Search Results (1,596)

In recent years, the homogenization and fragmentation of agricultural landscapes have intensified, leading to a decline in epigaeic arthropods. Landscape heterogeneity is a core factor regulating biodiversity, encompassing two key dimensions: composition heterogeneity and spatial configuration heterogeneity. Both landscape composition and spatial configuration heterogeneity influence the distribution of epigaeic arthropods through independent and joint effects. However, quantitative evidence addressing their relative and combined influences remains limited. This study was conducted across 30 independent landscape units (1 km × 1 km) in Changtu County. Pitfall traps were deployed across different habitat types, with three traps per habitat. The proportion of semi-natural habitats was used as an indicator of landscape compositional heterogeneity, while multiple landscape metrics were used to characterize spatial configuration heterogeneity. The effects of landscape heterogeneity on epigaeic arthropods were evaluated using two response variables: activity density (mean number of individuals captured per trap) and diversity (effective number of species). Variance partitioning analysis (VPA) and Bioenv analysis were applied to explore their individual and joint effects on epigaeic arthropods. The results showed that higher landscape composition heterogeneity was associated with greater activity density of epigaeic arthropods, but no significant correlation was found with arthropod diversity. In terms of landscape spatial configuration, patch density (PD) and landscape division index (DIVISION) constituted the optimal model explaining the activity density of epigaeic arthropods, highlighting the importance of patch structure within landscapes. Furthermore, spatial configurational heterogeneity showed a stronger independent contribution than compositional heterogeneity, although their joint effect accounted for the largest proportion of explained variation. These findings provide a theoretical basis for landscape optimization and biodiversity conservation in intensive agricultural regions of Northeast China. Full article

The increasing demand for energy, the finite nature of fossil fuel resources, and the necessity to reduce greenhouse gas emissions have intensified research on renewable energy sources of plant origin. Among potential energy feedstocks, herbaceous biomass has attracted growing interest due to its high productivity, rapid growth, and widespread occurrence. The aim of this study was to evaluate the energy potential of select sedge species (Carex spp.) commonly occurring in Poland as an alternative to fossil fuels. Aboveground biomass of eight sedge species was collected from natural habitats located in the Warta River valley. Cellulose, lignin, holocellulose, hemicellulose, and ash content in the biomass was determined. In addition, key energy parameters, namely net calorific value and gross calorific value, were analyzed. Differences among species were assessed using one-way analysis of variance, while similarities were explored using hierarchical clustering methods. The results revealed significant interspecific variation in both chemical composition and energy properties. Most analyzed sedge species had favorable lignocellulosic composition and energy parameters comparable to those of woody biomass, particularly willow and poplar. In contrast, Carex riparia was distinguished by a high ash content and lower calorific values, limiting its suitability for energy applications. Overall, the findings indicate that select Carex species may represent a valuable renewable feedstock for energy production, especially in the context of local and decentralized biomass-based energy systems. Full article

Polluted mangroves are ecologically sensitive habitats that provide ecosystem services. In a selected polluted forest of Simaisma, viable aerobic, halophilic, and heterotrophic hydrocarbon-degrading bacterial strains were isolated from both rhizosphere and non-rhizosphere regions. The chemical composition of sediment showed a clear distinction between the rhizosphere and non-rhizosphere sites, as well as coastal and non-coastal sediments, as per Principal Component Analysis (PCA) clustering. Anthracene, an indicator of oil pollution, was present along with vanadium, another marker of oil pollution. Through selective enrichment cultures, a total of 25 hydrocarbon-degrading bacterial strains were isolated, including Lysinibacillus xylanilyticus, Bacillus cereus, Lysinibacillus sphaericus, Pseudomonas stutzeri, Acinetobacter calcoaceticus, and Staphylococcus warneri. To link the adaptation of bacteria to sediment chemistry, nine B. cereus strains were investigated using their MALDI-TOF MS protein profiles combined with their dendrogram. The relationship between protein profiles of B. cereus strains with their biosurfactant production capabilities was explained by a tanglogram. The tanglegram suggests that biosurfactant production is an important functional trait in B. cereus, but it is not consistently reflected in the overall protein profile. This suggests that bacterial adaptation in the polluted mangrove sediments may involve changes at multiple cellular levels, including metabolic activity and variation in protein expression profiles. These findings confirm the involvement of mangrove-associated bacteria in the sustainability of mangrove forests by promoting bioremediation of oil pollution, thereby protecting coastal ecosystems and their environmental and socio-economic aspects. Full article

Wild orchid populations are declining with intensified habitat fragmentation posing severe challenges to germplasm conservation. As an important ornamental Orchidaceae species, Cymbidium ensifolium has abundant germplasm resources and frequent natural and artificial hybridization. Long-term natural evolution and anthropogenic disturbance have led to complex genetic backgrounds and ambiguous phylogenetic relationships hindering accurate germplasm identification, elite resource excavation, and selective breeding. As a distinctive variety, Cymbidium ensifolium var. susin has great breeding potential. Clarifying its phenotypic and genetic characteristics is crucial for accelerating breeding progress. In this study, phenotypic determination, Hyper-seq reduced-representation genome sequencing, SNP/InDel genotyping, genetic diversity analysis, and core collection construction were used to evaluate the genetic diversity, population differentiation, and core germplasm screening of 13 Cymbidium ensifolium var. susin accessions. The results showed significant phenotypic differences and rich genetic variation among tested materials. Based on highly weighted floral traits, accessions were divided into three major phenotypic groups. At the molecular level, 963,239 SNP and 182,399 InDel loci were identified and mainly distributed in intergenic regions, followed by introns and exons. A phylogenetic tree was constructed from SNP loci combined with principal component and phenotypic clustering analyses. This study preliminarily clarified the genetic structure of pure-heart Cymbidium ensifolium var. susin, showing a distinct geographical pattern: “high consistency in Fujian and Guangdong; strong differentiation in Southwest China; and a transitional gradient in Central China”. Meanwhile, six core germplasm accessions were screened in this study, which provides a solid theoretical basis and material support for the conservation of pure-heart Cymbidium ensifolium var. susin accessions, variety improvement, hybrid parent selection, and molecular marker-assisted breeding. This is of great significance for promoting the innovation of Chinese orchid germplasm resources and the high-quality development of the industry. Full article

Wetland ecosystems have been a central focus of ecological research for an quite some time. Nevertheless, the degradation of wetland riparian zones has markedly accelerated due to anthropogenic activities, climate change, and habitat heterogeneity. The objective of this paper is to investigate the differences in functional traits of riparian plants under changing wetland environments on a karst plateau, as well as to elucidate the adaptive strategies of wetland plants across different habitats. This study examines the Caohai Wetland located on the Guizhou karst plateau, selecting the leaves of four dominant plant species (Phragmites australis, Onopordum acanthium, Galium odoratum, Paspalum distichum) in the Caohai Wetland lakeshore zone and analyzes the influence of soil factors on the variation of plant functional traits within the wetland riparian zone. The results reveal that: (1) significant differences exist in the functional traits of dominant plants in the riparian zones of karst plateau wetlands, with complex interrelationships among these traits; (2) the coefficients of variation for magnesium (Mg) and calcium (Ca) in the soil are notably high (79.53% and 67.21%, respectively), whereas soil oxidation-reduction potential (ORP) exhibits the lowest coefficient of variation (4.36%)—furthermore, the convergent variation in specific leaf area (SLA) and leaf dry matter content (LDMC) directly reflects the strong environmental filtering imposed by this habitat—and (3) redundancy analysis (RDA) indicates that leaf length (LL), specific leaf area (SLA), leaf area (LA), and plant carbon content (PCC) are particularly sensitive to environmental changes, while soil calcium (Ca), total nitrogen (TN), water-dispersible clay (WDR), soil organic matter (SOM), soil moisture content (SPMC), and total potassium (TK) constitute the principal soil factors influencing plant adaptive strategies in karst plateau wetlands. In conclusion, this study demonstrates that adaptation to karst wetland habitats is mediated through trade-offs in the allocation of photosynthetic products and the regulation of carbon (C), nitrogen (N), and phosphorus (P) nutrient balances under calcium-enriched and phosphorus-limited conditions, thereby reflecting the response characteristics of functional traits in karst plateau wetland plants to environmental changes. Full article

Background/Objectives: Environmental conditions in natural and cultivation-managed habitats strongly influence plant physiology and medicinal quality. However, the molecular mechanisms underlying metabolic differentiation in Anoectochilus roxburghii remain poorly understood. This study aimed to elucidate the metabolic and transcriptional differences between wild and cultivated A. roxburghii and to identify the regulatory mechanisms driving habitat-associated variation in metabolite profiles. Methods: We applied integrated non-targeted metabolomics and transcriptomics to compare metabolic profiles and gene expression in the leaves and stems of 15-month-old wild and cultivated A. roxburghii plants. Gene–metabolite correlation analysis was performed to identify coordinated correlation networks associated with key biosynthetic pathways. Results: Our analyses revealed clear differences in metabolite composition and transcriptional patterns between habitat types, suggesting distinct strategies of metabolic resource allocation. Wild plants showed significant enrichment of amino acids and other primary metabolites, whereas cultivated plants accumulated higher levels of flavonoids. Gene–metabolite correlation analysis indicated that multiple flavonoid metabolites were closely associated with key structural genes, including F3H, C12RT1, and HHT1, forming a tightly connected correlation network. In addition, several transcription factor families, including MYB, bHLH, WRKY, and AP2/ERF, showed strong correlations with genes involved in the flavonoid pathway, suggesting that flavonoid accumulation in cultivated plants may be associated with coordinated transcriptional control. Conclusions: Taken together, these findings suggest that habitat conditions are associated with differences in metabolic networks and resource allocation in A. roxburghii. This work provides new insight into the metabolic plasticity of this medicinal plant and highlights potential factors associated with molecular mechanisms that may contribute to variation in medicinal quality. Full article

Invasive polyphagous insects are an increasing concern in agricultural landscapes, particularly where forest and crop habitats occur in close proximity. The invasive planthopper Metcalfa pruinosa (Say, 1830) has expanded widely across Europe, yet its distribution across forest–crop interfaces remain insufficiently documented. This study examined the population dynamics of M. pruinosa along a forest–crop gradient in western Romania during the 2024–2025 growing seasons. Monitoring was conducted in a deciduous forest habitat and in adjacent crop systems located at increasing distances from the forest edge. In the forest habitat, adult abundance was consistently higher near the forest margin, while nymphs were recorded in the forest interior, indicating local development. In adjacent crop systems, both adult and nymph abundance showed a clear distance-dependent decline, with higher values recorded closer to the forest edge. Crop-level incidence and seasonal severity generally followed the same spatial pattern, with higher infestation levels in sites located nearer to the forest margin. These findings show a consistent spatial association between forest proximity and variation in M. pruinosa abundance and infestation levels across the forest–crop interface. Full article

Tiankeng ecosystems are characterized by strong microenvironmental gradients that influence plant adaptation; however, the molecular mechanisms underlying plant responses to altitudinal variation remain poorly understood. In this study, transcriptome sequencing and bioinformatic analyses were conducted to investigate the environmental adaptation mechanisms of three representative plant species (Hydrangea strigosa Rehder, Pilea martini, and Pilea sinofasciata) distributed along the vertical gradient of the Hanzhong Tiankeng in Shaanxi Province, China. Differential gene expression and functional enrichment analyses were performed to explore transcriptional responses under different altitude conditions. The results showed that flower coloration in Hydrangea strigosa Rehder was associated with the activation of sugar metabolism and triterpenoid biosynthesis pathways, suggesting potential indirect roles in modulating cellular metabolism and physiological conditions linked to flower coloration, while poor growth at the tiankeng bottom was associated with enhanced cellular respiration under low-light conditions, suggesting a potential link between energy metabolism and growth performance. In contrast, Pilea martini and Pilea sinofasciata exhibited better growth in the pit-bottom environment. Pilea martini promoted growth through enhanced carbohydrate metabolism and tricarboxylic acid cycle activity, whereas Pilea sinofasciata responded to environmental stress through hormone signaling, triterpenoid biosynthesis, and light signaling pathways. These findings reveal species-specific molecular strategies for plant adaptation to altitude-related environmental gradients in tiankeng ecosystems and provide insights into plant survival mechanisms in karst habitats. Full article

Background/Objectives: Eleocharis ussuriensis Zinserl. is a perennial riparian sedge widely distributed in Northeast Asia and a dominant component of freshwater vegetation in South Korea. However, the intraspecific genetic structure of this species across contrasting hydrological habitats remains insufficiently understood. This study aimed to develop novel SSR markers from whole-genome data and investigate genetic variation and population structure among E. ussuriensis populations in South Korea. Methods: Twenty-one novel simple sequence repeat (SSR) markers were developed from whole-genome sequence data and applied to analyze genetic variation in 120 individuals from 6 populations. Genetic diversity, differentiation, and gene flow were estimated using allele-frequency-based metrics, and population genetic structure was further evaluated using spatial information derived from geographic coordinates. Results: A total of 201 alleles were detected, with a mean polymorphism information content (PIC) of 0.759, indicating high marker informativeness. Mean genetic diversity across populations showed observed heterozygosity (Ho = 0.360) and expected heterozygosity (He = 0.281), while multilocus genotype ratios (G/N) ranged from 0.30 to 1.00 among populations. Genetic differentiation was substantial (F_ST = 0.373–0.669; Jost’s D = 0.540–0.997). Mantel tests revealed that genetic differentiation was significantly correlated with geographic distance (r = 0.67, p < 0.001). Both allele-frequency-based and spatially explicit approaches suggested genetic structuring among populations. Conclusions: The results suggest spatial tendencies in genetic structure among populations, reflecting patterns of allele distribution across regions. These findings provide baseline information on genetic variation in E. ussuriensis and may contribute to a better understanding of its ecological dynamics. Full article

As a key component of ecosystems, the synergistic relationship between wetland carbon storage and habitat quality is vital for maintaining ecological functions, and its evolution is profoundly influence by changes in wetlands. This study focuses on wetlands in western Jilin Province. Based on four sets of land use data from 2010 to 2023 and utilizing the InVEST model, combined with methods such as spatial autocorrelation, the Coupled Coordination Degree Model, and the GeoDetector, the study analyzed the co-variation of carbon storage and habitat quality, as well as their response to landscape patterns. The study found that between 2010 and 2023, the wetland area increased by a net 858.13 km², and landscape fragmentation was generally alleviated, although local connectivity continued to degrade. Regional carbon storage increased by 68.1%, totaling 7.43 × 10⁶ Mg, while the habitat quality index exhibited high spatiotemporal stability, fluctuating marginally between 0.609 and 0.621. Spatially, high-value areas remained primarily concentrated within nature reserves. Results of bivariate spatial autocorrelation analysis revealed a strengthening of spatial positive autocorrelation between carbon storage and habitat quality, with Moran’s I increasing from 0.410 to 0.501. The coupled coordination degree model further confirmed that the level of synergy between the two services exhibited a pattern of higher values in the north and lower values in the south, and that areas of high coordination expanded significantly outward following restoration projects. GeoDetector analysis indicates that the largest patch index is the core factor driving the synergistic development of ecosystem services. The results also suggest that the integrity of core wetland patches and a heterogeneous landscape pattern can promote the synergistic improvement of carbon storage and habitat quality through boundary effects and habitat complementarity. Full article

Triplophysa yarkandensis (Cypriniformes: Nemacheilidae), a rare endemic fish in the Tarim River Basin, Xinjiang, China, plays a pivotal role in maintaining the stability of plateau saline–alkaline aquatic ecosystems, yet its survival is increasingly threatened by habitat salinization. However, the multi-dimensional synergistic adaptation mechanisms linking its phenotypic variation, intestinal structure, and associated microbial communities to extreme saline–alkaline stress remain poorly understood. In this study, we innovatively integrated morphological/intestinal histological characterization, 16S rRNA gene sequencing, and microbial ecological analyses (co-occurrence networks and assembly processes) to systematically decode its adaptive strategies. Results revealed that T. yarkandensis exhibits a streamlined body shape, morphological variability, and elongated intestinal villi that may support locomotion and nutrient/ion uptake under osmotic stress. Its gut exerts a stringent selective filter, driving distinct differentiation between water and gut microbial communities—with gut-enriched core taxa (Aurantimicrobium and Aestuariivirga) and functional pathways (unsaturated fatty acid biosynthesis and ABC transporters) specialized for osmoregulation. Notably, the water microbial assembly is dominated by stochastic processes, while the gut assembly relies on host-driven deterministic selection, forming a habitat-specific adaptive pattern. These findings uncover the synergistic adaptation system of host phenotype and gut microbiota for survival in extreme saline–alkaline habitats, advancing our understanding of fish–microbe co-evolution in extreme ecosystems and providing critical theoretical support for the conservation of rare plateau fish, as well as guidance for the utilization of saline–alkaline water resources in aquaculture. Full article

Protected areas are often treated as internally homogeneous conservation units, yet their communities may be structured either as discrete modules or as continuous gradients shaped by environmental heterogeneity and human disturbance. Using camera-trap data from Liziping Nature Reserve, China, we examined the spatial organization of mammal and galliform bird communities and tested whether species-level environmental responses help explain community structure. From 109 camera-trap sites surveyed between October 2017 and July 2020, we obtained 6688 independent detections and retained 17 species for analysis. We combined β-diversity decomposition, clustering, NMDS ordination, single-species occupancy models, clustering of environmental response coefficients, and Mantel tests. Community variation was dominated by turnover rather than nestedness, and clustering based on co-occurrence and relative activity patterns did not reveal well-separated discrete modules. Instead, NMDS indicated continuous variation along environmental gradients, with elevation and vegetation productivity as the strongest correlates. Occupancy models showed marked species-specific environmental responses, especially to elevation, habitat structure, and human disturbance, and β-based clustering suggested two broad environmental response groups. Although human influences did not affect all species uniformly, some species showed clear sensitivity to recent disturbance and human-modified landscapes. These results indicate that communities in Liziping are better characterized as continuous gradient structures than as discrete modules, and suggest that conservation should emphasize the maintenance of environmental heterogeneity, habitat continuity, connectivity, and differentiated management of human activities within mountain protected areas. Full article

Morphological traits, as core components of functional traits, are fundamental in determining environmental adaptability. However, under climate warming, the adaptive morphological changes and associated ecological risks of locust populations migrating to higher altitudes remain poorly understood. Here, we investigated Calliptamus italicus, the dominant locust species in the desert steppes of the Ili River Basin, to explore the response patterns of its morphological functional traits along an altitudinal gradient and their relationships with environmental factors. Morphological measurements revealed that forewing area, width, and length, as well as hindwing width, exhibited highly significant positive correlations with altitude (p < 0.01); in contrast, body length, head width, head height, pronotum length, pronotum width, hind femur length, and hind tibia length displayed significant negative correlations with altitude (p < 0.05). All morphological indicators presented highly significant sexual dimorphism (p < 0.001). Ratio analysis showed that the pronotum width-to-head width ratio (M/C), pronotum height-to-head width ratio (H/C), and forewing length-to-hind tibia length ratio (E/F) were significantly positively correlated with the altitudinal gradient (p < 0.05), with all ratios exhibiting significant sexual differences (p < 0.05). Random Forest analysis showed that PC1 (75.5% of variation) reflected traits for feeding, jumping, and reproduction, whereas PC2 (5.6%) represented flight-related traits, with significant sexual dimorphism. This study demonstrates that trait variation in C. italicus along an altitudinal gradient is closely linked to environmental factors. Our findings provide critical data for predicting habitat adaptation responses in locust populations, thereby enhancing the precision and efficacy of locust plague management and contributing to the conservation and restoration of desert steppe ecosystems. Full article

Identifying the heterogeneous characteristics of habitat quality (HQ) trajectories is a key prerequisite for refined ecological spatial management. We used kernel Normalized Difference Vegetation Index (kNDVI) to correct the highly sensitive parameters, validated the correction results based on their consistency with the prior study findings, developed a framework for the evolution of HQ using Sen+MK and Pettitt’s tests, and utilized XGBoost and partial correlation analysis to identify the primary drivers of dynamic changes in HQ from both spatiotemporal perspectives. Our findings include the following: (1) between 2000 and 2023, the average annual rate of change in the HQ index was 0.0037 per year, indicating a continuous improvement in HQ. Compared with the period from 2011 to 2023 (0.0026 per year), the rate of improvement in HQ was faster during 2000–2011 (0.0047 per year). (2) Mutational improvement and progressive improvement were the main evolutionary trajectories, accounting for over 50.33% of the total. (3) Precipitation, land-use intensity (LUI), temperature, and elevation show a strong correlation with HQ distribution. The magnitude of HQ variation is related to HQ status, LUI, precipitation, and elevation. This study establishes a scientific foundation for developing differentiated regulatory strategies for YRB. Full article

Observations suggest that headwater streams have lower species diversity within a site than larger streams, but higher beta diversity, and thus gamma diversity, across a catchment. This pattern of diversity includes taxonomic richness and genetic diversity, as well as a high degree of endemism. I review several mechanisms that potentially contribute to the overall high diversity of freshwater organisms in headwaters, although these mechanisms are interdependent. These include the high numbers of headwater streams, heterogeneity of habitats and resources, founder effects, colonization dynamics, isolation, and strong selection, all leading to diversification of forms. However, riverscape diversity patterns vary across taxonomic and functional groups, highlighting that patterns of diversity are driven by different processes for different organisms. More explicitly structured sampling designs will better address patterns of taxonomic richness and for a broader range of taxa. It will be interesting to find ways to partition the relative importance of different mechanisms in contributing to the variation in diversity among headwaters. The great importance of headwater streams to global biodiversity conservation is clear, but will be more evident when better assessments of diversity patterns across these small systems are available. Full article