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Genetic diversity and population genetic structure of Paeonia suffruticosa by chloroplast DNA simple sequence repeats(cpSSRs) 被引量:2
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作者 Qi Guo Xian Xue +5 位作者 Duoduo Wang Lixia Zhang Wei Liu Erqiang Wang Xiaoqiang Cui Xiaogai Hou 《Horticultural Plant Journal》 2025年第1期367-376,共10页
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
关键词 Paeonia suffruticosa Chloroplast microsatellites(cp SSR) Genetic diversity Haplotypes Germplasm resources
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Does wetland degradation impact bird diversity differently across seasons?A case study of Zoige Alpine Wetland ecosystem 被引量:1
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作者 Chen Yang Siheng Chen Tianpei Guan 《Avian Research》 2025年第1期21-29,共9页
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
关键词 Bird diversity Community similarity Degraded wetland Indicator species Season effect
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Checklist of marine fishes in the Beibu Gulf:fish classification,resource protection,and biodiversity challenge 被引量:1
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作者 Zhisen LUO Murong YI +9 位作者 Xiaodong YANG Xiao CHEN Jinxi WANG Changping JIANG Fengming LIU Konglan LUO Xiongbo HE Hung-Du LIN Bin KANG Yunrong YAN 《Journal of Oceanology and Limnology》 2025年第1期232-247,共16页
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
关键词 northwestern South China Sea new record taxonomic change fish diversity survey method
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Diversity,Complexity,and Challenges of Viral Infectious Disease Data in the Big Data Era:A Comprehensive Review 被引量:1
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作者 Yun Ma Lu-Yao Qin +1 位作者 Xiao Ding Ai-Ping Wu 《Chinese Medical Sciences Journal》 2025年第1期29-44,I0005,共17页
Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning fr... Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning from the molecular mechanisms within cells to large-scale epidemiological patterns,has surpassed the capabilities of traditional analytical methods.In the era of artificial intelligence(AI)and big data,there is an urgent necessity for the optimization of these analytical methods to more effectively handle and utilize the information.Despite the rapid accumulation of data associated with viral infections,the lack of a comprehensive framework for integrating,selecting,and analyzing these datasets has left numerous researchers uncertain about which data to select,how to access it,and how to utilize it most effectively in their research.This review endeavors to fill these gaps by exploring the multifaceted nature of viral infectious diseases and summarizing relevant data across multiple levels,from the molecular details of pathogens to broad epidemiological trends.The scope extends from the micro-scale to the macro-scale,encompassing pathogens,hosts,and vectors.In addition to data summarization,this review thoroughly investigates various dataset sources.It also traces the historical evolution of data collection in the field of viral infectious diseases,highlighting the progress achieved over time.Simultaneously,it evaluates the current limitations that impede data utilization.Furthermore,we propose strategies to surmount these challenges,focusing on the development and application of advanced computational techniques,AI-driven models,and enhanced data integration practices.By providing a comprehensive synthesis of existing knowledge,this review is designed to guide future research and contribute to more informed approaches in the surveillance,prevention,and control of viral infectious diseases,particularly within the context of the expanding big-data landscape. 展开更多
关键词 viral infectious diseases big data data diversity and complexity data standardization artificial intelligence data analysis
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Differentiation of genetic diversity and byssal phenotype among wild populations of Mytilus coruscus located at different latitudes
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作者 LIN Yuetong WANG Yuqing +2 位作者 NI Jiyue LI Yifeng LU Xia 《水产学报》 北大核心 2025年第8期109-120,共12页
The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yi... The mussel is one of the main cultivated species in the world.A significant challenge faced by suspension-cultured mussels is the high incidence of mussel fall-off from cultivation ropes,adversely impacting harvest yields,which have been documented at commercial mussel farms in the United Kingdom,the United States of America,Canada,Spain,New Zealand and China.Byssus is an important attachment structure for marine mussels,and weakness in byssal thread attachment is a major factor leading to mussel detachment from ropes.To investigate the relationship between genetic variability and byssal thread phenotypic characteristics in the hard-shelled mussel(Mytilus coruscus),we collected three wild populations of M.coruscus from different latitudes in the East China Sea,including the Shengsi(SS),Jiaojiang(JJ),and Fuding(FD)populations.The genetic diversity and structure of these populations were investigated using 10 microsatellite loci.The mean observed heterozygosity(Ho)in the SS population was 0.44,higher than the mean Ho values of the JJ(0.40)and FD(0.39)populations.The mean inbreeding coefficients(F_(is))in the SS population was 0.20,lower than the mean F_(is)values of the JJ(0.33)and FD populations(0.40).These results revealed that the SS population exhibited higher genetic diversity compared to the other two populations.The different numbers of private alleles(P_(a))in the three populations,ranging from 10 to 17,suggest that these populations have experienced selective pressures from various environments.Moreover,genetic differentiation was observed in the genetic distance between the SS population and the other two populations.We also examined the phenotypic characteristics of their byssal threads.There were significant differences in byssus attachment strength among the three populations,with the SS population located at the highest latitude secreting more byssal threads and exhibiting greater byssal breaking force and plaque adhesion strength,while the Fuding(FD)population located at the lowest latitude had the weakest byssal attachment.The observed differentiation in private alleles and byssus phenotypes might suggest that the three wild populations have experienced different environmental selective pressures.This study provides insight for future genetic enhancement programs aimed at improving byssus attachment in M.coruscus. 展开更多
关键词 Mytilus coruscus MICROSATELLITE genetic diversity genetic structure byssal phenotype
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Diversity and Morphometrics of Palm Weevils of the Genus Rhynchophorus in Maniema Province, Democratic Republic of Congo
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作者 Angundji Yumbi Chérif Muhigwa Bahananga Jean-Berckmans +2 位作者 Manga Tshomba Joseph Dieudonné Cikwanine Murhabale Cisirika Bertin 《Advances in Entomology》 2025年第1期152-173,共22页
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
关键词 INVENTORY diversity MORPHOMETRICS Palm Weevils
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Assessment of Floristic Diversity at Two Protected Sites on the Outskirts of Sena Oura National Park, Chad
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作者 Robert Tchingonta Maxime Banoin +1 位作者 Koussou Mian-Oudanang Sougnabe Pabame 《Agricultural Sciences》 2025年第1期178-192,共15页
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
关键词 Floristic diversity Protected Sites PERIPHERY Area Producty CHAD
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Woody Diversity in Cult Places (Cemeteries, Mosques, and Parishes) in Ziguinchor City (Senegal)
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作者 Aly Diallo Antoine Sambou +4 位作者 Landing Ndiaye Jean Bassene Thierno Sarr Serigne Saliou Mbacke Ngom Elhadji Nfally Yoro Diedhiou 《American Journal of Plant Sciences》 2025年第1期114-132,共19页
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
关键词 Tree diversity Biodiversity Conservation Cult Places
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Multifaceted plant diversity patterns across the Himalaya:Status and outlook
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作者 Mustaqeem Ahmad Ya-Huang Luo +10 位作者 Sonia Rathee Robert A.Spicer Jian Zhang Moses C.Wambulwa Guang-Fu Zhu Marc W.Cadotte Zeng-Yuan Wu Shujaul Mulk Khan Debabrata Maity De-Zhu Li Jie Liu 《Plant Diversity》 2025年第4期529-543,共15页
Mountains serve as exceptional natural laboratories for studying biodiversity due to their heterogeneous landforms and climatic zones.The Himalaya,a global biodiversity hotspot,hosts rich endemic flora,supports vital ... Mountains serve as exceptional natural laboratories for studying biodiversity due to their heterogeneous landforms and climatic zones.The Himalaya,a global biodiversity hotspot,hosts rich endemic flora,supports vital ecosystem functions,and offers a unique window into multifaceted plant diversity patterns.This review synthesizes research on Himalayan plant diversity,including species,phylogenetic,functional,and genetic dimensions,highlighting knowledge gaps and solutions.Research on Himalayan plant diversity has developed significantly.However,gaps remain,especially in studies on phylogenetic and functional diversity.The region's vegetation ranges from tropical rainforests to alpine ecosystems,with species richness typically following a hump-shaped distribution along elevation gradients.The eastern Himalaya exhibits higher plant diversity than the central and western regions.Low-elevation communities were found to be more functionally diverse,whereas high-elevation communities displayed greater ecological specialization.Communities at mid-elevations tend to show greater phylogenetic diversity than those at higher and lower elevations.The eastern and western flanks of the Himalaya retain high levels of genetic diversity and serve as glacial refugia,whereas the central region acts as a hybrid zone for closely related species.Himalayan plant diversity is shaped by historical,climatic,ecological and anthropogenic factors across space and time.However,this rich biodiversity is increasingly threatened by environmental change and growing anthropogenic pressures.Unfortunately,research efforts are constrained by spatial biases and the lack of transnational initiatives and collaborative studies,which could significantly benefit from interdisciplinary approaches,and other coordinated actions.These efforts are vital to safeguarding the Himalayan natural heritage. 展开更多
关键词 Biodiversity hotspot Elevational gradients Functional diversity Genetic diversity HIMALAYA Phylogenetic diversity
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Effective palynological diversity indices for reconstructing angiosperm diversity in China
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作者 Yuxuan Jiang Fuli Wu +3 位作者 Xiaomin Fang Haitao Wang Yulong Xie Cuirong Yu 《Plant Diversity》 2025年第2期244-254,共11页
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 p... 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, Berger-Parker index, Simpson diversity index, Hill index, and Shannon-Wiener 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 Shannon-Wiener index. Our analyses indicated that the most effective indices at reflecting plant diversity are the Shannon-Wiener index and Berger-Parker index. Numerical analysis revealed that palynological diversity(measured using the Shannon-Wiener 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 Shannon-Wiener 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
关键词 Angiosperm diversity POLLEN diversity indices Climatic parameters
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Assessing the contributions of site and species to plant beta diversity in alpine grassland ecosystems
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作者 Jie Li Xiao Pan Pang Zheng Gang Guo 《Plant Diversity》 2025年第4期633-642,共10页
Understanding plant diversity within geographical ranges and identifying key species that drive community variation can provide crucial insights for the management of grasslands.However,the contribution of both local ... Understanding plant diversity within geographical ranges and identifying key species that drive community variation can provide crucial insights for the management of grasslands.However,the contribution of both local sites and plant species to beta diversity in grassland ecosystems has yet to be accurately assessed.This study applied the ecological uniqueness approach to examine both local contributions to beta diversity(LCBD)and species contributions to beta diversity(SCBD)across six major geographical ranges in alpine grasslands.We found that LCBD was driven by species turnover,with climate,plant communities,and their interactions influencing LCBD across spatial scales.LCBD values were high in areas with low evapotranspiration,high rainfall variability,and low species and functional richness.Precipitation seasonality predicted large-scale LCBD dynamics,while plant community abundance explained local LCBD variation.In addition,we found that SCBD were confined to species with moderate occupancy,although these species contributed less to plant biological traits.Our findings are crucial for understanding how ecological characteristics influence plant beta diversity in grasslands and how it responds to environmental and community factors.In addition,these findings have successfully identified key sites and priority plants for conservation,indicating that using standardized quadrats can support the assessment of the ecological uniqueness in grassland ecosystems.We hope these insights will inform the development of conservation strategies,thereby supporting regional plant diversity and resisting vegetation homogenization. 展开更多
关键词 Ecological uniqueness Beta diversity TURNOVER Functional diversity Grassland management
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Avian phylogenetic and functional diversity and their influencing factors in urban parks of Nanjing,China
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作者 Qihuan He Xu Jiang +5 位作者 Yinuo Feng Jie Shao Xingchang Yang Xueru Yang Xinwei Tan Yanping Wang 《Avian Research》 2025年第4期600-609,共10页
The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic ... The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system. 展开更多
关键词 BIRDS Community construction Functional diversity Phylogenetic diversity URBANIZATION Urban parks
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Topographic complexity drives trait composition as well as functional and phylogenetic diversity of understory plant communities in microrefugia:New insights for conservation
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作者 Kata Frei Anna E-Vojtkó +6 位作者 Csaba Tölgyesi Andráas Vojtkó Tünde Farkas Lászlo Erdös Gáabor Li Ádáam Lörincz Zoltáan Báatori 《Forest Ecosystems》 2025年第2期209-219,共11页
Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental condit... Topographic complexity supports the maintenance of a high diversity of microhabitats,which may act as important‘safe havens’-or microrefugia-for biodiversity.Microrefugia are sites with specific environmental conditions that facilitate the persistence of species during environmental changes and exhibit unique ecoevolutionary dynamics.However,our knowledge about how topographic complexity and related ecoevolutionary selective forces influence the functional and phylogenetic signatures of species assemblages in microrefugia is very limited.Although the conceptual framework on the systematic integration of plant functional traits into the study of refugia is well established,more empirical studies on functional trait composition and functional diversity in refugia are urgently needed for more effective conservation.Here we analyzed the distribution of various plant functional traits and phylogenetic patterns in microhabitats(south-and north-facing slopes,and bottoms)of 30 large topographic depressions(i.e.doline microrefugia)and microhabitats of the surrounding plateaus in two distant forested karst regions.We found that plant assemblages in the understory of dolines and their surroundings are characterized by unique functional values and combinations of traits.Doline bottoms had the highest functional diversity among doline microhabitats and supported plant assemblages with considerably different trait compositions from the plateaus.Bottoms also had the highest phylogenetic diversity.These results suggest that topographic complexity in forested dolines has a significant effect on the distribution of plant functional traits in the understory.High functional and phylogenetic diversity in doline bottoms can have important consequences for the long-term survival of plant populations,highlighting that these microhabitats may provide a higher resilience and support an adaptive community-level response to natural and anthropogenic stressors.Understanding mechanisms that drive the survival of species within microrefugia is required to determine the best conservation and management strategies. 展开更多
关键词 DOLINE Forest herbs Functional diversity MICROCLIMATE MICROHABITAT Phylogenetic diversity Species trait Vegetation
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Altitudinal patterns of plant diversity, cover, and life forms in a warm arid mountain: Insights from Sierra de Velasco, Argentina
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作者 Sofia V.LIZARRAGA Omar VARELA Julieta CARILLA 《Journal of Mountain Science》 2025年第3期873-887,共15页
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
关键词 Elevation gradient Plant diversity Life forms Arid mountains diversity pattern Climatic drivers
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Yak and Tibetan sheep mixed grazing enhances plant functional diversity in alpine grassland
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作者 Yuzhen Liu Xinquan Zhao +4 位作者 Xiaoxia Yang Wenting Liu Bin Feng Shengnan Sun Quanmin Dong 《Journal of Integrative Agriculture》 2025年第3期936-948,共13页
The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,resear... The response of plant functional diversity to external disturbances not only effectively predicts changes in the ecosystem but it also reflects how plant communities use external environmental resources.However,research on how different herbivore assemblages affect plant functional diversity is limited.Therefore,this study systematically explored the effects of three typical herbivore assemblages(yak grazing,Tibetan sheep grazing,and mixed grazing by yaks and Tibetan sheep)on species richness,plant functional diversity,and soil physicochemical properties in alpine grasslands on the Qinghai-Tibet Plateau,China.This study further investigated the primary mechanisms driving the changes in plant functional diversity.The results indicate four key aspects of this system:(1)Grazing significantly enhanced plant functional diversity,particularly when the mixed grazing by yaks and Tibetan sheep was applied at a ratio of 1:2.This ratio showed the most substantial improvement in the functional dispersion index and Rao's quadratic entropy index.(2)Compared to enclosed treatments,grazing increased species richness andβ-diversity,contributing to higher plant functional diversity.(3)Grazing treatments affected various plant traits,such as reducing plant community height and leaf thickness while increasing specific leaf area.However,the impact on plant functional diversity was most pronounced under the mixed grazing by yaks and Tibetan sheep at a ratio of 1:2.(4)Speciesα-diversity was positively correlated with plant functional diversity.Changes in plant functional diversity were primarily regulated by variations in soil physicochemical properties.Specifically,increases in soil available nitrogen significantly promoted changes in plant functional diversity,while increases in soil available potassium and bulk density had a significant inhibitory effect on these changes.Long-term grazing significantly reduced the height of plant communities in alpine meadows,while a balanced mixture of yak and Tibetan sheep grazing,especially at a ratio of 1:2,enhanced plant functional diversity the most.This suggests that,under these conditions,the use of external environmental resources by the plant community is optimized. 展开更多
关键词 alpine grassland adaptive management herbivore assemblages species diversity functional diversity
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Climate-driven environmental filtering determines hump-shaped elevational pattern of seed plant beta diversity in the central Himalayas
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作者 Jianchao Liang Zhifeng Ding +3 位作者 Ganwen Lie Zhixin Zhou Zhixiang Zhang Huijian Hu 《Plant Diversity》 2025年第2期264-272,共9页
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
关键词 Beta diversity Phylogenetic diversity Assembly process Elevational gradient Environmental filtering HIMALAYAS
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Biogeographic affinitypartly shapes woody plant diversity along an elevational gradient in subtropical forests
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作者 Zhaochen Zhang Fang Wang +13 位作者 Xiaoran Wang Mufan Sun Pu Zheng Jingchao Zhao Junhong Chen Min Guan Pengcheng Liu Xiaofan Shang Yaoshun Lu Qingpei Yang Qingni Song Lin Chen Quying Zhong Jian Zhang 《Plant Diversity》 2025年第5期784-792,共9页
The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents... The ecological and evolutionary mechanisms underlying montane biodiversity patterns remain unresolved.To understand which factors determined community assembly rules in mountains,biogeographic affinity that represents the biogeographic and evolutionary history of species should incorporate with current environments.We aim to address two following questions:1)How does plant taxonomic and phylogenetic diversity with disparate biogeographic affinitiesvary along the subtropical elevational gradient?2)How do biogeographic affinityand environmental drivers regulate the community assembly?We collected woody plant survey data of 32 forest plots in a subtropical mountain of Mt.Guanshan with typical transitional characteristics,including 250 woody plant species belonging to 56 families and 118 genera.We estimated the effects of biogeographic affinity,climate and soil properties on taxonomic and phylogenetic diversity of plant communities employing linear regression and structural equation models.We found that the richness of temperate-affiliated species increased with elevations,but the evenness decreased,while tropical-affiliatedspecies had no significantpatterns.Winter temperature directly or indirectly via biogeographic affinityshaped the assemblage of woody plant communities along elevations.Biogeographic affinityaffected what kind of species could colonize higher elevations while local environment determined their fitnessto adapt.These results suggest that biogeographic affinityand local environment jointly lead to the dominance of temperate-affiliated species at higher elevations and shape the diversity of woody plant communities along elevational gradients.Our findingshighlight the legacy effect of biogeographic affinityon the composition and structure of subtropical montane forests. 展开更多
关键词 Taxonomic diversity Phylogenetic diversity Biogeographic affinity Cold tolerance Phylogenetic niche conservatism
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Diversity and dynamic response of anaerobic ammonia oxidation granular sludge
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作者 Jiahong Ye Xiang Li +6 位作者 Yan Yuan Yayi Wang Yong Huang JunMa Han Wang Pengze Dang Pei-ling Xu 《Journal of Environmental Sciences》 2025年第6期262-275,共14页
Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, An... Red anaerobic ammonia oxidation (Anammox) granular sludge (AnGS) has been reported insuccessfully operating Anammox systems, and its color is associated with sludge activity.However, in long-term operating systems, AnGS exhibits different sensory colors, physicalstructures, community structures, and denitrification performance, but the relationship betweenthem has not yet been elucidated.The AnGS of the Anammox system, which has beenin operation for more than a decade, can be divided into twomain categories: red and white.The specific Anammox activity (SAA) in conventional red AnGS increased continuously asthe particle size increased from <0.51 mm to 6.02 ± 0.84 mm. The SAA of white AnGS wereslightly lower than those of red AnGS with similarly-size granules but significantly higherthan AnGS with smaller red granules. Compared with red AnGS, the extracellular polymericsubstances of white AnGS were significantly reduced,mainly due to the higher intracellulariron content, resulting in lower heme c concentration. Thus, heme c may prove not to bean evaluative tool for measuring Anammox activity. Red and white AnGS, whether throughself-aggregation or adsorption by hydroxyl apatite and other carriers, will face the fate ofinternal voids during particle size growth. White AnGS exhibited amore complex microbialcommunity than red AnGS. Candidatus Brocadia was abundant in red AnGS and the abundanceincreased with increasing granule size. Candidatus Kuenenia and Candidatus Jetteniamade significant contributions to denitrification in white AnGS. This study provides a newperspective on particle selection for anammox engineering applications. 展开更多
关键词 Anaerobic ammonium oxidation granular sludge Sensory diversity Intracellular iron HEME Enzyme activity Microbial diversity
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Patterns of genetic diversity in five species of Passeriformes co-distributed in an environmental gradient
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作者 Marcela Restrepo-Arias Héctor F.Rivera-Gutiérrez +2 位作者 Iván Darío Soto-Calderón Ernesto Pérez-Collazos Catalina González-Quevedo 《Avian Research》 2025年第3期519-530,共12页
Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental grad... Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation. 展开更多
关键词 Adaptive genetic diversity Microsatellites Neutral genetic diversity Restricted distribution Tol-ike receptor Wide distribution
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