has been determined that the technical bioenergy potential of these biomass resources is 1.29 × 103 PJ in 2.31 × 104 Mm3 of biogas and 7.79 × 102 PJ in 3.49 × 104 Ml of cellulosic ethanol. However, the country must overcome techno-economic barriers to handle the projects likely to be initiated soon. [ABSTRACT FROM AUTHOR]

Simple Summary: While studies based on the taxonomic facet of biodiversity have already proven their value in understanding soil functioning, studies focusing on the functional facet based on the traits of organisms are scarce in the Ivorian context. Among soil organisms, springtails play an important role in soil functioning and are a useful bioindicator for assessing the impact of land use change and agricultural practices on soil biodiversity. However, their taxonomy is very poorly known in Côte d'Ivoire. The functional trait approach is therefore a relevant alternative for assessing the response of springtails communities to organic matter management in tree plantations. The aim of this study was to determine how different input of organic matter in the form of logging residues and legumes influence the body size and functional diversity of springtails. Our results showed a high functional richness and body size of springtails in the practice with trunks and large branches (R2L1). Functional traits are useful to assess the effects of agricultural practices on springtails communities. We used trait-based approaches to reveal the functional responses of springtails communities to organic matter inputs in a rubber plantation in Côte d'Ivoire. Pitfall traps were used to sample springtails in each practice. The results showed that the total abundance of springtails increased significantly with the amount of organic matter (R0L0 < R2L1). Larger springtails (body length, furca and antennae) were observed in plots with high organic matter. Practices with logging residues and legume recorded the highest functional richness. The principal coordinate analysis showed different functional composition patterns between practices with logging residues (R1L1 and R2L1) and those without inputs (R0L0 and R0L1). This difference in functional composition (PERMANOVA analysis) was related to the effect of practices. These results highlight the pertinence of the functional trait approach in the characterization of springtail communities, a bioindicator of soil health, for organic matter management practice. [ABSTRACT FROM AUTHOR]

The aim of the work was to quantify the mass of logging residues (branches and tops; t yr−1 dry matter, DM) for energy generation starting from Forest Management Plans (FMP) data. The methodology was applied to public stands of an Italian district (area: 3.60 × 104 ha; period: 2009–2018). Compared to the previous preliminary analysis, the potentially available residues were computed considering forest accessibility and road traversability, by combining FMPs data with a geographic information system (GIS). New issues that were assessed here were: (i) representation of stands consisting of multiple disconnected parts; (ii) calculation of producible residues by using different values of biomass expansion factors (Scenario 1, S1; Scenario 2, S2). The potentially available residues computed for the analyzed period were used to quantify the current sustainable supply. Then, the potentially generated heat (thermal energy, TE; GJ yr−1) and electricity (EE; GJ yr−1), and the potentially avoided CO2 emissions into the atmosphere (EM; t yr−1 CO2) related to the final combustion process were computed by assuming that the current supply of residues was used as woodchips in a local centralized heating plant currently operating. For both S1 and S2, the large difference between the potentially producible and the potentially available residues demonstrated that geodata are essential for reliable estimations. Moreover, as the required information for the GIS analysis can be easily found in databases made available by forestry authorities, the proposed approach can be applied also to other areas; this could be helpful to support local decision-makers in defining sustainable practices for residues recovery. [ABSTRACT FROM AUTHOR]

Soil microbial residues play an important role in the formation and stabilization of soil organic matter and can be quantitatively characterized by amino sugars. However, the response of soil microbial residues to agricultural cultivation in karst areas remains unclear. In this study, we collected soil samples from natural reserved land as well as five plantation forests dominated by Citrus trees cultivated for 0, 1, 5, 15, 30 years to examine the effects of agricultural cultivation on the content of microbial residues (amino sugar analysis). Results showed that: (1) Soil Amino Sugars (ASs) contents were significantly reduced after agricultural cultivation along with the sharp decrease in soil organic carbon (SOC). After 30 years of cultivation, the contents of total ASs, glucosamine (GluN), galactosamine (GalN), and muramic acid (MurA) in cultivated soils decreased by 58.22%, 55.30%, 27.11%, respectively, compared with 0 yr.; (2) Microbial residual carbon contribution to SOC increased from 34.11% to 81.33% after 30 years of cultivation, including fungal residual carbon (FRC) (25.79% to 48.6%) and bacterial residual carbon (BRC) (8.32% to 32.72%); (3) Soil GluN/MurA values tended to decrease with increasing cultivation years. The results highlight the significant effect of cultivation years on amino sugar accumulation. It indicates that the years of reclamation in karst areas have different impacts on the organic fractions derived from various microbial communities in the soil organic matter pool, and the microbial residues indicated by amino sugar are of great significance for the interception of soil organic matter. [ABSTRACT FROM AUTHOR]