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Summary: Current estimates of temperature effects on plants mostly rely on air temperature, although it can significantly deviate from leaf temperature (Tleaf). To address this, some studies have used canopy temperature (Tcan). However, Tcan fails to capture the fine‐scale variation in Tleaf among leaves and species in diverse canopies.We used infrared radiometers to study Tleaf and Tcan and how they deviate from air temperature (ΔTleaf and ΔTcan) in multispecies tropical tree plantations at three sites along an elevation and temperature gradient in Rwanda.Our results showed high Tleaf (up to c. 50°C) and ΔTleaf (on average 8–10°C and up to c. 20°C) of sun‐exposed leaves during 10:00 h–15:00 h, being close to or exceeding photosynthetic heat tolerance thresholds. These values greatly exceeded simultaneously measured values of Tcan and ΔTcan, respectively, leading to strongly overestimated leaf thermal safety margins if basing those on Tcan data. Stomatal conductance and leaf size affected Tleaf and Tcan in line with their expected influences on leaf energy balance.Our findings highlight the importance of leaf traits for leaf thermoregulation and show that monitoring Tcan is not enough to capture the peak temperatures and heat stress experienced by individual leaves of different species in tropical forest canopies. [ABSTRACT FROM AUTHOR]

Aim: To test the hypothesis that adaptive shifts leading to the assembly of tropical savannas involved coordination between bark and wood traits and to understand the underlying mechanisms. Location: Tropical South America. Taxon: Angiosperms (woody). Methods: We compiled data on three bark traits (total, inner and outer relative bark thickness), wood density, maximum height, five secondary xylem traits and on species' habitat information (light environment, climate, soil and fire history) for Neotropical savanna, forest and generalist species (biome groups). We tested for pairwise and multivariate associations among traits across species and if biome group and habitat conditions explained species positions along the resulting strategy axes. Results: Traits covaried along four different axes. The first axis was consistent with a trade‐off between fire (thick barks) and shade tolerance (low bark to diameter ratio, high vessel density) and contributed to differentiate the three biome groups according to the preference for shaded environments. Forest species also differed from savanna and generalist species in a separate axis by being more resource acquisitive. Maximum height and wood density did not strongly trade‐off with bark thickness, although maximum height was negatively covaried with relative outer bark thickness. Preference for shaded conditions was the main driver of variation in the two principal strategy axes, but temperature, fire and soil sand content also explained differences in plant stature between savanna and generalist species. Main Conclusions: Allocation to bark is constrained by trade‐offs with wood, opposing shade‐tolerant and acquisitive forest species to fire‐resistant and conservative savanna species. Rather than a single strategy axis, three axes are necessary to understand the functional differences among savanna, forest and generalist species. Because two of these axes are controlled by light availability, the associated traits tend to covary in space and time, but not across species. [ABSTRACT FROM AUTHOR]

The Amazon forest contains globally important carbon stocks, but in recent years, atmospheric measurements suggest that it has been releasing more carbon than it has absorbed because of deforestation and forest degradation. Accurately attributing the sources of carbon loss to forest degradation and natural disturbances remains a challenge because of the difficulty of classifying disturbances and simultaneously estimating carbon changes. We used a unique, randomized, repeated, very high-resolution airborne laser scanning survey to provide a direct, detailed, and high-resolution partitioning of aboveground carbon gains and losses in the Brazilian Arc of Deforestation. Our analysis revealed that disturbances directly attributed to human activity impacted 4.2% of the survey area while windthrows and other disturbances affected 2.7% and 14.7%, respectively. Extrapolating the lidar-based statistics to the study area (544,300 km²), we found that 24.1, 24.2, and 14.5 Tg C y-1 were lost through clearing, fires, and logging, respectively. The losses due to large windthrows (21.5 Tg C y-1) and other disturbances (50.3 Tg C y-1) were partially counterbalanced by forest growth (44.1 Tg C y-1). Our high-resolution estimates demonstrated a greater loss of carbon through forest degradation than through deforestation and a net loss of carbon of 90.5 ± 16.6 Tg C y-1 for the study region attributable to both anthropogenic and natural processes. This study highlights the role of forest degradation in the carbon balance for this critical region in the Earth system. [ABSTRACT FROM AUTHOR]

A fundamental challenge for ecologists is to evaluate the effects of anthropogenic disturbance on ecosystem processes and functions. Tropical rainforests in Borneo are biologically diverse and provide an array of ecosystem functions and services. However, these forests are being logged and converted to agricultural plantations at a rapid pace. While there are numerous studies on the impacts of these land-use changes on biodiversity, there are far fewer that investigate the consequences of forest disturbance for ecosystem functioning. We investigated the impacts of land-use change in Bornean tropical rainforests on invertebrate-mediated functions using a suite of six easily measurable processes that are linked to nutrient cycling and plant regeneration, and which can be used as indicators of the degree of disturbance and the health of the forest. We explored whether the conversion of primary forest to logged, fragmented forest or agricultural plantations altered the ecosystem processes of dung removal, predation of insect herbivores, functional activity of soil invertebrates, bioturbation, seed removal, and decomposition. Overall, ecosystem processes remained resistant to habitat change except for seed removal, which was lower in heavily logged forests and plantations than in primary forests. This suggests that, despite the loss of many species when forests are logged and converted to agriculture, ecosystem processes provided by invertebrates can remain robust across land-use gradients. [ABSTRACT FROM AUTHOR]

Simple Summary: Invasive species are considered a threat to the conservation of different environments. Annotating the numbers and species of these invasive organisms is critical to developing conservation strategies. This research gives background information on the types and possible origins of invasive species from the arthropod and chordate groups in Panama. The results indicated that approximately 141 exotic arthropod and chordate species have been reported as invasive species in Panama. Most of these species are believed to have been introduced via the Panama Canal Zone or accidentally. With the information compiled, this study will serve as preliminary data on the sources of introduction and will provide information for future research and plans to prevent the impact of those species. Invasive species are one of the five main causes of biodiversity loss, along with habitat destruction, overexploitation, pollution, and climate change. Numbers and species of invasive organisms represent one of the first barriers to overcome in ecological conservation programs since they are difficult to control and eradicate. Due to the lack of records of invasive exotic species in Panama, this study was necessary for identifying and registering the documented groups of invasive species of the Chordates and Arthropod groups in Panama. This exhaustive search for invasive species was carried out in different bibliographic databases, electronic portals, and scientific journals which addressed the topic at a global level. The results show that approximately 141 invasive exotic species of the Arthropoda and Chordata phyla have been reported in Panama. Of the 141 species, 50 species belonged to the Arthropoda phylum and 91 species belonged to the Chordate phylum. Panamanian economic activity could facilitate the introduction of alien species into the country. This study provides the first list of invasive exotic chordate and arthropod species reported for the Republic of Panama. [ABSTRACT FROM AUTHOR]

Aim: Successional changes in functional diversity provide insights into community assembly by indicating how species are filtered into local communities based on their traits. Here, we assess successional changes in taxonomic and functional richness, evenness and redundancy along gradients of climate, soil pH and forest cover. Location: Neotropics. Time period: Last 0–100 years. Major taxa studied: Trees. Methods: We used 22 forest chronosequence studies and 676 plots across the Neotropics to analyse successional changes in Hill's taxonomic and functional diversity of trees, and how these successional changes vary with continental‐scale gradients in precipitation, soil pH and surrounding forest cover. Results: Taxonomic and functional richness and functional redundancy increased, while taxonomic and functional evenness decreased over time. Functional richness and evenness changed strongly when not accounting for taxonomic richness, but changed more weakly after statistically accounting for taxonomic richness, indicating that changes in functional diversity are largely driven by taxonomic richness. Nevertheless, the successional increases in functional richness when correcting for taxonomic richness may indicate that environmental heterogeneity and limiting similarity increase during succession. The taxonomically‐independent successional decreases in functional evenness may indicate that stronger filtering and competition select for dominant species with similar trait values, while many rare species and traits are added to the community. Such filtering and competition may also lead to increased functional redundancy. The changes in taxonomically‐independent functional diversity varied with resource availability and were stronger in harsh, resource‐poor environments, but weak in benign, productive environments. Hence, in resource‐poor environments, environmental filtering and facilitation are important, whereas in productive environments, weaker abiotic filtering allows for high initial functional diversity and weak successional changes. Main conclusion: We found that taxonomic and functional richness and functional redundancy increased and taxonomic and functional evenness decreased during succession, mainly caused by the increasing number of rare species and traits due to the arrival of new species and due to changing (a)biotic filters. [ABSTRACT FROM AUTHOR]

Our aim was to evaluate whether the richness and composition of anurans responded to the time of forest regeneration via secondary succession. We sampled the anuran community in a mosaic of areas at three different stages of secondary succession in the Atlantic Forest, southern Brazil. The anurans were collected from nine lentic ponds and from their margins up to a 50 m radius. The late secondary forest sheltered the higher species richness, followed by the primary forest. The spatial variation in species richness was related to the forest succession stage and predominance of arboreal vegetation on the pond edge. The species composition changed throughout the succession stages, regardless of the distance among areas. Along the gradient of forest succession, environmental changes have driven species distribution, limiting the occurrence of forest species and favoring the colonization of areas at the early succession stage by opportunist species. We could observe that the secondary forest succession was a determining factor in the anuran community structure, and with the advancement of the secondary succession, both richness and composition were partly restored. Thus, the conservation of secondary forests might be an efficient strategy to preserve the biodiversity in areas of the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Summary: Elevated air temperature (Tair) and vapour pressure deficit (VPDair) significantly influence plant functioning, yet their relative impacts are difficult to disentangle.We examined the effects of elevated Tair (+6°C) and VPDair (+0.7 kPa) on the growth and physiology of six tropical tree species. Saplings were grown under well‐watered conditions in climate‐controlled glasshouses for 6 months under three treatments: (1) low Tair and low VPDair, (2) high Tair and low VPDair, and (3) high Tair and high VPDair. To assess acclimation, physiological parameters were measured at a set temperature.Warm‐grown plants grown under elevated VPDair had significantly reduced stomatal conductance and increased instantaneous water use efficiency compared to plants grown under low VPDair. Photosynthetic biochemistry and thermal tolerance (Tcrit) were unaffected by VPDair, but elevated Tair caused Jmax25 to decrease and Tcrit to increase. Sapling biomass accumulation for all species responded positively to an increase in Tair, but elevated VPDair limited growth.This study shows that stomatal limitation caused by even moderate increases in VPDair can decrease productivity and growth rates in tropical species independently from Tair and has important implications for modelling the impacts of climate change on tropical forests. [ABSTRACT FROM AUTHOR]

Aim: The efficiency of animal‐mediated seed dispersal is threatened by the decline of animal populations, especially in tropical forests. We hypothesise that large‐seeded plants with animal‐mediated dispersal tend to have limited geographic ranges and face an increased risk of extinction due to the potential decline in seed dispersal by large‐bodied fruit‐eating and seed‐dispersing animals (frugivores). Location: Atlantic Forest, Brazil, South America. Taxon: Angiosperms. Methods: First, we collected dispersal‐related traits (dispersal syndrome, fruit size, and seed size), growth form (tree, climber, and other) and preferred vegetation type (open and closed) data for 1052 Atlantic Forest plant species. Next, we integrated these with occurrence records, extinction risk assessments, and phylogenetic trees. Finally, we performed phylogenetic generalised least squares regressions to test the direct and interactive effects of dispersal‐related traits and vegetation type on geographical range size. Results: Large‐seeded species had smaller range sizes than small‐seeded species, but only for species with animal‐mediated dispersal, not for those dispersed by abiotic mechanisms. However, plants with abiotic dispersal had overall smaller range sizes than plants with animal‐mediated dispersal. Furthermore, we found that species restricted to forests had smaller ranges than those occurring in open or mixed vegetation. Finally, at least 29% of the Atlantic Forest flora is threatened by extinction, but this was not related to plant dispersal syndromes. Main Conclusions: Large‐seeded plants with animal‐mediated dispersal may be suffering from dispersal limitation, potentially due to past and ongoing defaunation of large‐bodied frugivores, leading to small range sizes. Other factors, such as deforestation and fragmentation, will probably modulate the effects of dispersal on range size, and ultimately extinction. Our study sheds light on the relationship between plant traits, mutualistic interactions, and distribution that are key to the functioning of tropical forests. [ABSTRACT FROM AUTHOR]

Summary: Stem respiration constitutes a substantial proportion of autotrophic respiration in forested ecosystems, but its drivers across different spatial scales and land‐use gradients remain poorly understood. This study quantifies and examines the impact of logging disturbance on stem CO2 efflux (EA) in Malaysian Borneo.EA was quantified at tree‐ and stand‐level in nine 1‐ha plots over a logging gradient from heavily logged to old‐growth using the static chamber method.Tree‐level results showed higher EA per unit stem area in logged vs old‐growth plots (37.0 ± 1.1 vs 26.92 ± 1.14 g C m−2 month−1). However, at stand‐level, there was no difference in EA between logged and old‐growth plots (6.7 ± 1.1 vs 6.0 ± 0.7 Mg C ha−1 yr−1) due to greater stem surface area in old‐growth plots. Allocation to growth respiration and carbon use efficiency was significantly higher in logged plots. Variation in EA at both tree‐ and stand‐level was driven by tree size, growth and differences in investment strategies between the forest types.These results reflect different resource allocation strategies and priorities, with a priority for growth in response to increased light availability in logged plots, while old‐growth plots prioritise maintenance and cell structure. [ABSTRACT FROM AUTHOR]

Plant species diversity is key to ecosystem functioning, but in recent decades anthropogenic activities have prompted an alarming decline in this community trait. Thus, developing strategies to understand diversity dynamics based on affordable and efficient remote sensing monitoring is essential, as well as examining the relevance of spatial scale and vegetation structural complexity to these dynamics. Here, we used two mathematical approaches to assess the relationship between tropical woody species diversity and spectral diversity in a human-modified landscape in two vegetation types differing in their degree of complexity. Vegetation complexity was measured through the fraction of species that concentrate different proportions of the cumulative importance value index. Species diversity was assessed using Hill numbers at three spatial scales, and metrics of spectral heterogeneity, vegetation indices, as well as raw data from Landsat 9 and Sentinel-2 sensors were calculated and analysed through general linear models (GLM) and Random Forest. Vegetation complexity emerged as an important variable in modelling species from remote sensing metrics, indicating the need to model species diversity by vegetation type rather than region. Hill numbers showed different relationships with remotely sensed metrics, in consistency with the scale-dependency of ecological processes on species diversity. Contrary to multiple previous reports, in our study, GLMs produced the best fits between Hill numbers of all orders and remotely sensed metrics. If we are to meet the need of conducting efficient and speedy woody species diversity monitoring globally, we propose modelling this diversity from remotely-sensed variables as an attractive strategy, so long as the intrinsic properties of each vegetation type are acknowledged to avoid under- or overestimation biases. [ABSTRACT FROM AUTHOR]

Forest above-ground biomass (AGB) is one of the critical measures of forest resources. Therefore, it is crucial to identify a reliable method to estimate the AGB, especially in the tropics, where forest ecosystems are exposed to several depleting factors, including deforestation, climate change and replacing natural forests with palm oil tree plantations. We investigated the digital elevation data over the forest and uses an artificial intelligence-based approach to develop a method for quick and cost-effective assessment of the AGB. The study was conducted in the tropical peatland rainforest of Brunei Darussalam. The Shuttle Radar Topography Mission (SRTM) elevation data product and Light Detection and Ranging (LiDAR) digital elevation data were used. A linear regression (LR) model and three different machine learning (ML) algorithms, i.e., Random Forest (RF), Artificial Neural Network (ANN) and Support Vector Machines (SVM), were tested and compared. As model inputs, the SRTM elevation and distance from the peat dome’s center, a feature of a peatland swamp forest, were used. ML methods were trained on the samples taken from the LiDAR elevations. The validation results showed that the SVM was the best method to predict AGB in the study area with R² = 0.70, RMSE = 83.65 Mg ha-1, and MAE = 74.43 Mg ha-1, which in relative terms corresponds to approximately 6% of the AGB of the forest of interests. This study demonstrated the potential of ML algorithms in AGB estimation based on canopy height derived from the InSARbased DEM in tropical forests. [ABSTRACT FROM AUTHOR]

Dynamic ecosystems, such as the Amazon forest, are expected to show critical slowing down behavior, or slower recovery from recurrent small perturbations, as they approach an ecological threshold to a different ecosystem state. Drought occurrences are becoming more prevalent across the Amazon, with known negative effects on forest health and functioning, but their actual role in the critical slowing down patterns still remains elusive. In this study, we evaluate the effect of trends in extreme drought occurrences on temporal autocorrelation (TAC) patterns of satellite-derived indices of vegetation activity, an indicator of slowing down, between 2001 and 2019. Differentiating between extreme drought frequency, intensity, and duration, we investigate their respective effects on the slowing down response. Our results indicate that the intensity of extreme droughts is a more important driver of slowing down than their duration, although their impacts vary across the different Amazon regions. In addition, areas with more variable precipitation are already less ecologically stable and need fewer droughts to induce slowing down. We present findings indicating that most of the Amazon region does not show an increasing trend in TAC. However, the predicted increase in extreme drought intensity and frequency could potentially transition significant portions of this ecosystem into a state with altered functionality. [ABSTRACT FROM AUTHOR]

Fires were historically rare in tropical forests of West and Central Africa, where dense vegetation, rapid decomposition, and high moisture limit available fuels. However, increasing heat and drought combined with forest degradation and fragmentation are making these areas more susceptible to wildfires. We evaluated historical patterns of Moderate Resolution Imaging Spectroradiometer active fires in African tropical forests from 2003 to 2021. Trends were mostly positive, particularly in the northeastern and southern Congo Basin, and were concentrated in areas with high deforestation. Year‐to‐year variation of fires was synchronized with increasing temperature and vapor pressure deficit. There was anomalously high fire activity across the region during the 2015–2016 El Niño. These results contrast with the drier African woodlands and savannas, where fire has been decreasing. Further attention to fires in African tropical forests is needed to understand their global impacts on carbon dynamics and their local implications for biodiversity and human livelihoods. Plain Language Summary: Fires have historically been rare in the moist tropical forests of West and Central Africa. However, these forests are becoming more vulnerable to fire because climate change is causing higher temperatures and drought stress in the tropics. Human activities such as agriculture, logging, and mining also fragment the remaining forests and make them more susceptible to fire. We used measurements of actively burning fires from Earth observing satellites to study how the amount of fire in African tropical forests has changed from 2003 to 2021. There were several areas with strong trends of increasing fire, mainly in the Congo Basin. In contrast, there were almost no locations where fire was decreasing. The increasing fire trends occurred in locations where deforestation was occurring and climate was becoming warmer and drier. During 2015–2016 global weather patterns caused by an exceptionally strong El Niño event were associated with higher‐than‐normal fire activity throughout the tropical forests in West and Central Africa. Increasing fire is a concern because it can release greenhouse gasses into the atmosphere, reduce the amount of carbon stored in the African tropics, degrade habitats for species that live in tropical forests, and decrease the amounts of wood, food, medicine and other resources that forests provide for humans. Key Points: Active fire detections increased from 2003 to 2021 across Central Africa, with positive fire trends concentrated in the Congo BasinFire increased in areas with high deforestation and the trends were synchronized with increasing temperature and vapor pressure deficitThere was higher‐than‐usual fire activity in tropical African forests associated with the exceptionally strong 2015–2016 El Niño event [ABSTRACT FROM AUTHOR]

Summary As temperature rises, net carbon uptake in tropical forests decreases, but the underlying mechanisms are not well understood. High temperatures can limit photosynthesis directly, for example by reducing biochemical capacity, or indirectly through rising vapor pressure deficit (VPD) causing stomatal closure. To explore the independent effects of temperature and VPD on photosynthesis we analyzed photosynthesis data from the upper canopies of two tropical forests in Panama with Generalized Additive Models. Stomatal conductance and photosynthesis consistently decreased with increasing VPD, and statistically accounting for VPD increased the optimum temperature of photosynthesis (Topt) of trees from a VPD‐confounded apparent Topt of c. 30–31°C to a VPD‐independent Topt of c. 33–36°C, while for lianas no VPD‐independent Topt was reached within the measured temperature range. Trees and lianas exhibited similar temperature and VPD responses in both forests, despite 1500 mm difference in mean annual rainfall. Over ecologically relevant temperature ranges, photosynthesis in tropical forests is largely limited by indirect effects of warming, through changes in VPD, not by direct warming effects of photosynthetic biochemistry. Failing to account for VPD when determining Topt misattributes the underlying causal mechanism and thereby hinders the advancement of mechanistic understanding of global warming effects on tropical forest carbon dynamics. [ABSTRACT FROM AUTHOR]

Ecologists have historically sought to identify the mechanisms underlying the maintenance of local species diversity. High-dimensional trait-based relationships, such as alternative phenotypes, have been hypothesized as important for maintaining species diversity such that phenotypically dissimilar individuals compete less for resources but have similar performance in a given environment. The presence of alternative phenotypes has primarily been investigated at the community level, despite the importance of intraspecific variation to diversity maintenance. The aims of this research are to (1) determine the presence or absence of intraspecific alternative phenotypes in three species of tropical tree seedlings, (2) investigate if these different species use the same alternative phenotypes for growth success, and (3) evaluate how findings align with species co-occurrence patterns. We model species-specific relative growth rate with individual-level measurements of leaf mass per area (LMA) and root mass fraction (RMF), environmental data, and their interactions. We find that two of the three species have intraspecific alternative phenotypes, with individuals within species having different functional forms leading to similar growth. Interestingly, individuals within these species use the same trait combinations, high LMA × low RMF and low LMA × high RMF, in high soil nutrient environments to acquire resources for higher growth. This similarity among species in intraspecific alternative phenotypes and variables that contribute most to growth may lead to their negative spatial co-occurrence. Overall, we find that multiple traits or interactions between traits and the environment drive species-specific strategies for growth, but that individuals within species leverage this multi-dimensionality in different ways for growth success. [ABSTRACT FROM AUTHOR]

Understanding how tropical forests respond to abiotic environmental changes is critical for preserving biodiversity, mitigating climate change, and maintaining ecosystem services in the coming century. To evaluate the relative roles of the abiotic environment and human disturbance on Central African tree community composition, we employ tree inventory data, remotely sensed climatic data, and soil nutrient data collected from 30 1‐ha plots distributed across a large‐scale observational experiment in forests that had been differently impacted by logging and hunting in northern Republic of Congo. We show that the composition of Afrotropical plant communities at this scale responds to human disturbance more than to climate, with particular sensitivities to hunting and distance to the nearest village (a proxy for other human activities, including tree‐cutting and gathering). These findings contrast neotropical predictions, highlighting the unique ecological, evolutionary, and anthropogenic history of Afrotropical forests. [ABSTRACT FROM AUTHOR]

Knowledge about the vertical structure of forests, such as forest height, above-ground biomass (AGB), and the vertical biomass distribution is important for understanding carbon allocation, structural diversity, and succession and degradation dynamics in forest ecosystems. While the use of lidar (light detection and ranging) observations is well established to investigate the vertical structure of forests, the sensitivity of P-band synthetic aperture radar tomography (TomoSAR) observations to biomass and vertical forest structure is not yet well understood. Here we use lidar observations from NASA's Global Ecosystem Dynamics Investigation (GEDI) to analyse the sensitivity of airborne P-band SAR tomography backscatter to forest height and AGB at two tropical forests in Lopé and Mondah, Gabon, Africa. We use GEDI observations to parametrize an empirical model for estimating forest height and we use a random forest model for estimating AGB from TomoSAR profiles. The validation with Land, Vegetation, and Ice Sensor (LVIS) airborne lidar data shows moderate performance for estimating forest height (RMSE = 8.2 m in Lopé and 9.8 m in Mondah) and moderate to good performance for total AGB (RMSE = 115.3 Mg/ha in Lopé and 117.8 Mg/ha in Mondah). We also estimated the vertical distribution of AGB using the corrected TomoSAR backscatter and compared it with AGB profiles derived from field observations in Mondah, which indicates potential to use TomoSAR observations for estimating vertical AGB distribution over tropical forests. However, our results demonstrate the need for targeted field observations of vertical biomass profiles in order to make full use of P-band TomoSAR to map the vertical structure of tropical forests. [ABSTRACT FROM AUTHOR]

The response of plants to increasing atmospheric CO2 depends on the ecological context where the plants are found. Several experiments with elevated CO2 (eCO2) have been done worldwide, but the Amazonian forest understory has been neglected. As the central Amazon is limited by light and phosphorus, understanding how understory responds to eCO2 is important for foreseeing how the forest will function in the future. In the understory of a natural forest in the Central Amazon, we installed four open‐top chambers as control replicates and another four under eCO2 (+250 ppm above ambient levels). Under eCO2, we observed increases in carbon assimilation rate (67%), maximum electron transport rate (19%), quantum yield (56%), and water use efficiency (78%). We also detected an increase in leaf area (51%) and stem diameter increment (65%). Central Amazon understory responded positively to eCO2 by increasing their ability to capture and use light and the extra primary productivity was allocated to supporting more leaf and conducting tissues. The increment in leaf area while maintaining transpiration rates suggests that the understory will increase its contribution to evapotranspiration. Therefore, this forest might be less resistant in the future to extreme drought, as no reduction in transpiration rates were detected. Summary statement: The Amazonian understory plants demonstrate a remarkable response to elevated CO2, including an increase in leaf area and a higher investment in the maximum electron transport rate. These findings suggest enhanced carbon storage and water flux, stressing the important role of the understory in the overall functioning of the forest ecosystem. [ABSTRACT FROM AUTHOR]

Background and aims: There is still limited knowledge regarding the dynamics of soil microbial community structures and functional groups during forest secondary succession after rubber monocultures (RP) abandonment. Methods: Bacterial and fungal communities and functions were investigated for the soil from six forest stands with three replicate plots. Selected stands included an RP, four spontaneous secondary forest stands that formed after RP abandonment at 1 (SF_1), 10 (SF_10), 20 (SF_20), and 40 (SF_40) years, as well as a primary forest (PF, approximately 100 years). Results: After RP abandonment, the alpha-diversity metrics of soil microbial communities increased during the first 40 years of succession but decreased in PF. The biomarkers Proteobacteria and Mortierellomycota increased significantly (P < 0.05) by 84% and 633% in PF, respectively, while Firmicutes showed a significant decrease of 89% in comparison with SF_1. Secondary succession increased the relative abundance of bacterial functional groups related to carbon cycling and fungal functional groups (especially ericoid mycorrhizal). Soil pH was the main edaphic factor in shaping microbial communities and functions. In addition, soil moisture and seasonal variations had direct impacts on fungal communities and bacterial functions. Conclusions: Collectively, these findings suggest that different successional trajectories occur in bacteria and fungi, owing to their divergent responses to the changes in season, soil moisture, and nutrients. Specifically, the frequent shifts in bacterial dominant phyla during succession, as well as the increased susceptibility of diversity and functional groups to season, indicate that bacteria respond more quickly to disturbances compared to fungi. [ABSTRACT FROM AUTHOR]

Research Highlight: Birch, B. D. J., Mills, S. C., Socolar, J. B., Martínez‐Revelo, D. E., Haugaasen, T., & Edwards, D. P. (2024). Land sparing outperforms land sharing for Amazonian bird communities regardless of surrounding landscape context. Journal of Applied Ecology, https://doi.org/10.1111/1365‐2664.14596. Tropical forests are globally threatened by agricultural activities, including cattle farming. The land sharing versus land sparing debate has often been used as a means of addressing the trade‐off between agricultural production and biodiversity conservation, without finding a consensus within the scientific community. Moving forward, recent studies suggest combining both land allocation strategies, where wildlife‐friendly habitats within farmlands could allow movements of species within the agricultural matrix and connect natural habitats such as forest blocks, though this has rarely been demonstrated with empirical studies. In their study, Birch et al. tested how wildlife‐friendly habitats within and around cattle pastures could rescue the negative effects of converting forest to farmland on Amazon bird communities. To do so, they modelled bird species occupancies and simulated different land sharing versus land sparing scenarios with varying amount of landscape‐scale wildlife‐friendly habitat and levels of production. They found that the land sparing strategy outperformed land sharing in all scenarios, with limited benefits of landscape‐scale wildlife‐friendly habitat. This result was mostly driven by forest‐dependent species that cannot persist in farmlands. As these species are highly sensitive, preserving large blocks of primary forest is critical for their conservation. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) are central to sustainability targets, yet few evaluations explore outcomes for both conservation and development, or the trade‐offs involved. We applied counterfactual analyses to assess the extent to which PAs maintained forest cover and influenced well‐being across >31,000 villages in Sumatra and Kalimantan, Indonesia. We examined multidimensional aspects of well‐being, tracking education, health, living standards, infrastructure, environment, and social cohesion in treatment and control villages between 2005 and 2018. Overall, PAs were effective at maintaining forest cover compared to matched controls and were not detrimental to well‐being. However, impacts were highly heterogeneous, varying by island and strictness of protection. While health, living standards, and infrastructure aspects of well‐being improved, education access, environmental conditions, and social cohesion declined. Our analysis reveals the contexts through which individual PAs succeed or fail in delivering multiple benefits and provides insights into where further on‐ground support is needed to achieve conservation and development objectives. [ABSTRACT FROM AUTHOR]

El Niño/Southern Oscillation (ENSO) is the main climate mode that drives the interannual variability in climate and consequently vegetation greenness. While widespread green‐up has been reported and examined in tropical America during El Niño, it remains unclear how vegetation in tropical Asia changes during the period. Here, we used four remote sensing‐based leaf area index (LAI) products to investigate changes in vegetation greenness during the 2015/16 El Niño in tropical Asia. We found a strong green‐up during the 2015/16 El Niño in tropical Asia, with its regional average LAI stronger than that of tropical America. The drivers for the green‐up vary across the region, with radiation being the main driver for continental tropical Asia, and temperature and soil water anomalies in the west and east parts of maritime tropical Asia, respectively. These findings provide important insights into the response of tropical Asia's vegetation to extreme climate anomalies. Plain Language Summary: El Niño is a climate pattern that is associated with warm and dry conditions in tropical forest regions. Significant climatic changes during El Niño thus affect vegetation greenness (i.e., growth, size of canopy, amount of leaves). While an increase in vegetation greenness has been reported in tropical America during El Niño, it remains unclear how vegetation in tropical Asia changes during the period. Here, we used satellite data to investigate changes in vegetation greenness during El Niño in 2015–2016 in tropical Asia. We found a strong increase in vegetation greenness in tropical Asia during this period. The cause of this increase in greenness varied across different parts of tropical Asia. In mainland tropical Asia, sunlight was the main driver, while in maritime Southeast Asia, temperature or soil moisture was the main driver. These findings help provide better understanding of how vegetation in tropical Asia responds to extreme climate events like El Niño. Key Points: Tropical Asia experienced strong green‐up during the 2015/16 El Niño, stronger than that of tropical AmericaIn continental tropical Asia, green‐up was mostly driven by anomalously high shortwave radiationIn maritime tropical Asia, green‐up was primarily driven either by anomalously warmer temperatures or drier soil moisture from the west to east [ABSTRACT FROM AUTHOR]

Given the severe anthropogenic pressure on tropical forests and the high demand for field observations of ecosystem characteristics, it is crucial to collect such data both in pristine tropical forests and in the converted deforested land cover classes. To gain insight into the ecosystem characteristics of pristine tropical forests, regrowth forests, and cashew plantations, we established an ecosystem monitoring site in Phnom Kulen National Park, Cambodia. Here, we present observed datasets of forest inventories, leaf area index, leaf traits of woody species, a fraction of intercepted photosynthetically active radiation, and edaphic and meteorological conditions. We examined how land-use and land-cover change affect species and functional diversity, stand structure, and edaphic conditions among the three land-cover classes. We further investigated relationships between diameters at breast height and tree height, estimated aboveground biomass (AGB), and explored relationships between ecosystem characteristics and AGB. We uncovered some key differences in ecosystem characteristics among the land-cover classes. We also demonstrated the feasibility of locally updating AGB estimates using power law functions. These datasets and findings can contribute to filling data gaps in tropical forest research, addressing global environmental challenges, and supporting sustainable forest management. [ABSTRACT FROM AUTHOR]

The study aimed to identify Conservation Priority Sites (CPS) in the southern Sinaloa region, Mexico, using the Determination Index (DET) method. This method utilizes criteria such as Specific Diversity Index, Ratio of Species of Concern, Relative Scarcity Index, and Habitat Fragility Index to assess conservation stakes over wild plant species and habitats. In 2017 eight sampling sites were evaluated, two in mangroves, three in dry forests and three in semi-deciduous forests, each plot/area covers 0.12 hectares. Speciesarea curves were analyzed to quantify species diversity. A Floristic Originality Index determined the ratio of species of concern. A relative scarcity index was calculated from each type of vegetation surface area. Fragility of habitats was estimated over five levels of resilience. The results identified semi-deciduous forest sites as the highest conservation priorities due to their higher species diversity, number of species of concern, and scarce surface area. The DET method facilitated the ranking of CPS in the study area and is recommended as a valuable tool for landscape planning and conservation efforts. [ABSTRACT FROM AUTHOR]

A new Mexican species of Oragua Melichar, 1926 (O. balamisp. nov.) is described and illustrated from the Yucatán Peninsula based on specimens collected in Campeche (Campeche City and Castamay) and Yucatán (Ticul and Oxkutzcab) states. The new species is distinguished from other Neotropical species by the following combination of features: body color pale with orange marks on dorsum, head produced with anterior margin broadly rounded; pronotum narrower than head; forewing mottled with large orange spots; abdomen with inconspicuous apodemes; pygofer without appendages and dense long stout macrosetae over surface; aedeagus small, bulbous with one pair of twisted paraphyses with asymmetrical spines. A distribution map of available records of Oragua species recorded from southeastern Mexico is provided and a key to Mexican species is given. [ABSTRACT FROM AUTHOR]

Climate extremes and biotic interactions at the neighbourhood scale affect tropical forest dynamics with long‐term consequences for biodiversity, global carbon cycling and climate change mitigation. However, forest disturbance may change crowding intensity, and thus the relative contribution of climate extremes and neighbourhood interactions on tree growth, thereby influencing tropical forest resistance and resilience to climate change. Here, we aim to evaluate the separate and interactive effects of climate and neighbours on tree growth in old‐growth and disturbed tropical forests.We used 30 years of growth measurements for over 300 tropical tree species from 15 forest plots in French Guiana to investigate the separate and interactive effects of climate anomalies (in solar radiation, maximum temperature, vapour pressure deficit and climatic water deficit) and neighbourhood crowding on individual tree growth. Contrasting old‐growth and selectively logged forests, we also examined how disturbance history affects tree growth sensitivity to climate and neighbours. Finally, for the most abundant 100 species, we evaluated the role of 12 functional traits pertaining to water relations, light and carbon use in mediating tree growth sensitivity to climate anomalies, neighbourhood crowding and their interactions.Climate anomalies tied to heat and drought stress and neighbourhood crowding independently reduced tree growth, and showed positive interactive effects which attenuated their separate effects on tree growth. Their separate and interactive effects were stronger in disturbed than undisturbed forests. Fast‐growing species (i.e. higher intrinsic growth rates) were more abundant in disturbed forests and more sensitive to climate anomalies and neighbourhood crowding. Traits related to water relations, light and carbon use captured species sensitivities to different climate anomalies and neighbourhood crowding levels but were weak predictors of their interactions.Synthesis: Our results demonstrate that climate anomalies and neighbourhood crowding can interact to shape tropical tree growth, suggesting that considering the biotic context may improve predictions of tropical forest dynamics facing altered climate regimes. Furthermore, species traits can capture tree growth sensitivity to the separate effects of climate and neighbours, suggesting that better representing leading functional dimensions in tropical tree strategies offers a promising way towards a better understanding of the underlying ecological mechanisms that govern tropical forest dynamics. [ABSTRACT FROM AUTHOR]

Insect herbivory can be an important selective pressure and contribute substantially to local plant richness. As herbivory is the result of numerous ecological and evolutionary processes, such as complex insect population dynamics and evolution of plant antiherbivore defenses, it has been difficult to predict variation in herbivory across meaningful spatial scales. In the present work, we characterize patterns of herbivory on plants in a species‐rich and abundant tropical genus (Piper) across forests spanning 44° of latitude in the Neotropics. We modeled the effects of geography, climate, resource availability, and Piper species richness on the median, dispersion, and skew of generalist and specialist herbivory. By examining these multiple components of the distribution of herbivory, we were able to determine factors that increase biologically meaningful herbivory at the upper ends of the distribution (indicated by skew and dispersion). We observed a roughly twofold increase in median herbivory in humid relative to seasonal forests, which aligns with the hypothesis that precipitation seasonality plays a critical role in shaping interaction diversity within tropical ecosystems. Site level variables such as latitude, seasonality, and maximum Piper richness explained the positive skew in herbivory at the local scale (plot level) better for assemblages of Piper congeners than for a single species. Predictors that varied between local communities, such as resource availability and diversity, best explained the distribution of herbivory within sites, dampening broad patterns across latitude and climate and demonstrating why generalizations about gradients in herbivory have been elusive. The estimated population means, dispersion, and skew of herbivory responded differently to abiotic and biotic factors, illustrating the need for careful studies to explore distributions of herbivory and their effects on forest diversity. [ABSTRACT FROM AUTHOR]

This study presents morphological descriptions and ecological information for 58 terrestrial pollen taxa and seven water-related pollen taxa from the Brazilian Cerrado, obtained from two sediment cores, Lake Feia (LFB1) and Getulio Swamp (VGE-17), encompassing the last 5000 and 15,000 cal yr BP, respectively. The relationships between the ecological and morphological traits (pollination syndrome, vegetation stratum and grain size) within each of the two depositional environments were investigated. In the LFB1 core, the pollen assemblages were dominated by arboreal pollen from closed physiognomies and lower storey trees (<10 m in height), while a combination of closed and open physiognomies was observed in the pollen assemblages from the VGE-17 core. The vast majority of the pollen taxa exhibited the entomophilous pollination syndrome, and a higher influx of entomophilous pollen was observed in both cores. Anemophilous and anemophilous/entomophilous syndromes were less well represented. Small and medium pollen grain classes were the most abundant, while the large pollen grain class was rare. The influx of small pollen grains was slightly more abundant in the lake record, while in the swamp record medium pollen grains were more abundant. Our results show that swamps and lakes differ in their representation of local versus regional pollen and in their sensitivity and responses to water-level changes. Landscape physiognomy also influences pollen dispersion: a closed physiognomy increases the local pollen signal, while a more open physiognomy results in better representation of local and regional signals. [ABSTRACT FROM AUTHOR]

The tropical forests in the Amazon store large amounts of carbon and are still considered a carbon sink. There is evidence that deforestation can turn a forest landscape into a carbon source due to land use and forest degradation. Deforestation causes fragmented forest landscapes. It is known from field experiments that forest dynamics at the edge of forest fragments are altered by changes in the microclimate and increased tree mortality ("edge effects"). However, it is unclear how this will affect large fragmented forest landscapes, and thus the entire Amazon region. The aim of this study is to investigate different forest attributes in edge and core forest areas at high resolution, and thus to identify the large-scale impacts of small-scale edge effects. Therefore, a well-established framework combining forest modelling and lidar-generated forest structure information was combined with radar-based forest cover data. Furthermore, forests were also analyzed at the landscape level to investigate changes between highly fragmented and less-fragmented landscapes. This study found that the aboveground biomass in forest edge areas is 27% lower than in forest core areas. In contrast, the net primary productivity is 13% higher in forest edge areas than in forest core areas. In the second step, whole fragmented landscapes were analyzed. Nearly 30% of all forest landscapes are highly fragmented, particularly in the regions of the Arc of Deforestation, on the edge of the Andes and on the Amazon river banks. Less-fragmented landscapes are mainly located in the central Amazon rainforest. The aboveground biomass is 28% lower in highly fragmented forest landscapes than in less-fragmented landscapes. The net primary productivity is 13% higher in highly fragmented forest landscapes than in less-fragmented forest landscapes. In summary, fragmentation of the Amazon rainforest has an impact on forest attributes such as biomass and productivity, with mostly negative effects on forest dynamics. If deforestation continues and the proportion of highly fragmented forest landscapes increase, the effect may be even more intense. By combining lidar, radar and forest modelling, this study shows that it is possible to map forest structure, and thus the degree of forest degradation, over a large area and derive more detailed information about the carbon dynamics of the Amazon region. [ABSTRACT FROM AUTHOR]

This study utilized a remotely sensed dataset with a high spatial resolution of 3 m to predict species diversity in the Bobiri Forest Reserve (BFR), a moist semi-deciduous tropical forest in Ghana. We conducted a field campaign of tree species measurements to achieve this objective for species diversity estimation. Thirty-five field plots of 50 m × 20 m were established, and the most dominant tree species within the forest were identified. Other measurements, such as diameter at breast height (DBH ≥ 5 cm), tree height, and each plot's GPS coordinates, were recorded. The following species diversity indices were estimated from the field measurements: Shannon–Wiener (H′), Simpson diversity index (D2), species richness (S), and species evenness (J′). The PlanetScope surface reflectance data at 3 m spatial resolution was acquired and preprocessed for species diversity prediction. The spectral/pixel information of all bands, except the coastal band, was extracted for further processing. Vegetation indices (VIs) (NDVI—normalized difference vegetation index, EVI—enhanced vegetation index, SRI—simple ratio index, SAVI—soil adjusted vegetation index, and NDRE—normalized difference red edge index) were also calculated from the spectral bands and their pixel value extracted. A correlation analysis was then performed between the spectral bands and VIs with the species diversity index. The results showed that spectral bands 6 (red) and 2 (blue) significantly correlated with the two main species diversity indices (S and H′) due to their influence on vegetation properties, such as canopy biomass and leaf chlorophyll content. Furthermore, we conducted a stepwise regression analysis to investigate the most important spectral bands to consider when estimating species diversity from the PlanetScope satellite data. Like the correlation results, bands 6 (red) and 2 (blue) were the most important bands to be considered for predicting species diversity. The model equations from the stepwise regression were used to predict tree species diversity. Overall, the study's findings emphasize the relevance of remotely sensed data in assessing the ecological condition of protected areas, a tool for decision-making in biodiversity conservation. [ABSTRACT FROM AUTHOR]

Natural forest cover in Sabah has been decreasing across all forest types for more than two decades since the 1990s, being replaced mostly by man-made forests. This contributes to the overall degradation of the forest ecosystem, which changes soil nutrient content and subsequently modifies forest species composition, as well as vegetation structure. This study investigated the association between soil nutrients and tree species in unlogged and logged tropical lowland forests in Sabah, Borneo, Malaysia. A total of eight and 27 sampling plots were established in randomly placed locations at the Danum Valley Conservation Area representing the unlogged site, as well as the Sapat Kalisun area of the Ulu Segama Forest Complex representing the logged site. Soil samples at two depths (0-5 cm; 5-10 cm) were collected from each plot and analyzed for soil nutrients: total N, available P, inorganic N (NO3- and NH4+), exchangeable cations (K+, Ca2+, Mg2+, and Na+), exchangeable Al3+, and exchangeable acidity. Results showed that certain exchangeable cations and soil nutrient concentrations were greater in the unlogged forest compared to the logged forest except for K+, Na+, and inorganic N. Greater inorganic N concentrations were observed in the logged forest, hence suggesting a dominant shift toward inorganic N in the soil. PCA results indicated that exchangeable acidity and exchangeable Al3+ were correlated to logged forests, whereas Ca2+ and Mg2+ were associated with unlogged forests. CCA ordination showed the existence of association between specific tree species with K+, Ca2+, Mg2+, and Na+ in the unlogged forest only. Logging, to some extent, influenced the status of certain soil nutrients but their association with tree species was complex. This could be attributed to the heterogeneous habitat resulting from past logging disturbances. [ABSTRACT FROM AUTHOR]

Most studies focused on the above‐ground diversity on leaf litter decomposition and soil respiration in tropical ecosystems, however, the mechanism understanding of root diversity on decomposition is still unclear.We selected the fine‐roots of 21 dominant tree species from a tropical rainforest in Xishuangbannan, China, then conducted a 360‐day and well‐replicated (21 replications) incubation decomposition experiment with a 0, 1, 3, 6, 9, 12, 15, 18 and 21 species gradient of root diversity. The fine‐root mass loss, CO2 release, and their potential drivers were analysed.The results showed that as fine‐root diversity increased, soil properties, microbial diversity and fungal biomass changed nonlinearly, leading to higher litter mass loss and soil CO2 release in the moderate diversity with 9, 12 and 15 species mixtures. Non‐additive effect analysis also indicated that synergistic effects were greater in these three mixtures than others on soil CO2 release and litter mass loss. The indirect effects of soil properties and microbial communities were larger than the direct effect of fine‐root diversity.Our findings suggest that fine‐root diversity has nonlinear relationships with litter decomposition and soil CO2 release in tropical forests, thus highlighting the importance of plant diversity due to its role in the carbon cycle under global change scenario. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Question: Drought‐induced tree mortality has been documented in forests worldwide but the mechanisms related to drought recovery are still poorly understood. To better predict forest trajectories under future climate scenarios, it is essential to disentangle physiological mechanisms underlying plant mortality caused by El Niño droughts. Here, we assessed how vegetation structure, vapor pressure deficit (VPD), and functional traits interact to mediate tree mortality after a severe drought in a tropical forest. Location: Mata das Flores State Park, an Atlantic Forest fragment in southeast Brazil. Methods: We established 20 permanent plots with contrasting vegetation structure and topography. In each plot, we measured tree abundance and diameter at breast height (DBH) of every woody plant (1–10 cm diameter) at the end of the drought, and two years after the break of drought, to calculate mortality rates during drought recovery. Hydraulic (e.g., maximum stomatal conductance to water vapor, stomatal density, etc.) and economic traits (specific leaf area, wood density, etc.) were measured on the 10 most abundant species. We also measured local air temperature and air humidity using HOBO dataloggers in each plot to calculate the VPD. Results: The studied Atlantic Forest understorey did not recover from the 2014–2016 drought, in terms of tree mortality. Lower VPD, driven by big trees in the valley, protected understorey plants with acquisitive economic attributes and conservative hydraulic attributes against mortality. On the other hand, higher VPD, driven by smaller trees and higher stem density on the ridge and slope, increased the mortality of understorey plants with acquisitive attributes. Conclusion: Ridges represent the most important fraction of the Atlantic Forest and our results suggest this type of forest is at high climate risk due to global change. Altogether, our results highlight that valleys are microclimate refuges for understorey plants and might help mitigate drought impacts in tropical forest under forecasted climate changes. [ABSTRACT FROM AUTHOR]

A systematic understanding of the variation in species composition across time and space is urgently needed to protect threatened Brazilian forests.This study has disentangled the among‐site variation in beta diversity among scorpion assemblages from the Caatinga and Atlantic Forest. We calculated the relative contribution of species replacement and differences in species richness in explaining the beta diversity in each forest, correlating such metrics with environmental characteristics. Finally, we estimated the relative site‐specific contribution to identify potential environmental drivers determining unique combinations of species composition.The average among‐site dissimilarity in scorpion assemblages was higher in the Caatinga than that in the Atlantic Forest. The differences in species composition among Caatinga sites were mainly due to the spatial replacement of species. Differences in species richness at the local scale explained most of the variation in species composition among Atlantic Forest sites.Environmental variables related to topography and land use partially explained the variation in among‐site dissimilarity, species replacement, differences in species richness and the ecological uniqueness in terms of species composition in the Caatinga. Environmental variables describing topography and land use were also important in explaining differences in species richness and local contributions to the beta diversity among Atlantic Forest sites. The relative site‐specific contribution to beta diversity was higher in Caatinga sites located in ecotonal zones and Atlantic Forest sites situated within conservation reserves.Using scorpions as biological models, we have demonstrated that the species composition does not vary in a consistent way between different forest types. [ABSTRACT FROM AUTHOR]

The study explored the dependence of the spatio-temporal pattern of rainfall and its variability on the spatial distribution of forests in the central Indian landscape, which covers ~1 million km2, includes five states, and supports a population of 329 million people. The monsoon rainfall is, thus, a crucial source of freshwater for these population. We analyzed the relationship between rainfall and satellite-derived vegetation vigor, vegetation fraction, and elevation across 22 experimental zones across central India (i.e., forested, non-forested, and agricultural regions; buffer zones within and outside forests). Around 87% of annual rainfall is received during the monsoon, with maximum rainfall (~1600 mm) in Odisha and minimum (~900 mm) in Maharashtra. The average rainfall was greater (~1500 mm) inside forests than in non-forested regions (~1000 mm). Moreover, 245 mm km−2 year−1 of rainfall was observed over forests during monsoon, but only 215 mm km−2 year−1 in non-forested areas. Overall, rainfall increases from the forest edge towards the forest core logarithmically at a rate of ~10 mm km−1 year−1, and it decreases exponentially when moving away from the forest edge at an average rate of −20 mm km−1 year−1 over 0-to-50 km range, and at a rate of −7.5 mm km−1 year−1 over the 50-to-100 km range. This rate of decrease was maximum in Madhya Pradesh and Jharkhand and minimum in Chhattisgarh. The results confirmed the crucial role of forests in the distribution of monsoon rainfall, but in the elevated and Western Ghats regions, the orographic effect is dominant. These findings are of great concern to forest policymakers to conserve and protect the central Indian forests. [ABSTRACT FROM AUTHOR]

Palms (Arecaceae) exert great relevance to the structure and functioning of tropical forest ecosystems, in addition to comprise key resources for frugivorous animals. However, many species are currently at risk of extinction due to overexploitation and/or habitat loss. Our study aimed to perform a systematic review with a scientometric approach of all 78 native palm species of the Brazilian Atlantic Forest, seeking to identify the best‐studied species and regions, main studied topics, overall patterns, trends and gaps in scientific research associated with this botany family. In total, studies were carried out for 48 species belonging to 10 genera, with the number of studies exponentially increasing from the 70s and exhibiting great difference in the number of publications among species. Euterpe edulis was the most studied species (n = 274), followed by Acrocomia aculeata (n = 205), whereas Bactris bahiensis (1), Geonoma litoralis (1), Syagrus santosii (1) and Trithrinax acanthocoma (0) comprised the less studied species. The largest number of studies was carried out in the south‐eastern states of Brazil. Regarding the type of studies, 34% and 27% were related to biochemical properties and ecological processes, respectively, while studies on entomology (n = 26), tissue culture (n = 23) and taxonomy (n = 7) showed the lowest number of studies. Given the key role of palms in tropical forests, our study suggests that future research should focus on less studied species, including Desmoncus spp., Geonoma spp. and Trithrinax sp., and on some less studied areas like the north‐east portion of the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Information on tropical Asian vertebrates has traditionally been sparse, particularly when it comes to cryptic species inhabiting the dense forests of the region. Vertebrate populations are declining globally due to land‐use change and hunting, the latter frequently referred as "defaunation." This is especially true in tropical Asia where there is extensive land‐use change and high human densities. Robust monitoring requires that large volumes of vertebrate population data be made available for use by the scientific and applied communities. Camera traps have emerged as an effective, non‐invasive, widespread, and common approach to surveying vertebrates in their natural habitats. However, camera‐derived datasets remain scattered across a wide array of sources, including published scientific literature, gray literature, and unpublished works, making it challenging for researchers to harness the full potential of cameras for ecology, conservation, and management. In response, we collated and standardized observations from 239 camera trap studies conducted in tropical Asia. There were 278,260 independent records of 371 distinct species, comprising 232 mammals, 132 birds, and seven reptiles. The total trapping effort accumulated in this data paper consisted of 876,606 trap nights, distributed among Indonesia, Singapore, Malaysia, Bhutan, Thailand, Myanmar, Cambodia, Laos, Vietnam, Nepal, and far eastern India. The relatively standardized deployment methods in the region provide a consistent, reliable, and rich count data set relative to other large‐scale pressence‐only data sets, such as the Global Biodiversity Information Facility (GBIF) or citizen science repositories (e.g., iNaturalist), and is thus most similar to eBird. To facilitate the use of these data, we also provide mammalian species trait information and 13 environmental covariates calculated at three spatial scales around the camera survey centroids (within 10‐, 20‐, and 30‐km buffers). We will update the dataset to include broader coverage of temperate Asia and add newer surveys and covariates as they become available. This dataset unlocks immense opportunities for single‐species ecological or conservation studies as well as applied ecology, community ecology, and macroecology investigations. The data are fully available to the public for utilization and research. Please cite this data paper when utilizing the data. [ABSTRACT FROM AUTHOR]

Increasing urban expansion has resulted in the decline of many natural and seminatural communities globally. However, the connectivity and genetic structure of species that survive in these urban landscapes have received little attention, especially with regard to epiphytic plants. This study aimed to describe and evaluate the connectivity and genetic structure of populations of Tillandsia recurvata , a highly abundant and widely distributed atmospheric epiphyte, amongst urban green spaces within a city. A total of 288 T. recurvata individuals were sampled across 65 trees throughout the city of Alfenas in South-East Brazil. We designed seven novel microsatellite markers and used four cross-amplified loci to determine the basic genetic structure of T. recurvata. All populations showed high global spatial genetic structure, which indicated low connectivity between urban populations. The findings of this study, as well as evidence from previous assessments of T. recurvata genetic structure, suggest that the combined effects of genetic drift, breeding system, and dispersal may have dictated the connectivity of these urban populations. This study represents an important step towards understanding epiphyte population structure within urban landscapes. Low connectivity across urban landscapes is likely to benefit epiphytes such as T. recurvata , due to their adaptability and high tolerance; this suggests a bleak future for many other more sensitive epiphytic species under predicted urbanization globally. [ABSTRACT FROM AUTHOR]

Collaborations between ecosystem ecologists and engineers have led to impressive progress in developing complex models of biogeochemical fluxes in response to global climate change. Ecology and engineering iteratively inform and transform each other in these efforts. Nested data streams from local sources, adjacent networks, and remote sensing sources together magnify the capacity of ecosystem ecologists to observe systems in near real-time and address questions at temporal and spatial scales that were previously unobtainable. We describe our research experiences working in a Costa Rican rainforest ecosystem with the challenges presented by constant high humidity, 4300 mm of annual rainfall, flooding, small invertebrates entering the tiniest openings, stinging insects, and venomous snakes. Over the past two decades, we faced multiple challenges and learned from our mistakes to develop a broad program of ecosystem research at multiple levels of integration. This program involved integrated networks of diverse sensors on a series of canopy towers linked to multiple belowground soil sensor arrays that could transport sensor data streams from the forest directly to an off-site location via a fiber optic cable. In our commentary, we highlight three components of our work: (1) the eddy flux measurements using canopy towers; (2) the soil sensor arrays for measuring the spatial and temporal patterns of CO2 and O2 fluxes at the soil–atmosphere interface; and (3) focused investigations of the ecosystem impact of leaf-cutter ants as "ecosystem engineers" on carbon fluxes. [ABSTRACT FROM AUTHOR]

Previous work indicates that tropical forest can exist as an alternative stable state to savanna. Therefore, perturbation by climate change or human impact may lead to crossing of a tipping point beyond which there is rapid forest dieback that is not easily reversed. A hypothesized mechanism for such bistability is feedback between fire and vegetation, where fire spreads as a contagion process on grass patches. Theoretical models have largely implemented this mechanism implicitly, by assuming a threshold dependence of fire spread on flammable vegetation. Here, we show how the nonlinear dynamics and bistability emerge spontaneously, without assuming equations or thresholds for fire spread. We find that the forest geometry causes the nonlinearity that induces bistability. We demonstrate this in three steps. First, we model forest and fire as interacting contagion processes on grass patches, showing that spatial structure emerges due to two counteracting effects on the forest perimeter: forest expansion by dispersal and forest erosion by fires originating in adjacent grassland. Then, we derive a landscape-scale balance equation in which these two effects link forest geometry and dynamics: Forest expands proportionally to its perimeter, while it shrinks proportionally to its perimeter weighted by adjacent grassland area. Finally, we show that these perimeter quantities introduce nonlinearity in our balance equation and lead to bistability. Relying on the link between structure and dynamics, we propose a forest resilience indicator that could be used for targeted conservation or restoration. [ABSTRACT FROM AUTHOR]

Metabolomics provides an unprecedented window into diverse plant secondary metabolites that represent a potentially critical niche dimension in tropical forests underlying species coexistence. Here, we used untargeted metabolomics to evaluate chemical composition of 358 tree species and its relationship with phylogeny and variation in light environment, soil nutrients, and insect herbivore leaf damage in a tropical rainforest plot. We report no phylogenetic signal in most compound classes, indicating rapid diversification in tree metabolomes. We found that locally co‐occurring species were more chemically dissimilar than random and that local chemical dispersion and metabolite diversity were associated with lower herbivory, especially that of specialist insect herbivores. Our results highlight the role of secondary metabolites in mediating plant–herbivore interactions and their potential to facilitate niche differentiation in a manner that contributes to species coexistence. Furthermore, our findings suggest that specialist herbivore pressure is an important mechanism promoting phytochemical diversity in tropical forests. [ABSTRACT FROM AUTHOR]

Biogeochemical niche (BN) hypothesis aims to relate species/genotype elemental composition with its niche based on the fact that different elements are involved differentially in distinct plant functions. We here test the BN hypothesis through the analysis of the 10 foliar elemental concentrations and 20 functional‐morphological of 60 tree species in a French Guiana tropical forest. We observed strong legacy (phylogenic + species) signals in the species‐specific foliar elemental composition (elementome) and, for the first time, provide empirical evidence for a relationship between species‐specific foliar elementome and functional traits. Our study thus supports the BN hypothesis and confirms the general niche segregation process through which the species‐specific use of bio‐elements drives the high levels of α‐diversity in this tropical forest. We show that the simple analysis of foliar elementomes may be used to test for BNs of co‐occurring species in highly diverse ecosystems, such as tropical rainforests. Although cause and effect mechanisms of leaf functional and morphological traits in species‐specific use of bio‐elements require confirmation, we posit the hypothesis that divergences in functional‐morphological niches and species‐specific biogeochemical use are likely to have co‐evolved. [ABSTRACT FROM AUTHOR]

Restoration is fundamentally a hopeful intervention that can meaningfully improve the condition of human‐degraded and destroyed ecosystems. Both restoration science and practice have gained special attention given the recently declared UN Decade of Ecosystem Restoration. Here, we present an overview of the historical development of forest restoration on the Brazilian Atlantic Forest with an emphasis in methodological and technical assumptions. We gathered information from primary and secondary studies to show how forest restoration concepts and strategies evolved over the years. Given the importance of reviews for informing management and policy as well as research, our study provides a summarized information on forest restoration approaches or practices that can help practitioners and non‐initiated to understand how this field evolved in Brazil and how lessons learned can be useful for forest restoration in other countries. [ABSTRACT FROM AUTHOR]

The use of 3D (three-dimensional) scanning in calculating tree's volume is discussed and suitable equations are fitted for estimating stand volume based on stem diameter at breast height (DBH) and height in the form of power and logarithmic functions. One hundred eighty-four individuals of Hopea odorata, Dipterocarpus alatus and Afzelia xylocarpa were scanned. Then, 3D images were used to calculate an individual tree's volume, based on sectioning the main stem and branches by assuming the cylinder of each section. The results indicated that 3D image calculations underestimated volume by 2.1-4.8% compared to the water displacement method by testing spiral branches of 4.3-15.7 cm diameter. The logarithmic function is the best-fitted model for each species and the combination of three species. A. alatus, H. odorata and combination of three species require both DBH and height, while A. xylocarpa needs only DBH in volume estimation. All four best fitted equations have Adjusted R-Squared >0.88 and underestimate <0.9% 3D volume. The smallest underestimate of 0.02% 3D volume belongs to the best-fitted equation for combination of three species, indicating the potentiality of using a combination of three species equation for estimating the volume of all species, especially in natural forests. It is concluded the suitability of using the 3D scanning technique for calculating individual tree's volume with high accuracy and establishing volume equations for multiple species applications, especially in the tropical forest. [ABSTRACT FROM AUTHOR]

This article is a Commentary on Kullberg et al. (2024), 241: 1447–1463. [ABSTRACT FROM AUTHOR]

We compared species richness, relative abundance, density (ind/100 m2) and biomass per hectare (g/ha) of leaf-litter anurans between forest and restinga habitats in an insular Atlantic Forest area in southeastern Brazil. The local assemblage of leaf litter anurans was composed by nine species (eight of them occurring in the forest and six in the restinga), of which the most abundant were Ischnocnema parva and Adenomera marmorata in the forest, and I. parva and Dendrophryniscus lauroi in the restinga. The estimated local density of leaf-litter anurans was 11.7 ind/100m² (biomass per hectare = 848.4 g/ha) in forest and 7.3 ind/100m² in restinga (biomass per hectare = 262.8 g/ha). Anuran species richness, estimated densities and biomass in the restinga were lower than that of the forest, probably due to the less favorable environmental conditions of restingas for amphibians. [ABSTRACT FROM AUTHOR]

Flowering and fruiting phenology have been infrequently studied in the ever‐wet hyperdiverse lowland forests of northwestern equatorial Amazonía. These Neotropical forests are typically called aseasonal with reference to climate because they are ever‐wet, and it is often assumed they are also aseasonal with respect to phenology. The physiological limits to plant reproduction imposed by water and light availability are difficult to disentangle in seasonal forests because these variables are often temporally correlated, and both are rarely studied together, challenging our understanding of their relative importance as drivers of reproduction. Here we report on the first long‐term study (18 years) of flowering and fruiting phenology in a diverse equatorial forest, Yasuní in eastern Ecuador, and the first to include a full suite of on‐site monthly climate data. Using twice monthly censuses of 200 traps and >1000 species, we determined whether reproduction at Yasuní is seasonal at the community and species levels and analyzed the relationships between environmental variables and phenology. We also tested the hypothesis that seasonality in phenology, if present, is driven primarily by irradiance. Both the community‐ and species‐level measures demonstrated strong reproductive seasonality at Yasuní. Flowering peaked in September–November and fruiting peaked in March–April, with a strong annual signal for both phenophases. Irradiance and rainfall were also highly seasonal, even though no month on average experienced drought (a month with <100 mm rainfall). Flowering was positively correlated with current or near‐current irradiance, supporting our hypothesis that the extra energy available during the period of peak irradiance drives the seasonality of flowering at Yasuní. As Yasuní is representative of lowland ever‐wet equatorial forests of northwestern Amazonía, we expect that reproductive phenology will be strongly seasonal throughout this region. [ABSTRACT FROM AUTHOR]

Agricultural expansion is one of the main drivers of global pollinator loss. Paradoxically, this occurs while agriculture is becoming increasingly dependent on biotic pollination, raising concerns about food production. Integrated Crop Pollination (ICP), the use of both wild and managed pollinators in crop fields, can help conserve pollinator diversity while ensuring effective pollination services for growers. However, given the context‐dependent nature of this approach, there is an urgent need to evaluate its application across different landscapes and crops.We apply the ICP approach to açaí palm (Euterpe oleracea Mart.) production in the eastern Brazilian Amazon to explore effects of a native stingless bee, Scaptotrigona aff. postica (Apidae: Meliponini), and landscape‐level forest conservation on yield and socioeconomic outcomes for açaí fruit growers. We assessed flower visitor assemblages and fruit production on 18 plantations across a landscape forest cover gradient, with bee colonies introduced on nine plantations. Field data were combined with information from semistructured interviews of growers to estimate yield and profit per hectare under different pollinator management scenarios.Bee colonies and forest cover enhanced flower visitor abundance on palm inflorescences, but abundance increases attributed to managed bees were associated with shifts in flower visitor evenness and diversity (species richness), due to reduced visitation of wild bees near managed colonies.Fruit production on inflorescences was positively related to bee abundance and bee diversity. Consequently, overall pollination performance was lower in plantations with bee colonies. This was repeated at the hectare scale, where yield and profit were associated with surrounding forest cover and not bee colonies.Synthesis and applications. Managed bees can increase pollinator densities and fruit production, but the increased environmental and socioeconomic risks associated with this activity means açaí growers should prioritise forest conservation to safeguard pollination services and improve overall sustainability of açaí production in the eastern Brazilian Amazon. [ABSTRACT FROM AUTHOR]

At the global level, ecological restoration is becoming increasingly important due to the degraded conditions of ecosystems, which requires urgent efforts to recover these ecosystems and reestablish ecosystem services and forest biodiversity. However, there is a scarcity of studies evaluating the effects of forest restoration programs on soil properties and ecohydrological functioning of tropical ecosystems, which are in rapid decline. This research aims to evaluate ecohydrological processes in two low montane moist forest (bh-MB) watersheds subjected to ecological restoration (El Silencio and Montañita), compared to one with pastures (Pastos), and to characterize the variables influencing these processes in emerging ecosystems. In each watershed, climatic variables were monitored, and the physical, hydraulic and organic matter properties of the soil were measured, along with ecohydrological variables. The results indicate that watersheds under the restoration program exhibit a tendency to recover the initial conditions of soil properties, favoring the regulation of summer flows and reducing storm flows. In contrast, the pasture watershed shows a tendency towards degraded soils. The natural regeneration process of the forest in areas dedicated to extensive cattle raising contributes to improving the physical conditions of the soil. This improvement, in turn, facilitates water recharge to the aquifers and sustains the base flow during periods of low precipitation. [ABSTRACT FROM AUTHOR]