搜索结果：Biodiversity

Tropical areas, particularly Brazil, are home to a significant portion of the world's biodiversity, with the Brazilian Atlantic Forest (BAF) being a crucial biome recognized as a global biodiversity hotspot. However, the BAF has been subject to severe degradation due to anthropogenic activities, resulting in extensive habitat loss and fragmentation. These changes have prompted numerous studies on their effects on biodiversity, focusing on forest fragments and protected areas. Despite this research, there is a notable lack of meta-data on biodiversity in human-modified landscapes within the BAF- where only 31% of the land remains as native forest. Most of the biome has been transformed by human activities, primarily for pasture and agriculture. By recognizing these knowledge gaps, researchers have begun investigating biodiversity in anthropogenically altered landscapes, to better understand species' responses to human-induced changes and inform conservation policies. A comprehensive literature search was conducted to answer the following primary question: "What is the diversity of birds and mammal species in agricultural fields and their adjacent areas of natural vegetation?" We aimed to address this question by creating a systematic map summarizing current knowledge about avian and mammalian species' presence in the BAF's agricultural matrix. This research also aimed (i) to identify common species in agricultural landscapes, (ii) to compare species richness in-crop (inside the agricultural field) and off-crop (non-cultivated areas outside the agricultural field), (iii) to determine crops with high species visitation, and (iv) to highlight areas for future research. We conducted a systematic literature map on bird and mammal biodiversity in agricultural landscapes within the BAF and adjacent natural vegetation areas. The search covered Web of Knowledge, Scopus, the National Library of Medicine, and the "Biblioteca Digital Brasileira" (Brazilian Digital Library) database for grey literature (dissertations and theses). Citation records were surveyed based on predefined criteria through title/abstract screening and full-text analysis. Eligible publications were used for meta-data coding and systematic map construction. Our systematic map identified 207 eligible publications included in the final evidence base. Research effort was distributed across taxonomic groups, with 78 studies focusing on birds, 126 on non-flying mammals (NFM), and 22 on bats. The most frequently studied agricultural systems were pasture and eucalyptus, followed by sugarcane, coffee, cacao, rubber tree, pinus, grape, araucaria, and corn. Extracted meta-data showed that studies reported species occurrences in both agricultural fields and adjacent natural areas. The map revealed significant knowledge clusters and gaps, particularly regarding the distribution of research across different crop types and the inclusion of species with varying conservation statuses. This systematic map identifies 846 species across 48 crop types in BAF agricultural landscapes, potentially indicating their use by wildlife; however, further quantitative synthesis is necessary to assess the relative importance of these areas. By mapping knowledge clusters and gaps-such as underrepresented regions and specific crop-taxa associations-this work provides a foundation for future systematic reviews and informs the development of more targeted environmental risk assessments and conservation policies.

Livestock grazing is the most widespread management tool for sustaining grassland biodiversity worldwide. Studying grazing effects on the vegetation composition is quite frequent, research on its effects onthe biodiversity and density of soil seed banks is scarce. We studied the effects of livestock type (e.g., sheep or cattle) and grazing intensity on the soil seed bank of species-rich sand grasslands. Altogether 25 grazed grasslands classified into four grazing intensity categories were studied; and their soil seed bank was analysed. We tested the following hypotheses: i) Diversity and density of soil seed banks are lower in sheep-grazed sites than in cattle-grazed ones. ii) Species composition, diversity, and density of the soil seed banks are more strongly affected by grazing intensity than by the livestock type. We found that sheep grazing sustained a much lower density of total seed bank regardless to grazing intensity. Livestock type mainly affected the seed bank density, while grazing intensity had a major significant effect on most of the variables. Most of the studied variables were affected by the interaction of grazing intensity and livestock type. We emphasise that i) livestock type must be carefully selected and high-intensity sheep grazing should be avoided in the long-run, and ii) for a sustainable grazing management and to meet nature conservation goals, grazing intensity and livestock type should be considered simultaneously.

Current understanding of how multiple stressors shape freshwater biodiversity at continental scales relies heavily on evidence from postindustrial temperate regions, potentially misrepresenting the dynamics of ecosystems facing rapid development and extreme environmental heterogeneity. Here, we present a standardized, continental-scale field survey of benthic macroinvertebrates across 502 sites in China to test the universality of established macroecological patterns. Contrary to the expectation that physical habitat and climatic gradients primarily drive community structure, we found that organic pollution, with a focus on oxygen-demand assays (COD and BOD), emerged as the single most influential variable, explaining the largest proportion of variation in taxonomic, functional, and phylogenetic diversity. Together with total nitrogen and total phosphorus loading, this chemical pressure largely overrode the explanatory contribution of land-use and climatic drivers, with stressor interactions characterized by asymmetric dominance rather than the synergistic amplification commonly predicted. Furthermore, despite steep environmental gradients that theoretically favor deterministic sorting, community assembly was overwhelmingly dominated by stochastic processes ( ∼ $$ \sim $$ 86%, based on overall pairwise comparisons across all sites). We suggest this pattern is consistent with a "stochastic trap" hypothesis, potentially arising from high-frequency anthropogenic disturbances that weaken trait-environment matching. These findings indicate that biodiversity frameworks derived from stabilized, temperate systems may not generalize to the compressed modernity of developing regions. We propose that global conservation strategies should consider prioritizing the reduction of chemical bottlenecks, which may act as critical physiological constraints on freshwater resilience in the Anthropocene.

Unclear species boundaries are a common challenge in ecological studies and species inventories, obscuring patterns of biodiversity and complicating inferences about ecological and evolutionary processes. One possible cause of fuzziness is hybridisation, but little information exists on hybridisation in the tropics. Here we aim to address the question of potential hybridisation in the tropical American fern genus Trichomanes (Hymenophyllaceae) and to clarify evolutionary relationships within the genus. We take advantage of nuclear target-capture sequencing, haplotype phasing and off-target plastid reads to detect phylogenetic relationships and reticulate histories. We sampled 303 individuals that represent 41 known Trichomanes species. Our analyses recovered a robust backbone for the genus, strongly supporting subgenus Trichomanes as sister to subgen. Feea, and subgen. Davalliopsis as sister to subgen. Lacostea. Trichomanes pinnatum proved to be a complex where six different unnamed morphs represent four different kinds of evolutionary history. Two morphs appear to be stabilised, relatively old hybrid-derived species, one represents a recent hybrid, one reflects repeated spontaneous hybridisation between the same parent species, and one represents within-species morphological variation without any obvious genomic signal. Excluding the four hybrids makes T. pinnatum s.s. morphologically and genetically much more uniform, but its geographic distribution still covers practically all tropical America, indicating that the species may be approaching panmixia.

The large-scale construction of cascade dams worldwide has profoundly altered river hydrological regimes and habitats, producing significant threats to fish diversity. This study integrated environmental DNA (eDNA) and traditional fishing data to construct a fish dataset from the middle and upper reaches of the Jinsha River (2003-2024). It was used to systematically reveal the spatiotemporal patterns of fish diversity and analyze key environmental drivers. Additionally, the Isolation Forest algorithm was employed to remove 29 outliers from the historical data. Distance-based redundancy analysis showed that flow velocity was the strongest environmental driver for species composition (R2 = 0.51, p = 0.005) and functional composition (R2 = 0.41, p = 0.018). This suggests that flow velocity reduction, closely associated with cascade dam construction, may act as an important agent of environmental filtering. β-diversity analysis revealed that local-scale functional nestedness (β-nes: 37.4%) and a directional functional shift toward resident and limnophilic groups suggest incipient functional homogenization in the cascade dam system, although temporal evidence was lacking due to staggered dam construction. Notably, although species richness increased, functional evenness (FEve) declined significantly, revealing an imbalanced functional diversity despite higher taxonomic diversity. These findings enhance our understanding of the long-term ecological impacts of cascade dams and provide a scientific basis for mitigating incipient biodiversity homogenization induced by hydropower development.

Unsustainable dietary patterns contribute substantially to climate change, biodiversity loss, and the growing global burden of non-communicable diseases. University years represent a critical transitional period during which lifelong eating behaviors are shaped. Understanding whether positive attitudes toward healthy eating are associated with sustainable dietary behaviors may inform integrated public health strategies targeting both health and environmental outcomes. This study examined the relationship between healthy eating attitudes and sustainable nutrition behaviors among Turkish university students and explored associated demographic factors. A cross-sectional study was conducted between December 2023 and October 2024 among 610 university students aged 18-26 years. Data were collected using structured self-report questionnaires. Healthy eating attitudes were assessed using the Attitude Scale for Healthy Nutrition (ASHN), and sustainable dietary behaviors were measured using the Behaviors Scale Towards Sustainable Nutrition (BSSN). Non-parametric tests, Spearman correlation analysis, confirmatory factor analysis, and structural equation modelling (SEM) were performed. Participants demonstrated generally high levels of healthy eating attitudes. A weak but statistically significant positive correlation was observed between overall healthy eating attitudes and sustainable dietary behaviors (r&#x2009;=&#x2009;0.182, p&#x2009;<&#x2009;0.001). SEM indicated that healthy eating attitudes were positively associated with sustainable nutrition behaviors (&#x3b2;&#x2009;=&#x2009;0.542, p&#x2009;<&#x2009;0.001). Non-smokers and female students exhibited significantly higher sustainable nutrition behavior scores compared to smokers and male students (p&#x2009;<&#x2009;0.05). Healthy eating attitudes were positively associated with sustainable dietary behaviors among university students. Although the strength of the association was modest, the findings suggest that health-oriented attitudes may support environmentally responsible dietary practices. Public health interventions that integrate sustainability principles into university-based nutrition education and campus food policies may represent a promising strategy to advance both human and environmental health. Longitudinal studies are needed to clarify causal pathways.

The increasing prevalence of antifungal resistance necessitates the exploration of novel therapeutic agents from natural reservoirs. Bacteria derived from medicinal plants serve as an underexploited repository of biologically active secondary metabolites. This study investigated the chemical profile and antifungal potential of the cell-free supernatant (CFS) derived from Lactiplantibacillus plantarum (L. plantarum) strain isolated from the medicinal plant Pulicaria jaubertii (P. jaubertii) (Asteraceae) in Yemen. L. plantarum was isolated from surface-sterilized leaves of P. jaubertii and cultured to obtain CFSs. The chemical composition of the CFS was characterized using Fourier-transform infrared (FT-IR) spectroscopy. Antifungal efficacy was evaluated against clinically significant isolates of Aspergillus fumigatus (A. fumigatus) and Candida albicans (C. albicans) using agar incorporation and agar well-diffusion methods, respectively. FT-IR spectroscopy indicated that the CFS is a complex mixture containing functional groups of organic acids, peptides, and carbohydrates. It exhibited dose-dependent antifungal activity, achieving 71.9% and 90.0% growth inhibition against A. fumigatus and C. albicans, respectively, at 30% (v/v). Notably, a sharp increase in efficacy occurred between 20 and 25% (v/v). We hypothesize that this threshold effect may reflect a multi-mechanistic mode of action, potentially driven by the interplay between the acidic and peptidic constituents. These findings underscore the potential of L. plantarum CFS as a promising, sustainable source of multicomponent antifungal agents. This study highlights the value of integrating plant biodiversity with microbial chemistry to develop postbiotic interventions that address critical fungal challenges.

Climate change poses a significant threat to global biodiversity, altering species ranges and ecological dynamics. This study investigates the impact of climate change on Tabanus taeniola (Diptera: Tabanidae), a widely distributed horsefly with ecological importance in Africa and South America. Our objective was to model its current habitat suitability and predict future distribution shifts under various climatic scenarios. Using occurrence data from GBIF and and bioclimatic variables from WorldClim (BIO1-BIO19), we screened predictors for multicollinearity and calibrated MaxEnt models using a final subset of five variables. The model showed high accuracy, with an AUC of 0.918. Our findings identify the Minimum Temperature of the Coldest Month (BIO6) and Mean Temperature of Coldest Quarter (BIO11) as the key climatic drivers, with the species thriving in temperatures from 16&#xa0;&#xb0;C to 29&#xa0;&#xb0;C. Future projections, using the BCC-CSM2-MR and MRI-ESM2-0 models under SSP370 and SSP585 scenarios for 2050-2070, predict significant distributional shifts. We forecast a decline in optimal habitats in lowland tropical regions, with an expansion into temperate zones and higher altitudes in East Africa, South America, and parts of southern Europe. These projections indicate substantial redistribution toward higher elevations and temperate regions under future warming scenarios.

Ocean alkalinity enhancement (OAE) is proposed as a potential tool to remove atmospheric CO2 and mitigate climate change. However, the effects of OAE on marine protozoa remain poorly understood. In this study, we conducted acute and acclimated experiments on two heterotrophic nanoflagellates, i.e., Cafeteria burkhardae and Paraphysomonas longispina, to investigate their responses to two substances (NaHCO3 and NaOH) at low (set ~2,600 &#xb5;mol L-1) and high (set ~4,000 &#xb5;mol L-1) levels, respectively. Our results showed that the two species had similar negative reactions under acute exposure. However, the two species showed different tolerances after acclimation. The growth rates of C. burkhardae decreased under all OAE treatments, while its reactive oxygen species accumulated only at the high OAE level. The low-level OAE treatments had no significant effects, but high-level OAE was more adverse for P. longispina, which grew more slowly and grazed more, indicating lower growth efficiency. Underlying transcriptomic mechanisms were only analyzed for low-level OAE, which were consistent with the physiological responses. Replication and repair and metabolism-related pathways were significantly inhibited, with translation-related pathways stimulated in C. burkhardae. For P. longispina, in addition to translation-related pathways, replication and repair, and metabolism pathways were significantly upregulated. Overall, our findings suggest the potential negative effects of OAE on marine protozoa, and the effects can vary depending on the species, level, and substances. Given the critical role of protists in marine ecosystems, these adverse effects raise important concerns about the broader implications of OAE for marine biodiversity and ecosystem stability.IMPORTANCEOcean alkalinity enhancement (OAE) represents a novel approach to mitigate climate change by increasing the ocean's CO2 sequestration capacity. However, the potential ecological and environmental impacts of OAE on marine microorganisms, particularly protozoa, remain poorly understood. This study investigates the responses of two heterotrophic nanoflagellates, Cafeteria burkhardae and Paraphysomonas longispina, to varying levels of OAE treatments using NaHCO3 and NaOH. Our findings reveal significant species-specific differences in tolerance and physiological responses, with implications for microbial community dynamics in marine ecosystems. By employing transcriptomic analysis, we uncover the underlying molecular mechanisms. Ultimately, our study informs the development of sustainable ocean-based climate solutions, emphasizing the importance of considering microbial ecology in environmental management and policy.

The laboratory diagnosis of tick-borne infections is a&#xa0;major interdisciplinary issue, closely linked not only to advances in molecular biological methods but also to changes in ecosystems and biodiversity caused by climatic and anthropogenic factors. These factors significantly influence the epidemiological situation both globally and in the Czech Republic, where a&#xa0;marked increase in the incidence of serious tick-borne infections has been observed in recent years. Current diagnostic approaches combine indirect serological methods (e.g., ELISA, Western blot, and immunofluorescence assays) with direct molecular techniques such as PCR and RT-PCR. The choice of an appropriate method depends on the clinical stage of the disease, timing of sample collection, and the type of biological material used. Insufficient sensitivity in the early phases of infection and poorly timed sampling can lead to false-negative results. Despite the availability of a&#xa0;wide range of laboratory tools, the proportion of undiagnosed cases remains high, complicating not only clinical decision-making and treatment but also the assessment of the true prevalence of these infections and the planning of targeted epidemiological measures.

Predatory insects such as ladybirds, green lacewings, and an aphid midge have been commercialized and deployed worldwide to deal with the challenge of pest control. However, limited information is available on their associated viruses. To start filling this gap, this study employed an integrative bioinformatics approach with 21 publicly available RNA-seq libraries, from six countries, of eight natural enemy species used to control aphids. A total of 41 putative novel viruses were identified and classified into 16 families and 1 genus. In addition, 13 known viruses were detected, including aphid and phytopathogenic viruses, and a virus from the invasive harlequin ladybird (Harmonia axyridis). The Aphid lethal paralysis virus was the most common virus, detected in several species at different trophic levels, including plants, aphid vectors, and predatory insects, suggesting potential host sharing or dietary/environmental origin. In summary, this unique bioinformatic assessment of eight agriculturally significant predatory insect species demonstrates substantial viral diversity and suggests the potential for interspecies viral transmission. Further studies on viruses associated to agricultural insect populations are essential to elucidate possible effects on biological control strategies based on trophic interactions, determine their functional roles in agroecological systems, promote biodiversity conservation, and comprehend viral evolutionary trends.

The rapid expansion of environmental DNA (eDNA)-based biodiversity monitoring has heightened the need for accurate and well-curated taxonomic reference databases. Although mitochondrial cytochrome oxidase I (COI) is widely used, the mitochondrial 12S ribosomal RNA gene (12S rRNA) has increasingly demonstrated strong taxonomic assignment success in chondrichthyan metabarcoding applications. The South African coastline supports one of the most diverse chondrichthyan faunas globally. However, as in many regions, coverage of 12S rRNA reference databases has remained limited. Well-represented reference libraries are critical for improving the accuracy of eDNA-based species detection. Here, we aimed to expand the regional 12S rRNA reference database for South African chondrichthyans, thereby supporting both local and global eDNA applications for widely distributed species. A total of 36 chondrichthyan species, represented by 69 individuals, were sequenced to expand the 12S rRNA reference library for sharks, rays and chimaeras from South Africa's Indian and Atlantic Ocean coastlines. A newly developed primer set (V05F_898E / teleoR_Elas), designed to overlap with the commonly used Elas02 region, achieved consistent amplification across diverse lineages. The new data increased regional reference coverage from 50.3% to 69.1% and added 18 species globally. Sequence authenticity was confirmed through comparison with GenBank, and Bayesian phylogenetic analyses showed that 97.2% of sequences clustered within their expected family-level lineages, although some uncertainties remained in groups with low mitochondrial divergence or complex taxonomic histories. Percent identity analyses revealed high intraspecific similarity and clear interspecific separation across taxa. However, comparative in silico analyses of the shorter Elas02 fragment demonstrated reduced phylogenetic resolution and less consistent clustering among closely related taxa. While the Elas02 region is suitable for accurate amplicon sequence variant (ASV) matching in eDNA metabarcoding, the longer 12S rRNA fragment generated here provides improved phylogenetic resolution and may aid in the identification of unknown or ambiguous ASVs. The expanded 12S rRNA reference library and associated phylogenetic analyses expanded genetic resources for South African chondrichthyans and support global applications. The newly developed marker can be incorporated in future eDNA studies dealing with elasmobranchs, since it can have the added benefit of providing more phylogenetic resolution than the short Elas02 fragment.

Understanding and managing the impacts of climate change on ecologically and economically important plant species requires integrated modelling approaches. In this study, we developed an environmental modelling and decision-support framework for assessing the current and future habitat suitability of Nepeta persica Boiss. in Fars Province, Iran. The framework combines bivariate models (FR, WofE, IofE) and machine learning algorithms (GLM, GAM, ANN, MaxEnt, XGBoost, ENET) with fuzzy Multi-Criteria Decision Analysis (AHP, TOPSIS, VIKOR), enabling both quantitative habitat forecasting and structured decision support. Results indicated that temperature and elevation are the dominant drivers shaping species distribution. Projections under SSP245 and SSP585 scenarios suggest up to 30% contraction of suitable habitats by 2100, accompanied by an eastward and upslope shift. These outcomes provide critical insights for sustainable management, highlighting climatically buffered highlands as potential refugia for conservation and climate-resilient cultivation. By linking model-based ecological forecasting with participatory decision analysis, this research contributes to the development of adaptive management strategies aligned with the Sustainable Development Goals (SDGs 2, 13, and 15), supporting both biodiversity conservation and rural livelihood resilience under global change.

Monitoring wildlife in remote areas is a key challenge in conservation, with traditional methods proving increasingly inadequate in the face of accelerating biodiversity loss. Uncrewed Aerial Vehicles (UAVs) or drones help bridge data gaps, but methods require careful development and validation to ensure protocols are appropriate, accessible, reproducible, and generate reliable data. Herein, we develop detailed UAV-based protocols for surveying the endangered marine iguana (Amblyrhynchus cristatus), a lizard that is endemic to the coastlines of the Gal&#xe1;pagos Islands, Ecuador. We outline steps from image collection and processing, through locating and counting animals, before validating results against traditional methods. We find that UAV-based surveys outperform traditional ground-based surveys in terms of count reliability and effort in the field in different types of terrain and various population densities. Moreover, we show that consumer-level drones can be used effectively - even by newly trained pilots - and describe a standardised manual flying protocol that mimics automated flying whilst maintaining flexibility in the field. Finally, we recommend the use of orthomosaics (geometrically corrected, high-resolution aerial image maps) for surveys on flat terrains and 3D models (digital representations of the surface in three dimensions) for cliffs and compare several common image-processing platforms in terms of success to reconstruct marine iguanas. Our protocols advance the effective monitoring of Gal&#xe1;pagos marine iguanas. Whilst they were specifically developed for this species, we postulate that these could be applicable for other species across the archipelago, or in coastal and open landscapes worldwide.

Forests are vital for regulating climate and sustaining biodiversity, but climate change threatens their ability to do so, especially in the tropics. Our knowledge of how tropical forests and their constituent trees will respond to changes in climate is largely based on functional trait studies; however, few previous studies have investigated trait changes within individual tropical trees across decades, limiting our ability to predict the future of these forests. In this study, we leveraged historical and contemporary botanical specimens collected from the same individual trees in the southern Peruvian Amazon, measured a suite of leaf traits to test for individual-level trait changes over nearly 40&#x2009;years, and then related these changes to concurrent changes in local climate. We hypothesized that trees have acclimated their functional traits in response to increasing air temperatures and drought intensification and that this acclimation should help to maintain stable leaf temperatures through time. In accord with our hypothesis, we found significant decreases in measured leaf traits, including size and shape metrics and stomatal traits, within individuals through time. We used these measured traits to model leaf temperatures through time, which increased faster than would be expected based on changes in air temperature alone. This accelerated warming of leaves was due to decreased stomatal conductance, a potential acclimation of trees to dry season intensification and rising [CO2], thus limiting leaf transpirational cooling. In other words, trees have decreased abilities to cool their leaves, and consequently they may be approaching critical thermal thresholds faster than they would in the absence of water limitation. Our study provides evidence that while individual trees are acclimating to climate change, tropical forests are undergoing increasing thermal stress and that intensifying drought may be elevating this risk.

Accurate species delimitation is crucial for biodiversity research and conservation, yet it remains challenging in taxon undergoing recent radiation. Gentiana is a species-rich genus that has undergone recent radiation. In this study, we assessed the phylogenetic relationships within G. flexicaulis complex, which is endemic to the Qinghai-Tibet Plateau, and explored the underlying evolutionary causes. By combining a large set of single-copy orthologous genes, complete chloroplast genome sequences, and morphological data covering its distribution range, we clarified the taxonomic positions of G. flexicaulis, G. complexa and G. subuniflora. Both nuclear and chloroplast phylogenies revealed robust phylogenetic relationships within the complex. The results clarified the delimitation of G. flexicaulis and identified three sub-lineages within the species. The East and West sub-lineages are geographically isolated by the Qionglai Mountains and differ morphologically in calyx and stem leave length. The third sub-lineage represents a new subspecies proposed in this study, named G. flexicaulis subsp. brevicorolla, which is diagnostically distinct from the autonym in having a shorter corolla and calyx, as well as smaller leaves. G. flexicaulis subsp. brevicorolla is closed related to G. complexa in morphology, sharing short corolla and calyx traits, but it shows clear phylogenetic independence in both nuclear and chloroplast phylogenies. Evidence from orthologous genes and genomic SNPs indicated that incomplete lineage sorting and hybridization in the G. flexicaulis complex occur mainly within species rather than among species. In summary, our study refines the delimitation of G. flexicaulis and demonstrates the utility of morphological statistics at the population level across geographical variation in recently radiated taxon.

Agricultural intensification is a major driver of land use change, thereby reducing biodiversity and leading to population declines across various animal groups. In response, animals can mediate some negative fitness impacts and navigate through agricultural landscapes with reduced resource availability by changing their habitat selection via movement decisions - particularly when constrained by central-place foraging, which requires balancing travel costs against energetic returns. Here, using miniature ATLAS tags (Advanced Tracking and Localisation of Animals in real-life Systems), we tracked 101 house martins and 87 barn swallows at high-resolution to investigate their state-specific habitat selection and mapped the insect abundance and diversity across an intensively used agricultural landscape. Both species mainly avoided arable fields and increasingly selected for forests and water bodies with distance from the colonies. House martins ranged farther from colonies than barn swallows and also showed strong distance-dependent selection for structurally complex habitats, such as extensive grasslands and green areas within villages. Furthermore, house martins selected for proximity to water bodies, while barn swallows' selection focused on proximity to woody vegetation structures. During our 2023 insect sampling window, habitat selection tracked mapped insect richness more closely than mapped insect abundance. Distance-dependent divergence in space use suggests horizontal niche differentiation between sympatric central-place foragers, with potential implications for coexistence. Combined, our findings point to the importance of maintaining extensively used grasslands and small-scale habitat structures within intensively managed farmland to improve the abundance and diversity of prey for farmland passerines.

Amidst global climate change, the escalating atmospheric CO2 levels have intensified ocean acidification (OA), significantly impacting the structure and function of marine ecosystems. Seagrass beds, representative nearshore ecosystems, play a pivotal role in carbon sequestration, biodiversity preservation, and nearshore environmental equilibrium. Rhizosphere microorganisms within seagrass beds, essential components of the ecosystem, drive material cycling and energy flow. Their community structure and functions demonstrate heightened sensitivity to environmental variations. While previous studies have primarily focused on the effects of ocean acidification on seagrass hosts, limited attention has been given to the rhizosphere. Therefore, this study selected Zostera japonica as the focal species and systematically evaluated changes in the structure and function of the rhizosphere bacterial community across varying acidification levels (400 ppm, 1,000 ppm, 2,000 ppm CO2) within an ocean acidification context. The results revealed a significant decline in the richness and diversity of the rhizosphere bacterial community under acidification, accompanied by shifts in community composition characterized by an increase in the relative abundance of Bacteroidota and Tenacibaculum with escalating acidification levels. In high acidification conditions, bacterial network interactions exhibited a trend toward simplification; yet the number of key taxonomic units increases, and there was a shift in community assembly from stochastic to deterministic processes. Functional predictions indicated the enhancement of microbial carbon sequestration and nitrogen fixation under acidification, while denitrification and specific sulfur metabolism pathways were inhibited. This implies that in acidified environments, the rhizosphere bacterial community may enhance carbon and nitrogen fixation to uphold nutrient supply. Against the background of escalating global climate change and ocean acidification, seagrass beds, as crucial blue carbon sink ecosystems, face formidable challenges to their ecological functions and stability. Rhizosphere microorganisms of seagrasses, serving as the "second genome" of the seagrass host, play a central role in material cycling, nutrient supply, and system stability within seagrass beds. They are a key biological component that supports seagrass adaptation to environmental changes. Therefore, investigating the response and adaptation mechanisms of seagrass rhizosphere bacterial communities under ocean acidification is essential for deepening our understanding of the stability and resilience of seagrass bed ecosystems.