Search Results (437)

Driven by the concept of sustainable aquaculture, natural feed additives with growth-promoting, antioxidant, and immune-enhancing properties have become a key research focus. This study assessed the effects of dietary red pepper powder (Capsicum annuum) supplementation at 0%, 0.5%, 1.0%, and 2.0% over 50 days on the growth, digestive function, immune and antioxidant capacities, intestinal microbiota, and gene expression in Strongylocentrotus intermedius (S. intermedius). The results indicated that red pepper powder significantly promoted growth and decreased the feed conversion ratio (FCR) (p < 0.05), with the 1.0% group showing the highest growth rate. Additionally, supplementation improved gonadal coloration and increased crude protein and lipid contents in the gonads, particularly in the 1.0% and 2.0% groups (p < 0.05). Supplementation with 1.0% and 2.0% red pepper powder enhanced digestive, immune, and antioxidant enzyme activities, while reducing malondialdehyde (MDA) levels, indicating lower lipid peroxidation. α-diversity analysis revealed the highest ACE, Chao, and Shannon indices and the lowest Simpson index in the 1.0% group, indicating greater microbial diversity. Community analysis revealed that in the red pepper powder treatment groups, beneficial bacteria, such as Firmicutes and Unclassified_f__Rhodobacteraceae, increased in relative abundance, while potential pathogens like Arcobacter, and Epsilonbacteraeota were less abundant. Red pepper powder supplementation upregulated key immune- and antioxidant-related genes while downregulating pro-inflammatory and stress-associated genes. Overall, optimal dietary supplementation of red pepper powder, particularly at 1.0%, enhanced antioxidant and immune functions, optimized intestinal microbiota, mitigated oxidative stress, and consequently promoted growth, improved gonadal quality, and strengthened overall health in S. intermedius. Full article

The microbiota within crop milk not only participates in the physiological regulation of parent pigeons but also promotes the healthy growth of squabs. Consequently, microbial sequencing of both crop milk and the saliva through which it passes is essential to elucidate microbial changes in both compartments during the raising brooding period. This study sampled crop milk and saliva of Mimas at three distinct time points corresponding to Days 1, 4, and 7 of raising brooding, and collected samples from three pairs of healthy breeding pigeons with similar body weights at each time point. The results demonstrated that α diversity increased in both the crop milk and salivary microbiota over time, surpassing the levels observed at the initial secretion stage. Compared to R1, the Simpson index of the salivary microbiome was significantly higher at R7 (p < 0.05). Ligilactobacillus constituted the most abundant genus in crop milk, whereas saliva harbored a greater diversity of potentially pathogenic bacteria. Phylogenetic analysis revealed a close evolutionary relationship between Ligilactobacillus and Enterococcus in crop milk, suggesting potential functional synergy. Furthermore, functional prediction indicated that ABC transporter-related genes presented the lowest expression in the crop milk microbiota during its peak secretion period. Notably, Pearson correlation analysis revealed a significant negative correlation between Ligilactobacillus abundance in crop milk and Psittacicella abundance in saliva. In summary, the crop milk and salivary microbiota exhibit distinct temporal dynamics, and their specific microbial compositions and functions can provide new research directions for the healthy breeding of squabs. Full article

Elucidating the relationship between changes in insect assemblage structure and diversity and the number of years of ecological restoration will help us evaluate the effectiveness of ecological restoration. Our objective is to investigate the response of the structure and diversity of insect communities in the ecological restoration area of Yimin Surface Mine in Inner Mongolia to different restoration years (1 year, 4 years, 7 years) by monitoring in 2018, 2021, and 2024. A total of 1282 insect specimens were collected using sweep-netting methods, representing 70 species from 46 families across 8 orders. The results demonstrated that as restoration progressed, insect taxa significantly increased from 25 to 55 species (p < 0.01), with key functional groups (Coleoptera and Lepidoptera) showing marked richness enhancement. α-diversity indices (Shannon–Wiener and Margalef) significantly increased, while the Simpson dominance index decreased, indicating a more homogeneous species distribution. β-diversity analysis revealed reduced compositional dissimilarity among plots during later restoration stages, reflecting enhanced assemblage stability. The trophic structure shifted from phytophagous dominance to stabilized proportions across all feeding guilds, signaling food web maturation and ecosystem development. Overall, local ecological restoration projects had a significantly positive effect on insect survival and biodiversity development. Our research addresses a gap in faunal assemblage studies of coal mine rehabilitation zones. Full article

The synergistic interaction between landscape fragmentation and climate change poses a critical threat to tropical forests. However, the long-term dynamics of these coupled pressures have been little explored. This study analyzes half a century (1979–2023) of changes in landscape structure and climate across five coastal watersheds in Oaxaca, Mexico a region of high biological and socio-economic diversity. Using multitemporal satellite imagery (Corona, Orthophotos, RapidEye and Planet), we quantified the trajectories of tree cover, fragmentation (Largest Patch Index, LPI; Simpson’s Diversity Index, SIDI), and connectivity (Probability of Connectivity Index, PC); and contrasted these with temperature and precipitation trends. Our results reveal that during the period 1979–2010, there was a slight increase in tree cover accompanied by positive landscape metrics, whereas in the period 2010–2023 a loss of tree cover was observed. Nonetheless, overall, between 1979 and 2023, the analysis indicates a net gain of 59,725 ha of tree cover, a reduction in fragmentation (LPI increased by 26.33% and SIDI decreased by 0.23), and an improvement in connectivity (PC increased by 0.35). During the same period, the average annual temperature increased by 2.3 °C, and precipitation decreased by 219 mm annually. The study concludes that the system is undergoing a transition from a spatial configuration limitation to a climate-induced habitat quality limitation. Full article

This study evaluates the impact of using biogas slurry (BS) instead of nitrogen fertilizer (NF) on wheat soil, and aims to provide an optimized fertilization strategy for green wheat production. Five fertilization modes were tested: basal fertilizer only (CK), NF at the full-bearing stage (CF), BS at the jointing stage + NF at the grouting period (S1), NF at the jointing stage + BS at the grouting period (S2), and BS at the full-bearing stage (S3). Wheat yield in S3 treatment was not significantly different from CF (9632.57 kg·ha⁻¹), but significantly increased starch content by 23.39% (p < 0.05). Analysis of soil nutrient content showed that S3 treatment elevated ammonium nitrogen (AN) content by 98.30% during the harvest period and maintained the highest urease activity (686.45 μg·g⁻¹·d⁻¹). Microbial community analysis showed that the bacterial Shannon index under S3 treatment reached 7.09, and the abundance of Actinomycetes reached 39.40%. The fungal Simpson index was 0.02, lower than that of other treatments (p < 0.01). A comprehensive evaluation led to the conclusion that a complete replacement of BS with NF synergistically improves soil quick-acting nutrient levels, enhances soil enzyme activities, and sustains high microbial diversity, whilst maintaining wheat yield. Full article

Increasing demand for high-quality food is driving the development of biologized farming methods, which involve the use of microorganisms, including endophytes, to stimulate plant growth. However, research on the composition of endosphere microbiomes is limited. The study presents an analysis of the bacterial endophytic microbiome in lettuce seeds (Lactuca sativa L., cv. Ozornik) using high-throughput sequencing of 16S rRNA amplicons. It evaluates the taxonomic composition and putative functional properties of seed endophytic bacteria. The microbial community exhibited low diversity (Shannon index ranged from 1.1 to 1.84, Simpson index from 0.57 to 0.83). The bacterial endophytic community of lettuce seeds was dominated by Pseudomonadota (83%), Actinomycetota (14%), and Bacillota (3%). The genera identified within the microbiome included Pantoea (32%), Rhodococcus (13%), Candidatus Profftella (13%), Janthinobacterium (7%), Pseudomonas (9%), Enterococcus (3%), and Alcaligenes (2%), which exhibit a broad spectrum of beneficial properties: plant growth promotion (PGPB), suppression of phytopathogens, enhanced stress tolerance, participation in contaminant biodegradation, and heavy metal detoxification. The structure and functional potential of the microbiome vary between samples, potentially due to differences in source material and cultivation conditions. The obtained results expand our understanding of the composition and functions of endophytic bacteria in lettuce seeds, which is important for the development of novel biocontrol agents for plants consumed by humans in an unprocessed form. Full article

Landscape patterns serve as important drivers of macroinvertebrate biodiversity. However, the mechanisms through which landscape dynamics influence biodiversity across different elevation gradients in undammed rivers remain poorly understood. Here, this study investigated macroinvertebrate communities in the Chishui River, which represents the only undammed tributary maintaining a natural flow regime in the upper Yangtze River. We documented 97 macroinvertebrate taxa (3 phyla, 16 orders, and 57 families) with a mean density of 314.93 ind./m². NMDS and PERMANOVA analyses revealed significant spatial heterogeneity in macroinvertebrate community composition, but no overall seasonal variation. However, functional diversity indices (e.g., FRic) exhibited seasonal fluctuations across the river system. Furthermore, we assessed nine landscape metrics to capture heterogeneity, complexity, and fragmentation effects. Random forest modeling with nine predictors revealed that landscape heterogeneity primarily drove functional diversity in the upstream areas, whereas landscape fragmentation was the dominant factor in the downstream areas. Functional diversity, which reflects trait-based ecological roles, provides more direct insights into ecosystem processes than taxonomic diversity alone. Notably, the taxonomic diversity indices (Margalef richness, Shannon–Wiener diversity, Simpson diversity, and Pielou evenness index) showed no significant correlations with landscape metrics. These findings highlight the critical role of functional diversity in evaluating landscape-mediated ecological effects. For effective conservation, management strategies should prioritize reducing anthropogenic disturbances in downstream areas while preserving natural landscape heterogeneity. Full article

Given that suckling lambs with immature rumen development rely on intestinal microbiota for nutrient utilization, investigating the composition and functional characteristics of their intestinal microbiota is therefore of paramount importance. In this study, 16S rRNA gene amplicon sequencing technology was adopted to characterize and analyze the diversity and composition of the jejunum, ileum and cecum bacterial communities of lambs at 0, 7 and 28 days of age, and to predict the functions of the bacterial communities. The α-diversity analysis results revealed that in the jejunum of lambs, the Chao1, PD, Simpson and Shannon indexes differed significantly among the three age groups (p < 0.05). In the ileum, Shannon and Simpson indexes of the 0-days-of-age group were slightly lower than those of the 7 (8.84% and 12.66% reductions, respectively) and 28-days-of-age groups (19.34% and 15.85% reductions, respectively) (0.05 < p < 0.10). In the cecum, Simpson and Shannon indexes differed significantly (p < 0.05) among the three age groups. At the phylum level, Firmicutes (64.68%) and Proteobacteria (21.76%) dominated the bacterial communities across all intestinal segments, with a total of 42 phyla detected. At the genus level, 19 dominant genera were identified in the jejunum. Except for Bifidobacterium, which showed no significant age-related variation (p > 0.05), the relative abundance of the remaining 18 genera changed significantly with age (p < 0.05). In the ileum, compared with the 0-days-of-age group, the Lactobacillus abundance was significantly higher in the 7- and 28-days-of-age groups (p < 0.05), while the Escherichia-Shigella, Mannheimia and Enterobacter abundances were significantly reduced (p < 0.05). In the cecum, the genera, including Blautia, Sellimonas and Ruminococcaceae UCG-014, exhibited significant age-related differences (p < 0.05), whereas other genera showed no significant variation (p > 0.05). Collectively, the bacterial community α-diversity, compositional structure and specific genus abundance in the jejunum, ileum and cecum of lambs demonstrated pronounced age-dependent variation and intestinal segment specificity patterns. This study provides a foundation for a deeper understanding of the succession patterns of the early digestive tract microbiota in lambs, and is conducive to the development of early nutrition strategies based on precise regulation of the microbiome. Full article

This study aimed to investigate the effects of dietary resveratrol supplementation on fermentation characteristics, microbial diversity, and community composition of feces from Hu sheep. A total of 20 three-month-old Hu sheep with similar body weights (20.62 ± 0.51 kg) were randomly divided into the control group (fed a basal diet, CON) and the treatment group (fed a basal diet supplemented with resveratrol at 100 mg/kg of feed, RES), with 10 sheep in each group, and lasted for 75 days. Feces were collected from each sheep at twenty-four time points for fecal fermentation characteristics determination and microbial analysis. The results showed that the pH value was higher in the RES group than in the CON group (p < 0.05), while the concentration of ammonia nitrogen was lower, showing a 10.6% reduction compared to the CON group (p = 0.013). The richness, Shannon index, and inverse Simpson index of fecal microbiota were higher in the CON group than in the RES group (p < 0.05). The relative abundances of Planctomycetota, Bacteroides, Alistipes, and NK4A214 group were higher in the CON group than in the RES group (p < 0.05). Additionally, the relative abundance of the glycan biosynthesis and metabolism pathway was higher in the CON group (p < 0.05). The relative abundance of Prevotella was lower in the CON group than in the RES group (p < 0.05). Principal co-ordinate analysis (PCoA) revealed no overlap between the two groups, and analysis of similarities (ANOSIM) showed significant differences between the CON and RES groups (R = 0.4560, p = 0.012). Linear discriminant analysis effect size (LEfSe) analysis identified 27 microbial biomarkers, with the RES group having more beneficial bacteria and the CON group having more potentially harmful bacteria. The study demonstrated that dietary resveratrol supplementation reduced the concentration of ammonia nitrogen in feces, decreased microbial diversity, and increased the abundance of beneficial bacteria. The findings of this research provide a post-digestion perspective for evaluating the application of resveratrol in ruminant production. Full article

Diet and gut microbiota are significant determinants of host health, but how dietary quality modulates gut microbiota in Blastocystis-colonised individuals remains underexplored. We studied two contrasting cohorts: university students (FACSA, n = 46) and institutionalised children with their caregivers (PAVILA, n = 37), representing distinct dietary and sociodemographic contexts. Eight participants from each cohort tested positive for Blastocystis; however, two PAVILA samples could not be sequenced, resulting in a final microbiota subcohort of 14 individuals (FACSA n = 8, PAVILA n = 6). Dietary quality was assessed using the Healthy Eating Index-2020 (HEI-2020), and faecal microbiota was characterised through 16S rRNA sequencing. Alpha and beta diversity were analysed, and genus-level transformed data were further evaluated using permutational multivariate analysis of variance (PERMANOVA), principal coordinates analysis (PCoA), and distance-based redundancy analysis (db-RDA). The FACSA cohort exhibited higher microbial richness and diversity (Shannon and Simpson indexes, p < 0.01) compared to PAVILA, with marked differences in microbial composition (PERMANOVA R² = 0.39, p = 0.002). Total diet quality correlated with microbial structure (R² = 0.26, p = 0.016), with protein (R² = 0.23, p = 0.017) and vegetable components (R² = 0.17, p = 0.044) as primary contributors. Multivariate analysis showed that higher protein and vegetable intakes were associated with genera such as Sellimonas, Murimonas, Alistipes, and Desulfovibrio (FACSA group). In contrast, Hydrogenoanaerobacterium, V9D2013_group, and Haemophilus were linked to lower-quality diets (PAVILA group). Our results indicate that diet quality significantly influences gut microbiota composition in individuals colonised by Blastocystis, underscoring its potential as a target for nutritional interventions in vulnerable populations. Full article

Understanding how elevation influences forest structure and species composition is crucial for effective conservation in mountainous regions like Nepal, where ecosystems change dramatically over short distances. This study assessed forest dynamics along an elevational gradient (600–3200 m) in Nepal’s mid-hills, incorporating elevational zonation (Tropical, Subtropical, Lower Temperate, and Upper Temperate) and aspect-driven variations. We established 27 square plots (20 × 20 m) at 100 m elevation intervals along a trekking route from Tallo Dungeshwor near the Karnali River to Mahabu Lek, recording all tree species with a diameter at breast height (DBH) ≥ 5 cm. Tree density across the elevational gradient ranged from 250 to 800 trees/ha. Basal area varied between 7.46 and 82.43 m²/ha, while mean tree height ranged from 6.89 to 16.62 m. Species diversity was assessed using the Shannon diversity index, and species dominance was evaluated through the Importance Value Index (IVI). Diversity peaked at mid-elevations, with Shorea robusta and Quercus semicarpifolia identified as dominant species. While minor variations occurred across topographic aspects, statistical analysis confirmed elevation as the dominant driver of forest structure and composition. Correlation analysis revealed a significant positive relationship between elevation and Simpson’s diversity index (r = 0.45, p < 0.05), indicating increased dominance diversity at higher elevations. These findings highlight the critical role of elevation and aspect in shaping forest ecosystems and offer valuable baseline data for climate-resilient management. We recommend conservation planning that is sensitive to topographic gradients, integrates long-term, climate-adaptive monitoring, and engages local communities to anticipate ecological shifts and address mounting anthropogenic pressures in vulnerable montane zones. Full article

The Dongting Lake wetland is an important habitat for rodents. In order to understand the structural characteristics of rodent communities and the effect of groundwater level on them, this study explored the changes in rodent community structure in four different habitats (Carex, Reeds, Carex + Reeds, and Poplar) from 2003 to 2023. Meanwhile, the relationships between groundwater level, nutrient composition of Carex brevicuspis, and structural characteristics of rodent communities were analyzed. The results showed that the advantages of rodent species in the four different habitats are different, and the community structure of rodents has undergone significant changes in recent years. A significant correlation between groundwater level and the nutrient composition of C. brevicuspis was found. Further analysis shows a significant correlation between the nutritional components of C. brevicuspis and the population structure of rodents. Crude protein, total phosphorus, and dry matter were three key plant nutrient indicators that were significantly correlated with both capture rate and the community diversity index (p < 0.05). Total phosphorus and crude protein were significantly negatively correlated with capture rate and Simpson’s index (p < 0.05), but significantly positively correlated with Pielou’s index and Shannon–Wiener’s index (p < 0.05), while the dry matter was completely opposite. The research conclusions suggest that different habitats and groundwater levels affect different characteristics of rodent community structures, and that plant nutrients are likely to be the mediator. Full article

The impact of long-term organic (ECO) versus conventional (CON) agricultural management on subsurface soil microbiota diversity and soil physicochemical properties remains unclear in Mediterranean vineyards. This study evaluated long-term ECO and CON effects in the Alt Penedès terroir (Spain), focusing on subsurface soil microbial diversity and soil characteristics. ECO increased the fungal-to-bacterial ratio and ammonium-oxidizing bacteria but reduced total subsurface soil bacterial populations and soil organic carbon. While ECO did not enhance annual yield production in the vineyard, fungal abundance, and ammonium-oxidizing archaea, it slightly increased the overall alpha diversity (Shannon and Inverse Simpson indexes) and significantly altered taxa composition in subsurface soil with a more robust and modular community. Crop management, soil texture, training system, and rootstock, but not vine variety, significantly influenced beta diversity in subsurface soil. The Mantel test revealed subsurface soil texture, Ca²⁺/Mg²⁺ ratio, and salinity as the main key soil drivers shifting the microbial community (beta diversity), while C/N and topsoil organic matter significantly correlated with bacterial abundance; NH₄⁺ correlated with fungal abundance; and N-Kjeldahl, pH, and Mg²⁺/K⁺ correlated with alpha diversity. Integrating soil microbiota and physicochemical monitoring allowed us to confirm the positive effect of long-term agroecological practices on subsurface soil health and to identify the critical factors shaping their microbial communities in Mediterranean vineyards. Full article

The stand structure of ancient tea tree (Camellia taliensis) communities is critical for maintaining their structural and functional stability. Therefore, this study employed backpack laser scanning (BLS) technology to extract individual tree parameters (diameter at breast height, tree height, relative coordinates, etc.) in seven sample plots (25 m × 25 m each) to analyze their spatial and non-spatial structure characteristics. Firstly, the accuracy of diameter at breast height (DBH) and tree height (TH) estimations using BLS resulted in a root mean square error (RMSE) of 4.247 cm and 2.736 m and a coefficient of determination (R²) of 0.948 and 0.614, respectively. Secondly, in this community, trees exhibited an aggregated spatial distribution (average uniform angle > 0.59), with small differences in DBH among adjacent trees (average dominance > 0.48) and a high proportion of adjacent trees belonging to different species (average mingling > 0.64). Ancient tea trees in the 5–15 cm diameter class face considerable competitive pressure, with values ranging from 14.28 to 179.03. Thirdly, this community exhibits rich species composition (more than 7 families, 8 genera, and 10 species, respectively), strong regeneration capacity (with an inverse J-shaped diameter distribution), uniform species distribution (Pielou evenness index > 0.71), and high species diversity (with a Shannon–Wiener diversity index ranging from 1.65 to 2.47 and a Simpson diversity index ranging from 0.71 to 0.91), and the ancient tea trees maintain a prominent dominant status and important value ranging from 19.36% to 49%. The results indicate that, under the current conditions, the structure and function of this community collectively exhibit relatively stable characteristics. BLS provides a powerful tool for the research and conservation of rare and endangered species. Full article

This paper proposes a new index, the “distribution non-uniformity index (DNUI)”, for quantitatively measuring the non-uniformity or unevenness of a probability distribution relative to a baseline uniform distribution. The proposed DNUI is a normalized, distance-based metric ranging between 0 and 1, with 0 indicating perfect uniformity and 1 indicating extreme non-uniformity. It satisfies our axioms for an effective non-uniformity index and is applicable to both discrete and continuous probability distributions. Several examples are presented to demonstrate its application and to compare it with two distance measures, namely, the Hellinger distance (HD) and the total variation distance (TVD), and two classical evenness measures, namely, Simpson’s evenness and Buzas and Gibson’s evenness. Full article