Search Results (104)

Understanding the processes that drive microbial community assembly is a fundamental question in ecology, with important implications for predicting community responses to environmental disturbances. River ecosystems are under growing pressure from human disturbances, jeopardizing their ecological functions. Here, we investigated bacterial and protistan communities along the Yujiang River using environmental DNA metabarcoding. Bacterial communities exhibited significantly greater alpha diversity and broader habitat niches compared to protists. Additionally, a negative correlation was found between alpha diversity and niche breadth for both groups. Protistan communities exhibited significantly higher beta diversity (Bray–Curtis distance) than bacterial communities, with species turnover being the principal factor driving the variations in both communities. Null model results indicated that heterogeneous selection primarily structured bacterial communities, while stochastic processes (drift) mainly governed protist communities. Redundancy analysis and Mantel tests showed significant associations between environmental factors (e.g., temperature and pH) and bacterial community composition. Moreover, the longitude of sampling sites was linked to spatial variations in both bacterial and protistan communities. Further analyses, including distance-decay patterns, variation partitioning, and multiple regression on distance matrices, demonstrated that bacterial communities were driven by both environmental and spatial factors, while protist communities exhibited a stronger response to spatial factors. These results enhance our understanding of microbial community assembly in river ecosystems and provide valuable insights for the conservation and sustainable management of freshwater systems. Full article

China has made a major strategic decision to build world-class universities and first-class disciplines (abbreviation: Double First-Class), aimed at enhancing the global competitiveness of Chinese higher education. Industry-specific universities have a special historical evolution and distinctive characteristics. China’s industry-specific universities have always played an important role in the higher education system and made significant contributions to the development of the country. However, the “Double First-Class” initiative presents both opportunities and challenges for industry-specific universities. This paper employs the SWOT analysis method to conduct a qualitative analysis of industry-specific universities and proposes a strategic matrix for decision-making. At the same time, from a niche perspective, this paper explores the sustainable development strategies of these institutions within the initiative through the calculation of niche breadth, niche overlap, and their relationship analysis. The research results indicate that the “Double First-Class” initiative has played a positive role in promoting the expansion of universities’ ecological niches. However, it has also led to excessive niche overlap and intense competition. Industry-specific universities face opportunities and challenges in terms of structure, strategy, and policy for their sustainable development. Key findings highlight the importance of strategic alignment with national demand, industry cooperation, and policy orientation for sustainable growth. This paper proposes recommendations for the construction of a sustainable development framework, implementation of strategic initiatives, and policy guidance for universities with industrial characteristics from three perspectives: government, industry, and universities. Full article

The Brazilian Amazon, a global biodiversity hotspot, faces escalating anthropogenic pressures and climate change, underscoring the urgent need to identify priority areas for ecological restoration and sustainable forest use. This study applied a topoclimatic zoning methodological framework in the Legal Amazon to evaluate the environmental suitability of 12 native tree species across anthropogenically altered landscapes. Species occurrence data were compiled from the RADAMBRASIL Project, GBIF, Herbaria, and forest inventory literature. Climatic, topographic, and geographic variables (1961–2022) informed the zoning model. Our findings reveal that species such as Dinizia excelsa Ducke (81%) and Handroanthus albus (Cham.) Mattos (78%) exhibit exceptionally high topoclimatic suitability. Conversely, Simarouba amara Aubl. (37%) and Schizolobium parahyba (Vell.) S.F.Blake var. amazonicum (Huber ex Ducke) Barneby (46%) showed the lowest proportions in high-potential areas, suggesting their greater ecological breadth or specific niche requirements in altered zones. Principal Component Analysis (PCA) indicated strong correlations between high-potential areas and Af3, Am3, and Aw4 climatic subtypes. This study offers a replicable, evidence-based model for prioritizing species and locations, significantly supporting sustainable silviculture and enhancing the long-term resilience of Amazonian forests in the face of climate change. Full article

The comparative analysis of the feeding ecology among sympatric small carnivores reveals both differentiation and overlap in resource utilization patterns, which serves as a critical pathway for understanding interspecific interactions and maintaining ecosystem stability. In this study, we collected fecal samples from sympatric Pallas’s cats (Otocolobus manul, n = 26) and red foxes (Vulpes vulpes, n = 13) within the Sanjiangyuan National Park (SNP) in China. Subsequently, DNA barcoding technology was employed to analyze the dietary composition and interspecific differences of these two small carnivores. The results demonstrated that both species primarily prey on plateau pikas (Ochotona curzoniae) and small rodents. Despite a high trophic niche overlap between Pallas’s cats and red foxes (O_jk = 0.81), interspecific competition is mitigated through differentiate feeding proportions of shared prey species. Furthermore, the trophic niche breadth of red foxes (B = 267.89) exceeds that of Pallas’s cats (B = 162.94), reflecting a greater diversity of prey resources utilized by red foxes. Consequently, the two small carnivores achieve sympatric coexistence via differentiated resource utilization. These findings enhance our understanding of the coexistence mechanisms within carnivore communities and provide a scientific basis for the conservation of wildlife in the SNP. Full article

Plant microbiomes provide significant fitness advantages to their plant hosts, especially in the sub-nival belt. Studies to date have primarily focused on belowground communities in this region. Here, we utilized high-throughput DNA sequencing to quantify bacterial communities in the rhizosphere soil as well as in the root and leaf endosphere compartments of Silene nigrescens to uncover the differentiation and interconnections of these bacterial communities along the soil-to-plant continuum. Our findings reveal that the bacterial communities exhibit notable variation across different plant compartment niches: the rhizosphere soil, root endosphere, and leaf endosphere. There was a progressive decline in diversity, network complexity, network modularity, and niche breadth from the rhizosphere soil to the root endosphere, and further to the leaf endosphere. Conversely, both the host plant selection effect and the stability of these communities showed an increasing trend. Total nitrogen and total potassium emerged as crucial factors accounting for the observed differences in diversity and composition, respectively. Additionally, 3.6% of the total amplicon sequence variants (ASVs) were shared across the rhizosphere soil, root endosphere, and leaf endosphere. Source-tracking analysis further revealed bacterial community migration among these compartments. The genera Pseudomonas, IMCC26256, Mycobacterium, Phyllobacterium, and Sphingomonas constituted the core of the bacterial microbiome. These taxa are shared across all three compartment niches and function as key connector species. Notably, Pseudomonas stands out as the predominant taxon among these bacteria, with nitrogen being the most significant factor influencing its relative abundance. These findings deepen our understanding of the assembly principles and ecological dynamics of the plant microbiome in the sub-nival belt, offering an integrated framework for its study. Full article

To explore the spatiotemporal niche characteristics and changing regularities of insect communities under lamps in a semi-arid region, this paper analyzed Levins’ niche breadth index and the Pianka niche overlap index of 10 orders and 19 selected common families or superfamilies of insect communities under lamps from April to September 2018 at six vegetation sites in the Habahu National Nature Reserve, a rare desert grassland–wetland reserve in China. The results indicated the following: (1) Different taxa possess varying spatiotemporal, temporal, and spatial niche breadths, suggesting that insects effectively utilized resources in the Habahu Nature Reserve. (2) Among these groups, in terms of the orders aspect, Lepidoptera had the largest temporal niche breadth, the Hemiptera had the largest spatial niche breadth, and Lepidoptera, Coleoptera, and Hemiptera had relatively large spatiotemporal niche breadths, while Odonata had the smallest niche breadth in all three aspects. The orders of Coleoptera and Lepidoptera had the largest spatiotemporal niche overlap value, while Odonata and Diptera had the smallest. (3) In terms of the common families (superfamilies) aspect, Noctuidae had the largest temporal niche breadth and spatiotemporal niche breadth, while Hydrophilidae had the smallest. The spatial niche breadth of Sphingidae was the largest, while Corixidae was the smallest. Noctuidae and Pyraloidea had the largest spatiotemporal niche overlap value among these herbivore groups, Miridae and Chrysopidae, among the herbivore to predatory groups, and Noctuidae and Braconidae, among the herbivore to parasitic groups. This lays a theoretical foundation for developing Chrysopidae and Braconidae as biological control taxa in the Habahu Nature Reserve. Full article

Exploring the diversity and community structure of darkling beetles (Tenebrionidae) and the associated environmental factors on an alluvial fan provides useful insights into the ecology of these landscape features. This study investigated Chaqikou in the Helan Mountains, which features unique alluvial fan landforms. Sample plots (200 × 200 m) were established at three positions: the fan top, fan middle, and fan edge. From May to October 2023, pitfall traps were used to survey beetle community composition and its relationship with environmental factors. Significant variations were observed in species composition and diversity indices across different months and sample plots. Strongly xerophilous species exhibited broader ecological niche breadth, while moderately xerophilous species tended to distribute in the mid-to-upper segments of alluvial fans. Non-metric multidimensional scaling analysis revealed temporal shifts in community composition, with beta diversity analysis showing that species nestedness dominated from June to August, while species replacement was prominent in May, September, and October. Redundancy analysis indicated that environmental factors affecting species distribution varied by plot. On the landscape scale, altitude was the primary factor affecting beetle distribution. Variance partitioning analysis showed that topographic, soil, and vegetation factors explained 51.7%, 20.2%, and 9.4% of the variation in the beetle community, respectively. It is evident that altitudinal gradients shape ecological filtering pressures by creating multidimensional heterogeneity in topography, soil properties, and vegetation coverage. The adaptive matching between Tenebrionid species’ biological traits and environmental factors ultimately governs the spatial distribution patterns of darkling beetle diversity in alluvial fan desert grasslands. Full article

The conversion of tropical forests into urban and agriculture landscapes may alter insect populations through habitat disturbance and impact the diets of aerial insectivores. Most dietary studies on aerial insectivores have limitation on identifying prey at higher taxonomic levels in broad landscapes, restricting species-level identification and thus making a detailed dietary comparison impossible. This study examines the dietary changes through adaptation of house-farm swiftlets (Aerodramus sp.) and Pacific swallows (Hirundo tahitica) across three distinct habitats in Peninsular Malaysia: mixed-use landscapes, oil palm plantations, and paddy fields. High-throughput DNA metabarcoding with ANML primers targeting mitochondrial CO1 gene, identified 245 arthropod prey species, with six dominant orders: Coleoptera, Diptera, Blattodea, Hemiptera, Hymenoptera, and Lepidoptera. Mixed-use landscapes supported the highest dietary diversity and niche breadth, reflecting their ecological complexity. Paddy fields exhibited moderate diversity, while oil palm plantations demonstrated the lowest diversity, influenced by simplified vegetation structures and limited prey availability. The consumption of agricultural pests and vector species highlights the critical ecological role of aerial insectivorous birds in natural pest management and mitigating vector-borne disease risks. This research emphasizes the importance of conserving habitat heterogeneity to sustain the ecological services provided by these birds, benefiting both agricultural productivity and public health. Full article

This study investigates the foraging habits and dietary niche characteristics of plateau pikas (Ochotona curzoniae) by analyzing differences between the cold and warm seasons using stable isotope analysis of carbon and nitrogen in liver, muscle, and fur organs. The results indicated that in the cold season, the plant species incorporated into different organs were more diverse than in the warm season, with varying contribution rates for each plant species. Potentilla anserina made the most significant contribution to the plateau pika’s diet during the cold season, while Kobresia humilis had the highest contribution in the warm season. The trophic niche width of liver and muscle organs was broader in the cold season compared to the warm season, while the trophic niche width of the fur organ was narrower in the cold season. Additionally, long-term dietary information derived from muscle and fur organs showed a wider niche breadth compared to short-term dietary information obtained from the liver organ. Across both seasons, organ niche overlap was highest in fur, followed by muscle, and lowest in the liver. In conclusion, short-term food source information (derived from the liver organ) indicated fewer food types and a smaller niche breadth. In contrast, long-term food source information (obtained from muscle and fur organs) included a greater variety of food types and a larger niche breadth. Additionally, niche overlap was more pronounced on the long-term scale compared to the short-term scale. These findings highlight the adaptive feeding strategies of plateau pikas in response to varying seasonal food availability and the ecological importance of their dietary flexibility in maintaining energy balance in challenging environments. Full article

The study of carnivores’ diets is an important conservation tool, which can minimize conflicts with different stakeholders and provide proper substantiations for management measures. The main aim of this study was to understand the diet of a small, isolated pack named Mogadouro Sul, present in the Northeast of Trás-os-Montes (Portugal). Scat analysis was the method used to determine what wolves consumed. The specific origin of all collected fecal samples (n = 78) was confirmed by molecular analysis. The results, expressed in frequency of occurrence (FO) showed that domestic animals were the most frequent food category in the wolf’s diet (78.3% FO), with a special incidence in goats (40.6% FO), although wild ungulates (roe deer and wild boar) also accounted for 21.7% FO of the diet. The study pack presented a diet diversity (H′) of 0.65 and a food niche breadth (B′) of 0.55. Food availability did not appear to be a limiting factor, and the wolf’s presence in the study area could be explained by changes in land use and increased infrastructure. This trophic behavior may threaten the conservation of this pack due to the persecution it may face. Full article

For 30 years (1992–2021), we collected pellets and pellet fragments and recorded prey cached in Snowy Owl (Bubo scandiacus) nests during the breeding season in Utqiaġvik, Alaska. About 14,000 pellets from an estimated 700 Snowy Owls yielded 43,689 prey items, while caches in 284 nests yielded 3334 prey items. The owls ate thirty-seven species of vertebrates: one species of fish, five species of mammals, and thirty-one species of birds. Based on the pellet analysis, lemmings represented 99.0% of the total prey, with brown lemmings (Lemmus trimucronatus) representing 94.6%, collared lemmings (Dicrostonyx groenlandicus) representing 3.1%, and unidentified lemmings representing 1.3%. All other species were <1%. Based on the prey cached in nests, lemmings represented about 90.0% (89.9%) of the total prey (n = 3334), with brown lemmings representing 88.0% (87.9%), collared lemmings representing 1.9%, and unidentified lemmings representing <1%. Birds represented only 10.0% of the prey cached in nests, although many species were eaten. Food niche breadth (FNB) and dietary evenness (DIEV) scores from pellets were narrow for the prey identified within a group or species. FNB and DIEV scores from the prey cached in nests were also narrow for the prey identified within a group or species. There was almost complete dietary overlap when comparing the prey from pellets with the prey from caches. Biomass estimates from brown lemmings (178 kg) cached in nests were 59 times more than those from collared lemmings (3 kg). Biomass estimates for large birds were misleading, as the owls mainly ate the breast, humerus, and femur muscles. Our study supports a general consensus that Snowy Owls are obligate lemming specialists during the breeding season in Utqiaġvik. In fact, they depend almost entirely on one species of lemming—the brown lemming. Consequently, anthropogenic or natural factors that impact lemming populations and distributions will directly affect Snowy Owl populations. Full article

This study presents a structured review of 59 academic articles, identified through an extensive literature survey, focused on the environmental implications of drone-based delivery systems within the broader fields of transportation, logistics, and sustainability. The reviewed journals cover a multidisciplinary range of topics, reflecting the intersection of drone technology with environmental science, logistics management, and operational research. Key journals, such as Transportation Research Part C: Emerging Technologies, Computers and Industrial Engineering, and Applied Mathematical Modelling, offer critical insights into how drone technology can reshape logistics systems, reduce environmental impacts, and contribute to intelligent transportation solutions. In addition, niche publications in areas like artificial intelligence, disaster risk reduction, and sustainable transportation further enhance the breadth of this review. By identifying and categorizing these publications, this review provides a valuable resource for researchers and practitioners aiming to explore the environmental and operational challenges of drone-based delivery systems, while also offering a foundation for future research on their sustainability and integration into existing logistics frameworks. Full article

Parasitic organisms, as an important component of ecosystems, have long been a focal point in ecological research, particularly concerning the relationship between their growth characteristics, ecological niche, and distribution patterns. This study selects the holoparasitic plant species Cuscuta campestris Yunck., Cuscuta australis R.Br., and Cuscuta chinensis Lam. from the Cuscuta subgenus Grammica as model species to explore the relationship between the growth rate, ecological niche breadth, and global distribution patterns of parasitic plants. Through greenhouse experiments and data analysis, the main findings of this study indicate a strong positive correlation between the growth rate, ecological niche breadth, number of global occurrence points, and global distribution area for C. campestris, C. australis, and C. chinensis. The significant correlation between growth rate and ecological niche breadth suggests that the intrinsic growth characteristics of parasitic plants may significantly influence their realized ecological niche. Furthermore, the experimental results show that when C. campestris, C. australis, and C. chinensis parasitize non-native hosts from the Americas, they produce greater biomass than when parasitizing native hosts from China. In conclusion, this study provides new support for ecological theories regarding species adaptability, distribution patterns, and environmental influences, and offers directions for future research. Full article

The Asiatic lion (Panthera leo leo), a flagship species of conservation significance, has expanded its range beyond the Gir protected areas into multi-use landscapes, including the coastal regions of Saurashtra, Gujarat, India. This study examines the dietary patterns of Asiatic lions in this unique coastal region. Using scat analysis, we identified the prey species consumed and quantified their contributions to the lions’ diet. Results indicate that the lions predominantly consumed wild prey, such as Boselaphus tragocamelus, Sus scrofa, and Axis axis, which together constituted 64% of their diet. Domestic prey contributed 31%. In terms of biomass, wild prey accounted for 70%, with Boselaphus tragocamelus alone contributing 51%. The dietary niche breadth, calculated using Levin’s index, was 0.36, suggesting a relatively specialized diet. This study underscores the importance of prey abundance and habitat structure in shaping lion predation patterns. Lions’ reliance on wild prey, particularly Boselaphus tragocamelus and Sus scrofa, highlights their crucial role in the coastal region. Additionally, the inclusion of domestic prey, such as feral cattle, may reflect their high availability and reduced anti-predator behaviors. These findings emphasize the need for robust prey population monitoring and habitat conservation to ensure the long-term survival of Asiatic lions in the coastal region. Full article

In nature, closely related species often exhibit diverse characteristics, challenging simplistic line interpretations of trait evolution. For these species, the evolutionary dynamics of one trait may differ markedly from another, with some traits evolving at a slower pace and others rapidly diversifying. In light of this complexity and concerning the phenomenon of trait relationships that escape line measurement, we introduce a novel general adaptive optimal regression model, grounded on polynomial relationships. This approach seeks to capture intricate patterns in trait evolution by considering them as continuous stochastic variables along a phylogenetic tree. Using polynomial functions, the model offers a holistic and comprehensive description of the traits of the studied species, accounting for both decreasing and increasing trends over evolutionary time. We propose two sets of optimal adaptive evolutionary polynomial regression models of $k^{th}$ order, named the Ornstein–Uhlenbeck Brownian Motion Polynomial (${\mathrm{OUBMP}}_k$) model and Ornstein–Uhlenbeck Ornstein–Uhlenbeck Polynomial (${\mathrm{OUOUP}}_k$) model, respectively. Assume that the main trait value $y_t$ is a random variable of the Ornstein–Uhlenbeck (OU) process and that its optimal adaptive value ${\theta }_t^y$ has a polynomial relationship with other traits $x_t$ for statistical modeling, where $x_t$ can be a random variable of Brownian motion (BM) or OU process. As analytical representations for the likelihood of the models are not feasible, we implement an approximate Bayesian computation (ABC) technique to assess the performance through simulation. We also plan to apply models to the empirical study using the two datasets: the longevity vs. fecundity in the Mediterranean nekton group, and the trophic niche breadth vs. body mass in carnivores in a European forest region. Full article