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ABSTRACT Extreme climatic events are expected to increase in frequency and severity under climate change, with lasting consequences for ecological communities worldwide. Global insect declines have raised concerns for biodiversity conservation and ecosystem stability, as shifts in insect communities can trigger cascading effects across trophic levels. Yet insect responses to large‐scale disturbances remain poorly understood, particularly in tropical forests where long‐term datasets are scarce and taxonomic knowledge is limited. We examined the response trajectories and stability of moth communities in two forest types in Puerto Rico following the September 2017 hurricanes Irma and María. Using monthly surveys conducted 5 months before and 6 months after the storms, followed by annual surveys over 5 years, we tracked changes in moth abundance, richness, and composition. We also evaluated ecological stability across multiple dimensions (i.e., resistance, resilience, recovery, and temporal stability) for the entire community and separately for Crambidae, Erebidae, and Geometridae. Despite initial declines, abundance and richness surpassed baseline levels within the first year, especially in old‐growth tabonuco stands, which may have provided more stable microhabitats and resources than palm stands. Resistance varied by family, with grass‐feeding crambids increasing in abundance and arboreal‐feeding geometrids experiencing the greatest species loss. Abundance and richness stabilized within 2 years, likely influenced by trophic interactions that regulated insect outbreaks. Species composition continued to shift over time, reflecting ongoing reassembly, while compositional and functional stability metrics suggested recovery within 5 years. This highlights both the resilience of the moth community and the dynamic nature of post‐disturbance reassembly. Our findings underscore the value of multi‐year, post‐disturbance datasets for uncovering recovery pathways and enhancing our understanding of ecological stability. As extreme events intensify across biomes, insights into resilience dynamics will be critical for sustaining insect biodiversity and the ecological functions they provide. 

Summary Tree architecture is an important component of forest community dynamics – taller trees with larger crowns often outcompete their neighbors, but they are generally at higher risk of wind‐induced damage. Yet, we know little about wind impacts on tree architecture in natural forest settings, especially in complex tropical forests. Here, we use airborne light detection and ranging (LiDAR) and 30 yr of forest inventory data in Puerto Rico to ask whether and how chronic winds alter tree architecture.We randomly sampled 124 canopy individuals of four dominant tree species (n = 22–39). For each individual, we measured slenderness (height/stem diameter) and crown area (m²) and evaluated whether exposure to chronic winds impacted architecture after accounting for topography (curvature, elevation, slope, and soil wetness) and neighborhood variables (crowding and previous hurricane damage). We then estimated the mechanical wind vulnerability of trees.Three of four species grew significantly shorter (2–4 m) and had smaller crown areas in sites exposed to chronic winds. A short‐lived pioneer species, by contrast, showed no evidence of wind‐induced changes.We found that three species' architectural acclimation to chronic winds resulted in reduced vulnerability. Our findings demonstrate that exposure to chronic, nonstorm winds can lead to architectural changes in tropical trees, reducing height and crown areas. 

Abstract Soils are a principal global reservoir of mercury (Hg), a neurotoxic pollutant that is accumulating through anthropogenic emissions to the atmosphere and subsequent deposition to terrestrial ecosystems. The fate of Hg in global soils remains uncertain, however, particularly to what degree Hg is re-emitted back to the atmosphere as gaseous elemental mercury (GEM). Here we use fallout radionuclide (FRN) chronometry to directly measure Hg accumulation rates in soils. By comparing these rates with measured atmospheric fluxes in a mass balance approach, we show that representative Arctic, boreal, temperate, and tropical soils are quantitatively efficient at retaining anthropogenic Hg. Potential for significant GEM re-emission appears limited to a minority of coniferous soils, calling into question global models that assume strong re-emission of legacy Hg from soils. FRN chronometry poses a powerful tool to reconstruct terrestrial Hg accumulation across larger spatial scales than previously possible, while offering insights into the susceptibility of Hg mobilization from different soil environments. 

Summary Coarse roots represent a globally important belowground carbon pool, but the factors controlling coarse root decomposition rates remain poorly understood relative to other plant biomass components. We compiled the most comprehensive dataset of coarse root decomposition data including 148 observations from 60 woody species, and linked coarse root decomposition rates to plant traits, phylogeny and climate to address questions of the dominant controls on coarse root decomposition.We found that decomposition rates increased with mean annual temperature, root nitrogen and phosphorus concentrations. Coarse root decomposition was slower for ectomycorrhizal than arbuscular mycorrhizal associated species, and angiosperm species decomposed faster than gymnosperms. Coarse root decomposition rates and calcium concentrations showed a strong phylogenetic signal.Our findings suggest that categorical traits like mycorrhizal association and phylogenetic group, in conjunction with root quality and climate, collectively serve as the optimal predictors of coarse root decomposition rates.Our findings propose a paradigm of the dominant controls on coarse decomposition, with mycorrhizal association and phylogeny acting as critical roles on coarse root decomposition, necessitating their explicit consideration in Earth‐system models and ultimately improving confidence in projected carbon cycle–climate feedbacks. 

Abstract Anthropogenic disturbances alter trajectories of ecological succession, introduce spatiotemporal variability in the composition of communities, and potentially create communities that differ substantially from those prior to disturbance. Invasive species are introduced or spread by human activities, with considerable effect on native ecosystems throughout the world. We evaluate the temporal stability of woody plant metacommunity structures and the mechanisms that give rise to them in a tropical disturbance‐mediated environment. We used data collected over 20 years to (1) evaluate elements of metacommunity structure, (2) identify the gradients along which metacommunities are structured, and (3) quantify the relative contributions of environmental and spatial factors on variation in species composition. Analyses were conducted separately for combinations of life zone (areas defined by edaphic features and climate) and species origin (native versus non‐native). Native species exhibited compartmentalized structures (i.e., groups of species with similar distributions that are replaced by other such groups along a gradient), whereas non‐natives exhibited random structures. Metacommunities based on all species were consistently compartmentalized, except in dry forest, which exhibited random structure. Compartmentalized structures occurred along gradients defined by life zone and soil type, whereas no environmental factors were consistently associated with random structures. Metacommunity structure was stable through time despite a complex disturbance regime. Dry forests, which have experienced the most extensive and intensive history of anthropogenic disturbances of any life zone on Puerto Rico are characterized by degraded and fragmented landscapes, with species that do not respond to a common environmental gradient. 

Abstract Disturbances play a central role in shaping biodiversity, influencing both community structure and ecosystem function. The responses of biodiversity to disturbance are inherently multidimensional, often leading to shifts in taxonomic composition, functional traits, and evolutionary dynamics within biological communities. Unraveling these dimensions offers valuable insights into ecosystem resilience and how communities adapt under changing disturbance regimes. This study examines the immediate effects of large‐scale hurricane disturbance on the taxonomic, phylogenetic, and functional dimensions of moth biodiversity in a tropical forest. We conducted monthly moth surveys in two forest types within the Luquillo Mountains of Puerto Rico, 5 months before and 6 months after Hurricanes Irma and María (September 2017). We collected 6152 individuals from 244 species across 19 families, performed DNA barcoding for phylogenetic analysis, and classified them by functional traits such as body size, coloration, and proboscis presence. Our findings show that hurricane disturbance reduced species richness across all diversity dimensions, while functional diversity among dominant species increased, suggesting potential stabilization of ecosystem functions despite reduced richness. In addition, the hurricanes altered both taxonomic and phylogenetic composition, with smaller grass‐feeding species increasing in abundance post‐hurricane, while larger arboreal‐feeding species, especially geometrid moths, declined markedly. These shifts highlight potential effects on trophic interactions, given moths' key roles as herbivores, pollinators, and prey. Although these systems have evolved under repeated hurricane disturbances, the long‐term consequences of a changing climate remain uncertain, particularly as more frequent and severe hurricanes may reset successional pathways and hinder forest recovery. By integrating multiple dimensions of biodiversity, our study provides a more holistic understanding of the complex consequences of hurricanes on insect communities and can inform conservation strategies aimed at enhancing ecosystem resilience. 

Abstract Elevational gradients represent platforms for exploring the effects of environmental variation on biodiversity. The environmental correlates of these spatial gradients are likely to be modified during the Anthropocene, as species respond to global change drivers including warming and increased frequency of extreme events. We quantified variation in the abundance of four functional groups of canopy arthropods (i.e., folivores, sap‐suckers, detritivores, and predators), as well as in aspects of biodiversity on each of six host‐plant species along two elevational transects in the Luquillo Mountains of Puerto Rico: a mixed forest transect, traversing tabonuco, palo colorado, and elfin forests, and a palm forest transect, comprising only patches dominated by sierra palm (Prestoea acuminata). We expected gradients in arthropod abundance and biodiversity to be host‐tree specific, and for gradients on palm to differ between transects due to a combination of mechanisms associated with host selection, rescue effects, habitat structure, and source pool dynamics. In general, abundance and biodiversity declined with elevation. The ways in which abundance declined with increasing elevation was contingent on host tree identity and on arthropod functional group, whereas all aspects of biodiversity declined with elevation in consistent manners regardless of host tree identity or transect. Similarly, turnover (beta components of biodiversity between sequential elevational strata) did not differ between transects. Decreases in productivity with increasing elevation may be responsible for gradients in abundance or biodiversity. However, host‐specific and functional group‐specific gradients suggest that elevational effects manifest differently depending on tree species identity and resource bases that are consumer specific. 

Abstract Models project that climate change is increasing the frequency of severe storm events such as hurricanes. Hurricanes are an important driver of ecosystem structure and function in tropical coastal and island regions and thus impact tropical forest carbon (C) cycling. We used the DayCent model to explore the effects of increased hurricane frequency on humid tropical forest C stocks and fluxes at decadal and centennial timescales. The model was parameterized with empirical data from the Luquillo Experimental Forest (LEF), Puerto Rico. The DayCent model replicated the well-documented cyclical pattern of forest biomass fluctuations in hurricane-impacted forests such as the LEF. At the historical hurricane frequency (60 years), the dynamic steady state mean forest biomass was 80.9 ± 0.8 Mg C/ha during the 500-year study period. Increasing hurricane frequency to 30 and 10 years did not significantly affect net primary productivity but resulted in a significant decrease in mean forest biomass to 61.1 ± 0.6 and 33.2 ± 0.2 Mg C/ha, respectively (p < 0.001). Hurricane events at all intervals had a positive effect on soil C stocks, although the magnitude and rate of change of soil C varied with hurricane frequency. However, the gain in soil C stocks was insufficient to offset the larger losses from aboveground biomass C over the time period. Heterotrophic respiration increased with hurricane frequency by 1.6 to 4.8%. Overall, we found that an increasing frequency of tropical hurricanes led to a decrease in net ecosystem production by − 0.2 ± 0.08 Mg C/ha/y to − 0.4 ± 0.04 Mg C/ha/y for 30–10-year hurricane intervals, respectively, significantly increasing the C source strength of this forest. These results demonstrate how changes in hurricane frequency can have major implications for the tropical forest C cycle and limit the potential for this ecosystem to serve as a net C sink. 

Abstract Background and AimsUnderstanding shifts in the demographic and functional composition of forests after major natural disturbances has become increasingly relevant given the accelerating rates of climate change and elevated frequency of natural disturbances. Although plant demographic strategies are often described across a slow–fast continuum, severe and frequent disturbance events influencing demographic processes may alter the demographic trade-offs and the functional composition of forests. We examined demographic trade-offs and the shifts in functional traits in a hurricane-disturbed forest using long-term data from the Luquillo Forest Dynamics Plot (LFPD) in Puerto Rico. MethodsWe analysed information on growth, survival, seed rain and seedling recruitment for 30 woody species in the LFDP. In addition, we compiled data on leaf, seed and wood functional traits that capture the main ecological strategies for plants. We used this information to identify the main axes of demographic variation for this forest community and evaluate shifts in community-weighted means for traits from 2000 to 2016. Key ResultsThe previously identified growth–survival trade-off was not observed. Instead, we identified a fecundity–growth trade-off and an axis representing seedling-to-adult survival. Both axes formed dimensions independent of resprouting ability. Also, changes in tree species composition during the post-hurricane period reflected a directional shift from seedling and tree communities dominated by acquisitive towards conservative leaf economics traits and large seed mass. Wood specific gravity, however, did not show significant directional changes over time. ConclusionsOur study demonstrates that tree demographic strategies coping with frequent storms and hurricane disturbances deviate from strategies typically observed in undisturbed forests, yet the shifts in functional composition still conform to the expected changes from acquisitive to conservative resource-uptake strategies expected over succession. In the face of increased rates of natural and anthropogenic disturbance in tropical regions, our results anticipate shifts in species demographic trade-offs and different functional dimensions. 

Abstract Hurricanes are major disturbances with important consequences to stream ecosystems as they create major floods and remove riparian vegetation. Understanding their impacts is a priority, as hurricane intensity is expected to increase due to global climate change.Mayfly assemblages in streams fill a diversity of ecological roles and functions. They are important consumers of algae by scraping benthic biofilms and detritivores associated with fine particles and leaf litter. Other taxa are filterers and even predators. Mayflies are also important prey items in aquatic and terrestrial food webs.Here, we assessed the effects of two consecutive hurricanes that impacted Puerto Rico in 2017 to understand how hurricane‐induced changes in the environment alter mayfly composition, secondary production and emergence.The study was conducted in the Luquillo Experimental Forest, Puerto Rico. Mayflies were sampled as nymphs and emerging adults for 6 months before and 17 months after hurricanes Irma and María hit the island in September 2017. Leaf litter inputs, canopy cover and chlorophyllaconcentrations were monitored along with mayflies.Mayfly assemblages were dominated by two genera of Leptophlebiidae before the hurricane,Neohagenulus (two species: N. julioTraver, 1938,N. luteolusTraver, 1938) andBorinquena (one species: B. carmencitaTraver, 1938). Both genera decreased in density after the hurricanes and were replaced with the BaetidaeCloeodes maculipesTraver, 1938 as the dominant taxon. This pattern was observed in both nymph and emerging adult densities.The secondary production of Leptophlebiidae species was highest before hurricane disturbance, with the BaetidaeC. maculipesshowing the opposite pattern.Neohagenulushad an annual production of 445 mg m⁻² year⁻¹,C. maculipesof 153 mg m⁻² year⁻¹andB. carmencitaof 68 mg m⁻² year⁻¹.Overall, the mayfly assemblages in our studied stream are vulnerable to hurricane disturbances. Expected increases in hurricane impacts might result in assemblage shifts that could change assemblage composition and alter energy flows within the ecosystem.