Plant diversity plays a crucial role in maintaining the stability of ecological function.Based on field investigations and experimental analyses,artificial grassland plots with varying sowing times,adjacent natural gr...Plant diversity plays a crucial role in maintaining the stability of ecological function.Based on field investigations and experimental analyses,artificial grassland plots with varying sowing times,adjacent natural grassland(CK),and open-pit coal mine dumps in the Muli mining area of Qinghai Province were selected as research subjects for this study.The characteristics of plant diversity and community stability were measured and analyzed,and the relationships between these factors and their influencing variables were evaluated.The results indicated significant differences in the vegetation community characteristics and plant diversity among the various grasslands.Coverage,aboveground biomass,belowground biomass,soil total nitrogen,and soil total carbon were the highest when the growth period was three years.Plant diversity and community stability in the natural grassland were significantly greater than that in the artificial grassland and open-pit coal mine dumps.A significant positive correlation was observed between plant diversity and community stability,suggesting that plant diversity can serve as an index of community stability.The order of stability,from highest to lowest,was CK>11a>10a>8a>9a>6a>7a>3a>2a>1a>0a.Years were identified as the primary factors affecting plant diversity and community stability by altering the soil pH.These results elucidate the relationships and driving mechanisms between plant diversity and community stability in grasslands,providing a scientific basis for maintaining community stability in artificial grassland ecosystems in alpine mining areas.展开更多
Herbaceous plants are an essential component of forest diversity and driver of ecosystem processes.However,because the growth forms and life-history strategies of herbaceous plants differ from those of woody plants,it...Herbaceous plants are an essential component of forest diversity and driver of ecosystem processes.However,because the growth forms and life-history strategies of herbaceous plants differ from those of woody plants,it is unclear whether the mechanisms that drive patterns plant diversity and community structure in these two plant groups are the same.In this study,we determined whether herb and woody plant communities have similar patterns and drivers of alpha-and beta-diversity.We compared species richness,distribution,and abundance of herbs to woody seedlings in a 20-ha Donglingshan warmtemperate forest(Donglingshan FDP),China.We also determined whether variation in patterns of species richness and composition are better explained by environmental or spatial variables.Herbaceous plants accounted for 72%of all species(81 herbaceous,31 woody)recorded.Alpha-and beta-diversity were higher in herbs than in woody seedlings.Although alpha-diversity of herbs and woody seedlings was not correlated across the site,the local-site contributions to beta-diversity for herbs and woody seedlings were negatively correlated.Habitat type explained slightly more variation in herb community composition than in woody seedling composition,with the highest diversity in the low-elevation slope.Environmental variables explained the variation in species richness and composition more in herbaceous plants than in woody seedlings.Our results indicate that different mechanisms drive variation in the herb and woody seedling communities,with herbs exhibiting greater environmental sensitivity and habitat dependence.These findings contribute to the better understanding of herbaceous plant diversity and composition in forest communities.展开更多
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang...Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.展开更多
An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month ...An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month period, identifying three species: R. quadrangulus, R. phoenicis, R. ferrugineus and a probable variant of R. phoenicis. Of these species, R. phoenicis stands out as the most widespread palm weevil, while the probable variant of R. phoenicis is considered the rarest subspecies in the Maniema region. The color of the head and elytra is a criterion for distinguishing the different species of Rhynchophorus spp. Morphological criteria indicate that the probable subspecies of R. phoenicis is the largest palm weevil in the Maniema region and even globally. It is followed by R. quadrangulus and, by far, by R. phoenicis. The smallest palm weevil in Maniema is R. ferrugineus. Moreover, these criteria reveal that, for all three species identified, the female is generally larger than the male. This study has the merit of extending the distribution of R. ferrugineus from the Maghreb to the central East of the DRC, and highlighting a subspecies of R. phoenicis. Recognition of the sexes on the basis of the shape of the tip of the abdomen (oval in the male and flat in the female) is an additional contribution.展开更多
Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highli...Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management.展开更多
Urban and peri-urban forests and trees play an important role by providing ecosystem services. Vegetation in sacred and cult places is among the useful forests and trees, but their characteristics are not well-documen...Urban and peri-urban forests and trees play an important role by providing ecosystem services. Vegetation in sacred and cult places is among the useful forests and trees, but their characteristics are not well-documented. It’s necessary to assess the potential of biodiversity conservation in sacred and cult places. This research aimed to enhance knowledge of the woody diversity in cult places in Ziguinchor. To achieve this, woody vegetation surveys were conducted to determine floristic composition and, diversity and structural parameters of woody vegetation. A total of 89 species belonging to 71 genera and 33 families were recorded, Fabaceae and Moraceae dominated in cemeteries and parishes, while Arecaceae and Euphorbiaceae were prevalent in mosques. Tree diversity varied according to cult places. Parishes recorded significatively higher diversity (2.2 ± 0.18) than cemeteries (1.59 ± 0.13) and mosques (1.07 ± 0.36). Cult places inflenced significatly the structural parameters. Tree density was higher in cemeteries (482.26 ± 302.71 indiv/ha) compared to parishes (197.61 ± 67.14 indiv/ha) and mosques (32.34 ± 4.89 indiv/ha). Mosques were characterized by higher canopy cover (25.43 ± 11.65 m2/ha), larger (83.72 ± 20.09 cm) and taller (16.28 ± 1.28 m) trees. Natural regeneration was also strongest in cemeteries (91.69% ± 3.715%), followed by parishes (62.22% ± 8.56%) and mosques (38.82% ± 14.5%). The cult places play an important ecological role in biodiversity conservation in urban and peri-urban areas.展开更多
The utilization of palynological data for plant diversity reconstructions offers notable advantages in addressing the discontinuity of plant fossils in the stratigraphic record.However,additional studies of modern pro...The utilization of palynological data for plant diversity reconstructions offers notable advantages in addressing the discontinuity of plant fossils in the stratigraphic record.However,additional studies of modern processes are required to validate or refine the accuracy of diversity results obtained from palynological data.In this study,we used a modern pollen dataset of China to compare the accuracy of plant diversity reconstructions using five different palynological diversity indices(i.e.,the pollen species number,BergereParker index,Simpson diversity index,Hill index,and ShannoneWiener index)over a large spatial scale.We then identified climate factors that are most strongly correlated with these patterns of plant diversity.We found that the index that most accurately reflects plant diversity is the ShannoneWiener index.Our analyses indicated that the most effective indices at reflecting plant diversity are the ShannoneWiener index and BergereParker index.Numerical analysis revealed that palynological diversity(measured using the ShannoneWiener index)was strongly correlated with climatic parameters,in particular average temperature in the coldest month and annual precipitation,suggesting these factors may be primary determinants of plant diversity distribution.We also found that a threshold value of the normalized ShannoneWiener index(NH=0.4)approximately aligns with the contour line specifying 400 mm annual precipitation,serving as a rudimentary indicator for assessing plant diversity in arid versus humid climates.This study suggests that pollen diversity indices have remarkable potential for quantitatively reconstructing paleoclimatic parameters.展开更多
Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored varia...Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change.展开更多
Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta div...Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta diversity we concerned.To obtain a comprehensive understanding of assemblage dissimilarity and its implications for biodiversity conservation in the Himalayas,we explored the elevational patterns and determinants of beta diversity and its turnover and nestedness components of pairwise and multiple types and taxonomic and phylogenetic dimensions simultaneously.Patterns of beta diversity and their components of different types and dimensions were calculated based on 96 sampling quadrats along an 1800-5400 m elevational gradient.We examined whether and how these patterns differed from random expectations using null models.Furthermore,we used random forest methods to quantify the role of environmental variables representing climate,topography,and human disturbance in determining these patterns.We found that beta diversity and its turnover component,regardless of its types and dimensions,shown a hump-shaped elevational patterns.Both pairwise and multiple phylogenetic beta diversity were remarkably lower than their taxonomic counterpart.These patterns were significantly less than random expectation and were mostly associated with climate variables.In summary,our results suggested that assemblage dissimilarity of seed plants was mostly originate from the replacement of closely related species determined by climate-driven environmental filtering.Accordingly,conservation efforts should better cover elevations with different climate types to maximalize biodiversity conservation,rather than only focus on elevations with highest species richness.Our study demonstrated that comparisons of beta diversity of different types,dimensions,and components could be conductive to consensus on the origin and mechanism of assemblage dissimilarity.展开更多
Collaborative forest management (CFM) is a form of forest governance in which local communities are involved in the management and decision-making processes related to forest resources. It is believed that forests und...Collaborative forest management (CFM) is a form of forest governance in which local communities are involved in the management and decision-making processes related to forest resources. It is believed that forests under such management are better in tree diversity and conservation status and thus hold more carbon stocks. The study assessed the impact of CFM on carbon stocks, tree species diversity & tree species density in Mabira Central Forest Reserve. Data were collected from plots that were systematically laid in the different purposively selected forest areas. The study findings show that there is no difference in stem density and carbon stocks between CFM and non-CFM areas. CFM areas had lower species richness compared to non-CFM areas. CFM areas, however, exhibited more species diversity than non-CFM areas. Climax colonization may favor a few dominant species over others, hence lowering species diversity despite the number of species being many in the understory, hence at the same time increasing species richness. Likewise, disturbance in CFM area may affect natural colonization and favor the emergency of many species either naturally or through assisted regeneration by reforestation, hence increasing diversity, whereas artificial selection of preferred species through harvesting may lower species richness, as observed. Recommendations for improving collaborative forest management (CFM) areas include implementing targeted interventions to enhance carbon sequestration, such as promoting reforestation and afforestation with high-carbon-storing species and strengthening monitoring and evaluation frameworks to assess carbon stock changes over time. Additionally, efforts should focus on enhancing biodiversity conservation by implementing more stringent protection measures and reducing human disturbance while encouraging community participation in biodiversity monitoring and conservation education.展开更多
Coastal ecosystems are plagued by high levels of microplastic pollution.Conducting baseline surveys is crucial to comprehend the distribution and influencing factors of this pollution.The present study investigates th...Coastal ecosystems are plagued by high levels of microplastic pollution.Conducting baseline surveys is crucial to comprehend the distribution and influencing factors of this pollution.The present study investigates the spatiotemporal variation and diversity of microplastic on the coastal beaches in Xiamen City,China,considering the combined effects of seasons,human activities,and physicochemical properties of sediments.It is detected that the abundance of microplastics in Xiamen beaches was 0.271±0.01 items/g.The abundance of microplastics in dry season was significantly higher than in rainy season.In terms of spatial variation,the beaches that attracted a larger number of tourists exhibited significantly higher microplastic abundance.The temporal pattern of microplastic distribution on different beaches varied greatly due to region-specific human activities(e.g.,mangrove restoration project)and sedimentary properties(e.g.,bulk density).When the assemblage of microplastics in the coastal area was viewed as a biological community,the Shannon-Wiener index and Pielou's index were higher in rainy season and in the beaches with high intensity of tourist activities,which suggests that the human activities and the surface runoff may contribute to the diversity of microplastics on coastal beaches.Future investigations are encouraged to combine controlled experiments and long-term monitoring at multiple scales to elucidate the underlying mechanisms and factors associated with microplastic pollution in coastal zone.展开更多
[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were invest...[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were investigated for the first time to analyze the species diversity characteristics of wood-decaying fungi in this area. This analysis was conducted through a comprehensive 5-year field investigation and systematic identification process. [Results] The wood-decaying fungi exhibited a distinctive species composition and distribution pattern within karst habitats, encompassing significant groups such as Polyporaceae and Hymenochaetaceae. Furthermore, these fungi demonstrated varying functional characteristics across the two ecological types of standing tree decay and wood decay. It was observed that wood-decaying fungi had a significant impact on the material cycle within karst ecosystems by degrading lignin and cellulose. Furthermore, the distribution of species diversity was closely associated with the characteristics of karst geomorphology and the types of vegetation. [Conclusions] This study not only addresses the lack of background data regarding wood-decaying fungi resources in karst regions, but also elucidates the maintenance mechanisms of fragile ecosystems from the perspective of decomposers. It provides a scientific foundation for biodiversity conservation, the prevention and control of forest diseases, and sustainable ecological management in karst regions.展开更多
Wetland degradation is an escalating global challenge with profound impacts on animal diversity,particularly during successional processes.Birds,as highly mobile and environmentally sensitive organisms,serve as effect...Wetland degradation is an escalating global challenge with profound impacts on animal diversity,particularly during successional processes.Birds,as highly mobile and environmentally sensitive organisms,serve as effective indicators of ecological change.While previous studies have primarily focused on local community structures and species diversity during a specific season,there is a need to extend the research timeframe and explore broader spatial variations.Additionally,expanding from simple species diversity indices to more multidimensional diversity indices would provide a more comprehensive understanding of wetland health and resilience.To address these gaps,we investigated the effects of wetland degradation on bird diversity across taxonomic,phylogenetic,and functional dimensions in the Zoige Wetland,a plateau meadow wetland biodiversity hotspot.Surveys were conducted during both breeding(summer)and overwintering(winter)seasons across 20 transects in 5 sampling areas,representing 4 degradation levels(pristine,low,medium,and high).Our study recorded a total of 106 bird species from 32 families and 14 orders,revealing distinct seasonal patterns in bird community composition and diversity.Biodiversity indices were significantly higher in pristine and low-degraded wetlands,particularly benefiting waterfowl(Anseriformes,Ciconiiformes)and wading birds(Charadriiformes)in winter,when these areas provided superior food resources and habitat conditions.In contrast,medium and highly degraded wetlands supported increased numbers of terrestrial birds(Passeriformes)and raptors(Accipitriformes,Falconiformes).Seasonal differences in taxonomic,phylogenetic,and functional diversity indices highlighted the contrasting ecological roles of wetlands during breeding and overwintering periods.Furthermore,indicator species analysis revealed key species associated with specific degradation levels and seasons,providing valuable insights into wetland health.This study underscores the importance of spatiotemporal dynamics in understanding avian responses to wetland degradation.By linking seasonal patterns of bird diversity to habitat conditions,our findings contribute to conservation efforts and provide a framework for assessing wetland degradation and its ecological impacts.展开更多
Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed,using various methods including at-sea fisheries resource surveys,fishing port surveys,underwater survey techniques,and data from literature,books...Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed,using various methods including at-sea fisheries resource surveys,fishing port surveys,underwater survey techniques,and data from literature,books,and databases,from which 1059 fish species across 40 orders,166 families,and 503 genera were identified.Among them,Acanthuriformes displayed the highest diversity,followed by Carangiformes and Perciformes.Notably,eight alien species were found in the Beibu Gulf.The International Union for Conservation of Nature(IUCN)Red List assessment revealed 51threatened species,primarily cartilaginous fish.Taxonomic changes affected 88.70%of species due to classification adjustments,misidentifications,and junior synonymy.This study contributed new data of the gulf,including one additional order,six new families,34 new genera,and 81 new species,emphasizing the dynamic nature of marine ecosystems.Fish diversity in the gulf was relatively lower than the broader South China Sea,attributed to limited habitats and survey methods.Different survey methods,such as gill nets,trap nets,and underwater cameras,yielded varying results.Ocean currents may have transported deep-sea species into the Beibu Gulf,leading to accidental records.Research gaps exist in unexplored areas,warranting further investigation.Therefore,the Beibu Gulf hosts significant marine biodiversity,but taxonomic challenges and undiscovered species require new research and conservation efforts.展开更多
Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity le...Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_(h)),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties.展开更多
Background Mobile element variants(MEVs)have a significant and complex impact on genomic diversity and phe-notypic traits.However,the quantity,distribution,and relationship with gene expression and complex traits of M...Background Mobile element variants(MEVs)have a significant and complex impact on genomic diversity and phe-notypic traits.However,the quantity,distribution,and relationship with gene expression and complex traits of MEVs in the pig genome remain poorly understood.Results We constructed the most comprehensive porcine MEV library based on high-depth whole genome sequencing(WGS)data from 747 pigs across 59 breeds worldwide.This database identified a total of 147,993 poly-morphic MEVs,including 121,099 short interspersed nuclear elements(SINEs),26,053 long interspersed nuclear elements(LINEs),802 long terminal repeats(LTRs),and 39 other transposons,among which 54%are newly discovered.We found that MEVs are unevenly distributed across the genome and are strongly influenced by negative selec-tion effects.Importantly,we identified 514,530,and 584 candidate MEVs associated with population differentiation,domestication,and breed formation,respectively.For example,a significantly differentiated MEV is located in the ATRX intron between Asian and European pigs,whereas ATRX is also differentially expressed between Asian and European pigs in muscle tissue.In addition,we identified 4,169 expressed MEVs(eMEVs)significantly associated with gene expression and 6,914 splicing MEVs(sMEVs)associated with gene splicing based on RNA-seq data from 266 porcine liver tissues.These eMEVs and sMEVs explain 6.24%and 9.47%,respectively,of the observed cis-heritability and high-light the important role of MEVs in the regulation of gene expression.Finally,we provide a high-quality SNP–MEV reference haplotype panel to impute MEV genotypes from genome-wide SNPs.Notably,we identified a candidate MEV significantly associated with total teat number,demonstrating the functionality of this reference panel.Conclusions The present investigation demonstrated the importance of MEVs in pigs in terms of population diversity,gene expression and phenotypic traits,which may provide useful resources and theoretical support for pig genetics and breeding.展开更多
Patterns and drivers of species–genetic diversity correlations(SGDCs)have been broadly examined across taxa and ecosystems and greatly deepen our understanding of how biodiversity is maintained.However,few studies ha...Patterns and drivers of species–genetic diversity correlations(SGDCs)have been broadly examined across taxa and ecosystems and greatly deepen our understanding of how biodiversity is maintained.However,few studies have examined the role of canopy structural heterogeneity,which is a defining feature of forests,in shaping SGDCs.Here,we determine what factors contribute toα-andβ-species–genetic diversity correlations(i.e.,α-andβ-SGDCs)in a Chinese subtropical forest.For this purpose,we used neutral molecular markers to assess genetic variation in almost all adult individuals of the dominant tree species,Lithocarpus xylocarpus,across plots in the Ailaoshan National Natural Reserve.We also quantified microhabitat variation by quantifying canopy structure heterogeneity with airborne laser scanning on 201-ha subtropical forest plots.We found that speciesα-diversity was negatively correlated with geneticα-diversity.Canopy structural heterogeneity was positively correlated with speciesα-diversity but negatively correlated with geneticα-diversity.These contrasting effects contributed to the formation of a negativeα-SGDC.Further,we found that canopy structural heterogeneity increases speciesα-diversity and decreases geneticα-diversity by reducing the population size of target species.Speciesβ-diversity,in contrast,was positively correlated with geneticβ-diversity.Differences in canopy structural heterogeneity between plots had non-linear parallel effects on the two levels ofβ-diversity,while geographic distance had a relatively weak effect onβ-SGDC.Our study indicates that canopy structural heterogeneity simultaneously affects plot-level community species diversity and population genetic diversity,and species and genetic turnover across plots,thus drivingα-andβ-SGDCs.展开更多
Latitudinal patterns of treeβ-diversity reveal important insights into the biogeographical processes that influence forest ecosystems.Although previous studies have extensively documentedβ-diversity within relativel...Latitudinal patterns of treeβ-diversity reveal important insights into the biogeographical processes that influence forest ecosystems.Although previous studies have extensively documentedβ-diversity within relatively small spatial extents,the potential drivers ofβ-diversity along latitudinal gradients are still not well understood at larger spatial extents.In this study,we determined whether treeβ-diversity is correlated with latitude in forests of southeastern China,and if so,what ecological processes contribute to these patterns of treeβ-diversity.We specifically aimed to disentangle the relative contributions from interspecific aggregation and environmental filtering across various spatial extents.We delineated regional communities comprising multiple nearby national forest inventory(NFI)plots around random focal plots.The number of NFI plots in a regional community served as a surrogate for spatial extent.We also used a null model to simulate randomly assembled communities and quantify the deviation(β-deviation)between observed and expectedβ-diversity.We found thatβ-diversity decreased along a latitudinal gradient and that this pattern was clearer at larger spatial extents.In addition,latitudinal patterns ofβ-deviation were explained by the degree of species spatial aggregation.We also identified environmental factors that driveβ-deviation in these forests,including precipitation,seasonality,and temperature variation.At larger spatial extents,these environmental variables explained up to 84%of theβ-deviation.Our results reinforce that ecological processes are scale-dependent and collectively contribute to theβ-gradient in subtropical forests.We recommend that conservation efforts maintain diverse forests and heterogeneous environments at multiple spatial extents to mitigate the adverse effects of climate change.展开更多
BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both...BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both mother and baby.AIM To investigate the relationships between FI and pregnancy outcomes,particularly GDM and PIH,while also examining the mediating role of the dietary diversity score(DDS).METHODS A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant women.Participants were women aged 18 years or older who provided complete data on FI and pregnancy outcomes.The FI was measured via the Household Food Security Survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/L.The DDS is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between FI and PIH,and GDM.RESULTS Seventeen percent of participants reported experiencing FI during pregnancy.The study found a significant association between FI and an elevated risk of GDM[odds ratio(OR)=3.32,95%CI:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PIH(OR=0.10,95%CI:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth weight.The FI wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBS),low-density lipoprotein cholesterol,and triglyceride levels.Our results indicate that the DDS acts as a significant mediator in the relationship between FI and the incidence of GDM.In particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDS(P=0.002).CONCLUSION These findings underscore the serious challenges that FI presents during pregnancy and its effects on maternal and infant health.Additionally,the study explored how DDS mediates the relationship between FI and the incidence of GDM.展开更多
This study explores the impact of board diversity on firm performance,with a focus on companies listed on the Singapore Stock Exchange(SGX).Board diversity is examined across various dimensions,including gender,age,et...This study explores the impact of board diversity on firm performance,with a focus on companies listed on the Singapore Stock Exchange(SGX).Board diversity is examined across various dimensions,including gender,age,ethnicity,and professional background,to understand its relationship with key performance indicators such as Return on Assets(ROA)and Return on Equity(ROE).Using a quantitative research approach,the study analyzes data from 90 publicly listed firms,employing descriptive statistics,correlation analysis,and multiple regression techniques.The findings reveal that the direct correlation between board diversity and financial performance,particularly in terms of ROA and ROE,is not statistically significant in the studied sample.Despite the lack of direct significance,the research underscores the nuanced and multifaceted role of diversity in corporate governance,suggesting that its impact may be more complex and influenced by various contextual factors.The study concludes by recommending that companies continue to enhance gender diversity,balance age structures,tailor professional backgrounds to industry needs,and manage board tenure effectively to optimize corporate governance and support sustainable growth.展开更多
基金financial support provided by the Research and Application Demonstration of Native Ecological Grass Seed Breeding Technology in“Black Soil Beaches”(2024-SF-101)。
文摘Plant diversity plays a crucial role in maintaining the stability of ecological function.Based on field investigations and experimental analyses,artificial grassland plots with varying sowing times,adjacent natural grassland(CK),and open-pit coal mine dumps in the Muli mining area of Qinghai Province were selected as research subjects for this study.The characteristics of plant diversity and community stability were measured and analyzed,and the relationships between these factors and their influencing variables were evaluated.The results indicated significant differences in the vegetation community characteristics and plant diversity among the various grasslands.Coverage,aboveground biomass,belowground biomass,soil total nitrogen,and soil total carbon were the highest when the growth period was three years.Plant diversity and community stability in the natural grassland were significantly greater than that in the artificial grassland and open-pit coal mine dumps.A significant positive correlation was observed between plant diversity and community stability,suggesting that plant diversity can serve as an index of community stability.The order of stability,from highest to lowest,was CK>11a>10a>8a>9a>6a>7a>3a>2a>1a>0a.Years were identified as the primary factors affecting plant diversity and community stability by altering the soil pH.These results elucidate the relationships and driving mechanisms between plant diversity and community stability in grasslands,providing a scientific basis for maintaining community stability in artificial grassland ecosystems in alpine mining areas.
基金financially supported by the NSF of China(3227161431870408)+3 种基金Biological Resources Programme,Chinese Academy of SciencesState Key Laboratory of Vegetation and Environmental Change of China(Y7206F1016)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31030000)National key basic R&D program of China(2017YFA0605100).
文摘Herbaceous plants are an essential component of forest diversity and driver of ecosystem processes.However,because the growth forms and life-history strategies of herbaceous plants differ from those of woody plants,it is unclear whether the mechanisms that drive patterns plant diversity and community structure in these two plant groups are the same.In this study,we determined whether herb and woody plant communities have similar patterns and drivers of alpha-and beta-diversity.We compared species richness,distribution,and abundance of herbs to woody seedlings in a 20-ha Donglingshan warmtemperate forest(Donglingshan FDP),China.We also determined whether variation in patterns of species richness and composition are better explained by environmental or spatial variables.Herbaceous plants accounted for 72%of all species(81 herbaceous,31 woody)recorded.Alpha-and beta-diversity were higher in herbs than in woody seedlings.Although alpha-diversity of herbs and woody seedlings was not correlated across the site,the local-site contributions to beta-diversity for herbs and woody seedlings were negatively correlated.Habitat type explained slightly more variation in herb community composition than in woody seedling composition,with the highest diversity in the low-elevation slope.Environmental variables explained the variation in species richness and composition more in herbaceous plants than in woody seedlings.Our results indicate that different mechanisms drive variation in the herb and woody seedling communities,with herbs exhibiting greater environmental sensitivity and habitat dependence.These findings contribute to the better understanding of herbaceous plant diversity and composition in forest communities.
基金funded by the Guangxi Natural Science Foundation Program (2022GXNSFAA035583 and 2020GXNSFAA159108)National Natural Science Foundation of China (32060305)+2 种基金Foundation of Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University)Ministry of Education, China (ERESEP 2021Z06)Chinese Forest Biodiversity Monitoring Network
文摘Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.
文摘An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month period, identifying three species: R. quadrangulus, R. phoenicis, R. ferrugineus and a probable variant of R. phoenicis. Of these species, R. phoenicis stands out as the most widespread palm weevil, while the probable variant of R. phoenicis is considered the rarest subspecies in the Maniema region. The color of the head and elytra is a criterion for distinguishing the different species of Rhynchophorus spp. Morphological criteria indicate that the probable subspecies of R. phoenicis is the largest palm weevil in the Maniema region and even globally. It is followed by R. quadrangulus and, by far, by R. phoenicis. The smallest palm weevil in Maniema is R. ferrugineus. Moreover, these criteria reveal that, for all three species identified, the female is generally larger than the male. This study has the merit of extending the distribution of R. ferrugineus from the Maghreb to the central East of the DRC, and highlighting a subspecies of R. phoenicis. Recognition of the sexes on the basis of the shape of the tip of the abdomen (oval in the male and flat in the female) is an additional contribution.
文摘Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management.
文摘Urban and peri-urban forests and trees play an important role by providing ecosystem services. Vegetation in sacred and cult places is among the useful forests and trees, but their characteristics are not well-documented. It’s necessary to assess the potential of biodiversity conservation in sacred and cult places. This research aimed to enhance knowledge of the woody diversity in cult places in Ziguinchor. To achieve this, woody vegetation surveys were conducted to determine floristic composition and, diversity and structural parameters of woody vegetation. A total of 89 species belonging to 71 genera and 33 families were recorded, Fabaceae and Moraceae dominated in cemeteries and parishes, while Arecaceae and Euphorbiaceae were prevalent in mosques. Tree diversity varied according to cult places. Parishes recorded significatively higher diversity (2.2 ± 0.18) than cemeteries (1.59 ± 0.13) and mosques (1.07 ± 0.36). Cult places inflenced significatly the structural parameters. Tree density was higher in cemeteries (482.26 ± 302.71 indiv/ha) compared to parishes (197.61 ± 67.14 indiv/ha) and mosques (32.34 ± 4.89 indiv/ha). Mosques were characterized by higher canopy cover (25.43 ± 11.65 m2/ha), larger (83.72 ± 20.09 cm) and taller (16.28 ± 1.28 m) trees. Natural regeneration was also strongest in cemeteries (91.69% ± 3.715%), followed by parishes (62.22% ± 8.56%) and mosques (38.82% ± 14.5%). The cult places play an important ecological role in biodiversity conservation in urban and peri-urban areas.
基金co-supported by the National Key Research and Development Program of China(2022YFF0800800)the National Natural Science Foundation of China(41988101-01,42130205)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0707)。
文摘The utilization of palynological data for plant diversity reconstructions offers notable advantages in addressing the discontinuity of plant fossils in the stratigraphic record.However,additional studies of modern processes are required to validate or refine the accuracy of diversity results obtained from palynological data.In this study,we used a modern pollen dataset of China to compare the accuracy of plant diversity reconstructions using five different palynological diversity indices(i.e.,the pollen species number,BergereParker index,Simpson diversity index,Hill index,and ShannoneWiener index)over a large spatial scale.We then identified climate factors that are most strongly correlated with these patterns of plant diversity.We found that the index that most accurately reflects plant diversity is the ShannoneWiener index.Our analyses indicated that the most effective indices at reflecting plant diversity are the ShannoneWiener index and BergereParker index.Numerical analysis revealed that palynological diversity(measured using the ShannoneWiener index)was strongly correlated with climatic parameters,in particular average temperature in the coldest month and annual precipitation,suggesting these factors may be primary determinants of plant diversity distribution.We also found that a threshold value of the normalized ShannoneWiener index(NH=0.4)approximately aligns with the contour line specifying 400 mm annual precipitation,serving as a rudimentary indicator for assessing plant diversity in arid versus humid climates.This study suggests that pollen diversity indices have remarkable potential for quantitatively reconstructing paleoclimatic parameters.
文摘Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change.
基金supported by the National Natural Science Foundation of China(grant number 31901109)Guangdong Basic and Applied Basic Research Foundation(grant number 2021A1515110744).
文摘Understanding how and why assemblage dissimilarity changes along spatial gradient is a great challenge in ecology,because answers to these questions depend on the analytical types,dimensions,and components of beta diversity we concerned.To obtain a comprehensive understanding of assemblage dissimilarity and its implications for biodiversity conservation in the Himalayas,we explored the elevational patterns and determinants of beta diversity and its turnover and nestedness components of pairwise and multiple types and taxonomic and phylogenetic dimensions simultaneously.Patterns of beta diversity and their components of different types and dimensions were calculated based on 96 sampling quadrats along an 1800-5400 m elevational gradient.We examined whether and how these patterns differed from random expectations using null models.Furthermore,we used random forest methods to quantify the role of environmental variables representing climate,topography,and human disturbance in determining these patterns.We found that beta diversity and its turnover component,regardless of its types and dimensions,shown a hump-shaped elevational patterns.Both pairwise and multiple phylogenetic beta diversity were remarkably lower than their taxonomic counterpart.These patterns were significantly less than random expectation and were mostly associated with climate variables.In summary,our results suggested that assemblage dissimilarity of seed plants was mostly originate from the replacement of closely related species determined by climate-driven environmental filtering.Accordingly,conservation efforts should better cover elevations with different climate types to maximalize biodiversity conservation,rather than only focus on elevations with highest species richness.Our study demonstrated that comparisons of beta diversity of different types,dimensions,and components could be conductive to consensus on the origin and mechanism of assemblage dissimilarity.
文摘Collaborative forest management (CFM) is a form of forest governance in which local communities are involved in the management and decision-making processes related to forest resources. It is believed that forests under such management are better in tree diversity and conservation status and thus hold more carbon stocks. The study assessed the impact of CFM on carbon stocks, tree species diversity & tree species density in Mabira Central Forest Reserve. Data were collected from plots that were systematically laid in the different purposively selected forest areas. The study findings show that there is no difference in stem density and carbon stocks between CFM and non-CFM areas. CFM areas had lower species richness compared to non-CFM areas. CFM areas, however, exhibited more species diversity than non-CFM areas. Climax colonization may favor a few dominant species over others, hence lowering species diversity despite the number of species being many in the understory, hence at the same time increasing species richness. Likewise, disturbance in CFM area may affect natural colonization and favor the emergency of many species either naturally or through assisted regeneration by reforestation, hence increasing diversity, whereas artificial selection of preferred species through harvesting may lower species richness, as observed. Recommendations for improving collaborative forest management (CFM) areas include implementing targeted interventions to enhance carbon sequestration, such as promoting reforestation and afforestation with high-carbon-storing species and strengthening monitoring and evaluation frameworks to assess carbon stock changes over time. Additionally, efforts should focus on enhancing biodiversity conservation by implementing more stringent protection measures and reducing human disturbance while encouraging community participation in biodiversity monitoring and conservation education.
基金Supported by the Natural Science Foundation of Fujian Province(No.2022J05278)the Marine and Fishery Development Special Fund of Xiamen(No.23YYST064QCB36)。
文摘Coastal ecosystems are plagued by high levels of microplastic pollution.Conducting baseline surveys is crucial to comprehend the distribution and influencing factors of this pollution.The present study investigates the spatiotemporal variation and diversity of microplastic on the coastal beaches in Xiamen City,China,considering the combined effects of seasons,human activities,and physicochemical properties of sediments.It is detected that the abundance of microplastics in Xiamen beaches was 0.271±0.01 items/g.The abundance of microplastics in dry season was significantly higher than in rainy season.In terms of spatial variation,the beaches that attracted a larger number of tourists exhibited significantly higher microplastic abundance.The temporal pattern of microplastic distribution on different beaches varied greatly due to region-specific human activities(e.g.,mangrove restoration project)and sedimentary properties(e.g.,bulk density).When the assemblage of microplastics in the coastal area was viewed as a biological community,the Shannon-Wiener index and Pielou's index were higher in rainy season and in the beaches with high intensity of tourist activities,which suggests that the human activities and the surface runoff may contribute to the diversity of microplastics on coastal beaches.Future investigations are encouraged to combine controlled experiments and long-term monitoring at multiple scales to elucidate the underlying mechanisms and factors associated with microplastic pollution in coastal zone.
基金Supported by National Natural Science Foundation of China(31900271,32160086)Key Technology Research for Identification of Toxic Fungi in Guizhou Province(GKHZC[2020]1Y065)+1 种基金Guizhou Grassroots Science Popularization Action Plan Project([2025]04)Study on Carbon Storage and Carbon Sink Value of Forest Vegetation in State-owned Shatang Forest Farms in Guangxi(2021KY02).
文摘[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were investigated for the first time to analyze the species diversity characteristics of wood-decaying fungi in this area. This analysis was conducted through a comprehensive 5-year field investigation and systematic identification process. [Results] The wood-decaying fungi exhibited a distinctive species composition and distribution pattern within karst habitats, encompassing significant groups such as Polyporaceae and Hymenochaetaceae. Furthermore, these fungi demonstrated varying functional characteristics across the two ecological types of standing tree decay and wood decay. It was observed that wood-decaying fungi had a significant impact on the material cycle within karst ecosystems by degrading lignin and cellulose. Furthermore, the distribution of species diversity was closely associated with the characteristics of karst geomorphology and the types of vegetation. [Conclusions] This study not only addresses the lack of background data regarding wood-decaying fungi resources in karst regions, but also elucidates the maintenance mechanisms of fragile ecosystems from the perspective of decomposers. It provides a scientific foundation for biodiversity conservation, the prevention and control of forest diseases, and sustainable ecological management in karst regions.
基金supported by the Southwest Minzu University Research Startup Funds (No.16011221038,RQD2022021)Double World-Class Project (No.CX2023010)。
文摘Wetland degradation is an escalating global challenge with profound impacts on animal diversity,particularly during successional processes.Birds,as highly mobile and environmentally sensitive organisms,serve as effective indicators of ecological change.While previous studies have primarily focused on local community structures and species diversity during a specific season,there is a need to extend the research timeframe and explore broader spatial variations.Additionally,expanding from simple species diversity indices to more multidimensional diversity indices would provide a more comprehensive understanding of wetland health and resilience.To address these gaps,we investigated the effects of wetland degradation on bird diversity across taxonomic,phylogenetic,and functional dimensions in the Zoige Wetland,a plateau meadow wetland biodiversity hotspot.Surveys were conducted during both breeding(summer)and overwintering(winter)seasons across 20 transects in 5 sampling areas,representing 4 degradation levels(pristine,low,medium,and high).Our study recorded a total of 106 bird species from 32 families and 14 orders,revealing distinct seasonal patterns in bird community composition and diversity.Biodiversity indices were significantly higher in pristine and low-degraded wetlands,particularly benefiting waterfowl(Anseriformes,Ciconiiformes)and wading birds(Charadriiformes)in winter,when these areas provided superior food resources and habitat conditions.In contrast,medium and highly degraded wetlands supported increased numbers of terrestrial birds(Passeriformes)and raptors(Accipitriformes,Falconiformes).Seasonal differences in taxonomic,phylogenetic,and functional diversity indices highlighted the contrasting ecological roles of wetlands during breeding and overwintering periods.Furthermore,indicator species analysis revealed key species associated with specific degradation levels and seasons,providing valuable insights into wetland health.This study underscores the importance of spatiotemporal dynamics in understanding avian responses to wetland degradation.By linking seasonal patterns of bird diversity to habitat conditions,our findings contribute to conservation efforts and provide a framework for assessing wetland degradation and its ecological impacts.
基金Supported by the Regional Innovation Development Joint Fund Project of the National Natural Science Foundation of China(No.U20A2087)the Shiptime Sharing Project of National Natural Science Foundation of China(No.42249911)。
文摘Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed,using various methods including at-sea fisheries resource surveys,fishing port surveys,underwater survey techniques,and data from literature,books,and databases,from which 1059 fish species across 40 orders,166 families,and 503 genera were identified.Among them,Acanthuriformes displayed the highest diversity,followed by Carangiformes and Perciformes.Notably,eight alien species were found in the Beibu Gulf.The International Union for Conservation of Nature(IUCN)Red List assessment revealed 51threatened species,primarily cartilaginous fish.Taxonomic changes affected 88.70%of species due to classification adjustments,misidentifications,and junior synonymy.This study contributed new data of the gulf,including one additional order,six new families,34 new genera,and 81 new species,emphasizing the dynamic nature of marine ecosystems.Fish diversity in the gulf was relatively lower than the broader South China Sea,attributed to limited habitats and survey methods.Different survey methods,such as gill nets,trap nets,and underwater cameras,yielded varying results.Ocean currents may have transported deep-sea species into the Beibu Gulf,leading to accidental records.Research gaps exist in unexplored areas,warranting further investigation.Therefore,the Beibu Gulf hosts significant marine biodiversity,but taxonomic challenges and undiscovered species require new research and conservation efforts.
基金supported by Innovation Scientists and Technicians Troop Construction Projects of Henan Province(Grant No.212101510003)the Central Plains Scholar Workstation Project(Grant No.224400510002)+1 种基金the Youth Science Foundation of Henan Province(Grant No.202300410136)the Experimental Development Foundation of Henan University of Science and Technology(Grant No.SY2324004)。
文摘Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_(h)),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties.
基金National Key Research and Development Program of China(2022YFF1000103)Postdoctoral Fellowship Program of CPSF under Grant Number GZC20240620.
文摘Background Mobile element variants(MEVs)have a significant and complex impact on genomic diversity and phe-notypic traits.However,the quantity,distribution,and relationship with gene expression and complex traits of MEVs in the pig genome remain poorly understood.Results We constructed the most comprehensive porcine MEV library based on high-depth whole genome sequencing(WGS)data from 747 pigs across 59 breeds worldwide.This database identified a total of 147,993 poly-morphic MEVs,including 121,099 short interspersed nuclear elements(SINEs),26,053 long interspersed nuclear elements(LINEs),802 long terminal repeats(LTRs),and 39 other transposons,among which 54%are newly discovered.We found that MEVs are unevenly distributed across the genome and are strongly influenced by negative selec-tion effects.Importantly,we identified 514,530,and 584 candidate MEVs associated with population differentiation,domestication,and breed formation,respectively.For example,a significantly differentiated MEV is located in the ATRX intron between Asian and European pigs,whereas ATRX is also differentially expressed between Asian and European pigs in muscle tissue.In addition,we identified 4,169 expressed MEVs(eMEVs)significantly associated with gene expression and 6,914 splicing MEVs(sMEVs)associated with gene splicing based on RNA-seq data from 266 porcine liver tissues.These eMEVs and sMEVs explain 6.24%and 9.47%,respectively,of the observed cis-heritability and high-light the important role of MEVs in the regulation of gene expression.Finally,we provide a high-quality SNP–MEV reference haplotype panel to impute MEV genotypes from genome-wide SNPs.Notably,we identified a candidate MEV significantly associated with total teat number,demonstrating the functionality of this reference panel.Conclusions The present investigation demonstrated the importance of MEVs in pigs in terms of population diversity,gene expression and phenotypic traits,which may provide useful resources and theoretical support for pig genetics and breeding.
基金funded by the Strategic Priority Research Program of Chinese Academy of Sciences (XDB31000000)the Joint Fund of the National Natural Science Foundation of China-Yunnan Province (U1902203)+1 种基金Major Program for Basic Research Project of Yunnan Province (202101BC070002)Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences (151C53KYSB20200019)
文摘Patterns and drivers of species–genetic diversity correlations(SGDCs)have been broadly examined across taxa and ecosystems and greatly deepen our understanding of how biodiversity is maintained.However,few studies have examined the role of canopy structural heterogeneity,which is a defining feature of forests,in shaping SGDCs.Here,we determine what factors contribute toα-andβ-species–genetic diversity correlations(i.e.,α-andβ-SGDCs)in a Chinese subtropical forest.For this purpose,we used neutral molecular markers to assess genetic variation in almost all adult individuals of the dominant tree species,Lithocarpus xylocarpus,across plots in the Ailaoshan National Natural Reserve.We also quantified microhabitat variation by quantifying canopy structure heterogeneity with airborne laser scanning on 201-ha subtropical forest plots.We found that speciesα-diversity was negatively correlated with geneticα-diversity.Canopy structural heterogeneity was positively correlated with speciesα-diversity but negatively correlated with geneticα-diversity.These contrasting effects contributed to the formation of a negativeα-SGDC.Further,we found that canopy structural heterogeneity increases speciesα-diversity and decreases geneticα-diversity by reducing the population size of target species.Speciesβ-diversity,in contrast,was positively correlated with geneticβ-diversity.Differences in canopy structural heterogeneity between plots had non-linear parallel effects on the two levels ofβ-diversity,while geographic distance had a relatively weak effect onβ-SGDC.Our study indicates that canopy structural heterogeneity simultaneously affects plot-level community species diversity and population genetic diversity,and species and genetic turnover across plots,thus drivingα-andβ-SGDCs.
基金supported by the National Natural Science Foundation of China(42271317)the Innovation Research Team Project of the Natural Science Foundation of Hainan Province(422CXTD515)。
文摘Latitudinal patterns of treeβ-diversity reveal important insights into the biogeographical processes that influence forest ecosystems.Although previous studies have extensively documentedβ-diversity within relatively small spatial extents,the potential drivers ofβ-diversity along latitudinal gradients are still not well understood at larger spatial extents.In this study,we determined whether treeβ-diversity is correlated with latitude in forests of southeastern China,and if so,what ecological processes contribute to these patterns of treeβ-diversity.We specifically aimed to disentangle the relative contributions from interspecific aggregation and environmental filtering across various spatial extents.We delineated regional communities comprising multiple nearby national forest inventory(NFI)plots around random focal plots.The number of NFI plots in a regional community served as a surrogate for spatial extent.We also used a null model to simulate randomly assembled communities and quantify the deviation(β-deviation)between observed and expectedβ-diversity.We found thatβ-diversity decreased along a latitudinal gradient and that this pattern was clearer at larger spatial extents.In addition,latitudinal patterns ofβ-deviation were explained by the degree of species spatial aggregation.We also identified environmental factors that driveβ-deviation in these forests,including precipitation,seasonality,and temperature variation.At larger spatial extents,these environmental variables explained up to 84%of theβ-deviation.Our results reinforce that ecological processes are scale-dependent and collectively contribute to theβ-gradient in subtropical forests.We recommend that conservation efforts maintain diverse forests and heterogeneous environments at multiple spatial extents to mitigate the adverse effects of climate change.
基金The research received approval from Children’s Hospital of Shanxi Committee (Approval Number:KLT6230511).
文摘BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both mother and baby.AIM To investigate the relationships between FI and pregnancy outcomes,particularly GDM and PIH,while also examining the mediating role of the dietary diversity score(DDS).METHODS A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant women.Participants were women aged 18 years or older who provided complete data on FI and pregnancy outcomes.The FI was measured via the Household Food Security Survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/L.The DDS is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between FI and PIH,and GDM.RESULTS Seventeen percent of participants reported experiencing FI during pregnancy.The study found a significant association between FI and an elevated risk of GDM[odds ratio(OR)=3.32,95%CI:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PIH(OR=0.10,95%CI:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth weight.The FI wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBS),low-density lipoprotein cholesterol,and triglyceride levels.Our results indicate that the DDS acts as a significant mediator in the relationship between FI and the incidence of GDM.In particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDS(P=0.002).CONCLUSION These findings underscore the serious challenges that FI presents during pregnancy and its effects on maternal and infant health.Additionally,the study explored how DDS mediates the relationship between FI and the incidence of GDM.
文摘This study explores the impact of board diversity on firm performance,with a focus on companies listed on the Singapore Stock Exchange(SGX).Board diversity is examined across various dimensions,including gender,age,ethnicity,and professional background,to understand its relationship with key performance indicators such as Return on Assets(ROA)and Return on Equity(ROE).Using a quantitative research approach,the study analyzes data from 90 publicly listed firms,employing descriptive statistics,correlation analysis,and multiple regression techniques.The findings reveal that the direct correlation between board diversity and financial performance,particularly in terms of ROA and ROE,is not statistically significant in the studied sample.Despite the lack of direct significance,the research underscores the nuanced and multifaceted role of diversity in corporate governance,suggesting that its impact may be more complex and influenced by various contextual factors.The study concludes by recommending that companies continue to enhance gender diversity,balance age structures,tailor professional backgrounds to industry needs,and manage board tenure effectively to optimize corporate governance and support sustainable growth.
