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Forests worldwide are under increasing pressure from climate change and emerging diseases, threatening their vital ecological and economic roles. Traditional breeding approaches, while valuable, are inherently slow and limited by the long generation times and existing genetic variation of trees. CRISPR technologies offer a transformative solution, enabling precise and efficient genome editing to accelerate the development of climate-resilient and productive forests. This review provides a comprehensive overview of CRISPR applications in forestry, exploring its potential for enhancing disease resistance, improving abiotic stress tolerance, modifying wood properties, and accelerating growth. We discuss the mechanisms and applications of various CRISPR systems, including base editing, prime editing, and multiplexing strategies. Additionally, we highlight recent advances in overcoming key challenges such as reagent delivery and plant regeneration, which are crucial for successful implementation of CRISPR in trees. We also delve into the potential and ethical considerations of using CRISPR gene drive for population-level genetic alterations, as well as the importance of genetic containment strategies for mitigating risks. This review emphasizes the need for continued research, technological advancements, extensive long-term field trials, public engagement, and responsible innovation to fully harness the power of CRISPR for shaping a sustainable future for forests. [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]

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]

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]

Mixed tree plantations containing nitrogen (N2)-fixing species have the potential to enhance C sequestration, soil biodiversity and forest productivity. Here, we investigated the impact of Acacia mangium and Eucalyptus urophilla x E. grandis mixed plantations in the Congolese coastal plains on soil mycobiota community structure and diversity by ITS metabarcoding sequencing and bioinformatic analysis. Higher Faith's phylogenetic diversity and Evenness' was found in Eucalyptus monoculture relative to stands containing Acacia. Differences in beta diversity were found among Eucalyptus and Acacia monoculture, and mixed-species stands highlight the effects of plant species on fungal community structure. Ascomycota, Basidiomycota and Rozellomycota phyla were predominant in all stands, with both Dikarya (Ascomycota and Basidiomycota) accounting for more than 70% in all stands. Correlation analysis revealed that sulfur (S) was the most correlated soil attribute with the three predominant phyla but also with Mucoromycota and Calcarisporiellomycota phyla, although mostly negatively correlated (4 out of 5). Phosphorus was mostly positively correlated to soil attributes (3 out of 4) and nitrogen was correlated twice, positively and negatively. Distance-based redundancy analysis revealed a positive correlation of nitrogen (p-value = 0.0019, contribution = 22%) and phosphorus (p-value = 0.0017, contribution = 19%) with soil mycobiota. A high prevalence of generalists (28% to 38%) than specialists (9% to 24%) were found among the different sites. In stands containing Acacia (pure and mixed species) the soil mycobiota harbor the prevalence of generalist strategies with the potential to withstand environmental stresses and utilize a higher number of resources against specialists in Eucalyptus stands. Stronger positive correlation between soil attributes and main fungal taxa, higher generalists' strategies and lower Faith's phylogenetic diversity and Evenness were reported in stands containing Acacia. This highlights the potential of mixed-species in preserving community stability following environmental disturbances and increasing the number of resources confirming their important ecological role in boosting the resilience of the forest ecosystems to climate and land-use (plant species as shown by PCA analysis) changes. [ABSTRACT FROM AUTHOR]

Climate change is increasingly recognized as a critical factor driving shifts in the distribution of dominant tree species within various forest ecosystems, including evergreen, deciduous, and thorn forests. These shifts pose significant threats to biodiversity and the essential ecosystem services that forests provide. In Tamil Nadu, India, where forest ecosystems are integral to both ecological balance and local livelihoods, there is an urgent need to predict potential changes in species distributions under future climate scenarios to inform effective conservation strategies. This study addresses this need by utilizing the MaxEnt species distribution model to assess the habitat suitability of dominant tree species in these forest types. The analysis spans current conditions (baseline period 1985–2014) and future projections (2021–2050) under the SSP2-4.5 emissions scenario, leveraging bioclimatic variables at a 1 km resolution. Key climatic factors such as annual mean temperature, precipitation of the driest month, and precipitation seasonality were identified as major drivers of habitat suitability, particularly in the Eastern and Western Ghats of Tamil Nadu. Model projections suggest a potential decrease in suitable habitat area by 32% for evergreen species and 18% for deciduous species, whereas thorn forest species might experience a 71% increase in suitable area. These findings underscore the critical need for targeted conservation actions to mitigate anticipated habitat losses and bolster the resilience of these vital forest ecosystems in the face of ongoing climate change. [ABSTRACT FROM AUTHOR]

Assessing resilience of wildfire-prone social-ecological systems (SES) can provide a baseline for decision makers and inform future management actions. In this study, we measure stakeholder perceptions of how SES resilience was influenced by historic 2020-wildfire events in northern Colorado and what actions they think are needed to enhance future resilience to wildfire. We developed a contextualized set of resilience principles and indicators based on the literature and expert opinion that included ecological, ecosystem service, and social categories. We conducted 15 stakeholder interviews and 37 surveys to characterize subjective measures of SES resilience. Stakeholders perceived that the resilience of ecological indicators pre- and post-wildfires remained mostly unchanged, but that ecosystem service indicators were negatively affected and social indicators positively affected. Related to future resilience, stakeholders underscored a need for more strategic fuel treatments, especially prescribed fire, and more collaboration and engagement across landowner types. Our findings highlight that wildfire events can have negative and positive effects on components of SES resilience, underscoring the need to disaggregate resilience components. Additionally, we find that stakeholder perceptions of resilience are in line with the literature on objective measures of post-wildfire resilience, suggesting that expert opinion can be used as a reliable method to measure resilience indicators in some contexts. [ABSTRACT FROM AUTHOR]

Managing forests to sustain their diversity and functioning is a major challenge in a changing world. Despite the key role of understory vegetation in driving forest biodiversity, regeneration and functioning, few studies address the functional dimensions of understory vegetation response to silvicultural management.We assessed the influence of the silvicultural regimes on the functional diversity and redundancy of European forest understory. We gathered vascular plant abundance data from more than 2000 plots in European forests, each associated with one out of the five most widespread silvicultural regimes. We used generalized linear mixed models to assess the effect of different silvicultural regimes on understory functional diversity (Rao's quadratic entropy) and functional redundancy, while accounting for climate and soil conditions, and explored the reciprocal relationship between three diversity components (functional diversity, redundancy and dominance) across silvicultural regimes through a ternary diversity diagram.Intensive silvicultural regimes are associated with a decrease in functional diversity and an increase in functional redundancy, compared with unmanaged conditions. This means that although intensive management may buffer communities' functions against species or functional losses, it also limits the range of understory response to environmental changes.Policy implications. Different silvicultural regimes influence different facets of understory functional features. While unmanaged forests can be used as a reference to design silvicultural practices in compliance with biodiversity conservation targets, different silvicultural options should be balanced at landscape scale to sustain the multiple forest functions that human societies are increasingly demanding. [ABSTRACT FROM AUTHOR]

To enhance forest resilience to predicted increases in forest stressors, managers increasingly desire ecologically based restoration approaches that increase ecosystem adaptation potential. Mixedwood stands, which contain a range of life history and functional traits, may be more resistant and resilient to ecosystem stressors. Management of Quercus–Pinus mixedwood stands includes the use of prescribed fire, which requires an understanding of vegetation-fuels-fire feedbacks in these ecosystems. However, a paucity of knowledge exists on the intra-stand spatial patterns of fire effects. We analyzed the effects of a newly initiated prescribed fire program on the intra-stand characteristics of understory woody plants and fuelbed composition and loading in a long-unburned Quercus–Pinus mixedwood stand in Tennessee, USA. We sampled vegetation and fuels in two plots, one that experienced two prescribed fires (burned plot), and one fire-excluded plot directly adjacent (unburned plot). On the burned plot, we recorded lower sapling and seedling densities across taxa. Spatial analysis of advance reproduction in the burned plot indicated a combination of patchy fire effects, canopy openings, and high-light understory environments. We documented significant reductions in total fuel mass. The combination of spatial analysis and ordination revealed that prescribed fires homogenized fuel loads within the burned plot. [ABSTRACT FROM AUTHOR]

• Trees affected by green attack were identified within a limited time window. • The detection rates increased from 0.3 to 0.8 two weeks before brood emergence began. • The highest separability was found in the green shoulder region (490–550 nm). • Green shoulder infection/curvature points shifted during vitality decline. • Indices were developed with higher accuracy and simplified with three bands. Forest stress monitoring and in-time identification of forest disturbances are important to improve forest resilience to climate change. Fast-developing drone techniques and hyperspectral imagery provide tools for understanding the forest decline process under stress and contribute to focused monitoring. This study explored and developed hyperspectral drone imagery for early detection of forest stress caused by European spruce bark beetle Ips typographus (L.), before offspring emergence, which is crucial in controlling the spread but has been shown to be challenging. This study challenges the highest possible detectability of infested trees using a hyperspectral drone system that provided images with very high spectral, spatial, and temporal resolutions in Southern Finland. Images were acquired bi-weekly, four times (T1, T2, T3, T4), covering 8 weeks from trees being attacked by the first filial generation (F1) to the beginning of second filial generation (F2) brood emergence. Very low separability was observed for the reflectance from healthy and attacked trees, but the first and second derivative reflectance captured vitality changes, with the green shoulder region (wavelengths 490–550 nm) exhibiting the highest separability of all wavelengths (400–1700 nm). We discovered that the peak and valley values of the first and second derivative curves in the green shoulder region consistently shifted with longer infestation time. Based on this finding, we developed green shoulder indices. The detection rates were 0.24–0.31 and 0.76–0.83 for T3 and T4, higher than commonly used VIs such as the Photochemical Reflectance Index and the Red Edge Inflection Position, with detection rates of 0.69 and 0.34 for T4, respectively. We also proposed simplified green shoulder indices using the reflectance from three bands that can be used with multispectral cameras and satellite images for large area monitoring of forest health. We concluded that the detectability of infestations was very low for the first month after attack, and then rapidly increased before brood emergence. We highlighted the great potential of green shoulder indices in quantifying the photochemical functioning of the vegetation under stress. The methodology can potentially be applied for early identification of forests with declining vitality caused by various sources of forest stress and disturbances, such as infestations, diseases and drought. [ABSTRACT FROM AUTHOR]

Soil moisture is a crucial variable mediating soil‐vegetation‐atmosphere water exchange. As climate and land use change, the increased frequency and intensity of extreme weather events and disturbances will likely alter feedbacks between ecosystem functions and soil moisture. In this study, we evaluated how extreme drought (2015/2016) and postfire vegetation regrowth affected the seasonality of soil water content (0–8 m depth) in a transitional forest in southeastern Amazonia. The experiment included three treatment plots: an unburned Control, an area burned every three years (B3yr), and an area burned annually (B1yr) between 2004 and 2010. We hypothesized that (a) soil moisture at B1yr and B3yr would be higher than the Control in the first years postfire due to lower transpiration rates, but differences between burned plots would decrease as postfire vegetation regrew; (b) during drought years, the soil water deficit in the dry season would be significantly greater in all plots as plants responded to greater evaporative demand; and (c) postfire recovery in the burned plots would cause an increase in evapotranspiration over time, especially in the topsoil. Contrary to the first expectation, the burned plots had lower volumetric water content than the Control plot. However, we found that droughts significantly reduced soil moisture in all plots compared to non‐drought years (15.6%), and this effect was amplified in the burned plots (19%). Our results indicate that, while compounding disturbances such as wildfires and extreme droughts alter forest dynamics, deep soil moisture is an essential water source for vegetation recovery. Plain Language Summary: As extreme droughts and wildfires have become more common in southeastern Amazonia, they could alter soil moisture availability, but the intensity of these compounding effects still needs to be understood. This study investigates the impact of the extreme drought of 2015/2016, postfire vegetation recovery, the return of water to the atmosphere, and their interacting effects on water distribution across the soil profile in three treatment plots: an unburned Control, an area burned every three years, and an area burned annually from 2004 to 2010. Contrary to expectations, we found that soil moisture in the burned plots decreased in the years following the last experimental fire (2010), even as the vegetation recovered. Drought events significantly reduced soil moisture across all plots, but this effect was amplified in the burned plots. As land use changes increase and climate change intensifies, such drought‐induced soil drying may become more common, exacerbating the impacts of wildfires on ecosystem resilience and forest health across much of the region. Key Points: During the driest months of the year, burned forests showed significant reductions in soil moisture compared with unburned forestsThe drought event of 2015/2016 caused greater reductions in soil moisture in the burned forest than in the unburned forestBoth burned and unburned forests increased water use throughout the 8‐m soil column from 2011 to 2018 [ABSTRACT FROM AUTHOR]

The editorial "Topicalities in the Forest Ecology of Seeds" focuses on the importance of forest seed farming to ensure a sufficient number of high genetic value fruit/seeds for tree species management. The special issue covers topics such as seed dormancy, desiccation tolerance, complex bioecological studies, and reproductive capacity in forestry. The articles provide valuable insights into the biological and ecological aspects of seeds, offering a scientific basis for forestry and nature conservation practices to enhance forest ecosystem health and biodiversity in the face of environmental challenges. [Extracted from the article]

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.)

Disturbances catalyse change in forest ecosystems, and a climate-driven increase in disturbance activity could accelerate forest reorganization. Here, we studied post-disturbance forests after the biggest pulse of tree mortality in Central Europe in at least 170 years, caused by drought and bark beetle (Scolytinae) outbreaks in 2018–2020. Our objectives were to characterize the early state of tree regeneration after mortality, quantify patterns of reorganization relative to undisturbed reference conditions and assess how management and patch size affect forest reorganization after disturbance. We surveyed 1244 plots in 120 patches under managed (salvage-logged, often planted) and unmanaged (deadwood remaining on site, no planting) conditions in Germany. We found that regeneration density on disturbed sites was high (median 11 897 stems ha−1), resulting from a cohort of advance regeneration. Disturbances were strong drivers of change, with indications for resilience on only 36.3% of patches. Reassembly (i.e. a change in species composition) was the dominant pattern of reorganization (61.5%), and Picea abies forests changed most strongly. Post-disturbance management facilitated forest change, particularly promoting a change in species composition. The strength of reorganization increased with patch size. We conclude that the recent wave of tree mortality will likely accelerate forest change in Central Europe. [ABSTRACT FROM AUTHOR]

Drought can cause significant disruption to forest ecosystems and may have long‐term impacts on the structure and function of ecosystems after the end of drought. This is the key to quantifying the ability of ecosystem to respond to disturbance events by comprehensively analyzing the impact of drought on vegetation, the lagged effect, and ecosystem resilience to drought. This article takes broad‐leaved forests and coniferous forests in multiple temperature zones of China as the object of study, using distributed lagged nonlinear model (DLNM) to construct a systematic method. Our results show that the main sensitive lagged time for coniferous forests and broad‐leaved forests is the first 3 months in various temperature zones, with the strongest lagged effect in the month when the drought incidents occur. Coping capacity represents ecosystems to remain stable during droughts, and we quantified the indicator by the ratio of the resistance (the difference between NDVI value before the drought and during the drought) to recovery (the difference between NDVI value after the drought and during the drought). When dealing with intensive drought events, the coping capacity of subtropical broad‐leaved forests (−0.67) and tropical broad‐leaved forests (−0.88) exhibit the strongest coping capacity (value tends to −1). Overall, vegetation growth in subtropical and tropical regions is less affected by drought compared to temperate and cold temperate zones. The research results help us understand the comprehensive impact of drought on vegetation and the strategies for different vegetation to cope with drought. [ABSTRACT FROM AUTHOR]

Forest resilience, the ecosystem's capacity to withstand perturbations and retain primary functions and characteristics, is an essential indicator in evaluating the fate of an ecosystem under rapid climate change. Detailed information about forest resilience change, such as number of changes, direction (reduced vs increased), timing (start/end year), or duration of the change, is critical but is often not well demonstrated at the global scale. Here, we applied lag-one autocorrelation (AC1) as a forest resilience indicator on time series MODIS vegetation index images from 2001 to 2022 and employed LandTrendr spectral-temporal segmentation algorithms to track forest resilience change. Our results showed that the resilience of global forests changed nearly 3 times on average, and over 50% of global forests had an overall downward trend from the early 2000s up to recently. However, the current condition is changing for the better globally with approximately 53% of global forests currently showing an increased resilience during the recent change, and average patches of reduced resilience becoming smaller and more scattered. Over half of the forests in arid and temperate domains still show decreased resilience recently, which highlights the need for improved management practices. [ABSTRACT FROM AUTHOR]

Natural disturbance‐based management (NDBM) is hypothesized to maintain managed forest ecosystem integrity by reducing differences between natural and managed forests. The effectiveness of this approach often entails local comparisons of species composition or diversity for a variety of biota from managed and unmanaged forests. Understory vegetation is regularly the focus of such comparison because of its importance in nutrient cycling, forest regeneration, and for wildlife. However, larger scale comparisons between regions with distinct species assemblages may require a trait‐based approach to better understand understory responses to disturbance. We compared the long‐term effects of retention harvesting on understory vegetation in two large experimental study sites located in eastern and western regions of the Canadian boreal forest. These sites included the Sylviculture en Aménagement Forestier Ecosystémique (SAFE) experiment and the Ecosystem Management Emulating Natural Disturbance (EMEND) experiment, located in the eastern and western regions of Canada, respectively. EMEND and SAFE share common boreal understory species but have distinct tree communities, soils, and climate. Both experiments were designed to evaluate how increasing tree retention after harvest affects biodiversity. Here, we examined taxonomic richness, functional diversity, and functional composition (using community trait mean values) of understory plant communities, and also examine intraspecific trait variability (ITV) for five species common and abundant in both experiments. We observed the limited impacts of retention level on richness, functional diversity, and functional composition of understory plants 20 years postharvest. However, ITV of leaf morphological traits varied between retention levels within each experiment, depending on the species identity. Common species had different functional responses to retention level, showing species‐specific reactions to environmental variation. Our result suggests that understory plant communities in the boreal forest achieve resilience to disturbance both in terms of interspecific and intraspecific functional trait diversity. Such diversity may be key to maintaining understory biodiversity in the face of future disturbances and environmental change. Our results reveal the significance of ITV in plant communities for understanding responses to forest harvesting and the importance of choosing appropriate traits when studying species responses to the environment. [ABSTRACT FROM AUTHOR]

HIGHLIGHTS In a first attempt to elaborate the principles of forest landscape restoration (FLR) into tangible steps, the International Tropical Timber Organization (ITTO) developed guidelines in 2020 bringing together the multiple aspects and considerations required to successfully carry out an FLR project or programme. The guidelines is aimed at practitioners and is detailed without being prescriptive. The guidelines provide direction at the policy, technical and operational levels for restoring degraded (production and protection) forests and formerly forested landscapes in tropical forest biomes and should be adapted as appropriate according to national and local circumstances. The guidelines and case studies provided therein can be used by policymakers and stakeholders to generate or streamline public (institutional) and market incentives needed to scale up FLR, given that many benefits stemming from restoration have no short-term market value. Further work to test and apply these guidelines would be useful. Interest in forest landscape restoration (FLR) is high, but there is limited guidance on how to implement it. In this contribution, we aim to synthesise the salient points of the voluntary FLR guidelines developed by ITTO (2020) and demonstrate their application through three case studies. The objectives of the ITTO guidelines are to increase the positive contributions of trees and forests to the ecological health, productivity and resilience of tropical forest landscapes and to generate forest products. The guidelines elaborate on the six principles of the Global Partnership on FLR, through a set of 32 guiding elements (GE) intended to promote enabling conditions for successful FLR implementation and outcomes. Going forward, we propose three tangible mechanisms to improve use of the guidelines: 1) bringing key elements of the guidelines into other global conventions interested in restoration; 2) running regional capacity building workshops for middle-level practitioners and decision-makers; and 3) a mechanism to collect lessons emerging from their implementation. L'intérêt dans la restauration du paysage forestier (RPF) est élevé mais les lignes directrices quant à son application sont limitées. Nous cherchons par cette contribution à synthétiser les points majeurs des lignes directrices pour la RPF volontaire développées par l'OIBT (2020) et à démontrer leur application dans trois cas d'étude. Les objectifs de ces lignes directrices de l'OIBT sont d'accroître les contributions positives des arbres et des forêts à la santé écologique, la productivité et la durabilité des paysages des forêts tropicales et de leur potentiel à générer des produits forestiers. Ces lignes directrices élaborent les six principes de partenariat global dans le domaine de la RPF a l'aide d'un éventail de 32 conseils visant à promouvoir des conditions à même d'assurer le succès de la mise en pratique de la RPF ainsi que celui de ses résultats. En regardant vers le futur, nous proposons trois mécanismes tangibles pour améliorer leurs mise en pratique: 1) transférer des éléments-clé des lignes directrices vers d'autres conventions globales intéressées par la restauration, 2) offrir des ateliers régionaux pour accroître la capacité des praticiens et des preneurs de décision à moyenne échelle et, 3) un mécanisme pour compiler les leçons tirées de leur mise en pratique. El interés por la restauración del paisaje forestal (RPF) es elevado, pero la orientación sobre cómo aplicarla es limitada. En esta contribución se pretende sintetizar los puntos más destacados de las directrices voluntarias sobre RPF elaboradas por la OIMT (2020) y demostrar su aplicación a través de tres estudios de caso. Los objetivos de las directrices de la OIMT son aumentar las contribuciones positivas de los árboles y los bosques a la salud ecológica, la productividad y la resiliencia de los paisajes forestales tropicales y generar productos forestales. Las directrices desarrollan los seis principios de la Alianza Global para la RPF, a través de un conjunto de 32 elementos rectores destinados a promover las condiciones propicias para la implementación exitosa de la RPF y sus resultados. De cara al futuro, se proponen tres mecanismos tangibles: 1) la incorporación de elementos clave de las directrices a otros convenios mundiales interesados en la restauración; 2) la organización de talleres regionales de fomento de capacidades para profesionales de nivel medio y responsables de la toma de decisiones; y 3) un mecanismo para recopilar las lecciones que surjan de su aplicación. [ABSTRACT FROM AUTHOR]

Riparian forests contribute to the resilience and biocomplexity of floodplains but may be catastrophically impacted by large floods. Forest disturbances will expose floodplains to stripping and pulses of large wood recruitment to the floodplain and channel. The widespread uprooting of trees follows hydrodynamic loading from floodwaters and the associated moments of these forces about the tree bases. A tree will uproot when the drag moment exceeds the anchorage resistance capacity. Alternatively, trunks will rupture when the tensile stresses caused by bending exceed the tensile strength of the outer trunk fibres. The likelihood and pattern of trees dislodging during floods on a subtropical river was investigated by developing a tree stability model. The modeling framework included development of a drag moment model and testing several potential formulations for anchorage resistance. Model parameters were calibrated to data collected in experiments and from observations in aerial photographs before and after a large flood in 2011. The prediction accuracy for the adopted tree stability model was 78%. Results from design flood simulations suggest that less than a third of the forest will dislodge even during the largest floods conceivable. This remarkable stability moderates the quantity of large wood recruited from riparian forests during extreme floods, which can impact infrastructure such as bridges and culverts downstream. Low rates of wood recruitment from dislodged floodplain trees in extreme floods suggests bank erosion is the dominant source of wood recruitment in these catchments. [ABSTRACT FROM AUTHOR]

Resilience is commonly addressed when dealing with the sustainable planning and management of social–ecological systems, but we lack a unified framework for its quantitative assessment and application. We present an operational resilience framework (ORF) based on recognizing and relating several elements: system variables (e.g., ecosystem services), disturbances and stressors acting at given spatiotemporal scales, a reference state, and metrics comparing the observed system variables to the reference state. These elements fit into a rationale aimed at identifying resilience predictors suitable to be managed and co-drivers which describe non-manageable context, reflecting the mechanisms involved in resilience. By a systematic search of the presence of the ORF concepts in 453 empirical studies assessing resilience, we corroborate that ORF can be applied to studies on forest social–ecological systems. This literature survey shows that ORF elements are commonly recognized, although the logical narrative relating them is not always explicit, particularly in socioeconomic-focused studies. We advocate that the proposed ORF allows to standardize the terminology and to frame and measure resilience, allowing sounder comparisons and better-supported recommendations for the improvement of resilience in social–ecological systems, particularly in forest systems. [ABSTRACT FROM AUTHOR]

This paper analyzes the static resilience of global wood forest products trade networks across upstream, midstream, downstream, and recycling sectors using a complex directed weighted network approach. By examining topological features and resilience from 2002 to 2021, this study reveals significant structural evolution and scale expansion in these networks. It finds improvements in network efficiency and resilience, alongside an increase in weighted hierarchy highlighting the prominent roles of core countries like China, the US, and Germany. While these countries bolster network resilience, they also introduce certain vulnerabilities. This study finds notable disassortative mixing without trade volume weights and diversified trends with weights, offering new insights into network dynamics. Core nodes must address disruption risks, enhance diversity, and establish emergency response mechanisms. In the recycling sector, this paper highlights weak trade connections and low resilience, with the US maintaining dominance, China's influence waning, and India's rapid ascent. This paper concludes by emphasizing the need for refined indicator systems and deeper explorations into resilience enhancement strategies for operational and targeted suggestions. [ABSTRACT FROM AUTHOR]

Here, we examine the effects of wildfires on the soil seed bank of a terra firme forest in the eastern Amazon. This seed bank is described via community-level attributes across forest stands exposed to wildfires once or twice, as well as across unburned, old-growth forest stands. A total of 2345 seeds germinated (837.5 seeds/m2). Across all three forest habitats, the soil seed bank was dominated by a small set of light-demanding species, with two to three species accounting for over 80% of all seeds. On the other hand, the seed bank of all habitats completely lacked seeds from the old-growth flora. Wildfires posed no effects relative to seed density and species richness. However, fire (1) reduced beta diversity, (2) caused an 8% increase in herb abundance and a 4% increase in the number of seeds produced by short-lived pioneers, and (3) resulted in a slight impact on taxonomic species composition. Our results suggest that the soil seed bank, while exhibiting high seed densities, is naturally species poor and, thus, relatively resistant to the first fire events. This implies that the recovery of fire-degraded forests will rely on vertebrate-dispersed seeds coming from any remaining well-preserved old-growth forest stands that are present in the landscape and are highly vulnerable to fire. [ABSTRACT FROM AUTHOR]

Mangroves can increase their elevation relative to tidal flooding through biogeomorphic feedbacks but can submerge if rates of sea-level rise are too great. There is an urgent need to understand the vulnerability of mangroves to sea-level rise so local communities and resource managers can implement and prioritize actions. The need is especially pressing for small islands, which have been identified as an area of concern by the IPCC. We developed a generalizable modeling framework for tidal wetlands (WARMER-3) that accounts for species interactions and the belowground processes that dictate soil elevation building relative to sea levels. The model was calibrated with extensive field datasets, including accretion rates derived from 29 soil cores, over 300 forest inventory plots, water level, and elevation. The model included five mangrove tree species and was applied across seven regions around the Pacific Island of Pohnpei, Federated States of Micronesia, where mangrove forest is a critical ecosystem that supports subsistence living for local communities. We explored mangrove resilience and carbon accumulation under six sea-level rise scenarios. We also conducted an analysis to determine the sea-level rise rate threshold above which mangroves would be lost. The results suggest that Pohnpei mangroves can build their elevations relative to low and moderate rates of sea-level rise to prevent submergence, with limited loss of mangrove area through 2150. Under higher sea-level rise rates, however, forest elevation decreased substantially relative to mean sea level and there was extensive loss of mangrove area by that year. Regarding mangrove community composition, for all sea-level rise scenarios, the model predicted a change to increasing relative abundance of flood tolerant species and decreasing relative abundance of high-elevation species, which started to being realized by 2100. Variation in sediment supply, water levels, and elevation capital led to differential vulnerability around the island. We identified a threshold for Pohnpei mangroves where if local sea-level rise rates exceed 7.8 ± 2.2 mm/year they are projected to eventually submerge and be lost. Our modeling framework is novel by addressing both species interactions and critical belowground processes to better understand potential tidal ecosystem responses to sea-level rise. [ABSTRACT FROM AUTHOR]

Ecosystem‐scale photosynthetic efficiency (EPE) is proposed as an effective indicator to quantify gross primary productivity (GPP), but how the coupling between EPE and GPP varies as vegetation resilience decreases has not been evaluated. Here, we quantified forest resilience with optimized Bayesian models. With the use of multisource satellite and modeling data, our study revealed that forests on the Loess Plateau and in the Qinba Mountains in China are experiencing rapid resilience loss and are already facing mortality warnings after 2010. Reductions in resilience also drove the marked decoupling of GPP from EPE. Notably, the decline in resilience was accompanied by a decrease in EPE in about 74% of the forests while GPP increased. The mechanism underlying this decoupling could be attributed to enhanced atmospheric water demand and soil water constraints. The dynamic relationships found here could help to improve forest mortality models and enhance photosynthesis‐based GPP evaluation. Plain Language Summary: The persistence and functionality of forest ecosystems highly depend on their resilience. Low‐resilience forests may be unable to absorb changes and achieve system variable stabilization under perturbations in external drivers and may undergo irreversible system shifts. Reduced resilience is often caused by impaired physiological functions, which inevitably affects forest photosynthetic processes and carbon sinks. Our study on fragile ecosystems in China revealed that forests are rapidly losing resilience and are already facing mortality warnings after 2010. This phenomenon has also led to significant decoupling of carbon sinks from photosynthesis, driven by an elevated atmospheric water demand and soil water deficits. These findings demonstrate that forests will exhibit greater risk of mortality across broad scales under global warming and that photosynthetic proxies cannot be consistently used for evaluating carbon sequestration in ecosystems. Key Points: Early mortality warning signals have been detected for different forest types since 2010A reduction in forest resilience weakens the relationship between the gross primary productivity and photosynthetic efficiencyThe decoupling of forest photosynthesis from carbon sinks exhibits different response patterns to soil water and atmospheric drying [ABSTRACT FROM AUTHOR]

Among the set of phenological traits featuring mangrove ecosystems, litterfall production stands out with marked intra-annual and longer-term variation. Furthermore, mangrove forests resilience is one of the most important ecological attribute, reconciling the juxtaposed terrestrial and marine environment such transitional systems occupy. However, world's mangroves are nowadays facing recurrent climatic events, reflected in anomalies depicted by major drivers, including temperature and precipitation. This physical-environmental setting may either constrain or favor overall forest productivity. A combination of time series analysis (spectral density and cross-correlation techniques) and statistical model fitting (General additive model) was implemented to explore trends in total litterfall of a well-developed mangrove forest in southeastern Gulf of Mexico (Celestun Lagoon, SE Mexico) and potential association with the varying behavior of temperature (°C) and precipitation (mm month-1), highlighting their anomalies. The results are consistent with a synchronous response between litterfall production and climatic variables (mean monthly temperature and total monthly precipitation). Concurrent peak litterfall production in Celestun lagoon with high temperatures and precipitation occurred during June and October, featuring a two-month time lag for the response time. More than half of the litterfall anomalies (53.5%) could be reflecting either multiple sources of climatic anomalies (maximum, minimum, and monthly average temperature and monthly total precipitation) or single point events (cyclone landfall). This relationship dynamics showed an interannual persistence (1999–2010). The structure portrayed by the litterfall time-series was not unequivocally related to climatic anomalies. Arguably, climatic anomalies behave with different intensities and even may exhibit complex interactions among them. The study of anomalies provides a baseline for a better grasp of: i) mangrove anomalies responses and ii) their vulnerability to these extremes. [ABSTRACT FROM AUTHOR]

Animals often rely on the presence of multiple, spatially segregated cover types to satisfy their ecological needs; the juxtaposition of these cover types is called landscape complementation. In ecosystems that have been homogenized because of human land use, such as fire‐suppressed forests, management activities have the potential to increase the heterogeneity of cover types and, therefore, landscape complementation. We modeled changes to California spotted owl (Strix occidentalis occidentalis) nesting/roosting habitat, foraging habitat and habitat co‐occurrence (i.e. landscape complementation) within a 971 245‐ha forest landscape restoration project area, the Tahoe‐Central Sierra Initiative (TCSI) landscape, through mid‐century as a function of fuels reduction, fire and climate change. Compared to a minimal management scenario, accelerated management within the TCSI landscape was predicted to increase the number of potential 400‐ha spotted owl territories containing a high degree of landscape complementation (defined as containing >20% nest/roost habitat and >20% foraging habitat) at lower elevations (<5000 ft.) by an average of 90 to 118 territories by 2050, depending on the climate scenario examined. At higher elevations (>5000 ft.), potential benefits of treatments to spotted owl nesting/roosting and foraging habitat were less evident, but accelerated management did not result in habitat loss. Our results suggest that accelerated fuels reduction and forest restoration treatments within this large landscape are expected to benefit spotted owls by improving the spatial juxtaposition of nesting/roosting and foraging cover types by 2050 compared to a minimal management scenario. Fuels reduction and forest restoration in this landscape thus can both increase the resilience of forest ecosystems to disturbances as well as benefit the habitat of a sensitive old‐forest species. [ABSTRACT FROM AUTHOR]

Background: The potential ecosystem collapse of forests in Mediterranean-type ecosystems (MTEs) by unprecedented droughts is worrisome due to the impacts on its exceptional biodiversity and human well-being. However, research integrating the impacts of global change drivers, forest resilience and the challenges facing human-nature relationships is still scarce. Methods and results: Using the central Chile megadrought and recently massive forest browning event as a model scenario, we identified, through a scientific literature review and an interdisciplinary scientific workshop, the research priorities and questions to address for MTEs in a context of global change. Our results highlighted knowledge gaps that need to be covered, particularly in social and environmental sciences, with an emphasis on soil science. Research priorities must focus on (1) the understanding of interactive effects of global and local anthropogenic drivers on MTEs and (2) the evaluation of the potential impacts of MTEs collapse on human well-being and ecosystem functioning. Conclusions: We highlight the need for a collaborative approach involving scientists, landowners, managers/administrators, and policymakers to apply adaptive forest management against the current socio-environmental challenges under a global change context. [ABSTRACT FROM AUTHOR]

The world is currently facing uncertainty caused by environmental, social, and economic changes and by political shocks. Fostering social-ecological resilience by enhancing forests' ability to provide a range of ecosystem services, including carbon sequestration, habitat provision, and sustainable livelihoods, is key to addressing such uncertainty. However, policy makers and managers currently lack a clear understanding of how to operationalise the shaping of resilience through the combined challenges of climate change, the biodiversity crisis, and changes in societal demand. Based on a scientific literature review, we identified a set of actions related to ecosystem services, biodiversity conservation, and disturbance and pressure impacts that forest managers and policy makers should attend to enhance the resilience of European forest systems. We conclude that the resilience shaping of forests should (1) adopt an operational approach, which is currently lacking, (2) identify and address existing and future trade-offs while reinforcing win–wins and (3) attend to local particularities through an adaptive management approach. [ABSTRACT FROM AUTHOR]

Tree regeneration shapes forest carbon dynamics by determining long‐term forest composition and structure, which suggests that threats to natural regeneration may diminish the capacity of forests to replace live tree carbon transferred to the atmosphere or other pools through tree mortality. Yet, the potential implications of tree regeneration patterns for future carbon dynamics have been sparsely studied. We used forest inventory plots to investigate whether the composition of existing tree regeneration is consistent with aboveground carbon stock loss, replacement, or gain for forests across the northeastern and midwestern USA, leveraging a recently developed method to predict the likelihood of sapling recruitment from seedling abundance tallied within six seedling height classes. A comparison of carbon stock predictions from tree and seedling composition suggested that 29% of plots were poised to lose carbon based on seedling composition, 55% were poised for replacement of carbon stocks (<5 Mg ha−1 difference) and 16% were poised to gain carbon. Forests predicted to lose carbon tended to be on steeper slopes, at lower latitudes, and in rolling upland environments. Although plots predicted to gain and lose carbon had similar stand ages, carbon loss plots had greater current carbon stocks. Synthesis and applications. Our results demonstrate the utility of considering tree regeneration through the lens of carbon replacement to develop effective management strategies to secure long‐term carbon storage and resilience in the context of global change. Forests poised to lose C due to climate change and other stressors could be prioritized for regeneration strategies that enhance long‐term carbon resilience and stewardship. [ABSTRACT FROM AUTHOR]

Enhancing forest drought resilience is important for preserving ecosystem services in the face of climate change, but operational management methods for boreal forests aiming to preserve ecosystem services under drought are still largely missing. This study explores the use of satellite remote sensing to monitor vegetation stress phases related to drought progression and to quantify both short- and long-term impacts on forest growth. Data from the Sentinel-2 satellite mission were used to calculate the response of vegetation indices across six forest types, using the time period from 2015 to 2017 as a reference dataset. The percentual difference between the drought year of 2018 and the reference period was used to represent disturbance intensity and the system's capability to resist it. Additionally, the recovery time was taken into consideration. Breakpoint detection with daily temporal resolution was used to quantify the response time of each forest type in relation to the onset date of meteorological drought. Results indicate that Sentinel-2 data can be used to monitor vegetation stress associated with drought progression and estimate the characteristics of forest resilience. High temporal resolution observations should be prioritized over annual maximum vegetation index values to determine the intensity of disturbance. Consistent severe impacts were observed in areas with limited soil moisture availability. The recovery time of forests took up to 4 years. Drought exposure during consecutive years could be especially damaging for species requiring a longer recovery time than a single growing season. Sentinel-2-based monitoring approach could benefit decision-support systems for forest management aiming to enhance drought resilience. [ABSTRACT FROM AUTHOR]

Decades of industrial-scale logging have damaged the structure, function, and composition of Australia's forests; increased the threat from severe fires; and generated social distrust – all in a disrupted climate regime. As state agencies withdraw from logging, restoration of forest resilience becomes paramount. We critique two recent proposals for 'commercial timber operations' in two Australian states that have recently 'ceased logging native forests': (1) wind-throw removal via 'community forestry' in Victoria; and (2) 'ecological thinning' in Western Australia. Analysis suggests that ecological restoration will require: (1) scientifically valid and reliable projects; (2) integration across knowledge systems; (3) full cost-benefit accounting; (4) repair of forest legacy damage; (5) restoration of environmental resilience; (6) control of environmental weeds, pests and pathogens; (7) enhanced capacity for early detection of, and rapid response to disturbance; (8) generation of trust to enable a social licence; (9) fostering integrity in media and public relations; and (10) appropriate categorisation in land use. Neither case study demonstrate the application of these forest restoration principles nor provides a way to evaluate the effectiveness of the proposals. These case studies continue the resource-led exploitation of post-production forests, exacerbating damage through the continued depletion of the natural assets essential to generating resilience. Moving beyond resource-led to environment-led management is necessary to restore the ecological integrity of these forests. A shift from the resource-led focus to an environment-led focus guided by scientifically validated principles is likely to also require new administrative and governance arrangements for these forests. Two case studies of 'ecological forestry' ('community forestry' in Victoria, and 'ecological thinning' in Western Australia) demonstrate the urgency to transition from resource-led to environment-led management in the restoration of post-production forests. [ABSTRACT FROM AUTHOR]

Climate change has profound impacts on forest ecosystem dynamics and could lead to the emergence of novel ecosystems via changes in species composition, forest structure, and potentially a complete loss of tree cover. Disturbances fundamentally shape those dynamics: the prevailing disturbance regime of a region determines the inherent variability of a system, and its climate‐mediated change could accelerate forest transformation. We used the individual‐based forest landscape and disturbance model iLand to investigate the resilience of three protected temperate forest landscapes on three continents—selected to represent a gradient from low to high disturbance activity—to changing climate and disturbance regimes. In scenarios of sustained strong global warming, natural disturbances increased across all landscapes regardless of projected changes in precipitation (up to a sevenfold increase in disturbance rate over the 180‐year simulation period). Forests in landscapes with historically high disturbance activity had a higher chance of remaining resilient in the future, retaining their structure and composition within the range of variability inherent to the system. However, the risk of regime shift and forest loss was also highest in these systems, suggesting forests may be vulnerable to abrupt change beyond a threshold of increasing disturbance activity. Resilience generally decreased with increasing severity of climate change. Novelty in tree species composition was more common than novelty in forest structure, especially under dry climate scenarios. Forests close to the upper tree line experienced high novelty in structure across all three study systems. Our results highlight common patterns and processes of forest change, while also underlining the diverse and context‐specific responses of temperate forest landscapes to climate change. Understanding past and future disturbance regimes can anticipate the magnitude and direction of forest change. Yet, even across a broad gradient of disturbance activity, we conclude that climate change mitigation is the most effective means of maintaining forest resilience. [ABSTRACT FROM AUTHOR]

Background and Aims Lianas have higher relative abundance and biomass in drier seasonal forests than in rainforests, but whether this difference is associated with their hydraulic strategies is unclear. Here, we investigate whether lianas of seasonally dry forests are safer and more efficient in water transport than rainforest lianas, explaining patterns of liana abundance. Methods We measured hydraulic traits on five pairs of congeneric lianas of the tribe Bignonieae in two contrasting forest sites: the wet 'Dense Ombrophilous Forest' in Central Amazonia (~2 dry months) and the drier 'Semideciduous Seasonal Forest' in the inland Atlantic Forest (~6 dry months). We also gathered a broader database, including 197 trees and 58 liana species from different tropical forests, to compare hydraulic safety between habits and forest types. Key Results Bignonieae lianas from both forests had high and similar hydraulic efficiency but exhibited variability in resistance to embolism across forest types when phylogenetic relationships were taken into account. Three genera had higher hydraulic safety in the seasonal forest than in the rainforest, but species across both forests had similar positive hydraulic safety margins despite lower predawn water potential values of seasonal forest lianas. We did not find the safety–efficiency trade-off. Merging our results with previously published data revealed a high variability of resistance to embolism in both trees and lianas, independent of forest types. Conclusions The high hydraulic efficiency of lianas detected here probably favours their rapid growth across tropical forests, but differences in hydraulic safety highlight that some species are highly vulnerable and may rely on other mechanisms to cope with drought. Future research on the lethal dehydration threshold and the connection between hydraulic resistance strategies and liana abundance could offer further insights into tropical forest dynamics under climatic threats. [ABSTRACT FROM AUTHOR]

Background: Tree ontogeny is the genetic trajectories of regenerative processes in trees, repeating in time and space, including both development and reproduction. Understanding the principles of tree ontogeny is a key priority in emulating natural ecological patterns and processes that fall within the calls for closer-to-nature forest management. By recognizing and respecting the growth and development of individual trees and forest stands, forest managers can implement strategies that align with the inherent dynamics of forest ecosystem. Therefore, this study aims to determine the ontogenetic characteristics of tree regeneration and growth in northern European hemiboreal forests. Methodology: We applied a three-step process to review i) the ontogenetic characteristics of forest trees, ii) ontogenetic strategies of trees for stand-forming species, and iii) summarise the review findings of points i and ii to propose a conceptual framework for transitioning towards closer-to-nature management of hemiboreal forest trees. To achieve this, we applied the super-organism approach to forest development as a holistic progression towards the establishment of natural stand forming ecosystems. Results: The review showed multiple aspects; first, there are unique growth and development characteristics of individual trees at the pre-generative and generative stages of ontogenesis under full and minimal light conditions. Second, there are four main modes of tree establishment, growth and development related to the light requirements of trees; they were described as ontogenetic strategies of stand-forming tree species: gap colonisers, gap successors, gap fillers and gap competitors. Third, the summary of our analysis of the ontogenetic characteristics of tree regeneration and growth in northern European hemiboreal forests shows that stand-forming species occupy multiple niche positions relative to forest dynamics modes. Conclusions: This study demonstrates the importance of understanding tree ontogeny under the pretext of closer-to-nature forest management, and its potential towards formulating sustainable forest management that emulates the natural dynamics of forest structure. We suggest that scientists and foresters can adapt closer-to-nature management strategies, such as assisted natural regeneration of trees, to improve the vitality of tree communities and overall forest health. The presented approach prioritizes ecological integrity and forest resilience, promoting assisted natural regeneration, and fostering adaptability and connectivity among plant populations in hemiboreal tree communities. [ABSTRACT FROM AUTHOR]

Assessing the dynamics of forest structure complexity is a critical task in times of global warming, biodiversity loss and increasing disturbances in order to ensure the resilience of forests. Recent studies on forest biodiversity and forest structure emphasize the essential functions of deadwood accumulation and diversification of light conditions for the enhancement of structural complexity. The implementation of an experimental patch‐network in managed broad‐leaved forests within Germany enables the standardized analysis of various aggregated and distributed treatments characterized through diverse deadwood and light structures. To monitor the dynamics of enhanced forest structure complexity as seasonal and trend components, dense time‐series from high spatial resolution imagery of Sentinel‐1 (Synthetic‐Aperture Radar, SAR) and Sentinel‐2 (multispectral) are analyzed in time‐series decomposition models (BEAST, Bayesian Estimator of Abrupt change, Seasonal change and Trend). Based on several spatial statistics and a comprehensive catalog on spectral indices, metrics from Sentinel‐1 (n = 84) and Sentinel‐2 (n = 903) are calculated at patch‐level. Metrics best identifying the treatment implementation event are assessed by change point dates and probability scores. Heterogeneity metrics of Sentinel‐1 VH and Sentinel‐2 NMDI (Normalized Multi‐band Drought Index) capture the treatment implementation event most accurately, with clear advantages for the identification of aggregated treatments. In addition, aggregated structures of downed or no deadwood can be characterized, as well as more complex standing structures, such as snags or habitat trees. To conclude, dense time‐series of complementary high spatial resolution sensors have the potential to assess various aggregated forest structure complexities, thus supporting the continuous monitoring of forest habitats and functioning over time. [ABSTRACT FROM AUTHOR]

The natural resilience of the forests to face impacts of blowdown damages was affected by harvesting operations. Variable retention harvesting (VRH) increases forest structure heterogeneity in managed stands and decreases blowdown damages. The objective of this study was to characterize blowdown in Nothofagus pumilio forests managed with VRH in Southern Patagonia (Argentina). We analyzed long-term plots and one area affected by a windstorm after harvesting (exposure to winds and influence of retention patches) using univariate analyses. We found a differential impact in retention patches compared to dispersed retention after a windstorm considering aspect and distance to edge (e.g., blowdown trees: F = 6.64, p < 0.001). The aspect in retention patches presented few structural differences before the windstorm (e.g., tree diameter: F = 3.92, p = 0.014) but was not greatly influenced by the received damage after the windstorm. In long-term plots, we found that aspect and location in patches (distance to edge) determined the tree stability. We also found differences in wind damage considering retention level and design (e.g., aggregates and dispersed retention vs. aggregates and clear-cuts). We conclude that VRH increased the heterogeneity in harvested areas, where retention patches presented greater resilience in confronting extreme climate events and decreased recurrent wind exposure impacts in the long term. We found the marginal influence of aspect in the retention patches despite dominant winds and damages received by remnant trees during harvesting. [ABSTRACT FROM AUTHOR]

Optimising the interaction between society and the environment is one of the fundamental directions of recreational forest management. To improve the efficiency of using ecosystem services of recreational and health-improving forests, there is a need to develop new approaches and tools for management decision-making, a key component of which is the assessment of these beneficial goods. The aim of the study is to analyse public opinion regarding the expressed and identified preferences for the characteristics of recreational forests and recreational facilities, as well as to assess the willingness to pay for preferred forest characteristics and the maintenance of recreational facilities in proper condition. The study was conducted from June to August 2022 using a direct and anonymous online survey. It was found that respondents are willing to pay an average of 1-100 UAH/year to create and maintain the preferred characteristics of the forest and 101-500 UAH/year to create and maintain recreational facilities. As for the respondents' perception of forest characteristics that affect the choice of a place to relax, preference is given to mixed forests (74.8%), in which three tree species grow (57.9%), and forests up to 20 meters high (40.2%). On the other hand, only 15.9% of respondents preferred forests taller than 20 meters. The presence of deadwood in the forest is positively perceived by 51.4% of respondents, and 10.3% do not pay attention to the presence or absence of standing dead and drying up trees in the forest. The most important needs for which respondents visit recreational forests were walks, family recreation, and observing forest landscapes. The integration of the identified perceptions and preferences regarding recreational forests and objects into innovative decision-making in the field of forestry ensures a synergy of benefits, such as increasing the attractiveness of recreational forests and forest landscapes, increasing the resilience of forests to climate change, and meeting the local demand for wood biomass. [ABSTRACT FROM AUTHOR]

This study examines the structural dynamics and species composition of the "Ravna Vala" old-growth forest on Bjelašnica Mountain, focusing on neighborhood effects on tree growth. Data from a permanent 1-hectare plot, measured 2012 and 2023, revealed that silver fir (Abies alba Mill.) constitutes nearly 73% of the total volume, while beech (Fagus sylvatica L.) dominates in tree numbers. The forest displays a reverse J-curve pattern, with significant mortality in smaller diameter classes. Using indices for species intermingling, aggregation, and competition, the study found that diameter at breast height (dbh) and the aggregation index significantly influenced growth, especially for silver fir and beech. Additional factors like the mixing index and competition index were significant for beech growth. These results underscore the complexity of species interactions and the importance of tailored management strategies. Future research should explore factors limiting fir regeneration and the link between disturbances and beech recruitment. Management practices that mimic natural disturbances, such as creating larger gaps, are recommended to enhance species diversity and forest resilience. [ABSTRACT FROM AUTHOR]

Capturing the effects of fragmentation and ongoing changing climate on the population dynamics of long‐lived trees requires long‐term datasets, but these are uncommon in rainforests and dry forests outside of the tropics.This study capitalised on nine 0.04‐ha permanent plots established in 1982 within corridors of old‐growth subtropical dry forest (Araucarian vine forest) retained as fire breaks within forestry plantations in Imbil (southern Queensland, Australia). Tree diameter growth and survival were censused in 1997 and 2021, resulting in two monitoring periods.The most recent period was associated with an increasing trend in vapour pressure deficit (VPD). Consistent with this trend, we found that survival was substantially lower across all size classes in the second period.Mortality‐induced reductions in stem density were associated with faster growth rates in all but the largest stems in the second period. Growth was also moderately faster in plots near forest edges in the second period.The richness of obligate understory species declined significantly by an average of 1.44 species over the 40‐year study period.Synthesis and applications: Overall, our results are consistent with increasing tree mortality rates reported recently for the Australian wet tropics and suggest widespread and alarming impacts of increasing VPD on rainforest and dry forest community dynamics. To increase forest resilience in a changing climate, we recommend the retention of a buffer of plantation trees adjacent to old‐growth forest corridors; widening the forest corridors using faster‐growing species identified in this study and maintaining connections between scrub breaks and larger tracts of forest for species dispersal. [ABSTRACT FROM AUTHOR]

Forests provide essential ecosystem services that range from the production of timber to the mitigation of natural hazards. Rapid environmental changes, such as climate warming or the intensification of disturbance regimes, threaten forests and endanger forest ecosystem services. In light of these challenges, it is essential to understand forests' demographic processes of regeneration, growth, and mortality and their relationship with environmental conditions. Specifically, understanding the regeneration process in present‐day forests is crucial since it lays the foundation for the structure of future forests and their tree species composition. We used Swiss National Forest Inventory (NFI) data covering vast bio‐geographic gradients over four decades to achieve this understanding. Trees that reached a diameter at breast height of 12 cm between two consecutive NFI campaigns were used to determine regeneration and were referred to as ingrowth. Employing three independent statistical models, we investigated the number, species, and diameter of these ingrowth trees. The models were subsequently implemented into a forest simulator to project the development of Swiss forests until the mid‐21st century. The simulation results showed an ingrowth decrease and a shift in its species composition, marked by a significant reduction in Norway spruce Picea abies and concurrent increases in broadleaves. Nevertheless, the pace of this change towards climatically better adapted species composition is relatively slow and is likely to slow down even further as ingrowth declines in the future, in contrast to the fast‐changing climatic conditions. Hence, support through adaptive planting strategies should be tested in case ingrowth does not ensure the resilience of forests in the future. We conclude that since the regeneration of forests is becoming increasingly challenging, the current level at which ecosystem services are provided might not be ensured in the coming decades. [ABSTRACT FROM AUTHOR]

Climate change threatens the very existence of the world's forests as temperature increases outpace forests' ability to adapt. Society must implement adaptation policies aimed at making forests more resilient. This Article describes how we can better manage for more resilient forests by first detailing some of the scientific and policy complexity affecting our ability to do so. The Article then details the primary adaptation solutions for creating greater forest resiliency (reducing fire risk and integrating more climate resilient species into forests), some of the impediments to implementing those solutions (federalism, geographic and ecological differences in forests, and scientific unknowns), and how to overcome those impediments (incentivizing market development, increasing government investment, reforming federal administrative law, and harnessing expertise in regional forestry programs to build trust). [ABSTRACT FROM AUTHOR]

Wildfire risk is growing in the forested portion of the Wildland-Urban Interface, especially in the Western United States. Some commentators have suggested that the time has come for measures that would reduce the human presence in this area. In certain circumstances, however, family forestland owners have a salutary effect on forest resiliency. The attempt to exclude family forestland owners would create more problems than it would solve. A better strategy would be to assist family forestland owners in fireproofing their residences and improving the health of their forests. [ABSTRACT FROM AUTHOR]

Understanding fire and large herbivore interactions in interior western forests is critical, owing to the extensive and widespread co‐occurrence of these two disturbance types and multiple present and future implications for forest resilience, conservation and restoration. However, manipulative studies focused on interactions and outcomes associated with these two disturbances are rare in forested rangelands. We investigated understory vegetation response to 5‐year spring and fall prescribed fire and domestic cattle grazing exclusion in ponderosa pine stands and reported long‐term responses, almost two decades after the first entry fires. In fall burn areas open to cattle grazing, total understory cover prior to utilization was about 12% lower compared with fall burn areas where cattle were experimentally excluded. This response was not strongly driven by a particular palatable or unpalatable plant functional group. Fire and grazing are likely interacting in a numerically mediated process, as we found little evidence to support a functionally moderated pathway. Post‐fire green‐up may equalize forage to a certain extent and concentrate herbivores in the smaller burned areas within pastures, constraining a positive understory response to burning. Fall fire and grazing also increased annual forbs and resprouting shrubs. The effects of spring burning were relatively minor, and we found no interaction with grazing. The nonnative annual grass Bromus tectorum (cheatgrass) remains a problematic invader linked to fall burning but not grazing in stands that had higher propagule pressure when the experiment was initiated. At these sites, exotic grass was a major component of the vegetation by 2015, and invasion was also increasing in spring burn and unburned areas. Information from our study suggests that frequent fall fires and cattle grazing combined may reduce understory resilience in similar dry ponderosa pine forests. Consideration of longer fire return intervals, resting areas after fire, virtual fencing, or burning entire pastures may help to mitigate the effects noted in this study. [ABSTRACT FROM AUTHOR]

The Amazon rainforest (ARF) is threatened by deforestation and climate change, which could trigger a regime shift to a savanna‐like state. Whilst previous work has suggested that forest resilience has declined in recent decades, that work was based only on local resilience indicators, and moreover was potentially biased by the employed multi‐sensor and optical satellite data and undetected anthropogenic land‐use change. Here, we show that the average correlation between neighboring grid cells' vegetation time series, which is referred to as spatial correlation, provides a more robust resilience indicator than local estimations. We employ it to measure resilience changes in the ARF, based on single‐sensor Vegetation Optical Depth data under conservative exclusion of human activity. Our results show an overall loss of resilience until around 2019, which is especially pronounced in the southwestern and northern Amazon for the time period from 2002 to 2011. The results from the reliable spatial correlation indicator suggest that in particular the southwest of the ARF has experienced pronounced resilience loss over the last two decades. Plain Language Summary: The Amazon rainforest (ARF) is Earth's most biodiverse ecosystem, crucial for regulating global and regional climate through water recycling and carbon uptake. Several studies suggest that ongoing deforestation, land‐use changes, and climate change induced shifts in rainfall patterns could trigger an abrupt regime shift from the current rainforest to a low‐treecover state. Here, we investigate the resilience of the ARF vegetation based on remotely sensed Vegetation Optical Depth, particularly useful in high‐biomass areas such as the ARF. The main feedback mechanism, essential for potential tipping, is moisture recycling. The trade winds bring in moisture from the Atlantic Ocean to South America's east, where it precipitates. Much of this moisture re‐enters the atmosphere via evapo‐transpiration and is transported further west, thereby establishing a moisture regime supporting the rainforest. The induced spatial coupling results in the spatial correlation being a reliable indicator of resilience. We compare changes in the spatial correlation to changes in the two classic indicators. The greatest resilience loss is detected in the southwestern Amazon, which has been identified as a highly‐coupled sub‐system since it is reliant on recycled moisture from upstream the trade winds, hence making the spatial correlation a particularly suitable and trustworthy resilience indicator there. Key Points: We quantify changes in Amazon resilience by investigating satellite data that has been carefully selected to avoid known sources of biasSpatial correlation of vegetation time series reliably shows resilience changes in spatially coupled systems such as the Amazon RainforestThe Amazon forest is losing resilience, especially in the southwestern Amazon, a region which has high demand on recycled moisture [ABSTRACT FROM AUTHOR]

Non-structural carbohydrate (NSC) reserves constitute the critical cornerstone of forest resilience to adversity and post-disaster recovery. Planting densities and configurations affect the growth and physiological processes of trees and are essential to investigate the effects of planting densities and configurations on the storage and allocation of NSC in trees for afforestation strategies. We investigated the seasonal dynamics of NSC in various organs (leaves, branches, stems, coarse roots, and fine roots) of Populus sp. in a stand density experiment located on the western bank of Hongze Lake, Jiangsu, China to assess the whole-tree carbon budget. We used a nested sampling design of stands with density as the first factor, which included two levels [400 vs. 277 stems per hectare (sph)], and spacing configuration (square vs. rectangular) as the nested factor. Our results indicated that the seasonal characteristics of NSC in poplar were obvious, with NSC in storage organs being consumed for growth from March to May and gradually accumulating after July, peaking in November, with the highest fluctuations in branches and stems. The NSC pool was dominated by starch (72.73 ± 4.28%), and the stems (65.49 ± 5.43%) contributed more than half of the whole-tree starch pool, and the branches were the largest sugar pool (39.88 ± 8.36%). The seasonal patterns in poplar NSC were similar across different planting densities and configurations, whereas the NSC pool size varied significantly across configurations. Low planting density (277 sph) with square configuration increases NSC storage to optimum levels at the individual and stand scales. A square configuration with low intraspecific competition might be an optimal afforestation practice to enhance carbon sequestration in poplar plantations located in temperate monsoon climates. [ABSTRACT FROM AUTHOR]

Droughts can affect forest ecosystems and lead to soil degradation, biodiversity loss, and desertification. Not all regions of Mexico are affected in the same way, as some areas are naturally more prone to drought due to their geographical location. Therefore, the objective of this work was to carry out a spatio-temporal analysis of the occurrence of droughts (severe and extreme) in Mexican forest systems, covering the period 2000–2021, and to study the area covered by these events in Mexican forest systems. This analysis was divided into three stages: the classification of land use and vegetation, spatial mapping and the classification of drought intensity, and an analysis of drought frequency and probability in forest systems. The results show that more than 46% of Mexico's forest area experienced severe and extreme droughts during the 21-year period studied. Broadleaved forests were most affected by severe and extreme droughts, with a frequency of 6 years. The increasing frequency of droughts poses a major challenge to the resilience of forest ecosystems in Mexico, highlighting the need to implement climate change adaptation and forest management measures to protect the country's biodiversity and natural resources. [ABSTRACT FROM AUTHOR]

This study examines the recovery of late-successional forests in the Acadian Forest Region of northeastern North America after anthropogenic canopy disturbance. Tree species were sampled in a chronosequence of post-clearcut (3–54 years) and remnant late-successional forests (100–165 years) in four demographic size classes in Nova Scotia, Canada: seedlings, small saplings, large saplings, and canopy trees. Clearcut forests acquired late-successional canopy species composition within five decades after logging disturbance. Resilience to clearcutting was due principally to the persistence of residual shade-tolerant coniferous species, mostly red spruce (Picea rubens Sarg.) and eastern hemlock (Tsuga canadensis (L.) Carrière) in recovering stands. Redundancy analysis (RDA) revealed that most residual canopy species responded positively to canopy removal as small saplings, but not as seedlings. Seedlings of all residual canopy species exhibited strong associations with stand age, canopy cover, and microhabitats characteristic of older forests, such as rotting logs and smaller pieces of decayed wood. These results show that managed late-successional Acadian forests can recover quickly after clearcutting if advance tree regeneration (seedlings and saplings) is present and protected in the understory during canopy removal. Such Careful Logging methods focused on advance regeneration remain under-utilized in Acadian forests, though our results indicate they could better address silvicultural objectives such as maintaining a viable conifer component throughout stand development, as well as broader biodiversity goals in the management of late-successional forest types. [ABSTRACT FROM AUTHOR]

The timing, location, intensity, and drivers of forest disturbance and recovery are crucial for developing effective management strategies and policies for forest conservation and ecosystem resilience. Although many algorithms and improvement methods have been developed, it is still difficult to guarantee the detection accuracy for forest disturbance and recovery patterns in southern China due to the complex climate and topography, faster forest recovery after disturbance, and the low availability of noise-free Landsat images. Here, we improved the LandTrendr parameters for different provinces to detect forest disturbances and recovery trajectories based on the LandTrendr change detection algorithm and time-series Landsat images on the GEE platform, and then applied the secondary random forest classifier to classify the forest disturbance and recovery patterns in southern China during 1990–2020. The accuracy evaluation indicated that our approach and improved parameters of the LandTrendr algorithm can increase the detection accuracy for both the spatiotemporal patterns and multiple events of forest disturbance and recovery, with an overall accuracy greater than 86% and a Kappa coefficient greater than 0.91 for different provinces. The total forest loss area was 1.54 × 105 km2 during 1990–2020 (4931 km2/year); however, most of these disturbed forests were recovered and only 6.39 × 104 km2 was a net loss area (converted to other land cover types). The area with two or more times of disturbance events accounted for 11.50% of the total forest loss area. The total forest gain area (including gain after loss and the afforestation area) was 5.44 × 105 km2, among which, the forest gain area after loss was 8.94 × 104 km2, and the net gain area from afforestation was 4.55 × 105 km2. The timing of the implementation of forestry policies significantly affected the interannual variations in forest disturbance and recovery, with large variations among different provinces. The detected forest loss and gain area was further compared against with inventory and other geospatial products, and proved the effectiveness of our method. Our study suggests that parameter optimization in the LandTrendr algorithm could greatly increase the accuracy for detecting the multiple and lower rate disturbance/recovery events in the fast-regrowing forested areas. Our findings also offer a long-term, moderate spatial resolution, and precise forest dynamic data for achieving sustainable forest management and the carbon neutrality goal in southern China. [ABSTRACT FROM AUTHOR]

Climate change-induced hazards, such as drought, threaten forest resilience, particularly in vulnerable regions such as the Mediterranean Basin. Maritime pine (Pinus pinaster Aiton), a model species in Western Europe, plays a crucial role in the Mediterranean forest due to its genetic diversity and ecological plasticity. This study characterizes transcriptional profiles of scion and rootstock stems of four P. pinaster graft combinations grown under well-watered conditions. Our grafting scheme combined drought-sensitive and drought-tolerant genotypes for scions (GAL1056: drought-sensitive scion; and Oria6: drought-tolerant scion) and rootstocks (R1S: drought-sensitive rootstock; and R18T: drought-tolerant rootstock). Transcriptomic analysis revealed expression patterns shaped by genotype provenance and graft combination. The accumulation of differentially expressed genes (DEGs) encoding proteins, involved in defense mechanisms and pathogen recognition, was higher in drought-sensitive scion stems and also increased when grafted onto drought-sensitive rootstocks. DEGs involved in drought tolerance mechanisms were identified in drought-tolerant genotypes as well as in drought-sensitive scions grafted onto drought-tolerant rootstocks, suggesting their establishment prior to drought. These mechanisms were associated with ABA metabolism and signaling. They were also involved in the activation of the ROS-scavenging pathways, which included the regulation of flavonoid and terpenoid metabolisms. Our results reveal DEGs potentially associated with the conifer response to drought and point out differences in drought tolerance strategies. These findings suggest genetic trade-offs between pine growth and defense, which could be relevant in selecting more drought-tolerant Pinus pinaster trees. [ABSTRACT FROM AUTHOR]