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Apricot trees, serving as critical agricultural resources, hold a significant role within the agricultural domain. Conventional methods for detecting pests and diseases in these trees are notably labor-intensive. Many conditions affecting apricot trees manifest distinct visual symptoms that are ideally suited for precise identification and classification via deep learning techniques. Despite this, the academic realm currently lacks extensive, realistic datasets and deep learning strategies specifically crafted for apricot trees. This study introduces ATZD01, a publicly accessible dataset encompassing 11 categories of apricot tree pests and diseases, meticulously compiled under genuine field conditions. Furthermore, we introduce an innovative detection algorithm founded on convolutional neural networks, specifically devised for the management of apricot tree pests and diseases. To enhance the accuracy of detection, we have developed a novel object detection framework, APNet, alongside a dedicated module, the Adaptive Thresholding Algorithm (ATA), tailored for the detection of apricot tree afflictions. Experimental evaluations reveal that our proposed algorithm attains an accuracy rate of 87.1% on ATZD01, surpassing the performance of all other leading algorithms tested, thereby affirming the effectiveness of our dataset and model. The code and dataset will be made available at https://github.com/meanlang/ATZD01. [ABSTRACT FROM AUTHOR]

Poly(butylene succinate-co-adipate) (PBSA), a biodegradable plastic, is significantly colonized and degraded by soil microbes under natural field conditions, especially by fungal plant pathogens, raising concerns about potential economic losses. This study hypothesizes that the degradation of biodegradable plastics may increase the presence and abundance of plant pathogens by serving as an additional carbon source, ultimately posing a risk to forest ecosystems. We investigated (i) fungal plant pathogens during the exposure of PBSA in European broadleaved and coniferous forests (two forest types), with a specific focus on potential risk to tree health, and (ii) the response of such fungi to environmental factors, including tree species, soil pH, nutrient availability, moisture content, and the physicochemical properties of leaf litter layer. Next-generation sequencing (NGS) revealed that PBSA harbored a total of 318 fungal plant pathogenic amplicon sequence variants (ASVs) belonging to 108 genera. Among the identified genera (Alternaria, Nectria, Phoma, Lophodermium, and Phacidium), some species have been reported as causative agents of tree diseases. Plenodomus was present in high relative abundances on PBSA, which have not previously been associated with disease in broadleaved and coniferous forests. Furthermore, the highest number of fungal plant pathogens were detected at 200 days of PBSA exposure (112 and 99 fungal plant pathogenic ASV on PBSA degraded under Q. robur and F. sylvatic-dominated forest, respectively), which was double compared mature leaves and needles from the same forest sites. These findings suggest that PBSA attracts fungal plant pathogens in forests as an additional carbon source, potentially leading to increased disease outbreaks and disrupting the stability of forest ecosystems. The fungal plant pathogenic community compositions were mainly shaped by forest type, PBSA exposure time, site locations, leaf litter layer water content, and N:P ratio from leaf litter layer in both forest types. This study provides valuable insights into the potential risks posed by biodegradable plastic degradation in forests after 200 and 400 days of exposure, respectively. Further comprehensive evaluations of their effects on tree health and ecosystems, ideally on a long-term basis, are needed. These evaluations should include integrating microbial investigation, soil health monitoring, and ecosystem interaction assessments. Nevertheless, it should be noted that our interpretation of plant pathogens is solely based on high-throughput sequencing, bioinformatics, and annotation tools. [ABSTRACT FROM AUTHOR]

Fine root traits span two independent axes of variation, the conservation and collaboration axes, which define the root economic space (RES). However, whether early‐stage fine root decomposition rates (quantified as proportion mass loss, i.e. pml) are more strongly related to collaboration or conservation traits remains unclear.We studied 63 tree species in New Zealand's temperate rain forest. We determined the phylogenetic signal in pml and fine root traits, conducted phylogenetic principal component analysis and used phylogenetic generalized least squares to determine which traits are most strongly related to pml.Root decomposition exhibited a high phylogenetic signal and was more strongly related to the conservation than the collaboration axis. Root tissue density (RTD) was negatively correlated and root nitrogen (RN) was positively correlated with pml. Root diameter was positively yet weakly correlated with pml, but specific root length was uncorrelated with pml. The lignin‐to‐N ratio and root cellulose were the strongest predictors of pml.Synthesis: Early‐stage fine root decomposition is most strongly driven by tissue quality traits, such as root nitrogen, tissue density and lignin‐to‐N ratio, which all align with the conservation axis of the root economics space. However, root diameter plays a weak yet undeniable role in early‐stage fine root decomposition. Some thick‐rooted species decomposed faster, possibly due to the higher quality cortical tissue. Thin‐rooted species decomposed slower, possibly because of their higher cellulose concentration that maintains the structural integrity of small diameter roots. Relationships between decomposition and other traits that align with the collaboration gradient deserve further study across the phylogeny of vascular plants. [ABSTRACT FROM AUTHOR]

The effects of microenvironmental conditions on decomposition and its interaction with the mesofauna community remain poorly understood. Therefore, our study aimed to answer the following questions: Does the microenvironment influence the decomposition of Eucalyptus leaf litter and the mesofauna community associated with this process? To do so, we evaluated the litter when exposed to an Eucalyptus plantation (EP) environment and a native forest (NF) environment. Senescent leaves were collected at the base of tree crowns in both the EP and NF environments. After collection, 10 g portions of the dried leaves were placed in litter bags, which were then distributed over the litter in both environments. This defined three treatments: Eucalyptus leaves in the plantation environment, Eucalyptus leaves in NF condition, and NF leaves in their original environment. The litterbag collections took place at 30, 90, 120, 180, 240, and 330 days after installation. Thus, the remaining mass percentages, decomposition rates, and half‐life of the leaf litter were estimated from the dry mass results. The edaphic mesofauna community associated with the decomposition process was evaluated at 30, 90, and 120 days using the Berlese–Tullgren funnel method. The microenvironmental conditions of the native forest promoted a higher decomposition rate of Eucalyptus litter, in addition to greater abundance and richness of mesofauna organisms in relation to the Eucalyptus leaf material in the plantation environment. [ABSTRACT FROM AUTHOR]

Summary: Bark serves crucial roles in safeguarding trees physically and chemically, while also contributing to nutrient cycling and carbon sequestration. Despite its importance, the broader biogeographical patterns and the potential factors influencing bark C : N : P stoichiometry in forest ecosystems remain largely unknown.In this study, we compiled a comprehensive dataset comprising carbon (C), nitrogen (N), and phosphorus (P) concentrations in bark with 1240 records from 550 diverse forest sites to systematically analyze the large‐scale patterns and the factors controlling bark C : N : P stoichiometry.The geometric means of bark C, N, and P concentrations were found to be 493.17 ± 1.75, 3.91 ± 0.09, and 0.2 ± 0.01 mg g−1, respectively. Correspondingly, the C : N, C : P, and N : P mass ratios were 135.51 ± 8.11, 3313.19 ± 210.16, and 19.16 ± 0.6, respectively. Bark C : N : P stoichiometry exhibited conspicuous latitudinal trends, with the exception of N : P ratios. These patterns were primarily shaped by the significant impacts of climate, soil conditions, and plant functional groups. However, the impact of evolutionary history in shaping bark C : N : P stoichiometry outweigh climate, soil, and plant functional group, aligning with the biogeochemical niche (BN) hypothesis.These finding enhance our understanding of the spatial distribution of bark nutrient stoichiometry and have important implications for modeling of global forest ecosystem nutrient cycles in a changing environment. [ABSTRACT FROM AUTHOR]

Soil fauna play an important role in litter decomposition and affect the "home-field advantage" (HFA) of litter decomposition. However, how this effect is modulated by the microenvironment needs further investigation. We conducted a reciprocal transplant experiment of litter decomposition using different mesh-size litterbags across litter and soil layers in subtropical coniferous (Pinus massoniana) and broad-leaved (Quercus variabilis) forests. Our results revealed a pronounced HFA in P. massoniana. P. massoniana litter decomposed faster in its home habitat by 40.6% in the litter layer and 10.2% in the soil layer in coarse mesh bags and by 21.8% in the litter layer and 21.4% in the soil layer in fine mesh bags. However, Q. variabilis litter showed faster decomposition in its home soil layer by 10.8% and 4.3% for coarse and fine mesh bags, whereas in the litter layer it decomposed faster in the away habitat by 16.7% and 20.6% for coarse and fine mesh bags, respectively. Higher soil mesofauna abundance and microbial activities in the coniferous forest compared to the broad-leaved forest drive the observed HFA of litter decomposition. Especially in the litter layer, the abundance of mesofauna was 89.8% higher in the coniferous forest. Coarse mesh bags generally facilitated a higher decomposition rate across litter and soil layers, likely due to a better interaction between soil mesofauna and extracellular enzyme activity. The HFA index exhibited distinct seasonal fluctuations, peaking in October for coarse mesh bags and in April for fine mesh bags within the litter layer, while soil layer peaks occurred in August and April. Notably, an increase in Acarina abundance strongly correlated with enhanced decomposition and HFA effects in the litter layer during October. This study revealed the sensitivity of HFA to the soil layer and soil fauna and underscores the complex role of the microclimate in shaping interactions among soil microorganisms, litter quality, and mesofauna, thereby enriching our understanding of litter decomposition dynamics in forest ecosystems. [ABSTRACT FROM AUTHOR]

Documenting floristic diversity, its natural history traits and habitat affiliation offers crucial insights for developing conservation strategies and management plans for regional biodiversity. In this study, we employed random sampling technique to investigate the floristic composition, natural history trait diversity and habitat distribution among 12 major forest types spread across an elevational gradient of 350–3450 m a.s.l. in the western Himalayan region of Jammu and Kashmir. We recorded 451 species belonging to 90 families in the study region, with herbaceous growth form, perennial life span and therophyte categories dominant. We observed a steady increase in species richness from 800 to 2000 m a.s.l., with highest at 1750 m a.s.l. in the Himalayan dry temperate forest type and then a decreasing trend with elevation. In terms of species turnover, the lowest dissimilarity of 36.8% was found between the Himalayan dry temperate and Fir forests. Whereas, considering species replacement (βsne), the highest similarity of 17.3% was found between the lower western Himalayan and Himalayan dry temperate forests. This shows that beta‐diversity patterns between different forest types are mostly driven by species replacement. Multivariate analysis revealed three major groups in the entire forest species pool. Habitat‐wise, 34% species were recorded in the natural habitats, while the remaining 66% were found in human‐modified habitats (roadsides, piospheres). Our findings will improve scientific understanding of the forest vegetation of this Himalayan region and help in guiding forest policy and management. [ABSTRACT FROM AUTHOR]

Many sampling and analytical methods can estimate the abundance, distributions, and diversity of birds and other wildlife. However, challenges with sample size and analytical capacity can make these methods difficult to implement for resource‐limited monitoring programs. To apprise efficient and attainable sampling designs for landbird monitoring programs with limited observational data, we used breeding season bird point survey data collected in 2016 at four forest restoration sites in Indiana, USA. We evaluated three subsets of observed species richness, total possibly breeding landbirds, Partners in Flight Regional Conservation Concern (PIF RCC) landbirds, and interior forest specialists (IFSs). Simulated surveys based on field data were used to conduct Bayesian Michaelis–Menten curve analyses estimating observed species as a function of sampling effort. On comparing simulated survey sets with multiple habitat types versus those with one habitat, we found that those with multiple habitat types had estimated 39%–83% greater observed PIF RCC species richness and required 41%–55% fewer visits per point to observe an equivalent proportion of PIF RCC species. Even with multiple habitats in a survey set, the number of visits per point required to detect 50% of observable species was 30% higher for PIF RCC species than for total breeding landbird species. Low detection rates of IFS species at two field sites made precise estimation of required effort to observe these species difficult. However, qualitatively, we found that only sites containing mature forest fragments had detections of several bird species designated as high‐confidence IFS species. Our results suggest that deriving specialized species diversity metrics from point survey data can add value when interpreting those data. Additionally, designing studies to collect these metrics may require explicitly planning to visit multiple habitat types at a monitoring site and increasing the number of visits per survey point. Integr Environ Assess Manag 2024;20:1954–1968. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. Key Points: Four forest restoration sites in Indiana supported a variety of potentially breeding migratory bird species, including interior forest specialists and regional conservation concern species.At forest restoration sites in Indiana with various habitat types, it was necessary to visit both open and woody plant‐dominated habitats to efficiently detect bird species of regional conservation concern.When analyzing bird point survey data, deriving specialized species diversity metrics, such as richness of habitat specialist species or conservation concern species, can add value when interpreting those data. [ABSTRACT FROM AUTHOR]

Rill erosion, mostly affecting steep and long hillslopes, is one of the most severe effects of deforestation and wildfires in natural ecosystems. Specific monitoring and accurate but simple models are needed to assess the impacts of these forest disturbances on the rill detachment process. To address this need, this study has simulated the rill detachment capacity (Dc) through flume experiments on samples of soils collected in hillslopes after deforestation and severe burning. The associations between Dc and organic matter (OM) and the aggregate stability of soil (WSA), two key parameters influencing the rill detachment process, have also been explored under the two soil conditions (deforested and burned soils) using multivariate statistical techniques. Finally, linear regression models to predict Dc from these soil parameters or the hydraulic and morphological variables (water flow rate, WFR, and soil slope, S), set in the flume experiments, have been proposed for both soil conditions. Higher Dc in samples from deforested sites compared to the burned soils (+35%) was measured. This Dc increase was associated with parallel decreases in OM (−15%) and WSA (−34%) after deforestation compared to the wildfire-affected sites. However, the discrimination in those soil properties between the two soil conditions was not sharp. Accurate linear equations (r2 > 0.76) interpolating Dc and the shear stress (τ) have been set to estimate the rill erodibility (Kr) to evaluate soil resistance in erosion models to be applied in deforested or burned sites. [ABSTRACT FROM AUTHOR]

Increased wildfire activity is the most significant natural disturbance affecting forest ecosystems as it has a strong impact on their natural recovery. This study aimed to investigate how burn severity (BS) levels and climate factors, including land surface temperature (LST) and precipitation variability (Pr), affect forest recovery in the Middle Volga region of the Russian Federation. It provides a comprehensive analysis of post-fire forest recovery using Landsat time-series data from 2000 to 2023. The analysis utilized the LandTrendr algorithm in the Google Earth Engine (GEE) cloud computing platform to examine Normalized Burn Ratio (NBR) spectral metrics and to quantify the forest recovery at low, moderate, and high burn severity (BS) levels. To evaluate the spatio-temporal trends of the recovery, the Mann–Kendall statistical test and Theil–Sen's slope estimator were utilized. The results suggest that post-fire spectral recovery is significantly influenced by the degree of the BS in affected areas. The higher the class of BS, the faster and more extensive the reforestation of the area occurs. About 91% (40,446 ha) of the first 5-year forest recovery after the wildfire belonged to the BS classes of moderate and high severity. A regression model indicated that land surface temperature (LST) plays a more critical role in post-fire recovery compared to precipitation variability (Pr), accounting for approximately 65% of the variance in recovery outcomes. [ABSTRACT FROM AUTHOR]

Understanding how climate change influences the geographical distribution of species within an ecological niche is essential for predicting habitat shifts and informing conservation efforts. This study evaluates the impact of climate change on habitat suitability and ecological connectivity of wych elm (Ulmus glabra Huds.) in Türkiye. The study explores the future distribution of U. glabra and how its connectivity is affected by habitat fragmentation arising from changing climatic conditions. Contextually, this paper aims to achieve two primary objectives: estimating the potential geographical ranges of U. glabra under different climate scenarios and assessing alterations in ecological connections between current and future habitats. The maximum entropy (MaxEnt) model was used along with Morphological Spatial Pattern Analysis (MSPA), and the Probability of Connectivity (PC) index was applied to show possible transformations in distribution patterns of U. glabra over time. The findings suggest that there will be a reduction in the suitability of locations for the species. Moreover, it is expected that under future climate scenarios, ecological connectivity will decline, especially from 2061 to 2100 in the SSP585 scenario. Notably, significant alterations are anticipated during the latter half of the twenty-first century, mainly outside the coastal areas of the Black Sea, where extensive regions would become unsuitable. Additionally, the species is projected to shift its range, decreasing its presence in inland regions while expanding along the coasts. The results show the vulnerability of this species against climate change, thereby demanding adaptive conservation measures to preserve it within the forest ecosystems of Türkiye. [ABSTRACT FROM AUTHOR]

Since its introduction into Europe in the first half of the 20th century, Cryphonectria parasitica has been gradually spreading across the natural range of the sweet chestnut (Castanea sativa Mill.), infecting the trees and causing lethal bark cankers. Serendipitously, a hyperparasitic Cryphonectria hypovirus 1 (CHV1), which attenuates C. parasitica virulence in combination with more tolerant European chestnut species, was able to ward off the worst effect of the disease. In North America, unfortunately, the native Castanea dentata is now functionally extinct since it occurs only as root sprouts in eastern deciduous forests where it was once dominant. In our work, we investigated changes in C. parasitica populations over time and the regional variability in chestnut populations' tolerance toward the blight disease. While vegetative compatibility (vc) type diversity and prevalence of hypovirulence remained similar as in previous studies, in the Buje population, unlike in previous studies, we were unable to find any hypovirulent fungal strains. The most common vegetative compatibility types (vc types) were EU-1, EU-2 and EU-12. However, several rare EU-types were found, including one previously unreported: EU-46. By inoculating several C. parasitica strains on tree stems from several chestnut populations, we observed that the induced lesion size was affected by the type of inoculum (CHV1-free or CHV1-infected), genotype-related individual chestnut stem and chestnut stem population of origin-related variability. The largest lesions were induced by CHV1-free fungal isolate DOB-G: 20.13 cm2 (95% C.I. 18.10–22.15) and the smallest by CHV1-infected L14/EP713: 2.49 cm2 (95% C.I. 1.59–3.39). Surprisingly, the size of the lesions induced by other CHV1-infected strains fell somewhere in between these extremes. The size of induced lesions was dependent on the population of origin as well and ranged from 11.60 cm2 (95% C.I. 9.87–13.33) for stems from the Moslavačka gora population to 17.75 cm2 (95% C.I. 15.63–19.87) for stems from Ozalj. [ABSTRACT FROM AUTHOR]

Adaptive governance of areas set aside for future protection of biodiversity, sustainable production, and recreation requires knowledge about whether and how effects of area protection are modulated by climate change and redistribution of species. To investigate this, we compare biodiversity of plants (assessed using vegetation plots) and arthropods (collected with Malaise traps, analyzed using metabarcoding) and productivity (tree growth, determined using dendrochronology) in protected and non-protected oak (Quercus spp.) forests along a latitudinal gradient (55.6 °N – 60.8 °N) in Sweden. We also compare historical, recent and projected future climate in the region. In contrast to established global latitudinal diversity gradients, species richness of plants and arthropods increased northwards, possibly reflecting recent climate-induced community redistributions, but neither was higher in protected than in non-protected areas, nor associated with contemporary ground temperature. Species composition of arthropods also did not differ between protected and non-protected areas. Arthropod biomass increased with latitude, suggesting that the magnitude of cascading effects mediated via their roles as pollinators, herbivores, and prey for other trophic levels, varies geographically and will change with a moving climate. Annual growth rate of oaks (an ecosystem service in the form of biomass increase and carbon sequestration) was independent of latitude and did not differ between protected and non-protected areas. Our findings question the efficacy of contemporary designation and management of protected oak forests, and emphasize that development and implementation of modified climate smart conservation strategies is needed to safeguard ecosystem functioning, biodiversity, and recreational values of protected forest areas against future challenges.

Over the past decades, anthropogenic disturbance of geological structures has been significantly documented in Slovakia, mainly driven by the national economy’s demand for mining resources. Among these resources, brown coal, primarily mined in the Upper Nitra coal basin in the Prievidza district (Slovakia), has been essential. Mining activities around town of Handlová, and villages of Koš, Cígeľ and Sebedražie, particularly at the Cígeľ coal mine, have induced several geological defects. These defects, characterised by large cracks and local landslides, disrupt the hydrogeological conditions, significantly impacting the soil water regime stability of the forest ecosystems in these damaged areas. This study investigates the variability and dynamics of the soil water potential in a mining-affected site (Račkov laz) compared to an intact reference area (Čertove chodníky) between 2020 and 2022. Our findings suggest that mining activities could have substantial implications for the soil water regime and, consequently, the ecological stability of forest ecosystems.

Open-cast mining of rock materials provides many essential resources for industry and construction; however, it also significantly impacts the natural environment surrounding the mining sites. The most severe environmental threats posed by open-cast mining of rock materials include land occupation and often associated deforestation, changes in the hydrological regime of the area, emissions of gaseous and particulate pollutants into the atmosphere, noise emissions, and many others. This study aimed to investigate the extent and scope of the impact of a quarry located in southern Poland on the growth and degree of defoliation of trees in the surrounding forest ecosystem, and to examine how dust deposition on the forest floor changes. Additionally, the study examined how the quarry affects the development of natural forest regeneration and the species composition of ground vegetation. For this purpose, two 140 -- meter transects were established in the field, divided into four plots, with the centers located at 10, 50, 90, and 130 meters from the quarry edge. On these plots, the diameter at breast height (DBH) and height of the trees were measured, and their degree of defoliation was assessed. The understory trees were inventoried (divided into three height categories), and the contents of Al and Fe (in addition to silicon, these elements are present in diabase in the highest concentrations) in the litter was determined to assess dust deposition. Furthermore, phytosociological surveys were conducted in the plots, and each plant was assigned an appropriate light indicator value (Ecological Indicator Value). The study showed significant differences in the concentrations of Al and Fe in litter between plots, and a clear decreasing trend in the concentration of these elements with increasing distance from the quarry was observed. Trees closer to the quarry had smaller DBHs and a higher degree of defoliation, although these differences were not statistically significant. The number of understory plants in the highest height class decreased with increasing distance from the quarry. The phytosociological surveys indicated that the light requirements of plants increased with distance from the quarry. Overall, this study found that open-cast mining activities affected the surrounding forest ecosystems, and that the greatest threat posed by the quarry operations was the dust deposition on the forest floor. This phenomenon could possibly be significantly reduced by implementing a properly shaped ecotone zone. [ABSTRACT FROM AUTHOR]

The spatial variability of CO2 and CH4 fluxes at two experimental carbon supersites with non-uniform vegetation and complex topography located in the Krasnodar krai and the Chechen Republic is estimated based on the results of field measurements and model experiments. The results show a significant spatial heterogeneity of the wind speed, turbulent coefficient, and vertical CO2 and CH4 fluxes. It is influenced by complex topography and mosaic vegetation, as well as by an uneven distribution of CO2 and CH4 sources and sinks in vegetation and soil cover. It has been shown that on the summer days of 2022 in similar weather conditions, both experimental sites served as sinks of greenhouse gases: the Roshni-Chu forest area in the Chechen Republic absorbed 5.18 g CO2e/(m2 hour), while the Black Sea coastal area in the Krasnodar krai absorbed only 2.95 g CO2e/(m2 hour). [ABSTRACT FROM AUTHOR]

The aim of the present study is to provide basic information on the biogenicity of the studied soils, to track the change in the microbial populations of A and B horizons, as well as to determine the impact of environmental factors on the microbial abundance of forest soils in the light of ecological forest management. The present study examines six soil profiles in Western Stara Planina Mountain. Soils are defined as Luvisols. For determination of total microbial number and the amount of individual microbiological groups (spore-forming bacteria, non-spore-forming bacteria, actinomycetes and fungi) the standard method of serial dilutions and subsequent inoculation was used. The results are reported in Colony-forming unit (CFU). Standard laboratory analyzes were used to measure the physical and chemical parameters of the soil. A horizon has a greater microbial abundance (from 13.32 and 50.69 × 105 CFU g/dry soil) than B horizon (1.81 to 6.24 69 × 105 CFU g/dry soil). In relation to the A horizon, the most strongly influencing factor is the content of total nitrogen (r = 0.76), followed by pH (0.72) and organic carbon content (0.55). According to the B horizon, these indicators show no correlation. In the A horizon, mechanical composition and density do not correlate with total microbial numbers. In the B horizon mechanical composition and soil density have an impact on biogenicity. With highly compacted soil (bulk density above 1.3 g/cm³), suppression of the soil microbiota is observed. There are no clear dynamics in the redistribution of the percentage participation of microbial groups at depth. [ABSTRACT FROM AUTHOR]

Direct trophic links between aboveground and belowground animal communities are rarely considered in food web models. Most invertebrate animals inhabiting aboveground space eventually become prey of soil predators and scavengers forming a gravity-driven spatial subsidy to detrital food webs, but its importance remains unquantified. We used laboratory-grown 15N-labeled Collembola to trace the incorporation of arthropod rain into soil food webs. Live or euthanized Collembola were supplemented once to field mesocosms in the amount equivalent to the mean daily input of the arthropod rain (19 mg d.w. m−2). After the addition of live Collembola, the isotopic label was found most often in predatory Trombidiformes (83% of samples) and Mesostigmata mites (85%), followed by Araneae (58%), Chilopoda (45%), and Coleoptera (29%). Among non-predatory groups, the isotopic label was recorded in Thysanoptera (27%), Collembola (24%), and Oribatida (18%). The 15N-label was also detected in Symphyla, Formicidae, Diplura, Diplopoda, Opiliones, Diptera, Hemiptera, Oligochaeta, and Nematoda. There was a positive correlation between natural 15N abundance and the frequency of the isotopic label among predators, but not among decomposers. In the non-replicated treatment, in which dead collembolans were added, the label was found in predators and decomposers in approximately equal proportions (21–25%). Unlike other forms of the aboveground subsidy (such as leaf litter, frass, or honeydew) that are primarily processed by microorganisms, arthropod rain is assimilated directly by the animals. The high frequency of consumption of the aboveground subsidy suggests that it plays a significant role in maintaining the abundance of soil predators. [ABSTRACT FROM AUTHOR]

Forest ecosystems face increasing drought exposure due to climate change, necessitating accurate measurements of vegetation water content to assess drought stress and tree mortality risks. Although Frequency Domain Reflectometry offers a viable method for monitoring stem water content by measuring dielectric permittivity, challenges arise from uncertainties in sensor calibration linked to wood properties and species variability, impeding its wider usage. We sampled tropical forest trees and palms in eastern Amazônia to evaluate how sensor output differences are controlled by wood density, temperature and taxonomic identity. Three individuals per species were felled and cut into segments within a diverse dataset comprising five dicotyledonous tree and three monocotyledonous palm species on a wide range of wood densities. Water content was estimated gravimetrically for each segment using a temporally explicit wet-up/dry-down approach and the relationship with the dielectric permittivity was examined. Woody tissue density had no significant impact on the calibration, but species identity and temperature significantly affected sensor readings. The temperature artefact was quantitatively important at large temperature differences, which may have led to significant bias of daily and seasonal water content dynamics in previous studies. We established the first tropical tree and palm calibration equation which performed well for estimating water content. Notably, we demonstrated that the sensitivity remained consistent across species, enabling the creation of a simplified one-slope calibration for accurate, species-independent measurements of relative water content. Our one-slope calibration serves as a general, species-independent standard calibration for assessing relative water content in woody tissue, offering a valuable tool for quantifying drought responses and stress in trees and forest ecosystems. [ABSTRACT FROM AUTHOR]

Purpose: Forest ecosystems are crucial for maintaining high levels of bacterial diversity and containing high amounts of carbon (C), both of which play essential roles in regulating C cycling in the soil and atmosphere through the processes of soil respiration and plant photosynthesis. However, how bacterial communities and different soil carbon components (e.g., soil organic carbon (SOC), readily oxidizable organic carbon (ROC), dissolved organic carbon (DOC), and microbial biomass carbon (MBC)) impact the soil respiration remains largely unknown. Therefore, we hypothesize that belowground bacterial communities and soil carbon contribute to soil respiration, which further influences soil carbon storage. Methods: We collected 24 soil samples from Mount Lu (subtropical forest ecosystem, China) along an elevation gradient consisting in eight levels. Here, we used high-throughput sequencing to detect bacterial alpha and beta diversity. We also measured several soil carbon variables, including SOC, ROC, DOC, and MBC. Particularly, regression analysis, structural equation modeling and random forest analysis were applied to explore the effects of bacterial diversity and soil carbon on soil respiration using R-3.6.2. Results: The results showed that soil respiration has a clearly positive linear regression (R2 = 0.35–0.61, p < 0.01) with all measured soil carbon components, including SOC, ROC, DOC, and MBC. Bacterial communities composition was significantly divergent along the elevation levels, primarily due to species replacement. Random forest and structural equation modeling analysis confirmed that soil carbon and bacterial beta diversity were the significant driving forces behind soil respiration. Additionally, bacterial communities composition significantly impacted changes in soil respiration, with five identified rare bacterial phyla (WPS-2, Gemmatimonadetes, Verrucomicrobia, Planctomycetes, and Cyanobacteria) significantly correlated with soil respiration. Meanwhile, random forest regression analysis showed that rare bacterial taxa, rather than abundant ones, were the primary bacterial predictors of soil respiration. Conclusion: Taken together, belowground bacterial communities and soil carbon variables jointly contribute to soil respiration in a subtropical forest, and further regulate soil C storage as well as even influence climate change. [ABSTRACT FROM AUTHOR]

As the largest carbon reservoir within terrestrial ecosystems, forest ecosystems play a major role as carbon sinks in the global carbon cycle. There are still some uncertainties regarding the responses of different carbon fluxes to environmental changes in cold temperate climate forest ecosystems. Here, 14 cold temperate forest flux sites for at least ten years were investigated, including carbon fluxes and environmental variables such as temperature, precipitation, shortwave radiation, and vapor pressure deficit. By calculating the Spearman correlation coefficient, there was a congruence between photosynthetic productivity (i.e., gross primary productivity, GPP) and carbon sequestration (i.e., net ecosystem productivity, NEP) at thirteen forest sites, and at one forest site, GPP and NEP were decoupled. Annual GPP and NEP displayed a consistent trend when temperature and precipitation had significantly opposite trends and when temperature had a significantly positive correlation with VPD. But when VPD was significantly negatively correlated with both temperature and SW in spring and when temperature was negatively correlated with both SW and VPD in summer, a decoupling of GPP and NEP occurred. The impacts of various environmental factors on the annual carbon fluxes were calculated for each year and season using the path analysis method. At forest sites with consistent trends in GPP and NEP, annual, spring, and summer temperatures had significant positive correlations with GPP and ecosystem respiration (RE). While at the decoupled forest site, environmental factors had a stronger effect on RE, which then contributed to the observed decoupling of GPP and NEP. Finally, the Partial Least Squares method was used to analyze the relative contribution of each environmental factor to annual carbon fluxes. The results revealed that temperature and summer precipitation were the key environmental factors affecting forest ecosystems. This study provides important insights into the different responses of carbon fluxes in forest ecosystems undergoing environmental changes. [ABSTRACT FROM AUTHOR]

Abstract Wildfires, as an environmental filter, are pivotal ecological disturbances that reshape plant communities and soil dynamics, playing a crucial role in regulating biogeographic patterns and ecosystem services. In this study, we aim to explore the effects of wildfires on forest ecosystems, specifically focusing on the plant-soil feedback mechanisms within the northeastern margin of the Qinghai-Tibet Plateau (QTP). Utilizing Partial Least Squares Path Modeling (PLS-PM), we investigated the interrelationships among soil physicochemical properties, enzyme activities, species diversity, and community stability at varying post-fire recovery stages (5, 15, and 23 years). Results indicated that in the early recovery stages, rapid changes in soil properties such as decreased pH (p

The influence of lignite mining on vegetation constitutes a key issue due to the role of plants in restoring and maintaining the ecological balance of ecosystems. In this context, the identification of its impact on the functioning of silver birch (Betula pendula Roth) as a species often colonizing disturbed habitats takes on particular importance. Therefore, we aimed to determine the changes in nutrient content in silver birch overgrowing a spoil heap and in the vicinity of a fly ash settling pond and power plant. For this purpose, plant tissues (fine and coarse roots, stemwood, bark, coarse and fine branches, leaves) and soil samples (0–10, 10–20, 20–40, 20–40 cm deep) were examined. The basic soil characteristics were determined, along with the N, P, K, Ca, Mg, S, Fe, Mn, Cu, and Zn contents of the soil and plant samples. The soils varied in terms of soil pH and were poor in total organic carbon and other elements. The plant nutrient content varied strongly across the analyzed tissues, with the leaves usually containing the most and the stemwood the least nutrients. Statistical analysis indicated significant differences between the control vs spoil heap (particularly in Mn, S, and Mg) and the stand close to the settling pond (particularly in Ca, Mn, P, K, and S). We found that the chemical properties of the spoil heap and fly ash originating from the lignite mining operations are likely factors influencing nutrient accumulation in silver birch trees. [ABSTRACT FROM AUTHOR]

Through photosynthesis, forests absorb annually large amounts of atmospheric CO2. However, they also release CO2 back through respiration. These two, opposite in sign, large fluxes determine how much of the carbon is stored or released back into the atmosphere. The mean seasonal cycle (MSC) is an interesting metric that associates phenology and carbon (C) partitioning/allocation analysis within forest stands. Here, we applied the 3D-CMCC-FEM model and analyzed its capability to represent the main C-fluxes, by validating the model against observed data, questioning if the sink/source mean seasonality is influenced under two scenarios of climate change, in five contrasting European forest sites. We found the model has, under current climate conditions, robust predictive abilities in estimating NEE. Model results also predict a consistent reduction in the forest's capabilities to act as a C-sink under climate change and stand-aging at all sites. Such a reduction is predicted despite the number of annual days as a C-sink in evergreen forests increasing over the years, indicating a consistent downward trend. Similarly, deciduous forests, despite maintaining a relatively stable number of C-sink days throughout the year and over the century, show a reduction in their overall annual C-sink capacity. Overall, both types of forests at all sites show a consistent reduction in their future mitigating potential. [ABSTRACT FROM AUTHOR]

Forest ecosystems within national parks are threatened by various biotic and abiotic factors. To determine the causes of the desiccation and death of trees in mixed coniferous and deciduous forests of Tara National Park (TNP), Serbia, we monitored defoliation and mortality of individual trees in permanent experimental plots. Data on the desiccation of a large number of trees were gathered by determining the total volume of dry trees and areas of forests under drying stress. The two sets of data were combined to determine the impact of climatic events, primarily drought periods, on the desiccation of forests. Combining data from the International Co-operative Program on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with TNP data helped relate forest desiccation to climate events. Key climate signals were identified by monitoring tree defoliation changes in two permanent experimental plots, and then assessed for their influence on tree desiccation in the entire national park. The standardized precipitation evapotranspiration index (SPEI) was used for a more detailed analysis of the drought period. Despite the lack of climate data for a certain period, the SPEI index revealed a link between climate variables and the defoliation and desiccation of forests. Furthermore, the desiccation of trees was preceded by a long drought period. Although mixed coniferous-deciduous forests are often considered less vulnerable to natural influences, this study suggests that forest ecosystems can become vulnerable regardless of tree species composition due to multi-year droughts. These findings contribute to a better understanding of important clues for predicting possible future desiccation of forests. Continuous monitoring of the state of forests and of more permanent experimental plots in national parks could provide better quality data and timely responses to stressful situations. [ABSTRACT FROM AUTHOR]

Wildfires, as an environmental filter, are pivotal ecological disturbances that reshape plant communities and soil dynamics, playing a crucial role in regulating biogeographic patterns and ecosystem services. In this study, we aim to explore the effects of wildfires on forest ecosystems, specifically focusing on the plant-soil feedback mechanisms within the northeastern margin of the Qinghai-Tibet Plateau (QTP). Utilizing Partial Least Squares Path Modeling (PLS-PM), we investigated the interrelationships among soil physicochemical properties, enzyme activities, species diversity, and community stability at varying post-fire recovery stages (5, 15, and 23 years). Results indicated that in the early recovery stages, rapid changes in soil properties such as decreased pH (p < 0.001) and increased nutrient availability facilitate the emergence of early successional species with high resource utilization traits. As the ecosystem evolved toward a climax community, the soil and vegetation exhibit increased stability. Furthermore, soil enzyme activities displayed dynamic patterns that corresponded with changes in soil nutrient content, directly influencing the regeneration and diversity of plant communities. Importantly, our study documented a transition in the influence of soil properties on community stability from direct positive effects in initial recovery phases to negative impacts in later stages, while indirect benefits accrue through increased species diversity and enzyme activity. Vegetation composition and structure changed dynamically with recovery time during community succession. Plant nutrient absorption and accumulation affected nutrient dynamics in the soil, influencing plant regeneration, distribution, and diversity. Our results underscore the complex interactions between soil and vegetation that drive the recovery dynamics post-wildfire, highlighting the resilience of forest ecosystems to fire disturbances. This study contributes to the understanding of post-fire recovery processes and offers valuable insights for the management and restoration of fire-affected forest ecosystems. [ABSTRACT FROM AUTHOR]

Tree-related microhabitats (TreMs) describe the microhabitats that a tree can provide for a multitude of other taxonomic groups and have been proposed as an important indicator for forest biodiversity. So far, the focus of TreM studies has been on temperate forests, although the tropics provide a large forest area, with different types of forest and a high diversity of tree species, some of them with exceptionally high numbers of TreMs. In this study, TreMs in the lowland tropical forests of the Chocó (Ecuador) and in the mountain tropical forests of Mount Kilimanjaro (Tanzania) were surveyed. Our results extend the existing typology of TreMs of Larrieu et al. (2018) to include tropical forests and enabled a comparison of the relative recordings and diversity of TreMs between tropical and temperate forests. A new TreM form, Root formations, and three new TreM groups, concavities build by fruits or leaves, dendrotelms, and root formations, were established. In total, 15 new TreM types in five different TreM groups were specified. The relative recordings of most TreMs were similar between tropical and temperate forests. However, ivy and lianas, and ferns were more common in the lowland rainforest than in temperate forests, and bark microsoil, limb breakage, and foliose and fruticose lichens in tropical montane forest than in lowland rainforest. Mountain tropical forests hosted the highest diversity for common and dominant TreM types, and lowland tropical forest the highest diversity for rare TreMs. Our extended typology of tree-related microhabitats can support studies of forest-dwelling biodiversity in tropical forests. Specifically, given the ongoing threat to tropical forests, TreMs can serve as an additional tool allowing rapid assessments of biodiversity in these hyperdiverse ecosystems.

The prospect of Russia’s economic development will be inextricably bound up with the country’s success in the implementation of global climate initiatives. The strategy for the development of the national economy with a low level of greenhouse gas emissions, which is currently being formed, implies the fullest use of the potential for carbon sequestration by forest ecosystems, including through the implementation of various forest-climatic projects.The article shows that despite the world’s largest forest areas, the carbon-absorbing capacity of Russian forests cannot balance anthropogenic greenhouse gas emissions. Using the examples of several regions of the Volga region and Siberia, the spatial dynamics of the forest carbon budget in the 2010s is considered. For the regions of Siberia rich in boreal forests, there is a significant disproportion between the quantitative and qualitative characteristics of forest resources and the absorbing capacity, which is explained by the ineffective forestry regime in the territory and the high intensity of forest disturbances. Taking into account the fact that building an effective system for combating forest fires and insect pests requires very voluminous and expensive measures, the effectiveness of which is difficult to assess, the above illustrations of the current situation lead to the idea that, in addition to using the potential for increasing carbon sequestration in traditional forest regions in the implementation of forest-climatic projects should pay attention to sparsely forested areas.

Abstract Key message The forest canopy gaps, formed by natural or anthropogenic factors, have been found to reduce soil carbon content and increase nutrient availability. The magnitudes of these effects have been observed to increase with gap age and size, and are largely influenced by changes in temperature, precipitation, and solar radiation. Context Local studies have illustrated the influence of canopy gaps on the spatial heterogeneity of soil carbon and nutrients, playing a pivotal role in driving forest regeneration and succession. Nevertheless, it remains largely unknown whether the response of soil carbon and nutrient content to gap formation is consistent across forest ecosystems at global scale. Aims The aim of this paper is to assess the homogeneity of the observed responses of soil carbon and nutrients following gap formation among a wide array of forest ecosystems and climatic regions. Methods We performed a meta-analysis synthesizing 2127 pairwise observations from 52 published articles to quantify the changes in in soil physical, chemical, and microbial variables resulting from gap creation in natural forests and plantations spanning tropical to boreal regions. Results Canopy gaps resulted in significant decrease of soil organic carbon (C org) and microbial carbon (C mic). The concentrations of ammonium (NH4 +), nitrate (NO3 −), and available phosphorus (available P) increased following gap creation. These changes mainly occurred in the growing season and in the mineral soil layer, becoming more pronounced with increasing gap age and size. The change in C org was negatively regulated by mean annual precipitation, and was associated with the changes in Nt and N mic . The change in NH4 + was positively regulated by mean annual temperature, and was associated with the changes in available P and oxidoreductases (Ox-EEAs). The model explaining the change in soil carbon content exhibited a higher explanatory power than the one accounting for changes in soil nutrient availability. Conclusion The results indicated that forest canopy gaps resulted in a reduction in soil carbon content and an increase in nutrient availability. These findings contribute to a better understanding of the role of small-scale disturbances as drivers of forest ecosystem succession.

The program provisions on the geosystem monitoring of forests in connection with modern climate changes put forward earlier by the author are being developed. The search strategy is presented in the form of an experimental geoecological analysis (using the example of the forest ecosystems of the Volga River basin), with the implementation of the complete monitoring triad "state–forecast–management," according to the Israel–Gerasimov concept. The theoretical and scientific-methodical foundations of geosystem monitoring are considered, and the methods of basic and predictive empirical-statistical modeling of the functional and structural characteristics of forest communities developed by the author are presented. An integrated landscape-ecological approach to monitoring is presented by the analysis and forecast of climate-genic changes in three groups of invariant indicators of the structural and functional organization of forest biogeosystems: (1) numerical parameters characterizing the tightness of intercomponent links (as an indicator of the territorial integrity of the geo(eco)system); (2) primary bioproductivity as the main indicator of the biological cycle; (3) index of labile (phytocoenotic) stability of geo(eco)systems as integral indicators of their ecological reserve. A working algorithm for geosystem monitoring of forests is described, which describes a successive change in the stages of observation, forecasting, and regulation, with the identification of mitigation and adaptation effects on the carbon balances of forest ecosystems. [ABSTRACT FROM AUTHOR]

Based on our own field data and using modeling of modern potential ranges (in the MaxEnt program), an assessment of the spatial distribution of the rare representative of the longhorn beetle family, Callipogon (Eoxenus) relictus Semenov 1899, was conducted in northeast Asia (220 geographic locations). The generated maps of the potential range of C. relictus demonstrate a high likelihood of the species' presence in the upland areas of southern far east Russia, the provinces of northeastern China, and the Korean Peninsula. Field data also indicate the extensive association of the species with undisturbed broadleaf and coniferous–broadleaf forests in northeast Asia. Maps of the potential distribution of C. relictus in northeast Asia have been compiled based on four climate change scenarios from the present time to 2070. Under all of the climate scenarios used, it is shown that suitable habitats for the species will persist in certain areas of Primorsky Krai, as well as neighboring provinces of the People's Republic of China and a small enclave on the Korean Peninsula in Gangwon-do province. Significant reduction in suitable conditions for the rare longhorn beetle will occur in the rest of its distribution range. [ABSTRACT FROM AUTHOR]

Floodplain forests are among the most threatened ecosystems in Europe, providing specific conditions for many species. The research in floodplain forests in conditions agrarian landscape and in the Dunajské Luhy Protected Landscape Area (important European territory) was conducted. During the years 2020–2022, 2827 individuals of beetles belonging to 93 species at 6 locations representing two types of habitats (willow–poplar floodplain forest, regenerated poplar forest) were recorded. The beetles were collected using the pitfall traps method. Through spatial modeling (redundancy analysis—RDA), we found a strong preference of species for floodplain forests located in the Dunajská Luhy Protected Landscape Area a European important territory, where there was also a predominance of adaptable and relict species. These species prefer a more stable environment and undisturbed ecosystems with a sufficient food optimum. On the contrary, number of species belonging to the eurytopic group correlated with the conditions of the agrarian landscape were recorded. Moreover, these species inhabit ecosystems disturbed by anthropic activity. We also confirmed a significant difference in the number of individuals and species between the use of the landscape (agrarian landscape, Dunajské Luhy). We confirmed a larger number of individuals and species in the Dunajské Luhy PLA (important European territory). Our results bring new information about the negative impact of the agroeciosystem on floodplain forests. In order to preserve the European important floodplain forests in the Dunajské Luhy Protected Landscape Area, it is necessary to know the ecological niches between beetles and ecosystems. [ABSTRACT FROM AUTHOR]

Key message: The forest canopy gaps, formed by natural or anthropogenic factors, have been found to reduce soil carbon content and increase nutrient availability. The magnitudes of these effects have been observed to increase with gap age and size, and are largely influenced by changes in temperature, precipitation, and solar radiation. Context: Local studies have illustrated the influence of canopy gaps on the spatial heterogeneity of soil carbon and nutrients, playing a pivotal role in driving forest regeneration and succession. Nevertheless, it remains largely unknown whether the response of soil carbon and nutrient content to gap formation is consistent across forest ecosystems at global scale. Aims: The aim of this paper is to assess the homogeneity of the observed responses of soil carbon and nutrients following gap formation among a wide array of forest ecosystems and climatic regions. Methods: We performed a meta-analysis synthesizing 2127 pairwise observations from 52 published articles to quantify the changes in in soil physical, chemical, and microbial variables resulting from gap creation in natural forests and plantations spanning tropical to boreal regions. Results: Canopy gaps resulted in significant decrease of soil organic carbon (Corg) and microbial carbon (Cmic). The concentrations of ammonium (NH4+), nitrate (NO3−), and available phosphorus (available P) increased following gap creation. These changes mainly occurred in the growing season and in the mineral soil layer, becoming more pronounced with increasing gap age and size. The change in Corg was negatively regulated by mean annual precipitation, and was associated with the changes in Nt and Nmic. The change in NH4+ was positively regulated by mean annual temperature, and was associated with the changes in available P and oxidoreductases (Ox-EEAs). The model explaining the change in soil carbon content exhibited a higher explanatory power than the one accounting for changes in soil nutrient availability. Conclusion: The results indicated that forest canopy gaps resulted in a reduction in soil carbon content and an increase in nutrient availability. These findings contribute to a better understanding of the role of small-scale disturbances as drivers of forest ecosystem succession. [ABSTRACT FROM AUTHOR]

Mountain pine beetles (MPBs) pose a substantial threat to North American pine forests, causing extensive tree mortality over large areas. Their tree‐killing ability is closely linked to mass aggregation on host trees triggered via pheromones and dependence on their symbiotic fungi. However, the influence of a changing climate on the biology of MPBs and their co‐evolved interactions with their fungal symbionts remains uncertain. To investigate this, male and female pairs of beetles were introduced into freshly cut logs from lodgepole pine trees and placed in controlled climate chambers with manipulated environmental conditions, including two levels of CO2 (ambient vs. 1000 ppm), O3 (ambient vs. 100 ppb) and humidity (33% vs. 65%). The beetle‐infested logs were left in these chambers for 1 month and then returned to ambient conditions until brood emergence. Emerging broods were collected for further analysis. Additionally, three species of fungal symbionts (Grosmannia clavigera, Ophiostoma montium and Leptographium longiclavatum) were subjected to the same CO2, O3 and humidity conditions for 5 days. Lower humidity promoted MPB reproduction and fungal growth. Elevated CO2 accelerated larval growth and emergence while improving brood pheromone production. Elevated O3 had a negative impact on MPB reproduction and brood fitness while improving its immune responses to an entomopathogenic fungus (Beauveria bassiana). It also inhibited fungal growth and reproduction, whereas elevated CO2 had varied (positive or negative) effects on fungal growth and ergosterol (proxy to fungal mass) production depending on the fungal species. Together, these findings suggest that climate change can potentially alter the interactions between MPBs and their fungal symbionts, highlighting the importance of understanding how climate change affects forest pests and their symbiotic relationships to develop effective management strategies in the future. [ABSTRACT FROM AUTHOR]

Forest fire frequency, extent, and severity have rapidly increased in recent decades across the western United States (US) due to climate change and suppression‐oriented wildfire management. Fuels reduction treatments are an increasingly popular management tool, as evidenced by California's plan to treat 1 million acres annually by 2050. However, the aggregate efficacy of fuels treatments in dry forests at regional and multi‐decadal scales is unknown. We develop a novel fuels treatment module within a coupled dynamic vegetation and fire model to study the effects of dead biomass removal from forests in the Sierra Nevada region of California. We ask how annual treatment extent, stand‐level treatment intensiveness, and spatial treatment placement alter fire severity and live carbon loss. We find that a ∼30% reduction in stand‐replacing fire was achieved under our baseline treatment scenario of 1,000 km2 year−1 after a 100‐year treatment period. Prioritizing the most fuel‐heavy stands based on precise fuel distributions yielded cumulative reductions in pyrogenic stand‐replacement of up to 50%. Both removing constraints on treatment location due to remoteness, topography, and management jurisdiction and prioritizing the most fuel‐heavy stands yielded the highest stand‐replacement rate reduction of ∼90%. Even treatments that succeeded in lowering aggregate fire severity often took multiple decades to yield measurable effects, and avoided live carbon loss remained negligible across scenarios. Our results suggest that strategically placed fuels treatments are a promising tool for controlling forest fire severity at regional, multi‐decadal scales, but may be less effective for mitigating live carbon losses. Plain Language Summary: California has seen a marked increase in forest fire activity in recent decades. This trend is expected to continue with climate change, endangering lives and altering ecosystems. Fuels reduction treatments, including controlled burning and mechanical removal of woody debris from fire‐prone forests, have received increasing policy attention in recent years as a wildfire mitigation strategy. However, the impacts of regional‐scale, multi‐decadal fuels reduction programs are not well understood. We use a coupled dynamic vegetation and fire model to compare the impacts of different fuels treatment strategies to understand how intersecting technical and political constraints impact treatment efficacy over 100 years of treatments. We find that precise assignment of treatments to the most fuel‐heavy stands in the region could decrease cumulative avoided fire‐driven stand‐replacement rates by ∼50% compared with no‐treatment simulations, and by ∼30% when prioritization of fuel loading was lower. Opening remote, rugged, and multi‐stakeholder lands for treatment in tandem with high prioritization of fuel loading could increase total avoided stand mortality events to ∼90%. Overall, avoided live carbon loss rates are less sensitive to treatment, and remained relatively small in absolute terms. Importantly, we found that even effective treatments may take multiple decades to yield measurable results on a regional scale. Key Points: Fuels treatments are increasingly legislated as a mitigation tool to adapt to the changing wildfire regime in the western United StatesFuels reduction programs that identify high risk forests decrease fire severity, but treatment effects only emerge after several decadesPrioritizing treatments of fuel‐heavy stands minimizes the time to significant treatment effects and maximizes fire severity reductions [ABSTRACT FROM AUTHOR]

Allometric equations are often applied to estimate volume and carbon stocks of forest ecosystems. This study focused on formulating or developing allometric equations or models for estimating the volume of standing Toona ciliata M. Roem. trees in the red cedar woodlands of Northwestern Himalayas of India. Despite rich floral diversity, there has been a scarcity of such equations for this region. The research involved sampling and measuring 100 red cedar trees across four sites. Dendrometric variables were then measured for each site to create model s based on height, diameter at breast height (DBH), and form factor as predictor variables. This work underscores the importance of allometric equations in accurately assessing the volume of red cedar woodlands, as they consider factors like vegetation type, management practices, and environmental conditions. The findings will enhance our grasp of allometric equations and contribute to the development of tools for forest planners, farmers, and researchers, enabling precise prediction of forest resources in terms of volume. This will, in turn, support effective management strategies for red cedar woodlands in the Northwestern Himalayas and similar ecosystems worldwide. [ABSTRACT FROM AUTHOR]

Tree cores are a highly valuable scientific resource. Annual growth ring data can, for example, improve our understanding of climate change impacts and effects of environmental pollution, allow for better annual estimations of tree growth patterns and carbon storage, and help quantify dynamics and changes in forest ecosystems. The value of coring trees for research has been weighted against concerns around the potential harm coring might cause to trees. To date, there is indeed limited research accurately quantifying the potential effects of coring on tree growth and only a handful of studies assessing its influence on mortality. Consequently, many European long-term forest inventorying and monitoring programs are concerned that tree coring might bias the repeated tree measurements in permanent plots, which they rely on for assessments of states and changes of forests. In this study, we assessed the effects of tree coring on the growth and mortality of three widespread European tree species approximately 10 years after they were cored. We used repeated tree measurements from permanent research sites in Switzerland and Ukraine. In Switzerland, we assessed 35 cored and 159 uncored Norway spruce (Picea abies) trees as well as 147 cored and 332 uncored silver fir (Abies alba) trees. In Ukraine, we assessed 348 cored and 6′611 uncored European beech (Fagus sylvatica) trees. We found no statistical evidence that coring negatively affected the growth or mortality of the three tree species assessed. Although we cannot rule out subtle effects on tree health and wood quality, our findings do not provide any evidence that coring affects or biases repeated measurements (such as DBH measures and recording of mortality) performed on the investigated tree species. Tree coring could therefore be considered more often for routine incorporation, particularly in long-term forest inventorying and monitoring programs and initiatives. [ABSTRACT FROM AUTHOR]

One of the challenges faced by current forestry practice is how to effectively respond to the great environmental and global changes to achieve biodiversity conservation and the demands for timber and other non-wood forest products. Worldwide forestry suggests that the approach of ecological silviculture can provide efficient tools for facing these challenges. The applied forest land management during the last seven decades in Greece relies on the principles of sustainability set by ecological silviculture through time. Greek silviculturists adopted these principles many years ago by setting the following priorities and perspectives for applied Greek forestry: the protection of all Greek forests, the systematic rehabilitation of degraded forests (e.g., conversion of coppices to high forest), the promotion of tree species mixture, the improvement of the horizontal and vertical structure of all forest ecosystems, the exclusive use of species natural regeneration, the application of selective felling prohibiting any of clear-cutting, the extensive use of low impact harvesting practices, the retention of a small number of old trees for promoting biodiversity, the protection of all rare and endangered flora and fauna species, and establishment forest protected areas. In this study, three modern indicators were used to evaluate the results of the above silvicultural ecological approach to Greek forests after a period of seven years of forestry practice based on these principles.