Beyond species: functional diversity and the maintenance of ecological processes and services

Non-native plants tend to be phylogenetically distant but functionally similar to native plants under intense disturbance at the Three Gorges Reservoir Area

Darwin's two opposing hypotheses, proposing that non-native species closely or distantly related to native species are more likely to succeed, are known as 'Darwin's Naturalization Conundrum'. Recently, invasion ecologists have sought to unravel these hypotheses. Studies that incorporate rich observational data in disturbed ecosystems that integrate phylogenetic and functional perspectives have potential to shed light on the conundrum. Using 313 invaded plant communities including 46 invasive plant species and 531 native plant species across the Three Gorges Reservoir Area in China, we aim to evaluate the coexistence mechanisms of invasive and native plants by integrating phylogenetic and functional dimensions at spatial and temporal scales. Our findings revealed that invasive plants tended to co-occur more frequently with native plant species that were phylogenetically distant but functionally similar in the reservoir riparian zone. Furthermore, our study demonstrated that the filtering of flood-dry-flood cycles played a significant role in deepening functional similarities of native communities and invasive-native species over time. Our study highlights the contrasting effects of phylogenetic relatedness and functional similarity between invasive and native species in highly flood-disturbed habitats, providing new sights into Darwin's Naturalization Conundrum.

Assessment of habitat features modulated carbon sequestration strategies for drought management in tropical dry forest fragments

Habitat features, such as species diversity, functional diversity, tree size, disturbances and fragment sizes have differential impacts on carbon (C) storage and C-sequestration in forest ecosystems. Present study attempted to understand the tree strategies for modulating C-sequestration capacity across tropical dry forest fragments with variable edge distances. We evaluated the differences between drought strategies (i.e., drought avoiding and drought tolerant) for variations in stem density, relative growth rate (RGR), C-storage and C-sequestration, species diversity, functional diversity, tree size and disturbance indicators along edge distance gradient, besides analyzed the differences between drought strategies for responses of C-storage and C-sequestration to variations in species diversity, functional diversity, tree size and disturbance indicators. Various traits and functional indices were analyzed using standard statistical techniques. For total trees and for the two drought strategies, generalized linear modeling results showed a significant decline in stem density, RGR, C-stock, C-sequestration, species diversity, functional diversity and tree size indicators, while a considerable increase in disturbance indicators, along decreasing edge distance across the fragments. The drought strategies exhibited a high degree of variation in the slope of associations for above variables with edge distance across fragments. For predicting C-sequestration, structural equation modeling results showed highly significant influence of functional diversity indicators for drought avoiding strategy, while species diversity indicators were strongly significant for drought tolerant strategy. Moreover, fire index and drought index were critical predictors for C-sequestration for drought avoiding and drought tolerant strategies, respectively. This study provide inputs to understand the largely ignored processes of C-storage and C-sequestration in fragmented forests, which are currently prevalent due to heavy anthropogenic pressures. Our findings are useful for forest managers to understand vegetation responses to interactions of species diversity, functional diversity, tree size and disturbance indicators, for predicting the stability of larger fragments and for planning restoration of smaller fragments.

Multidimensional aspects of riverine biodiversity can vary in response to nutrient pollution and environmental dynamics across climatic watersheds

The concurrent impact of anthropogenic and bioclimatic factors on biodiversity is a key focus in macroecological and biogeographical considerations in conservation programs within riverine ecosystems. However, there is still a lack of understanding about how multidimensional alpha and beta diversity measures respond to anthropogenic and bioclimatic drivers. Here, we assess the variations in taxonomic, phylogenetic, and functional alpha and beta diversity of riverine macroinvertebrate communities across different watersheds in China. Our results show significant declines in most facets of alpha diversity across watersheds with low environmental heterogeneity, reflecting the loss of species with unique traits and evolutionary legacies. Both functional and phylogenetic beta-diversity values reveal a decreasing pattern along low heterogeneity environments, whereas taxonomic beta-diversity shows a contrasting pattern, which highlights the influence of microhabitat variation. Moreover, our findings identify nutrient levels, organic matter, water quality indicators, climatic variation, and geographic and habitat characteristics as key determinants of diversity patterns that are indicative of broader water pollution challenges. These factors jointly influence functional and phylogenetic alpha diversity and contribute to spatial homogenization, which is reflected in decreased functional and phylogenetic beta diversity. These trends highlight the complex interactions of chemical and physical factors in shaping biodiversity characteristics across watersheds. Based on the null model, macroinvertebrate communities primarily show random patterns, whereas clustering and overdispersion were sporadically observed in specific communities. We propose that conservation and restoration efforts should be aimed at enhancing aquatic biomes by managing extreme environmental conditions and amplifying spatial spillover, thereby supporting the intrinsic dynamics within natural metasystems and thus preserving the multidimensional aspects of biodiversity.

Topographic heterogeneity triggers complementary cascades that enhance ecosystem multifunctionality

Topographic heterogeneity sets the stage for community assembly, but its effects on ecosystem functioning remain poorly understood. Here, we test the hypothesis that topographic heterogeneity underpins multiple cascading species interactions and functional pathways that indirectly control multifunctionality. To do so, we combined experimental manipulation of a form of topographic heterogeneity on rocky shores (holes of various sizes) with a comprehensive assessment of naturally assembled communities and multifunctionality. Structural equation modeling indicated that heterogeneity: (1) enhanced biodiversity by supporting filter feeder richness; (2) triggered a facilitation cascade via reef-forming (polychaete) and biomass-dominant (macroalga) foundation species, which in turn broadly supported functionally diverse epibiotic and understory assemblages; and (3) inhibited a key consumer (limpet). The model supported that these mechanisms exerted complementary positive effects on individual functions (e.g., water filtration, ecosystem metabolism, nutrient uptake) and, in turn, collectively enhanced multifunctionality. Topographic heterogeneity may therefore serve as a cornerstone physical attribute by initiating multiple cascades that propagate through ecological communities via foundation species, ultimately manifesting disproportionate effects on ecosystem multifunctionality.

Taxonomic and functional diversities reveal different fish assemblage dynamics of stow net fishery in Haizhou Bay

Biodiversity is the cornerstone of marine fisheries. To ensure the prosperity of stow net fishery in Haizhou Bay, regular investigations of fishery resources are essential. However, most studies have primarily focused on taxonomic diversity while overlooking functional diversity. In this study, we examined both the taxonomic and functional diversity of fish assemblages based on abundance and functional traits from 2013 to 2018. Significant differences in taxonomic diversity were observed only between two seasons, whereas functional diversity showed significant differences across years, seasons and groups. Diversity indices exhibited negative linear relationships with catch per unit effort, except for functional evenness (FEve) and functional divergence. Twenty-seven out of 30 correlations between the two types of diversity indices were predominantly positive and synclastic, whether linear or nonlinear. Functional dispersion showed the most positive relationships with taxonomic diversities, while FEve exhibited gentle slopes. The functional redundancy curves indicated that the ecological stability and resilience of fish assemblages were vulnerable. The non-target fish group demonstrated a higher overlap in functions compared to the target fish group and the total fish group. In summary, the taxonomic and functional diversities revealed inconsistent statuses and trends of fish assemblages, with an evident decreasing trend in the non-target fish group requiring special attention. This study highlights that both taxonomic and functional diversity should be considered simultaneously in fish biodiversity investigations, which is crucial for establishing effective fish conservation systems.

Functional diversity explores the maintenance mechanism and driving factors of the invasion equilibrium state of the icefish (Neosalanx taihuensis Chen) in Lake Fuxian, China

Biodiversity loss caused by biological invasions is an ecological problem on a global scale, and understanding the mechanism of biological invasion is the basis for managing non-native species. The biotic resistance hypothesis proposes that species-rich native communities are less susceptible to invasion because of the limited resources available to non-native species, therefore comparing the resource utilization patterns of different communities can reveal the invasion mechanisms of specific non-native species at the community level. We selected Lake Taihu, where icefish (Neosalanx taihuensis Chen) originated, and Lake Fuxian, where icefish invaded, as the research objects. We calculated the fish functional diversity indexes, including functional richness (FRic), functional evenness (FEve), and functional divergence (FDiv), to reflect differences in ecological niche and resource utilization based on four quarterly fish survey data from two lakes. The random forests model explored the relationship between functional diversity indexes and biotic and environmental variables. Our results showed that more diverse resource utilization (high FRic), more niche space (low FEve), and less competitive pressure (high FDiv) in Lake Fuxian were identified as the critical important factors for maintaining the current equilibrium state after successful invasion of icefish. The bottom-up effects mainly affected the functional diversity indexes in Lake Fuxian. They differed from those in Lake Taihu and were primarily influenced by top-down effects. Enhancing the top-down effects in Lake Fuxian and limiting the zooplankton available to icefish are critical to controlling the invasion of icefish. This study offers a new perspective for studying the non-native fish invasion mechanism, and provides scientific guidance for managing non-native fish in Lake Fuxian.

Conserved responses of water use to evaporative demand in mixed forest across seasons in low subtropical China

The positive correlation between diversity and production has been extensively documented. Given the intrinsic relationship between production and plant water consumption, it was anticipated that mixed forests would exhibit different water use compared to pure forests. In this study, the responses of water use to vapour pressure deficit were analyzed by monitoring the sap flow of Schima superba in both pure and mixed forests, as well as Castanopsis chinensis in mixed forest. Additionally, the relationships among leaf and stem traits were examined by measuring specific leaf area (SLA), N and P concentration per unit leaf mass, leaf δ18O and δ13C and wood density of sapwood (WD) during both wet and dry seasons. The results showed that S. superba demonstrated a comparable regulation of water use during both wet and dry seasons in mixed forest, whereas it exhibited less strict water use regulation during the wet season in comparison to the dry season in pure forest. Regardless of whether the forests were pure or mixed, both leaf δ13C and WD remained consistent across seasons, while there was an increase in SLA during the wet season compared to the dry season for S. superba. There was a different seasonal change in leaf δ18O for S. superba in pure and mixed forests. Water use and leaf economic spectrum may determine the adaptive strategies of coexisting species, and the coexisting tree species in mixed forest exhibited a resource-use differentiation, as indicated by seasonal variations in leaf and stem traits, likely explaining the conserved responses of sap flow to evaporative demand. Our research might provide insights into the impact of tree interaction on water use strategies and the water use-based forest management under current climate change.

A bird's-eye view of avian extinctions

Conservation should consider species' functional and phylogenetic traits.

Combining citizen science data and literature to build a traits dataset of Taiwan's birds

Trait-based methodologies are gaining traction in the field of ecology, providing deeper insights into ecosystem structure and functions. To this end, trait databases tailored to specific taxonomic groups have become foundational. In Taiwan, the collaborative efforts of avian researchers and dedicated citizen scientists have led to the compilation of a vast array of data. This includes web-sourced images from social media, spatial distribution records from eBird, and morphological metrics from banded birds and specimens. Enriched by peer-reviewed literature, we have meticulously assembled a comprehensive trait dataset encompassing 454 bird species across 73 families. This dataset covers a wide range of traits, including foraging ecology, morphological characteristics, territorial behaviors, breeding attributes, and the roles of bird species in ecosystem regulation. As an invaluable resource, this dataset lays the foundation for in-depth exploration of functional diversity, trait-based community ecology, ecosystem function, and critical insights needed to shape conservation strategies.

Environmental influence on the functional ecological structure of benthic macrofaunal communities of the northwest Iberian coast

Evaluating the functional structure of benthic macrofaunal communities provides insights into how environmental drivers shape the ecosystem and establishes a baseline knowledge of the communities' dynamics and functioning. This understanding allows the prediction of responses to environmental changes and the implementation of efficient conservation and management strategies. Here we examine the structures and functions of benthic macrofaunal communities on the Northwest Iberian coast concerning environmental factors such as depth, hydrodynamic energy, and bottom type. The results suggest that the community assemblages and their function are structured by factors which influence food availability and habitat heterogeneity. The different sites exhibited different trait compositions and functional structures, indicating that distinct functions are performed according to environmental conditions. The communities found in sandy bottom areas with low hydrodynamic conditions presented frail functionality and demonstrated high vulnerability to alterations in their environment. Conversely, the communities found in rocky bottoms with high hydrodynamic conditions exhibited a fulfilled functional niche space, rendering them more resilient to such changes and less prone to loss of function. Although the analyses did not reveal significant differences in the factor depth, its influence on several factors seems relevant in shaping the functional structure of the communities. These findings highlight the importance of understanding the impact of local environmental conditions on ecosystem functioning, to effectively implement monitoring, management, and conservation strategies.

Seasonality Structures Avian Functional Diversity and Niche Packing Across North America

Assemblages in seasonal ecosystems undergo striking changes in species composition and diversity across the annual cycle. Despite a long-standing recognition that seasonality structures biogeographic gradients in taxonomic diversity (e.g., species richness), our understanding of how seasonality structures other aspects of biodiversity (e.g., functional diversity) has lagged. Integrating seasonal species distributions with comprehensive data on key morphological traits for bird assemblages across North America, we find that seasonal turnover in functional diversity increases with the magnitude and predictability of seasonality. Furthermore, seasonal increases in bird species richness led to a denser packing of functional trait space, but functional expansion was important, especially in regions with higher seasonality. Our results suggest that the magnitude and predictability of seasonality and total productivity can explain the geography of changes in functional diversity with broader implications for understanding species redistribution, community assembly and ecosystem functioning.

Combined effects of climate and land-use changes on the alpha and beta functional diversities of terrestrial mammals in China

Climate and land-use changes are predicted to impact biodiversity, threatening ecosystem services and functions. However, their combined effects on the functional diversity of mammals at the regional scale remain unclear, especially at the beta level. Here, we use projected climate and land-use changes in China to investigate their potential effects on the alpha and beta functional diversities of terrestrial mammals under low- and high-emission scenarios. In the current projection, we showed strong positive spatial correlations between functional richness and species richness. Functional evenness (FEve), functional specialization (FSpe), and functional originality (FOri) decreased with species richness, and functional divergence (FDiv) increased first and then plateaued. Functional beta diversity was dominated by its nestedness component, in contrast to the taxonomic facet. Potential changes in species richness are more strongly influenced by land-use change under the low-emission scenario, while under the high-emission scenario, they are more strongly influenced by climate change. Changes in functional richness (FRic) were inconsistent with those in species richness, with a magnitude of decreases greater than predicted from species richness. Moreover, mammal assemblages showed potential functional differentiation (FD) across the country, and the trends exceeded those towards taxonomic differentiation (TD). Our findings help us understand the processes underlying biodiversity responses to global changes on multiple facets and provide new insight for conservation plans.

Late Miocene transformation of Mediterranean Sea biodiversity

Understanding deep-time marine biodiversity change under the combined effects of climate and connectivity changes is fundamental for predicting the impacts of modern climate change in semi-enclosed seas. We quantify the Late Miocene-Early Pliocene [11.63 to 3.6 million years (Ma)] taxonomic diversity of the Mediterranean Sea for calcareous nannoplankton, dinocysts, foraminifera, ostracods, corals, molluscs, bryozoans, echinoids, fishes, and marine mammals. During this time, marine biota was affected by global climate cooling and the restriction of the Mediterranean's connection to the Atlantic Ocean that peaked with the Messinian salinity crisis. Although the net change in species richness from the Tortonian to the Zanclean varies by group, species turnover is greater than 30% in all cases, reflecting a high degree of reorganization of the marine ecosystem after the crisis. The results show a clear perturbation already in the pre-evaporitic Messinian (7.25 to 5.97 Ma), with patterns differing among groups and subbasins.

Metropolitan pressures: Significant biodiversity declines and strong filtering of functional traits in fish assemblages

Accelerating global urbanization is leading to drastic losses and restructuring of biodiversity. Although it is crucial to understand urban impacts on biodiversity to develop mitigation strategies, there is a dearth of knowledge on the functional structure of fish assemblages spanning the entire city-scale spectrum of urbanization intensity. Here, using environmental DNA sampled from 109 water sites in Beijing, we investigated the taxonomic and functional diversity patterns of fish assemblages across the city and uncovered community-, trait-, and species-level responses to various environmental stressors. By ranking sampling sites into three disturbance levels according to water physiochemical and landcover conditions, we found that both native and non-native fish taxonomic and functional α-diversity decreased significantly with elevating disturbance, as strong disturbance led to the disappearance of many species. However, the quantitative taxonomic and functional β-diversity components of native and non-native fish showed distinct patterns; assemblage turnover dominated native fish β-diversity and decreased with increasing disturbance, whereas species/trait richness differences dominated non-native fish β-diversity and increased with disturbance intensity particularly in lotic waters. RLQ and fourth-corner analyses revealed that fish size, fecundity, diet, and reproductive behaviors were significantly correlated with water quality, with pollution-tolerant, larger-sized native and omnivorous non-native fishes being urban winners, which indicates strong trait-dependent environmental filtering. Potential ecological indicator species were identified based on the sensitivity of fish responses to pollution loads; these were mostly small native species, and many have bivalve-dependent reproduction. Our results demonstrate that, along with native fish assemblage simplification and homogenization, urban stressors exert profound impacts on community trait composition, highlighting the need to consider both biodiversity loss and functional reorganization in combating disturbance of aquatic ecosystems under global urbanization. Furthermore, correlations between cropland cover and water nutrient level suggested that the management of agricultural runoff might be critically important for safeguarding urban water quality.

Application of Synchronous Evaluation-Diagnosis Model with Quantitative Stressor-Response Analysis (SED-QSR) to Urban Lake Ecological Status: A Proposed Multiple-Level System

Ecological integrity assessment and degradation diagnosis are used globally to evaluate the health of water bodies and pinpoint critical stressors. However, current studies mainly focus on separate evaluation or diagnosis, leading to an inadequate exploration of the relationship between stressors and responses. Here, based on multiple data sets in an urban lake system, a synchronous evaluation-diagnosis model with quantitative stressor-response analysis was advanced, aiming to improve the accuracy of evaluation and diagnosis. The weights for key physicochemical stressors were quantitatively determined in the sequence of NDAVIadj > CODMn > TP > NH4+-N by the combination of generalized additive model and structural equation modeling, clarifying the most significant effects of aquatic vegetation on the degradation of fish assemblages. Then, sensitive biological metrics were screened by considering the distinct contributions of four key stressors to alleviate the possible deviation caused by common methods. Finally, ecological integrity was evaluated by summing the key physicochemical stressors and sensitive biological metrics according to the model-deduced weights instead of empirical weights. Our system's diagnosis and evaluation results achieved an accuracy of over 80% when predicting anthropogenic stress and biological status, which highlights the great potential of our multiple-level system for ecosystem management.

Vertical distributions of megafauna on inactive vent sulfide features correspond to their feeding modes

The discovery of inactive hydrothermal vent sulfide features near 9°50'N on the East Pacific Rise provides an opportunity to investigate the distribution and feeding ecology of communities inhabiting this type of habitat. We quantify megafaunal distributions on two features, Lucky's Mound and Sentry Spire, to determine how taxonomic composition and feeding traits vary with vertical elevation. Fifty-one morphotypes, categorized by feeding mode, were identified from three levels of the features (spire, apron, and base) and the surrounding flat oceanic rise. About half of the morphotypes (26 of 51) were only observed at the sulfide features. Passive suspension feeders were more abundant on the spires, where horizontal particulate flux is expected to be elevated, than the base or rise. Deposit feeders tended to be more abundant on the base and rise, where deposition is expected to be enhanced, but were unexpectedly abundant higher up on Sentry Spire. Community differences between the two sulfide features suggest that other processes, such as feature-specific chemoautotrophic production, may also influence distributions.

Coupled relationships between landscape pattern and ecosystem health in response to urbanization

Rapid urbanization has highlighted ecological problems in the metropolitan area, with increasing landscape fragmentation and severe threats to ecosystem health (EH). Studying the spatio-temporal coupled relationship between landscape pattern and EH and its response to urbanization in the Fuzhou metropolitan area (FMA) can provide scientific reference for its long-term development planning. We examined the coupled relationship between landscape pattern and EH and its driving mechanism in the FMA at grid and township scales to address the gap. The results show that landscape heterogeneity, diversity, and dispersion are gradually increasing, and EH is rising progressively in the FMA from 2000 to 2020. The spatial distribution of landscape pattern indices and EH indicators showed a "high in the south and low in the north" trend. During the study period, the coupled relationship between landscape patterns and EH was increasingly powerful but with remarkable spatial heterogeneity. The study also found an inverted U-shaped relationship between urbanization and coupled relationships. Ecological landscapes' heterogeneity, diversity, and connectivity in low-urbanization areas are conducive to EH. The opposite is true for high-urbanization areas. This study provides a valuable reference for optimizing landscape planning and ecological management in metropolitan areas.

Spatial patterns of congruence or mismatch between taxonomic, functional, and phylogenetic diversity and endemism of perennial flora along the aridity gradient of Chile

Introduction

Understanding the relationships between taxonomic, functional, and phylogenetic diversity and endemism across environmental gradients is essential for elucidating the eco-evolutionary mechanisms that shape local plant communities.

Methods

A database was compiled from field surveys, national herbarium records, and virtual records of perennial plant specimens collected in the aridity gradient of northern Chile, between 18 and 32°S. A large-scale dated phylogeny of available perennial plants was used, and 11 functional traits were selected to construct a dendrogram using the Unweighted Pair-Group Method with Arithmetic Mean (UPGMA) method for the species present in our database. We calculated spatial patterns of a-diversity, including taxonomic (TD), functional (FD), and phylogenetic (PD) diversity, as well as weighted (WE), functional (FE), and phylogenetic (PE) endemism. We used multiscale geographically weighted regression (MGWR) to identify spatial congruencies and discrepancies among these dimensions and to test different eco-evolutionary processes.

Results

The diversity indices TD, FD and PD showed similar geographic patterns (R2 > 0.93), with lower diversity observed in absolute desert regions. The pattern of weighted endemism (WE) showed a weak association with functional endemism (FE) and phylogenetic endemism (PE) (local R2 < 0.48). The regions with lower FD or PD than expected given the TD (i.e. FD

Predicting avian diversity based on land use and cover on a national scale

This study explores the relationship between landscape features and avian diversity in South Korea, examining both taxonomic and functional diversity. The Korean Peninsula serves as a pivotal habitat for resident bird species and a migratory pathway in the East Asia-Pacific flyway. Using a national dataset with block sizes ranging from 3.5 to 4.5 kilometers per side, we found that less urbanized open plains exhibit higher taxonomic diversity, while coastal regions with diverse water bird populations show higher functional diversity. These findings underscore the significance of conserving the existing land types and qualities in specific regions to substantially impact bird distribution and regional biodiversity. Remarkably, closed forests display diversity patterns akin to urban/built-up areas, despite their disparate land use characteristics. The stability of bird diversity indices across different land use types enables us to predict bird diversity indices based on the particular land use and land cover configurations. This study emphasizes the complementary nature of functional biodiversity indices in comprehending bird distribution patterns alongside taxonomic diversity indices.

Functional trait mismatch between native and introduced bee pollinators servicing a global fruit crop

BACKGROUND

Understanding connections between biodiversity and ecosystem services can be enhanced by shifting focus from species richness to functional trait-based approaches, that when paired with comparative phylogenetic methods can provide even deeper insights. We investigated the functional ecology and phylogenetic diversity of pollination services provided by hymenopteran insects visiting apple flowers in orchards surrounded by either 'natural' or 'disturbed' landscapes in New South Wales, Australia. We assessed whether morphological and behavioural traits (hairiness, body size, glossa length, pollen load purity, and probability of loose pollen) exhibited non-random phylogenetic patterns. Then, explored whether bees, the primary pollinators in this system, filled unique or overlapping functional entities (FEs). For each landscape, we calculated phylogenetic diversity and used FEs to assess functional richness, evenness, and diversion.

RESULTS

A phylogenomic matrix based on ultraconserved elements (UCEs; 1,382,620 bp from 1,969 loci) was used to infer a fully-resolved and well-supported maximum likelihood phylogeny for 48 hymenopteran morphospecies. There was no significant difference in species richness between landscape categories. Pollinator communities at natural sites had higher phylogenetic complexity (X = 2.37) and functional divergence (x̄ = 0.74 ± 0.02 s.e.) than disturbed sites (X = 1.65 and x̄ = 0.6 ± 0.01 s.e.). Hairiness showed significant phylogenetic clustering (K = 0.94), whereas body size, glossa length, and loose pollen showed weaker non-random phylogenetic patterns (K between 0.3-0.5). Pollen load purity showed no association with phylogeny. The assemblage of 17 bee morphospecies comprised nine FEs: eight FEs consisted of native bees with three containing 65% of all native bee taxa. The introduced honey bee (Apis mellifera) occupied a unique FE, likely due to its different evolutionary history. Both landscape types supported six FEs each with three overlapping: two native bee FEs and the honey bee FE.

CONCLUSIONS

Bee hairiness was the only functional trait to exhibit demonstrable phylogenetic signal. Despite differences in species richness, and functional and phylogenetic diversity between orchard landscape types, both maintained equal bee FE numbers. While no native bee taxon was analogous to the honey bee FE, four native bee FEs shared the same hairiness level as honey bees. Health threats to honey bee populations in Australia will likely disrupt pollination services to apple, and other pollination-dependent food crops, given the low level of functional redundancy within the investigated pollinator assemblages.

Plant species diversity and functional diversity relations in the degradation process of desert steppe in an arid area of northwest China

Species and functional diversity play a major role in the stability and sustainability of grassland ecosystems. However, changes in species and functional diversity during grassland degradation in arid areas as well as the underlying mechanisms remain unclear. In this study, we surveyed the vegetation and soil properties of arid regions across a degradation gradient to explore the shifts in species and functional diversity in plant communities, their relationships and key determinants during desert steppe degradation. Our results found significant variability in species diversity and functional diversity across degradation stages. Species diversity (Shannon-Wiener index (H), and Pielou index) and functional diversity (functional evenness (FEve) index, and Rao's quadratic entropy (RaoQ) index) tended to increase initially and then decrease with increasing grassland degradation. The Patrick index, Simpson index, functional richness (FRic) index, functional divergence (FDiv) index, and functional dispersion (FDis) index declined as grassland degradation increased. The relationships between species diversity and functional diversity indices at different stages of degradation in the desert steppe were inconsistent. From no to heavy degradation grasslands, the correlation between species diversity and functional diversity gradually weakened. Specifically, there was a significant correlation between Patrick (R) and FRic indices (R2 > 0.7) on both non-degraded and light degraded grasslands, but there was no significant correlation between R and FRic indices in moderately and heavily degraded grasslands (R2 < 0.7), and R2 gradually decreased. Redundancy analysis and partial least squares path modeling showed that grassland degradation has a significant direct effect on the species diversity and functional diversity. In addition grassland degradation has direct and indirect effects on the species diversity through soil available nitrogen, organic matter and total nitrogen. Functional diversity is directly or indirectly affected by species diversity, soil available nitrogen, organic matter and total nitrogen, soil moisture content, soil bulk density, and pH value. In summary, the relationship between species and functional diversity indices gradually weakened from areas with no degradation to heavy degradation in arid desert grasslands. Our study reveals the patterns and relationships between species diversity and functional diversity throughout the process of grassland degradation, demonstrating a gradual decrease in ecosystem stability and sustainability as degradation advances. Our results have significant implications for the restoration of grassland degradation and the management of ecosystem services in arid steppe regions.

Species Richness Net Primary Productivity and the Water Balance Problem

Species energy theory suggests that, because of limitations on reproduction efficiency, a minimum density of plant individuals per viable species exists and that this minimum correlates the total number of plant individuals N with the number of species S. The simplest assumption is that the mean energy input per individual plant is independent of the number of individuals, making N, and thus S as well, proportional to the total energy input into the system. The primary energy input to a plant-dominated ecosystem is estimated as its Net Primary Productivity (NPP). Thus, species energy theory draws a direct correspondence from NPP to S. Although investigations have verified a strong connection between S and NPP, strong influences of other factors, such as topography, ecological processes such as competition, and historical contingencies, are also at play. The lack of a simple model of NPP expressed in terms of the principal climate variables, precipitation P, and potential evapotranspiration, PET, introduces unnecessary uncertainty to the understanding of species richness across scales. Recent research combines percolation theory with the principle of ecological optimality to derive an expression for NPP(P, PET). Consistent with assuming S is proportional to NPP, we show here that the new expression for NPP(P, PET) predicts the number of plant species S in an ecosystem as a function of P and PET. As already demonstrated elsewhere, the results are consistent with some additional variation due to non-climatic inputs. We suggest that it may be easier to infer specific deviations from species energy predictions with increased accuracy and generality of the prediction of NPP(P, PET).

Dynamic restoration mechanism of plant community in the burned area of northeastern margin of Qinghai-Tibet Plateau

Forest fires play a pivotal role in influencing ecosystem evolution, exerting a profound impact on plant diversity and community stability. Understanding post-fire recovery strategies holds significant scientific importance for the ecological succession and restoration of forest ecosystems. This study utilized Partial Least Squares Path Modeling (PLS-PM) to investigate dynamic relationships among plant species diversity, phylogenetic diversity, soil properties, and community stability during various recovery stages (5-year, 15-year, and 23-year) following wildfires on the northeastern margin of the Qinghai-Tibet Plateau. The findings revealed: (1) Over time, species richness significantly decreased (p< 0.05 or p< 0.01), while species diversity and dominance increased, resulting in uniform species distribution. Community stability progressively improved, with increased species compositional similarity. (2) Throughout succession, phylogenetic diversity (PD) significantly decreased (p< 0.01), accompanied by rising Mean Pairwise Distance (MPD) and Mean Nearest Taxon Distance (MNTD). Net Relatedness Index (NRI) shifted from positive to negative, indicating an increasing aggregation and dominance of plants with similar evolutionary traits in burned areas. Early succession witnessed simultaneous environmental filtering and competitive exclusion, shifting predominantly to competitive exclusion in later stages. (3) PLS-PM revealed that in the early recovery stage, soil properties mainly affected community stability, while species diversity metamorphosed into the primary factor in the mid-to-late stages. In summary, this study showed that plant diversity and phylogenetic variation were successful in revealing changes in community structure during the succession process. Soil characteristics functioned as selective barriers for plant communities during succession, and community stability underwent a multi-faceted and dynamic process. The soil-plant dynamic feedback continuously enhanced soil conditions and community vegetation structure thereby augmenting stability. Post-fire vegetation gradually transitioned towards the original native state, demonstrating inherent ecological self-recovery capabilities in the absence of secondary disturbances.

Niche convergence and biogeographic history shape elevational tree community assembly in a subtropical mountain forest

Niche convergence or conservatism have been proposed as essential mechanisms underlying elevational plant community assembly in tropical mountain ecosystems. Subtropical mountains, compared to tropical mountains, are likely to be shaped by a mixing of different geographic affinities of species and remain somehow unclear. Here, we used 31 0.1-ha permanent plots distributed in subtropical forests on the eastern and western aspects of the Gaoligong Mountains, southwest China between 1498 m and 3204 m a.sl. to evaluate how niche-based and biogeographic processes shape tree community assembly along elevational gradients. We analyzed the elevational patterns of taxonomic, phylogenetic and functional diversity, as well as of individual traits, and assessed the relative importance of environmental effects on these diversity measures. We then classified tree species as being either tropical affiliated or temperate affiliated and estimated their contribution to the composition of biogeographic affinities. Species richness decreased with elevation, and species composition showed apparent turnover across the aspects and elevations. Most traits exhibited convergent patterns across the entire elevational gradient. Phylogenetic and functional diversity showed opposing patterns, with phylogenetic diversity increasing and functional diversity decreasing with elevation. Soil nutrients, especially phosphorus and nitrogen, appeared to be the main abiotic variables driving the elevational diversity patterns. Communities at lower elevations were occupied by tropical genera, while highlands contained species of tropical and temperate biogeographic affinities. Moreover, the high phylogenetic diversity at high elevations were likely due to differences in evolutionary history between temperate and tropical species. Our results highlight the importance of niche convergence of tropical species and the legacy of biogeographic history on the composition and structure of subtropical mountain forests. Furthermore, limited soil phosphorus caused traits divergence and the partitioning for different forms of phosphorus may explain the high biodiversity found in phosphorus-limited subtropical forests.

Urbanization reduces diversity, simplifies community and filter bird species based on their functional traits in a tropical city

Understanding how organisms are coping with major changes imposed by urban intensification is a complex task. In fact, our understanding of the impacts of urbanization on biodiversity is scarce in the global south compared to the north. In this study, we evaluated how bird communities are affected by impact of urban intensification in a tropical city. Thus, we assessed whether increased urban intensification 1) jeopardizes bird diversity (taking into account taxonomic-TD, phylogenetic-PD, and functional-FD dimensions), 2) drives changes in bird community composition and enables the detection of indicator species of such impact, and 3) leads to changes in bird functional traits linked to reproduction, resource acquisition, and survival. We found that urban intensification has a direct impact on the bird community, reducing all three types of diversity. Communities in areas of greater urban intensity are represented by fewer species, and these species are PD and FD less distinct. In addition, we detected at least ten species of areas of lower urban intensity that proved to be more sensitive to urban intensification. With regard to bird traits, we found no significant responses from reproductive, habitat use and feeding variables. Body weight and tail length were the only variables with significant results, with higher urbanization intensity areas selecting for species with lower weights and longer tails. Given the global biodiversity loss we are observing, this information can guide urban managers and planners in designing urban landscapes to maintain biodiversity in cities.

Low functional redundancy revealed high vulnerability of the subtropical evergreen broadleaved forests to environmental change

Anthropogenic-induced environmental changes threaten forest ecosystems by reducing their biodiversity and adaptive capacity. Understanding the sensitivity of ecosystem function to loss of diversity is vital in designing conservation strategies and maintaining the resilience of forest ecosystems in a changing world. Here, based on unique combinations of ten functional traits (termed as functional entities; FEs), we quantified the metrics of functional redundancy (FR) and functional vulnerability (FV) in 250 forest plots across five locations in subtropical evergreen broadleaved forests. We then examined the potential impacts of species loss on functional diversity in subtropical forest communities along environmental gradients (climate and soil). Results showed that the subtropical forests displayed a low level of functional redundancy (FR < 2). Over 75 % of the FEs in these subtropical forest communities were composed of only one species, with rare species emerging as pivotal contributors to these vulnerable FEs. The number of FEs and functional redundancy both increased with the rise in species richness, but functional vulnerability decreased with increasing species richness. Climatic factors, especially mean diurnal range, played crucial roles in determining the functions that the forest ecosystem delivers. Under variable temperature conditions, species in each plot were packed into a few FEs, leading to higher functional redundancy and lower functional vulnerability. These results highlighted that rare species contribute significantly to ecosystem functions and the highly diverse subtropical forest communities could show more insurance effects against species loss under stressful environmental conditions.

Unique functional diversity during early Cenozoic mammal radiation of North America

Mammals influence nearly all aspects of energy flow and habitat structure in modern terrestrial ecosystems. However, anthropogenic effects have probably altered mammalian community structure, raising the question of how past perturbations have done so. We used functional diversity (FD) to describe how the structure of North American mammal palaeocommunities changed over the past 66 Ma, an interval spanning the radiation following the K/Pg and several subsequent environmental disruptions including the Palaeocene-Eocene Thermal Maximum (PETM), the expansion of grassland, and the onset of Pleistocene glaciation. For 264 fossil communities, we examined three aspects of ecological function: functional evenness, functional richness and functional divergence. We found that shifts in FD were associated with major ecological and environmental transitions. All three measures of FD increased immediately following the extinction of the non-avian dinosaurs, suggesting that high degrees of ecological disturbance can lead to synchronous responses both locally and continentally. Otherwise, the components of FD were decoupled and responded differently to environmental changes over the last ~56 Myr.

Soil flooding filters evolutionary lineages of tree communities in Amazonian riparian forests

Inundations in Amazonian black-water river floodplain result in the selection of different tree lineages, thus promoting coexistence between species. We investigated whether Amazonian tree communities are phylogenetically structured and distributed along a flooding gradient from irregularly flooded forests along streams embedded within upland (terra-firme) forest to seasonally flooded floodplains of large rivers (igapós). Floristic inventories and hydrological monitoring were performed along the Falsino River, a black-water river in the eastern Amazon within the Amapá National Forest. We constructed a presence-and-absence matrix and generated a phylogeny using the vascular plant database available in GenBank. We calculated the standardized values of the metrics of phylogenetic diversity (ses.PD), average phylogenetic distance (ses.MPD), and average nearest-neighbor distance (ses.MNTD) to test whether the history of relationships between species in the community is influenced by inundation. We used the phylogenetic endemism (PE) metric to verify the existence of taxa with restricted distribution. Linear regressions were used to test whether phylogenetic metrics have a significant relationship with the variables: maximum flood height, maximum water table depth, and maximum flood amplitude. The results show that forests subject to prolonged seasonal flooding have reduced taxon richness, low phylogenetic diversity, and random distribution of lineages within communities. On the other hand, terra-firme riparian forests showed higher rates of taxon richness, diversity, and phylogenetic dispersion, in addition to greater phylogenetic endemism. These results indicate that seasonal and predictable soil flooding filters tree lineages along the hydrographic gradient. Different adaptations to root waterlogging are likely requirements for colonization in these environments and may represent an important factor in the diversification of tree lineages in the Amazon biome.

Woody plant taxonomic, functional, and phylogenetic diversity decrease along elevational gradients in Andean tropical montane forests: Environmental filtering and arrival of temperate taxa

Mountains are paramount for exploring biodiversity patterns due to the mosaic of topographies and climates encompassed over short distances. Biodiversity research has traditionally focused on taxonomic diversity when investigating changes along elevational gradients, but other facets should be considered. For first time, we simultaneously assessed elevational trends in taxonomic, functional, and phylogenetic diversity of woody plants in Andean tropical montane forests and explored their underlying ecological and evolutionary causes. This investigation covered four transects (traversing ca. 2200 m a.s.l.) encompassing 114 plots of 0.1 ha across a broad latitudinal range (ca. 10°). Using Hill numbers to quantify abundance-based diversity among 37,869 individuals we observed a consistent decrease in taxonomic, functional, and phylogenetic diversity as elevation increased, although the decrease was less pronounced for higher Hill orders. The exception was a slight increase in phylogenetic diversity when dominant species were over-weighted. The decrease in taxonomic and functional diversity might be attributed to an environmental filtering process towards highlands, where the increasingly harsher conditions exclude species and functional strategies. Besides, the differences in steepness decrease between Hill orders suggest that rare species disproportionately contribute to functional diversity. For phylogenetic diversity the shifting elevational trend between Hill orders indicates a greater than previously considered influence in central Andean highlands of tropical lowlands originated species with strong niche conservatism relative to distantly related temperate lineages. This could be explained by a decreasing presence and abundance of temperate, extratropical taxa towards the central Andes relative to northern or southern Andes, where they are more prevalent.

Where the not-so-wild things are in cities? The influence of social-ecological factors in urban trees at multiple scales

Green infrastructure plays an essential role in cities due to the ecosystem services it provides. However, these elements are shaped by social and ecological factors that influence their distribution and diversity, affecting ecological functions and human well-being. Here, we analyzed neighborhood tree distribution - trees in pocket parks, squares and along streets - in Lisbon (Portugal) and modelled tree abundance and taxonomic and functional diversity, at the parish and local scales, considering a comprehensive list of social and ecological factors. For the functional analyses, we included functional traits linked to dispersal, resilience to important perturbations in coastal Mediterranean cities, and ecosystem services delivery. Our results show not only that trees are unevenly distributed across the city, but that there is a strong influence of social factors on all biological indices considered. At the parish and local scales, abundance and diversity responded to different factors, with abundance being linked to both social and ecological variables. Although the influence of social factors on urban trees can be expected, by modelling their influence we can quantify how much humans modify urban landscapes at a structural and functional level. These associations can underlie potential biodiversity filters and should be analyzed over time to inform decisions that support long-term ecological resilience, maximize trait functional expression, and increase equity in ecosystem services delivery.

Research needs on the biodiversity-ecosystem functioning relationship in drylands

Research carried out in drylands over the last decade has provided major insights on the biodiversity-ecosystem functioning relationship (BEFr) and about how biodiversity interacts with other important factors, such as climate and soil properties, to determine ecosystem functioning and services. Despite this, there are important gaps in our understanding of the BEFr in drylands that should be addressed by future research. In this perspective we highlight some of these gaps, which include: 1) the need to study the BEFr in bare soils devoid of perennial vascular vegetation and biocrusts, a major feature of dryland ecosystems, 2) evaluating how intra-specific trait variability, a key but understudied facet of functional diversity, modulate the BEFr, 3) addressing the influence of biotic interactions on the BEFr, including plant-animal interactions and those between microorganisms associated to biocrusts, 4) studying how differences in species-area relationships and beta diversity are associated with ecosystem functioning, and 5) considering the role of temporal variability and human activities, both present and past, particularly those linked to land use (e.g., grazing) and urbanization. Tackling these gaps will not only advance our comprehension of the BEFr but will also bolster the effectiveness of management and ecological restoration strategies, crucial for safeguarding dryland ecosystems and the livelihoods of their inhabitants.

Probiotic Insights from the Genomic Exploration of Lacticaseibacillus paracasei Strains Isolated from Fermented Palm Sap

This study focused on L. paracasei strains isolated from fermented palm sap in southern Thailand that exhibit potential probiotic characteristics, including antibiotic susceptibility, resistance to gastrointestinal stresses, and antimicrobial activity against various pathogens. However, a thorough investigation of the whole genome sequences of L. paracasei isolates is required to ensure their safety and probiotic properties for human applications. This study aimed to sequence the genome of L. paracasei isolated from fermented palm sap, to assess its safety profile, and to conduct a comprehensive comparative genomic analysis with other Lacticaseibacillus species. The genome sizes of the seven L. paracasei strains ranged from 3,070,747 bp to 3,131,129 bp, with a GC content between 46.11% and 46.17% supporting their classification as nomadic lactobacilli. In addition, the minimal presence of cloud genes and a significant number of core genes suggest a high degree of relatedness among the strains. Meanwhile, phylogenetic analysis of core genes revealed that the strains possessed distinct genes and were grouped into two distinct clades. Genomic analysis revealed key genes associated with probiotic functions, such as those involved in gastrointestinal, oxidative stress resistance, vitamin synthesis, and biofilm disruption. This study is consistent with previous studies that used whole-genome sequencing and bioinformatics to assess the safety and potential benefits of probiotics in various food fermentation processes. Our findings provide valuable insights into the potential use of seven L. paracasei strains isolated from fermented palm sap as probiotic and postbiotic candidates in functional foods and pharmaceuticals.

Sr/Ca ratios indicate frugivory versus folivory in primates: a case study using handheld XRF in Kibale National Park, Uganda

Researchers often use trace element concentrations, including strontium-calcium ratios (Sr/Ca), to reconstruct paleodiets. While most commonly used as a proxy for meat consumption, a more appropriate application may be to differentiate frugivory from folivory. Sr/Ca ratios in animal tissue reflect the Sr/Ca ratios of the highest calcium components of that animal's diet. Because plants have much higher concentrations of calcium than meat, meat consumption signals are often overwhelmed by the variation in Sr/Ca ratios coming from different plant parts. This study uses faunal and plant data from Kibale National Park, a protected forest in southwestern Uganda home to numerous primate species (for example, common chimpanzees and baboons), to assess the reliability of Sr/Ca ratios to differentiate between primate dietary groups. We find that leaves consistently have higher strontium and calcium concentrations than fruits and that this is mirrored in higher Sr/Ca ratios in folivorous primates compared to frugivorous primates. Plant species differ widely in both their overall Sr/Ca ratios and the differences between their fruit and leaf Sr/Ca ratios, but this variation does not overwhelm the dietary signal separating frugivores and folivores. Furthermore, this research demonstrates that non-destructive and portable X-ray florescence (XRF) methods are an effective means of gathering Sr/Ca data from plant and faunal material, increasing the opportunities to apply such methods to fossil material in the future.

Trait-environment interactions of saproxylic beetles as a guide to biodiversity conservation strategies

Conservation of biodiversity requires in-depth knowledge of trait-environment interactions to understand the influence the environment has on species assemblages. Saproxylic beetles exhibit a wide range of traits and functions in the forest ecosystems. Understanding their responses to surrounding environment thus improves our capacity to identify habitats that should be restored or protected. We investigated potential interactions between ecological traits in saproxylic beetles (feeding guilds and habitat preferences) and environmental variables (deadwood, type and age of surrounding forest). We sampled beetles from 78 plots containing newly created high stumps of Scots pine and Silver birch in boreal forest landscapes in Sweden for three consecutive years. Using a model based approach, our aim was to explore potential interactions between ecological traits and the surrounding environment at close and distant scale (20 m and 500 m radius). We found that broadleaf-preferring beetle species are positively associated with the local broadleaf-originated deadwood and broadleaf-rich forests in the surrounding landscapes. Conifer-preferring species are positively associated with the local amount of coniferous deadwood and young and old forests in the surrounding landscape. Fungivorous and predatory beetles are positively associated with old forests in the surrounding landscapes. Our results indicate that both local amounts of deadwood and types of forests in the landscape are important in shaping saproxylic beetle communities. We particularly highlight the need to increase deadwood amounts of various qualities in the landscape, exempt older forests from production and to increase broadleaf-rich habitats in order to meet different beetle species' habitat requirements. Trait responses among saproxylic beetles provide insights into the significance of broadleaf forest and dead wood as essential attributes in boreal forest restoration, which helps conservation planning and management in forest landscapes.

Functional diversity and metabolic response in benthic communities along an ocean acidification gradient

Altered ocean chemistry caused by ocean acidification (OA) is expected to have negative repercussions at different levels of the ecological hierarchy, starting from the individual and scaling up to the community and ultimately to the ecosystem level. Understanding the effects of OA on benthic organisms is of primary importance given their relevant ecological role in maintaining marine ecosystem functioning. The use of functional traits represents an effective technique to investigate how species adapt to altered environmental conditions and can be used to predict changes in the resilience of communities faced with stresses associated with climate change. Artificial supports were deployed for 1-y along a natural pH gradient in the shallow hydrothermal systems of the Bottaro crater near Panarea (Aeolian Archipelago, southern Tyrrhenian Sea), to explore changes in functional traits and metabolic rates of benthic communities and the repercussions in terms of functional diversity. Changes in community composition due to OA were accompanied by modifications in functional diversity. Altered conditions led to higher oxygen consumption in the acidified site and the selection of species with the functional traits needed to withstand OA. Calcification rate and reproduction were found to be the traits most affected by pH variations. A reduction in a community's functional evenness could potentially reduce its resilience to further environmental or anthropogenic stressors. These findings highlight the ability of the ecosystem to respond to climate change and provide insights into the modifications that can be expected given the predicted future pCO2 scenarios. Understanding the impact of climate change on functional diversity and thus on community functioning and stability is crucial if we are to predict changes in ecosystem vulnerability, especially in a context where OA occurs in combination with other environmental changes and anthropogenic stressors.

Identifying global conservation priorities for terrestrial vertebrates based on multiple dimensions of biodiversity

The Kunming-Montreal Global Biodiversity Framework of the Convention on Biological Diversity calls for an expansion of the current protected areas (PAs) to cover at least 30% of global land and water areas by 2030 (i.e., the 30×30 target). Efficient spatial planning for PA expansion is an urgent need for global conservation practice. A spatial prioritization framework considering multiple dimensions of biodiversity is critical for improving the efficiency of the spatial planning of PAs, yet it remains a challenge. We developed an index for the identification of priority areas based on functionally rare, evolutionarily distinct, and globally endangered species (FREDGE) and applied it to 21,536 terrestrial vertebrates. We determined species distributions, conservation status (global endangerment), molecular phylogenies (evolutionary distinctiveness), and life-history traits (functional rarity). Madagascar, Central America, and the Andes were of high priority for the conservation of multiple dimensions of terrestrial vertebrate biodiversity. However, 68.8% of grid cells in these priority areas had <17% of their area covered by PAs, and these priority areas were under intense anthropogenic and climate change threats. These results highlight the difficulties of conserving multiple dimensions of biodiversity. Our global analyses of the geographical patterns of multiple dimensions of terrestrial vertebrate biodiversity demonstrate the insufficiency of the conservation of different biodiversity dimensions, and our index, based on multiple dimensions of biodiversity, provides a useful tool for guiding future spatial prioritization of PA expansion to achieve the 30×30 target under serious pressures.

Shifting the paradigm: The role of introduced plants in the resiliency of terrestrial ecosystems to climate change

Current ecological communities are in a constant state of flux from climate change and from species introductions. Recent discussion has focused on the positive roles introduced species can play in ecological communities and on the importance of conserving resilient ecosystems, but not how these two ideas intersect. There has been insufficient work to define the attributes needed to support ecosystem resilience to climate change in modern communities. Here, I argue that non-invasive, introduced plant species could play an important role in supporting the resilience of terrestrial ecosystems to climate change. Using examples from multiple taxonomic groups and ecosystems, I discuss how introduced plants can contribute to ecosystem resilience via their roles in plant and insect communities, as well as their associated ecosystem functions. I highlight the current and potential contributions of introduced plants and where there are critical knowledge gaps. Determining when and how introduced plants are contributing to the resilience of ecosystems to climate change will contribute to effective conservation strategies.

Body size mediates the functional potential of soil organisms by diversity and community assembly across soil aggregates

Body size is an important life-history trait that affects organism niche occupancy and ecological interactions. However, it is still unclear to what extent the assembly process of organisms with different body sizes affects soil biogeochemical cycling processes at the aggregate level. Here, we examined the diversity and community assembly of soil microorganisms (bacteria, fungi, and protists) and microfauna (nematodes) with varying body sizes. The microbial functional potential associated with carbon, nitrogen, phosphorus, and sulfur metabolism within three soil aggregate sizes (large macroaggregates, > 2 mm; small macroaggregates, 0.25-2 mm; and microaggregates, < 0.25 mm) were determined by metagenomics. We found that the smallest microbes (bacteria) had higher α-diversity and lower β-diversity and were mostly structured by stochastic processes, while all larger organisms (fungi, protists, and nematodes) had lower α-diversity and were relatively more influenced by deterministic processes. Structural equation modeling indicated that the microbial functional potential associated with carbon, nitrogen, phosphorus, and sulfur metabolism was mainly influenced by the bacterial and protist diversity in microaggregates. In contrast, the microbial functional potential was primarily mediated by the assembly processes of four organism groups, especially the nematode community in macroaggregates. This study reveals the important roles of soil organisms with different body sizes in the functional potential related to nutrient cycling, and provides new insights into the ecological processes structuring the diversity and community assembly of organisms of different body sizes at the soil aggregate level, with implications for soil nutrient cycling dynamics.

Forest disturbance increases functional diversity but decreases phylogenetic diversity of an arboreal tropical ant community

Tropical rainforest trees host a diverse arthropod fauna that can be characterised by their functional diversity (FD) and phylogenetic diversity (PD). Human disturbance degrades tropical forests, often coinciding with species invasion and altered assembly that leads to a decrease in FD and PD. Tree canopies are thought to be particularly vulnerable, but rarely investigated. Here, we studied the effects of forest disturbance on an ecologically important invertebrate group, the ants, in a lowland rainforest in New Guinea. We compared an early successional disturbed plot (secondary forest) to an old-growth plot (primary forest) by exhaustively sampling their ant communities in a total of 852 trees. We expected that for each tree community (1) disturbance would decrease FD and PD in tree-dwelling ants, mediated through species invasion. (2) Disturbance would decrease ant trait variation due to a more homogeneous environment. (3) The main drivers behind these changes would be different contributions of true tree-nesting species and visiting species. We calculated FD and PD based on a species-level phylogeny and 10 ecomorphological traits. Furthermore, we assessed by data exclusion the influence of species, which were not nesting in individual trees (visitors) or only nesting species (nesters), and of non-native species on FD and PD. Primary forests had higher ant species richness and PD than secondary forest. However, we consistently found increased FD in secondary forest. This pattern was robust even if we decoupled functional and phylogenetic signals, or if non-native ant species were excluded from the data. Visitors did not contribute strongly to FD, but they increased PD and their community weighted trait means often varied from nesters. Moreover, all community-weighted trait means changed after forest disturbance. Our finding of contradictory FD and PD patterns highlights the importance of integrative measures of diversity. Our results indicate that the tree community trait diversity is not negatively affected, but possibly even enhanced by disturbance. Therefore, the functional diversity of arboreal ants is relatively robust when compared between old-growth and young trees. However, further study with higher plot-replication is necessary to solidify and generalise our findings.

Stochastic processes shape the functional and phylogenetic structure of bird assemblages at the mine area in southwest China

Understanding the mechanisms of community assembly is a key question in ecology. Metal pollution may result in significant changes in bird community structure and diversity, with implications for ecosystem processes and function. However, the relative importance of these processes in shaping the bird community at the polluted area is still not clear. Here, we explored bird species richness, functional, and phylogenetic diversity, and the assembly processes of community at the mine region of southwest China. Our results showed that the 3 dimensions of diversity at the mine area were lower than that at the reference sites. In the community assembly, the result was 0 < NRI/ NFRI < 1.96, which indicated deterministic processes (environmental filtering) might drive community clustering. The results of the neutral community model, and normalized stochasticity ratio, showed the dominant role of stochastic processes in shaping the bird community assembly. We further quantified the community-level habitat niche breadth (Bcom), and we found that there was no difference in Bcom-value between the mine area and reference sites. This indicates that the bird communities at the mine area and 3 reference sites were not subjected to extreme environmental selection (same or different resource allocation) to form a highly specialized niche. These findings provide insights into the distribution patterns and dominant ecological processes of bird communities under metal exposure, and extend the knowledge in community assembly mechanisms of bird communities living in the mine area.

Global multifaceted biodiversity patterns, centers, and conservation needs in angiosperms

The Convention on Biological Diversity seeks to conserve at least 30% of global land and water areas by 2030, which is a challenge but also an opportunity to better preserve biodiversity, including flowering plants (angiosperms). Herein, we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 species. Using this database, we constructed biodiversity-environment models to predict global patterns of taxonomic, phylogenetic, and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity facets. We further evaluated the current protection status of the biodiversity centers of these diversity facets. Our results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation priorities. Idiosyncratic centers of functional diversity, particularly of herbaceous species, were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic facets. Our global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms (woody vs. herbaceous), thus providing directions for guiding the future conservation of global plant diversity.

Decoupled response of microbial taxa and functions to nutrients: The role of stoichiometry in plantations

The resource quantity and elemental stoichiometry play pivotal roles in shaping belowground biodiversity. However, a significant knowledge gap remains regarding the influence of different plant communities established through monoculture plantations on soil fungi and bacteria's taxonomic and functional dynamics. This study aimed to elucidate the mechanisms underlying the regulation and adaptation of microbial communities at the taxonomic and functional levels in response to communities formed over 34 years through monoculture plantations of coniferous species (Japanese larch, Armand pine, and Chinese pine), deciduous forest species (Katsura), and natural shrubland species (Asian hazel and Liaotung oak) in the temperate climate. The taxonomic and functional classifications of fungi and bacteria were examined for the mineral topsoil (0-10 cm) using MiSeq-sequencing and annotation tools of microorganisms (FAPROTAX and Funguild). Soil bacterial (6.52 ± 0.15) and fungal (4.46 ± 0.12) OTUs' diversity and richness (5.83*103±100 and 1.12*103±46.4, respectively) were higher in the Katsura plantation compared to Armand pine and Chinese pine. This difference was attributed to low soil DOC/OP (24) and DON/OP (11) ratios in the Katsura, indicating that phosphorus availability increased microbial community diversity. The Chinese pine plantation exhibited low functional diversity (3.34 ± 0.04) and richness (45.2 ± 0.41) in bacterial and fungal communities (diversity 3.16 ± 0.15 and richness 56.8 ± 3.13), which could be attributed to the high C/N ratio (25) of litter. These findings suggested that ecological stoichiometry, such as of enzyme, litter C/N, soil DOC/DOP, and DON/DOP ratios, was a sign of the decoupling of soil microorganisms at the genetic and functional levels to land restoration by plantations. It was found that the stoichiometric ratios of plant biomass served as indicators of microbial functions, whereas the stoichiometric ratios of available nutrients in soil regulated microbial genetic diversity. Therefore, nutrient stoichiometry could serve as a strong predictor of microbial diversity and composition during forest restoration.

Letting the plants speak: Law, landscape and conservation

The Botany Wetlands are the contemporary remnant of a formerly extensive coastal freshwater wetland in the inner-urban suburbs of Sydney (Australia). This site supports a range of ecosystem services, including human physical and mental health benefits, filtration of stormwater runoff from a highly urban and industrial catchment, and accommodation space for floodwater. The wetlands also provide habitat to migratory water birds and act as a connective habitat corridor and refuge for native flora and fauna including endangered ecological communities recognised in state and national legislation. Current management strategies and 'on the ground' practices are informed by a hierarchy of laws and management plans that act to create and reinforce a specific narrative in the material landscape. Here we consider the ecological history of the wetlands, derived from paleoecological data, in the context of this complex network of governance entanglements. We argue that the system bears little resemblance to its long-term character and has been made and continually re-made by a portmanteau of inflexible regulatory structures. We suggest that maintaining ecosystem services in such a complex, hybridized sociolegal-biophysical system requires a critical view of both the power relations and physical processes that shape it.

Nature-based solutions for coastal protection in sheltered and exposed coastal waters: integrated monitoring program for baseline ecological structure and functioning assessment

Nature-based solutions, such as shellfish reefs, can support natural coastal defence and be a potential solution for climate-resilient shorelines in the future. In the Belgian Part of the North Sea, the "Coastbusters" projects aim to develop nature-based coastal protection by favouring subtidal mussel bed establishment on the seafloor through typical longline aquaculture techniques. Mussel beds are dependent on environmental conditions, and both influence the physical and biogeochemical features in a soft-sediment environment. Therefore, a comprehensive ecological monitoring program is essential to assess the success of future mussel bed development and its influence on the surrounding ecosystem. For establishing a monitoring baseline of the two experimental areas, a combination of conventional benthic assessment methods (grab sampling and granulometry) and non-invasive techniques (sediment profile imaging and transect diving video surveys) were utilised. Although mussel reefs did not yet develop by the time of this study, clear differences in ecological and sedimentological characteristics were found between two experimental areas (sheltered and exposed), subjected to slightly different hydrodynamic conditions. The one sheltered by coastal sandbanks was dominated by fine-muddy sand, higher species richness, biomass, and higher biological activity (burrows, fauna, and biological beds) as observed by all methods in one or another way. Moreover, functional diversity indices revealed a higher partitioning of the total available resources, suggesting more complex ecological processes in the sheltered area. Conversely, the area more exposed to the open sea was dominated by more sandy sediments, and fewer organisms were found. The combination of those different monitoring tools provides an integrated, complementary view, from different perspectives, on the biological, physical and functional characteristics of the study areas.

Woody species composition, diversity, and ecosystem services of yards along an urban socioeconomic gradient

Woody plants offer a wide range of valuable ecosystem services, but their distribution across socioeconomic gradients in urban landscapes remains poorly understood. Thus, we explored the effect of socioeconomic and legacy factors on plant species richness and phylogenetic diversity, and the motivations for growing and keeping certain species. We sampled a total of 300 households across a socioeconomic gradient in the city of Harare, Zimbabwe, in high-, medium- and low-density areas, representing low to high wealth strata. Trees were mostly grown for ornamental purpose in the rich (low-density) suburbs and utilitarian purposes in the poorer medium to high-density areas. However, trees were also grown with similar proportion for shade across the socioeconomic gradient. Proportion of medicinal and fruit trees increased with household density, while wind break trees were more common in low-density suburbs. Exotic species exhibited greater species richness compared with indigenous species, with both combined and separate assessments of indigenous and exotic species richness revealing a significant positive association with socioeconomic and legacy factors. The composition of species displayed considerable variation along the socioeconomic gradient. Notably, in low-density environments, exotic species maintained elevated phylogenetic diversity in comparison to indigenous species. This distinction was particularly pronounced when analysed independently, revealing a significant positive correlation between exotic species richness and both property value and education level. Our study shows that residents filter specific plant species based on their socioeconomic status and that, relative to low-income households, the rich homeowners have unintentionally incorporated enough exotic species to produce novel phylogenetic diversity of woody plants in their yards. Thus, we confirm the existence of a socioeconomic gradient in terms of species richness, composition, and phylogenetic diversity. However, the imbalance in species richness and phylogenetic diversity across the socioeconomic gradient can be reduced by increased tree planting in open areas, including along streets in medium to high-density areas to improve ecosystem services.

Identifying Roadkill Hotspots for Mammals in the Brazilian Atlantic Forest using a Functional Group Approach

A critical step to design wildlife mitigating measures is the identification of roadkill hotspots. However, the effectiveness of mitigations based on roadkill hotspots depends on whether spatial aggregations are recurrent over time, spatially restricted, and most importantly, shared by species with diverse ecological and functional characteristics. We used a functional group approach to map roadkill hotspots for mammalian species along the BR-101/North RJ, a major road crossing important remnants of the Brazilian Atlantic Forest. We tested if functional groups present distinct hotspot patterns, and if they converge into the same road sectors, in that case, favoring optimal mitigating actions. Roadkill rates were monitored and recorded between October/2014 and September/2018 and species were classified into six functional groups based on their home range, body size, locomotion mode, diet, and forest-dependency. Hotspots along the roads were mapped for comparison of spatial patterns between functional groups. Results demonstrated that the roadkill index varied idiosyncratically for each functional group throughout the months and that no group presented seasonality. Seven hotspots were shared by two or more functional groups, highlighting the importance of these road stretches to regional mammal fauna. Two of the stretches are associated with aquatic areas extending from one side of the road to the other, and the remaining are connected to patches of native vegetation on both sides. This work brings a promising approach, yet hardly used in ecological studies on roads to analyze roadkill dynamics, assigning more importance to ecological instead of taxonomical characteristics, normally used to identify spatiotemporal patterns.

Effects of Aquatic Plant Coverage on Diversity and Resource Use Efficiency of Phytoplankton in Urban Wetlands: A Case Study in Jinan, China

With the acceleration of urbanization, biodiversity and ecosystem functions of urban wetlands are facing serious challenges. The loss of aquatic plants in urban wetlands is becoming more frequent and intense due to human activities; nevertheless, the effects of aquatic plants on wetland ecosystems have received less attention. Therefore, we conducted field investigations across 10 urban wetlands in Jinan, Shandong Province, as a case in North China to examine the relationships between aquatic plant coverage and phytoplankton diversity, as well as resource use efficiency (RUE) in urban wetlands. Multivariate regression and partial least squares structural equation modeling (PLS-SEM) were used to analyze the water quality, phytoplankton diversity, and RUE. The results demonstrate that the increase in aquatic plant coverage significantly reduced the concentration of total nitrogen and suspended solids' concentrations and significantly increased the phytoplankton diversity (e.g., species richness and functional diversity). The aquatic plant coverage significantly affected the composition of phytoplankton functional groups; for example, functional groups that had adapted to still-water and low-light conditions became dominant. Furthermore, the increase in phytoplankton diversity improved phytoplankton RUE, highlighting the importance of aquatic plants in maintaining wetland ecosystem functions. This study may provide a scientific basis for the management strategy of aquatic plants in urban wetlands, emphasizing the key role of appropriate aquatic plant cover in maintaining the ecological stability and ecosystem service functions of wetlands.

Niche types and community assembly

Studies of niche differentiation and biodiversity often focus on a few niche dimensions due to the methodological challenge of describing hyperdimensional niche space. However, this may limit our understanding of community assembly processes. We used the full spectrum of realized niche types to study arbuscular mycorrhizal fungal communities: distinguishing abiotic and biotic, and condition and resource, axes. Estimates of differentiation in relation to different niche types were only moderately correlated. However, coexisting taxon niches were consistently less differentiated than expected, based on a regional null model, indicating the importance of habitat filtering at that scale. Nonetheless, resource niches were relatively more differentiated than condition niches, which is consistent with the effect of a resource niche-based coexistence mechanism. Considering niche types, and in particular distinguishing resource and condition niches, provides a more complete understanding of community assembly, compared with studying individual niche axes or the full niche.

When Do Traits Tell More Than Species about a Metacommunity? A Synthesis across Ecosystems and Scales

AbstractLinking species traits with the variation in species assemblages across habitats has often proved useful for developing a more mechanistic understanding of species distributions in metacommunities. However, summarizing the rich tapestry of a species in all of its nuance with a few key ecological traits can also lead to an abstraction that provides less predictability than when using taxonomy alone. As a further complication, taxonomic and functional diversities can be inequitably compared, either by integrating taxonomic-level information into the calculation of how functional aspects of communities vary or by detecting spurious trait-environment relationships. To remedy this, we here synthesize analyses of 80 datasets on different taxa, ecosystems, and spatial scales that include information on abundance or presence/absence of species across sites with variable environmental conditions and the species' traits. By developing analyses that treat functional and taxonomic diversity equitably, we ask when functional diversity helps to explain metacommunity structure. We found that patterns of functional diversity explained metacommunity structure and response to environmental variation in only 25% of the datasets using a multitrait approach but up to 59% using a single-trait approach. Nevertheless, an average of only 19% (interquartile range = 0%-29%) of the traits showed a significant signal across environmental gradients. Species-level traits, as typically collected and analyzed through functional diversity patterns, often do not bring predictive advantages over what the taxonomic information already holds. While our assessment of a limited advantage of using traits to explain variation in species assemblages was largely true across ecosystems, traits played a more useful role in explaining variation when many traits were used and when trait constructs were more related to species' status, life history, and mobility. We propose future research directions to make trait-based approaches and data more helpful for inference in metacommunity ecology.

Environmental heterogeneity of cold seep by biological trait analysis of marine nematodes at Site F cold seep in South China Sea

Cold seeps provide high environmental heterogeneity for marine benthos. Site F is one of the active cold seeps in the South China Sea. In this study, free-living marine nematode communities were investigated at Site F and the adjacent deep-sea area. A total of 67 genera and 32 families were identified. The mean density at cold seep sites ranged from 13.6 to 181.8 ind./10 cm2, and that at the adjacent deep-sea sites ranged from 36.9 to 301.4 ind./10 cm2. At cold seep sites, the most dominant nematode genera were Desmoscolex, Pierrickia, Sabatieria, Halalaimus, and Dorylaimopsis while at deep-sea sites, the most dominant genera were Retrotheristus, Thalassomonhystera, Desmoscolex, Cobbia, and Halalaimus. Deposit feeders of nematodes were dominant at all sites. Results of biological trait analysis showed that there was high environmental heterogeneity for nematodes at Site F. Water depth, sediment organic matter content, and sand proportion had important influences on nematode communities.