Forest Ecology and Management

1) BackgroundUnderstanding how caterpillar communities vary within tree canopies is key to interpreting forest trophic dynamics and responses to environmental change, yet such variation remains poorly quantified due to the challenges of sampling in three dimensions. 2) AimsWe quantified within-canopy heterogeneity in caterpillar densities, diversity, and herbivory and explored relationships with host tree phenology and commonly used ground-based monitoring approaches. 3) MethodsUsing direct canopy access, we sampled branches from lower, middle, and upper canopy strata of 34 mature pedunculate oaks (Quercus robur) in Wytham Woods, UK, during the spring abundance peak over three consecutive years (2023-2025). We tested for vertical stratification in caterpillar community metrics, examined patterns in early instar distributions at emergence, assessed associations with host tree phenology across spatiotemporal scales, and evaluated how well ground-based methods (water and frass traps) reflect canopy communities. 4) ResultsVertical stratification was modest but varied among years: densities and species richness increased with canopy height in 2023, decreased in 2024, and were uniformly low across strata in 2025. Although within-crown budburst timing varied systematically, with upper branches bursting approximately two days earlier than lower branches, tree phenology did not explain within- or between-year variation in caterpillar communities. Frass trap data correlated moderately well with canopy caterpillar densities, whereas water traps showed weaker and less consistent relationships, reflecting behavioural and methodological biases. 5) ConclusionsCaterpillar communities showed no consistent patterns of vertical stratification across years, instead they are shaped more strongly by inter-annual and tree-level variation. Integrating targeted canopy sampling with scalable ground-based proxies could greatly improve monitoring of arboreal Lepidoptera and inform studies of trophic synchrony and wood-land resilience under environmental change.

O_LIThe global decline of natural forests is accompanied by a rapid expansion of commercial tree plantations, which are expected to further increase to meet growing demand for wood products. However, planted forests generally support lower biodiversity than natural forests, particularly when monospecific and intensively managed. In this context, broadleaved hedgerows have been proposed as a nature-based solution to enhance biodiversity within conifer-dominated plantation landscapes. Such features may be especially beneficial for small mammals, including rodents and shrews, which are key contributors to forest ecosystem functioning. However, their effects on small mammal communities remain largely unquantified. C_LIO_LIHere, we assessed variation in small mammal communities among habitat types within a native pine plantation-dominated landscape in southwestern France. Using a multi-year, multi-season survey, we compared species richness and abundance among plantation edges, broadleaved hedgerows embedded within plantations and natural broadleaved forests. We further tested whether environmental descriptors of hedgerow sites influenced dominant species and whether seasonal and interannual demographic dynamics modified habitat-related patterns. C_LIO_LIPine plantation edges and broadleaved hedgerows supported lower small mammal species richness than natural broadleaved forests and were dominated by two habitat generalists, Apodemus sylvaticus and Crocidura russula. This pattern was driven by the near absence of the forest specialist Clethrionomys glareolus. Hedgerows did not increase species richness relative to plantations, but provided favourable habitat for A. sylvaticus, which was scarce in pine plantation, while supporting fewer C. russula. Variation in hedgerow structure and composition further influenced A. sylvaticus abundance, while seasonal and interannual rodent population dynamics modulated habitat-related differences. C_LIO_LIOur results indicate that intensively managed pine plantations act as environmental filters, excluding forest-associated small mammals. While broadleaved hedgerows benefited one species, their capacity to restore forest-specialist communities was limited without broader landscape-scale interventions. These findings highlight both the ecological benefits and constraints of edge-based habitat interventions and provide guidance for designing and evaluating biodiversity-oriented management in plantation landscapes. C_LI

To adapt Mediterranean forests to increasingly harsh climatic conditions by promoting genetic diversity, thinning is often considered an effective strategy to enhance sexual regeneration. However, determining an optimal thinning level that both increases light availability and maintains favorable microclimatic conditions for germination, without excessively promoting herbaceous competition, remains challenging. To better understand how abiotic and biotic factors influence oak seedling development and to help identify a balanced thinning level under climate change, we conducted a semi-controlled experiment testing the combined effects of competition with a grass species (Poaceae), two canopy opening levels, and water stress. Our results highlight the crucial role of competition with Poaceae species - in our case Festuca ovina - in oak regeneration. Their presence not only intensifies competition for essential resources, but also modifies soil properties and alters belowground interactions, overall creating conditions less favorable for oak seedling establishment. In addition, our results highlight the significant impact of key abiotic factors that are canopy opening (which influences light availability) and hydric conditions, as well as their interactions with the effects of competition. We observed a consistent need for adequate light to ensure optimal seedling performance, suggesting that successful regeneration depends on balancing sufficient canopy opening to improve light availability with maintaining sufficient cover to mitigate water stress and limit grass competition. Overall, our study contributes to the broader debate on sustainable forest management strategies under changing climatic conditions.

O_LIRising anthropogenic pressures in the 20th century have caused extensive habitat loss and fragmentation, threatening biodiversity across ecosystems worldwide. In the boreal forest of Fennoscandia, clear-cut forestry has been a major driver of these changes, resulting in a fragmented landscape of even-aged forest stands. Several studies in recent years have investigated the effect of habitat fragmentation and loss on fungal communities associated with deadwood, but these have mainly focused on visible sporocarps and mushrooms. The effects of forestry on the whole fungal community within deadwood have not been explored as extensively, and especially not in the context of long-term effects. C_LIO_LIWe investigated the effects of clear-cutting on deadwood-inhabiting fungi in boreal Picea abies forests in Norway using ITS2 metabarcoding of sawdust samples collected from 459 logs distributed across 24 paired near-natural and previously clear-cut plots harvested 50 to 90 years ago. C_LIO_LIWhile the overall fungal richness associated with deadwood was similar between the two management types, community composition differed markedly. Plot-scale fungal diversity was linked to deadwood heterogeneity, and composition of the common species was additionally affected by the living tree structure. Nearly all red-listed species were exclusively found in the near-natural forest plots. These findings demonstrate that clear-cut forestry shifts fungal community structure rather than reducing the total number of species and that rare and common species are structured by different environmental drivers but respond in similar ways to large scale disturbance. C_LIO_LISynthesis: Our results highlight the importance of maintaining structural complexity of deadwood in boreal forests for fungal conservation. We found a consistent relationship between deadwood volumes and heterogeneity, and community diversity and species richness. This relationship was consistent even for previously clear-cut forests, showing that retaining structural heterogeneity in managed ecosystems has a positive impact on species diversity. C_LI

O_LITree cores are widely used across a broad range of disciplines in the environmental sciences, most notably as a tool to measure tree growth, estimate tree age, characterise wood anatomy and reconstruct past climate. However, because extracting tree cores is an invasive procedure, concerns about their use are often raised due to perceived risks for tree health. C_LIO_LIHere we comprehensively test the long-term impacts of tree coring on 16 European tree species using a dataset spanning the entire European continent. Over the course of a decade, we tracked the growth and survival of 3334 trees cored in 2012 (including trees cored once and twice) and compared them to that of a cohort of 7413 neighbouring trees that were never cored. C_LIO_LIWe found no evidence that coring had a detrimental impact on either the growth or survival of trees, irrespective of their size, species, climatic environmental or the number of times they were cored. However, we did observe a small positive stem increment response (2.0% for trees cored once and 6.2% for trees cored twice), which we hypothesise is most likely the result of vertical scarring from the coring wound, with potential consequences for the accuracy of repeated diameter measurements collected at the same height. C_LIO_LIOur study supports the use of tree coring as a low-impact method for characterising the growth, age and function of a wide range of tree species. However, to avoid biasing long-term forest census measurements, tree cores should always be collected well above or below the point of measurement of tree stem diameters. C_LI

Carolinian old-growth forests in southwestern Ontario are among the most biodiverse ecosystems in Canada, yet regeneration of several canopy tree species is increasingly constrained by intense white-tailed deer browsing and changing disturbance regimes. Windstorms frequently uproot trees in this region, creating tip-up mounds that alter soil structure, drainage, and microtopography. These microsites may provide important opportunities for seedling establishment, but their role in forest regeneration remains poorly understood. This study examined how tip-up mound microsites differ from adjacent ground microsites in soil properties and how these differences influence seedling survival. A total of 84 tip-up mounds were sampled across several conservation areas in Hamilton, Ontario. For each mound, soil samples were collected from the mound top and adjacent forest floor and analyzed for soil moisture, pH, organic matter, and texture. Seedlings of two deer-preferred native species, red oak (Quercus rubra) and black cherry (Prunus serotina), were planted on mound tops and adjacent ground microsites, and their survival was monitored over the growing season. Ground microsites had significantly higher soil moisture and organic matter than mound tops, whereas mound tops were consistently drier. Seedling responses differed between species: red oak survival was higher on ground microsites, while black cherry survival was higher on mound tops. Logistic regression analyses indicated that soil moisture was the strongest predictor of seedling survival, with contrasting responses between the two species. These results suggest that tip-up mounds create distinct environmental conditions that selectively favor different regeneration strategies. As white-tailed deer browsing continues to suppress regeneration on the forest floor - particularly in areas of high deer activity and low wildlife species richness - while windthrow frequency rises under climate change, tip-up mounds are poised to become increasingly critical regeneration niches for species capable of establishing under drier, well-aerated microsite conditions.

Biomass and surface area allocation affect resource uptake and carbon (C) residence time in forests, but the influence of tree diversity on allocation remains poorly understood. Moreover, mycorrhizal associations can alter this relationship, which has been rarely tested in mature forests. We investigated the role of both the proportion of ectomycorrhizal (ECM) trees and tree diversity on tree biomass and surface area allocation across a dual gradient of tree diversity (0 - 1.68 Shannon diversity) and ECM dominance (0 - 100 %) in a mixed deciduous forest area in Central Germany. We found that the two gradients affected tree biomass and surface area differently and mostly independently. Tree diversity had no significant effect on biomass or surface area in the investigated forest area, but increased the spatial variability of the leaf area index (LAI) from 21 % to 40 %. In contrast, a higher proportion of ECM trees was associated with an increase in fruit biomass (from 10 to 141 g m-2) and LAI (from 4 to 7 m2 m-2). Although tree diversity and the portion of ECM produced similar parsimonious models for explaining belowground biomass and surface area, neither showed a significant direct effect. Notably, their interaction enhanced the spatial variability of fine root biomass and root surface area; that is, forests with high diversity and a greater proportion of ECM trees exhibited a more heterogeneous distribution of fine roots. Allocation to fine root biomass appeared independent of tree diversity and the proportion of ECM trees, being influenced primarily by stand structure, with higher allocations observed in stands with lower stem basal area. We conclude that biomass allocation in this Central European Forest, where resource availability is relatively uniform, is primarily productivity-driven. A comparison of the biotic influences shows that ECM trees have a stronger control on aboveground surface area and fruit biomass than tree diversity, which may contribute to the ability of dominant ECM trees, such as European beech, to outcompete light competitors, but also puts temperate ECM forests at risk of physiological failures in increasingly drier future conditions.

European mountain forests have been strongly shaped by past human activities, which have influenced their structure and composition. Assessing the natural tree-species composition of current forest landscapes is essential for evaluating their biodiversity potential and for informing management prioritization. High levels of compositional naturalness are often associated with greater ecosystem functioning, but it remains unclear whether forest landscapes that are closer to their potential forest composition are also less vulnerable to future climate change and natural disturbances. Using a process-based forest landscape model, we quantified the naturalness and the vulnerability to disturbances across a large forested area in the Italian Alps. We developed a spatially-explicit index to evaluate how closely current tree species composition matches potential forest composition. We then simulated future forest dynamics under multiple climate change and disturbance scenarios, using two different initial vegetation conditions on the same landscape - potential vs. current forest - and compared their vulnerability based on changes in species dominance, vegetation structure, and height heterogeneity. Results indicate that current forests exhibit generally low naturalness compared with their potential forest composition, reflecting historical management and agro-silvopastoral practices. The naturalness score changed depending on elevation across the landscape: forests at low (<1500 m a.s.l.) and high (>2100 m a.s.l.) elevations had low naturalness, while those in the mid-elevation range (1500-2100 m) exhibited medium to high levels of naturalness. Vulnerability to disturbances under climate change differed markedly between the two initial vegetation conditions. Current forest was more susceptible to bark beetle outbreaks, driven by past promotion of Norway spruce and further amplified by warming. In contrast, the potential forest was more vulnerable to wind disturbance, likely due to old-growth characteristics, such as greater height heterogeneity and canopy roughness, that increase blowdown susceptibility. This study provides the first assessment of forest naturalness using spatially explicit dynamic landscape modelling. Given the projected intensification of natural disturbances under future climates, our findings suggest that promoting more natural forest conditions alone may not guarantee higher resilience to climate-induced disturbances. Instead, management approaches should aim at increasing landscape-level structural and compositional heterogeneity in a balanced manner to minimizing future disturbance vulnerability.

IntroductionPatterns of soil respiration (Rs) are heterogeneous on temporal and spatial scale. The most important controlling factors of soil respiration are microclimatic conditions such as soil temperature and moisture. However, a strong pronounced seasonality shifts Rs patterns from temperature to moisture-controlled regimes. Rarely investigated patterns are time-lagged effects prior to Rs measurements and influences of trees in mixed forests on large spatio-temporal scales. Material and MethodsWe investigated Rs over two years on a weekly to fortnightly measurement rhythm at an approximately 1 ha area in a mixed forest on 35 predefined locations using the common chamber technique. Analysis was derived using meteorological data and a tree species map. ResultsBy tendency, Rs decreased with increasing distance to the tree and we observed significantly higher Rs in broadleaf patches compared to coniferous and mixed patches during the summer season (+27 %, +18 %, respective). Our data confirmed soil temperature and moisture as important controlling variables. Yet, our results highlight an additional predictor explaining a higher proportion in variability: the vapour pressure in the atmosphere. In contrast to soil temperature and moisture this predictor was able to track a collapse in Rs due to drought and increases following rewetting. ConclusionWe conclude that meteorological conditions might be valuable indicators for CO2 emissions from forest soils. Tree species distribution explained partly the spatial patterns and hot spots of Rs yet additional analysis of local soil properties will enhance our understanding of the soil plant interactions and the resulting Rs.

PremiseLong-term phenological patterns are increasingly being examined from the perspective of climate change and its potential effects. Climatic effects on plant phenology could involve the direct responses to changes in temperature, precipitation and solar irradiance, or could be mediated by these variables through exogenous teleconnections such as the El Nino Southern Oscillation (ENSO). The effects of climatic fluctuations on inter-annual variation in tropical phenology remain understudied. MethodsWe examined long-term patterns of tree flowering and fruiting intensity in a tropical forest site in the Eastern Himalayas between 2011 and 2024. Species-specific patterns were examined for 36 species. Long-term patterns were quantified using Generalized Additive Models, and splines were visualized to infer trends. Through Generalized Linear Mixed Models, we determined if there was a lagged phenological response to ENSO and temperature, precipitation and solar irradiance, and whether ENSO effects were being mediated through the latter group of variables or plant traits. ResultsBetween 2011 and 2019, trends in flowering and fruiting were significant for 17 and 23 species respectively. Flowering increased for 7 species, while fruiting declined for 8 species. Flowering peaked during El Nino, but this association did not appear to be mediated through climate variables, whereas fruiting showed a three-month positive lagged response to solar irradiance, independent of ENSO. The peak season of reproduction was the only trait determining species-specific responses to climate variables. ConclusionOur study highlights nonlinearity in long-term patterns of reproductive phenology, and the importance of solar irradiance in determining inter-annual fruit production.

Urban green areas often harbour numerous non-native urban trees, many of which have characteristics that predispose them to escape from cultivation and become potentially invasive. Climate change is expected to exacerbate this risk by creating favourable conditions for species that are currently climatically restricted. The potential risks for invasiveness of urban tree species in continental Europe are not yet known. Here, we provide a comprehensive risk screening of 34 non-native urban tree species in continental Europe, for both current and projected future climate scenarios. Using the Terrestrial Plant Species Invasiveness Screening Kit (TPS-ISK v2.4), we assessed invasion risk based on biogeography, ecology, and projected responses to climate change. Results showed that under current conditions, 10 species (29.4%) were categorised as high risk, 23 (67.6%) as medium risk and one (2.9%) as low risk. The inclusion of climate change projections increased the number of high risk species to 11, with seven species categorised as very high risk. These taxa exhibit strong ecological plasticity, high reproductive performance and broad environmental tolerance, which together with projected warming, emphasises their significant potential for further spread. Our results emphasise the urgent need for early detection, continuous monitoring and proactive management of non-native urban trees in Europe, especially those that are widely used in horticulture and forestry. By integrating invasion biology with climate change risk screening, this study provides an important basis for evidence-based policy and management strategies to mitigate future ecological and economic impacts of invasions by urban trees.

Climate change is increasing the frequency, duration and severity of extreme events such as heatwaves and droughts, pushing trees near or beyond their ecophysiological limits. Understanding what governs variability in how trees respond to drought - such as intrinsic factors related to their size, age, and species, or extrinsic factors shaped by their local competitive environment - is critical for predicting long-term forest resilience to climate change and developing climate-smart forest management strategies. Here, we use tree ring data from 2909 trees belonging to sixteen species distributed across Europes major forest types to comprehensively assess what factors contribute most to a trees ability to withstand and recover from extreme drought events. We found that trees with larger living crowns generally exhibited higher post-drought growth recovery and resilience, while trees exposed to lower drought intensities showed greater resistance. Conversely, neither the density nor the diversity of a trees local competitive neighbourhood had any clear influence on its response to drought. More generally, we found that our ability to predict whether a tree would exhibit resilience to drought was low (R2 = 13-21) and was largely driven by species-specific responses and topographic variation across forest types, rather than by tree- and stand-level attributes. These findings highlight that drought responses are inherently complex and strongly influenced by forest type and by heterogeneous responses among species. Integrating tree-ring, physiological, and remote-sensing data with mechanistic models represents a promising avenue for improving forecasts of future forest resilience to climate change.

Ongoing climate change will negatively impact tree populations unless they are able to acclimate to the changes in their local environment. Effective planning for climate adaptation management requires an understanding of the current state of local adaptation and physiological performance to assess whether populations are at risk of local extinction, to determine if seed movement is appropriate, and to select appropriate seed sources if intervention is needed. We established a new reciprocal transplant experiment (ACE, Adaptation to Climate and Environment) across a latitudinal gradient in North America to examine the impacts of warming on three bur oak (Quercus macrocarpa) populations across much of the species range. We established common gardens in Minnesota, Illinois, and Oklahoma with seedlings grown from seeds collected within 50 km of each of those locations from a total of sixty maternal families. We aimed to 1) assess local adaptation in each of the populations using survival and size as fitness metrics, and 2) evaluate physiological responses to different environments along the latitudinal gradient. We found that northern populations are maladapted to hotter climates as evidenced by their low survival, growth, and photosynthetic rates in the warmest common garden. The southernmost population had the highest survival rate, growth rate, and fitness of the three populations in the southernmost garden, providing evidence for local adaptation to the warmest site. However, conditions in the middle garden resulted in the highest fitness and best physiological performance for all populations. Growth and survival were correlated in the middle garden but were decoupled in the northern and southern gardens. This decoupling is likely due to stress associated with more extreme climates at the ends of the gradient that led to greater resource allocation to survival than to growth. Our results suggest that southern seed sources may perform well in warmer conditions in the north brought on by climate change, which has important implications for managers assisting broadly ranged tree species in adapting to climate change.

Attributes of fire regimes are known to drive habitat suitability for many species in fire-prone environments. Comparatively little is known about how abiotic conditions (e.g. rainfall events, cumulative rainfall, drought) at the time of fire may affect long-term (>2-years) post-fire occurrence. We sought to a) establish whether the post-fire development of heathland habitat for the endangered mallee emu-wren is influenced by rainfall within 12-months before or after the most-recent fire, b) identify the preferred fire-age of heathland vegetation for the mallee emu-wren, and c) map those habitats most likely to support the species across a large reserve ([~]271,000 ha), Ngarkat Conservation Park, from which it has been extirpated. Using historical presence records, collected prior to the extirpation of mallee emu-wrens from the study area, we implemented a random-forest modelling approach to predict relative likelihood of occurrence (considered a proxy for probability of suitable habitat). Rainfall in the 12-months before and after fire had a positive effect on relative likelihood of mallee emu-wren occurrence. The development of high-quality mallee emu-wren habitat required at least 420 mm of rainfall in the 12-months prior to the most recent fire. Only 35% of Ngarkat received rainfall above this threshold prior to the most recent fire. Rainfall in the 12-months after fire positively influenced relative likelihood of mallee emu-wren occurrence, though the effect was less pronounced than pre-fire rainfall. Relative likelihood of mallee emu-wren occurrence peaked 15 years after fire, with an [~]10-year peak time window of relative occurrence (10-20-years). This study highlights that abiotic conditions at the time of fire, particularly rainfall in the 12-months preceding fire, have long-lasting impacts on relative probability of occurrence for this fire-sensitive species. Targeting fire management in ways that maximise post-fire occurrence of the mallee emu-wren - particularly by burning senesced habitat following periods of elevated rainfall - has potential to enhance conservation outcomes. Given the substantial and long-term impact of rainfall around the time of a fire identified in this study, short-term climatic conditions deserve greater attention in a range of ecosystems where managers aim to use fire to manipulate habitat for the benefit of fire-sensitive species.

O_LIMegaherbivores are increasingly promoted as agents of nature restoration, yet most research on their ecological effects has focused on temperate and non-forested systems, with limited consideration of tropical forests and their historical land-use contexts. C_LIO_LIA better understanding of megaherbivore impacts in tropical forests is essential to inform rewilding and restoration efforts. This is particularly important in regenerating secondary systems that historically supported megafaunga and remain highly valuable targets for ecological recovery. C_LIO_LIWe address this knowledge gap by comparing tree species composition, forest structural attributes, and understory habitat composition across three disturbance regimes in an East African tropical dry forest: (1) primary forest with megaherbivores, (2) secondary forest with megaherbivores, and (3) primary forest without megaherbivores. C_LIO_LIUnder megaherbivore presence, understory habitat and tree branching architecture converged across primary and secondary forests, suggesting functional consistency in disturbance effects imposed by large herbivores and indicating that key structural ecosystem processes can be rapidly restored. In contrast, canopy structure and tree species composition remained distinct between forest types and strongly constrained by persistent legacies of past human land use. C_LIO_LIOur findings underscore that restoration strategies relying on megaherbivores must explicitly account for historical land-use constraints rather than assuming spontaneous convergence toward primary-forest conditions. C_LI

Mangroves play a crucial role in supporting global biodiversity and ecosystem functioning, yet how their multidimensional diversity interact and respond under diverse stress conditions remains underexplored. To address this gap, using species, environmental, functional trait and forest structural data collected from the permanent sample plot (PSP) network (110 PSPs) of the worlds largest mangrove ecosystem, the Sundarbans, we answer three key questions: (Q1) How are structural, functional, taxonomic, and phylogenetic diversities interconnected? We hypothesized that these diversity components are positively correlated (H1). (Q2) What are the key environmental stressors and how the diversity components are influenced by multiple stressors? We hypothesized that these stressors negatively affect all diversity components (H2). (Q3) What spatial patterns emerge in the distributions of these diversity components? Here we hypothesized that these diversity components vary across space under changing environmental conditions (H3). Our results show that taxonomic, functional, structural, and phylogenetic diversity have varying degrees of interconnection. While taxonomic and structural diversity are strongly correlated, functional and phylogenetic diversity exhibit more independent patterns, suggesting distinct ecological processes shape each dimension. Salinity, elevation, silt, community structure and downstream-upstream gradient (i.e., upriver position) have strong influences on all the diversity components although the magnitude of the influence varies. GAM results reveal that salinity and siltation act as the primary negative drivers for most dimensions; however, functional richness and divergence show a unique positive response to salinity. Furthermore, we found that community structure and upriver position significantly influence diversity patterns, often in a non-linear fashion. Though taxonomic, structural, and phylogenetic diversity show higher values mainly in the moderate and low saline areas, functional richness shows higher values in high saline areas. Overall, our results provide strong support for all the hypotheses. Our findings highlight the importance of holistic approach integrating taxonomic, structural, functional, and phylogenetic dimensions for maintaining biodiversity and ecosystem functions in dynamic mangrove ecosystems and emphasize the need for conservation efforts that target moderate-stress zones to preserve both ecological and evolutionary diversity. HighlightsO_LIExplored the interconnection between four dimensions of biodiversity (taxonomic, structural, functional, and phylogenetic) and how they respond to multiple stressors in the worlds largest mangrove forest. C_LIO_LIHigh salinity and siltation act as the primary environmental stressors that negatively affect overall biodiversity. C_LIO_LIStructural diversity is strongly related to species richness, serving as a key indicator of ecosystem health. C_LIO_LIFunctional and phylogenetic diversity follow independent spatial patterns, promoting the need for multi-dimensional monitoring. C_LI

Black spruce (Picea mariana [Mill.] B.S.P.) is an emblematic and ubiquitous species of the North Americas boreal forest. While conifer breeding programs have traditionally focused on growth and wood property traits, the study of climate adaptation traits is becoming increasingly prevalent, given the predicted impact of climate change on North Americas boreal zone. Through this study, we aimed to identify genes associated with climate adaptation in black spruce across Canada. A total of 254 black spruce trees from 30 populations, covering most of the species distribution range, were sampled and genotyped for SNPs located in [~]5000 gene loci. Uni- and multivariate Genotype-Environment Association (GEA) approaches, namely LFMM and RDA, as well as an outlier method based on population differentiation (FST) were used to identify genes significantly associated with climatic factors. As such, a total of 77 genes carrying significant candidate SNPs were identified, among which 14 candidates were corroborated by at least two methods. Many of these gene SNPs were also confirmed at a smaller geographic scale, across west - east partitions corresponding to the two main black spruce historical lineages. Notably, significant gene SNPs were more frequently associated to moisture/aridity factors in the western part of the range, and more to temperature factors in the eastern part. The genes carrying these SNPs were also frequently associated to abiotic and biotic stress response. In the context of rapid climate change in the Canadian boreal forest, the results obtained within the framework of this study should support implementing gene conservation efforts while assisting prediction in black spruce breeding programs, which are instrumental to producing adapted planting stock for the large-scale reforestation efforts conducted annually across the Canadian boreal forest.

O_LITropical forest restoration is critical for mitigating biodiversity loss and climate change, including in forests impacted by selective logging. Active restoration through liana cutting and enrichment tree planting can substantially accelerate carbon recovery, potentially reducing economic pressures to convert logged forests. But its long-term biodiversity impacts remain largely unknown. C_LIO_LIUsing over two decades of bird survey data from Borneos largest logged-forest restoration project, we quantified occupancy patterns for 176 species across primary, naturally regenerating, and actively restored logged forests spanning a 30+ year post-logging chronosequence. C_LIO_LIForest-dependent, threatened and near-threatened species generally declined through time in actively restored areas, whereas many species in naturally regenerating forests progressively recovered toward primary forest levels. Between 17-40% of 66 threatened or near-threatened species had consistently lower occupancies in actively restored than in naturally regenerating forest. Across species of global conservation concern, median occupancies in restored areas remained [~]22% below primary forest even 50 years after harvests, compared with only [~]6% lower under natural regeneration. C_LIO_LIArboreal insectivores, frugivores, and predatory species appeared most negatively affected by active restoration, with 27-49% of arboreal gleaning insectivores (of 62), 13-30% of arboreal frugivores (of 40), and one-third of predatory species (of 15) showing higher occupancy in naturally regenerating forests. Sallying insectivores also showed a possible but uncertain response, whereas ground-associated frugivores and insectivores were largely unaffected by restoration treatment. C_LIO_LIConcerningly, even 50 years post-logging, up to 52% of 50 high forest-dependency species retained distinct occupancies in actively restored compared with primary forest, suggesting persistent negative impacts of vine-cutting and/or tree planting activities on avian populations. C_LIO_LISynthesis and applications. Our findings indicate that despite substantial carbon benefits, active restoration within selectively logged forests may impede the recovery of forest-dependent biodiversity. This challenges the common assumption embedded within nature-based climate solutions that carbon and biodiversity outcomes will necessarily align. Nonetheless, despite the persistent declines in bird communities, actively restored forests continued to provide key habitat for many species. Active interventions may thus still contribute to broader biodiversity conservation objectives if they protect logged areas from conversion, potentially via carbon payments. C_LI

This study evaluated the effectiveness of genomic selection (GS) in loblolly pine (Pinus taeda) using a two-generation closed breeding population and a genetically diverse Mainline population. Single-step genomic best linear unbiased prediction (ssGBLUP) models were used to include all phenotypic, genotypic, and pedigree information. Prediction accuracies of genomic estimated breeding values reached up to 0.70 for stem volume and stem straightness. Prediction accuracy showed a strong linear relationship with mean relatedness between training and validation populations (r > 0.92). Adjusting the scaling between genomic and pedigree relationship matrices improved model stability, increased prediction accuracy, and reduced bias in genomic estimated breeding values. Estimates of heritability and variance components from ssGBLUP were consistent with pedigree-based models, particularly when genomic relationships were properly scaled. Genomic selection had approximately 50% more genetic gain per year relative to conventional selection. Overall, these results demonstrate that GS can be effectively integrated into operational conifer breeding programs, given sustained investment in large, well-connected training populations with high-quality phenotypic data. We also outline the planned implementation of GS in the North Carolina State University Cooperative Tree Improvement Program to increase genetic gain.

By concentrating rodents along verges, roads can reshape rodent-mediated seed dispersal, yet empirical tests remain scarce. We conducted a two-year field experiment in Mediterranean oak woodlands in southern Portugal to test how seed dispersal varies with distance from roads across road type (paved vs. unpaved) and road-forest context (edge vs. non-edge). We tracked labeled holm oak acorns, recording dispersal distances and the number of dispersal events. The two metrics responded differently to road distance. Dispersal distances changed little with distance from roads in non-edge contexts but increased in edge road-forest contexts (2x longer at 400 m than at 10 m) and showed a year x distance-to-road interaction, with longer dispersal distances farther from roads in the second year (a poor mast year). Dispersal distances were also longer when acorns were deposited under shrubs and in areas of higher tree density, and decreased with greater natural acorn availability. In contrast, the number of dispersal events declined with distance from roads (30% more events at 10 m than at 400 m) and was higher along unpaved than paved roads (39% more events). Dispersal frequency also increased in the poor mast year and with shrub cover. No acorns crossed the road. Thus, road verges can concentrate rodent seed handling but do not increase dispersal distances near roads nor provide cross-road seed connectivity; instead, dispersal outcomes depend on edge context, road type, and microhabitat structure. Management that retains structural cover at verges and the adjacent forest edge (e.g., shrub patches and non-uniform clearing) can harness verge-associated activity to increase acorn deposition in sheltered microsites and promote regeneration farther into forest interiors in roaded landscapes.