The geography of biodiversity change in marine and terrestrial assemblages

Temporal insights into ecological community: Advancing waterbird monitoring with dome camera and deep learning

Biodiversity monitoring is critical for conservation and management. However, efficient species monitoring is often hindered by the complexities of ecological dynamics and the constraints of conventional techniques. This study presents an automated observation system by integrating dome camera with cascade neural networks (CNNs) to map the dynamics of waterbird communities across a semi-enclosed wetland in Dianchi Lake, southwestern China, a well-known important bird habitat. The trained model achieved performance with a Top-1 accuracy of 96.83 %, a Top-5 accuracy of 99.55 %, an F1 score of 93.54 %, a recall rate of 93.38 % and precision of 93.44 %, demonstrating its reliability for precise and well-balanced classification performance. Automatic and manual monitoring performed simultaneously showed highly significant correlations for community abundance (R2 = 0.89, n = 68, p < 0.0001), underscoring the value of this system as a tool for waterbird communty monitoring. Analysis of the monitoring results showed significant differences in species richness (n = 595, p < 0.0001) and community abundance (n = 595, p < 0.05) between morning and afternoon sessions, suggesting the need to consider ecological community changes across different time scales when conducting biodiversity surveys. In 2023, the system identified 17 species of birds in 5 orders, 6 families. By analyzing the data obtained from this system, the community composition, diversity changes, the arrival and departure times of waterbirds were revealed. Enabling high-frequency, continuous, and long-term monitoring at a lower cost, this system provides a reliable, alternative tool for developing species conservation and habitat management strategies.

Marine biodiversity loss in Finnish coastal waters: Evidence and implications for management

Marine biodiversity loss poses significant ecological and socio-economic challenges. This paper examines how coastal biodiversity loss is expressed and outlines implications for management. Synthesizing scientific literature on biodiversity change in the well-studied Finnish coastal waters (Baltic Sea) as a case study, we show that biodiversity loss occurs throughout the area in virtually all biotopes and organism groups examined. Biodiversity loss was expressed in 43 different ways. The three most common forms of biodiversity loss-local disappearance of species and decrease in abundance and biomass-covered nearly half of the observations. For these, the most common underlying causes were eutrophication, climate change, and physical disturbance of the seabed. Overall, eutrophication and climate change were the most frequent ones among the 13 loss drivers identified. We emphasize that critical knowledge gaps must be bridged, and monitoring improved, but, importantly, resolute decisions for action are required for the recovery of coastal marine ecosystems.

Contrasting Population Trajectories of Temperate Reef Fishes and Invertebrates Following Seasonal and Multi-Decadal Temperature Change

Temperature perturbations from climate change affect ecosystems through short-term pulse events, such as heatwaves, and chronic long-term shifts. Temperate rocky reef ecosystems have been observed to show substantial ecological change as a result of short-term temperature fluctuations, but the longer-term impacts of temperature change remain poorly understood. Here, we investigate temperate reef fishes and mobile invertebrates along Tasmania's east coast, contrasting trends in species richness, abundance, and community structure across seasons within a year to those observed over three decades of warming. Fishes exhibited dynamic seasonal shifts, but interannual changes in richness and abundance balanced out over decades with limited overall net change. In contrast, invertebrate communities changed little seasonally but suffered significant long-term losses. Our study revealed short-term ecological changes driven by temperature to be incongruent with long-term shifts. Species responded in varying ways, depending on life history and ecology. Fishes apparently tracked short temperature pulses, while less mobile invertebrates, such as echinoderms and molluscs, tolerated short-term fluctuations but exhibited long-term decline. Multi-scale studies across a broad range of taxa are needed to clarify thermal responses. The most vulnerable taxa-those facing long-term thermal stress-may be overlooked through decisions based on short-term studies, risking major biodiversity loss.

The global human impact on biodiversity

Human activities drive a wide range of environmental pressures, including habitat change, pollution and climate change, resulting in unprecedented effects on biodiversity1,2. However, despite decades of research, generalizations on the dimensions and extent of human impacts on biodiversity remain ambiguous. Mixed views persist on the trajectory of biodiversity at the local scale3 and even more so on the biotic homogenization of biodiversity across space4,5. We compiled 2,133 publications covering 97,783 impacted and reference sites, creating an unparallelled dataset of 3,667 independent comparisons of biodiversity impacts across all main organismal groups, habitats and the five most predominant human pressures1,6. For all comparisons, we quantified three key measures of biodiversity to assess how these human pressures drive homogenization and shifts in composition of biological communities across space and changes in local diversity, respectively. We show that human pressures distinctly shift community composition and decrease local diversity across terrestrial, freshwater and marine ecosystems. Yet, contrary to long-standing expectations, there is no clear general homogenization of communities. Critically, the direction and magnitude of biodiversity changes vary across pressures, organisms and scales at which they are studied. Our exhaustive global analysis reveals the general impact and key mediating factors of human pressures on biodiversity and can benchmark conservation strategies.

Plant diversity dynamics over space and time in a warming Arctic

The Arctic is warming four times faster than the global average1 and plant communities are responding through shifts in species abundance, composition and distribution2-4. However, the direction and magnitude of local changes in plant diversity in the Arctic have not been quantified. Using a compilation of 42,234 records of 490 vascular plant species from 2,174 plots across the Arctic, here we quantified temporal changes in species richness and composition through repeat surveys between 1981 and 2022. We also identified the geographical, climatic and biotic drivers behind these changes. We found greater species richness at lower latitudes and warmer sites, but no indication that, on average, species richness had changed directionally over time. However, species turnover was widespread, with 59% of plots gaining and/or losing species. Proportions of species gains and losses were greater where temperatures had increased the most. Shrub expansion, particularly of erect shrubs, was associated with greater species losses and decreasing species richness. Despite changes in plant composition, Arctic plant communities did not become more similar to each other, suggesting no biotic homogenization so far. Overall, Arctic plant communities changed in richness and composition in different directions, with temperature and plant-plant interactions emerging as the main drivers of change. Our findings demonstrate how climate and biotic drivers can act in concert to alter plant composition, which could precede future biodiversity changes that are likely to affect ecosystem function, wildlife habitats and the livelihoods of Arctic peoples5,6.

Divergent alpha and beta diversity trends of soil nematode fauna along gradients of environmental change in the Carpathian Ecoregion

There is a significant lack of research on how climate change influences long-term temporal trends in the biodiversity of soil organisms. Nematodes may be specifically adequate to test soil biodiversity changes, because they account for ~80% of all Metazoans and play key roles in the functioning of terrestrial ecosystems. Here, we report on the first synthesis study focused on temporal trends of nematode fauna over a period of 14 years (1986-1999) across the Carpathian Ecoregion. We provide new evidence that wetter conditions associated to global change contributes to driving nematode diversity at genus/family level. We observed opposite trends in soil nematode alpha diversity (increase) and beta diversity (decrease) consistent across ecosystem types and soil horizons, providing strong evidence for the influence of climate change on soil biodiversity at large spatial scales. An increase in the community functional uniformity along with a decline in beta diversity indicated more homogenous soil conditions over time. The Soil Stability Index (metric devised to assess soil homeostasis based on the functional composition of nematode communities) increased over time, indicating a decline of soil disturbances and more complex soil food webs. Our results highlight the importance of nematodes as powerful indicators of soil biodiversity trends affected by multiple facets of environmental change in long-term soil monitoring.

Management actions based on vehicle rides support threatened species of multiple taxa in open-habitat biodiversity hotspots - Abandoned military training areas

Abandoned military training areas are recognized as biodiversity hotspots. Here, threatened species benefit from low nutrient levels and a heterogeneous habitat mosaic that includes early successional stages created by military training activities. However, after abandonment, these areas are encroached by forest, and their conservation value may be lost without active management. Management can be approached in various ways, and it is important to determine which strategies are most beneficial for biodiversity. Here, we conducted a large-scale survey of vascular plants, grasshoppers, butterflies, and birds in more than 40 abandoned military training areas across Czechia, a country in Central Europe. We tested the responses of each taxon, as well as multitaxonomic diversity, to six management types: woody plant cutting, mowing for agriculture, mowing for conservation, grazing for agriculture, grazing for conservation, and vehicle rides. After accounting for spatial autocorrelation, we found that vehicle rides were the only management type positively related to the multitaxonomic diversity of threatened species. Additionally, it supported the abundance of threatened birds and the total species richness of grasshoppers. Although other management options also showed conservation benefits for some taxa (e.g., woody plant cutting for threatened grasshoppers), none had such a broad positive impact across taxa, and some had opposing effects (e.g., grazing for conservation benefited threatened butterflies but negatively affected threatened grasshoppers). While management decisions must always be tailored to local goals and conditions, we propose vehicle rides as a promising tool for managing biodiversity-rich areas where threatened species depend on early successional stages.

Climate shapes the spatial pattern in local β-diversity of alpine grasslands on the Tibetan Plateau

Little is known about the structure of plant communities across the vast Tibetan Plateau, which supports at least 12,000 species of alpine vascular plants including over 2000 endemics. We recorded species abundance in 485 sites stretching across 6000 km of the plateau. At each site, species abundance was measured in three quadrats that were 40 m apart, allowing us to quantify local β-diversity within the site. We found that local β-diversity in alpine meadows and steppes was significantly higher than expected by chance, indicating intraspecific aggregation within the sites. After controlling for random sampling effects, the magnitude of local β-diversity varied across the plateau: there was a positive relationship from west to east corresponding to increased rainfall; there were hump-shaped relationships with elevation and latitude. These patterns were driven mainly by regional variation in climate, but also by local soil properties and grazing regimes (our structural equation models (SEMs) explained 27 % and 26 % of variation in alpine meadows and steppes, respectively). Unexpectedly, precipitation-related variables were the strongest predictors in cold-wet alpine meadows while temperature-related variables were the strongest predictors in dry-warm alpine steppes. Our findings support the hypothesis that environmental filtering is largely responsible for local β-diversity of alpine grasslands across the Tibetan Plateau. We discuss how these findings inform efforts to conserve fragile alpine ecosystems threatened by rapid climate warming and overgrazing.

Emergent Relationships Between the Functional Diversity of Marine Planktonic Copepods and Ecosystem Functioning in the Global Ocean

Copepods are a major group of the mesozooplankton and thus a key part of marine ecosystems worldwide. Their fitness and life strategies are determined by their functional traits which allow different species to exploit various ecological niches. The range of functional traits expressed in a community defines its functional diversity (FD), which can be used to investigate how communities utilize resources and shape ecosystem processes. However, the spatial patterns of copepod FD and their relation to ecosystem functioning remain poorly understood on a global scale. Here, we use estimates of copepod community composition derived from species distribution models in combination with functional traits and indicators of ecosystem functioning to investigate the distribution of multiple facets of copepod FD, their relationships with species richness and ecosystem processes. We also project how anthropogenic climate change will impact the facets of copepod FD. We find that the facets of FD respond to species richness with variable strength and directions: functional richness, divergence, and dispersion increase with species richness whereas functional evenness and trait dissimilarity decrease. We find that primary production, mesozooplankton biomass and carbon export efficiency decrease with species richness, functional richness, divergence and dispersion. This suggests that ecosystem functioning may be disproportionally influenced by the traits of a few dominant species in line with the mass ratio hypothesis. Furthermore, climate change is projected to promote trait homogenization globally, which may decrease mesozooplankton biomass and carbon export efficiency globally. The emergent covariance patterns between copepod FD and ecosystem functions we find here strongly call for better integrating FD measurements into field studies and across scales to understand the effects of changing zooplankton biodiversity on marine ecosystem functioning.

Warming and cooling catalyse widespread temporal turnover in biodiversity

Turnover in species composition through time is a dominant form of biodiversity change, which has profound effects on the functioning of ecological communities1-4. Turnover rates differ markedly among communities4, but the drivers of this variation across taxa and realms remain unknown. Here we analyse 42,225 time series of species composition from marine, terrestrial and freshwater assemblages, and show that temporal rates of turnover were consistently faster in locations that experienced faster temperature change, including both warming and cooling. In addition, assemblages with limited access to microclimate refugia or that faced stronger human impacts on land were especially responsive to temperature change, with up to 48% of species replaced per decade. These results reveal a widespread signal of vulnerability to continuing climate change and highlight which ecological communities are most sensitive, raising concerns about ecosystem integrity as climate change and other human impacts accelerate.

Changes in Plant Biomass Are Driven by Persisting Plant Species, but Species Gains Drive Nematode Carbon Dynamics

Global change drivers, such as shrub encroachment, alter above- and belowground communities, and the consequences of these changes for ecosystem functioning are largely unknown. We used the modified Price equation to quantify how the presence of shrubs alters the richness, composition, and abundance of plant and nematode communities and the resulting effects on ecosystem functioning (i.e., plant biomass and nematode carbon [C] metabolism) on the Qinghai-Tibet Plateau. Plots with shrubs had increased plant biomass (mostly due to persisting plant species producing more biomass) and nematode C metabolism (mostly due to increases in nematode species richness). The strength of the species richness effect on plant biomass was positively associated with the strength of the species richness on nematode C metabolism. Increases in the biomass of persisting species and species gains promote plant biomass and nematode C metabolism, respectively, which may accelerate decomposition and C turnover on the Qinghai-Tibet Plateau.

CooccurrenceAffinity: An R package for computing a novel metric of affinity in co-occurrence data that corrects for pervasive errors in traditional indices

1. Analysis of co-occurrence data with traditional indices has led to many problems such as sensitivity of the indices to prevalence and the same value representing either a strong positive or strong negative association across different datasets. In our recent study (Mainali et al 2022), we revealed the source of the problems that make the traditional indices fundamentally flawed and unreliable-namely that the indices in common use have no target of estimation quantifying degree of association in the non-null case-and we further developed a novel parameter of association, alpha, with complete formulation of the null distribution for estimating the mechanism of affinity. We also developed the maximum likelihood estimate (MLE) of alpha in our previous study. 2. Here, we introduce the CooccurrenceAffinity R package that computes the MLE for alpha. We provide functions to perform the analysis based on a 2×2 contingency table of occurrence/co-occurrence counts as well as a m×n presence-absence matrix (e.g., species by site matrix). The flexibility of the function allows a user to compute the alpha MLE for entity pairs on matrix columns based on presence-absence states recorded in the matrix rows, or for entity pairs on matrix rows based on presence-absence recorded in columns. We also provide functions for plotting the computed indices. 3. As novel components of this software paper not reported in the original study, we present theoretical discussion of a median interval and of four types of confidence intervals. We further develop functions (a) to compute those intervals, (b) to evaluate their true coverage probability of enclosing the population parameter, and (c) to generate figures. 4. CooccurrenceAffinity is a practical and efficient R package with user-friendly functions for end-to-end analysis and plotting of co-occurrence data in various formats, making it possible to compute the recently developed metric of alpha MLE as well as its median and confidence intervals introduced in this paper. The package supplements its main output of the novel metric of association with the three most common traditional indices of association in co-occurrence data: Jaccard, Sørensen-Dice, and Simpson.

Potential plant extinctions with the loss of the Pleistocene mammoth steppe

During the Pleistocene-Holocene transition, the dominant mammoth steppe ecosystem across northern Eurasia vanished, in parallel with megafauna extinctions. However, plant extinction patterns are rarely detected due to lack of identifiable fossil records. Here, we introduce a method for detection of plant taxa loss at regional (extirpation) to potentially global scale (extinction) and their causes, as determined from ancient plant DNA metabarcoding in sediment cores (sedaDNA) from lakes in Siberia and Alaska over the past 28,000 years. Overall, potential plant extinctions track changes in temperature, in vegetation, and in megafauna extinctions at the Pleistocene-Holocene transition. Estimated potential plant extinction rates were 1.7-5.9 extinctions per million species years (E/MSY), above background extinction rates but below modern estimates. Major potential plant extinction events were detected around 17,000 and 9000 years ago which lag maximum vegetation turnover. Our results indicate that herbaceous taxa and taxa contributing less to beta diversity are more vulnerable to extinction. While the robustness of the estimates will increase as DNA reference libraries and ancient sedaDNA data expand, the available data support that plants are more resilient to environmental changes than mammals.

Emergent patterns of reef fish diversity correlate with coral assemblage shifts along the Great Barrier Reef

Escalating climate and anthropogenic disturbances draw into question how stable large-scale patterns in biological diversity are in the Anthropocene. Here, we analyse how patterns of reef fish diversity have changed from 1995 to 2022 by examining local diversity and species dissimilarity along a large latitudinal gradient of the Great Barrier Reef and to what extent this correlates with changes in coral cover and coral composition. We find that reef fish species richness followed the expected latitudinal diversity pattern (i.e., greater species richness toward lower latitudes), yet has undergone significant change across space and time. We find declines in species richness at lower latitudes in recent periods but high variability at higher latitudes. Reef fish turnover continuously increased over time at all latitudes and did not show evidence of a return. Altered diversity patterns are characterised by heterogeneous changes in reef fish trophic groups across the latitudinal gradient. Shifts in coral composition correlate more strongly with reef fish diversity changes than fluctuations in coral cover. Our findings provide insight into the extent to which classic macroecological patterns are maintained in the Anthropocene, ultimately questioning whether these patterns are decoupling from their original underlying drivers.

The Anthropocene and the biodiversity crisis: an eco-evolutionary perspective

A major facet of the Anthropocene is global change, such as climate change, caused by human activities, which drastically affect biodiversity with all-scale declines and homogenization of biotas. This crisis does not only affect the ecological dynamics of biodiversity, but also its evolutionary dynamics, including genetic diversity, an aspect that is generally neglected. My tenet is therefore to consider biodiversity dynamics from an eco-evolutionary perspective, i.e. explicitly accounting for the possibility of rapid evolution and its feedback on ecological processes and the environment. I represent the impact of the various avatars of global change in a temporal perspective, from pre-industrial time to the near future, allowing to visualize their dynamics and to set desired values that should not be trespassed for a given time (e.g., +2 °C for 50 years from now). After presenting the impact of various stressors (e.g., climate change) on biodiversity, this representation is used to heuristically show the relevance of an eco-evolutionary perspective: (i) to analyze how biodiversity will respond to the stressors, for example by seeking out more suitable conditions or adapting to new conditions; (ii) to serve in predictive exercises to envision future dynamics (decades to centuries) under stressor impact; (iii) to propose nature-based solutions to the crisis. Significant obstacles stand in the way of the development of such an approach, in particular the general lack of interest in intraspecific diversity, and perhaps more generally a lack of understanding that, we, humans, are only a modest part of biodiversity.

Overcoming Shifting Baselines: Paleo-Behaviour Reveals Industrial Revolution as Tipping Point

Human activities have significantly altered coastal ecosystems worldwide. The phenomenon of shifting baselines syndrome (SBS) complicates our understanding of these changes, masking the true scale of human impacts. This study investigates the long-term ecological effects of anthropogenic activities on New Zealand's coastal ecosystems over 800 years using fish otolith microchemical profiling and dynamic time warping across an entire stock unit. Results reveal a shift in snapper (Chrysophrys auratus; Sparidae) habitat-use behaviour, transitioning from low-salinity estuarine environments to higher-salinity habitats, correlating with ongoing land-use changes. This shift coincided with New Zealand's localised Industrial Revolution, which served as a tipping point for widespread ecosystem transformation. By comparing current coastal fish movement profiles with historical baselines, we provide evidence to address SBS and guide conservation strategies. Re-establishing pre-industrial habitat-use behaviours in snapper will indicate successful habitat restoration, promoting overall ecosystem connectivity and resilience. Our findings enable more effective habitat restoration measures and sustainable management practices, informing policies for maintaining coastal biodiversity and ecosystem function.

Half a Century of Temperate Non-Forest Vegetation Changes: No Net Loss in Species Richness, but Considerable Shifts in Taxonomic and Functional Composition

In recent decades, global change and local anthropogenic pressures have severely affected natural ecosystems and their biodiversity. Although disentangling the effects of these factors is difficult, they are reflected in changes in the functional composition of plant communities. We present a comprehensive, large-scale analysis of long-term changes in plant communities of various non-forest habitat types in the Czech Republic based on 1154 vegetation-plot time series from 53 resurvey studies comprising 3909 vegetation-plot records. We focused not only on taxonomic diversity but also on the functional characteristics of communities. Species richness of most habitat types increased over time, and taxonomic and functional community composition shifted significantly. Habitat specialists and threatened species became less represented in plant communities, indicating a decline in habitat quality. The spread of trees, shrubs, tall herbaceous plants, strong competitors, and nutrient-demanding species in all non-forest habitats, coupled with the decline of light-demanding species, suggests an effect of eutrophication and natural succession following the abandonment of traditional management. Moreover, we identified specific trends in certain habitats. In wetlands, springs, and mires, moisture-demanding species decreased, probably due to drainage, river regulations, and increasing drought resulting from climate change. Dry grasslands, ruderal, weed, sand, and shallow-soil vegetation became more mesic, and successional processes were most pronounced in these communities, suggesting a stronger effect of abandonment of traditional management and eutrophication. In alpine and subalpine vegetation, meadows and mesic pastures, and heathlands, insect-pollinated species declined, and the proportion of grasses increased. Overall, these functional changes provide deep insights into the underlying drivers and help conservationists take appropriate countermeasures.

Climate change drives fish communities: Changing multiple facets of fish biodiversity in the Northwest Pacific Ocean

Global marine biodiversity is experiencing significant alterations due to climate change. Incorporating phylogenetic and functional diversity may provide novel insights into these impacts. This study used an ensemble model approach (random forest and boosted regression tree), to predict the habitat distribution of 47 fish species in the Northwestern Pacific under contemporary (2000-2014) and future scenarios (2040-2050, 2090-2100). We first examined the relationship between eleven functional traits and habitat changes, predicting the spatial distribution of functional traits within fish communities. A significant correlation was observed between temperature preference and habitat changes, highlighting the vulnerability of cold-water species and potential advantages for warm-water species in the future. Moreover, fish communities exhibited a spatial gradient distribution with southern regions characterized by shorter-lived and earlier maturity, contrasting with longer-lived and later maturity species in the north. Secondly, to assess the impact of climate change on marine biodiversity, we explored the taxonomic, phylogenetic, and functional diversity under contemporary and future scenarios, revealing higher indices in the East China Sea (ECS) and the coastal sea of Japan, with the Taiwan Strait emerging as a contemporary biodiversity hotspot. In future scenarios, the three biodiversity indices would decline in the Yellow Sea and ECS, but increase in the sea beyond the continental shelf, coastal sea of Hokkaido, and Sea of Okhotsk. Lastly, we explored processes and mechanisms in the change of community composition. By quantifying β-diversity, we identified species loss (nestedness) as the primary driver of fish community change by 2040-2050, with species replacement (turnover) predicted to become dominant in the far future. Our results explore the potential changes in multiple facets of fish biodiversity, providing crucial insights for policymakers aiming to protect fish resources and biodiversity.

Habitat Stability Modulates Temporal β-Diversity Patterns of Seagrass-Associated Amphipods Across a Temperate-Subtropical Transition Zone

Identifying drivers that shape biodiversity across biogeographical regions is important to predict ecosystem responses to environmental changes. While β-diversity has been widely used to describe biodiversity patterns across space, the dynamic assembly of species over time has been comparatively overlooked. Insights from terrestrial and marine studies on temporal β-diversity has mostly considered environmental drivers, while the role of biotic mechanisms has been largely ignored. Here, we investigated patterns of temporal variation in β-diversity of seagrass-associated amphipods. We conducted a study in three biogeographical regions across a temperate to subtropical latitudinal gradient (approximately 2000 km, 13° of latitude in total). In each region, we randomly selected three Cymodocea nodosa meadows, totaling nine meadows sampled seasonally (i.e., four times per year) from 2016 to 2018. We partitioned temporal β-diversity into its turnover (i.e., species replacement) and nestedness (i.e., differences in species composition caused by species losses) components and addressed the relative influence of both temporal variation in habitat structure (i.e., biotic driver) and environmental conditions on the observed β-diversity patterns. Our study revealed high temporal β-diversity of amphipod assemblages across the three biogeographical regions, denoting significant fluctuations in species composition over time. We identified species turnover as the primary driver of temporal β-diversity, strongly linked to temporal variability in local habitat structure rather than to regional climatic drivers. Subtropical Atlantic meadows with high structural stability over time exhibited the largest turnover rates compared with temperate Mediterranean meadows, under lower structural stability, where nestedness was a more relevant component of temporal β-diversity. Our results highlight the crucial role of habitat stability in modulating temporal β-diversity patterns on animals associated with seagrasses, stressing the importance of monitoring variations in habitat structure over time for developing management plans and restoration actions in the context of diversity loss and fragmentation of ecosystems.

Soil community history strengthens belowground multitrophic functioning across plant diversity levels in a grassland experiment

Biodiversity experiments revealed that plant diversity loss can decrease ecosystem functions across trophic levels. To address why such biodiversity-function relationships strengthen over time, we established experimental mesocosms replicating a gradient in plant species richness across treatments of shared versus non-shared history of (1) the plant community and (2) the soil fauna community. After 4 months, we assessed the multitrophic functioning of soil fauna via biomass stocks and energy fluxes across the food webs. We find that soil community history significantly enhanced belowground multitrophic function via changes in biomass stocks and community-average body masses across the food webs. However, variation in plant diversity and plant community history had unclear effects. Our findings underscore the importance of long-term community assembly processes for soil fauna-driven ecosystem function, with species richness and short-term plant adaptations playing a minimal role. Disturbances that disrupt soil community stability may hinder fauna-driven ecosystem functions, while recovery may require several years.

A continental-wide decline of occupancy and diversity in five Neotropical carnivores

The Neotropics are a global biodiversity hotspot that has undergone dramatic land use changes over the last decades. However, a temporal perspective on the continental-wide distributions of species in this region is still missing. To unveil it, we model the entire area of occupancy of five Neotropical carnivore species at two time periods (2000-2013 and 2014-2021) using integrated species distribution models (ISDMs) in a Bayesian framework. The carnivores are the jaguarundi (Herpailurus yagouaroundi), margay (Leopardus wiedii), maned wolf (Chrysocyon brachyurus), tayra (Eira barbara), and giant otter (Pteronura brasiliensis). We mapped the temporal change, the areas where gains and losses accumulated for all species (hotspots of change) and calculated the temporal species turnover and change in spatial turnover. We show that (1) most carnivore species have declined their area of occupancy (i.e., range size) in the last two decades, (2) their diversity has decreased over time, mostly in the Chaco region, and (3) that hotspots of fast species composition turnover are in Chaco, the Caatinga region, and northwest of Mexico. We discuss how these newly identified hotspots of change overlap with regions of well-known and pronounced land use transformation. These estimated patterns of overall decline are alarming, more so given that four out of the five species had been classified as not threatened by IUCN. The official global threat status of these species may need to be re-evaluated. All this would be invisible if standard forecasts, local expert knowledge, or static threat criteria, such as range size, were used. We thus provide a new approach to evaluate past species range dynamics based on multiple lines of evidence, which can be employed over more species in the future, particularly in under-sampled regions.

Slower but deeper community change: Intrinsic dynamics regulate anthropogenic impacts on species temporal turnover

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.

Distinct impacts of microplastics on the carbon sequestration capacity of coastal blue carbon ecosystems: A case of seagrass beds

Seagrass beds, as an important coastal blue carbon ecosystem, are excellent at storing organic carbon and mitigating the impacts of global climate change. However, seagrass beds are under threat due to increased human activities and ubiquitous presence of microplastics (MPs) in marine environments. Bibliometric analysis shows that the distribution and accumulation of microplastics in seagrass beds has been widely documented worldwide, but their impacts on seagrass beds, particularly on carbon sequestration capacity, have not been given sufficient attention. This review aims to outline the potential impacts of MPs on the carbon sequestration capacity of seagrass ecosystems across five key aspects: (1) MPs act as sources of organic carbon, contributing to direct pollution in seagrass ecosystems; (2) Impacts of MPs on seagrasses and their epiphytic algae, affecting plant growth and net primary productivity; (3) Impacts of MPs on microorganisms, influencing production of recalcitrant dissolved organic carbon and greenhouse gas; (4) Impacts of MPs on seagrass sediments, altering the quality, structure, properties and decomposition processes of plant litters; (5) Other complex impacts on the seagrass ecosystems, depending on different behaviors of MPs. Latest progress in these fields are summarized and recommendations for future work are discussed. This review can provide valuable insights to facilitate future multidisciplinary investigations and encourage society-wide implementation of effective conservation measures to enhance the carbon sequestration capacity of seagrass beds.

Massive barnacle recruitment on the Gulf of St. Lawrence coast of Nova Scotia (Canada) in 2024 linked to increased sea surface temperature

With the ongoing climate and oceanographic change, an increasing number of studies are reporting dramatic population losses caused by thermal extremes in intertidal habitats. Under moderate warming, however, populations can fare better in places where species normally experienced suboptimal temperatures. This article reports the massive recruitment of the barnacle Semibalanus balanoides on the Gulf of St. Lawrence coast of Nova Scotia (Canada) in 2024. As recruits appear mostly during May in this region, coastal sea surface temperature (SST) in April is critical for the ecological performance of larvae, as they are pelagic and live in the water column for weeks before intertidal settlement. Thus, a study that spanned 12 years (2005 to 2016) on this coast found that annual barnacle recruitment was positively correlated to April SST. In April 2024, coastal SST was 116% higher than for the same month averaged over those 12 years (4.1 vs. 1.9 °C). This SST spike was followed by an elevated recruitment that was 111% higher than the average for those 12 years (1,278 vs. 607 recruits dm-2). Overall for the studied years, the amount of variation in annual barnacle recruitment statistically explained by April SST was 51%. While the southern distribution limit of S. balanoides has moved northwards in recent decades due to lethal warming, our results support the notion of improving reproductive success with seawater warming on colder northern shores.

Coping with collapse: Functional robustness of coral-reef fish network to simulated cascade extinction

Human activities and climate change have accelerated species losses and degradation of ecosystems to unprecedented levels. Both theoretical and empirical evidence suggest that extinction cascades contribute substantially to global species loss. The effects of extinction cascades can ripple across levels of ecological organization, causing not only the secondary loss of taxonomic diversity but also functional diversity erosion. Here, we take a step forward in coextinction analysis by estimating the functional robustness of reef fish communities to species loss. We built a tripartite network with nodes and links based on a model output predicting reef fish occupancy (113 species) as a function of coral and turf algae cover in Southwestern Atlantic reefs. This network comprised coral species, coral-associated fish (site occupancy directly related to coral cover), and co-occurring fish (occupancy indirectly related to coral cover). We used attack-tolerance curves and estimated network robustness (R) to quantify the cascading loss of reef fish taxonomic and functional diversity along three scenarios of coral species loss: degree centrality (removing first corals with more coral-associated fish), bleaching vulnerability and post-bleaching mortality (most vulnerable removed first), and random removal. Degree centrality produced the greatest losses (lowest R) in comparison with other scenarios. In this scenario, while functional diversity was robust to the direct loss of coral-associated fish (R = 0.85), the taxonomic diversity was not robust to coral loss (R = 0.54). Both taxonomic and functional diversity showed low robustness to indirect fish extinctions (R = 0.31 and R = 0.57, respectively). Projections of 100% coral species loss caused a reduction of 69% of the regional trait space area. The effects of coral loss in Southwestern Atlantic reefs went beyond the direct coral-fish relationships. Ever-growing human impacts on reef ecosystems can cause extinction cascades with detrimental consequences for fish assemblages that benefit from corals.

Biodiversity in changing environments: An external-driver internal-topology framework to guide intervention

Accompanying the climate crisis is the more enigmatic biodiversity crisis. Rapid reorganization of biodiversity due to global environmental change has defied prediction and tested the basic tenets of conservation and restoration. Conceptual and practical innovation is needed to support decision making in the face of these unprecedented shifts. Critical questions include: How can we generalize biodiversity change at the community level? When are systems able to reorganize and maintain integrity, and when does abiotic change result in collapse or restructuring? How does this understanding provide a template to guide when and how to intervene in conservation and restoration? To this end, we frame changes in community organization as the modulation of external abiotic drivers on the internal topology of species interactions, using plant-plant interactions in terrestrial communities as a starting point. We then explore how this framing can help translate available data on species abundance and trait distributions to corresponding decisions in management. Given the expectation that community response and reorganization are highly complex, the external-driver internal-topology (EDIT) framework offers a way to capture general patterns of biodiversity that can help guide resilience and adaptation in changing environments.

Temporal dynamics of climate change exposure and opportunities for global marine biodiversity

Climate change is exposing marine species to unsuitable temperatures while also creating new thermally suitable habitats of varying persistence. However, understanding how these different dynamics will unfold over time remains limited. We use yearly sea surface temperature projections to estimate temporal dynamics of thermal exposure (when temperature exceeds realised species' thermal limits) and opportunity (when temperature at a previously unsuitable site becomes suitable) for 21,696 marine species globally until 2100. Thermal opportunities are projected to arise earlier and accumulate gradually, especially in temperate and polar regions. Thermal exposure increases later and occurs more abruptly, mainly in the tropics. Assemblages tend to show either high exposure or high opportunity, but seldom both. Strong emissions reductions reduce exposure around 100-fold whereas reductions in opportunities are halved. Globally, opportunities are projected to emerge faster than exposure until mid-century when exposure increases more rapidly under a high emissions scenario. Moreover, across emissions and dispersal scenarios, 76%-97% of opportunities are projected to persist until 2100. These results indicate thermal opportunities could be a major source of marine biodiversity change, especially in the near- and mid-term. Our work provides a framework for predicting where and when thermal changes will occur to guide monitoring efforts.

Gaps and opportunities in modelling human influence on species distributions in the Anthropocene

Understanding species distributions is a global priority for mitigating environmental pressures from human activities. Ample studies have identified key environmental (climate and habitat) predictors and the spatial scales at which they influence species distributions. However, regarding human influence, such understandings are largely lacking. Here, to advance knowledge concerning human influence on species distributions, we systematically reviewed species distribution modelling (SDM) articles and assessed current modelling efforts. We searched 12,854 articles and found only 1,429 articles using human predictors within SDMs. Collectively, these studies of >58,000 species used 2,307 unique human predictors, suggesting that in contrast to environmental predictors, there is no 'rule of thumb' for human predictor selection in SDMs. The number of human predictors used across studies also varied (usually one to four per study). Moreover, nearly half the articles projecting to future climates held human predictors constant over time, risking false optimism about the effects of human activities compared with climate change. Advances in using human predictors in SDMs are paramount for accurately informing and advancing policy, conservation, management and ecology. We show considerable gaps in including human predictors to understand current and future species distributions in the Anthropocene, opening opportunities for new inquiries. We pose 15 questions to advance ecological theory, methods and real-world applications.

Projected loss of brown macroalgae and seagrasses with global environmental change

Although many studies predict extensive future biodiversity loss and redistribution in the terrestrial realm, future changes in marine biodiversity remain relatively unexplored. In this work, we model global shifts in one of the most important marine functional groups-ecosystem-structuring macrophytes-and predict substantial end-of-century change. By modelling the future distribution of 207 brown macroalgae and seagrass species at high temporal and spatial resolution under different climate-change projections, we estimate that by 2100, local macrophyte diversity will decline by 3-4% on average, with 17 to 22% of localities losing at least 10% of their macrophyte species. The current range of macrophytes will be eroded by 5-6%, and highly suitable macrophyte habitat will be substantially reduced globally (78-96%). Global macrophyte habitat will shift among marine regions, with a high potential for expansion in polar regions.

Three major steps toward the conservation of freshwater and riparian biodiversity

Freshwater ecosystems and their bordering wetlands and riparian zones are vital for human society and biological diversity. Yet, they are among the most degraded ecosystems, where sharp declines in biodiversity are driven by human activities, such as hydropower development, agriculture, forestry, and fisheries. Because freshwater ecosystems are characterized by strongly reciprocal linkages with surrounding landscapes, human activities that encroach on or degrade riparian zones ultimately lead to declines in freshwater-riparian ecosystem functioning. We synthesized results of a symposium on freshwater, riparian, and wetland processes and interactions and analyzed some of the major problems associated with improving freshwater and riparian research and management. Three distinct barriers are the lack of involvement of local people in conservation research and management, absence of adequate measurement of biodiversity in freshwater and riparian ecosystems, and separate legislation and policy on riparian and freshwater management. Based on our findings, we argue that freshwater and riparian research and conservation efforts should be integrated more explicitly. Best practices for overcoming the 3 major barriers to improved conservation include more and sustainable use of traditional and other forms of local ecological knowledge, choosing appropriate metrics for ecological research and monitoring of restoration efforts, and mirroring the close links between riparian and freshwater ecosystems in legislation and policy. Integrating these 3 angles in conservation science and practice will provide substantial benefits in addressing the freshwater biodiversity crisis.

Population abundance estimates in conservation and biodiversity research

Measuring and tracking biodiversity from local to global scales is challenging due to its multifaceted nature and the range of metrics used to describe spatial and temporal patterns. Abundance can be used to describe how a population changes across space and time, but it can be measured in different ways, with consequences for the interpretation and communication of spatiotemporal patterns. We differentiate between relative and absolute abundance, and discuss the advantages and disadvantages of each for biodiversity monitoring, conservation, and ecological research. We highlight when absolute abundance can be advantageous and should be prioritized in biodiversity monitoring and research, and conclude by providing avenues for future research directions to better assess the necessity of absolute abundance in biodiversity monitoring.

Unravelling the functional and phylogenetic dimensions of novel ecosystem assemblages

Human activities are causing taxonomic rearrangements across ecosystems that often result in the emergence of novel communities (assemblies with no historical representative). It is commonly assumed that these changes in the taxonomic makeup of ecosystems also inevitably lead to changes in other aspects of biodiversity, namely functional and phylogenetic diversity. However, this assumption is not always valid, as the changes in functional and phylogenetic composition resulting from taxonomic shifts depend on the level of redundancy in the evaluated community. Therefore, we need improved theoretical frameworks to predict when we can expect coordinated or decoupled responses among these three facets of biodiversity. To advance this understanding, we discuss the conceptual and methodological issues that complicate establishing a link between taxonomic rearrangements driven by human activities and the associated functional and phylogenetic changes. Here, we show that is crucial to consider the expected changes in functional and phylogenetic composition as communities are reshaped owing to human drivers of biodiversity loss to forecast the impacts of novel assemblages on ecosystem functions and the services they provide to humanity. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Towards a novel biosphere in 2300: rapid and extensive global and biome-wide climatic novelty in the Anthropocene

Recent climate change has effectively rewound the climate clock by approximately 120 000 years and is expected to reverse this clock a further 50 Myr by 2100. We aimed to answer two essential questions to better understand the changes in ecosystems worldwide owing to predicted climate change. Firstly, we identify the locations and time frames where novel ecosystems could emerge owing to climate change. Secondly, we aim to determine the extent to which biomes, in their current distribution, will experience an increase in climate-driven ecological novelty. To answer these questions, we analysed three perspectives on how climate changes could result in novel ecosystems in the near term (2100), medium (2200) and long term (2300). These perspectives included identifying areas where climate change could result in new climatic combinations, climate isoclines moving faster than species migration capacity and current environmental patterns being disaggregated. Using these metrics, we determined when and where novel ecosystems could emerge. Our analysis shows that unless rapid mitigation measures are taken, the coverage of novel ecosystems could be over 50% of the land surface by 2100 under all change scenarios. By 2300, the coverage of novel ecosystems could be above 80% of the land surface. At the biome scale, these changes could mean that over 50% of locations could shift towards novel ecosystems, with the majority seeing these changes in the next few decades. Our research shows that the impact of climate change on ecosystems is complex and varied, requiring global action to mitigate and adapt to these changes. This article is part of the theme issue 'Biodiversity dynamics and stewardship in a transforming biosphere'. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Navigating ecological novelty towards planetary stewardship: challenges and opportunities in biodiversity dynamics in a transforming biosphere

Human-induced global changes, including anthropogenic climate change, biotic globalization, trophic downgrading and pervasive land-use intensification, are transforming Earth's biosphere, placing biodiversity and ecosystems at the forefront of unprecedented challenges. The Anthropocene, characterized by the importance of Homo sapiens in shaping the Earth system, necessitates a re-evaluation of our understanding and stewardship of ecosystems. This theme issue delves into the multifaceted challenges posed by the ongoing ecological planetary transformation and explores potential solutions across four key subthemes. Firstly, it investigates the functioning and stewardship of emerging novel ecosystems, emphasizing the urgent need to comprehend the dynamics of ecosystems under uncharted conditions. The second subtheme focuses on biodiversity projections under global change, recognizing the necessity of predicting ecological shifts in the Anthropocene. Importantly, the inherent uncertainties and the complexity of ecological responses to environmental stressors pose challenges for societal responses and for accurate projections of ecological change. The RAD framework (resist-accept-direct) is highlighted as a flexible yet nuanced decision-making tool that recognizes the need for adaptive approaches, providing insights for directing and adapting to Anthropocene dynamics while minimizing negative impacts. The imperative to extend our temporal perspective beyond 2100 is emphasized, given the irreversible changes already set in motion. Advancing methods to study ecosystem dynamics under rising biosphere novelty is the subject of the third subtheme. The fourth subtheme emphasizes the importance of integrating human perspectives into understanding, forecasting and managing novel ecosystems. Cultural diversity and biological diversity are intertwined, and the evolving relationship between humans and ecosystems offers lessons for future stewardship. Achieving planetary stewardship in the Anthropocene demands collaboration across scales and integration of ecological and societal perspectives, scalable approaches fit to changing, novel ecological conditions, as well as cultural innovation. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Harnessing eDNA metabarcoding to investigate fish community composition and its seasonal changes in the Oslo fjord

In the face of global ecosystem changes driven by anthropogenic activities, effective biomonitoring strategies are crucial for mitigating impacts on vulnerable aquatic habitats. Time series analysis underscores a great significance in understanding the dynamic nature of marine ecosystems, especially amidst climate change disrupting established seasonal patterns. Focusing on Norway's Oslo fjord, our research utilises eDNA-based monitoring for temporal analysis of aquatic biodiversity during a one year period, with bi-monthly sampling along a transect. To increase the robustness of the study, a taxonomic assignment comparing BLAST+ and SINTAX approaches was done. Utilising MiFish and Elas02 primer sets, our study detected 63 unique fish species, including several commercially important species. Our findings reveal a substantial increase in read abundance during specific migratory cycles, highlighting the efficacy of eDNA metabarcoding for fish composition characterization. Seasonal dynamics for certain species exhibit clear patterns, emphasising the method's utility in unravelling ecological complexities. eDNA metabarcoding emerges as a cost-effective tool with considerable potential for fish community monitoring for conservation purposes in dynamic marine environments like the Oslo fjord, contributing valuable insights for informed management strategies.

Understanding the response of the Western Mediterranean cephalopods to environment and fishing in a context of alleged winners of change

Increasing impacts of both fisheries and climate change have resulted in shifts in the structure and functioning of marine communities. One recurrent observation is the rise of cephalopods as fish recede. This is generally attributed to the removal of main predators and competitors by fishing, while mechanistic evidence is still lacking. In addition, climate change may influence cephalopods due to their high environmental sensitivity. We aim to unveil the effects of different anthropogenic and environmental drivers at different scales focusing on the cephalopod community of the Western Mediterranean Sea. We investigate several ecological indicators offering a wide range of information about their ecology, and statistically relating them with environmental, biotic and fisheries drivers. Our results highlight non-linear changes of indicators along with spatial differences in their responses. Overall, the environment drivers have greater effects than biotic and local human impacts with contrasting effects of temperature across the geographic gradient. We conclude that cephalopods may be impacted by climate change in the future while not necessary through positive warming influence, which should make us cautious when referring to them as generalized winners of current changes.

A marine heatwave changes the stabilizing effects of biodiversity in kelp forests

Biodiversity can stabilize ecological communities through biological insurance, but climate and other environmental changes may disrupt this process via simultaneous ecosystem destabilization and biodiversity loss. While changes to diversity-stability relationships (DSRs) and the underlying mechanisms have been extensively explored in terrestrial plant communities, this topic remains largely unexplored in benthic marine ecosystems that comprise diverse assemblages of producers and consumers. By analyzing two decades of kelp forest biodiversity survey data, we discovered changes in diversity, stability, and their relationships at multiple scales (biological organizational levels, spatial scales, and functional groups) that were linked with the most severe marine heatwave ever documented in the North Pacific Ocean. Moreover, changes in the strength of DSRs during/after the heatwave were more apparent among functional groups than both biological organizational levels (population vs. ecosystem levels) and spatial scales (local vs. broad scales). Specifically, the strength of DSRs decreased for fishes, increased for mobile invertebrates and understory algae, and were unchanged for sessile invertebrates during/after the heatwave. Our findings suggest that biodiversity plays a key role in stabilizing marine ecosystems, but the resilience of DSRs to adverse climate impacts primarily depends on the functional identities of ecological communities.

Marine fishes experiencing high-velocity range shifts may not be climate change winners

Climate change is driving the global redistribution of species. A common assumption is that rapid range shifts occur in tandem with overall stable or positive abundance trends throughout the range and thus these species may be considered as climate change 'winners'. However, although establishing the link between range shift velocities and population trends is crucial for predicting climate change impacts it has not been empirically tested. Using 2,572 estimates of changes in marine fish abundance spread across the world's oceans, we show that poleward range shifts are not necessarily associated with positive population trends. Species experiencing high-velocity range shifts seem to experience local population declines irrespective of the position throughout the species range. High range shift velocities of 17 km yr-1 are associated with a 50% decrease in population sizes over a period of 10 yr, which is dramatic compared to the overall stable population trends in non-shifting species. This pattern, however, mostly occurs in populations located in the poleward, colder, portion of the species range. The lack of a positive association between poleward range shift velocities and population trends at the coldest portion of the range contrasts with the view that rapid range shifts safeguard against local population declines. Instead, our work suggests that marine fishes experiencing rapid range shifts could be more vulnerable to climatic change and therefore should be carefully assessed for conservation status.

Global trends and scenarios for terrestrial biodiversity and ecosystem services from 1900 to 2050

Based on an extensive model intercomparison, we assessed trends in biodiversity and ecosystem services from historical reconstructions and future scenarios of land-use and climate change. During the 20th century, biodiversity declined globally by 2 to 11%, as estimated by a range of indicators. Provisioning ecosystem services increased several fold, and regulating services decreased moderately. Going forward, policies toward sustainability have the potential to slow biodiversity loss resulting from land-use change and the demand for provisioning services while reducing or reversing declines in regulating services. However, negative impacts on biodiversity due to climate change appear poised to increase, particularly in the higher-emissions scenarios. Our assessment identifies remaining modeling uncertainties but also robustly shows that renewed policy efforts are needed to meet the goals of the Convention on Biological Diversity.

Predicting Quercus gilva distribution dynamics and its response to climate change induced by GHGs emission through MaxEnt modeling

Quercus gilva, an evergreen tree species in Quercus section Cyclobalanopsis, is an ecologically and economically valuable species in subtropical regions of East Asia. Predicting the impact of climate change on potential distribution of Q. gilva can provide a scientific basis for the conservation and utilization of its genetic resources, as well as for afforestation. In this study, 74 distribution records of Q. gilva and nine climate variables were obtained after data collection and processing. Current climate data downloaded from WorldClim and future climate data predicted by four future climate scenarios (2040s SSP1-2.6, 2040s SSP5-8.5, 2060s SSP1-2.6, and 2060s SSP5-8.5) mainly based on greenhouse gases emissions of distribution sites were used in MaxEnt model with optimized parameters to predict distribution dynamics of Q. gilva and its response to climate change. The results showed that the predicted current distribution was consistent with natural distribution of Q. gilva, which was mainly located in Hunan, Jiangxi, Zhejiang, Fujian, Guizhou, and Taiwan provinces of China, as well as Japan and Jeju Island of South Korea. Under current climate conditions, precipitation factors played a more significant role than temperature factors on distribution of Q. gilva, and precipitation of driest quarter (BIO17) is the most important restriction factor for its current distribution (contribution rate of 57.35%). Under future climate conditions, mean temperature of driest quarter (BIO9) was the essential climate factor affecting future change in potential distribution of Q. gilva. As the degree of climatic anomaly increased in the future, the total area of predicted distribution of Q. gilva showed a shrinking trend (decreased by 12.24%-45.21%) and Q. gilva would migrate to high altitudes and latitudes. The research results illustrated potential distribution range and suitable climate conditions of Q. gilva, which can provide essential theoretical references for the conservation, development, and utilization of Q. gilva and other related species.

Is the threatened land crab Cardisoma guanhumi conquering human-dominated systems?

Land use changes are heralded as a major driver of biodiversity loss. However, recent findings show that cities, perhaps the most radical habitat transformation, sustain increasing numbers of threatened species. This emerging trend has been mostly chronicled for vertebrates from landlocked cities, although loss of biodiversity and rates or urbanization are higher in coastal marine systems. To advance our understanding on how threatened species may conquer human-dominated systems, we studied the threatened edible crab Cardisoma guanhumi and assessed how it is proliferating in croplands and urban systems at different spatial scales and whether populations show consequences of long-term exploitation. We gathered the data on crab populations covering the whole distribution range, including three countries reporting this as a threatened species. The abundance, distribution, and size structure of crab populations among different land uses at local scales were compared and published data for populations thriving in different habitats throughout their distribution range were compiled. We found that at local scale this species is able to thrive in natural and human-disturbed habitats, where food sources are heavily altered. At larger scales, the species showed no differences in abundance and size structure among natural and anthropogenic habitats. In areas near the southern distribution edge, crab populations were more abundant and composed of larger animals in urban areas and croplands than those in natural habitats, suggesting that human-disturbed systems are stepping stones to extend the geographic range. However, we found a long-term reduction in maximum body size, exacerbated by land use changes, that likely reflects exploitation regimes consistently targeting larger crabs. Despite its status as a threatened species, the long history of human exploitation combined with livestock farming practices may explain the proliferation of this crab in human-dominated systems, which emphasize the need to consider conservation in human-dominated systems.

Anthropogenic climate and land-use change drive short- and long-term biodiversity shifts across taxa

Climate change and habitat loss present serious threats to nature. Yet, due to a lack of historical land-use data, the potential for land-use change and baseline land-use conditions to interact with a changing climate to affect biodiversity remains largely unknown. Here, we use historical land use, climate data and species observation data to investigate the patterns and causes of biodiversity change in Great Britain. We show that anthropogenic climate change and land conversion have broadly led to increased richness, biotic homogenization and warmer-adapted communities of British birds, butterflies and plants over the long term (50+ years) and short term (20 years). Biodiversity change was found to be largely determined by baseline environmental conditions of land use and climate, especially over shorter timescales, suggesting that biodiversity change in recent periods could reflect an inertia derived from past environmental changes. Climate-land-use interactions were mostly related to long-term change in species richness and beta diversity across taxa. Semi-natural grasslands (in a broad sense, including meadows, pastures, lowland and upland heathlands and open wetlands) were associated with lower rates of biodiversity change, while their contribution to national-level biodiversity doubled over the long term. Our findings highlight the need to protect and restore natural and semi-natural habitats, alongside a fuller consideration of individual species' requirements beyond simple measures of species richness in biodiversity management and policy.

Cross-basin and cross-taxa patterns of marine community tropicalization and deborealization in warming European seas

Ocean warming and acidification, decreases in dissolved oxygen concentrations, and changes in primary production are causing an unprecedented global redistribution of marine life. The identification of underlying ecological processes underpinning marine species turnover, particularly the prevalence of increases of warm-water species or declines of cold-water species, has been recently debated in the context of ocean warming. Here, we track changes in the mean thermal affinity of marine communities across European seas by calculating the Community Temperature Index for 65 biodiversity time series collected over four decades and containing 1,817 species from different communities (zooplankton, coastal benthos, pelagic and demersal invertebrates and fish). We show that most communities and sites have clearly responded to ongoing ocean warming via abundance increases of warm-water species (tropicalization, 54%) and decreases of cold-water species (deborealization, 18%). Tropicalization dominated Atlantic sites compared to semi-enclosed basins such as the Mediterranean and Baltic Seas, probably due to physical barrier constraints to connectivity and species colonization. Semi-enclosed basins appeared to be particularly vulnerable to ocean warming, experiencing the fastest rates of warming and biodiversity loss through deborealization.

Effects of short- and long-term plant functional group loss on alpine meadow community structure and soil nutrients

The rapid loss of global biodiversity can greatly affect the normal functioning of ecosystems. However, how biodiversity losses affect plant community structure and soil nutrients is unclear. We conducted a field experiment to examine the short- and long-term effects of removing plant functional groups (Gramineae, Cyperaceae, legumes, and forbs) on the interrelationships among the species diversity, productivity, community structure, and soil nutrients in an alpine meadow ecosystem at Menyuan County, Qinghai Province. The variations in the species richness, above- and belowground biomass of the community gradually decreased over time. Species richness and productivity were positively correlated, and this correlation tended to be increasingly significant over time. Removal of the Cyperaceae, legumes, and other forbs resulted in fewer Gramineae species in the community. Soil total nitrogen, phosphorus, organic matter, and moisture contents increased significantly in the legume removal treatment. The removal of other forbs led to the lowest negative cohesion values, suggesting that this community may have difficulty recovering its previous equilibrium state within a short time. The effects of species removal on the ecosystem were likely influenced by the species structure and composition within the community. Changes in the number of Gramineae species indicated that they were more sensitive and less resistant to plant functional group removal. Legume removal may also indirectly cause distinct community responses through starvation and compensation effects. In summary, species loss at the community level led to extensive species niche shifts, which caused community resource redistribution and significant changes in community structure.

Multi-decadal improvements in the ecological quality of European rivers are not consistently reflected in biodiversity metrics

Humans impact terrestrial, marine and freshwater ecosystems, yet many broad-scale studies have found no systematic, negative biodiversity changes (for example, decreasing abundance or taxon richness). Here we show that mixed biodiversity responses may arise because community metrics show variable responses to anthropogenic impacts across broad spatial scales. We first quantified temporal trends in anthropogenic impacts for 1,365 riverine invertebrate communities from 23 European countries, based on similarity to least-impacted reference communities. Reference comparisons provide necessary, but often missing, baselines for evaluating whether communities are negatively impacted or have improved (less or more similar, respectively). We then determined whether changing impacts were consistently reflected in metrics of community abundance, taxon richness, evenness and composition. Invertebrate communities improved, that is, became more similar to reference conditions, from 1992 until the 2010s, after which improvements plateaued. Improvements were generally reflected by higher taxon richness, providing evidence that certain community metrics can broadly indicate anthropogenic impacts. However, richness responses were highly variable among sites, and we found no consistent responses in community abundance, evenness or composition. These findings suggest that, without sufficient data and careful metric selection, many common community metrics cannot reliably reflect anthropogenic impacts, helping explain the prevalence of mixed biodiversity trends.

Past and recent anthropogenic pressures drive rapid changes in riverine fish communities

Understanding how and why local communities change is a pressing task for conservation, especially in freshwater systems. It remains challenging because of the complexity of biodiversity changes, driven by the spatio-temporal heterogeneity of human pressures. Using a compilation of riverine fish community time series (93% between 1993 and 2019) across the Palaearctic, Nearctic and Australasia realms, we assessed how past and recent anthropogenic pressures drive community changes across both space and time. We found evidence of rapid changes in community composition of 30% per decade characterized by important changes in the dominant species, together with a 13% increase in total abundance per decade and a 7% increase in species richness per decade. The spatial heterogeneity in these trends could be traced back to the strength and timing of anthropogenic pressures and was mainly mediated by non-native species introductions. Specifically, we demonstrate that the negative effects of anthropogenic pressures on species richness and total abundance were compensated over time by the establishment of non-native species, a pattern consistent with previously reported biotic homogenization at the global scale. Overall, our study suggests that accounting for the complexity of community changes and its drivers is a crucial step to reach global conservation goals.

A Global Systematic Literature Review of Ecosystem Services in Reef Environments

Ecosystem services (ES) embrace contributions of nature to human livelihood and well-being. Reef environments provide a range of ES with direct and indirect contributions to people. However, the health of reef environments is declining globally due to local and large-scale threats, affecting ES delivery in different ways. Mapping scientific knowledge and identifying research gaps on reefs' ES is critical to guide their management and conservation. We conducted a systematic assessment of peer-reviewed articles published between 2007 and 2022 to build an overview of ES research on reef environments. We analyzed the geographical distribution, reef types, approaches used to assess ES, and the potential drivers of change in ES delivery reported across these studies. Based on 115 articles, our results revealed that coral and oyster reefs are the most studied reef ecosystems. Cultural ES (e.g., subcategories recreation and tourism) was the most studied ES in high-income countries, while regulating and maintenance ES (e.g., subcategory life cycle maintenance) prevailed in low and middle-income countries. Research efforts on reef ES are biased toward the Global North, mainly North America and Oceania. Studies predominantly used observational approaches to assess ES, with a marked increase in the number of studies using statistical modeling during 2021 and 2022. The scale of studies was mostly local and regional, and the studies addressed mainly one or two subcategories of reefs' ES. Overexploitation, reef degradation, and pollution were the most commonly cited drivers affecting the delivery of provisioning, regulating and maintenance, and cultural ES. With increasing threats to reef environments, the growing demand for assessing the contributions to humans provided by reefs will benefit the projections on how these ES will be impacted by anthropogenic pressures. The incorporation of multiple and synergistic ecosystem mechanisms is paramount to providing a comprehensive ES assessment, and improving the understanding of functions, services, and benefits.

Depth variation in benthic community response to repeated marine heatwaves on remote Central Indian Ocean reefs

Coral reefs are increasingly impacted by climate-induced warming events. However, there is limited empirical evidence on the variation in the response of shallow coral reef communities to thermal stress across depths. Here, we assess depth-dependent changes in coral reef benthic communities following successive marine heatwaves from 2015 to 2017 across a 5-25 m depth gradient in the remote Chagos Archipelago, Central Indian Ocean. Our analyses show an overall decline in hard and soft coral cover and an increase in crustose coralline algae, sponge and reef pavement following successive marine heatwaves on the remote reef system. Our findings indicate that the changes in benthic communities in response to elevated seawater temperatures varied across depths. We found greater changes in benthic group cover at shallow depths (5-15 m) compared with deeper zones (15-25 m). The loss of hard coral cover was better predicted by initial thermal stress, while the loss of soft coral was associated with repeated thermal stress following successive warming events. Our study shows that benthic communities extending to 25 m depth were impacted by successive marine heatwaves, supporting concerns about the resilience of shallow coral reef communities to increasingly severe climate-driven warming events.

Marine protected areas promote stability of reef fish communities under climate warming

Protection from direct human impacts can safeguard marine life, yet ocean warming crosses marine protected area boundaries. Here, we test whether protection offers resilience to marine heatwaves from local to network scales. We examine 71,269 timeseries of population abundances for 2269 reef fish species surveyed in 357 protected versus 747 open sites worldwide. We quantify the stability of reef fish abundance from populations to metacommunities, considering responses of species and functional diversity including thermal affinity of different trophic groups. Overall, protection mitigates adverse effects of marine heatwaves on fish abundance, community stability, asynchronous fluctuations and functional richness. We find that local stability is positively related to distance from centers of high human density only in protected areas. We provide evidence that networks of protected areas have persistent reef fish communities in warming oceans by maintaining large populations and promoting stability at different levels of biological organization.

Synthesis reveals approximately balanced biotic differentiation and homogenization

It is commonly thought that the biodiversity crisis includes widespread declines in the spatial variation of species composition, called biotic homogenization. Using a typology relating homogenization and differentiation to local and regional diversity changes, we synthesize patterns across 461 metacommunities surveyed for 10 to 91 years, and 64 species checklists (13 to 500+ years). Across all datasets, we found that no change was the most common outcome, but with many instances of homogenization and differentiation. A weak homogenizing trend of a 0.3% increase in species shared among communities/year on average was driven by increased numbers of widespread (high occupancy) species and strongly associated with checklist data that have longer durations and large spatial scales. At smaller spatial and temporal scales, we show that homogenization and differentiation can be driven by changes in the number and spatial distributions of both rare and common species. The multiscale perspective introduced here can help identify scale-dependent drivers underpinning biotic differentiation and homogenization.