Search Results (603)

Rapid urbanization intensifies habitat fragmentation, creating a need for spatially differentiated ecological corridor planning. Conventional delineation often relies on empirical symmetric buffers that do not represent urban matrix heterogeneity. Focusing on central Shanghai and using avian biodiversity as the conservation context, we integrated morphological spatial pattern analysis (MSPA) to identify ecological sources, raster-based principal component analysis (PCA) to construct a composite resistance surface, minimum cumulative resistance (MCR) to extract potential corridors, and circuit theory to estimate modeled connectivity. Corridors were divided using a nominal 300 m segmentation interval, and side-specific candidate widths were identified from inflection features in cumulative connectivity–benefit curves. XGBoost–SHAP was subsequently used to describe within-model associations for ten predictors: natural ecological factors (canopy height, NDVI, and tree cover), anthropogenic socio-environmental factors (architecture area proportion, distances to water and roads, and nighttime light), and avian diversity indices (richness, Simpson, and Shannon–Wiener). Key results were as follows: (1) 30 sources and 66 potential corridors were identified, with modeled connectivity showing a peripheral-high and central-low pattern; the Outer Ring Green Belt formed the principal network backbone. (2) Most candidate total widths (64.83%) were in the 100–200 m range, while 20.19% exceeded 200 m and 14.98% were below 100 m. (3) Within the fitted model, natural ecological predictors had higher mean absolute SHAP contributions than anthropogenic predictors and avian diversity indices, and canopy height had the largest contribution. Because seven environmental predictors also entered resistance-surface construction, these SHAP contributions are interpreted as model-dependent attributions rather than independent environmental drivers. The width estimates are conditional on the adopted resistance and parameter settings and have not been validated with independent bird movement or habitat-use data. They therefore provide planning hypotheses and candidate spatial estimates rather than validated ecological thresholds. Full article

Microorganisms are sensitive indicators of aquatic environmental quality and ecosystem stability. Caohai Wetland, a typical subtropical plateau karst wetland suffering ecological degradation under combined natural-anthropogenic disturbances, is one of the three major plateau freshwater lakes in China and a critical wintering habitat for the Black-necked Crane (Grus nigricollis) along the East Asian–Australasian Flyway. Previous research has focused mainly on phytoplankton, aquatic plants, birds, and the water environment, while knowledge of its microbial community, especially the joint controls of multi-factor hydro-environmental conditions and aquatic plants across the whole lake, remains limited. To determine the diversity and seasonal dynamics of the microbial community and the key environmental factors driving it, water samples were collected from 17 sites in Caohai Lake across four seasons during 2022–2023 and analyzed by 16S rRNA gene sequencing, combined with measurements of hydro-physicochemical parameters and aquatic plant biomass and coverage. Among the 1370 ASVs obtained, the top five phyla in descending order of abundance were Pseudomonadota (45.04%), Bacillota (21.75%), Bacteroidota (11.82%), Actinomycetota (11.09%), and Verrucomicrobiota (3.65%). The microbial community exhibited significant seasonal variations, with richness, the Shannon-Wiener index, and Pielou’s evenness all significantly higher in autumn than in the other three seasons and lowest in spring. Correlation analysis indicated that water temperature was the primary driver of microbial community structure, while SD, EC, and COD also exerted significant influences; in addition, aquatic plant biomass and coverage were identified as key environmental factors shaping the microbial community composition in Caohai. This study provides fundamental monitoring data to support the assessment of the evolutionary trends of the Caohai wetland ecosystem and its conservation and management. Full article

Urban campuses represent complex landscapes comprising buildings, roads, water bodies, and vegetation patches. Differences in spatial structures among landscape microhabitats and levels of human disturbance may influence avian acoustic activity and birdsong soundscape characteristics. However, continuous spatiotemporal dynamics of birdsong soundscapes and differences in acoustic community composition at the campus scale remain insufficiently explored. To address this gap, this study integrates 24 h continuous passive acoustic monitoring across replicated landscape microhabitats with field-validated deep learning-based birdsong identification, enabling diel, spatial, and acoustic-community patterns to be evaluated within a unified fine-scale campus framework. Using the Qingdao Agricultural University campus as a case study, we established 25 monitoring sites from March to May 2026 across five landscape microhabitat types: streamside, lakeshore, green space, building, and edge. Twelve days of 24 h continuous passive acoustic monitoring were conducted, and target bird species were identified using MFCC–based acoustic features combined with the EfficientNet–B0 multi-label classification model, whose field applicability was further evaluated using an independently selected and manually annotated subset of the campus recordings. The results revealed that birdsong soundscapes across different landscape microhabitats exhibited consistent diel rhythms, with the highest avian acoustic activity occurring during the early-morning period. Spatially, avian acoustic activity and the number of detected target bird species were generally higher in streamside-type, lakeshore-type, and green space-type microhabitats than in building-type and edge-type microhabitats. Significant differences in birdsong acoustic community composition were observed among different landscape microhabitats and fixed clock-time periods, showing species-specific spatiotemporal responses. These findings demonstrate the value of species-resolved birdsong soundscape monitoring as a complementary approach for fine-scale ecological assessment and provide site-specific evidence for landscape microhabitat management and bird-friendly planning on urban campuses. Full article

Hangzhou Bay is an estuarine ecosystem on the Yangtze River Delta and a key wintering habitat for waterbirds. However, suitable waterbird habitats have been degrading and fracturing. Therefore, we aimed to assess waterbird habitat suitability and identify the principal factors affecting quality in Hangzhou Bay National Wetland Park. Habitat suitability index (HSI) models were constructed for wading and swimming birds using water source conditions, disturbance levels, concealment, and food abundance. The models adopted consistent factor weights but differentiated the grading criteria for the waterbird groups. Applicability was validated using bird survey data collected in 2025, and habitat suitability was quantitatively assessed using field and literature data. Food abundance and water source conditions were dominant factors influencing habitat suitability; concealment and disturbance levels had minor effects. The abundances of wading and swimming birds increased with HSI values, although limited validation sites constrained these relationships. Positive trends indicate that the HSI models may capture the spatial variation in habitat use. Grade III or higher areas comprised 96.67% and 74.21% of the total area for wading and swimming birds, respectively; no Grade I habitats were identified. Overall, the study area provided favorable habitats for waterbirds, although habitat suitability differed between the groups. These findings may provide a quantitative reference for the targeted conservation and restoration of waterbird habitats in the Hangzhou Bay wetland. Full article

Mountain ecosystems serve as natural laboratories for studying biodiversity distribution along elevational gradients. This study was conducted at Hualongshan National Nature Reserve in the Daba Mountains, Shaanxi Province, using line transect surveys, mist-netting, and passive acoustic monitoring (PAM). We systematically examined the spatial variation and drivers of bird community diversity along the elevational gradient, integrating α and β diversity across taxonomic, functional, and phylogenetic dimensions. A total of 91 bird species from 8 orders and 33 families were recorded, among which breeding birds (84 species) were dominated by Oriental (55.95%) and Palaearctic (26.19%) species, reflecting significant transitional characteristics between the two realms. Alpha diversity exhibited a mid-elevation unimodal pattern, peaking at 1951~2250 m in the coniferous and broad-leaved mixed forest zone. β diversity decomposition revealed that taxonomic diversity was dominated by turnover, functional diversity by nestedness, and phylogenetic diversity by balanced contributions of both, indicating asynchrony among dimensions. Random forest models identified precipitation difference as the primary driver of taxonomic β diversity, while Enhanced Vegetation Index (EVI) difference dominated functional β diversity, revealing differentiated mechanisms by which water availability and vegetation productivity shape species composition and functional structure, respectively. Our findings highlight the asynchrony of multidimensional bird diversity, emphasizing that a single dimension cannot fully capture community assembly mechanisms, and provide theoretical and practical reference for mountain biodiversity conservation. Full article

Skeletal muscle growth and development represent a pivotal biological process that determines both the yield and quality of poultry meat. As chickens age, there is an observable shift in their muscle structure, function and metabolic properties. However, the molecular mechanisms by which age regulates chicken muscle development and meat quality formation are not yet fully understood. The objective of this study was to elucidate the fundamental molecular mechanisms through which the aging process influences the development of chicken muscle and the quality of meat. A total of 20 female Dahen chickens, comprising 10 birds at 3 months of age and 10 at 72 months of age, were subjected to systematic measurements of meat quality indexes and muscle fiber characteristics. From each age group, 3 out of the 10 birds were randomly selected for breast muscle transcriptome analysis. The results demonstrated that aged chicken breast muscle exhibited reduced tenderness, augmented intramuscular fat content and water-holding capacity, while muscle fibers demonstrated significant hypertrophy and reduced density. A total of 819 differentially expressed genes (DEGs) were identified by RNA-seq, which were predominantly enriched in the biological processes of muscle system process, muscle organ development, and skeletal muscle cell differentiation, and were involved in the pathways of cytoskeleton in muscle cells, and extracellular matrix (ECM)–receptor interaction signaling, among others. The expression of key genes, such as COL1A2, THBS2, FN1, and MYBPC1, was found to be significantly altered, a finding that was verified by qPCR in agreement with the sequencing results. The study demonstrated that age impacts meat quality traits by inducing muscle fiber hypertrophy, ECM remodeling and metabolic reprogramming. The related genes provide a valuable reference point for understanding the genetic regulation of avian muscle development and meat quality. Full article

Background: Improving meat quality while maintaining growth efficiency remains a major challenge in poultry production. However, the molecular mechanisms underlying breed-specific meat quality variation remain unclear. This study aimed to investigate how breed-specific growth patterns influence meat quality and elucidate metabolic and transcriptional mechanisms involved. Methods: Pectoralis major meat quality traits and multi-omics profiles were characterized in three genetically distinct chicken breeds—the fast-growing Small White-Feathered chicken (XBJ), the slow-growing Huiyang Bearded chicken (HXJ), and the layer-type Hy-Line Brown chicken (HLH)—at 50, 180, and 300 days of age. Twelve birds per breed per age were used for phenotypic measurement (n = 108 in total), and eight birds per breed per age were subjected to metabolomic and transcriptomic profiling. Phenotypes were analyzed using linear mixed-effects models with breed, age, and their interaction as fixed effects and pen nested within breed as a random effect, followed by Tukey-adjusted pairwise comparisons (p < 0.05). Differential metabolites were screened by OPLS-DA (VIP > 1, p < 0.05), and differentially expressed genes were identified using DESeq2 (|log2FC| ≥ 1, FDR < 0.05). Integrative analyses were performed to identify key genes, metabolites, and pathways associated with meat quality. Results: Phenotypic evaluation revealed a breed-dependent growth–meat quality trade-off, with XBJ exhibiting superior growth but poorer water-holding capacity and meat color, whereas HXJ and HLH showed better tenderness and color at the expense of growth. Metabolomic analysis revealed lipid metabolism as a major contributor to breed-specific divergence, with triglyceride-driven divergence predominating at early and middle stages, whereas later-stage differences involved glycerophospholipid and amino acid metabolism. Transcriptomic analysis revealed significant breed-specific differences in expressed genes at 50 and 180 days, enriched in pathways related to muscle structure, ECM remodeling, and energy metabolism, consistent with metabolic and phenotypic divergence. Integrated analyses identified 28 candidate genes and 71 core metabolites associated with meat quality traits, with PLIN1 and SLC1A6 emerging as key regulators associated with TG species, drip loss, shear force, and BMW. Conclusions: These findings reveal molecular mechanisms underlying the growth–meat quality trade-off and highlight lipid metabolic regulation as a key contributor to meat quality variation. The identified gene–metabolite networks provide insights for molecular breeding to improve chicken meat quality. Full article

Cultural ecosystem services (CES) are widely measured but rarely attributed to the specific landscape elements that generate them. We coupled element-level image recognition with service-level text analysis across 20,447 reviews and 18,997 photographs from three social media platforms covering 15 national-, provincial-, and municipal-level forest parks in Guangzhou, China (2020–2024). A 2660-term dictionary quantified nine CES; a fine-tuned deep learning classifier identified 28 landscape elements; multiple correspondence analysis described the element-service structure and ridge regression tested associations within four case parks. Natural elements aligned with ecological, aesthetic, and inspirational services and built elements with cultural, social, and wellness services, but two results qualify that division. First, individual elements were associated with different services in opposite directions: seasonal forest with higher aesthetic appreciation but lower recreation, water features with higher aesthetic value but lower inspiration. Second, the mapping differed across the four case parks rather than holding constant; in the municipal case park, only built facilities positively predicted social interaction. These four parks are illustrative exemplars rather than representative samples of their tiers. Dynamic biological elements (birds 0.43%, insects 0.12%, fish 0.08%) ranked lowest of all 28 elements. These are descriptive associations awaiting mechanistic explanation; on that reading, planning for CES would be better organized around intended services than element inventories, calibrated to the individual park. Full article

The Guangdong Haifeng Coastal Wetlands (Ramsar Site No. 1727) in Shanwei City are a critical habitat for migratory birds, but the long-term evolution and driving mechanisms of ecological vulnerability under rapid urbanization remain insufficiently understood. In particular, few studies have quantitatively characterized the temporal shifts in the relative roles of anthropogenic pressures and conservation policies over decadal scales. This study developed a landscape pattern-based ecological vulnerability assessment model integrating spatial autocorrelation, Geodetector, the PLUS model, and spatial overlay analysis to diagnose the dynamics and driving mechanisms of the wetlands from 1980 to 2018. The results showed that farmland and woodland dominated Shanwei City, while water bodies consistently dominated the Haifeng Wetlands. Ecological vulnerability exhibited significant spatial heterogeneity, with levels higher in the northwest and lower in the southeast. Forest and water expansion overlapped with vulnerability reduction, whereas built-up and farmland expansion matched increases in vulnerability. Land-use intensity, elevation, and mean annual temperature were identified as the primary drivers. The drivers of built-up land expansion shifted from population-related pressures during 1980–2000 to stronger policy regulation effects after 2000, indicating a transition in human–land interactions. Conservation policies, including nature reserve establishment and Ramsar designation, provided important institutional support for ecological management. These findings highlight the importance of integrating long-term land-use dynamics with natural, socioeconomic and policy contexts to improve the understanding and management of coastal wetlands vulnerability under rapid urbanization. Full article

Broiler litter quality is an important determinant of animal welfare, environmental conditions, and production efficiency. This study evaluated the effects of incorporating a biodegradable superabsorbent polymer (SAP) into chopped straw (CS) litter on broiler welfare, production performance, litter characteristics, environmental conditions, and meat quality. A total of 1000 Ross 308 broiler chickens were randomly allocated to four treatments: a control group (CON) and three groups receiving SAP at 30, 60, or 100 g/m² in the pen (H30, H60, or H100). Birds were reared for 42 days under commercial conditions. Growth performance, welfare indicators, gaseous emissions, litter characteristics, slaughter traits, and breast muscle quality were assessed. SAP supplementation had no adverse effects on body weight, feed conversion ratio, mortality, slaughter performance, or meat quality. Although litter dry matter content was lower in the H60 and H100 due to the water-retention capacity, NH₃ concentration at the bird level was significantly reduced. SAP supplementation also improved selected animal welfare indicators, particularly by increasing the proportion of birds with score 0 of footpad dermatitis (FPD) from 46–59% to 69–79%. These findings indicate that biodegradable SAPs represent a promising litter amendment for improving broiler welfare and housing conditions without compromising production performance or meat quality. Full article

Increasing antimicrobial resistance and restrictions on antibiotic use in poultry have drawn attention to phytogenic products as a complementary approach for controlling enteric bacterial infections. The aim of this study was to evaluate the effects of a phytogenic product (Herba Top Salmonella, HTS) on selected cultivable intestinal bacterial populations, intestinal histomorphology and tissue distribution of Salmonella Typhimurium in experimentally infected broiler chickens. A total of sixty one-day-old Ross 308 broilers were randomly assigned to six experimental groups (10 birds/group; two pens/group, five birds/pen, with the pen considered the experimental unit. Birds in three groups were experimentally challenged with Salmonella enterica subsp. enterica serovar Typhimurium, and HTS was administered in drinking water for 14 consecutive days at two nominal concentrations (3 mL/L and 6 mL/L). Intestinal microbiological parameters, histomorphometric characteristics, and the presence of Salmonella Typhimurium in tissues by immunohistochemistry were evaluated. The effects of infection status, HTS concentration, and their interaction were analyzed using two-way ANOVA. HTS administration was associated with reduced counts of total aerobic bacteria, Escherichia coli and Enterobacteriaceae counts. In experimentally infected broilers, HTS treatment was also associated with reduced Salmonella Typhimurium in intestinal tissue and significant changes in intestinal histomorphometric parameters, including increased crypt depth and mitotic activity. The observed responses were influenced by both infection status and the HTS nominal concentration. Because of the limited number of independent experimental units and the absence of individual HTS intake measurements, these findings should be considered exploratory preliminary findings, and further studies with larger animal groups under commercial production conditions are required. Full article

This study evaluated the effects of Fibrafid, a plant-based functional feed additive, on growth performance, carcass traits, meat quality, and intestinal histomorphometry of broilers fed standard or moderately nutrient-reduced diets. A total of 432 one-day-old Ross 308 chicks (initial body weight, 44.9 ± 0.30 g) were randomly allocated to a 2 × 3 factorial arrangement comprising two dietary nutrient densities (standard or diets with 1.5% lower metabolizable energy and 5% lower digestible amino acid density) and three Fibrafid inclusion levels (0, 1.5, or 2.5 kg/ton). Each treatment comprised six replicates of 12 birds (six males and six females) and was evaluated from day 1 to 24. Dietary nutrient reduction affected growth performance and breast meat quality pH and ultimate lightness values, whereas Fibrafid supplementation, particularly at 2.5 kg/ton, improved overall gain by 5.3%, grower-phase feed conversion ratio by 4.0%, EPEF by 8.08%, relative thymus weight by 64.8%, while reducing abdominal fat deposition by 27.1% relative to the unsupplemented control (p < 0.05). Several breast meat quality traits were also improved, including greater water-holding capacity and myofibril fragmentation index and lower drip and cooking losses (p < 0.05). Jejunal morphology was enhanced, as indicated by increased villus dimensions and goblet cell density (p < 0.05). Significant Diet × Fibrafid interactions were observed for grower performance, EPEF, overall feed intake, and several intestinal morphological variables (p < 0.05). In conclusion, Fibrafid supplementation, particularly at 2.5 kg/ton, was associated with improved growth performance, EPEF, selected carcass and breast meat quality traits, and jejunal morphology during the first 24 days of age. These findings suggest that Fibrafid may be a promising natural feed additive for broiler diets formulated at standard or moderately reduced nutrient densities. However, further studies extending to market age and evaluating nutrient digestibility, intestinal microbiota, blood biochemical indices, and economic returns are warranted to clarify its mechanisms and practical value under commercial production conditions. Full article

Antimicrobial resistance (AMR) is a major One Health challenge driven by antimicrobial misuse in human medicine, veterinary practice, animal production, and polluted environments. Migratory birds move among wetlands, farms, wastewater-affected habitats, landfills, and coastal ecosystems and may acquire and redistribute antimicrobial-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs) across ecological and political boundaries. This perspective synthesizes evidence on exposure sources, bacterial reservoirs, resistance determinants, cross-species interfaces, and surveillance priorities while explicitly distinguishing four claims: detection or carriage, persistence in individual birds, redistribution along migratory routes, and onward transmission to recipient hosts or environments. Published studies report multidrug-resistant Escherichia coli, Klebsiella pneumoniae, Salmonella spp., Enterococcus spp., and Campylobacter spp., with determinants including blaCTX-M, blaTEM, blaNDM, mcr, tet, sul, and qnr genes. The eight evidence groups summarized here constitute an illustrative, non-comprehensive selection; they are predominantly observational surveys or screenings, and none reconstructs a complete source–bird–destination–recipient transmission chain. Taxon-specific ecology modifies exposure: gulls and storks frequently exploit refuse and wastewater, waterfowl and shorebirds connect aquatic habitats, whereas passerines often reflect more local point-source contamination. Current evidence therefore supports migratory birds primarily as mobile sentinels and opportunistic carriers of anthropogenic AMR, while acknowledging possible natural or ancestral resistance in avian-associated microbiota. Future surveillance should combine longitudinal sampling, baseline cohorts such as pre-migratory nestlings, paired bird–water–soil–sediment sampling, whole-genome sequencing, plasmid profiling, telemetry, environmental DNA, wastewater-based epidemiology, and interoperable veterinary reporting. Practical mitigation requires antimicrobial stewardship, wastewater and landfill control, farm biosecurity, and coordinated veterinary, environmental, and public-health action. Full article

In this study, we evaluated the effects of a commercial blend of organic acids (formic acid and propionic acid) added to drinking water on the microbiota of broilers experimentally challenged with Salmonella enterica serovar Minnesota. A total of 108 broilers were randomly assigned to three groups, each with 36 birds: the Treatment group (treated with organic acids + challenge), a Positive Control group (challenge only), and a Negative Control group (no challenge). At seven days of age, broilers in the Treatment group received the organic acid blend through their drinking water (0.2 mL/L/drinking water). At nine days of age, broilers from the challenged groups were inoculated via feed with S. Minnesota (Treatment group—mean: 1.45 × 10⁴ CFU/g; Positive Control group—mean: 3.47 × 10⁴ CFU/g). Swab samples were collected for Salmonella enumeration and cecal content for bacterial community profiling using 16S-rDNA gene sequencing. Our results demonstrated that supplementation with organic acids positively modulated the cecal microbiota of broilers under S. Minnesota challenge. Broilers receiving the organic acid blend showed improvements in microbial community composition, including an increased abundance of bacterial genera associated with butyrate production, which are recognized for their beneficial effects on intestinal health. Overall, our findings suggest that the blend of organic acids may serve as a nutritional strategy for supporting intestinal health and microbiota stability in broilers challenged with S. Minnesota. Full article

Urban grey infrastructure, including transport corridors, flood-control systems, drainage facilities, railway margins, and industrial brownfields, is often treated in conventional planning as functionally vacant or ecologically marginal space. In this study, grey infrastructure is defined as engineered or infrastructure-dominated urban spaces and their residual or edge landscapes, rather than as green infrastructure. Yet such spaces may still contain spontaneous vegetation, water edges, soil patches, and sheltered microhabitats that can support birds, insects, small mammals, and other urban species in highly urbanized environments. From a multispecies justice perspective, this study examines spatial mismatches between PPGIS-derived public recognition and habitat quality modeled using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model in urban grey infrastructure. Using Zhanggong District, Ganzhou, China, as a case study, we developed an integrated framework that combines public participation geographic information systems (PPGIS), grid-based public recognition mapping, and the InVEST Habitat Quality model. Based on 260 valid questionnaires, participants identified locations associated with aesthetic preference and perceived habitat potential. These mapped perception points were converted into a grid-based public recognition indicator and compared with modeled habitat quality. The results indicate a marked perception-habitat mismatch. High public recognition was frequently associated with visually ordered, accessible, and highly managed urban spaces, whereas high modeled habitat quality was more strongly related to vegetated, riverine, peripheral, and semi-natural spaces. The spatial classification shows that aesthetic mismatch areas, where public recognition was high but modeled habitat quality was low, covered 43.20 km², accounting for 7.16% of the study area, whereas hidden ecological value areas, where modeled habitat quality was high but public recognition was low, covered 118.21 km², accounting for 19.59%. This study provides a replicable framework for identifying perception–habitat mismatches and supports more ecologically informed and inclusive strategies for regenerating urban grey infrastructure. More specifically, the study extends an established perception-ecology debate to grey infrastructure and residual urban spaces and demonstrates how PPGIS-derived public recognition and InVEST-modeled habitat quality can be compared within the same grid framework to locate spatially explicit alignment and mismatch. Full article