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Present and future climatic trends are expected to markedly alter water fluxes and stores in the hydrologic cycle. In addition, water demand continues to grow due to increased human use and a growing population. Sustainably managing water resources requires a thorough understanding of water storage and flow in natural, agricultural, and urban ecosystems. Measurements of stable isotopes of water (hydrogen and oxygen) in the water cycle (atmosphere, soils, plants, surface water, and groundwater) can provide information on the transport pathways, sourcing, dynamics, ages, and storage pools of water that is difficult to obtain with other techniques. However, the potential of these techniques for practical questions has not been fully exploited yet. Here, we outline the benefits and limitations of potential applications of stable isotope methods useful to water managers, farmers, and other stakeholders. We also describe several case studies demonstrating how stable isotopes of water can support water management decision-making. Finally, we propose a workflow that guides users through a sequence of decisions required to apply stable isotope methods to examples of water management issues. We call for ongoing dialogue and a stronger connection between water management stakeholders and water stable isotope practitioners to identify the most pressing issues and develop best-practice guidelines to apply these techniques.

Climate change is the most severe ecological challenge faced by the world today. Forests, the dominant component of terrestrial ecosystems, play a critical role in mitigating climate change due to their powerful carbon sequestration capabilities. Meanwhile, climate change has also become a major factor affecting the sustainable management of forest ecosystems. Climate-Smart Forestry (CSF) is an emerging concept in sustainable forest management. By utilizing advanced technologies, such as information technology and artificial intelligence, CSF aims to develop innovative and proactive forest management methods and decision-making systems to address the challenges of climate change. CSF aims to enhance forest ecosystem resilience (i.e., maintain a condition where, even when the state of the ecosystem changes, the ecosystem functions do not deteriorate) through climate change adaptation, improve the mitigation capabilities of forest ecosystems to climate change, maintain high, stable, and sustainable forest productivity and ecosystem services, and ultimately achieve harmonious development between humans and nature. This concept paper: (1) discusses the emergence and development of CSF, which integrates Ecological Forestry, Carbon Forestry, and Smart Forestry, and proposes the concept of CSF; (2) analyzes the goals of CSF in improving forest ecosystem stability, enhancing forest ecosystem carbon sequestration capacity, and advocating the application and development of new technologies in CSF, including artificial intelligence, robotics, Light Detection and Ranging, and forest digital twin; (3) presents the latest practices of CSF based on prior research on forest structure and function using new generation information technologies at Qingyuan Forest, China. From these practices and reflections, we suggested the development direction of CSF, including the key research topics and technological advancement. [ABSTRACT FROM AUTHOR]

Timber‐oriented forest management profoundly alters forest structure and composition, with complex effects on associated biodiversity. However, while species' responses to forest management and resulting structural characteristics have been the subject of numerous studies, direct and indirect effects that cascade through trophic levels are rarely disentangled. As insectivorous bats are particularly sensitive to changes in forest structure, that shape their available flight space, we investigated how forest structure, composition and management also indirectly modify their habitats, for example, by affecting important insect prey groups. We used structural equation models (SEMs) to test bat responses to forest composition, structure (forest heterogeneity, old‐growth attributes) and management intensity, quantifying direct and indirect prey‐mediated effects. For that, three bat guilds—short‐ (SRE), mid‐ (MRE) and long‐range echolocating (LRE) bats—and their prey insects (moths and ground beetles) were analysed from 64 sites in the Black Forest, Germany. We found guild‐specific effects on bats: While the structural heterogeneity of forests directly influenced the activity of bat guilds, the main influence of forest management, composition and structure was mediated through their prey‐groups. SRE activity responded to moths and LRE activity was associated with ground beetles, with positive effects of the insect groups' abundance, but negative effects of the same group's species richness. In addition, the SEM approach revealed a negative top‐down relationship between MRE activities and moths, suggesting predation or avoidance behaviour of moths. While forest management directly or indirectly increased prey insect abundance, it negatively affected the availability of roosting structures for bats. Synthesis and applications. The results highlight the indirect and positive effects of forest management on bats and support the important role of bats in insect regulation within continuous cover forests. Although forest management created small gaps that improved foraging habitats for most bats, it compromised the roosting functionality for bats. The ‘close‐to‐nature forestry’ currently prevalent in Europe mainly promotes continuous‐cover forests in mid‐successional stages. Expanding the forest management portfolio towards open and old‐growth forests would increase roosting opportunities and provide complementary foraging habitats for different bat species, while promoting high biodiversity in managed forest landscapes. [ABSTRACT FROM AUTHOR]

Recent and projected changes in climate over this century pose an unprecedented threat to the health, diversity, and productivity of forest ecosystems. Forests have migrated and adapted to long-term changes in climate over thousands to millions of years; however, natural migration rates and adaptive responses of tree populations cannot match the rapid pace of current climate change. Consequently, more climate-informed approaches to reforestation are needed as current reforestation strategies using local seed sources may no longer be adequate to meet forest management objectives. Assisted migration is a climate change adaptation technique that can help maintain the ecosystem services and economic value that forests provide. Forestry assisted migration (FAM) focusses on the movement of populations of widespread, commercially, or ecologically important forest tree species within or just beyond their current ranges as a way to maintain forest productivity and health in the face of climate change. Although the forestry community recognizes FAM as a reforestation tool, guidance for planning and implementation of FAM is lacking and a framework that provides this guidance can prove useful to land managers with limited time and resources available who want to undertake FAM. We developed a practical framework (the FAM Framework) to provide a structured approach to ensure the most important considerations and best available science are utilized by land managers wanting to implement FAM on their land base. The FAM Framework incorporates multiple factors for the application of FAM in four sequential phases: assessment and analysis, climate-based plant material selection, seed procurement and deployment, and documentation and monitoring. The FAM Framework was tested by developing an assisted migration plan for the Superior National Forest, Minnesota (MN), and lessons learned from the development of this specific plan were used to revise and improve the FAM Framework for suitability across all lands. While originally designed to meet the needs of National Forest System land managers, it is relevant and applicable across the spectrum of land ownership because it incorporates consideration of critical elements in planning and implementing FAM on any landscape while facilitating adaptive management for active learning and future implementation. [ABSTRACT FROM AUTHOR]

Most canopy insect research takes place in tropical forests, where communities are highly vertically stratified. However, temperate forest canopies also provide critical resources to many species and are under intense pressure from global change drivers. The relative lack of knowledge regarding temperate canopy insect ecology impedes our forest management and conservation decisions such that we may be losing temperate canopy biodiversity before we know it exists. We directly compared ant diversity and community composition on the ground and in the tree canopy of North American temperate deciduous forests for the first time. We also evaluated two canopy sampling methods—baits and hand collections. We collected 34 ant species from 102 trees across seven sites. Ant diversity was greater on the ground than in the canopy, and species turnover created distinct communities across vertical strata. Only 12% of species were exclusively arboreal, but 47% were collected in both strata, indicating the canopy is an important resource for temperate ants, even if they are not restricted there. Baiting and hand‐collecting recovered similar species richness, but whether baits captured a subset of hand‐collected species or a unique assemblage was site‐dependent. Nevertheless, we suggest that these methods are most effective in conjunction. Hand collection allowed us to document arboreal nests of 10 species, including the invasive needle ant, Brachyponera chinensis, which was previously thought to be strictly terrestrial. Our results emphasise the importance of including the canopy in temperate forest ecology and conservation assessments. [ABSTRACT FROM AUTHOR]

ABSTRACT Incentives are a widely used tool for addressing deforestation and are often implemented as collective contracts. Local institutions are crucial to the solution of collective action problems associated with forest conservation, but we still have little knowledge of how to encourage institutional creation through policy. Since collective contracts do not eliminate freeriding incentives, we argue that their success hinges on their ability to stimulate the creation of institutions for collective action. To test these ideas, we analyze data from an incentivized lab‐in‐the‐field experimental collective action game played with natural resource users in four developing countries. The experiment simulates management of a common forest, and groups were randomly assigned to a conservation incentive payment condition. We observe how much group members attempt to coordinate on the creation of institutional rules and find experimental evidence that an external incentive program can stimulate the endogenous creation of informal institutions. [ABSTRACT FROM AUTHOR]

Long‐distance acoustic signals mediate important social interactions between animals, and the structure of the environment can influence sound transmission to affect communication distance. Anthropogenic disturbances such as fire suppression alter forest structure and can potentially affect acoustic interactions by altering sound attenuation patterns. In the spruce‐fir and mixed‐conifer forests of the Pinaleño Mountains, Arizona, USA, that harbor endangered Mount Graham red squirrels (Tamiasciurus fremonti grahamensis), numerous historical anthropogenic disturbances have altered forest characteristics and contributed to habitat degradation and loss. In this study, we assessed how recent forest management treatments influenced the attenuation of red squirrel territorial rattle vocalizations. In June 2023–August 2023, we broadcast and recorded rattles 5.4 m above the forest floor at various distances (1, 10, 20, and 40 m) to mimic hypothetical senders and receivers. We used on‐the‐ground measurements and lidar to quantify forest structure relative to patterns of sound attenuation in 3 treatments: thinning, understory fuel reduction, and untreated control plots. Across all treatments, we found that increasing tree basal area resulted in higher attenuation, with rattles being approximately 6 dB lower in amplitude in the most dense compared to the least dense plots, equivalent to a doubling in squirrel communication distance. Additionally, rattles on untreated control plots experienced more attenuation than thinned (~3 dB) and fuel‐reduced (~1.5 dB) plots. A lidar‐derived measure of canopy structure was a better predictor of rattle attenuation than lower resolution on‐the‐ground measurements. In the short‐term, forest thinning may facilitate development of acoustic social neighborhoods that increase squirrel fitness, though alternative costs of more open forests exist. More generally, our results indicate that forest management can affect the efficacy of acoustic communication and that integration of signaling and sensory ecology with remote sensing can inform wildlife conservation. [ABSTRACT FROM AUTHOR]

Aims: This study examines the effects of land-use types and slope position on selected soil physico-chemical properties in the Ageza Watershed, Northwestern Ethiopia, focusing on soil fertility depletion and its impact on agricultural productivity. Materials and methods: The experiment utilized a randomized complete block design (RCBD) with three replications, involving three land-use types and slope positions. A total of 27 soil samples (both disturbed and undisturbed) were collected, prepared, and analyzed for selected physico-chemical properties following standard laboratory procedures. Data were analyzed using two-way ANOVA with SAS software. Results: Significant variations in most soil physico-chemical properties were observed across land-use types and slope positions. Soil bulk density, organic carbon (OC), total nitrogen (TN), available phosphorus (Av. P), cation exchange capacity (CEC), and exchangeable bases significantly (P ≤ 0.001) differed among the land-use types and slope positions. The main effects showed significant (P ≤ 0.05) differences in sand, silt, and clay contents across the land-use types. However, pH did not show significant differences (P > 0.05). Soil bulk density, silt content, Av. P, exchangeable bases, and CEC all showed significant (P ≤ 0.01) differences among the slope positions. Forest land had the highest values for clay (46.11%), OC (6.08%), Av. P (20.60 mg/kg), CEC (33.89 cmol (+) kg-¹), and exchangeable cations: Ca²+ (23.72 cmol (+) kg-¹), Mg²+ (4.40 cmol (+) kg-¹), K+ (1.18 cmol (+) kg-¹), and Na+ (0.77 cmol (+) kg-¹). Grazing land exhibited higher silt and bulk density, while cultivated land had higher sand content. Lower slope positions recorded the highest values for clay (47.33%), silt (20.77%), pH (4.90), Av. P (16.61 mg/kg), Ca²+ (20.10 cmol (+) kg-¹), Mg²+ (3.73 cmol (+) kg-¹), K+ (1.00 cmol (+) kg-¹), Na+ (0.66 cmol (+) kg-¹), and CEC (28.71 cmol (+) kg-¹), while bulk density was higher in the upper slope position. Conclusion: Land-use types and slope positions significantly influence variations in soil physico-chemical properties and overall soil fertility status. Forest preservation and management are essential to improve the soil fertility in this region. [ABSTRACT FROM AUTHOR]

Background: In Lyme-endemic areas, limited research has investigated the risk of tick-borne diseases among frontline workers in fire management. This study aimed to compare the exposure histories to ticks and tick-borne pathogens, knowledge, and prevention practices between individuals engaged in fire-related forest management and those participating in recreational activities within Santa Cruz County, CA, in an area of high risk of tick exposure. Methods: Blood samples from 55 forest workers and 58 members of the public were tested for bacterial DNA of and antibodies to Borrelia burgdorferi, Anaplasma phagocytophilum, and Rickettsia species. In addition, a questionnaire was administered to 54 workers and 84 members of the public to identify gaps in knowledge and prevention practices. Results: Although workers had a higher percentage of positive B. burgdorferi antibodies than the public (5.5% compared with 1.7%), the difference was not statistically significant. Conversely, rickettsial antibodies were more prevalent among the public (17.2% versus 3.6% for workers), but specificity to pathogenic bacteria could not be confirmed. No DNA for the three pathogens or antibodies against A. phagocytophilum were detected. Many workers and members of the public reported tick bites (67.4% of participants), with a notable 11% increase among workers in the odds of being bitten for each additional year spent working in forests. Although workers took greater precautions, significant knowledge and practice gaps were identified among both populations, such as an inability to distinguish tick species from common arthropods (mites, spiders, fleas), overestimating the size of ticks, and inappropriate tick-removal techniques. Conclusion: This study underscores the risk of tick-borne diseases faced by fire management workers in Lyme disease–endemic regions. The findings emphasize the necessity for future studies of Lyme disease within this population, and highlight the urgent need for enhanced training programs to minimize these risks. [ABSTRACT FROM AUTHOR]

Floodplain forests are among the most endangered ecosystems worldwide, even though they are hotspots for numerous taxa. The abandonment of traditional management and large‐scale timber extraction, such as clear‐cutting, has led to a decline in floodplain forest biodiversity. Retention forestry has the potential to facilitate the implementation of an ecologically sustainable forest management approach. Despite the increasing popularity of this method, its potential for spider diversity conservation, especially its comparison with the widespread practice of clear‐cutting, is still poorly studied.We studied the short‐term effect of forestry treatments (dispersed retention with 60% retained trees and clear‐cutting) on the diversity of ground‐dwelling spiders in the floodplain forests along the Lower Morava (March) and Dyje (Thaya) rivers in the Czech Republic. Spiders were sampled using pitfall traps during 2021 (pre‐harvest year) and 2022 (post‐harvest year).A total of 10,005 specimens from 167 species were recorded. Both forestry treatments simplified habitat structure compared with pre‐harvest conditions, resulting in lower beta‐diversity within sites. However, dispersed retention had higher alpha‐ and beta‐diversity than clear‐cuts, indicating that retention provided a more complex‐structured habitat. Dispersed retention and clear‐cuts hosted distinct spider assemblages with characteristic indicator species. Species typical of open and significantly disturbed habitats preferred clear‐cuts, while species typical of forests and (semi‐) open habitats, including threatened species, showed a preference for dispersed retention.Our results demonstrated, for the first time, that dispersed retention forestry could serve as an effective management tool for conserving the ground‐dwelling assemblages of spiders in floodplain forests. [ABSTRACT FROM AUTHOR]

Climate change has significant natural and economic implications, but its extent is particularly challenging to assess in forest management, a field which combines both of the previous aspects and requires the evaluation of the impact of climate change on tree species over a 100-year timeframe. Oaks are among the tree species of significant natural and economic value in Europe. Therefore, the aim of this study was to analyze all oak stands in Poland and verify the hypothesis regarding differences between Quercus robur and Quercus petraea stands in terms of soil type, annual total precipitation, average annual air temperature, and the length of the growing season. Additionally, this study aimed to analyze the impact of these differences on the growth rates of both oak species and test whether climate change may affect oak stands. A database containing 195,241 tree stands, including different oak species with varying shares in the stand (from 10% to 100%), was analyzed. A particular emphasis was placed on Q. robur and Q. petraea. The results show that, although both oak species have a wide common range of occurrence, there are clear differences in their habitat preferences. Based on the ordinal regression analysis of selected oak stands, it was concluded that an increase in air temperature of 1 °C could impair the growth of Q. robur and slightly improve the growth of Q. petraea. This may indicate the possibility of expanding the geographic range of sessile oaks towards the east and northeast under warming climatic conditions, provided that appropriate moisture conditions are maintained. [ABSTRACT FROM AUTHOR]

Effective forest management necessitates spatially explicit information about tree species composition. This information supports the safeguarding of native species, sustainable timber harvesting practices, precise mapping of wildlife habitats, and identification of invasive species. Tree species identification and geo-location by machine learning classification of UAV aerial imagery offer an alternative to tedious ground surveys. However, the timing (season) of the aerial surveys, input variables considered for classification, and the model type affect the classification accuracy. This work evaluates how the seasons and input variables considered in the species classification model affect the accuracy of species classification in a temperate broadleaf and mixed forest. Among the considered models, a Random Forest (RF) classifier demonstrated the highest performance, attaining an overall accuracy of 83.98% and a kappa coefficient of 0.80. Simultaneously using input data from summer, winter, autumn, and spring seasons improved tree species classification accuracy by 14–18% from classifications made using only single-season input data. Models that included vegetation indices, image texture, and elevation data obtained the highest accuracy. These results strengthen the case for using multi-seasonal data for species classification in temperate broadleaf and mixed forests since seasonal differences in the characteristics of species (e.g., leaf color, canopy structure) improve the ability to discern species. [ABSTRACT FROM AUTHOR]

The results of the dynamic simulation of organic matter stocks in forest soils are discussed from the point of a predictive assessment of carbon sink depending on forest site types and forest management regimes. The biological cycle in the "soil–forest stand" system was simulated with FORRUS-S, Romul_Hum, and SCLISS simulation models. Computational experiments were carried out for three forest enterprises and a nature reserve located in the Republic of Karelia and in Nizhni Novgorod, Moscow, and Bryansk oblasts, which corresponds to a gradient of zonal conditions from the middle taiga to the broadleaved forest subzone. Forest survey data available for all study objects were used to simulate the long-term (100 years) forest dynamics. Calculations of soil Corg pools were carried out separately for each forest taxation area using the corresponding characteristics of the forest stand (mean height, diameter, basal area, growing stock) and soil (Corg and Ntot contents in the forest floor and mineral soil) as initial data, which made it possible to take into account the spatial variability of forest conditions and successional change of species in the resulting area-based estimates of soil carbon sink. Under the nature reserve regime, the mean increase in soil stock of organic matter by 35–80 t C/ha compared to the initial values is predicted for all territories over 100 years. Felling practices of varying intensity reduce the possible Corg sink into forest soils by an average of 30–50 t/ha compared to the reserve regime. Regional features of the dynamics of organic matter are manifested in different ratios of carbon accumulation in organic and organomineral soil horizons. [ABSTRACT FROM AUTHOR]

Via sheltering, decoupling and buffering mechanisms, tree canopies have the capacity to mitigate impacts of multiple global‐change drivers on below‐canopy processes and organisms in forests. As a result, canopies have an important potential as nature‐based solution.The optimal combinations of forest canopy structural attributes to jointly mitigate the impacts of multiple global‐change drivers on below‐canopy organisms and processes have received little attention to date.To help solving this research gap, here we review how forest canopies modulate the effects of four important global‐change drivers—climate warming, drought, air pollution and biological invasions—on below‐canopy conditions. Particular attention is paid to mitigating canopy attributes that can be influenced by forest management, including canopy cover, tree species composition and vertical and horizontal structure.Synthesis. We show that the potential of forest canopies to mitigate global‐change effects is highly context‐dependent and that optimal canopy‐based solutions strongly depend on the environmental context and the targeted subcanopy organisms. Hence, holistic approaches, which maximize synergies and minimize trade‐offs, are needed to optimize the solution potential of forest canopies. [ABSTRACT FROM AUTHOR]

In the temperate mixed oak forests of Central Europe, outbreaks of insects such as the spongy moth, Lymantria dispar, can cause severe defoliation and insecticide is sometimes applied for their control. Parasitoids, mainly Hymenoptera and Diptera, are among the most diverse and important natural enemies of caterpillars in these forests. However, due to their cryptic lifestyle and taxonomic difficulties, we lack knowledge on the impact of insecticide applications on complex host‐parasitoid networks.In a large‐scale field experiment, we tested the effect of spraying the lepidopteran‐specific insecticide Mimic (tebufenozide) on the abundance and community composition of both adult and larval parasitoids. We combined morphological identification, DNA barcoding and metabarcoding to identify parasitoids adult or inside caterpillars, both sampled by canopy fogging during an outbreak and two subsequent years. We analysed the abundance of parasitoids, community composition and network specialisation using statistical methods that account for sample incompleteness in host‐parasitoid data.For adult parasitoid assemblages, we found strong annual effects on abundance, with highest numbers of adult parasitoids occurring in the outbreak year, as well as on annual changes in community composition, but no effect linked to insecticide application. However, the abundance and species number of immature parasitoids revealed negative effects of insecticide application, while community composition was only affected by annual variation.Coverage‐based network analyses showed a reduction of taxonomic network diversity and network specialisation associated with insecticide application in the first 2 years.Synthesis and applications: This real‐world experiment shows that parasitoid populations respond immediately to large‐scale outbreaks but only limited to local disturbances. Results indicate that this group of natural enemies exhibits high mobility, enabling them to track host populations across large spatial scales. However, our observation of reduced network specialisation after insecticide application is a warning signal that ecosystem function, and consequently natural pest control services, may be impaired by human interference at the local stand scale. [ABSTRACT FROM AUTHOR]

Managing forests for timber yields reduces the amounts of old trees and deadwood, which has profound effects on species that are dependent on them. Retention forestry, where some trees are permanently left unharvested on clear‐cut sites, may enable the formation of deadwood and old trees in managed forests, but it is unresolved how well these practices facilitate the occurrence of species in managed forests, especially in the long term.We studied the capacity of tree retention practices to support the diversity of epiphytic lichens, a key group among threatened forest species. We compared lichen assemblages on retained trees in harvested sites to those on trees in unharvested control sites. The data were collected 21‐year post‐harvest and included living trees, snags (standing dead trees) and logs (fallen trees) of Pinus sylvestris (Scots pine).Living trees, snags and logs each hosted distinct lichen communities. The highest lichen diversity was found on snags.On living trees, species richness was similar in harvested and unharvested sites, but there was slight species turnover. In contrast, deadwood in unharvested sites hosted higher species richness and distinct species assemblages compared to deadwood in harvested sites. These differences were most pronounced on snags. Specifically, unharvested sites contained high‐longevity snags (kelo trees), which hosted unique lichen communities with higher lichen richness than any other studied substrate, including the highest numbers of red‐listed and deadwood‐dependent species.Synthesis and applications. Retention forestry can support lichen assemblages associated with living Pinus sylvestris. However, maintaining deadwood‐associated lichen diversity through retention practices entails significant challenges. Deadwood‐associated lichen diversity relies on high‐longevity snags and is not sustained by the habitats provided in retention forestry. Biodiversity maintenance in forest management requires comprehensive provision of the habitat features of unmanaged forests, such as a qualitatively representative deadwood profile, which can prove difficult. [ABSTRACT FROM AUTHOR]

Forests are critical to water resources, but high evapotranspiration (ET) can reduce water yield. Thinning and prescribed fire reduce forest density and often reduce ET, promoting higher water yield. However, results from such treatments have been inconsistent, possibly because of unknown interactions among individual ET components. We compare water budget components of longleaf pine (Pinus palustris Mill.) woodlands with frequent prescribed fire to the water budget components of fire‐excluded stands. We hypothesized that fire exclusion would result in higher ET due to increased midstory transpiration (Et) and interception (Ei), and higher evaporation from litter (Ilitter). Reference plots were burned every two years while treatment plots had fire excluded for 15–20 years. Fire treatments were repeated in two sites representing a soil moisture gradient, noted as mesic and xeric. We measured woody Et using sap flux, and we modeled groundcover Et using physiological models. We measured Ei of canopy and groundcover layers, modeled Es litter biomass, and constructed a total component‐based water budget for each site and treatment. Compared with reference plots, midstory Et was 300%–800% higher in fire exclusion plots. Groundcover Et was ~80% less than reference treatments, countering the effects of midstory growth on total ET. Stand Ei followed similar trends, with groundcover Ei in reference plots countering the effects of midstory and litter Ei in fire exclusion plots. As expected, total ET in the xeric site was 18% higher in fire exclusion plots. However, ET in the mesic site was 16% lower in the fire exclusion plots due to high groundcover Et and Ei in reference plots. Thus, our results show that fire exclusion changes total forest ET, but the size and direction of the effect vary depending on the balance between midstory and groundcover transpiration and interception. These results highlight the importance of groundcover in ecosystem function in low‐density forests and may help explain inconsistent results from studies of water yields following thinning and fire. While prescribed fire is a valuable tool in forest management, we suggest that the effects of fire on ET are complex and require careful accounting of all water fluxes within a forest ecosystem. [ABSTRACT FROM AUTHOR]

Guidelines for international reporting of greenhouse gas emissions and removals in the forest sector require a land-based approach that includes all lands subject to forest management activities such as harvest, forest inventory, regeneration, management of natural disturbances, and protected areas. The reported net greenhouse gas balance of managed forests is not limited to forest stands resulting from timber harvest and wood product use. Reporting guidelines specify methods to reduce interannual variability in reported emissions attributable to natural disturbances. In Canada, the initial (1990) assignment of all inventoried stands to anthropogenic or natural disturbance reporting categories is determined by the last stand-initiating disturbance. A new compilation of historic (1889 to 1989) harvest data in Canada reduces the area reported in the anthropogenic category by 34 million hectares (20%) in 1990. This area transfer from anthropogenic to natural origin reduces the carbon sink reported as anthropogenic by 113 Mt CO2e yr−1 (56%) in 1990 and by 30 Mt CO2e yr−1 (23%) in 2021. [ABSTRACT FROM AUTHOR]

Due to their high variability, the growth responses of western hemlock (Tsuga heterophylla (Raf.) Sarg.) stands to fertilization have been regarded as unresponsive or inconsistent. Tree-level fertilization response models for western hemlock were constructed to clarify the inconsistent stand-level responses, using extensive datasets from the United States and Canada. Tree growth in diameter and height, mortality, were assessed by fertilization, stand- and tree-level variables using generalized linear and nonlinear mixed-effects models. Western hemlock fertilization response was influenced not only by stand-level variables and application rates but also by tree social status and crown characteristics. Greater dominance and crown ratio in trees increased height growth responses but decreased diameter growth. The peak of fertilization effect on diameter growth was observed 3 years after application, while effect on height growth peaked at 6 years. Fertilization increased the overall mortality rate, but also ameliorated it for suppressed and steady-growing trees. These complicated fertilization responses of western hemlock may imply its tolerance and allocation strategy of resources at a given size and social status. The results highlight the importance of adopting a tree-level modeling approach to better understanding how western hemlock trees respond to fertilization, improving the accuracy of growth and yield prediction after fertilization. [ABSTRACT FROM AUTHOR]

Forestry is an important component of Canada's economy with British Columbia (BC) contributing almost half to the national roundwood production. Yet, the country's timber supply and forest economy are threatened by climate change, with increased frequency and severity of natural disturbances and changes in forest productivity. Mountain pine beetle (Dendroctonus ponderosae) outbreaks are endemic in BC, but the latest climate change-driven outbreak has resulted in a cumulative loss of over half of all merchantable pine, leading to a mid-term timber supply shortage. In this study, we investigate the potential of commercial thinning and alternative planting regimes based on species diversification and assisted species migration to mitigate the anticipated decrease in timber supply in BC. We simulated the long-term effects of these management options in a case study area in interior BC, using a toolbox that combines management- and research-oriented data and models. We found that combining commercial thinning and species diversification has the best potential to mitigate future timber supply shortages in BC. We discuss the limits of this toolbox approach and identify research needs and recommendations for future studies aiming at modelling cumulative effects of management, climate change, and natural disturbances on timber supply. [ABSTRACT FROM AUTHOR]

Urban forest management is a multistakeholder, multi-objective situation whereby a surfeit of synergistic or competing goals may exist. Greater research and applied guidance for what works in which urban forest contexts could help improve urban tree and forest outcomes. The challenge in conducting research of this nature is systematic definitions of "what works" and "which contexts" across multidimensional, polycentric urban forest social-ecological systems. This paper presents a comprehensive framework for studying the complexities in urban forest systems (synthesized from numerous other frameworks in the field) that could be used to generate context-specific insights into urban forest management and dynamics. The logic of using frameworks and specific frameworks that already exist within the field are reviewed. Then, I present the urban forest social-ecological system (UFSES) framework. The UFSES framework specifies 5 first-tier factors: the Characteristics of Trees in the Urban Forest (T); the Surrounding Growing Environment (E); Management & Institutions (M); and Characteristics of the Human Community (H); which influence Urban Forest Outcomes (O). A detailed set of second-tier variables nested within these factors are presented in tables at the end of the paper. The framework can foster holistic systems thinking in a systematic yet flexible way; provide a working draft of a common language for thinking about and studying urban forest systems; and enable comparative case research. [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]

Societal Impact Statement: Unmanned aerial vehicle (UAV) imagery highlights the extent of illegal deforestation in protected areas for the biodiverse humid forest of central Madagascar. The ultra‐high‐resolution (<10‐cm pixel) images enable the creation of detailed forest 3D base maps and provide the means to quantify forest stand losses. To help communities safeguard their forests, local non‐governmental organisations can use UAV maps in combination with weekly deforestation alerts to facilitate an immediate on‐ground response that significantly restricts illegal activity. Integrating ultra‐high‐resolution UAV mapping and coarse‐resolution freely available satellite imagery should have much wider applications in Madagascar and the humid tropics for community‐based conservation. Summary: This study of the Ambohimahamasina humid forest shows that small UAVs offer a detailed (<10‐cm pixel), rapid and cost‐effective solution to provide maps of detailed deforestation patterns not visible in satellite imagery.Calculating forest extent and volume are valuable ways to rapidly assess forest losses and prioritise areas for ground patrols. The use of 3‐dimensional measurements for above ground carbon estimates indicate how, in the future, these metrics could be used to calculate carbon payments for conservation programs.By combining UAV and free satellite imagery, an effective alert system has been developed that supports community initiatives in the protection of their natural forest resources.The wealth of ultra‐high‐resolution UAV data collected in this study provides insights into forest dynamics, supports local community forest management, and has the potential to measure the value of the forest. [ABSTRACT FROM AUTHOR]

Forest management practices creating small‐scale forest edge habitats in managed forests have substantial impacts on the formation of beetle assemblages.In 2021, we conducted research in a managed oak woodland in Central Slovakia using three flight interception traps (FITs) to study beetle assemblages. Two FITs were installed at the forest edge, facing both, the clearing and the closed‐stand forest, while the third FIT was positioned 100 m within the closed‐canopy forest. We employed a novel methodological approach, which involved separately collected subsamples within the ecotone using FITs differentiated as 'ecotone inwards' and 'ecotone outwards' to capture distinct directional movements at the edge.We recorded 5.997 beetle specimens, encompassing 417 species across 284 genera and 58 families. We found that the species diversity and abundance of beetles were not significantly different between the FITs. However, the species composition was significantly different.The partial detrended canonical correspondence analysis suggests that these compositional differences might be closely associated with the distribution of trophic guilds, indicating varied responses to habitat modifications induced by forest edge creation. The results of our study showed that phloephagous, saproxylophagous, xylomycetophagous, xylophagous and zoophagous beetles exhibited a positive association with the forest edge, while mycophagous, phytophagous and saprophagous groups were distinctly associated with the closed‐canopy forest.Our analyses indicated that the 'ecotone outward' part of forest edges of managed forest may attract higher number of trophic groups, while the 'ecotone inward' part of the forest edge hosted high abundances of phloephagous and xylomycetophagous species. [ABSTRACT FROM AUTHOR]

The crises of climate change and biodiversity loss have pushed the aim for increasing the resilience of forest ecosystems high on the agenda of foresters and policymakers. At the same time, synergistic opportunities for restoring forests and biodiversity are emerging to safeguard these ecosystems. Naturalness is a key characteristic of forest ecosystems, which should be considered when estimating benchmarks for resilience and biodiversity conservation. The naturalness of forest ecosystems is highly dependent on the intensity of human activity, as different levels of management intensity can change the original traits of forest ecosystems. This paper presents an archetypal typology of forest ecosystems, describing the association between management and naturalness. Both features are represented as gradients covering the full spectrum observed in European forests. The array of forest ecosystem archetypes was verified using case studies across Europe. The typology provides useful information for setting targets for resilience and restoration of forest ecosystems. [ABSTRACT FROM AUTHOR]

Forest management practices influence soil fertility and nutrient availability through different mechanisms. Despite the importance of soil fertility and nutrient availability in forest ecosystems, there is limited research on the effects of management practices on soil properties in mixed-species forests. This study investigates the impact of different management types (community forest area (CFA), Forest area (FR), and Sacred Grove (SG)) on soil physicochemical properties, organic matter, and organic carbon storage in Benue State, Nigeria. Soil samples from three forest management types were collected and analyzed using established laboratory standard procedures. Descriptive statistics, analysis of variance, and correlation analysis revealed significant differences (p<0.05) in soil texture, pH, organic carbon, and total nitrogen across the management types. CFA and FR were predominantly sandy loam soils, while SG had higher clay loam content. Soil pH ranged from 4.82 - 6.07 with SG having the highest pH value (6.07). The forest reserve has the highest sand content (75.0%) and SG has the highest clay content (34.6%). The highest soil organic matter content (3.13%) was recorded under CFA, while organic carbon of 1.83% was recorded under FR. The highest values of Mg (0.97 Cmol/kg), N (0.28%), P (3.77 ppm), K (0.20 Cmol/kg) Na (0.18 Cmol/kg), and Ca (1.24 Cmol/kg) were at their peak under the Sacred grove management types. Thus, the various types of forest management significantly impact soil properties and organic carbon content in the study area. It is recommended that SG or CFA management should be adopted for forest resource conservation in the study area. [ABSTRACT FROM AUTHOR]

To apply the analytic hierarchy process (AHP) to solve forest management problems, it is necessary to determine when the use of this method is appropriate and when another method would be more appropriate due to the limitations of the method itself. In this study, strengths, weaknesses, opportunities, and threats (SWOT) and meta-SWOT analyses were conducted to assess the applicability of the AHP method to sustainable forest management problems. Sixteen experts from 11 different European countries participated in the research. First, they evaluated the AHP method from the SWOT perspective and weighted the SWOT factors and groups using the AHP method. The results showed that the AHP method is more suitable for application in sustainable forest management than other multicriteria decision-making (MCDM) methods with respect to two competitive dimensions: design and calculation. However, the application of the AHP in sustainable forest management also has some weaknesses and threats that should be considered. Involving stakeholders with expertise and skills in model development and pairwise comparisons is the most important issue in this area; otherwise, incorrect results could be obtained for forest management decisions. Problem-solving conditions such as uncertainty, the interactions among criteria and the economic constraints of the problem may also lead to the use of other methods instead of the AHP in sustainable forest management. The results of this study contribute to global studies on decision-making in natural resource and environmental management, especially decisions related to forest management. [ABSTRACT FROM AUTHOR]

Forest and biomass crops for bioenergy and bioproducts can promote a sustainable bioeconomy while effectively reducing greenhouse gas (GHG) emissions to mitigate global warming. One of the most concerning issues is selecting and using appropriate modeling and analytical technologies to optimize the benefits of multi-feedstock biomass supply chains, including logistics. Machine learning (ML) has been used to solve increasingly complex supply chain problems, providing powerful tools for sustainable forest management and biomass resource development. Existing research is extensive and spans many different ML techniques, but synthesis is needed to help guide the adoption of these rapidly evolving tools. This review summarizes ML applications in forest and biomass supply chain management in terms of data, algorithms, and process examples, with an emphasis on direct application to supply chain management. ML is a viable technique to support strategic, operational, and tactical planning and decision-making in this field and can enhance the environmental and economic performance of diverse forest and biomass supply chains. [ABSTRACT FROM AUTHOR]

High costs primarily pose challenges to forest management in planning and executing the repair of forest roads. With budget limitations and inadequate oversight, it has become critically essential to monitor the state of these roads. Monitoring the condition of forest roads has become imperative, driven by budget constraints and a lack of effective supervision. While smartphones have proven effective in detecting road defects on public roads, their application on forest roads is hindered by the absence of suitable indices and software infrastructure. Addressing this gap, this research focuses on the development of the Forest Road Pavement Condition Index (FRPCI) to facilitate smartphone-based monitoring. We collected and compared data from 4 kilometers of forest roads, employing two traditional harvesting methods alongside smartphone sensor data. Utilizing deep learning methods, including Convolutional Neural Network (CNN), Long-Short Term Memory (LSTM), and CNN-LSTM, we processed the collected data. Signal processing using GPS data, coupled with wavelet transformation, demonstrated promising results with an accuracy and recall exceeding 80%. The proposed system functions as a distributed information system, transitioning data from organizational mode to field mode. It measures damage, assesses forest road conditions, and leverages image processing and GPS technologies. This monitoring system technology offers capabilities for preparing, storing, updating, maintaining, and analyzing diverse information. Importantly, adopting this method can significantly reduce operating costs, making forest road monitoring for maintenance purposes more feasible. [ABSTRACT FROM AUTHOR]

This article examines the construction of the land-water binary in the Sundarbans delta in colonial South Asia. It argues that this division was racially motivated and used to justify colonial rule. The article criticizes current river studies scholarship for perpetuating this divide and calls for a reevaluation of approaches to environmental studies. It also highlights the need to analyze the social dynamics and power structures surrounding water resources, particularly in relation to caste-based oppression. The article concludes by emphasizing the importance of understanding the complexities of water access and usage beyond the traditional land-water binary. [Extracted from the article]

The study investigates the long-term impact of Lophodermium needle cast on open-pollinated Scots pine progenies in Latvia. A significant impact of cumulative needle cast damage on growth and survival was found. Notably, 51% of trees experienced severe damage after the 4th growing season. Genetic factors played a role in survival at 12 years. Height growth was significantly affected, with height at age 3 and cumulative needle cast damage as key predictors for heights at ages 12 and 16. Genetics demonstrated a substantial impact, with heritability coefficients of 0.25 for cumulative needle cast damage and 0.24 for height, and negative genotypic correlations (rG ≥ -0.71) between the traits. Selecting the top 10% families based on height at 12 years yielded a 14.2% improvement in height and a simultaneous 8.4% reduction in cumulative needle cast damage, enhancing survival by 9.8%. Thinning somewhat mitigated the negative effect of needle cast. The findings highlight the need for adaptive forestry strategies in the Baltic Sea region. [ABSTRACT FROM AUTHOR]

If soil compaction caused by the operation of forestry machines does not suppress the growth of planted seedlings, this operation may be an alternative method to conventional weeding for controlling vegetation competition. To evaluate the effects of soil compaction and vegetation weeding on the seedlings of three boreal evergreen coniferous species, a field experiment was conducted for two years. Under the weeding conditions, the main target species, Abies sachalinensis, which has thick fine roots, showed relatively robust belowground growth under soil compaction compared with the other Picea species, which has thin fine roots. Soil compaction suppressed the density and height of the vegetation, mitigating the light conditions. In A. sachalinensis seedlings, the leaf mass per area, nitrogen content per leaf area, and specific root length of fine roots showed positive responses to the weeding treatment without soil compaction. No weeding suppressed the relative growth rate in terms of the root collar diameter and aboveground volume, while these changes were not observed under soil compaction. Both the results of the light conditions and the responses of the seedlings indicated that the competitive conditions were weakened by soil compaction. These results suggest that when planting functional types with thicker fine roots, such as A. sachalinensis, operation of forestry machines may contribute to forest vegetation management. [ABSTRACT FROM AUTHOR]

This study investigates the resilience of indigenous knowledge in five Karen villages, located in Thailand's Chiang Mai, Chiang Rai, and Lampang provinces, that have been recognized for best practices in community forest management (CFM). The CFM model was initiated by local communities to promote forest conservation and community engagement. Data on CFM practices, land-use rights, social networks, and indigenous knowledge were collected through 17 in-depth interviews and 5 focus group meetings. The findings include how these Karen communities have adopted payment for environmental services (PES) to fund conservation projects and social welfare. More specifically, PES generates social capital by facilitating coordination with stakeholders from the private sector, academia, and government. These social networks promote markets for local products and advocate for indigenous land-use rights. The PES model also serves as a tool whereby Indigenous Peoples can shape their identities as innovative forest guardians and legitimize their residence within the forest. Additionally, the study reports on how Karen people have diversified their livelihoods to include hosting academic tourism, handicrafts, and livestock, reducing their dependence on forest resources. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The identification of climate anomalies associated with large-scale stand disturbances can help inform climate-focused forest management. In the spring and summer of 2018, an unusual spike in balsam fir (Abies balsamea) mortality was reported in multiple areas across its southern distribution range limit, from Wisconsin, United States, to New Brunswick, Canada. Such an event was previously reported in 1986 in the study region and referred to as Stillwell's Syndrome. To identify the role of climate anomalies in the 2018 event, we used monthly climate anomalies as explanatory variables in a Random Forest model predicting the presence of mortality from air and field-based surveys across the Maritimes region of eastern Canada. Results were validated by (1) comparing common climate predictors of mortality from this model and a separate Random Forest model fitted on the 1986 event, and (2) using the 2018 model to predict areas of mortality in 1986. Both the 1986 and 2018 models identified multiple common climate anomalies. Areas with unusually high water deficit and temperatures in the previous growing season, followed by thick April snowpack and high May temperatures the same year, were associated with balsam fir mortality. Such climate anomalies have been previously associated with water stress and desiccation in trees. When using the 2018 model to map the occurrence of mortality in 1986 using historical climate data, we report a 95% accuracy in prediction (kappa = 0.88). The approach used here in conjunction with mapped records of past stand disturbances could help with understanding the impacts of future climate anomalies and adaptive management strategies to deal with these events. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainable forestry typically involves integration of several economic and ecological objectives which, at times, may not be compatible with one another. Multi-objective prioritization via harvest scheduling programs can be used to elucidate these relationships and explore solutions. One such program is a spatially explicit harvest scheduler that adopts the Metropolis-Hastings algorithm to iteratively find management solutions to achieve multiple objectives (Habplan). Although this program has been used to address forest management scheduling and simulation-based tasks, its utility is constrained by time-intensive data preparation and challenges with incorporating spatial configuration objectives. To address these shortcomings, we introduce an open-source software package, HabplanR, streamlines data preparation, sets parameters, visualizes results, and assesses spatial components of ecological objectives. We developed four example objectives to incorporate into a multi-objective management problem: habitat quality indices for three species "types" (open, closed, and intermediate-canopy-associated species), and harvested pine pulpwood (revenue). We demonstrate the utility of this package to find management schedules that can accommodate potentially conflicting habitat needs of species, while achieving economic targets. We produced 100 software runs and prioritized individual objectives to select four management schedules for further comparisons. We compared outcome differences of the four schedules, including a spatial comparison of two high performing schedules. The software package makes costs and benefits of different schedules explicit and allows for consideration of the spatial configuration of management outcomes in decision-making. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing demand for forest certification and certified forest products in Europe. This trend is related to major worldwide challenges, such as the need to decarbonize the economy and mitigate climate change but also social and consumer demands for wider fair trade. However, whether forest certification influences economic valorization in forestry remains a question. The aim of this study is to analyze forest certification levels across Europe and identify potential relationships between the level of certification in forest areas and relevant economic indicators at country level. This study collected openly available data on total and certified forest areas, economic indicators, and environmental indicators for 28 European countries and explored the correlation between certified forest areas and economic performance in the forestry sector. Findings show that forest certification can significantly improve the economic performance of European forests. It has a more pronounced positive effect on economic incomes than on costs' reduction. While certification costs do rise with the extent of forest area, they tend to stabilize at larger scales, suggesting that the certification process is economically sustainable and scale is relevant. Czechia and the Netherlands stand out for having the highest net values added related to forest certification, reflecting an effective economic exploration of forest resources. This study offers new perspectives to natural and social scientists, as well as to industry and policy makers, by proving contextualized data to support decision making. Additionally, it provides hints for further studies and policy guidelines on sustainable development and the impact of forest certification schemes. [ABSTRACT FROM AUTHOR]

Natural climate solutions (NCS) and transitioning to clean energy can reduce greenhouse gases and contribute to mitigating climate change. Private landowners with large holdings, such as conservation organizations like The Nature Conservancy, have set ambitious goals to reduce net emissions and increase sequestration on their lands by implementing NCS. We assessed the potential carbon dioxide-equivalent (CO2e) reduction from feasible NCS, specifically implementing new restoration and agricultural management activities, and transitions to clean energy on The Nature Conservancy, California chapter's fee-owned and conservation easement properties. We compared the total CO2e reduction from potential new NCS activities to the impact from ongoing NCS activities, the chapter's 2030 goal, and the state's reduction goal for natural and working lands to understand how the organization can contribute to climate mitigation. We found that implementing NCS on 37 fee-owned properties (63,175 MTCO2e year –1) and clean energy on 10 fee-owned properties (488 MTCO2e year –1) combined would not reach the chapter's 2030 goal (72,000 MTCO2e year –1), and there can be tradeoffs between maximizing CO2e reduction and protecting conservation values. However, ongoing changes to forest management on a single conservation easement property, where another non-profit harvests timber and sells carbon credits, currently contributes 147,749 MTCO2e year –1, more than two times the 2030 goal and representing 7.4% of the state's annual goal. Our results suggest that The Nature Conservancy, California chapter would need to implement NCS on some of the conservation easements or consider future land protection deals with carbon rich ecosystems or high impact NCS to reach their CO2e reduction goal. [ABSTRACT FROM AUTHOR]

Global deforestation and forest degradation threaten the sustainability of natural and human systems. Forest landscape restoration, through active approaches such as plantations, woodlots, boundary planting, and agroforestry, and passive approaches like exclosures, presents an opportunity to mitigate adverse effects, enhance ecosystem service recovery, and associated benefits for livelihoods. Here, using different spatial scales, we compare the contribution of both approaches to the recovery of plant diversity in southern Ethiopia. Using forest inventory data (891 plots) from multi‐aged stands, we estimated and compared alpha (α), beta (β), and gamma (γ) diversity in regeneration and tree layers between the approaches. We observed increasing α‐diversity in the order grazing lands‐active‐passive‐forest sites. β‐Diversity revealed similarity between passively restored sites and natural forests. γ‐Diversity was higher in active restoration for the regeneration layer, but passive restoration had higher γ‐diversity in the tree layer. For both approaches, γ‐diversity was consistently highest in intermediate‐aged stands (10–20 years). Results highlight the potential of active restoration strategies to facilitate vegetation recovery in human‐dominated landscapes, especially when management allows natural regeneration, while stand age variation may be associated with disturbance intensities for both approaches. Our results support a paradigm shift toward implementation of a mixture of these approaches in the landscapes to meet increasing human demands while restoring important ecosystem services like biodiversity. We recommend enhancing species diversity on restored sites to improve performance and ecosystem service recovery. On actively restored sites, we recommend protecting regenerated species; on passively restored sites, enrichment planting, increased protection, and sustainable utilization. [ABSTRACT FROM AUTHOR]

Although the relationship between biodiversity and ecosystem functionality (BEF) has been studied comprehensively, how the mixing ratio of tree species in mixed forests affects the response of trees to climate and drought remains an unexplored and rather unknown question. Hence, we established tree-ring chronologies for Pinus tabuliformis Carr. (P) and Quercus variabilis Blume. (Q) mixed forests with different mixing ratios. In the temperate region of China, we investigated three mixing ratios: 90% P and 10% Q (P9Q1), 60% P and 40% Q (P6Q4), and 20% P and 80%Q (P2Q8). We collected tree ring samples using three tree size categories: dominant, intermediate, and suppressed trees. We explored the climate sensitivity of these trees and their drought tolerance indices– resilience (Rs), resistance (Rt), and recovery (Rc) under two drought conditions: short-term drought (1993 drought) and long-term drought (1999-2015 drought). P6Q4 made P. tabuliformis more sensitive to the Palmer drought severity index (PDSI) from the previous year than the other two ratios. The effect of the mixing ratio on drought response was insignificant under short-term drought in both tree species. Rt, Rc, and Rs of P. tabuliformis decreased with an increasing Q. variabilis:P. tabuliformis ratio in long-term drought. Rt, Rc, and Rs of Q. variabilis were the highest in P6Q4. The sensitivity of trees to PDSI varied among classes and was influenced by the mixing ratio. Dominant trees were most sensitive to PDSI in P6Q4 and P2Q8, whereas intermediate and suppressed trees were more sensitive to PDSI in P9Q1. The impact of tree size on drought tolerance indices varied according to drought type and mixing ratio. These findings showed that the mixing ratio has a confounding effect on the drought sensitivity of temperate tree species. Differences in hydrological niches allow Q. variabilis to benefit from mixing with P. tabuliformis. Mixing with optimal proportion of P. tabuliformis maximizes the drought resilience of Q. variabilis. Additionally, weakly competitive species (P. tabuliformis) do not benefit from mixed forests during prolonged water deficits. This result complements previous arguments that species mixing reduces the biological vulnerability of individuals. This study emphasizes the importance of species selection based on the biological and physiological characteristics of tree species in the afforestation of mixed forests. It highlights the critical role of species mixing ratios in the resistance of mixed forest ecosystems to climate change, which may provide a reference for sustainable forest management. [ABSTRACT FROM AUTHOR]

Forests are invaluable natural resources that provide essential services to humanity. However, the effects of global warming on forest carbon and nitrogen cycling remain uncertain. Here we project a decrease in total nitrogen input and accumulation by 7 ± 2 and 28 ± 9 million tonnes (Tg), respectively, and an increase in reactive nitrogen losses to the environment by 9 ± 3 Tg for 2100 due to warming in a fossil-fueled society. This would compromise the global carbon sink capacity by 0.45 ± 0.14 billion tonnes annually. Furthermore, warming-induced inequality in forest carbon and nitrogen cycles could widen the economic gap between the Global South and Global North. High-income countries are estimated to gain US$179 billion in benefits from forest assets under warming, while other regions could face net damages of US$31 billion. Implementing climate-smart forest management, such as comprehensive restoration and optimizing tree species composition, is imperative in the face of future climate change. Global warming may widen the development gap between the Global South and North by increasing inequalities in forest carbon and nitrogen cycling. High-income countries are expected to benefit from forest assets, while others face net losses. [ABSTRACT FROM AUTHOR]

The article explores the intricate relationship between basic human values and forest ecosystem services (FES). The study highlights the critical role that forests play in providing essential services for biodiversity, forest products, climate stabilization and human well-being, and emphasizes the need to understand and integrate human values into forest management and planning. Through a novel approach, this study explores how the concept of "forest" can elicit considerations of fundamental human values that diverge from conventional classifications and measurements of forest values. The study uses a comprehensive methodology, including surveys and content analysis, to uncover the hierarchical structure of human values associated with forests. This approach enables the identification of fundamental values that remain constant despite situational variations. The main results reveal a hierarchical structure of values, with Apollonian values being more prevalent than Dionysian ones. The study shows significant differences in the importance attributed to different FES, reflecting underlying value differences between residents. The study makes a novel contribution by systematically examining the links between human values and FES and proposing a profound and sustainable approach to forest management that takes into account the psychological dimensions of humanforest interactions. The study suggests that recognizing and incorporating the intrinsic human values into forest ecosystem service frameworks can improve sustainable forest management practices and ultimately foster a deeper connection between people and the forest environment. [ABSTRACT FROM AUTHOR]

Karst ecosystems, especially tropical karst forests, are crucial to the global carbon cycle. In mountainous and hilly areas, elevation-related changes in environment and vegetation often lead to shifts in the accumulation and decomposition of soil organic carbon (SOC). However, the elevational patterns and influencing variables of SOC and its fractions in tropical karst forest ecosystems remain largely unexplored. Here, we analyzed the elevational patterns of SOC and its fractions in the topsoil and subsoil in the tropical seasonal rainforests within typical peak-cluster depression region of Southwest China. Our results indicated that the SOC content was highest at 400 m asl, which was significantly higher than that at 200 m asl (p < 0.05). Overall, SOC content demonstrated an increasing trend with rising elevation. Additionally, SOC content was significantly higher in the topsoil compared to the subsoil (p < 0.05). The majority of SOC fractions exhibited an increase with elevation but decrease with soil depth. Notably, only water-soluble organic carbon (WSOC) displayed a decrease with elevation. Meanwhile, recalcitrant organic carbon (ROC, 54.27%), particulate organic carbon (POC, 30.19%), and easily oxidizable organic carbon (EOC, 16.95%) were the main SOC fractions. Labile organic carbon (LOC) in the karst forest soil was predominantly composed of EOC and POC. Correlation analysis unveiled significant positive correlations between SOC and certain fractions with elevation, soil total nitrogen, and exchangeable magnesium. Conversely, significant negative correlations were observed with soil bulk density (SBD), soil total phosphorus, and litter phosphorus (Litter P). Redundancy analysis indicated that elevation, SBD, and Litter P were the main environmental variables influencing shifts in SOC and its fractions. Structural equation models showed that SOC was primarily directly impacted by soil properties but indirectly impacted by elevation. ROC was mainly associated with the direct effects of soil properties and litterfall, although elevation exerted a substantial impact through indirect pathways. Moreover, LOC was predominantly influenced by the direct impact of soil properties. Therefore, this study demonstrates that SOC and its fractions are strongly influenced by elevation in karst peak-cluster depression regions and have important implications for forest management and sustainable ecosystem development in these regions. [ABSTRACT FROM AUTHOR]

Forest biomass estimates are required for many applications, including accounting for the role of forests in the global carbon cycle, supporting sustainable forest management and making informed decisions. For all these applications and others, accurate and reliable forest biomass estimates are required. This study evaluated the potential of Sentinel-2 data for predicting and mapping aboveground biomass (AGB) of a dry Afromontane Forest in Tigray, Northern Ethiopia. Multiple linear regression was employed to model the relationship between AGB and Sentinel-2-derived spectral variables. The evaluation criteria for best-fit model selection were based on the coefficient of determination (R2), root mean square error (RMSE, %), and bias (Bias, %). All the spectral variables evaluated here were significantly correlated with AGB (p < 0.01). The model that includes a fraction of photosynthetically active radiation (FAPAR), leaf area index (LAI), Band 2 and Band 3 as predictor variables provided the best predictive performance for AGB in the study area (R2 = 0.38, RMSE = 13.62 Mg ha−1 and Bias = -3.10 Mg ha−1). The predicted AGB of the study area ranges from 0.1 to 141.8 Mg ha−1, with a mean value of 12.4 Mg ha−1. The results from this study suggested that Sentinel-2 data can be potentially applied for estimating and mapping AGB in dry Afromontane forests. [ABSTRACT FROM AUTHOR]