Linking the influence and dependence of people on biodiversity across scales

Return of diversity: Wetland plant community recovery following purple loosestrife biocontrol

Spread of non-native species can be important drivers of biodiversity declines, leading to precautionary management based on assumptions that (1) non-native biota have negative impacts and are "guilty" of causing harm and (2) reducing a non-native species' abundance will reduce these negative impacts, in turn, benefiting native species. However, we frequently lack data to gauge both negative impacts of non-native species and success or failure of chosen management interventions to benefit native species. Addressing these knowledge gaps is critical to improving management outcomes for native species while maintaining public trust to sustain funding of management activities. Here, we investigated the response of Lythrum salicaria (purple loosestrife) and associated plant communities to implementation of biological control in more than 10 wetland sites in New York State for up to 28 years. Introduced to North America from Europe in the 1800s, L. salicaria is a prime example of a non-native species with a continent-wide distribution that could not be suppressed by mechanical and chemical treatments. In the 1980s, waterfowl biologists, wetland managers, and conservationists alike worried about the loss of diverse wetland plant communities associated with the rapid expansion of L. salicaria. In response, after careful assessments of safety, and potential costs and benefits, four highly host-specific insect herbivores were released in North America in the early 1990s to reduce L. salicaria abundance and its negative ecological impacts. In a companion paper, Blossey et al. documented reduced L. salicaria occupancy and stem densities following insect releases over time (i.e., biological success), irrespective of site-specific differences in starting plant communities or L. salicaria abundance. Here, we show that reduced abundance of L. salicaria leads to the ultimate goal of non-native plant management: increased cover, abundance, and diversity of species, often of native species (i.e., ecological success). We also conduct analyses to provide inference about which plant species are most sensitive to L. salicaria, including changes in L. salicaria stem density. Overall, we provide an important conservation success story: our findings emphasize that biocontrol of non-native plants can be effective and safe, allowing native species to recover as a dominant non-native species gradually declines.

Effects of Multiscale Environmental Variables on the Taxonomic and Functional Structures of Riverine Microeukaryotic Plankton Communities: eDNA Metabarcoding and Metatranscriptomic Perspectives

Research on the impact of multiscale complex environmental variables on the structure and function of aquatic communities is currently at the forefront, yet the gene regulatory mechanisms of aquatic communities remain poorly understood. In this study, we investigated the Yongding River watershed, a model system exhibiting pronounced environmental factors across "mountain-plain-coastal" sections and three spatial scales of "basin-reach-site". Through integrated eDNA metabarcoding and metatranscriptomics, we revealed that environmental factors at different scales significantly influence riverine microeukaryotic plankton community composition and functional genes expression profiles, which may be related to basin- and reach-scale variables indirectly influencing site-scale physiochemical conditions. Under multiscale environmental gradients, community composition and functional genes expression differed across mountain-plain-coastal sections, but genes expression demonstrated remarkable spatial stability than community composition. Cross-scale environmental factors similarly impacted community composition, functional genes expression, and biogenic element metabolism, or differently influenced them in varying ways. At each scale of "basin-reach-site", the sensitivity of community composition and functional genes expression varied in their responses to different environmental factors. This decoupling of taxonomic and functional responses highlights the complexity of community-environment interactions across spatial hierarchies. This study develops a novel framework that integrates meta-omics signatures derived from environmental samples with cross-scale environmental drivers in aquatic ecosystems, effectively bridging micro-scale molecular responses with macro-scale ecosystem patterns.

Plant species richness promotes the decoupling of leaf and root defence traits while species-specific responses in physical and chemical defences are rare

The increased positive impact of plant diversity on ecosystem functioning is often attributed to the accumulation of mutualists and dilution of antagonists in diverse plant communities. While increased plant diversity alters traits related to resource acquisition, it remains unclear whether it reduces defence allocation, whether this reduction differs between roots and leaves, or varies among species. To answer these questions, we assessed the effect of plant species richness, plant species identity and their interaction on the expression of 23 physical and chemical leaf and fine root defence traits of 16 plant species in a 19-yr-old biodiversity experiment. Only leaf mass per area, leaf and root dry matter content and root nitrogen, traits associated with both, resource acquisition and defence, responded consistently to species richness. However, species richness promoted a decoupling of these defences in leaves and fine roots, possibly in response to resource limitations in diverse communities. Species-specific responses were rare and related to chemical defence and mutualist collaboration, likely responding to species-specific antagonists' dilution and mutualists' accumulation. Overall, our study suggests that resource limitation in diverse communities might mediate the relationship between plant defence traits and antagonist dilution.

Plant Acquisitive Strategies Promote Resistance and Temporal Stability of Semiarid Grasslands

Among ecologists, it is widely believed that conservative growth strategies of plants are crucial for sustaining ecosystem stability, while the potential stabilising role of acquisitive strategies has received little attention. We investigated the relationships between plant traits and three stability dimensions-temporal stability, resistance and resilience-using two complementary datasets from drought-affected semi-arid grasslands: a temporal plant community survey from a single site and a 1000-km transect survey with satellite-derived productivity estimates. We found strikingly consistent patterns from the two datasets, with grasslands dominated by acquisitive strategies exhibiting greater resistance and temporal stability of productivity. Acquisitive strategies enhance stability by facilitating drought escape and avoidance, rather than drought tolerance typically associated with conservative strategies. These results highlight the important but underappreciated role of acquisitive strategies in enhancing ecosystem resistance to disturbances and maintaining temporal stability in semi-arid grasslands.

Shared community history strengthens plant diversity effects on below-ground multitrophic functioning

The relationship of plant diversity and several ecosystem functions strengthens over time. This suggests that the restructuring of biotic interactions in the process of a community's assembly and the associated changes in function differ between species-rich and species-poor communities. An important component of these changes is the feedback between plant and soil community history. In this study, we examined the interactive effects of plant richness and community history on the trophic functions of the soil fauna community. We hypothesized that experimental removal of either soil or plant community history would diminish the positive effects of plant richness on the multitrophic functions of the soil food web, compared to mature communities. We tested this hypothesis in a long-term grassland biodiversity experiment by comparing plots across three treatments (without plant history, without plant and soil history, controls with ~20 years of plot-specific community history). We found that the relationship between plant richness and below-ground multitrophic functionality is indeed stronger in communities with shared plant and soil community history. Our findings indicate that anthropogenic disturbance can impact the functioning of the soil community through the loss of plant species but also by preventing feedbacks that develop in the process of community assembly.

Unifying spatial scaling laws of biodiversity and ecosystem stability

While both species richness and ecosystem stability increase with area, how these scaling patterns are linked remains unclear. Our theoretical and empirical analyses of plant and fish communities show that the spatial scaling of ecosystem stability is determined primarily by the scaling of species asynchrony, which is in turn driven by the scaling of species richness. In wetter regions, plant species richness and ecosystem stability both exhibit faster accumulation with area, implying potentially greater declines in biodiversity and stability following habitat loss. The decline in ecosystem stability after habitat loss can be delayed, creating a stability debt mirroring the extinction debt of species. By unifying two foundational scaling laws in ecology, our work underscores that ongoing biodiversity loss may destabilize ecosystems across spatial scales.

Macroecological rules predict how biomass scales with species richness in nature

Despite advances in theory and experiments, how biodiversity influences the structure and functioning of natural ecosystems remains debated. By applying new theory to data on 84,695 plant, animal, and protist assemblages, we show that the general positive effect of species richness on stocks of biomass, as well as much of the variation in the strength and sign of this effect, is predicted by a fundamental macroecological quantity: the scaling of species abundance with body mass. Standing biomass increases with richness when large-bodied species are numerically rare but is independent of richness when species size and abundance are uncoupled. These results suggest a new fundamental law in the structure of ecological communities and show that the impacts of changes in species richness on biomass are predictable.

Relationship Between Plant Diversity and Soil Environment in Karst Urban Remnant Mountains: A Comparative Analysis of Two Types

Understanding the characteristics of plant diversity and its relationship with the soil environment in urban remnant habitats before and after their transformation into parks is of great significance for strengthening urban biodiversity conservation. To investigate the changes in plant diversity characteristics and their relationship with the soil environment following the transformation of urban remnant natural mountains (URNM) into urban remnant mountain parks (URMP), we conducted a study in the urban area of Guiyang City, China. We sampled 90 plots across five typical URNM and five typical URMP. Plant diversity and its relationship with soil properties were evaluated using four taxonomic diversity indices and 9 soil physicochemical properties. The results showed that URNM exhibited higher plant diversity and richer species richness compared to URMP. In URNM, plant survival conditions deteriorate with the elevation of slope position, resulting in the highest plant diversity at lower slopes and the lowest at upper slopes. However, intense human disturbances lead to the opposite pattern in URMP. Additionally, soil bulk density, total phosphorus, and total potassium (TK) were found to be higher in URMP than in URNM. C/N, C/P, and soil organic carbon were identified as the main factors influencing plant diversity in URNM, with explanatory rates of 20.1%, 15.4%, and 8.6%, respectively. In URMP, TK was the most significant factor, explaining over 55.9% of plant diversity. These findings indicate that the transformation of karst urban remnant mountains into parks leads to a simplification of plant species composition and a reduction in plant diversity. This process also alters the characteristics of soil environmental factors and their relationship with plant diversity. These changes highlight the need for careful management strategies in urban park development to mitigate biodiversity loss and maintain soil health, which are crucial for the sustainability of urban ecosystems.

Ectomycorrhizal Dominance Increases Temporal Stability of Productivity at Multiple Spatial Scales Across US Forests

Mycorrhizas are fundamental to plant productivity and plant diversity maintenance, yet their influence on the temporal stability of forest productivity across scales remains uncertain. The multiscale stability theory clarifies that the temporal stability (γ stability) of metacommunity-several local communities connected through species dispersal-can be decomposed into the temporal stability of local communities (α stability) and asynchrony among them. Here, based on the forest inventory dataset from the United States and the multiscale stability theory, we explored how mycorrhizal strategy influences forest stability across scales and their underlying mechanisms. At the local scale, we found that α stability increased with ectomycorrhizal dominance due to the higher temporal stability of ectomycorrhizal trees. Additionally, higher α diversity associated with mixed mycorrhizal strategies promoted species asynchrony. At the metacommunity scale, the stabilizing effect of ectomycorrhizal dominance surpassed that of mixed mycorrhizal strategies on the asynchrony among local communities (i.e., spatial asynchrony), resulting in higher γ stability with increasing ectomycorrhizal dominance. Our research suggests the stabilizing effects of ectomycorrhizal dominance on the temporal stability of forest productivity, highlighting the importance of protecting ectomycorrhizal forests to maintain productivity under climate change, especially in the boreal-temperate ecotone where ectomycorrhizal trees are threatened by global change.

Effects of socioeconomic and human-modified landscape variables on medicinal species richness at a macroscale: the case of the Caatinga, Brazil

BACKGROUND

Ethnobiological studies at local scales have shown that knowledge of medicinal species tends to decrease as socioeconomic status and the extent of human-modified landscapes increase. However, it remains largely unknown whether these same factors can predict knowledge of useful species at broader scales and whether their interaction might create scenarios that enhance knowledge of medicinal species.

METHODS

To address this, we tested whether knowledge of woody medicinal species-measured as the number of species known-is influenced by socioeconomic status, human-modified landscapes, and their interaction. We compiled and curated data on woody medicinal species from a systematic review encompassing diverse communities across the Caatinga region in North-east Brazil. Using the locations of these communities, we extracted data on socioeconomic status (measured by the Human Development Index, HDI) and human-modified landscapes (quantified as the percentage of forest loss).

RESULTS

Our results indicate that forest loss reduces the knowledge of medicinal woody species among Indigenous People and Local Communities. The interaction between human-modified landscapes and socioeconomic status revealed a significant nonlinear relationship, with different combinations yielding varying levels of knowledge about woody medicinal species. Interestingly, socioeconomic status alone does not appear to influence this knowledge. These findings underscore that the processes shaping knowledge of medicinal species differ across scales and suggest the existence of yet unidentified emergent properties that influence medicinal species knowledge at broader scales.

CONCLUSION

The conversion of habitats for anthropogenic use poses a significant risk to the well-being of these populations, as it reduces the availability of species used for prophylactic purposes. In contrast, the cultural traditions of Indigenous People and Local Communities, along with the implementation of regional public policies, may explain why socioeconomic status does not affect local knowledge. Moreover, our study highlights that the processes influencing knowledge of medicinal species at broader scales are not simply the aggregation of local-scale observations. Finally, we propose strategies to advance the field of macroethnobiology.

Temporal and habitat-specific variations in drivers of aboveground biomass dynamics in a Chinese subtropical forest

Understanding the mechanisms governing biodiversity-biomass relationships across temporal and spatial scales is essential for elucidating how abiotic and biotic factors influence ecosystem function in natural forests. However, the simultaneous contributions of multiple abiotic (e.g., topography) and biotic factors (e.g., structural diversity) to aboveground biomass dynamics (ΔAGB) over time and across habitat types remain inadequately understood. To address this gap, we evaluated changes in aboveground biomass across a decade and various habitats, disentangling the relative influences of topography and multidimensional diversity on ΔAGB through datasets from forest inventories conducted between 2007 and 2017, along with phylogenetic relatedness, functional traits, and environmental variables from a subtropical forest in China. Our findings indicate that aboveground biomass at community level experienced a significant decline followed by an increase over the decade, predominantly driven by changes in the low-valley habitat. In contrast, no statistically significant alterations were detected in the aboveground biomass of mid-hillside and high-ridge habitats. Furthermore, the determinants of ΔAGB exhibited temporal variation. During the 2007-2012 period, ΔAGB was primarily influenced by functional and structural diversity, accounting for 66.11% and 21.35% of relative importance, respectively. In the subsequent 2012-2017 period, phylogenetic and structural diversity emerged as key factors, explaining 48.46% and 36.43% of relative importance, respectively. Additionally, we observed that the drivers and effects impacting ΔAGB exhibited significant variability across different habitat types. In summary, our study underscores the significant spatiotemporal dependence of abiotic and biotic drivers on biomass dynamics within forest ecosystems, thereby enhancing our understanding of the complex biodiversity-ecosystem functioning relationships.

Towards a 'people and nature' paradigm for biodiversity and infectious disease

Zoonotic and vector-borne infectious diseases are among the most direct human health consequences of biodiversity change. The COVID-19 pandemic increased health policymakers' attention on the links between ecological degradation and disease, and sparked discussions around nature-based interventions to mitigate zoonotic emergence and epidemics. Yet, although disease ecology provides an increasingly granular knowledge of wildlife disease in changing ecosystems, we still have a poor understanding of the net consequences for human disease. Here, we argue that a renewed focus on wildlife-borne diseases as complex socio-ecological systems-a 'people and nature' paradigm-is needed to identify local interventions and transformative system-wide changes that could reduce human disease burden. We discuss longstanding scientific narratives of human involvement in zoonotic disease systems, which have largely framed people as ecological disruptors, and discuss three emerging research areas that provide wider system perspectives: how anthropogenic ecosystems construct new niches for infectious disease, feedbacks between disease, biodiversity and social vulnerability and the role of human-to-animal pathogen transmission ('spillback') in zoonotic disease systems. We conclude by discussing new opportunities to better understand the predictability of human disease outcomes from biodiversity change and to integrate ecological drivers of disease into health intervention design and evaluation.This article is part of the discussion meeting issue 'Bending the curve towards nature recovery: building on Georgina Mace's legacy for a biodiverse future'.

Effects of fertilizer application on the bacterial community and weathering characteristics of typical purple parent rocks

Introduction

Rock weathering is a fundamental process that shapes Earth's topography, soil formation, and other surface processes. However, the mechanisms underlying the influence of fertilizer application on weathering remain poorly understood, especially with respect to bacterial intervention.

Methods

In this study, purple parent rocks from Shaximiao Group (J2s) and Penglaizhen Group (J3p) were selected to investigate the effects of fertilizer application on the bacterial community and weathering characteristics of these rock by leaching experiment.

Results

The results revealed that: fertilizer application, especially when at high levels, greatly altered the abundance, diversity and composition of the bacterial community in weathered products. Through redundancy analysis, a decrease in pH and increases in available nutrients (AN and AP) resulting from fertilizer application were identified as the key factors driving changes of bacterial community composition in weathered products. Moreover, fertilizer application promotes the physical and chemical weathering of the parent rocks to some extent. This is especially true for the chemical weathering of J2s. Structural equation model indicated that fertilizer application affects weathering through multiple pathways by affecting the chemical properties (pH, C:N and AP), specific bacterial genera (IMCC26256, Ramlibacter, and Nitrosospira), and bacterial community composition of weathered products.

Discussion

Our study links weathering characteristics with chemical properties and bacterial community changes of weathered products after fertilizer application, which plays a key role in controlling and predicting dynamic changes of rock weathering in space and time. It is helpful to further understand the law of human activities affecting the surface processes.

Distinct effects of flow intermittency on the benthic microbial diversity and their denitrification on different substrates

Global climate change has significantly increased the duration of droughts in intermittent rivers, impacting benthic microbial-mediated biogeochemical processes. However, the response mechanisms of biofilms on different substrate types to alternating dry and wet conditions and their related ecosystem functions remain poorly understood. This study uses high-throughput sequencing and enzyme assays to investigate the impact of gradient drought stress on microbial diversity and functional changes of biofilm communities inhabiting on gravel, cobblestone, and sediment. Results showed that the duration of drought significantly affects microbial diversity, with algal and bacterial α-diversity declining under extended drought across gravel, cobblestone, and sediment substrates. At the same time, fungal diversity was less affected, likely due to their distinct ecological niches and reproductive strategies. β-diversity analysis revealed significant changes in community heterogeneity, with algae and bacteria showing increased Bray-Curtis dissimilarities, indicating distinct adaptation strategies that may affect ecosystem functioning. Fungal communities, however, were less impacted by drought-induced heterogeneity changes. Network analysis showed that drought altered microbial network connectivity, with algal networks displaying decreased path distances, while bacterial networks remained stable, suggesting greater resilience to drought stress. Functional enzyme assays revealed significantly reduced denitrification rates across all substrates post-drought, with distinct denitrifying enzyme activity responses depending on substrate type. Partial least squares path modeling revealed that algal biodiversity were closely linked to the maintaining of enzyme activities, particularly denitrification rates of biofilms on cobblestone and gravel. These findings indicated the critical role of substrate types in shaping microbial responses to drought stress, with distinct microbial groups and diversity indices playing key roles in maintaining ecosystem functions. This study highlights the importance of understanding the interactions between microbial community dynamics and ecosystem functions under varying environmental stressors in river ecosystems.

Early allelopathic input and later nutrient addition mediated by litter decomposition of invasive Solidago canadensis affect native plant and facilitate its invasion

Litter decomposition is essential for nutrient and chemical cycling in terrestrial ecosystems. Previous research on in situ litter decomposition has often underestimated its impact on soil nutrient dynamics and allelopathy. To address this gap, we conducted a comprehensive study involving both field and greenhouse experiments to examine the decomposition and allelopathic effects of the invasive Solidago canadensis L. in comparison with the native Phalaris arundinacea L. In the field, a 6-month litter bag experiment using leaf litter from S. canadensis and P. arundinacea was conducted across three community types: invasive, native, and mixed. Seed germination tests were also performed to investigate the allelopathic effects of decomposing litter. In the greenhouse, a pot experiment with lettuce as a bioindicator was performed to examine the allelochemical inputs from litter decomposition over various time intervals (0, 30, 60, 120, and 180 days). Subsequently, a soil-plant feedback experiment was carried out to further evaluate the effects of decomposing litter on soil biochemistry and plant dynamics. The findings of this study revealed that S. canadensis litter decomposed more rapidly and exhibited greater nitrogen (N) remaining mass compared with P. arundinacea in both single and mixed communities. After 180 days, the values for litter mass remaining for S. canadensis and P. arundinacea were 36% and 43%, respectively, when grown separately and were 32% and 44%, respectively, in mixed communities. At the invasive site, the soil ammonia and nitrate for S. canadensis increased gradually, reaching 0.89 and 14.93 mg/kg by day 120, compared with the native site with P. arundinacea. The soil organic carbon for S. canadensis at the invasive site also increased from 10.6 mg/kg on day 0 to 15.82 mg/kg on day 120, showing a higher increase than that at the native site with P. arundinacea. During the initial decomposition stages, all litters released almost all of their allelochemicals. However, at the later stages, litters continued to input nutrients into the soil, but had no significant impact on the soil carbon (C) and N cycling. Notably, litter-mediated plant-soil feedback facilitated the invasion of S. canadensis. In conclusion, this study highlights the significance of litter decomposition as a driver of transforming soil biochemistry, influencing the success of invasive S. canadensis.

The spatiotemporal stability of plant diversity is disconnected from biomass stability in response to human activities in a South American temperate grassland

Human activities alter biomass, nutrient availability, and species dominance in grasslands, impacting their richness, composition, and biomass production. Stability (invariability in time or space) can inform the predictability of plant communities in response to human activities. However, this measure has been simplistically analyzed for temporal (interannual) changes in live biomass, disregarding their spatial stability and the temporal stability of other plant community attributes. Moreover, the simultaneous analysis of temporal and spatial stabilities of plant communities has been scarcely assessed. Here, we test how biomass removal and nutrient addition simultaneously modify the temporal and spatial stabilities of plant richness (α diversity), composition dissimilarity (β diversity), aboveground live biomass, and the role of plant species dominance in the stability responses. We conducted a factorial experiment of biomass removal (grazing, mowing, or intact -no removal-) and nutrient addition (unfertilized or fertilized with nitrogen, phosphorus, and potassium) in a temperate grassland of Argentina, South America. We replicated the experiment in 6 blocks over 10 years to estimate the temporal and spatial stabilities of the plant community. The spatiotemporal stability of plant richness and composition dissimilarity decreased in the intact grassland, while the temporal stability of live biomass increased, compared to the grazed and mowed grasslands. Nutrient addition reduced the spatiotemporal stability of live biomass and the spatial stability of plant richness. The stabilities of species richness as well as that of composition dissimilarity were negatively associated with plant dominance, while the live biomass stability was not. Our results suggest that simplifying the effect of biomass removal and nutrient addition on grassland stability is not feasible, as plant diversity stability responses are not surrogates for biomass stability. The contrasting spatiotemporal stability responses of plant diversity and biomass represent a step forward in predicting human activities' impact over time and across space in temperate grasslands.

New York State Climate Impacts Assessment Chapter 05: Ecosystems

The people of New York have long benefited from the state's diversity of ecosystems, which range from coastal shorelines and wetlands to extensive forests and mountaintop alpine habitat, and from lakes and rivers to greenspaces in heavily populated urban areas. These ecosystems provide key services such as food, water, forest products, flood prevention, carbon storage, climate moderation, recreational opportunities, and other cultural services. This chapter examines how changes in climatic conditions across the state are affecting different types of ecosystems and the services they provide, and considers likely future impacts of projected climate change. The chapter emphasizes how climate change is increasing the vulnerability of ecosystems to existing stressors, such as habitat fragmentation and invasive species, and highlights opportunities for New Yorkers to adapt and build resilience.

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.

Interbasin trade worsens the state of freshwater fish biodiversity in China

Human economic activities severely threaten freshwater fish biodiversity in different river basins. Trade makes the impact more mysterious and complex and confounds local efforts to protect freshwater biodiversity. To investigate the relationship between trade and freshwater fishes, we developed a river-basin economic transaction model that is applied to mainland China, home to 9% of the world's freshwater fish species. Here, we show that interbasin trade induced by final demand contributes 74% of the threats to China's freshwater fish biodiversity. Economically developed river basins (e.g., the Huaihe River) are the main beneficiaries of interbasin trade at the cost of biodiversity deterioration in economically underdeveloped river basins (e.g., the upper Pearl River), especially when trade occurs between distant basins. Our findings highlight the significance of the shift in governance from administrative divisions to river basins and control measures in different stages of economic supply chains to mitigate freshwater fish biodiversity threats.

Landscape and environmental heterogeneity support coexistence in competitive metacommunities

Metapopulation models have been instrumental in quantifying the ecological impact of landscape structure on the survival of a focal species. However, extensions to multiple species with arbitrary dispersal networks often rely on phenomenological assumptions that inevitably limit their scope. Here, we propose a multilayer network model of competitive dispersing metacommunities to investigate how spatially structured environments impact species coexistence and ecosystem stability. We introduce the concept of landscape-mediated fitness, quantifying how fit a species is in a given environment in terms of colonization and extinction. We show that, when all environments are equivalent, one species excludes all the others-except the marginal case where species fitnesses are in exact trade-off. However, we prove that stable coexistence becomes possible in sufficiently heterogeneous environments by introducing spatial disorder in the model and solving it exactly in the mean-field limit. Crucially, coexistence is supported by the spontaneous localization of species through the emergence of ecological niches. We show that our results remain qualitatively valid in arbitrary dispersal networks, where topological features can improve species coexistence by buffering competition. Finally, we employ our model to study how correlated heterogeneity promotes spatial ecological patterns in realistic terrestrial and riverine landscapes. Our work provides a framework to understand how landscape structure enables coexistence in metacommunities by acting as the substrate for ecological interactions.

Disruptive Technologies and Open Science: How Open Should Open Science Be? A 'Third Bioethics' Ethical Framework

This paper investigates the ethical implications of applying open science (OS) practices on disruptive technologies, such as generative AIs. Disruptive technologies, characterized by their scalability and paradigm-shifting nature, have the potential to generate significant global impact, and carry a risk of dual use. The tension arises between the moral duty of OS to promote societal benefit by democratizing knowledge and the risks associated with open dissemination of disruptive technologies. Van Rennselaer Potter's 'third bioethics' serves as the founding horizon for an ethical framework to govern these tensions. Through theoretical analysis and concrete examples, this paper explores how OS can contribute to a better future or pose threats. Finally, we provide an ethical framework for the intersection between OS and disruptive technologies that tries to go beyond the simple 'as open as possible' tenet, considering openness as an instrumental value for the pursuit of other ethical values rather than as a principle with prima facie moral significance.

Early detection of human impacts using acoustic monitoring: An example with forest elephants

The impacts of human activities and climate change on animal populations often take considerable time before they are reflected in typical measures of population health such as population size, demography, and landscape use. Earlier detection of such impacts could enhance the effectiveness of conservation strategies, particularly for species with slow population growth. Passive acoustic monitoring is increasingly used to estimate occupancy and population size, but this tool can also monitor subtle shifts in behavior that might be early indicators of changing impacts. Here we use data from an acoustic grid, monitoring 1250 km2 of forest in northern Republic of Congo, to study how forest elephants (Loxodonta cyclotis) assess risk associated with human impacts across a landscape that includes a national park as well as active and inactive logging concessions. By quantifying emerging patterns of behavior at the population level, arising from individual-based decisions, we gain an understanding of how elephants perceive their landscape along an axis of human disturbance. Forest elephants in relatively undisturbed forests are active nearly equally day and night. However, they become more nocturnal when exposed to a perceived risk such as poaching. We assessed elephant perception of risk by monitoring changes in the likelihood of nocturnal vocal activity relative to differing levels of human activity. We show that logging is perceived to be a risk on moderate time and small spatial scales, but with little effect on elephant density. However, risk avoidance persisted in areas with relatively easy access to poachers and in more open habitats where poaching has historically been concentrated. Increased nocturnal activity is a common response in many animals to human intrusion on the landscape. Provided a species is acoustically active, passive acoustic monitoring can measure changes in human impact at early stages of such change, informing management priorities.

Ecology: Operationalize biodiversity theory

The rise in global population and consumption intensifies the demand for ecosystem services, especially in agriculture. Recent research underscores the societal benefits of biodiversity. Operationalizing biodiversity theory and embracing diverse agricultural practices can enhance sustainability, supporting food security and climate resilience.

Regional microbial biogeography linked to soil respiration

The relationships between α-diversity and ecosystem functioning (BEF) have been extensively examined. However, it remains unknown how spatial heterogeneity of microbial community, i.e., microbial β-diversity within a region, shapes ecosystem functioning. Here, we examined microbial community compositions and soil respiration (Rs) along an elevation gradient of 853-4420 m a.s.l. in the southeastern Tibetan Plateau, which is renowned as one of the world's biodiversity hotspots. There were significant distance-decay relationships for both bacterial and fungal communities. Stochastic processes played a dominant role in shaping bacterial and fungal community compositions, while soil temperature was the most important environmental factor that affected microbial communities. We evaluated BEF relationships based on α-diversity measured by species richness and β-diversity measured by community dispersions, revealing significantly positive correlations between microbial β-diversities and Rs. These correlations became stronger with increasing sample size, differing from those between microbial α-diversities and Rs. Using Structural Equation Modeling (SEM), we found that soil temperature, soil moisture, and total nitrogen were the most important edaphic properties in explaining Rs. Meanwhile, stochastic processes (e.g., homogenous dispersal and dispersal limitation) significantly mediated effects between microbial β-diversities and Rs. Microbial α-diversity poorly explained Rs, directly or indirectly. In a nutshell, we identified a previously unknown BEF relationship between microbial β-diversity and Rs. By complementing common practices to examine BEF with α-diversity, we demonstrate that a focus on β-diversity could be leveraged to explain Rs.

Guiding seed movement: environmental heterogeneity drives genetic differentiation in Plathymenia reticulata, providing insights for restoration

Forest and landscape restoration is one of the main strategies for overcoming the environmental crisis. This activity is particularly relevant for biodiversity-rich areas threatened by deforestation, such as tropical forests. Efficient long-term restoration requires understanding the composition and genetic structure of native populations, as well as the factors that influence these genetic components. This is because these populations serve as the seed sources and, therefore, the gene reservoirs for areas under restoration. In the present study, we investigated the influence of environmental, climatic and spatial distance factors on the genetic patterns of Plathymenia reticulata, aiming to support seed translocation strategies for restoration areas. We collected plant samples from nine populations of P. reticulata in the state of Bahia, Brazil, located in areas of Atlantic Forest and Savanna, across four climatic types, and genotyped them using nine nuclear and three chloroplast microsatellite markers. The populations of P. reticulata evaluated generally showed low to moderate genotypic variability and low haplotypic diversity. The populations within the Savanna phytophysiognomy showed values above average for six of the eight evaluated genetic diversity parameters. Using this classification based on phytophysiognomy demonstrated a high predictive power for genetic differentiation in P. reticulata. Furthermore, the interplay of climate, soil and geographic distance influenced the spread of alleles across the landscape. Based on our findings, we propose seed translocation, taking into account the biome, with restricted use of seed sources acquired or collected from the same environment as the areas to be restored (Savanna or Atlantic Forest).

Biodiversity loss reduces global terrestrial carbon storage

Natural ecosystems store large amounts of carbon globally, as organisms absorb carbon from the atmosphere to build large, long-lasting, or slow-decaying structures such as tree bark or root systems. An ecosystem's carbon sequestration potential is tightly linked to its biological diversity. Yet when considering future projections, many carbon sequestration models fail to account for the role biodiversity plays in carbon storage. Here, we assess the consequences of plant biodiversity loss for carbon storage under multiple climate and land-use change scenarios. We link a macroecological model projecting changes in vascular plant richness under different scenarios with empirical data on relationships between biodiversity and biomass. We find that biodiversity declines from climate and land use change could lead to a global loss of between 7.44-103.14 PgC (global sustainability scenario) and 10.87-145.95 PgC (fossil-fueled development scenario). This indicates a self-reinforcing feedback loop, where higher levels of climate change lead to greater biodiversity loss, which in turn leads to greater carbon emissions and ultimately more climate change. Conversely, biodiversity conservation and restoration can help achieve climate change mitigation goals.

Anthropogenic vs. natural habitats: Higher microbial biodiversity pays the trade-off of lower connectivity

Climate change and anthropogenic disturbances are known to influence soil biodiversity. The objectives of this study were to compare the community composition, species coexistence patterns, and ecological assembly processes of soil microbial communities in a paired setting featuring a natural and an anthropogenic ecosystem facing each other at identical climatic, pedological, and vegetational conditions. A transect gradient from forest to seashore allowed for sampling across different habitats within both sites. The field survey was carried out at two adjacent strips of land within the Po River delta lagoon system (Veneto, Italy) one of which is protected within a natural preserve and the other has been converted for decades into a tourist resort. The anthropogenic pressure interestingly led to an increase in the α-diversity of soil microbes but was accompanied by a reduction in β-diversity. The community assembly mechanisms of microbial communities differentiate in natural and anthropic ecosystems: for bacteria, in natural ecosystems deterministic variables and homogeneous selection play a main role (51.92%), while stochastic dispersal limitation (52.15%) is critical in anthropized ecosystems; for fungi, stochastic dispersal limitation increases from 38.1% to 66.09% passing from natural to anthropized ecosystems. We are on calcareous sandy soils and in more natural ecosystems a variation of topsoil pH favors the deterministic selection of bacterial communities, while a divergence of K availability favors stochastic selection. In more anthropized ecosystems, the deterministic variable selection is influenced by the values of SOC. Microbial networks in the natural system exhibited higher numbers of nodes and network edges, as well as higher averages of path length, weighted degree, clustering coefficient, and density than its equivalent sites in the more anthropically impacted environment. The latter on the other hand presented a stronger modularity. Although the influence of stochastic processes increases in anthropized habitats, niche-based selection also proves to impose constraints on communities. Overall, the functionality of the relationships between groups of microorganisms co-existing in communities appeared more relevant to the concept of functional biodiversity in comparison to the plain number of their different taxa. Fewer but functionally more organized lineages displayed traits underscoring a better use of the resources than higher absolute numbers of taxa when those are not equally interconnected in their habitat exploitation. However, considering that network complexity can have important implications for microbial stability and ecosystem multifunctionality, the extinction of complex ecological interactions in anthropogenic habitats may impair important ecosystem services that soils provide us.

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.

Plant diversity increases spatial stability of aboveground productivity in alpine grasslands

Plant diversity can significantly affect the grassland productivity and its stability. However, it remains unclear how plant diversity affects the spatial stability of natural grassland productivity, especially in alpine regions that are sensitive to climate change. We analyzed the interaction between plant (species richness and productivity, etc.) and climatic factors (precipitation, temperature, and moisture index, etc.) of alpine natural grassland on the Qinghai-Tibetan Plateau. In addition, we tested the relationship between plant diversity and spatial stability of grassland productivity. Results showed that an increase in plant diversity significantly enhanced community productivity and its standard deviation, while reducing the coefficient of variation in productivity. The influence of plant diversity on productivity and the reciprocal of productivity variability coefficient was not affected by vegetation types. The absolute values of the regression slopes between climate factors and productivity in alpine meadow communities with higher plant diversity were smaller than those in alpine meadow communities with lower plant diversity. In other words, alpine meadow communities with higher plant diversity exhibited a weaker response to climatic factors in terms of productivity, whereas those with lower plant diversity showed a stronger response. Our results indicate that high plant diversity buffers the impact of ambient pressure (e.g., precipitation, temperature) on alpine meadow productivity, and significantly enhanced the spatial stability of grassland productivity. This finding provides a theoretical basis for maintaining the stability of grassland ecosystems and scientifically managing alpine grasslands under the continuous climate change.

Biodiversity modeling advances will improve predictions of nature's contributions to people

Accurate predictions of ecosystem functions and nature's contributions to people (NCP) are needed to prioritize environmental protection and restoration in the Anthropocene. However, our ability to predict NCP is undermined by approaches that rely on biophysical variables and ignore those describing biodiversity, which have strong links to NCP. To foster predictive mapping of NCP, we should harness the latest methods in biodiversity modeling. This field advances rapidly, and new techniques with promising applications for predicting NCP are still underutilized. Here, we argue that employing recent advances in biodiversity modeling can enhance the accuracy and scope of NCP maps and predictions. This enhancement will contribute significantly to the achievement of global objectives to preserve NCP, for both the present and an unpredictable future.

Wetland habitats supporting waterbird diversity: Conservation perspective on biodiversity-ecosystem functioning relationship

Wetlands, as core habitats for supporting waterbird diversity, provide a variety of ecosystem services through diverse ecosystem functioning. Wetland degradation and wetland-habitat loss undermine the relationship between biodiversity-ecosystem functioning (BEF), affecting the diversity of habitats and waterbirds. The conservation of waterbird diversity is closely linked to the proper functioning of wetland ecosystems (nutrient cycling, energy storage, and productivity). Waterbirds have complex habitat preferences and sensitivities, which affect biotic interactions. By highlighting the importance of temporal and spatial scales guided by BEF, a habitat-waterbird conservation framework is presented (BEF relationships are described at three levels: habitat, primary producers, and waterbird diversity). We present a novel perspective on habitat conservation for waterbirds by incorporating research on the effects of biodiversity and ecosystem functioning to address the crucial challenges in global waterbird diversity loss, ecosystem degradation, and habitat conservation. Last, it is imperative to prioritize strategies of habitat protection with the incorporation of BEF for future waterbird conservation.

Species distribution models to predict the impacts of environmental disasters on shrimp species of economic interest

Here, we used distribution models to predict the size of the environmentally suitable area for shrimps of fishing interest that were impacted by the tailing plume from the collapse of the Fundão Dam, one of the largest ecological disasters ever to occur in Brazil. Species distribution models (SDMs) were generated for nine species of penaeid shrimp that occurred in the impacted region. Average temperature showed the highest percentage of contribution for SDMs. The environmental suitability of penaeids varied significantly in relation to the distance to the coast and mouth river. The area of environmental suitability of shrimps impacted by tailings plumes ranged from 27 to 47 %. Notably, three protected areas displayed suitable conditions, before the disaster, for until eight species. The results obtained by the SDMs approach provide crucial information for conservation and restoration efforts of coastal biodiversity in an impacted region with limited prior knowledge about biodiversity distribution.

The north-south divide? Macroalgal functional trait diversity and redundancy varies with intertidal aspect

BACKGROUND AND AIMS

Marine macroalgae ('seaweeds') are critical to coastal ecosystem structure and function, but also vulnerable to the many environmental changes associated with anthropogenic climate change (ACC). The local habitat conditions underpinning observed and predicted ACC-driven changes in intertidal macroalgal communities are complex and probably site-specific and operate in addition to more commonly reported regional factors such as sea surface temperatures.

METHODS

We examined how the composition and functional trait expression of macroalgal communities in SW England varied with aspect (i.e. north-south orientation) at four sites with opposing Equator- (EF) and Pole-facing (PF) surfaces. Previous work at these sites had established that average annual (low tide) temperatures vary by 1.6 °C and that EF-surfaces experience six-fold more frequent extremes (i.e. >30 °C).

KEY RESULTS

PF macroalgal communities were consistently more taxon rich; 11 taxa were unique to PF habitats, with only one restricted to EF. Likewise, functional richness and dispersion were greater on PF-surfaces (dominated by algae with traits linked to rapid resource capture and utilization, but low desiccation tolerance), although differences in both taxon and functional richness were probably driven by the fact that less diverse EF-surfaces were dominated by desiccation-tolerant fucoids.

CONCLUSIONS

Although we cannot disentangle the influence of temperature variation on algal ecophysiology from the indirect effects of aspect on species interactions (niche pre-emption, competition, grazing, etc.), our study system provides an excellent model for understanding how environmental variation at local scales affects community composition and functioning. By virtue of enhanced taxonomic diversity, PF-aspects supported higher functional diversity and, consequently, greater effective functional redundancy. These differences may imbue PF-aspects with resilience against environmental perturbation, but if predicted increases in global temperatures are realized, some PF-sites may shift to a depauperate, desiccation-tolerant seaweed community with a concomitant loss of functional diversity and redundancy.

Testing alternative hypotheses for the decline of cichlid fish in Lake Victoria using fish tooth time series from sediment cores

Lake Victoria is well known for its high diversity of endemic fish species and provides livelihoods for millions of people. The lake garnered widespread attention during the twentieth century as major environmental and ecological changes modified the fish community with the extinction of approximately 40% of endemic cichlid species by the 1980s. Suggested causal factors include anthropogenic eutrophication, fishing, and introduced non-native species but their relative importance remains unresolved, partly because monitoring data started in the 1970s when changes were already underway. Here, for the first time, we reconstruct two time series, covering the last approximately 200 years, of fish assemblage using fish teeth preserved in lake sediments. Two sediment cores from the Mwanza Gulf of Lake Victoria, were subsampled continuously at an intra-decadal resolution, and teeth were identified to major taxa: Cyprinoidea, Haplochromini, Mochokidae and Oreochromini. None of the fossils could be confidently assigned to non-native Nile perch. Our data show significant decreases in haplochromine and oreochromine cichlid fish abundances that began long before the arrival of Nile perch. Cyprinoids, on the other hand, have generally been increasing. Our study is the first to reconstruct a time series of any fish assemblage in Lake Victoria extending deeper back in time than the past 50 years, helping shed light on the processes underlying Lake Victoria's biodiversity loss.

The importance of worldwide linguistic and cultural diversity for climate change resilience

Local minority languages and dialects, through the local knowledge and expertise associated with them, can play major roles in analysing climate change and biodiversity loss, in facilitating community awareness of environmental crises and in setting up locally-adapted resilience and sustainability strategies. While the situation and contribution of Indigenous and Tribal Peoples are of emblematic importance, the issue of the relationships between cultural and linguistic diversity and environmental awareness and protection does not solely concern peripheral highly-specialized communities in specific ecosystems of the Global South, but constitutes a worldwide challenge, throughout all of the countries, whatever their geographical location, their economical development, or their political status. Environmental emergency and climate change resilience should therefore raise international awareness on the need to promote the survival and development of minority languages and dialects and to take into account their creativity and expertise in relation to the dynamics of their local environments.

The loss of plant functional groups increased arthropod diversity in an alpine meadow on the Tibetan Plateau

Plant species loss, driven by global changes and human activities, can have cascading effects on other trophic levels, such as arthropods, and alter the multitrophic structure of ecosystems. While the relationship between plant diversity and arthropod communities has been well-documented, few studies have explored the effects of species composition variation or plant functional groups. In this study, we conducted a long-term plant removal experiment to investigate the impact of plant functional group loss (specifically targeting tall grasses and sedges, as well as tall or short forbs) on arthropod diversity and their functional groups. Our findings revealed that the removal of plant functional groups resulted in increased arthropod richness, abundance and the exponential of Shannon entropy, contrary to the commonly observed positive correlation between plant diversity and consumer diversity. Furthermore, the removal of different plant groups had varying impacts on arthropod trophic levels. The removal of forbs had a more pronounced impact on herbivores compared to graminoids, but this impact did not consistently cascade to higher-trophic arthropods. Notably, the removal of short forbs had a more significant impact on predators, as evidenced by the increased richness, abundance, the exponential of Shannon entropy, inverse Simpson index and inverse Berger-Parker index of carnivores and abundance of omnivores, likely attributable to distinct underlying mechanisms. Our results highlight the importance of plant species identity in shaping arthropod communities in alpine grasslands. This study emphasizes the crucial role of high plant species diversity in controlling arthropods in natural grasslands, particularly in the context of plant diversity loss caused by global changes and human activities.

Recent progress on phytoremediation of urban air pollution

The rapid growth of population and economy has led to an increase in urban air pollutants, greenhouse gases, energy shortages, environmental degradation, and species extinction, all of which affect ecosystems, biodiversity, and human health. Atmospheric pollution sources are divided into direct and indirect pollutants. Through analysis of the sources of pollutants, the self-functioning of different plants can be utilized to purify the air quality more effectively. Here, we explore the absorption of greenhouse gases and particulate matter in cities as well as the reduction of urban temperatures by plants based on international scientific literature on plant air pollution mitigation, according to the adsorption, dust retention, and transpiration functions of plants. At the same time, it can also reduce the occurrence of extreme weather. It is necessary to select suitable tree species for planting according to different plant functions and environmental needs. In the context of tight urban land use, the combination of vertical greening and urban architecture, through the rational use of plants, has comprehensively addressed urban air pollution. In the future, in urban construction, attention should be paid to the use of heavy plants and the protection and development of green spaces. Our review provides necessary references for future urban planning and research.

Genome-wide association study, population structure, and genetic diversity of the tea plant in Guizhou Plateau

BACKGROUND

Guizhou Plateau, as one of the original centers of tea plant, has a profound multi-ethnic cultural heritage and abundant tea germplasm resources. However, the impact of indigenous community factors on the genetic diversity, population structure and geographical distribution of tea plant is still unclear.

RESULTS

Using the genotyping-by-sequencing (GBS) approach, we collected 415 tea plant accessions from the study sites, estimated genetic diversity, developed a core collection, and conducted a genome-wide association study (GWAS) based on 99,363 high-quality single-nucleotide polymorphisms (SNPs). A total of 415 tea accessions were clustered into six populations (GP01, GP02, GP03, GP04, GP05 and GP06), and the results showed that GP04 and GP05 had the highest and lowest genetic diversity (Pi = 0.214 and Pi = 0.145, respectively). Moreover, 136 tea accessions (33%) were selected to construct the core set that can represent the genetic diversity of the whole collection. By analyzing seven significant SNP markers associated with the traits such as the germination period of one bud and two leaves (OTL) and the germination period of one bud and three leaves (OtL), four candidate genes possibly related to OTL and OtL were identified.

CONCLUSIONS

This study revealed the impact of indigenous communities on the population structure of 415 tea accessions, indicating the importance of cultural practices for protection and utilization of tea plant genetic resources. Four potential candidate genes associated with the OTL and OtL of tea plant were also identified, which will facilitate genetic research, germplasm conservation, and breeding.

The chromosome-scale genome of Magnolia sinica (Magnoliaceae) provides insights into the conservation of plant species with extremely small populations (PSESP)

Magnolia sinica (Magnoliaceae) is a highly threatened tree endemic to southeast Yunnan, China. In this study, we generated for the first time a high-quality chromosome-scale genome sequence from M. sinica, by combining Illumina and ONT data with Hi-C scaffolding methods. The final assembled genome size of M. sinica was 1.84 Gb, with a contig N50 of ca. 45 Mb and scaffold N50 of 92 Mb. Identified repeats constituted approximately 57% of the genome, and 43,473 protein-coding genes were predicted. Phylogenetic analysis shows that the magnolias form a sister clade with the eudicots and the order Ceratophyllales, while the monocots are sister to the other core angiosperms. In our study, a total of 21 individuals from the 5 remnant populations of M. sinica, as well as 22 specimens belonging to 8 related Magnoliaceae species, were resequenced. The results showed that M. sinica had higher genetic diversity (θw = 0.01126 and θπ = 0.01158) than other related species in the Magnoliaceae. However, population structure analysis suggested that the genetic differentiation among the 5 M. sinica populations was very low. Analyses of the demographic history of the species using different models consistently revealed that 2 bottleneck events occurred. The contemporary effective population size of M. sinica was estimated to be 10.9. The different patterns of genetic loads (inbreeding and numbers of deleterious mutations) suggested constructive strategies for the conservation of these 5 different populations of M. sinica. Overall, this high-quality genome will be a valuable genomic resource for conservation of M. sinica.

Land abandonment transforms soil microbiome stability and functional profiles in apple orchards of the Chinese Losses Plateau

Land abandonment is considered an effective strategy for ecological restoration on a global scale. However, few studies have focused on how environmental heterogeneity associated with the age of land abandonment affects the assembly and potential functions of the soil microbial community. In the present study, we investigated the community assembly of soil bacteria and fungi as well as the stability of soil networks and their potential functions in the chronosequence of abandoned apple orchards. We elucidated that the Shannon diversity of bacteria and the richness of fungi increased as land abandonment progressed. In addition, land abandonment destabilized the microbial network stability but increased network complexity. Soil available nitrogen, total carbon, and moisture are the potentially important factors in shaping the soil microbial assembly. Importantly, we showed that the microbial community diversity and functional diversity presented a synchronization effect in response to the different stages of land abandonment. Furthermore, specific bacterial taxa related to carbon fixation, dissimilatory nitrate reduction, and organic phosphorus mineralization were significantly enriched during the early abandonment stage. Collectively, these results indicate that land abandonment significantly transformed soil microbiome assembly and functional adaptation during the restoration process. These findings provide valuable insights into the influence of ecological restoration on soil microbiome and ecosystem functions in arable areas.

Effects of agricultural land use on soil nutrients and its variation along altitude gradients in the downstream of the Yarlung Zangbo River Basin, Tibetan Plateau

Agricultural development in alpine ecosystems can cause significant changes in soil nutrients. With large altitude spans, the combined effect of the two is still unclear in existing research. To answer this problem, this study took the downstream of the Yarlung Zangbo River Basin (YZRB) as the study area, and designed a comparative soil sampling scheme along the altitude gradient. We compared soil nutrient characteristics facility agricultural land (FA) and field cultivated land (FC), using grassland (GL), the main source of agriculture expansion, as a reference. A total of 44 sampling areas were designed within an altitude range of 800-3500 m to reveal the effects of agricultural land development along the altitude gradient on soil nutrients. Research found that the FA significantly improved soil nutrient levels, with most nutrient indicators higher than those of FC and GL (P < 0.05), while the above indicators of FC were only slightly higher than GL. Moreover, the effects of agricultural development decreased with soil depth, and mainly occurred within the 0-30 cm soil layer (P < 0.05). With increasing altitude, most of soil nutrients first decreased and then increased and differences in soil nutrients among different land use modes first expanded and then shrank. This may be related to differences in farmland management methods, vegetation coverage, and temperature under different altitude gradient constraints. Especially in middle-altitude areas, the FA not only breaks through the low-temperature limitations of the plateau, but also has the advantage of large-scale development, which is suggested for future agricultural intensification in the plateau.

Influence of Ecological Multiparameters on Facets of β-Diversity of Freshwater Plankton Ciliates

Understanding the relative importance of the factors that drive global patterns of biodiversity is among the major topics of ecological and biogeographic research. In freshwater bodies, spatial, temporal, abiotic, and biotic factors are important structurers of these ecosystems and can trigger distinct responses according to the facet of biodiversity considered. The objective was to evaluate how different facets of β-diversity (taxonomic, functional, and phylogenetic) based on data from the planktonic ciliate community of a Neotropical floodplain, are influenced by temporal, spatial, abiotic, and biotic factors. The research was conducted in the upper Paraná River floodplain between the years 2010 and 2020 in different water bodies. All predictors showed significant importance on the facets of β-diversity, except the abiotic predictors on species composition data, for the taxonomic facet. The functional and phylogenetic facets were mostly influenced by abiotic, biotic, and spatial factors. For temporal predictors, results showed influence on taxonomic (structure and composition data) and functional (structure data) facets. Also, a fraction of shared explanation between the temporal and abiotic components was observed for the distinct facets. Significant declines in β-diversity in continental ecosystems have been evidenced, especially those with drastic implications for ecosystemic services. Therefore, the preservation of a high level of diversity in water bodies, also involving phylogenetic and functional facets, should be a priority in conservation plans and goals, to ensure the maintenance of important ecological processes involving ciliates.

Optimizing cropping systems to close the gap between economic profitability and environmental health

Supporting food security while maintaining ecosystem sustainability is one of the most important global challenges for humanity. Optimization of cropping systems is expected to promote the ecosystem services of agroecosystems. Yet, how and why cropping system influences the trade-offs between economic profitability and multiple ecosystem services remain poorly understood. We investigate the influence of six cropping systems on trade-offs between economic profitability and multiple ecosystem services after considering 36 agricultural ecosystem properties using field experiment data from 2020 to 2022. We show that designing cropping system is a critical tool to closing the gap between ecosystem sustainability and commercial profitability. Cropping system with three harvests within 2 yr had higher performance in overall ecosystem multiple services through enhancement of supporting, regulating, and economic performance without compromising provisioning compared with four other systems. These systems diminished the trade-off among multiple services, resulting in a 'win-win' situation for economics and multiple services. By contrast, the monoculture and double cropping systems lead to a strong trade-off between pairwise services including ecosystem health and profitability. Our work illustrates the substantial potential of rotation systems with three harvests within 2 yr in enforcing ecosystem services and closing the trade-offs among multiple agricultural ecosystem services.

Environmental filtering and biotic interactions act on different facets of the diversity of benthic assemblages associated with eelgrass

Eelgrass supports diverse benthic communities that ensure a variety of ecosystem functions. To better understand the ecological processes that shape community composition in eelgrass at local and regional scales, taxonomic and functional α- and β-diversity were quantified for communities inhabiting five meadows in France. The extent to which environmental factors affected local and regional benthic communities was quantified by considering their direct and indirect effects (through morphological traits of eelgrass) using piecewise structural equation modeling (pSEM). Communities supported by eelgrass had higher species abundances, as well as taxonomic and functional diversity compared to nearby bare sediments. No significant differences were found between communities from the center relative to the edges of meadows, indicating that both habitats provide similar benefits to biodiversity. The presence of a few abundant species and traits suggests moderate levels of habitat filtering and close associations of certain species with eelgrass. Nevertheless, high turnover of a large number of rare species and traits was observed among meadows, resulting in meadows being characterized by their own distinct communities. High turnover indicates that much of the community is not specific to eelgrass, but rather reflects local species pools. pSEM showed that spatial variation in community composition (β-diversity) was primarily affected by environmental conditions, with temperature, current velocity, and tidal amplitude being the most significant explanatory variables. Local richness and abundance (α-diversity) were affected by both environment and morphological traits. Importantly, morphological traits of Zostera marina were also influenced by environmental conditions, revealing cascading effects of the environment on assemblages. In sum, the environment exerted large effects on community structure at both regional and local scales, while plant traits were only pertinent in explaining local diversity. This complex interplay of processes acting at multiple scales with indirect effects should be accounted for in conservation efforts that target the protection of biodiversity.

Patterns of bacterial distance decay and community assembly in different land-use types as influenced by tillage management and soil layers

Land use and cover change are major factors driving global change and greatly impact terrestrial organisms, especially soil microbial diversity. Little is known, however, about bacterial diversity, distribution patterns and assembly processes across different land use types. In this study, therefore, we conducted a large-scale field survey of 48 sampling sites, encompassing different land use types in Xuancheng city, China, with different degrees of soil disturbance and different soil horizons. The distance-decay relationships (DDRs), assembly processes and the spatial patterns of soil bacterial communities were investigated based on high-throughput sequencing data. We found that the DDRs might be weakened by anthropogenic disturbances, which were not observed in tilled soils, while a decreasing trend was observed along the soil horizon in untilled soils. The relative importance of environmental factors and geographic distance varied with soil tillage. Specifically, bacterial communities in tilled soils were driven by non-spatially autocorrelated environmental factors, while untilled soils were more susceptible to geographic distance. In addition, the heterogeneity of soil properties, as well as the differences in soil bacterial niche width and niche overlap, determined the assembly processes of the bacterial community, resulting in opposite trends along the soil layers in tilled and untilled soils. These findings expand the current understanding of the biogeography of soil bacterial communities across different land use types.

Impacts of landscape patterns on plant species diversity at a global scale

Landscape patterns are important drivers of biodiversity. Owing to differences in vegetation types, sampling methods, diversity measures, spatial scales, and landscape levels, the impact of landscape patterns on biodiversity remains widely debated. Using a global standardized plant community database and land use and land cover maps at 30-m resolution, for the period 1990-2017, we calculated plant species α- and β-diversity, and landscape metrics at patch- and landscape-levels, and discerned the direct and indirect impacts of landscape patterns on plant species diversity based on environmental factors, namely climate, spatial features, and human disturbance. We found that landscape patterns exhibited the main indirect effects, whereas climate factors exhibited dominant direct effects on plant α-diversity via the direct effects of patch patterns and functional traits. With respect to β-diversity, landscape-level patterns exerted more direct than indirect effects. These effects are strongly dependent on scale. Landscape- and patch-level patterns had opposite effects on plant diversity, depending on their composition and spatial structure, demonstrating that their effects could be mediated by one another. The adaptation of plants to landscape patterns is mainly through variations in leaf area, plant height, specific leaf area, stem density, seed biomass, and other seed-dispersal traits, which vary across vegetation types. Our findings highlight the importance of functional traits and diversity in understanding the mechanism by which landscape patterns influence plant species diversity; accordingly, we recommend balancing the spatial structure of patch- and landscape-level patterns to enhance variation in functional traits, and, ultimately, to maintain global plant diversity.

Characterizing the Gut Microbial Communities of Native and Invasive Freshwater Bivalves after Long-Term Sample Preservation

Freshwater mussels are important indicators of the overall health of their environment but have suffered declines that have been attributed to factors such as habitat degradation, a loss of fish hosts, climate change, and excessive nutrient inputs. The loss of mussel biodiversity can negatively impact freshwater ecosystems such that understanding the mussel's gut microbiome has been identified as a priority topic for developing conservation strategies. In this study, we determine whether ethanol-stored specimens of freshwater mussels can yield representative information about their gut microbiomes such that changes in the microbiome through time could potentially be determined from museum mussel collections. A short-term preservation experiment using the invasive clam Corbicula fluminea was used to validate the use of ethanol as a method for storing the bivalve microbiome, and the gut microbiomes of nine native mussel species that had been preserved in ethanol for between 2 and 9 years were assessed. We show that ethanol preservation is a valid storage method for bivalve specimens in terms of maintaining an effective sequencing depth and the richness of their gut bacterial assemblages and provide further insight into the gut microbiomes of the invasive clam C. fluminea and nine species of native mussels. From this, we identify a "core" genus of bacteria (Romboutsia) that is potentially common to all freshwater bivalve species studied. These findings support the potential use of ethanol-preserved museum specimens to examine patterns in the gut microbiomes of freshwater mussels over long periods.

Positive effects of tree diversity on tropical forest restoration in a field-scale experiment

Experiments under controlled conditions have established that ecosystem functioning is generally positively related to levels of biodiversity, but it is unclear how widespread these effects are in real-world settings and whether they can be harnessed for ecosystem restoration. We used remote-sensing data from the first decade of a long-term, field-scale tropical restoration experiment initiated in 2002 to test how the diversity of planted trees affected recovery of a 500-ha area of selectively logged forest measured using multiple sources of satellite data. Replanting using species-rich mixtures of tree seedlings with higher phylogenetic and functional diversity accelerated restoration of remotely sensed estimates of aboveground biomass, canopy cover, and leaf area index. Our results are consistent with a positive relationship between biodiversity and ecosystem functioning in the lowland dipterocarp rainforests of SE Asia and demonstrate that using diverse mixtures of species can enhance their initial recovery after logging.

Diversified farms bolster forest-bird populations despite ongoing declines in tropical forests

While some agricultural landscapes can support wildlife in the short term, it is uncertain how well they can truly sustain wildlife populations. To compare population trends in different production systems, we sampled birds along 48 transects in mature forests, diversified farms, and intensive farms across Costa Rica from 2000 to 2017. To assess how land use influenced population trends in the 349 resident and 80 migratory species with sufficient data, we developed population models. We found, first, that 23% of species were stable in all three land use types, with the rest almost evenly split between increasing and decreasing populations. Second, in forest habitats, a slightly higher fraction was declining: 62% of the 164 species undergoing long-term population changes; nearly half of these declines occurred in forest-affiliated invertivores. Third, in diversified farms, 49% of the 230 species with population changes were declining, with 60% of these declines occurring in agriculture-affiliated species. In contrast, 51% of the species with population changes on diversified farms showed increases, primarily in forest-affiliated invertivores and frugivores. In intensive farms, 153 species showed population changes, also with similar proportions of species increasing (50%) and decreasing (50%). Declines were concentrated in agriculture-affiliated invertivores and forest-affiliated frugivores; increases occurred in many large, omnivorous species. Our findings paint a complex picture but clearly indicate that diversified farming helps sustain populations of diverse, forest-affiliated species. Despite not fully offsetting losses in forest habitats, diversified farming practices help sustain wildlife in a critical time, before possible transformation to nature-positive policies and practices.