The impact of fires on forests is determined by a number of factors, including fire type and intensity, forest stand species composition and age structure, soils and other conditions. This paper examines the relationship between fire intensity, assessed using fire radiative power (FRP), and the degree of forest disturbance, assessed through the proportion of tree cover loss. The objectives of this study included the following: 1) analysis of the dynamics of FRP and the proportion of stand-replacement fires in Siberia; 2) assessment of the relationships between FRP and predominant tree species as well as the seasonality and duration of fires and the proportion of stand-replacement fires. MODIS thematic products for 2002–2022 were used to obtain data on the locations and areas of wildfires as well as FRP estimates. These products included MODIS burned area product and MODIS thermal anomalies product containing FRP estimates. The global forest cover change product was used to detect areas where forest loss had occurred. Increasing trends in both the total burned area and the area of stand-replacement fires were observed in the region. A significant increase in stand-replacement fires occurred after the year 2012. The highest proportion of stand-replacement fires was observed in dark coniferous stands (61%) and in larch-dominant stands (52%). Significant increasing trends in FRP were observed in dark coniferous stands (r²=0.6, p < 0.01), larch stands (r²=0.5, p<0.01) and pine stands (r²=0.4, p<0.05). Stand-replacement fires were also characterized by ~14% higher mean FRP values compared to non-stand-replacement fires (~30 vs. ~26 MW/km²). Stand-replacement fires were mainly observed during the second half of summer and were characterized by a longer duration compared to non-stand-replacement fires (3.8 vs. 4.9 days). The results showed that the proportion of stand-replacement fires in Siberia is largely determined by the fire radiative power, fire duration, seasonality, and prevailing forest stands.

Introduction

The research focused on the impact of burned forests on biodiversity and soil layers. The interaction between forests affected by wildfires and the ecological dynamics within forest ecosystems is complex. This complexity is increased by the use, on some occasions, of heavy machinery used in reforestation, which compacts delicate soil. Understanding the effects of wildfires on biodiversity, nutrient cycling, mycorrhizal networks, soil erosion, and forest resilience is key. The goal is to provide information for better conservation and restoration strategies for forests damaged by fire.

Methods

This study used a systematic review of the literature in an important series of databases. The key variables referenced included nutrient cycles, heavy machinery compaction alterations in different mycorrhizal networks, the survival and recovery of resilient trees, and the impact of fire on soil microbial communities. Case studies on natural fire regimes and their impact on biodiversity and forest dynamics were also included.

Results

The results indicate that forest fires significantly alter the cyclic and mycorrhizal networks, affecting the resilience of the forest ecosystem. Fire-induced deforestation can benefit some biodiversity by promoting fire-adapted species. On the contrary, the heavy machinery used in reforestation causes soil compaction, altering the ecological ‘coopetition phenomenon’. The combined stressors of fire and soil compaction make better recovery difficult. However, in contrast, other studies show that controlled burning can mitigate some negative impacts, facilitating the recovery of the mycorrhizal network and improving the regenerative capacity of trees.

Conclusions

Understanding the cumulative effects of wildlife deforestation versus traditional deforestation is essential for developing effective forest conservation and restoration policies. The findings suggest that integrating prescribed burning and sustainable forest management practices into forest management can promote resilience and recovery. Future research should explore the feedback loops between fire regimes, biodiversity, and forest dynamics to refine these strategies further.

Wildfires are the most significant factor that affects the boreal ecosystems of Siberia. The issue of monitoring fire consequences such as tree stand losses, long-term changes in the thermal regime of soils, and direct emissions of carbon is very important for the region. Remote sensing data are the most effective technique for controlling large-scale processes caused by wildfires in Siberia.

Our study used fire data from the satellite monitoring bank (Institute of Forest SB RAS, Krasnoyarsk, Russia) for 1996–2023. Fire intensity was ranged based on the Fire Radiative Power (FRP) technology of MOD14/MYD14 products. We controlled vegetation cover using the “Vega-Pro” GIS service of the Space Research Institute RAS (Moscow, Russia). To evaluate fire emissions, we modified the Seiler–Crutzen method (1980), by accounting for fire intensity in terms of FRP.

We obtained the following results: firstly, we calculated that during 1996–2023, Siberian forests were impacted by 15.48±2.33 thousand fires per year, which is about 11.34±2.88 million hectares of burnt areas annually. Considering fire intensity, we estimated the stand-replacement fires in Siberia at approximately 1.0 million hectares, and this value has the potential to surpass 3.0 million hectares by 2050, given the current trends in burning regimes and fire intensity.

Next, over the two decades of 2002–2022, a growth trend in high-intensity fires was typical for a significant part of Siberia (~30% of the total area), mainly in larch-dominated forests (>60° N) and in the tundra zone (>67° N).

Finally, direct fire emissions have been rising from 60.0±25.8 Tg/year in the early 2000s up to 296.0±102.0 Tg/year during the 2020–2023 seasons due to increases in both wildfire area and the proportion of high-intensity fires. Thus, in the near future, carbon sinks may be suppressed by annual fire emissions, resulting in a positive carbon balance in some ecosystems of Siberia.

This research develops a forest management method to select the optimal intensity of silvicultural intervention aimed to reducing combustion energy load within a forest ecosystem. Since the fuel load is the only modifiable factor in the linear intensity equation of a wildfire, thinnings are essential to prevent or mitigate wildfires. The methodology involves measuring the tree volume within a sample area, determining the volumetric difference per square meter before and after intervention, and calculating the volume of aboveground biomass removed using the specific wood density of the target species. The higher heating value of the species is calculated and multiplied by the removed biomass volume and its specific weight. By comparing pre- and post-intervention values within Byram's equation, the variation in flame front intensity can also be determined. This approach allows forest managers to decide thinning intensity based on fuel load and calorific energy. Results show that systematic thinning reduces potential combustion energy, decreasing wildfire danger and intensity. Additionally, the study calculates the kilograms per square meter of water saved post-intervention compared to what would be needed to extinguish a full-scale forest fire. This method provides a quantifiable approach for tailoring silvicultural interventions, enhancing forest resilience and safety. The data obtained from the spreadsheet is then used within the Q-GIS software to spatialize the calorific energy before and after the intervention using the geostatistical interpolation method known as kriging, which involves obtaining the different intervention scenarios for silvicultural operations. By applying this methodology, forest ecosystems can be managed in a more sustainable and suitable way, effectively balancing ecological health with wild fire prevention.

The presence/distribution of lutetium (Lu) in topsoils from Leicester city and surrounding areas (England) represents a low risk for the population (ingestion and dermal contact); meanwhile, its content in wild mushrooms could present some oral risks. To monitor the air quality, about 2-5 grams were collected from a sample of of bark with a length of 2-6 millimetres from 55 different trees across Leicester and 41 from surrounding rural/suburban areas; samples were taken at 1.50–1.80 metres from the ground to limit contamination from topsoil/dust. Lu was monitored by ICP-MS in cleaned/ground/homogenised samples mineralised with HNO₃/H₂O₂ [LoD=0.066 ng/g dry weight (dw)]. Results were compared with previous studies performed on 106 mushrooms and 850 topsoils collected in the same areas. Levels of Lu were similar in both main areas; data were presented as medians and ranges for urban and rural areas, respectively (in ng/g dw): 0.580 (0.182-2.118) and 0.584 (0.402-1.071). This results are in line with the distribution observed in topsoils, i.e., Lu did not show statistical differences between urban and rural areas (p-value = 0.602; 0.117 vs. 0.123 mg/kg). However, some bark samples collected in the city presented higher levels of this element. This pattern is similar to levels observed in wild mushrooms, in which the higher presence of Lu was detected in mushrooms collected in urban areas (0.347 vs. 0.196 ng/g dw). Results suggest similar sources of air contamination by Lu across the main areas monitored, in which topsoils might play a role that should be further assessed, although these made minor contributions to the levels monitored in wild mushrooms. Although preliminary, in general, levels of Lu found in the tree bark were lower than the natural background reference concentration of Lu reported in plant materials collected in a forest in northwest Germany (2.5-5 ng/g dw), suggesting a minor contamination by Lu in Leicestershire.

Wood is a versatile and remarkable building material that has been utilized for a long time in an assortment of applications. Despite the fact that untreated wood is more prone to deterioration and has less inherent resilience, preservatives are used to prolong the service life of wood. Numerous preservatives are available to extend the durability of wood against deterioration. The environmental concerns associated with first- and second-generation wood preservatives encompassing pentachlorophenol (PCP), chromated copper arsenate (CCA), etc., such as the leaching of preservative chemicals from the treated wood, leads to air, soil, and water contamination and disposal-related issues, which have driven the emphasis on the use of carbon-based third-generation wood preservatives, particularly triazoles. The development of preservative solutions with minimal adverse impacts on human health and the environment has received more attention. In the present study, we investigated the possibility of developing a formulation using organic fungicides (tebuconazole) and inorganic salts (copper sulphate and boric acid), and their efficacy was screened using the petri plate bioassay. At low concentrations, few of the formulations exhibited 100% inhibition against the white rot (Trametes versicolor) and brown rot (Oligoporus placenta) fungi. Additionally, the screened formulation was used in mango wood (Mangifera indica) and exposed to fungal decay. The wooden specimens treated with the screened formulation improved decay resistance. The rResults indicated a gradual reduction in percent weight loss, of 2.37% and 3.39% against white rot and brown rot fungi, in treated samples after exposure. The changes in chemical structure and microstructure after exposure to fungi were studied using Fourier transform infrared spectroscopy and scanning electron microscopy techniques. The potential effect of organic fungicide incorporated with inorganic salts increases resistance against fungi. Further SEM micrographs and FTIR spectroscopic analysis of decayed wood confirmed less degradation in treated wood compared to untreated specimens.

Lignin is one of the three major components of the cell wall of lignocellulosic biomaterials. It is the second-most abundant polymer in nature. It is a complex and heterogeneous polymer found in the cell walls of lignocellulosic biomass. Lignin’s predominant composition, rich in carbon and aromatic structures, enhances its value by enabling the development of high-value chemicals and bio-based materials. As one of the most affluent natural renewable sources of aromatic structures and the world’s second-largest renewable source of carbon, lignin possesses a thermal value comparable to that of carbon. Its aromatic constituents exhibit unique chemical properties and significant bioactive effects, making lignin a crucial material in various advanced applications. Different chemical fractionation methods have been designed to overcome the lignocellulosic biomass’ obstacle to extracting lignin biopolymer. Lignin fractionation is a process that involves separating lignin from other components of biomass feedstocks, such as cellulose and hemicellulose. This process is commonly used in the paper and pulp industry to obtain valuable lignin derivatives that can be used in various applications, including, among others, biofuels, chemicals, and biomaterials. In this review, we provide a comprehensive chemical overview of current processes for extracting technical lignins from wood and lignocellulosic biomass, critically evaluating the advantages and limitations of each method.

The invasion of exotic plants threatens biodiversity, affecting ecosystem services and ecological processes in native ecosystems. Road construction creates new environments and contributes to the introduction and spread of exotic and invasive plants. This study aimed to analyze the contribution of different functional groups (annual herbs and grasses, perennial herbs and grasses, shrubs, trees) to the invasion of exotic species on roadside cut slopes in the Austrocedrus chilensis forest in northwest Andean Patagonia, Argentina. Roadside slopes (RSs) and nearby reference areas (RAs) were selected, and the cover of native, exotic, and invasive species from the functional groups was evaluated in 1 m² plots using the Braun-Blanquet method. It was found that invasive perennial herbs and grasses predominated on RS, with a cover (19.6±3.0%) higher than that of RA (8.9±1.5%). Agrostis capillaris and Rumex acetosella were the most abundant invasive species. Among native species, shrubs and perennial herbs and grasses were predominant on RS, with Baccharis rhomboidalis and Acaena pinnatifida being the most abundant. This study demonstrates that the roadside slopes of the Austrocedrus chilensis forest harbor invasive exotic species that can invade nearby natural areas. Early detection of these species is important for proper management and control, thus promoting the conservation of biodiversity in forest environments.

The advancement of Light Detection and Ranging (LiDAR) technology has revolutionized forest inventory practices by providing precise and detailed data on forest structure. This study aims to compare the accuracy, efficiency, and cost-effectiveness of two LiDAR platforms, Unmanned Aerial Vehicles (UAV) LiDAR and Handheld Mobile Laser Scanners (MLS), in capturing key forest inventory parameters such as stem mapping, diameter at breast height (DBH), and tree height. This study was conducted in a pine forest located in Chalkidiki, Greece. LiDAR data were collected using UAV LiDAR (DJI Matrice 350 RTK with Zenmuse L2) and a Handheld Mobile Laser Scanner (Leica BLK2GO) over the same forest plots. Additionally, manual measurements were conducted to serve as ground truth data. The raw LiDAR data were processed to extract forest inventory parameters, including point-cloud classification, segmentation, and parameter extraction. The platforms were compared based on data accuracy, time efficiency, ease of use, and cost, with statistical analyses performed to evaluate the differences in measurements obtained from each platform against ground truth data. Preliminary results indicate that both LiDAR platforms can effectively capture forest inventory parameters, but with varying degrees of accuracy and efficiency. UAV LiDAR demonstrated high efficiency and coverage, particularly in capturing canopy structure. The handheld mobile laser scanner offered flexibility and detailed ground-level measurements, providing more information below the canopy, but was strongly affected by complex terrain. These technologies offer significant potential for creating comprehensive 3D forest structure models, which are essential for future forest inventories in Greece and can aid in sustainable forest management.

Introduction: The North-Western Himalayan Region (NWHR) in India comprised of two states, Uttarakhand and Himachal Pradesh and two union territories of Ladakh and Jammu and Kashmir. The NWHR forest is rich in biodiversity, hosting a variety of plant species. The floristic account of forest type in N.W. Himalayas is divided it into four climatic zones viz., Tropical zone, Subtropical zone, Temperate zone and Alpine zone. Nutrient dynamics is broadly defined as the way nutrients are taken up, retained, transferred, and cycled over time and distance, in an ecosystem.

Methods: The data were gathered from various published studies on the NWHR through various databases. These studies were carefully reviewed in detail and presented.

Results: Various factors affect nutrient dynamics in forests including climate, soil, vegetation, topography, soil microbes and natural and anthropogenic disturbances. Nutrient dynamics in forest ecosystem can be understood through nutrient in forest soil, litter decomposition, throughfall, stemflow and nutrients in different plant parts. The studies of major soil nutrients (NPK) in North-Western Himalaya show variation with respect to different forest types, soil depth, altitude and season. Variation in litter production, decomposition and nutrient content is also observed among different forest types. Thorughfall, stemflow, nutrient uptake in different parts of trees and nutrient re-translocation also shows variation among different tree species.

Conclusion: Understanding the cycling of nutrients, such as nitrogen, phosphorus, and potassium helps maintain soil fertility, supports diverse plant species, and contributes to overall ecosystem resilience.