Functional Diversity Measures Research Articles

Functional diversity of the macrofauna communities in arid mangroves of the Persian Gulf and Gulf of Oman

Understanding the patterns and drivers of biodiversity in intertidal zones is essential for developing effective conservation strategies. The taxonomic and functional diversity of macrofaunal communities was studied in the arid mangrove system of the Persian Gulf and Gulf of Oman. The study further aimed to investigate whether the main functional traits differ between habitats. All macrofauna samples and environmental variables were taken from two habitats including vegetated habitat and adjoining mudflats. A total of 85 taxa was found, of which 19 taxa were exclusive to vegetated habitats and 20 to mudflats. Mollusca were the most species-rich group in both habitats, followed by Arthropoda and Annelida. When comparing diversity indices among regions and habitats the Shannon-Wiener diversity index was significantly higher in vegetated habitats compared to mudflats. However, these trends were less consistent for the functional diversity measures being very much region-dependent. The results showed that functional trait structure was more uniform than the taxonomic structure across regions and habitats. The trait modalities biodiffuser, surface deposit-feeder, burrower, free-living, planktotrophic, 2–5 years, and 10–50 mm were common at both habitats. However, the modalities detritivore and grazer/scarper, and direct larval development were significantly higher in vegetated habitats than in mudflats. The vegetated habitats exhibited the more functionally redundant communities than mudflats, possibly due to higher taxonomic diversity observed in this habitat or the presence of the species with similar functions in the ecosystem. The combined investigation of species and functional diversity of mangrove macrofauna communities conducted in this research is essential for effective management and conservation efforts aimed at protecting mangrove ecosystems and to preserve the goods and services they provide.

Limited complementarity of functional and taxonomic diversity in Chilean benthic marine invertebrates

AbstractAimPatterns of benthic biodiversity at the macroecological scale remain poorly characterised throughout the Chilean latitudinal gradient, in part due to the lack of integrated databases, uneven sampling effort, and the use of species richness alone to quantify biodiversity. Different diversity measures, encompassing taxonomic and functional components, may give us extra information on biodiversity relevant to conservation planning and management. Thus, evaluating the spatial complementarity of these measures is essential.LocationCoast and continental shelf of Chile.MethodsThe latitudinal gradient of Chile was divided into five ecoregions according to the Marine Ecosystems of the World classification. Using a 55 × 55 km equal area grid, we estimated the incidence coverage‐based estimator (ICE), taxonomic distinctness (Δ+) and three measures of functional diversity: functional richness (FRic), functional evenness (FEve) and functional divergence (FDiv). For each measure, we described spatial patterns, identified hotspots, evaluated hotspot congruence and evaluated complementarity between measures.ResultsDiversity patterns varied between ecoregions and over the latitudinal gradient. ICE and Δ+ peaked in the Chiloense and Channels and Fjords ecoregions. Δ+ and FRic present a similar pattern at mid‐latitudes. FEve showed a contrary pattern, principally with FRic. Areas with high numbers of hotspots differed spatially according to each metric, and three latitudinal bands were observed. ICE, Δ+ and FRic were positively correlated, but the hotspot overlap at the grid cell level was more limited.Main ConclusionsThe complementarity between taxonomic and functional diversity measures is limited when we observe the overlap between grid cells representing hotspots. However, some regions are consistently identified as highly diverse, with the Magellanic Province (Chiloense and Channels and Fjords ecoregions) being the most important for the richness, taxonomic and functional diversity of benthos. Confirmation of the importance of this region can help prioritise conservation efforts.

Effects of grazing on the relationship between plant functional diversity and soil carbon sequestration are regulated by livestock species

Abstract Grazing exerts a profound influence on both the plant diversity and productivity of grasslands, while simultaneously exerting a significant impact on regulating grassland soil carbon sequestration. Moreover, besides altering the taxonomic diversity of plant communities, grazing can also affect their diversity of functional traits. However, we still poorly understand how grazing modifies the relationship between plant functional diversity and soil carbon sequestration in grassland ecosystems. Here we conducted a grazing manipulation experiment to investigate the effects of different grazing regimes (no grazing; sheep grazing; cattle grazing) on the relationships between plant functional diversity and soil carbon sequestration in meadow and desert steppe. Our findings showed that different livestock species changed the relationships between plant functional diversity and soil organic carbon (SOC) in the meadow steppe. Sheep grazing decoupled the originally positive relationship between functional diversity and SOC, whereas cattle grazing changed the relationship from positive to negative. In desert steppe both sheep and cattle grazing strengthened the positive relationship between functional diversity and SOC. Our study illuminates the considerable impact of livestock species on the intricate mechanisms of soil carbon sequestration, primarily mediated through the modulation of various measures of functional trait diversity. In ungrazed meadows and grazed deserts, maintaining high plant functional diversity is conducive to soil carbon sequestration, whereas in grazed meadows and ungrazed deserts, this relationship may disappear or even reverse. By measuring the traits and controlling the grazing activities, we can accurately predict the carbon sequestration potential in grassland ecosystems.

Multimodal measures of spontaneous brain activity reveal both common and divergent patterns of cortical functional organization

Large-scale functional networks have been characterized in both rodent and human brains, typically by analyzing fMRI-BOLD signals. However, the relationship between fMRI-BOLD and underlying neural activity is complex and incompletely understood, which poses challenges to interpreting network organization obtained using this technique. Additionally, most work has assumed a disjoint functional network organization (i.e., brain regions belong to one and only one network). Here, we employ wide-field Ca2+ imaging simultaneously with fMRI-BOLD in mice expressing GCaMP6f in excitatory neurons. We determine cortical networks discovered by each modality using a mixed-membership algorithm to test the hypothesis that functional networks exhibit overlapping organization. We find that there is considerable network overlap (both modalities) in addition to disjoint organization. Our results show that multiple BOLD networks are detected via Ca2+ signals, and networks determined by low-frequency Ca2+ signals are only modestly more similar to BOLD networks. In addition, the principal gradient of functional connectivity is nearly identical for BOLD and Ca2+ signals. Despite similarities, important differences are also detected across modalities, such as in measures of functional connectivity strength and diversity. In conclusion, Ca2+ imaging uncovers overlapping functional cortical organization in the mouse that reflects several, but not all, properties observed with fMRI-BOLD signals.

The influence of time-of-day on estimates of taxonomic versus functional diversity in avian communities

ABSTRACT Avian communities composed of a total of 79 species were sampled repeatedly at different times of day throughout the breeding season in Norfolk, Virginia, USA. Estimates of taxonomic diversity (species richness, Shannon index and probability of interspecific encounter) were highest in the morning, whereas estimates of functional diversity (functional richness, evenness, Rao’s entropy and mean distinctiveness) did not vary significantly throughout the day. These results suggest that estimates of taxonomic diversity in avian communities are biased by time-of-day, but measures of functional diversity may be more robust to such bias.

Facets of functional diversity support niche‐based explanations for Australian biodiversity gradients

AbstractAimThere is widespread support that species richness increases with the available energy of an ecosystem, but the mechanisms underlying this driver of biodiversity patterns remain elusive. We evaluated gradients of functional diversity to test whether the higher species richness of productive, structurally diverse environments is due to a greater range of niches being supported by the abiotic conditions present (environmental filtering), greater availability of biotic resource and habitat niches (more niches) or increasing functional similarity of species (niche packing).LocationAustralia.TaxonBirds and mammals.MethodsWe used structural equation modelling to evaluate the relative contributions of climatic harshness (actual evapotranspiration, AET) and the availability of resource (gross primary productivity, GPP) and habitat (tree height) niches on taxonomic richness and functional richness, dispersion and evenness. We performed parallel analyses within 15 bioclimatic zones and continentally to evaluate the scaling of biodiversity gradients and the shifting balance between niche‐based mechanisms along environmental gradients.ResultsAll continental diversity gradients were primarily associated with energy variables, but while species richness of both taxa and all functional diversity measures of bird assemblages increased with AET, mammal functional diversity was more strongly associated with GPP gradients. Results were more variable at the regional scale, but species richness gradients along tree height (birds and mammals) and GPP (mammals) within bioclimatic zones tended not to be paralleled by increases in functional richness or dispersion.Main ConclusionsThe niche‐based explanations of biodiversity gradients varied in importance with scale, position on environmental gradients and taxonomic group. At the continental extent, bird biodiversity gradients were structured by environmental filtering by climatic harshness, while mammal biodiversity was related to the increasing availability of resource niches with increasing productivity. Niche packing was more prominent at the regional scale, especially in bioclimatic zones where productivity and vegetation height were less limiting, and in mammal assemblages, suggesting that biodiversity patterns scale differently for birds and mammals.

Can immature stages be ignored in studies of forest leaf litter arthropod diversity? A test using Oxford Nanopore DNA barcoding

Abstract Forest soil and leaf litter support diverse arthropod mesofauna for which diversity dynamics is challenging to study due to the high number of species and specimens, small body size and limited taxonomic knowledge. Immature stages (larvae) are even harder to identify than adults, as their morphology is largely unknown. Therefore, larvae are often ignored, even though they may form a substantial proportion of specimens collected, are less mobile than adults and their exclusion may provide an incomplete diversity profile. Here, we use Oxford Nanopore DNA barcoding to investigate whether the inclusion of larvae provides a more complete taxonomic, phylogenetic and functional diversity profiles in leaf litter beetles (Coleoptera) from a subtropical forest in Taiwan. Our results indicate that larvae represent up to 38% of beetle specimens per sample, but most of them belong to 2–3 common species. Larvae of most beetle species are rarely collected repeatedly or in multiple specimens, possibly due to special habitat requirements or high seasonality. Taxonomic, phylogenetic and incidence‐based functional diversity measures were not affected by the exclusion of larvae in the Staphylinidae dataset but were strongly biased in all‐beetle dataset, especially when only common or abundant species were considered. Taxonomic beta diversity was not affected by the omission of larvae. Our results indicate that immature stages may be omitted in ecological studies of arthropods in case both adults and larvae co‐occur in the same habitat, and the sites are sampled repeatedly. Caution is needed (1) in groups in which larvae and adults do not inhabit the same environment or strongly differ in biology, (2) when rare species are omitted or (3) when functional diversity is calculated from abundance data.

Using functional traits to predict pollination services: A review

Pollination is a fundamental ecosystem service. Predictive and mechanistic models linking pollinator community structure to pollination services increasingly incorporate information on unique functional differences among species, so called effects traits. There is little consensus as to which traits are most important in supporting pollination services at either an individual or community level. Here, we synthesise the state of current knowledge regarding the role and efficacy of traits for predicting pollination, as well as the use of different methods for describing the trait structure of pollinator assemblages. We find a wide range of traits are currently used to predict pollination services, including morphological, behavioural and phenological characteristics. However, we show that the evidence demonstrating their importance is often limited or mixed. There is a trade-off in how traits are used between those that are easier to measure, available for many species but have only limited evidence for their role in pollination, vs. those that are harder to measure but with a more robust link with pollination service delivery. We highlight how community weighted means and measures of functional diversity offer important, albeit different insights into pollination service delivery. We discuss how their relative importance is likely to depend on the goals of the study. To maximise fully the utilisation of traits to predict pollination services, future research should be directed towards the widespread and consistent validation of the links among different traits and the pollination service across crop and semi-natural plant communities. Ideally this also needs to address geographical and taxonomic biases in trait collection.

Urbanisation generates multiple trait syndromes for terrestrial animal taxa worldwide

Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats, species, and functional groups. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities. Using a dataset encompassing six terrestrial faunal taxa (amphibians, bats, bees, birds, carabid beetles and reptiles) across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy showing the strongest response. Our findings suggest that urbanisation results in four trait syndromes (mobile generalists, site specialists, central place foragers, and mobile specialists), with resources associated with reproduction and diet likely driving patterns in traits associated with mobility and body size. Functional diversity measures showed varied responses, leading to shifts in trait space likely driven by critical resource distribution and abundance, and taxon-specific trait syndromes. Maximising opportunities to support taxa with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation and helps ensure that urban environments have the capacity to respond to future challenges. These actions are critical to reframe the role of cities in global biodiversity loss.

Ecomorphology and functional diversity of generalist and specialist bird assemblages in Amazonian white-sand ecosystem habitat patches

ABSTRACT Birds that inhabit white-sand ecosystems (WSE) in the Amazon are adapted to habitats distributed as isolated patches. These environments occur in sandy soils that are extremely poor in nutrients, have low floristic diversity and support bird assemblages restricted to WSE. We investigated whether bird species specialized in WSE have morphological or ecological traits that distinguish them from generalist birds that share the same habitat but are not restricted to WSE. We collected morphological and ecological data from 22 specialist and 102 generalist bird species from WSE and described their ecomorphological diversity using multivariate analyses and measures of functional diversity. Understory insectivorous species that move alone or in pairs, were the group with the most species among specialist birds from WSE. In contrast, canopy frugivorous species that form mono- or heterospecific groups were more frequent among generalist species. Specialist and generalist birds overlapped extensively in ecomorphological space, with specialists occupying a narrower space compared to generalists. Functional diversity, however, was not different between specialist and generalist species when controlling for the number of species within the communities. Further studies comparing the ecomorphological diversity of bird assemblages of other environments in the Amazon may highlight the ecological pressures leading to the functional diversity of specialist species in WSE observed in this study.

Multitrophic biodiversity enhances ecosystem functions, services and ecological intensification in agriculture

Abstract One central challenge for humanity is to mitigate and adapt to an ongoing climate and biodiversity crisis while providing resources to a growing human population. Ecological intensification (EI) aims to maximize crop productivity while minimizing impacts on the environment, especially by using biodiversity to improve ecosystem functions and services. Many EI measures are based on trophic interactions between organisms (e.g. pollination, biocontrol). Here, we investigate how research on multitrophic effects of biodiversity on ecosystem functioning could advance the application of EI measures in agriculture and forestry. We review previous studies and use qualitative analyses of the literature to test how important variables such as land-use parameters or habitat complexity affect multitrophic diversity, ecosystem functions and multitrophic biodiversity–ecosystem functioning relationships. We found that positive effects of biodiversity on ecosystem functions are prevalent in production systems, largely across ecosystem function dimensions, trophic levels, study methodologies and different ecosystem functions, however, with certain context dependencies. We also found strong impacts of land use and management on multitrophic biodiversity and ecosystem functions. We detected knowledge gaps in terms of data from underrepresented geographical areas, production systems, organism groups and functional diversity measurements. Additionally, we identified several aspects that require more attention in the future, such as trade-offs between multiple functions, temporal dynamics, effects of climate change, the spatial scale of the measures and their implementation. This information will be vital to ensure that agricultural and forest landscapes produce resources for humanity sustainably within the environmental limits of the planet.

Agricultural conservation may not help Midwestern US freshwater biodiversity in a changing climate

Global climate change and agricultural disturbance often drive freshwater biodiversity changes at the regional level, particularly in the Midwestern US. Agricultural conservation practices have been implemented to reduce sediment and nutrient loading (e.g., crop rotation, cover crops, reduced tillage, and modified fertilizer application) for long-term economic sustainability and environmental resilience. However, the effectiveness of these efforts on freshwater biodiversity is not conclusive. In this study, we used the Kaskaskia River Watershed, Illinois as an example to evaluate how agricultural conservation practices affects both taxonomic and functional diversity under climate changes. The measures of trait-based functional diversity provide mechanistic explanations of biological changes. In specific, we model and predict 1) species richness (SR), 2) functional dispersion (FDis), and 3) functional evenness (FEve). FDis and FEve were based on ecology (life history, habitat preference, and trophic level) and physiology (thermal preference, swimming preference, etc.). The best random-forest regression models showed that flow, temperature, nitrate, and the watershed area were among the top predictors of the three biodiversity measures. We then used the models to predict the changes of SR and FDis under RCP8.5 climate change scenarios. SR and FDis were predicted to decrease in most sites, up to 20 % and 4 % by 2099, respectively. When agricultural conservation practices were considered together with climate changes, the decreasing trends of SR and FDis remained, suggesting climate change outweighed potential agriculture conservation efforts. Thus, climate-change effects on temperature and flow regimes need to be incorporated into the design of agricultural practices for freshwater biodiversity conservation.

Zooplankton functional traits in a tropical estuarine system: Are lower and upper estuaries functionally different?

Functional diversity measures help to understand the underlying mechanisms explaining the relationship between organisms and environment. This work examined the mesozooplankton community of an estuary under the hypothesis that the upper (< 25 psu) and lower (> 25 psu) zones are functionally different in terms of feeding strategies, trophic groups, camouflage, buoyancy, and defense against predators, due to the salinity gradient. We used the ‘community-weighted mean trait values’ (CWM) and a fuzzy correspondence analysis (FCA) in combination with three functional indices (FRic: functional richness, FEve: functional evenness, FDiv: functional divergence) to test our hypothesis. Zooplankton samples were taken in the tropical Sontecomapan estuary, southern Gulf of Mexico, in June 2018 and October 2019. A total of 21 zooplankton groups were recognized, all of them present in the lower estuary. Results showed significant differences (p< 0.05) in the FRic and FDiv values between the two zones, as well in the CWM metric. Results of the FCA showed that the lower estuary was characterized by herbivorous filter feeders that use watery bodies, flattened body forms, mucus houses, or ‘wings’ for buoyancy; highly transparent bodies (associated with gelatinous body structure) for camouflage and predators’ avoidance and, shells or carapaces as antipredator tactics. The upper estuary was characterized by omnivorous cruising predators that use their appendages or swim bladders for buoyancy, with ‘medium’ and ‘low’ levels of transparency, associated with chitinous and skin-protected body structures, which provide alternative ways for camouflage and spines or fast swimming behavior to protect from predators. These findings evidenced that the upper and lower zones of an estuary exhibit differences in the function of the zooplankton community and shed new light on the comprehension of estuaries’ ecological function.

Variations in Avian Species and Functional Diversity in Different Habitat Types in a Vulnerable Savannah Ecosystem in Ghana

Most research on avian functional diversity in the tropics is focused on forest and agroecosystems, leaving a gap in knowledge about the effects of habitat types on functional diversity in savannah landscapes. Savanna ecosystems are fragile and are under threat of anthropogenic destruction, particularly in developing Sub-Saharan Africa and could be eliminated in the face of the ever-increasing human population exacerbated by the changing climate. This study investigated the influence of the three major habitat types (grassland, riparian forest, woodland) on bird species and functional diversity in the Mole National Park (MNP) in Ghana. We used the line transect method to survey birds along 39 transects, each 1 km in length, and collected data on environmental variables along the same transects. Data from these surveys was used to estimate species and functional diversity indicators. We found significant variations in species and functional diversity measures between the three habitat types in the MNP. These variations were significantly influenced by species abundance and environmental covariates. Diversity measures were particularly higher in the riparian forest habitats compared to the woodland and grassland, with the latter being the least diverse habitat both functionally and species wise. The results of this study suggest that the avifauna assemblages in MNP are largely influenced by the riparian forest and are important for ecosystem function and stability. We recommend management efforts to intensify the protection of such vital habitats of the Mole National Park from illegal human activities, especially the rising removal and export of rosewoods (Dalbergia nigra) around the park. Further research on the avian community composition and structure in the MNP is recommended.

Unveiling the drivers of nematode community structure and function across rice agroecosystems

Rice agroecosystems has drawn global attention due to its unique transition of flooding to wetland to a terrestrial ecosystem with high biodiversity throughout its growing period. While biodiversity of the aboveground organisms in the rice ecosystem is well studied, understanding the diversity and functions of soil biota, particularly the nematofauna, are often neglected. In the present study, variations in soil nematode community composition in response to edaphic and climatic variables were assessed (n = 501 samples) across three agro-ecological zones of Jharkhand, India. Functional diversity measures were used to estimate the biological soil health of different rice growing areas across the agroecological zones. Relative contribution of edaphic, climatic and spatial structure in shaping nematode community composition was measured using variation partitioning. Among the identified nematode genera (n = 58), Meloidogyne spp. was the most abundant and dominant taxon. Taxonomic diversity measures varied significantly across agro-ecological zones, with highest diversity reported in the central and north-eastern plateau, followed by the south-eastern plateau and western plateau. Average annual temperature, annual precipitation, available nitrogen and organic carbon had significant relationships with taxonomic diversity measures. The spatial variation map of the nematode community composition depicted spatial heterogeneity across agro-ecological zones. Climatic predictors also strongly influenced both the community composition and richness of nematodes, while edaphic factors showed a strong influence on beta diversity, but not on variation partitioning. A moderate level of spatial structure pattern suggested limited dispersal of nematodes. Functional diversity measures based on nematode community composition depicted better soil biological health in the central and north-eastern plateau than rest two zones. This study demonstrates how climatic predictors have a greater influence on nematode community composition than edaphic parameters, presumably as a result of intensively managed rice agroecosystems.

Examining the relative influence of dispersal and competition on co-occurrence and functional trait patterns in response to disturbance

Disturbance gradients are particularly useful for understanding the relative influences of competition and dispersal. Shortly after disturbance, plant composition should be influenced more strongly by dispersal than competition; over time, this should reverse, with competition becoming more important. As such, we predicted that plant functional traits associated with high dispersal ability would be over-represented shortly after a disturbance event occurs, while those associated with high competitive ability would have increased representation as time progresses. Additionally, it has been suggested that competitive interactions may contribute to negative co-occurrence patterns; if this is the case, negative co-occurrence patterns should also increase as time-since-disturbance increases. Here, we examine how functional trait and co-occurrence patterns change over time following a herbicide-based disturbance, compared to undisturbed vegetation, in a temperate, old-field grassland dominated by herbaceous perennials. In our study system, negative co-occurrence patterns were most pronounced in disturbed plots one year after herbicide application, consistent with several lines of evidence that dispersal can strongly impact both composition and co-occurrence patterns. Over three years post-disturbance, co-occurrence patterns in disturbed plots decreased, becoming more similar to control plots. This pattern is inconsistent with the expectation that competition contributes to negative co-occurrence patterns, at least over three growing seasons. More pronounced negative co-occurrence patterns were associated with higher species evenness among plots. Functional traits related to increased dispersal (mean seed mass, and proportion of stoloniferous/rhizomatous species) and competitive ability (mean species height, and mean specific leaf area) did not differ significantly across treatments, with the exception of mean height in the third-year post-disturbance; however, the overall trajectory of this trait was inconsistent with theoretical expectations. Overall, co-occurrence patterns changed across the gradient of time-since disturbance, but not as expected; functional trait patterns (trait means, functional diversity measures) were not responsive to our experimental disturbance gradient.

Species and functional diversity of direct‐seeded vegetation declines over 25 years

SummaryThe re‐establishment of native vegetation on disturbed land has been adopted widely as a form of ecological restoration in the past few decades. It is often suggested that establishing native plantings will lead to increasing biodiversity at restoration sites over time. However, this prediction has not been tested over long periods. Now that some pioneering projects and monitoring programs have become older, it is possible to quantify the long‐term benefits of native vegetation plantings. We asked how the plant diversity and function of 12 biodiverse native vegetation plantings has changed over approximately 30 years. We found that sites declined in measures of functional and species diversity over time. Shorter‐statured woody species were not as common at older sites. Surprisingly, sites initially seeded with a greater richness of species did not have higher standing richness at any later census period. While all sites produced net native biodiversity benefits relative to the exotic pastures they replaced, ongoing management and monitoring will be needed to ensure they continue to do so. Understanding the relationship between ageing native vegetation plantings and other components of the ecosystem (e.g., mammals, birds, invertebrates, soil, microorganisms) is a priority. Our results suggest that recruitment barriers in ex‐agricultural ecosystems are high and that the biodiversity benefits provided by shorter‐lived species will only be transient without ongoing management of these systems. Research confronting these recruitment barriers is a priority, and managers (and funders) of these kinds of restoration projects may need to be prepared for ongoing management of sites to promote lost components if they are desired as continual features of these ecosystems.

Assessing taxonomic, functional and phylogenetic diversity of giant clams across the Indo‐Pacific for conservation prioritization

AbstractAimGiant clams are iconic bivalves known to serve numerous ecological roles contributing to the functioning of coral reef ecosystems. In the next decade, giant clams will continue to face critical anthropogenic pressures from over‐exploitation for their meat and shells, the aquarium trade and global warming that threaten the persistence of their species. Here, we assess the relationships between different biodiversity components to inform conservation prioritization and management.LocationIndo‐Pacific marine realm.MethodsWe quantified taxonomic, functional and phylogenetic diversity measures throughout 25 marine provinces and assessed their relationships for all 12 giant clam species in the subfamily Tridacninae. These biodiversity measures were used to identify potentially threatened species that contribute disproportionately to trait and evolutionary diversity and to highlight areas for global conservation prioritization of giant clam species.ResultsAnalyses show positive correlations among species richness (SR), functional diversity (FD) and phylogenetic diversity (PD), with the strongest relationship between FD and PD. However, spatial patterns of higher‐than‐expected FD and PD are incongruent with SR patterns, indicating that SR omits information associated with functional and phylogenetic diversity. Among the giant clam species, Tridacna gigas and Hippopus spp. have the greatest functional and evolutionary diversity contributions within assemblies, respectively. Spatial analyses reveal that the Bay of Bengal, Andaman and numerous parts of the eastern Indo‐Pacific potentially hold higher‐than‐expected FD and PD levels relative to their SR and thus warrant more attention with respect to conserving the diversity of giant clams.ConclusionsOur findings underscore the importance of integrating functional trait contributions and evolutionary diversity into conservation planning to better differentiate giant clam assemblages, as it remains challenging to implement dedicated conservation given the limited resources. This study provides comprehensive biodiversity information for managers to initiate measures that holistically capture species' ecological and evolutionary standings across global reef ecosystems.

Bird dependence on wetlands determines functional responses to flood pulse in the Brazilian Pantanal

Hydrological regimes in floodplains are essential to support biodiversity that depend on wetlands, and understanding how these organisms are associated to this ecosystem could be useful, as they can act as important agents for the maintenance of diversity and natural processes. We aimed to assess the bird functional responses to the Pantanal flood pulse, considering the hydrological periods and three bird groups with different degrees of wetlands dependence. For this, bird survey was conducted in the Paraguay River floodplain system, covering the hydrological periods of the 2017–2018 cycle. We considered species richness, abundance, four functional diversity measures, and functional trait composition as ecological responses. Species richness was higher for bird group with lower degree of wetland dependence, mainly in drought and ebb periods. On the other hand, we found that the higher the degree of wetland dependence by birds, the higher the differences in the functional-trait values over periods. Abundance was affected by the variation of the hydrological periods for all bird groups. Bird groups had distinct niches, and functional traits associated with waterbirds were dominant in all periods. We found that degree of wetland dependence is driving the response of birds to changes in hydrological periods. Measuring only species richness may not reflect the inherent characteristics of this ecosystem. Bird groups such as waterbirds and wetland birds showed greater functional diversity throughout the hydrological periods, evidencing the importance of the flood pulse regime for species that are highly dependent on these environments and that perform many ecological services.

Resilience of Avian Communities to Urbanization and Climate Change: an Integrative Review

The concept of ecological resilience is widely used to assess how species and ecosystems respond to external stressors but is applied infrequently at the level of the community or to chronic, ongoing disturbances. In this review, we first discuss the concept of ecological resilience and methods for quantifying resilience in ecological studies. We then synthesize existing evidence for the resilience of avian communities to climate change and urbanization, two chronic disturbances that are driving global biodiversity loss, and conclude with recommendations for future directions. We only briefly discuss the theoretical framework behind ecological resilience and species-specific responses to these two major disturbances, because numerous reviews already exist on these topics. Current research suggests strong heterogeneity in the responses and resilience of bird communities to urbanization and climate change, although community disassembly and reassembly is high following both disturbances. To advance our understanding of community resilience to these disturbances, we recommend five areas of future study (1) the development of a standardized, comprehensive community resilience index that incorporates both adaptive capacity and measures of functional diversity, (2) measurement/modeling of both community resistance and recovery in response to disturbance, (3) multi-scale and/or multi-taxa studies that include three-way interactions between plants, animals, and climate, (4) studies that incorporate interactions between disturbances, and (5) increased understanding of interactions between ecological resilience and socio-ecological dynamics. Advancement in these areas will enhance our ability to predict and respond to the rapidly accelerating effects of climate change and urbanization.