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Ecological community structure, which has traditionally been described in terms of taxonomic units, is driven by dispersal and environmental filters. Traits have recently been recognized as alternative units for quantifying community parameters, but they may have important differences with taxonomic units. For example, as taxon‐based community structure is determined by the local species pool, it may be more dispersal‐limited, whereas trait‐based community structure may be more regulated by environmental conditions because traits are less tied to specific habitat locations. This implies that the relative importance of these two filters may vary depending on the units describing community structure, but no study has yet quantified how the contributions of these filters can differ. In this study, we examined zooplankton assemblages in 87 artificial reservoirs throughout the Japanese archipelago to quantify the relative importance of two filters by examining the effects of spatial configuration (reflecting dispersal filters) and biotic and abiotic variables (reflecting environmental filters) for taxon‐ and trait‐based community structure. Variation in the taxon‐based community structure was explained equally well by the spatial and the environmental variables, while variation in the trait‐based community structure was explained more by environmental variables. These results support the idea that environmental filters play a more central role in determining trait‐based community structures, and show that the relative importance of spatial and environmental filters changes with the way we define community structure. [ABSTRACT FROM AUTHOR]

The correlates of mammal species richness and community associations along elevation gradients have resulted in conflicting results within tropical systems. We surveyed the terrestrial mammal and gallinaceous bird community (>200 g body size) along transects at 4 mountain sites in Malaysian Borneo using camera traps to assess structuring of the mammal community along the elevation gradient. Between 2015 and 2021, we surveyed Bukit Lanjak (elevation 1,300 m) in Sarawak (Lanjak Entimau Wildlife Sanctuary; LEWS) and Mts. Kinabalu, Tambuyukon, and Magdalena (up to 2,400 m) in Sabah, with a total sample effort of 20,600 camera nights. We detected 48 species of mammals and 9 species of large terrestrial birds. There was mostly a common species pool across the sites, with only 9 species detected solely in LEWS and 5 species only in Sabah. Over our limited elevation range, no species were detected across the entire elevation range and no common species were confined to the highest elevation sites in Sabah or LEWS (>1,000 m). A species richness curve for each location indicated a slight peak at ~1,000 m for LEWS, but the mid-elevation peak was not evident at Sabah. The individual response curves of relative abundance to the elevation gradient for 15 species with sufficient detections were similar across sites (1 exception—Malaysian Porcupine) with 6 species showing no correlation with elevation, while 4 species increased and 4 species decreased in detections with elevation. A multivariate analysis of species detections found herbivores at lower elevations and mesocarnivores at higher elevations, while species of the same foraging guilds differed in body size at the same elevation. As opposed to studies focused on smaller vertebrate species (i.e. rodents, songbirds), larger mammal and terrestrial bird communities in these mountains did not form unique communities along the elevation gradient but did structure according to the functional traits of foraging guilds and body size. [ABSTRACT FROM AUTHOR]

Natural environments have undergone significant alteration and devastation, often becoming immersed in a matrix of anthropogenic activities. Therefore, it is imperative to ascertain whether mammals inhabit these modified areas. We present the composition of medium and large-sized terrestrial mammal species in a Cerrado area surrounded by a eucalyptus matrix. Our study area comprises a 363 ha Cerrado fragment. Surveys were conducted using 10 camera traps from December 2015 to April 2017, totaling 125 sampling stations and a sampling effort of 3,018 trap-days. We identified 19 mammal species, seven of them regionally threatened (37 %), representing 61 % of the potential species pool in the region. Omnivores and insectivores accounted for most of the recorded species. Notably, records include the Priodontes maximus, Tapirus terrestris, and Ozotoceros bezoarticus, cubs and a predation record. Given that T. terrestris was recorded only in our study and P. maximus in a single other study in the region, our findings suggest that these species can inhabit small vegetation fragments. Additionally, we include O. bezoarticus in the list of mammals inhabiting the region. Our study underscores the capacity of Cerrado fragments surrounded by silviculture to harbor a rich diversity of medium and large-sized mammals, especially considering those threatened with extinction. [ABSTRACT FROM AUTHOR]

Diversity and heterogeneity often are conflated but are fundamentally different. An aphorism proposed by Shavit and Ellison (2021; J. Phil. 118: 525–548) for distinguishing them is that ‘a zoo is diverse whereas an ecosystem is heterogeneous.' That is, a zookeeper measuring diversity simply enumerates the different types of animals; interactions are not expected to occur between animals separated by fences or other barriers. In contrast, measures of heterogeneity ought to include both interspecific interactions and relationships between species and their heterogeneous habitats. Here, we use cross‐scale, dual scaling‐law analyses of heterogeneity and diversity of animal gut microbiomes (AGMs) to address three objectives: 1) estimate the spatial heterogeneity and diversity of animal‐gut microbiomes; 2) analyze influences of phylogeny and diets on scaling of diversity and heterogeneity; 3) explore mechanistic differences between diversity and heterogeneity in AGMs. From 4903 AGM samples collected from 318 animal species covering all six classes of vertebrates and four major classes of invertebrates, we estimated that ≈640 000 operational taxonomic units (OTUs or ‘species') make up the pool of microbial species that could inhabit animal guts, among which ≈8000 are relatively common and ≈800 are dominant. The gut of any single animal, however, includes only 0.01–0.5% of the total species pool. We applied Ma's diversity‐area relationship for scaling diversity, and extend Taylor's power law and Luna et al.'s (2020; Diversity 12: 86) interaction diversity for scaling heterogeneity. At the community scale, phylogeny significantly influenced heterogeneity, but diets did not. Phylogeny and diets had limited influence on diversity at both community and landscape scales. We demonstrated that diversity and heterogeneity measure two different properties. Further, differences in scaling of diversity and heterogeneity are a result of heterogeneity being primarily the result of evolved dispersal behavior and interspecific interactions, whereas diversity results from abundances controlled on ecological time scales. [ABSTRACT FROM AUTHOR]

At the nearly pristine hydrothermal vents of the deep sea, highly endemic animals depend upon bacteria nourished by hydrothermal fluids that emerge as outflows from the seafloor. These animals are remarkable in tolerating extreme conditions, including high heat, toxic reduced sulfide, and low oxygen. Here, we test whether the extreme vent environment has selected for functionally similar species across the world's deep ocean, despite well-established global geographic patterns of high phylogenetic distinctness. High functional redundancy in species pools within regions suggests that the extreme environments select for species with specific traits. Yet, some regions emerge as functional hotspots where species pools with distinct functional trait compositions may represent geological idiosyncrasies of the habitats. Moreover, many species are functionally unique, an outcome of low species richness in a system where the species pool is small at all scales. Given the high proportion of functionally unique species, simulated species extinctions indicate that species losses would rapidly translate to the elimination of functionally irreplaceable species and could tip vent systems to functional collapse. Ocean changes and human-induced threats are expected to significantly impact many vent species as human activities expand in the remote deep sea. The opportunity exists now to take precautionary actions to limit the rates of extinction now ubiquitous in more accessible areas of Earth. [ABSTRACT FROM AUTHOR]

The relative importance of the different processes that determine the distribution of species and the assembly of communities is a key question in ecology. The distribution of any individual species is affected by a wide range of environmental variables as well as through interactions with other species; the resulting distributions determine the pool of species available to form local communities at fine spatial scales. A challenge in community ecology is that these interactions (e.g. competition, facilitation, etc.) often are not directly measurable. Here, we used hierarchical modelling of species communities (HMSC), a recently developed framework for joint species distribution modelling, to estimate the role of biotic effects alongside environmental factors using latent variables. We investigate the role of these factors determining species distributions in communities of Artiodactyla, Perissodactyla and Proboscidea in the Afrotropics, an area of peak species richness for hoofed mammals. We also calculate pairwise trait dissimilarity between these species, from a mixture of morphological and behavioural traits, and investigate the relationship between dissimilarity and estimated residual co‐occurrence in the model. We find that while ungulate distributions appear to be predominantly determined (~ 70%) by climatic variables, such as precipitation, a substantial proportion of the variance in ungulate species distributions (~ 30%) can also be attributed to modelled latent variables that likely represent a combination of dispersal barriers and biotic factors. Although we find only a weak relationship between residual co‐occurrence and trait dissimilarity, we suggest that our results may show evidence that biotic factors, likely influenced by historical barriers to species dispersal, are important in determining species communities over a continental area. The HMSC framework can be used to provide insight into factors affecting community assembly at broad scales, and to make more powerful predictions about future species distributions as we enter an era of increasing impacts from anthropogenic change. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms behind biodiversity dynamics is central to assessing and forecasting anthropogenic impacts on ecological communities. However, the manner in which external environmental drivers act in concert with intrinsic ecological processes to influence local temporal turnover is currently largely unexplored. Here, we determine how human impacts affect multiple metrics of bird community turnover to establish the ecological mechanisms behind compositional change. We used US Breeding Bird Survey data to calculate transect‐level rates of three measures of temporal species turnover: (1) "short‐term" (initial rate of decline of Sørensen similarity), (2) "long‐term" (asymptotic Sørensen similarity), and (3) "throughput" (overall species accumulation rate from species–time relationship exponents) over 2692 transects across 27 regional habitat types. We then hierarchically fit linear models to estimate the effect of anthropogenic impact on these turnover metrics, using the Human Modification Index proxy, while accounting for observed species richness, the size of the species pool, and annual environmental variability. We found broadly consistent impacts of increased anthropogenic pressures across diverse habitat types. The Human Modification Index was associated with greater turnover at long timescales, but marginally slower short‐term turnover. The species "throughput" (accumulation rate) was not notably influenced. Examining anthropogenic impacts on different aspects of species turnover in combination allows greater ecological insight. Observed human impacts on short‐term turnover were the opposite of existing expectations and suggest humans are disrupting the background turnover of these systems, rather than simply driving rapid directed turnover. The increased long‐term turnover without concurrent increases in species accumulation implies human impacts lead to shifts in species occurrence frequency rather than simply greater arrival of "new" species. These results highlight the role of intrinsic dynamics and caution against simple interpretations of increased species turnover as reflections of environmental change. [ABSTRACT FROM AUTHOR]

Utilizing ecosystems' natural recovery potential is crucial for enhancing the scale and efficacy of restoration efforts. However, this potential is currently underutilized in restoration ecology, and barriers to natural species recruitment remain poorly understood. In this study, we develop an analytical framework that combines trait‐based and dark diversity approaches to evaluate understory plant community recovery in smelter‐impacted forests and identify factors limiting recovery for absent species. A community completeness index (CCI) was calculated in 18 naturally recovering smelter‐impacted forests and three reference forests in Sudbury, Ontario, Canada. The CCI was used to identify sites that deviate the most from their target communities and was compared to traditionally used indicators of plant recovery. Community weighted means (CWM) of traits for observed and dark diversity species were compared, and principal components analysis was used to identify relationships between traits of observed and missing species among study sites. Species unable to recover passively (i.e. with high dark diversity probabilities) were generally tall and/or large seeded. Understory plant community recovery was structured along two functional gradients, plant economics and size, which both coincided with distance to the smelter. Dark diversity and trait analyses were useful for identifying barriers to natural recovery and, therefore, providing guidance on targeted restoration actions. We conclude by discussing the limitations and opportunities of the dark diversity approach in a restoration context, highlighting the importance of carefully defining habitat‐specific species pools and critically assessing the ecological significance of dark diversity probabilities. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Large quantities of diverse native seeds are required to scale up global restoration efforts. However, it remains unclear for many ecosystems how the diversity of available seed in commercial stocks reflects the composition of the ecosystems where vegetation is being remade. This study highlights existing shortfalls in the diversity of seed presently available for use in restoration and identifies gaps in the seed supply chain while providing a new method for optimising species selection given these constraints. This work underscores how improved collaboration between stakeholders is required to strengthen the seed supply chain and help remake functionally diverse vegetation. Summary: Restoration using native seed is frequently implemented to restore degraded ecosystems. However, it remains unclear how constraints on the diversity of germplasm available for use in restoration may limit the recovery of both species and plant functional diversity.Using a dataset of seed availability for Australia's major vegetation types, we explore variation in the diversity and breadth of functional traits (leaf mass per area, seed mass, plant height) for species where seed is available on commercial markets relative to unavailable. Using these data, we simulate theoretical seed mixes derived from two species pools: (1) constrained by the current market of commercially available seed, and (2) assuming all native species can be planted; then we compare differences in functional diversity (dispersion) as an exercise to explore possible limitations within the current seed supply.Seed from only 12% of Australian plant species (2992 species) is presently available for immediate purchase. Seed was more frequently available for trees and shrubs than for understorey species. Available species were on average taller, with thicker, longer‐lived leaves than unavailable species. Overall, functional dispersion was lower for seed mixes generated using available seed compared with those drawn from all species.Solutions are required to address seed shortfalls so that plantings are not only species rich but also functionally diverse. We develop two options: (1) quantifying and addressing gaps in the seed supply chain that currently limit the capacity for practitioners to restore diverse vegetation; and (2) applying a trait‐informed species‐selection method to plantings that maximises functional diversity using available seed. [ABSTRACT FROM AUTHOR]

Unraveling the mechanisms of community assembly in different ecosystems is a central ecological issue. Soil depth, which is the predominant characteristic of karst regions, possibly affects community assembly from the regional species pool into local communities. However, the influence of karst soil depth on plant community assembly mechanisms remains unclear. We investigated the community functional traits of karst shrublands by calculating community-weighted mean (CWM) traits for leaf dry matter content (LDMC), specific leaf area (SLA), leaf carbon content (LCC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), and leaf potassium content (LKC). To explore the assembly pattern of karst shrublands, we assessed the extent of trait divergence or convergence using trait-based null model analyses. Additionally, we examined how community functional traits and assembly patterns changed with varying local soil depths. Karst shrublands were found to exhibit CWM trait combinations characterized by high LDMC and LCC, as well as low SLA, LNC, LPC, and LKC to adapting to harsh environments. Furthermore, the CWM of LDMC, LCC, LCC/LNC ratio, and LCC/LPC ratio significantly decreased, while SLA and LNC in karst shrublands significantly increased along soil depth gradients. This indicates that, as soil conditions improved, the karst shrubland community shifted from a conservative survival strategy to a resource-acquisition strategy. Overall, the convergence pattern prevailed in the karst shrubland communities for most leaf traits. As the karst soil depth increased, the traits of the shrubland communities shifted from a convergence pattern toward a neutral assembly. These results demonstrate for the first time that species were primarily assembled into karst shrubland communities through environmental filtering, while the importance of environmental filtering in the assembly process gradually weakened with increasing soil depth. Our study underlines the necessity of increasing soil quantity to allow more species from the regional species pool to enter local shrublands, thereby promoting karst community succession. [ABSTRACT FROM AUTHOR]

Estimates of dark diversity, species that belong to a given species pool but are not present locally, can help to understand how environmental conditions influence species distribution. However, it remains uncertain whether dark diversity can predict the absence of indicator species in preserved environments after environmental changes. We explored the sensitivity of dark diversity (the set of species absent from a particular area), in detecting the absence of Zygoptera (Odonata) indicative of preserved forest environments in altered habitats, and the influence of sample coverage on the detected patterns. We sampled 98 streams in the Amazon region, where the dark diversity of Zygoptera was estimated based on probabilistic species co-occurrence patterns using the Beals index, encompassing 16 species in the Santarém/Belterra region and 23 species in the Paragominas region. The mean total richness of observed Zygoptera species in Paragominas, 42.7 species, and Santarém/Belterra, 25.93 species, was higher than the estimated mean dark diversity for the two study sites, which were 12.32 and 12.20 species, respectively. The dark diversity was not effective in detecting the absence of forest-indicator Zygoptera in human-altered streams and exhibited a positive relationship between Zygoptera dark diversity and species common to different environments concerning environmental integrity only in Paragominas, but not in Santarém. We found that there is a possibility that observed values of dark diversity may occasionally be subject to sampling coverage biases. In this regard, we suggest considering sampling coverage alongside field-collected biological datasets to assess whether it is related to dark diversity. [ABSTRACT FROM AUTHOR]

Both regional species pool and local community assembly mechanism drive the microbial diversity patterns across geographical gradients. However, little has been done to separate their effects on the β diversity patterns of microbial communities involved in nitrogen (N) cycling in river ecosystems. Here, we use high‐throughput sequencing of the archaeal amoA, bacterial amoA, nirK, and nirS genes, null model, and neutral community model to distinguish the relative importance of species pool and local assembly processes for ammonia‐oxidizing and denitrifying communities in river wetlands along a latitudinal gradient in eastern China. Results indicated that the β diversity of the nirS‐type denitrifying community co‐varied with γ diversity and environmental heterogeneity, implying that regional species pool and heterogeneous selection explained variation in β diversity. However, the β diversity of ammonia‐oxidizing and nirK‐type denitrifying communities did not correlate with γ diversity and environmental heterogeneity. The continuous hump distribution of β deviation along the latitudinal gradient and the lower species dispersal rate indicated that the dispersal limitation shaped the variation in β diversity of ammonia‐oxidizing and nirK‐type denitrifying communities. Additionally, biotic interactions drove ammonia‐oxidizing and nirS‐type denitrifying communities by influencing species co‐occurrence patterns. Our study highlights the importance of regional species pool and local community assembly processes in shaping geographical patterns of N‐cycling microorganisms and extends knowledge of their adaptability to a continuously changing environment on a large scale. [ABSTRACT FROM AUTHOR]

Large rivers throughout the world have been transformed by anthropogenic stressors that are known to influence the structure and composition of fish assemblages. Management of large rivers requires balancing socio-economic and political considerations with biodiversity conservation efforts. By exchanging best management practices between rivers, management efforts can be improved. However, data limitations have largely prevented comparative analyses among fish assemblages in large rivers, potentially limiting the effectiveness of shared management strategies. To improve understanding of the similarities and differences between the Upper Mississippi and Yangtze Rivers, we (1) compared environmental variables and functional traits of fish assemblages between the two systems, (2) identified traits responsible for distinguishing functional groups from one another, and (3) investigated relationships between similar functional groups of fishes and environmental variables to establish expectations for how fish assemblages in large rivers might respond to anthropogenic stressors. Regional species pools in the Upper Mississippi and Upper Yangtze Rivers were characterized by a similar composition of functional traits; the majority of species were omnivorous, had affinities for gravel or sand substrates, and produced sinking eggs. Few species were pelagic, planktivorous, or herbivorous. Functional groups in both rivers were primarily distinguished according to species' trophic habits and substrate preferences, with secondary contributions from species’ water column positions and life history characteristics. Pelagic planktivores and small-bodied guarders with an affinity for structural habitat complexity tended to increase downriver in both systems, in direct association with total phosphorus concentrations, agricultural land use, and temperature. In contrast, proportions of lithophilic species with affinities for gravel or cobble substrates were highest in segments located furthest upriver. By highlighting the sensitivity of different groups of fishes to anthropogenic stressors, we provide insights into the functional ecology of fishes inhabiting the Mississippi and Yangtze Rivers. [ABSTRACT FROM AUTHOR]

Defaunation is an increasingly pervasive process, reaching ever larger spatial scales worldwide. We integrated data on thousands of putative local mammal assemblages across the Neotropics into 518 metacommunities to predict the phylogenetic trait‐based effects of regional defaunation—here defined as meta‐extirpation (i.e. extinction at the metacommunity level)—on dozens of putative ecosystem services (ESs). Further, based on 1029 real‐world mammal assemblages coalesced into 236 metacommunities, we assessed the spatial extent of meta‐extirpations across the Neotropics, while empirically quantifying losses in ESs in comparison with putative scenarios. Using observed data, we also sought to understand changes in the mean body size of metacommunities for different dietary guilds. We examined patterns of mammal diversity, evaluated the erosion of ESs based on ecological networks and measured the relationships between diversity metrics and ESs via dissimilarity arrangements and generalized linear models. Meta‐extirpation regimes lead to a mean loss of 49.6% of the ESs provided by Neotropical mammals within metacommunities, whereas real‐world meta‐extirpations derived 47.2% of ES loss. We show that simulated meta‐extirpations penalizing large‐bodied species, induced the most severe losses in ESs. Regional‐scale meta‐extirpations lead to changes in the metabolic allometry and trophic structure of consumers, inducing significant metacommunity downsizing. We conclude that once‐thriving mammal‐mediated roles in natural ecosystems are fading, with significant consequences for human livelihoods. Many mammal populations have succumbed in several Neotropical ecoregions; so it is critical to protect representative fractions of Neotropical landscapes and regional species pools. Finally, we reinforce the appeal for effective conservation action, given that meta‐extirpations are already a global reality. [ABSTRACT FROM AUTHOR]

Vertical stratification is a property of forest habitats related to the differential distribution of organisms according to the variation in the conditions, from the understory to the canopy. Here, we aimed to test whether butterfly assemblages from highly disturbed forests maintain the pattern of vertical stratification. We hypothesized that degraded forests would not exhibit vertical stratification due to the low variation in the microhabitat conditions along the vertical gradient, resulting from the canopy openness. To test this, we sampled fruit-feeding butterflies with bait traps, alternately disposed between the understory and canopy of three secondary forest fragments in a very fragmented Atlantic Forest landscape, for one year. We found that the vertical strata differed in terms of species composition, with a high contribution by the nestedness component on the beta diversity spatial variation. The understory assemblages had a higher abundance and were more diverse than the upper stratum. We demonstrated that vertical stratification is maintained even in disturbed forests; however, this does not necessarily provide support for a good quality and functioning ecosystem in these habitats. The butterfly assemblages recorded here are a subset of the species pool that inhabits conserved remnants. Thus, even being represented by species commonly found in disturbed habitats, the dynamic of vertical stratification of assemblages remains. [ABSTRACT FROM AUTHOR]

Contact with environmental microbial communities primes the human immune system. Factors determining the distribution of microorganisms, such as dispersal, are thus important for human health. Here, we used the relative number of bacteria shared between environmental and human samples as a measure of bacterial dispersal and studied these associations with living environment and lifestyles. We analyzed amplicon sequence variants (ASVs) of the V4 region of 16S rDNA gene from 347 samples of doormat dust as well as samples of saliva, skin swabs, and feces from 53 elderly people in urban and rural areas in Finland at three timepoints. We first enumerated the ASVs shared between doormat and one of the human sample types (i.e., saliva, skin swab, or feces) of each individual subject and calculated the shared ASVs as a proportion of all ASVs in the given sample type of that individual. We observed that the patterns for the proportions of shared ASVs differed among seasons and human sample type. In skin samples, there was a negative association between the proportion of shared ASVs and the coverage of built environment (a proxy for degree of urbanization), whereas in saliva data, this association was positive. We discuss these findings in the context of differing species pools in urban and rural environments. IMPORTANCE Understanding how environmental microorganisms reach and interact with humans is a key question when aiming to increase human contacts with natural microbiota. Few methods are suitable for studying microbial dispersal at relatively large spatial scales. Thus, we tested an indirect method and studied patterns of bacterial taxa that are shared between humans and their living environment. [ABSTRACT FROM AUTHOR]

Microbial biostalactites and streamers commonly grow at iron seepages in abandoned mines worldwide. This study addresses the diversity and composition of these simple prokaryotic communities, which thrive in pH ranges from 2.4 to 6.6 across six different mines. Our analysis of 85 communities reveals that a pH of approximately 3.2 is a critical threshold where alpha and beta diversity change discretely. Below this pH, the average number of ASVs per sample is 2.91 times lower than above this boundary. Autotrophs, heterotrophs, and symbionts of eukaryotes originate from nearly non‐overlapping species pools in the two habitat types that differ only in pH. Communities below pH 3.2 further divide into two distinct groups, differing in diversity, taxonomic, and functional composition. Both types of communities coexist within the same stalactites, likely corresponding to zones where the capillary structure of the stalactite is either perfused or clogged. These findings indicate that microbial community structure can be significantly influenced by the intricate spatial organization of the ecosystem, rather than solely by measurable environmental parameters. [ABSTRACT FROM AUTHOR]

Nature-based solutions have been promoted as an effective strategy to address climate impacts, including urban temperature reduction. In this paper, we analyze the impacts of the introduction of street trees on temperature (Universal Thermal Climate Index, UTCI) for three different dates, 2000, 2023, and 2050. A 3D model was developed in Rhinoceros software for a part of George Town, on Penang Island. Four different sections of streets were simulated after integration of the model with the Grasshopper plug-in, where a parametric system was built for temperature measurements based on simulations in the Ladybug and Honeybee plug-ins. The tree species used were selected from a pool of tree species commonly planted in urban settings in Malaysia that have low and medium sensitivity to climate impacts. The results show a maximum reduction of 7 °C between 2000 and 2050, achieved on a street with an NW–SE orientation that was planted with three rows of trees. The minimum UTCI reduction achieved was 3 °C, between 2023 and 2050, in a street with NW–SE orientation that was planted with one tree row. The two streets with a SW–NE orientation showed a 5 °C temperature reduction between 2023 and 2050. Both streets have only one row of trees but different species and sizes, with the bigger trees reducing the temperature in a slightly larger area. The results show the importance of introducing and safeguarding street trees to reduce urban temperatures in the country, potentially keeping temperatures below life-threatening levels, thereby safeguarding urban health, while also reducing costs of energy consumption. Solar orientation, the number of tree rows, and their distribution impact the outcomes. The findings provide useful guidance for climate-conscious urban planning practices in Malaysia. [ABSTRACT FROM AUTHOR]

Revealing the mechanisms underlying community organization has long been a central interest for ecologists and biogeographers. Recent findings have suggested that different dimensions of biodiversity may be shaped by contrasting ecological processes, offering complementary insights about community assembly. However, studies integrating multiple diversity facets across the Qinghai‐Tibetan Plateau (QTP) remain insufficient. We combined multiple analytical frameworks to unravel the patterns (taxonomic, functional and phylogenetic) and correlates (local environment, land use and dispersal pathways) of aquatic arthropod diversity in lotic (stream) and lentic (wetland) ecosystems of the QTP. We observed strong phylogenetic signals in most functional traits, pointing to the influence of evolutionary processes on these faunas. Null models indicated that community structure in most streams and wetlands was mostly the result of random draws from the regional functional and phylogenetic species pool. The prevalence of stochasticity was most likely associated with the interplay of the paleogeographical history, the extremely harsh environmental conditions at high elevations and the subsequent impoverishment of the regional species pool. However, some streams and wetlands also exhibited phylogenetic overdispersion and functional clustering, emphasizing the potential importance of competitive exclusion and habitat filtering, respectively. Variation partitioning further revealed that both environmental filtering and dispersal limitation accounted for the spatial variation of diversity measures, with local environment overriding the effects of space and catchment land use. Overall, this study improves our understanding of community organization and diversity patterns in environmentally extreme alpine catchments, with broad implications for the conservation and management of one of the world’s most important high‐altitude treasures. [ABSTRACT FROM AUTHOR]

Background: DNA metabarcoding applies high-throughput sequencing approaches to generate numerous DNA barcodes from mixed sample pools for mass species identification and community characterisation. To date, however, most metabarcoding studies employ second-generation sequencing platforms like Illumina, which are limited by short read lengths and longer turnaround times. While third-generation platforms such as the MinION (Oxford Nanopore Technologies) can sequence longer reads and even in real-time, application of these platforms for metabarcoding has remained limited possibly due to the relatively high read error rates as well as the paucity of specialised software for processing such reads. Results: We show that this is no longer the case by performing nanopore-based, cytochrome c oxidase subunit I (COI) metabarcoding on 34 zooplankton bulk samples, and benchmarking the results against conventional Illumina MiSeq sequencing. Nanopore R10.3 sequencing chemistry and super accurate (SUP) basecalling model reduced raw read error rates to ~ 4%, and consensus calling with amplicon_sorter (without further error correction) generated metabarcodes that were ≤ 1% erroneous. Although Illumina recovered a higher number of molecular operational taxonomic units (MOTUs) than nanopore sequencing (589 vs. 471), we found no significant differences in the zooplankton communities inferred between the sequencing platforms. Importantly, 406 of 444 (91.4%) shared MOTUs between Illumina and nanopore were also found to be free of indel errors, and 85% of the zooplankton richness could be recovered after just 12–15 h of sequencing. Conclusion: Our results demonstrate that nanopore sequencing can generate metabarcodes with Illumina-like accuracy, and we are the first study to show that nanopore metabarcodes are almost always indel-free. We also show that nanopore metabarcoding is viable for characterising species-rich communities rapidly, and that the same ecological conclusions can be obtained regardless of the sequencing platform used. Collectively, our study inspires confidence in nanopore sequencing and paves the way for greater utilisation of nanopore technology in various metabarcoding applications. [ABSTRACT FROM AUTHOR]

Knowledge about how ecological networks vary across global scales is currently limited given the complexity of acquiring repeated spatial data for species interactions. Yet, recent developments in metawebs highlight efficient ways to first document possible interactions within regional species pools. Downscaling metawebs towards local network predictions is a promising approach to using the current data to investigate the variation of networks across space. However, issues remain in how to represent the spatial variability and uncertainty of species interactions, especially for large-scale food webs. Here, we present a probabilistic framework to downscale a metaweb based on the Canadian mammal metaweb and species occurrences from global databases. We investigated how our approach can be used to represent the variability of networks and communities between ecoregions in Canada. Species richness and interactions followed a similar latitudinal gradient across ecoregions but simultaneously identified contrasting diversity hotspots. Network motifs revealed additional areas of variation in network structure compared with species richness and number of links. Our method offers the potential to bring global predictions down to a more actionable local scale, and increases the diversity of ecological networks that can be projected in space. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'. [ABSTRACT FROM AUTHOR]

Neovaginas are surgically constructed to correct uterovaginal agenesis in women with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome or as part of gender-affirming surgery for transfeminine individuals. Understanding the assembly of the neovaginal microbiota is crucial for guiding its management. To address this, we conducted a longitudinal study on MRKH patients following laparoscopic peritoneal vaginoplasty. Our findings reveal that the early microbial assemblage exhibited stochastic characteristics, accompanied with a notable bloom of Enterococcus faecalis and genital Mycoplasmas. While both the pre-surgery dimple microbiota and the fecal microbiota constituted the primary species pool, the neovaginal microbiota developed into a microbiota that resembled that of a normal vagina at 6–12 months post-surgery, albeit with a bacterial vaginosis (BV)-like structure. By 2–4 years post-surgery, the neovaginal microbiota had further evolved into a structure closely resembling with the homeostatic pre-surgery dimple microbiota. This concords with the development of the squamous epithelium in the neovagina and highlights the pivotal roles of progressive selective forces imposed by the evolving neovaginal environment and the colonization tropism of vaginal species. Notably, we observed that strains of Lactobacillus crispatus colonizing the neovagina primarily originated from the dimple. Since L. crispatus is generally associated with vaginal health, this finding suggests potential avenues for future research to promote its colonization. Neovaginas are surgically constructed to correct uterovaginal agenesis in women with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome. Here, in a longitudinal study, the authors characterize the dynamics of neovaginal microbiota assembly, showing resemblance to normal vaginal flora at 6-12 months post-surgery, albeit with a bacterial vaginosis-like structure, and further developed into a structure resembling that of the homeostatic pre-surgery dimple microbiota by 2-4 years post-surgery. [ABSTRACT FROM AUTHOR]

While transect walks have long been the preferred monitoring method for many flying insect taxa, malaise traps combined with DNA metabarcoding have gained growing prominence. However, it remains unclear whether both methods reveal comparable species richness and the same ecological drivers along environmental gradients.We selected three groups of pollinators (wild bees, hoverflies and butterflies) and one group of herbivores (grasshoppers) as functionally important and conservation‐relevant model groups, comparing results of both methods along an elevational gradient in the German Alps.Across the study region, both methods detected a similarly high species richness of pollinators with ~50% overlap of species pools, but transect walks revealed more species per site, especially in higher elevations and under low temperatures. Body size spectra differed between methods, with on average more large butterfly and more small bee species in transect walks. Nevertheless, temperature and flower richness were consistent drivers of pollinator richness, independent of the sampling method. Grasshopper richness from transect walks was considerably higher than from malaise traps. Both methods identified temperature and only malaise traps also identified management as drivers of grasshopper richness.We conclude that malaise traps are principally suitable substitutes for the more time‐consuming pollinator transect walks. However, the effectiveness of these passive traps is more susceptible to changes in sampling temperature, and in some pollinator groups, body size classes are presented differently, which is important to consider during analyses. For grasshoppers, transect walks appear to be more suitable to assess species richness, as considerably more species can be monitored. [ABSTRACT FROM AUTHOR]

Aim: Island biological communities are considered to comprise non‐random assemblages from surrounding source pools, but whether they converge towards predictable structural properties remains unclear. Here, we (i) test whether insular communities of land snails converge towards similar functional and/or taxonomic properties and (ii) evaluate whether island functional diversity is determined by island biogeographical characteristics such as area and distance to the pool as well as human‐related variables. Location: Sixty‐six continental Aegean islands. Taxon: Land snails. Methods: We compiled a database of two morphological traits with functional significance (shell height and width) for 163 island species and 1529 species from the major species pools. We quantified inter‐specific morphological dissimilarity between pairs of islands (turnover), using a modified index of the mean nearest taxon distance. We tested for functional and taxonomic convergence using null models and assessing whether overall mean turnover among islands and pairwise island‐by‐island turnover were lower than expected by chance. We performed multiple regression analyses to test whether functional diversity metrics scale with island biogeographical characteristics and human‐related variables. Results: Our analyses provide strong evidence that communities of land snails across the Aegean islands converge towards non‐random functional properties and taxonomic structure. At the island level, a wide range of different shell shapes is observed, indicating greater functional richness than expected by chance. Regression analyses showed that island area is the only efficient predictor of functional diversity, indicating that available ecological/resource space is of central importance in driving the assembly of different shell shapes. Main Conclusions: Our findings, consistent with previous studies of other taxa from oceanic islands, highlight that island species communities are not randomly assembled and display convergence in their functional and taxonomic composition. Integrating functional diversity metrics within biogeographic analyses has the potential to further our understanding of island biodiversity patterns. [ABSTRACT FROM AUTHOR]

Aim: Revealing the role of regional species pool size in community assembly rules is essential for extending the species‐pool framework to large‐scale community ecology, and thus for more comprehensive understanding of biodiversity formation. However, little has been done to couple the regional species‐pool effect into local ecological processes in soil fungal communities, which play essential roles in ecosystems worldwide. Here, we performed large‐scale soil surveys of fungal communities to examine the linkage between regional species pool size and Dispersal–Selection Relationships (DSRs), and their relations to community structure. Location: China. Time period: July–August 2019. Major taxa studied: Fungal communities. Methods: By conducting the nationwide soil survey of ~1200 samples from various ecosystems across China, including agricultural, forest, grassland, and wetland soils, we examined the linkage between regional species pool size and DSRs, and their relationship to fungal community structure. Results: We found that selection was negatively related to dispersal, which was consistent with the general view that the strength of selection is weakened by dispersal homogenization, and that this relationship was stronger in regions with larger species pools. Moreover, an increase in community dispersion was correlated with stronger effect size of DSRs, implying greater heterogeneity among fungal communities under larger species pools. Main conclusions: Our study clearly illustrates the association of regional species pool size with local assembly rules and community formation of soil fungi across terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Clarifying the fate of different nitrogen (N) species in different pools of terrestrial ecosystems is a prerequisite for a comprehensive understanding of the influence of human activities on the N cycle. Grazing has always been an important way of grassland management for centuries in the temperate grasslands of North China. However, how grazing regimes affect the N fate of urea derived from the livestock in the plant–soil systems of grazed grasslands remains poorly understood. Therefore, an in situ three‐factor (grazing regime, soil depth, and sampling time) 15N‐labeling experiment in a temperate steppe was conducted to answer this question. After 48 days of 15N labeling, the 15N recovered in shoots under no grazing (7.3% ± 1.8%) was approximately 2.3 times of that under rotational (3.2% ± 0.4%) and 2.5 times of that under continuous overgrazing (2.9% ± 0.5%). More 15N was recovered in roots under rotational than continuous overgrazing (19.8% ± 2.4% vs. 10.4% ± 0.5%, respectively), indicating that rotational overgrazing could promote more N retention in the roots. However, the 15N recovered in the soil was lower under continuous (23.7% ± 2.0%) than that of no grazing (42.0% ± 5.6%). Additionally, overgrazing reduced the magnitude of the soil active N pool in microbial biomass N and soluble N relative to no grazing. The grazing regimes would have significantly influenced both the soil and plants. That is to say, grazing regimes have directly impacted plant growth, and subsequently indirectly affected soil properties. Overgrazing often led to excessive vegetation consumption, resulting in decreased soil water content (SWC) and reduced soil organic carbon (SOC), ultimately caused alterations in plant species composition. The retention of 15N within the plant–soil system under continuous overgrazing was notably lower compared to that of no grazing. Continuous overgrazing has led to a shift in the dominant plant species from Leymus chinensis to Stipa grandis, by decreasing the proportion of perennial grasses by 10%, and increasing the annual and biennial plants by 8%. The fate of 15N was also altered in response to the variations in grazing regimes. Consequently, the recovery of 15N within the plant–soil system under continuous overgrazing was significantly lower compared to that of no grazing. In conclusion, overgrazing reduces the recovery of 15N within the plant–soil system in the temperate steppe, and rotational grazing is more preferable over continuous grazing as it could promote higher N retention in grassland ecosystems. [ABSTRACT FROM AUTHOR]

Bamboo fibres, which are widely regarded as a contemporary environmentally sustainable resource, have been utilised in various industries including construction materials and packaging sectors. Malaysia possesses a diverse array of bamboo species, rendering it a significant resource for exploration. Five out of the 69 bamboo species discovered in Malaysia were selected for their suitability and availability in the pulp and paper industry, considering properties such as high cellulose content and long fibers. The objective of this study is to conduct a comprehensive analysis of the morphological, physiochemical, thermal, and chemical properties of five specific bamboo species that are often found in Malaysia: Gigantochloa scortechinii (GS), Gigantochloa wrayi (GW), Gigantochloa levis (GL), Schizostachyum grande (SG) and Dendrocalamus asper (DA). Selected from a pool of 69 species based on their availability, these various types of bamboo were subjected to analysis using advanced scientific techniques such as Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), and X-ray Diffraction (XRD). Furthermore, a chemical composition study was performed to clarify the presence of cellulose, hemicellulose, lignin, and ash in all five species. By employing various analytical methodologies, this study investigates and records the properties offered by the bamboo species, providing a significant contribution to the comprehension and knowledge of their potential applications across diverse disciplines. This holds relevance as all five bamboo species are readily available but remain underutilized for further applications in various fields especially in packaging industries. [ABSTRACT FROM AUTHOR]

Ecological risk assessments for potential pesticide impacts on species listed as threatened or endangered must ensure that decisions to grant registration or establish water quality standards will not jeopardize species or their critical habitats. Pesticides are designed to affect pest species via physiological pathways that may be shared by some nontarget species for which toxicity data are usually unavailable, creating a need for robust methods to estimate acute and chronic toxicity with minimal data. We used a unique probabilistic approach to estimate the risk of chronic effects of two organophosphate (OP) pesticides on the vernal pool fairy shrimp Branchinecta lynchi. Acute toxicity estimates were derived from Monte Carlo (MC) sampling of acute toxicity distributions developed from interspecies relationships using surrogate species. Within each MC draw, acute values were divided by an acute to chronic ratio (ACR) sampled from a distribution of ACRs for OP pesticides and invertebrates, producing a distribution of chronic effects concentrations. The estimated exposure concentrations (EECs) were sampled from distributions representing different environmental conditions. Risk was characterized using probability distributions of acute toxicity, ACRs, and EECs in a probabilistic analysis, as well as partial probabilistic variations that used only some distributions whereas some variables were used deterministically. A deterministic risk quotient (RQ) was compared with the results of probabilistic methods to compare the approaches. Risk varied across exposure scenarios and the number of variables that were handled probabilistically, increasing as the number of variables drawn from distributions increased. The magnitude of RQs was not correlated with the probability that EECs would exceed chronic thresholds, and comparison of the two approaches demonstrates the limited interpretability of RQs. Our novel probabilistic approach to estimating chronic risk with minimal data incorporates uncertainty underlying both exposure and effects assessments for listed species. Integr Environ Assess Manag 2024;20:1654–1666. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Key Points: Chronic risk estimates are important for ecological risk assessments (ERAs), and we present a novel approach to evaluating chronic risk using minimal data incorporating the distributions of effects and environmental exposure concentrations.Ecological risk assessment for pesticides potentially affecting a listed vernal pool fairy shrimp species is used as a case study to demonstrate our approach that is applicable to ERAs in general.Probabilistic approaches incorporate real‐world uncertainty into the effects and exposure assessments for ERAs required by different regulatory authorities.Protection of listed species from jeopardy under the Endangered Species Act will benefit from the application of probabilistic approaches to ERAs that consider variability and uncertainty in effects and environmental exposure concentrations. [ABSTRACT FROM AUTHOR]

This study investigates within-site variation in the diversity and composition of aboveground vegetation and seed bank in intensively managed wet grasslands of north-western Germany, comparing field edges, field margins and field interiors. We tested the hypothesis that unfertilized buffer strips at field edges function as refugia of characteristic species even in grasslands that are managed intensively for silage production. In 55 grassland sites on each marsh and moor soils, respectively, we conducted vegetation surveys, seed bank analyses and soil chemical measurements in field edge, margin and interior plots, and searched for the factors causing within-site variation in vegetation composition. The total species pool was small at the 110 sites, i.e. 148 species in the aboveground vegetation and 107 species in the seed bank, demonstrating severe impoverishment. The α-diversity decreased from 23 species (median) per 200 m2 at the edge to 15 species in the interior, with 38 species occurring only at field edges. The number of species with conservation value was very low in aboveground vegetation and seed bank and was only slightly higher at the edge than in the interior. Soil P availability was ca. 30% lower at the unfertilized edges than in the interior. We conclude that unfertilized buffer strips at grassland edges may help reducing nutrient leaching from high-input grassland systems, but they have mostly lost their refugial function for phytodiversity after decades of intensive management. Restoration efforts with seed or green hay transfer from richer source habitats are needed to promote biodiversity in field-edge buffer strips. [ABSTRACT FROM AUTHOR]

Light availability and habitat complexity are two key drivers of community assembly. Urbanisation has been shown to affect both, with important consequences to ecological communities. On the intertidal, for instance, studies have shown that light intensity is greater on natural rocky shores than on less complex artificial habitats (seawalls), though different habitats can also experience similar light intensities, for example when shaded by urban structures. Understanding therefore how these factors individually, and combined, affect communities is important to understand the mechanisms driving changes in community structure, and consequently provide solutions to tackle the increasing homogenisation of habitats and lightscapes in urbanised spaces through smart infrastructure designs. Here, we assessed how different light levels affect the recruitment of communities in rock pools and on emergent rock on an intertidal rocky shore. We cleared 30 patches of emergent rock and 30 rock pools and manipulated light using shades with different light transmissions (full light, procedural control, 75%, 35%, and 15% light transmission, full shade) and assessed mobile and sessile communities monthly for 6 months. Effects of reducing light levels were generally stronger on rock than in pools. Fully shaded plots supported double the amount of mobile organisms than plots in full sunlight, in both habitats. Algal cover was higher in pools compared to rock, and at intermediate light levels, but effects varied with site. This study highlights the importance of variable light conditions and different habitats for rocky shore communities, which should be considered in future coastal developments to retain natural biodiversity. [ABSTRACT FROM AUTHOR]

(1) Background: Chayote [Sechium edule Jacq. (Sw.)] is a non-traditional export product; recently, demand has increased due to its nutritional and functional properties. There is a wide diversity of varietal groups (VGs) within this species. Despite this, only virens levis and nigrum spinosum varieties are commercialized on a large scale, while the rest are underutilized and poorly studied, so the genetic pool of this species is at risk. (2) Methods: The following variables were evaluated in the fruits of 10 chayote groups of varieties: shape, size, weight, stomatal frequency (SF), stoma size, stomatal index (SI), color index (CO*), pigments, titratable acidity (TA), total soluble solids (TSS), total sugars and moisture content. In addition, the postharvest behavior of the ten VGs stored at room temperature and the effect of 1-MCP on fruit quality during cold storage were evaluated. (3) Results: The groups a. minor and n. minor showed rapid weight loss, the albus varieties showed high epidermis oxidation, while v. levis, n. maximum, n. spinosum and n. xalapensis were susceptible to viviparity, blisters and fungal incidence. 1-MCP prevented chilling injury (CI) and weight loss. (4) Conclusions: The diversity of postharvest characteristics allows the use of VGs for different uses such as a fresh fruit, agroindustrial transformation or mixing with other vegetables. [ABSTRACT FROM AUTHOR]

Arboviruses transmitted by mosquitoes, including Japanese encephalitis virus (JEV), present a substantial global health threat. JEV is transmitted by mosquitoes in the genus Culex, which are common in both urban and rural areas in Vietnam. In 2020, we conducted a 1-year survey of Culex mosquito abundance in urban, suburban, and peri-urban areas of Hanoi using CDC-light traps. Mosquitoes were identified to species and sorted into pools based on species, sex, and trap location. The mosquito pools were also investigated by RT-qPCR for detection of JEV. In total, 4829 mosquitoes were collected over a total of 455 trap-nights, across 13 months. Collected mosquitoes included Culex, Aedes, Anopheles, and Mansonia species. Culex mosquitoes, primarily Cx. quinquefasciatus, predominated, especially in peri-urban areas. Most Culex mosquitoes were caught in the early months of the year. The distribution and abundance of mosquitoes exhibited variations across urban, suburban, and peri-urban sites, emphasizing the influence of environmental factors such as degree of urbanization, temperature and humidity on Culex abundance. No JEV was detected in the mosquito pools. This study establishes baseline knowledge of Culex abundance and temporal variation, which is crucial for understanding the potential for JEV transmission in Hanoi. [ABSTRACT FROM AUTHOR]

While the succession of terrestrial plant communities is well studied, less is known about succession on dead wood, especially how it is affected by environmental factors. While temperate forests face increasing canopy mortality, which causes considerable changes in microclimates, it remains unclear how canopy openness affects fungal succession. Here, we used a large real-world experiment to study the effect of closed and opened canopy on treatment-based alpha and beta fungal fruiting diversity. We found increasing diversity in early and decreasing diversity at later stages of succession under both canopies, with a stronger decrease under open canopies. However, the slopes of the diversity versus time relationships did not differ significantly between canopy treatments. The community dissimilarity remained mainly stable between canopies at ca. 25% of species exclusively associated with either canopy treatment. Species exclusive in either canopy treatment showed very low number of occupied objects compared to species occurring in both treatments. Our study showed that canopy loss subtly affected fungal fruiting succession on dead wood, suggesting that most species in the local species pool are specialized or can tolerate variable conditions. Our study indicates that the fruiting of the fungal community on dead wood is resilient against the predicted increase in canopy loss in temperate forests. [ABSTRACT FROM AUTHOR]

Invasive alien species are an important component of global change, threatening biodiversity, ecosystem functioning, economy, and human health. The number of alien species that attain the invasive status has experienced an exponential increase in recent years, leading some government agencies and stakeholders to allocate substantial resources to early detection, control, mitigation, and eradication programs. To develop effective nature conservation strategies, it is crucial to understand the invasive status of alien species and to identify priority species for management at spatial scales with a biogeographical basis. Despite significant progress in producing lists of alien species at the country level, a standard methodology for species assessment within ecological regions (i.e., regions with similar environmental or biogeographical characteristics) is still lacking. Here, we develop a systematic approach to determine invasion status and to prioritize invasive alien plant species within an ecoregion. We apply this approach in the Cantabrian Mixed Forests ecoregion, which encompasses biogeographically related areas from N Portugal, NW Spain, and SW France, and is strongly affected by plant invasions. By combining scientific evidence with expert opinion on the ecological characteristics of alien plants, we identified 175 invasive plant species in the study ecoregion, of which 37 cause massive environmental and/or socio-economic impacts. For each species, we provide comprehensive information and recommendations for scientists, land managers, policy makers, and other stakeholders under a biogeographical basis. This information includes species characteristics, invasion status/level, population trends, geographic locations and range size, local abundance, environmental and socio-economic impacts, and invaded habitats. We also accounted for administrative divisions within the ecoregion to facilitate the use of such evaluations in local-scale management and conservation plans. Our framework may be applied to any ecoregion worldwide, enhancing the assessment and management of invasive species pools within biogeographically meaningful regions. [ABSTRACT FROM AUTHOR]

Questions: Marine rocky outcrops are model systems of community assembly under harsh conditions. The prevailing environmental conditions that determine a coast–inland gradient of stress and disturbance impose a strong environmental filter on community assembly. However, the Atlantic rocky outcrops of Uruguay challenge this assumption as they exhibit high plant diversity at small spatial scales. We investigated this study system to answer: (1) which environmental factors determine diversity at the local scale; (2) and how does the regional pool influence species composition along the coast–inland gradient? Methods: We analyzed the local and regional determinants of plant community assembly in four rocky sites along the Uruguayan coast. Through a random sampling approach stratified by distance to the coast, we recorded species occurrences and microenvironmental conditions. Observed taxa were assigned into different species assemblages according to their typical vegetation type. Generalized Linear Model (GLM)–Poisson regression, quantile regressions and hierarchical cluster analyses were used to identify the factors underlying local richness and the spatial vegetation structure. Results: Nine different vegetation types generate a mass effect that enhances local diversity. Unexpectedly, 56% of the species are from non‐marine environments — e.g. grasslands or hydrophilous herblands. Species assemblages were spatially clustered, with a turnover of these clusters along the coast–inland gradient. Elevation, distance to the coast and vegetation cover promoted richness, likely due to an attenuation of marine filters. Meanwhile, substrate availability reduced richness, likely due to competitive exclusion as a result of more resources and homogeneous microenvironmental conditions. Conclusions: The high local diversity along the marine rocky outcrops of Uruguay is best explained by a functionally diverse regional species pool, which interacts with local heterogeneity, and by conditions that enhance or attenuate the effect of marine stress. Effective conservation and management strategies are key to minimize the detrimental effects of urbanization, fragmentation, and non‐native plant invasions on these diverse habitats. [ABSTRACT FROM AUTHOR]

In Cameroon, Aedes mosquitoes transmit various arboviruses, posing significant health risks. We aimed to characterize the Aedes virome in southwestern Cameroon and identify potential core viruses which might be associated with vector competence. A total of 398 Aedes mosquitoes were collected from four locations (Bafoussam, Buea, Edea, and Yaounde). Aedes albopictus dominated all sites except for Bafoussam, where Aedes africanus prevailed. Metagenomic analyses of the mosquitoes grouped per species into 54 pools revealed notable differences in the eukaryotic viromes between Ae. africanus and Ae. albopictus, with the former exhibiting greater richness and diversity. Thirty-seven eukaryotic virus species from 16 families were identified, including six novel viruses with near complete genome sequences. Seven viruses were further quantified in individual mosquitoes via qRT-PCR. Although none of them could be identified as core viruses, Guangzhou sobemo-like virus and Bafoussam mosquito solemovirus, were highly prevalent regionally in Ae. albopictus and Ae. africanus, respectively. This study highlights the diverse eukaryotic virome of Aedes species in southwestern Cameroon. Despite their shared genus, Aedes species exhibit limited viral sharing, with varying viral abundance and prevalence across locations. Ae. africanus, an understudied vector, harbors a rich and diverse virome, suggesting potential implications for arbovirus vector competence. [ABSTRACT FROM AUTHOR]

One of the key goals of ecology is to understand how communities are assembled. The species co‐existence theory suggests that community β‐diversity is influenced by species pool and community assembly processes, such as environmental filtering, dispersal events, ecological drift and biotic interactions. However, it remains unclear whether there are similar β‐diversity patterns among different soil microbial groups and whether all these mechanisms play significant roles in mediating β‐diversity patterns. By conducting a broad survey across Chinese deserts, we aimed to address these questions by investing biological soil crusts (biocrusts). Through amplicon‐sequencing, we acquired β‐diversity data for multiple microbial groups, that is, soil total bacteria, diazotrophs, phoD‐harbouring taxa, and fungi. Our results have shown varying distance decay rates of β‐diversity across microbial groups, with soil total bacteria showing a weaker distance‐decay relationship than other groups. The impact of the species pool on community β‐diversity varied across microbial groups, with soil total bacteria and diazotrophs being significantly influenced. While the contributions of specific assembly processes to community β‐diversity patterns varied among different microbial groups, significant effects of local community assembly processes on β‐diversity patterns were consistently observed across all groups. Homogenous selection and dispersal limitation emerged as crucial processes for all groups. Precipitation and soil C:P were the key factors mediating β‐diversity for all groups. This study has substantially advanced our understanding of how the communities of multiple microbial groups are structured in desert biocrust systems. [ABSTRACT FROM AUTHOR]

Nonstructural carbohydrates (NSC) are essential for tree growth and adaptation, yet our understanding of the seasonal storage and mobilization dynamics of whole-tree NSC is still limited, especially when tree functional types are involved. Here, Quercus acutissima Carruth. and Pinus massoniana Lamb, with distinct life-history traits (i.e. a deciduous broadleaf species vs an evergreen coniferous species), were studied to assess the size and seasonal fluctuations of organ and whole-tree NSC pools with a focus on comparing differences in carbon resource mobilization patterns between the two species. We sampled the organs (leaf, branch, stem and root) of the target trees repeatedly over four seasons of the year. Then, NSC concentrations in each organ were paired with biomass estimates from the allometric model to generate whole-tree NSC pools. The seasonal dynamics of the whole-tree NSC of Q. acutissima and P. massoniana reached the peak in autumn and summer, respectively. The starch pools of the two species were supplemented in the growing season while the soluble sugar pools were the largest in the dormant season. Seasonal dynamics of organ-level NSC concentrations and pools were affected by organ type and tree species, with above-ground organs generally increasing during the growing season and P. massoniana roots decreasing during the growing season. In addition, the whole-tree NSC pools of P. massoniana were larger but Q. acutissima showed larger seasonal fluctuations, indicating that larger storage was not associated with more pronounced seasonal fluctuations. We also found that the branch and root were the most dynamic organs of Q. acutissima and P. massoniana , respectively, and were the major suppliers of NSC to support tree growth activities. These results provide fundamental insights into the dynamics and mobilization patterns of NSC at the whole-tree level, and have important implications for investigating environmental adaptions of different tree functional types. [ABSTRACT FROM AUTHOR]

Studies of community assembly typically focus on the effects of abiotic environmental filters and stabilizing competition on functional trait dispersion within single trophic levels. Predation is a well‐known driver of community diversity and composition, yet the role of functionally diverse predator communities in filtering prey community traits has received less attention. We examined functionally diverse communities of predators (fishes) and prey (epifaunal crustaceans) in eelgrass (Zostera marina) beds in two northern California estuaries to evaluate the filtering effects of predator traits on community assembly and how filters acting on predators influence their ability to mediate prey community assembly. Fish traits related to bottom orientation were correlated with more clustered epifauna communities, and epifauna were generally overdispersed while fishes were clustered, suggesting prey may be pushed to disparate areas of trait space to avoid capture by benthic sit‐and‐wait predators. We also found correlations between the trait dispersions of predator and prey communities that strengthened after accounting for the effects of habitat filters on predator dispersion, suggesting that habitat filtering effects on predator species pools may hinder their ability to affect prey community assembly. Our results present compelling observational evidence that specific predator traits have measurable impacts on the community assembly of prey, inviting experimental tests of predator trait means on community assembly and explicit comparisons of how the relative effects of habitat filters and intraguild competition on predators impact their ability to affect prey community assembly. Integrating our understanding of traits at multiple trophic levels can help us better predict the impacts of community composition on food web dynamics as regional species pools shift with climate change and anthropogenic introductions. [ABSTRACT FROM AUTHOR]

Water turbidity alters prey detectability and prey selection by a predator. In dimorphic mesopredators, the effect of water turbidity on foraging success may be sex specific, primarily due to sex differences in reproductive allotment, body size and vulnerability to predation. To experimentally test the effect of turbidity on prey consumption with respect to sex, we used turquoise killifish (Nothobranchius furzeri), a small fish from ephemeral savanna pools in southeast Africa that vary widely in turbidity. Large males possess conspicuous nuptial coloration while females are smaller and drab. Vision is assumed to be a fundamental sense for turquoise killifish, despite often living in very turbid water. As mesopredators, killifish regulate the invertebrate community in ephemeral pools. We tested the consumption of bloodworms (benthic and red‐coloured) and glassworms (pelagic and transparent) under clear (<1NTU) and turbid (320 NTU) water conditions. We found that turquoise killifish maintained their overall foraging success irrespective of turbidity. In both the clear and turbid water, the females consumed three times more food than males relative to their body mass. This likely stems from the females' high nutritional demands due to daily reproduction. It also suggests that females are not risk‐aversive in clear water despite their smaller size. Water turbidity affected the type of prey consumed by turquoise killifish and demonstrated its potential to affect the community structure of invertebrate species in ephemeral pools. [ABSTRACT FROM AUTHOR]

What drives the composition of invaded communities and the local abundance of introduced species are key questions in ecology.Community‐assembly theory provides a useful framework for addressing these questions. Specifically, the environmental filtering model of community assembly predicts that a species' presence and abundance in a community depend on the interaction between its functional traits and the local environmental filters. However, for introduced species, larger‐scale dispersal and introduction‐related filters may restrict their regional trait pool.Here, we tested this framework using long‐term data from 50+ years of old‐field vegetation succession. We asked whether native and introduced plant assemblages followed the same trait‐based assembly rules. We also asked whether local functional dissimilarities between the two can be explained by regional species pool differences, a possibility that has rarely been addressed.We found strong similarities in the assembly processes of native and introduced plants. Average height and seed mass of both groups increased over time, consistent with previous studies of old‐field succession. Moreover, the two showed similar trait–abundance relationships. While there were also some differences, particularly in their trait–incidence relationships, these differences appeared to be minor.Furthermore, we identified species pool constraints on introduced species and found that the exotic species pool was biased towards early successional traits.Lastly, we found that highly invasive exotic species were also likely to deviate from the expected trait–abundance relationship, suggesting a link between the two.These results imply that introduced species generally follow the same assembly rules as native species. They also indicate that species pool differences can result in local functional composition differences, even when the two groups follow the same assembly rules. Moreover, there may be a link between species invasiveness and deviation from assembly rules, which, if further confirmed, provides a potential method of identifying strong invaders.Synthesis: Using data from a long‐term succession study, we showed several similarities, and some differences, in the assembly of native and introduced species assemblages. Our results provide a better understanding of the factors constraining and allowing invasion, and help in the identification of 'rule breaking' invaders. [ABSTRACT FROM AUTHOR]

Two water frog species: the pool frog Pelophylax lessonae (L) and the marsh frog P. ridibundus (R) occur sympatrically in Central Europe and form mixed populations (genetic systems) with their hybrid, the edible frog P. esculentus (E). The aim of the study was to assess the species composition of water frogs in urban and rural populations and compare our current findings with the results of previous studies. We surveyed the same sites that were investigated by Berger et al. in 1962–1970 (Poznań, urban landscape) and 1977–1997 (Dezydery Chłapowski Landscape Park, rural landscape). Because some ponds surveyed in the past were destroyed or dried-up, we also explored others located in the adjacent areas. We captured frogs during breeding seasons 2020 and 2021 and identified them by the nuclear marker gene SAI-1. We found three types of populations in the urban area: R-E, E-E and R-E-L and four in the rural area: R-E, L-E, E-E and R-E-L. Compared to the historical data, we found a drastic decrease in the frequency of P. lessonae in urban and rural landscapes: from 89.1% and 68% to 2.7% and 1.8%, respectively. At the same time, the frequency of P. ridibundus increased from 2.2% and 0.1% to 40% and 29.6%, respectively. A similar pattern was found for P. esculentus whose frequency increased from 8.7% and 31.9% to 57.3% and 68.6%, respectively. Additionally, we confirmed the presence of a cryptogenic Balkan water frog, P. kurtmuelleri, which was recently discovered in south-western Poland. The frequency of SAI-1 allele specific for this taxon reached 7.3%. The patterns found in both types of landscapes are in line with the current situation of both parental species in Europe. Such dynamic changes show the need for long-term monitoring of the population compositions of water frogs, what is crucial for their conservation management. [ABSTRACT FROM AUTHOR]

In response to non‐native plant invasions, many governments have established noxious weed lists to control and eradicate introduced invasive plants. However, invasive agronomic species are often unregulated, and the extent of their invasion across habitat types has never been determined.Using vegetation surveys across 222 plots, we investigated the contribution of agronomic versus noxious non‐native species to the levels of invasion across seven habitat types in central Canada.Although agronomic non‐native species, such as Poa pratensis and Bromus inermis, only made up 21.3% of the non‐native species pool, they accounted for 43.6% of non‐native plant species frequency and 74.4% of relative non‐native plant cover. They were also disproportionately overrepresented compared with noxious non‐native species across all habitat types, except saline marshes.The overabundance of agronomic non‐native plants in central Canada is likely the legacy of cultivar breeding, intentional seeding of introduced forage species and a lack of incentive for the use of native species.Synthesis and applications: Decelerating the invasion by agronomic non‐native plants will require approaches beyond noxious weed lists and initiatives in research, policy and education. These tools can include incentives to use native seed material, for example, in reclamation and forage and turf production, to reduce propagule pressure from invasive agronomic non‐native plants. [ABSTRACT FROM AUTHOR]

Interspecific information flow is known to affect individual fitness, population dynamics and community assembly, but there has been less study of how species diversity affects information flow and thereby ecosystem functioning and services. We address this question by first examining differences among species in the sensitivity, accuracy, transmissibility, detectability and value of the cues and signals they produce, and in how they receive, store and use information derived from heterospecifics. We then review how interspecific information flow occurs in communities, involving a diversity of species and sensory modes, and how this flow can affect ecosystem‐level functions, such as decomposition, seed dispersal or algae removal on coral reefs. We highlight evidence that some keystone species are particularly critical as a source of information used by eavesdroppers, and so have a disproportionate effect on information flow. Such keystone species include community informants producing signals, particularly about predation risk, that influence other species' landscapes of fear, and aggregation initiators creating cues or signals about resources. We suggest that the presence of keystone species means that there will likely be a positive relationship in many communities between species diversity and information through a 'sampling effect', in which larger pools of species are more likely to include the keystone species by chance. We then consider whether the number and relative abundance of species, irrespective of the presence of keystone species, matter to interspecific information flow; on this issue, the theory is less developed, and the evidence scant and indirect. Higher diversity could increase the quantity or quality of information that is used by eavesdroppers because redundancy increases the reliability of information or because the species provide complementary information. Alternatively, there could be a lack of a relationship between species diversity and information if there is widespread information parasitism where users are not sources, or if information sourced from heterospecifics is of lower value than that gained personally or sourced from conspecifics. Recent research suggests that species diversity does have information‐modulated community and ecosystem consequences, especially in birds, such as the diversity of species at feeders increasing resource exploitation, or the number of imitated species increasing responses to vocal mimics. A first step for future research includes comprehensive observations of information flow among different taxa and habitats. Then studies should investigate whether species diversity influences the cumulative quality or quantity of information at the community level, and consequently ecosystem‐level processes. An applied objective is to conserve species in part for their value as sources of information for other species, including for humans. [ABSTRACT FROM AUTHOR]

Large-scale forest restoration projects significantly reduce the net rates of forest loss. However, as a key component of forest restoration, planted forests have failed to restore biodiversity. China has implemented a large-scale afforestation program, which includes pure planted forests in particular, leading to various changes in ecosystem processes. Despite this, a comprehensive analysis of understory vegetation diversity patterns in these pure planted forests is still lacking. This study aimed to analyze the data on understory vegetation diversity from three typical pure and natural forest ecosystems of Hunan ecological forests to reveal their diversity patterns. The results revealed no significant difference in the understory diversity index between natural and pure forest types, although natural forests had a bigger species pool. The Zipf–Mandelbrot model was a better fit for species abundance distribution. The fitted results suggested that both environmental filtering and neutral processes affected the species abundance distribution and pure understory communities during restoration succession. Natural forests had the most stable understory diversity structure, whereas pure Phyllostachys heterocycla (Carr.) Mitford forests had the least stable structure. Multivariate regression tree analysis identified indicator species for each community. The gradient boosting model indicated that isothermality and slope direction were the most important factors affecting diversity. The β-diversity analysis showed that community establishment in the four forest types was affected via different mechanisms. The findings of this study have significant implications for understanding the impact of afforestation on the mechanisms for maintaining diversity. [ABSTRACT FROM AUTHOR]

Key message: Nested plot designs with concentric plots with increasing radii and size threshold underestimate tree species richness with respect to full census sampling with no tree size restrictions. Regeneration emerged as the most relevant pool for tree species richness estimation. Context: Nested or concentric plot designs, where trees are sampled according to their size and position, are common in National Forest Inventories (NFI) to reduce the sampling effort. However, this could bias the estimation of tree diversity such as species richness. Aims: The main goal of this study is to quantify the effect of the nested plot designs with increasing radii and diameter at breast height threshold on the number of tree species as well as to provide values for mean tree species richness per plot at the forest-type level using the Spanish NFI. Methods: We compared tree species richness according to the Spanish NFI nested plot design (radii ranging from 5 to 25 m with increasing minimum threshold in dbh from 7.5 to 42.5 cm as well as the regeneration compartment) with the richness estimate based on a full census (without restrictions in the location or size) in the Spanish NFI 25 m radius plot. Results: Our results confirmed the underestimation of tree species richness (around 32.5%) when using the nested design. The species omitted in the nested design sampling are often subordinates, typically with small diameters. Regeneration emerged as the main pool for tree species richness estimation. This pattern holds across the main forest types, indicating that it is a generalized rather than regional or local phenomenon. Conclusion: We strongly recommend using full census data for assessing tree species richness whenever available, as relying solely on nested designs can significantly underestimate tree species richness. [ABSTRACT FROM AUTHOR]

Background: Studies on haemosporidian diversity, including origin of human malaria parasites, malaria's zoonotic dynamic, and regional biodiversity patterns, have used target gene approaches. However, current methods have a trade-off between scalability and data quality. Here, a long-read Next-Generation Sequencing protocol using PacBio HiFi is presented. The data processing is supported by a pipeline that uses machine-learning for analysing the reads. Methods: A set of primers was designed to target approximately 6 kb, almost the entire length of the haemosporidian mitochondrial genome. Amplicons from different samples were multiplexed in an SMRTbell® library preparation. A pipeline (HmtG-PacBio Pipeline) to process the reads is also provided; it integrates multiple sequence alignments, a machine-learning algorithm that uses modified variational autoencoders, and a clustering method to identify the mitochondrial haplotypes/species in a sample. Although 192 specimens could be studied simultaneously, a pilot experiment with 15 specimens is presented, including in silico experiments where multiple data combinations were tested. Results: The primers amplified various haemosporidian parasite genomes and yielded high-quality mt genome sequences. This new protocol allowed the detection and characterization of mixed infections and co-infections in the samples. The machine-learning approach converged into reproducible haplotypes with a low error rate, averaging 0.2% per read (minimum of 0.03% and maximum of 0.46%). The minimum recommended coverage per haplotype is 30X based on the detected error rates. The pipeline facilitates inspecting the data, including a local blast against a file of provided mitochondrial sequences that the researcher can customize. Conclusions: This is not a diagnostic approach but a high-throughput method to study haemosporidian sequence assemblages and perform genotyping by targeting the mitochondrial genome. Accordingly, the methodology allowed for examining specimens with multiple infections and co-infections of different haemosporidian parasites. The pipeline enables data quality assessment and comparison of the haplotypes obtained to those from previous studies. Although a single locus approach, whole mitochondrial data provide high-quality information to characterize species pools of haemosporidian parasites. [ABSTRACT FROM AUTHOR]

The nonrandom association between landscape characteristics and the dominant life history strategies observed in species pools is a typical pattern in nature. Here, we argue that these associations determine predictable changes in the relative importance of assembly mechanisms along broadscale geographic gradients (i.e., the geographic context of metacommunity dynamics). To demonstrate that, we employed simulation models in which groups of species with the same initial distribution of niche breadths and dispersal abilities interacted across a wide range of landscapes with contrasting characteristics. By assessing the traits of dominant species in the species pool in each landscape type, we determined how different landscape characteristics select for different life history strategies at the metacommunity level. We analyzed the simulated data using the same analytical approaches used in the study of empirical metacommunities to derive predictions about the causal relationships between landscape characteristics and dominant life histories in species pools, as well as their reciprocal influence on empirical inferences regarding the assembly process. We provide empirical support for these predictions by contrasting the assembly of moth metacommunities in a tropical versus a temperate mountainous landscape. Together, our model framework and empirical analyses demonstrate how the geographic context of metacommunities influences our understanding of community assembly across broadscale ecological gradients. [ABSTRACT FROM AUTHOR]

Dark diversity includes ecologically suitable species currently absent in a site, albeit theoretically able to arrive from the surrounding region. Various methods can estimate the likelihood that an absent species is in the dark diversity of a site. Recent developments in estimation of dark diversity have advanced the field, yet uncertainty on method selection might lead to confusion and misleading results. Here, we provide methodological guidance by reanalyzing a data set used in a recently published dark‐diversity study (Hostens et al. 2023; Journal of Vegetation Science 34: e13212). Using various approaches to estimate dark diversity, we discuss why their estimations differ, and examine which methods are more appropriate than others for the particular data set. In this study, the hypergeometric method based on species co‐occurrences outperformed the other considered methods (species distribution modelling, Beals index). Further, we show how estimations of dark diversity can be combined with a Bayesian framework to examine which characteristics of sites and species are related to their tendency to have higher dark‐diversity size (sites) than expected or to be more frequently in dark diversity (species). This paper hopefully enhances confidence in dark‐diversity methods, allowing progress in both ecological theory and biodiversity conservation. [ABSTRACT FROM AUTHOR]

Climatic variation at local scales can influence both exposure and sensitivity of organisms and thereby scale up to influence population persistence and community composition across broader geographic extents. Tropical forest canopies are more climatically dynamic than the understorey. Consequently, the niche space of forest canopies has higher overlap in thermal conditions along elevation gradients, which imposes less of a climatic barrier to arboreal species than their ground‐dwelling counterparts. We use ant communities of the Australian Wet Tropics to test the prediction that ground communities should have higher rates of species turnover over elevation compared to arboreal communities. We sampled ground and arboreal ants along elevation gradients at a bioregional scale that includes four mountain sub‐regions. We assessed community composition at three spatial resolutions (regional, elevation, vertical) and then calculated beta diversity (species turnover) over elevation for ground and arboreal communities using null modelling procedures to compare different sized species pools. Vertical niche affinity was a strong contributor to overall biogeographic patterns; indicated by a strong interaction between vertical niche and elevation in beta diversity models. On average, the ground community exhibited a pronounced elevational distance–decay pattern while the arboreal community showed no pattern. Mean species turnover was 36% higher in ground than arboreal communities. Our findings suggest that the vertical niche has a pronounced effect on biogeographic patterns which has important implications for understanding the role of local scale climate conditions in shaping communities and for potential responses to future climate change. [ABSTRACT FROM AUTHOR]