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Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities
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作者 Jian-Chao Liang Zhi-Feng Ding +7 位作者 Chun-Lin Li Yi-Ming Hu Zhi-Xin Zhou Gan-Wen Lie Xiao-Nan Niu Wen-Bin Huang Hui-Jian Hu Xing-Feng Si 《Zoological Research》 SCIE CSCD 2024年第1期125-135,共11页
Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity studies.Here,we examined whethe... Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity studies.Here,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in China vary across(1)regions on both sides of the Hu Line,which demarcates China’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal ability.TBD and PBD were calculated and partitioned into turnover and nestedness components using a moving window approach.Variables representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental filtering.Spatial distance was considered to assess the impact of dispersal limitation.Variance partitioning analysis was applied to assess the relative roles of these variables.In general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental filtering.However,different dominant environmental filters on either side of the Hu Line led to divergent beta diversity patterns.Specifically,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,respectively.Additionally,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous assemblages.Our results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological factors.Identifying a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete conclusions.Consequently,a comprehensive understanding of large-scale beta diversity patterns and effective planning of conservation strategies necessitate the consideration of both geographical background and species dispersal ability. 展开更多
关键词 Beta diversity Environmental filtering Dispersal limitation Hu Line Species dispersal ability Breeding birds
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Comparing community birdwatching and professional bird monitoring with implications for avian diversity research: a case study of Suzhou, China 被引量:7
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作者 Yan Zhou Anping Chen +9 位作者 Jenny QOuyang Yanlin Liu Aiyu Zheng Zaixi Yang Yong Zhang Bin Wang Yifei Jia Shengwu Jiao Qing Zeng Changhu Lu 《Avian Research》 CSCD 2020年第2期122-132,共11页
Background:In the past decades,birdwatching as a hobby developed rapidly and produced ample scientific records that have aided conservation efforts.Therefore,it is increasingly attractive to promote avian research by ... Background:In the past decades,birdwatching as a hobby developed rapidly and produced ample scientific records that have aided conservation efforts.Therefore,it is increasingly attractive to promote avian research by providing data from birdwatching.Methods:We compared records from 16 years of community birdwatching and a 1-year formalized bird monitoring in Suzhou,China to study the similarities and differences between the two monitoring methods.Results:We showed that within the 325 bird species recorded by the two methods,an annual average of 108 species were documented by community science and 223 bird species were recorded by 1-year formalized monitoring.Measured by the number of bird species recorded per survey trip,the bird monitoring activity of community birdwatchers was significantly lower.Furthermore,the monitoring intensity of community birdwatching measured as the average survey trips per site each survey year was also lower than that of formalized bird monitoring.In addition,community birdwatchers preferred urban landscapes to rural areas.Conclusions:Community birdwatching could record the majority of local birds and complements the professional surveys in avian research.Well designed and coordinated community science can be used to expand the knowledge about avian distribution and population dynamics.These findings are critical for the development of conservation science with regard to community involvement. 展开更多
关键词 avian diversity Birdwatching Community science CONSERVATION Formalized bird monitoring
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Avian and Habitat Diversity in the Semi-Arid Lands of Baringo South, Kenya 被引量:1
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作者 George Morara Ogendi Rhoda N. Ondieki 《Open Journal of Ecology》 2020年第8期518-536,共19页
Semi-arid wooded-shrublands are important and critical habitats that provide breeding and feeding grounds for a variety of bird species, some of which are endangered, vulnerable or threatened with extinction. Habitat ... Semi-arid wooded-shrublands are important and critical habitats that provide breeding and feeding grounds for a variety of bird species, some of which are endangered, vulnerable or threatened with extinction. Habitat type and size influence abundance and diversity of birds globally and particularly in developing countries that are characterized by rapid human population growth and haphazard urban, agricultural and industrial development. The objective of this study was to assess avian and habitat diversity at Chemeron, a semi-arid land in the northern rangelands of Kenya. The study was guided by four questions: What kind of Habitat types are present at Chemeron study area? What kind of birds are found at Chemeron area? What is the conservation status of birds found at Chemeron area? What are the functional feeding guilds of birds that are found in the study area? How does the habitat type influence bird species abundance and diversity at Chemeron? Four 2-km long transects radiating from a central point within the study area were selected for a ground survey of birds that was conducted on foot. The surveys were conducted between 06:30 and 09:30 and 16:00 and 18:00 from October 2019 to April 2020. Bird species were observed and identified to the species level using high-resolution binoculars, field guidebooks and available taxonomic keys. Our surveys documented two main habitat types: <em>Acacia-Balanites-Boscia</em> woodlands dominated by <em>Acacia senegal</em>,<em> Acacia mellifera</em>, <em>Acacia nilotica</em>, <em>Boscia angustifolia</em>, and <em>Balanites aegyptica</em>. The second kind of habitat consisted of the invasive <em>Acalypha fruticosa</em> and <em>Indigofera arrecta</em> with <em>Acacia reficiens-Acacia brevispica</em> overstorey. A total of 53 bird species were sighted and identified the vulnerable Yellow necked spurfowl (<em>Francolinus leucoscepus</em>). Seventy-nine percent of the birds were sighted as singles or in pairs except for the gregarious white browed sparrow weaver (<em>Plocepasser mahali</em>), <em>Apus caffer</em>, <em>Numida meleagris</em>, <em>Streptopelia senegalensis</em>, <em>Dinemellia dinemelli</em> and <em>Corythaxoides leucogaster</em>. Significant differences in the various species diversity indices among the six transects were observed (p < 0.05). Approximately 60% of the birds belong to the insectivorous and omnivorous feeding guild. Charcoal burning and uncontrolled harvesting of wood are the major threats to the avian habitats in the study area. The high diversity of bird species in the study area can be attributed to the varied diversity of habitats that provide feeding, nesting, refuge and breeding grounds for the birds. From the foregoing findings, we can conclude that the ASALs of Baringo South offer ample habitat for a large number of bird species including the vulnerable Yellow necked spurfowl. The variations in various bird diversity indices can be attributed to the observed heterogeneity of habitats in the study area. We recommend wise use of rangeland resources and protection of critical avian habitats within the ASALs. Efforts should be geared towards livelihoods diversification and empowerment of the Lake Bogoria communities. This will reduce the pressure on the wooded shrublands that is widespread in the study area. 展开更多
关键词 HABITAT avian diversity Extinction Acacia Woodlands RANGELANDS
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Avian diversity in hedgerows,preference to hedgerow types and their conservation at Angacha (Kembatta),central Ethiopia
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作者 Abebe KOKISO 《Chinese Birds》 2012年第2期137-142,共6页
The present study aimed to investigate avian diversity in hedgerows at Angacha, in the Kembatta zone, Ethiopia. Transect and point-count methods were deployed to determine avian diversity, species richness, similarity... The present study aimed to investigate avian diversity in hedgerows at Angacha, in the Kembatta zone, Ethiopia. Transect and point-count methods were deployed to determine avian diversity, species richness, similarity and preferences across five sub study sites. Diversity and preferences of birds to hedgerow types varied in relation to their vegetation composition and structure. Five endemic species, i.e., Rüppel’s Black Chat (Cossyfa semirufa), the White-cheeked Turaco (Tauraco leucotis), the Banded Barbet (Lybius undatus), the Abyssinian Oriole (Oriolus monacha) and the Wattled Ibis (Bostrychia carucullatta) were recorded in the thick hedgerow type. Thickness, height and width of hedgerows affected the diversity, distribution and habitat preference of birds. Thick hedgerow types showed the highest avian species diversity, richness and similarity. There was a high correlation between the hedgerow diversity and its bird diversity, which was directly associated with habitat quality. Bird species diversity and preference for hedgerow types require important conservation and management priorities. 展开更多
关键词 avian diversity HEDGEROWS preference to hedgerow types species richness and similarity
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Control of highly pathogenic avian influenza through vaccination 被引量:1
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作者 Xianying Zeng Jianzhong Shi Hualan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1447-1453,共7页
The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian in... The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus. 展开更多
关键词 avian influenza CONTROL highly pathogenic VACCINATION
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Avian Abundance, Diversity and Conservation Status in Etago Sub-County Kisii County Kenya
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作者 Mokono M. Isaac Shadrack M. Muya +1 位作者 Winnie Kiiru Muchane Muchai 《Open Journal of Ecology》 2019年第5期157-170,共14页
Bird’s species diversity and abundance are being threatened due to agricultural activities and anthropogenic practices which causes habitat destruction and fragmentation. Understanding how avian species respond to ha... Bird’s species diversity and abundance are being threatened due to agricultural activities and anthropogenic practices which causes habitat destruction and fragmentation. Understanding how avian species respond to habitat destruction is important towards development of effective measures to ensure that the environment is protected. A study on avian abundance, diversity and conservation status was conducted in Etago Sub-County, Kisii County Kenya from September 2018 to February 2019. Point counts and time species counts were used to carry out birds’ survey to determine their abundance and diversity in the secondary forest, sugarcane plantations, human settlement and mixed firms. A total of 4992 individuals were observed and recorded in the entire study area. The human settlement had the highest density of 1.664 ± 0.18 birds/ha followed by sugarcane plantation with 1.092 ± 0.16 birds/ha and Nyangweta secondary forest was third with 0.0819 ± 0.13. Mixed firms had the least density of 0.95 ± 0.017 bird/ha. Further Dunn’s multiple comparisons test showed that Mixed farming and forest had no significant difference and had mean rank difference of 11.37. In mixed farming vs human settlement there was a significant difference with a mean rank difference of 57.38;in mixed farming vs sugarcane farms there was no significant difference;in the four habitats, 114 species of birds were cumulatively recorded. Out of these, 106 species were recorded in the secondary forests, 98 human settlement and 87 species in the sugarcane plantations and 55 in mixed farms. There was a significant difference in bird diversity in the four habitats where Secondary forest had the highest diversity of 3.85 and sugarcane plantations had a diversity of 3.71 while human settlement and mixed firms had lower diversities of 2.6 and 2.5 respectively (df1 = 2, df2 = 0.0 F = 0.00001, P = 0.00001). 展开更多
关键词 Density SIMILARITY diversity ABUNDANCE Richness
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Resilience effects for household food expenditure and dietary diversity in rural western China 被引量:1
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作者 Xiao Han Kaiyu Lyu +1 位作者 Fengying Nie Yuquan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期384-396,共13页
A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in weste... A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)model.Results show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to 2021.Households with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food choices.It can be because resilient households will allocate more money to food expenditure instead of saving for livelihood uncertainty.Thus,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management strategies.This,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality. 展开更多
关键词 RESILIENCE food expenditure dietary diversity China risk management
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Off-farm employment,agriculture production activities,and household dietary diversity in environmentally and economically vulnerable areas of Asia 被引量:1
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作者 Yunli Bai Xuanye Zeng +1 位作者 Chao Fu Linxiu Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期359-373,共15页
Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero Hunger.This study aims to investigate the role of off-fa... Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero Hunger.This study aims to investigate the role of off-farm employment in improving dietary diversity through substitution effect and complementary effect with agricultural production activities and income effect.This study adopts Poisson/Tobit/Probit/OLS regressions and the instrument variable method based on the primary survey data collected among 1,282 households at 12 sites in environmentally and economically vulnerable areas of China,Nepal,Cambodia,Thailand,and Myanmar in 2019.The results show that off-farm employment is positively associated with household dietary diversity and the consumption of flesh meat,fish and other aquatic animals,fruits,and milk and dairy products,which are rich in protein and micronutrients.The results of mechanism analysis show that off-farm employment contributes to household dietary diversity by improving crop diversity,especially for poor households,boosting the probability of livestock raising for households with the middle one-third disposal income,and increasing household income.The positive association between off-farm employment and household dietary diversity is much higher for households with the bottom one-third disposal income,low illiteracy,and from upper-middle income countries.These findings imply that off-farm employment does play a vital role in achieving multiple benefits of poverty alleviation,malnutrition reduction,and agrobiodiversity conservation in environmentally and economically vulnerable areas.However,it may enlarge the gaps in dietary diversity between households with low human capital and from low and lower-middle income countries and those with high human capital and from middle-high countries. 展开更多
关键词 off-farm employment dietary diversity income effect substitution effect complementary effect
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Masting effect on alpha and beta avian diversity in fragmented forests of relict?endangered Mexican Beech(Fagus grandifolia subsp.mexicana)
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作者 Ernesto CRodríguez-Ramírez Levinn Camacho-Islas +2 位作者 Ana Paola Martínez-Falcón Isolda Luna-Vega Pilar Carbó-Ramírez 《Avian Research》 SCIE CSCD 2021年第4期576-590,共15页
Background:Tropical montane cloud forests are one of the most important hotspots on Earth and show presence of relict-endemic and endangered species,representing about 14%of the total tropical forest worldwide.Synchro... Background:Tropical montane cloud forests are one of the most important hotspots on Earth and show presence of relict-endemic and endangered species,representing about 14%of the total tropical forest worldwide.Synchronous seed production or masting in tropical montane cloud tree species is a widespread reproductive strategy of decidu-ous and evergreen broad-leaved tree associations to decrease costs of reproduction and ensure offspring.Masting event maintains a high avian diversity,which can be modified by phenological process(seed production and non-seed production).Methods:The main aim of this study was to assess alpha and beta avian diversity and whether the composition of the trophic guild modifies among phenological processes and between two fragmented relict-endangered Mexican Beech(Fagus grandifolia subsp.mexicana)forests(Medio Monte and El Gosco)in the Mexican state of Hidalgo.In addi-tion,we evaluated beechnut production.Results:We recorded 36 bird species,11 of them included in some conservation risk status,and 5 endemic species.Alpha diversity values were dissimilar in avian richness(q=0)among phenological processes and between frag-mented beech forests.Avian communities among three phenological processes and between fragmented forests were structurally similar,dominated during immature seeds the Brown-backed Solitaire(granivores-insectivores-frugivores);during mature seeds the White-crowned Parrot(Pionus senilis,granivores-frugivores);and the Dwarf Jay(Cyanolyca nana,insectivores)was abundant during low seed quality.The complementarity index was high among phenological processes and low between forests.We found a high bird turnover value between immature seeds—mature seeds and during mature seeds—low seed quality.Furthermore,a similar pattern was recorded between the two study forests.Seed production showed a high number of undamaged beechnuts in Medio Monte,while in El Gosco beechnuts were attacked by insects.Conclusions:Our results reflect that masting phenological process and contrasting study forests'structure influence the shifts in alpha and beta diversity of seed and non-seed bird consumers.Our study reaffirms the importance of continuing studies throughout masting in all the Mexican Beech forests to address regional efforts in preserving the relict-ecological interactions. 展开更多
关键词 avian seed consumers Bird species Synchronous seed production Tropical montane cloud forest TURNOVER Zentrygon albifacies
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Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020 被引量:1
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作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
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
关键词 Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
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Biodiversity metrics on ecological networks: Demonstrated with animal gastrointestinal microbiomes 被引量:1
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作者 Zhanshan(Sam)Ma Lianwei Li 《Zoological Research(Diversity and Conservation)》 2024年第1期51-65,共15页
Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity... Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity should be similar with measuring national wealth.Indeed,there have been many parallels between ecology and economics,actually beyond analogies.For example,arguably the second most widely used biodiversity metric,Simpson(1949)’s diversity index,is a function of familiar Gini-index in economics.One of the biggest challenges has been the high“diversity”of diversity indexes due to their excessive“speciation”-there are so many indexes,similar to each country’s sovereign currency-leaving confused diversity practitioners in dilemma.In 1973,Hill introduced the concept of“numbers equivalent”,which is based on Renyi entropy and originated in economics,but possibly due to his abstruse interpretation of the concept,his message was not widely received by ecologists until nearly four decades later.What Hill suggested was similar to link the US dollar to gold at the rate of$35 per ounce under the Bretton Woods system.The Hill numbers now are considered most appropriate biodiversity metrics system,unifying Shannon,Simpson and other diversity indexes.Here,we approach to another paradigmatic shift-measuring biodiversity on ecological networks-demonstrated with animal gastrointestinal microbiomes representing four major invertebrate classes and all six vertebrate classes.The network diversity can reveal the diversity of species interactions,which is a necessary step for understanding the spatial and temporal structures and dynamics of biodiversity across environmental gradients. 展开更多
关键词 Biodiversity on network Hill numbers Animal gut microbiome Network link diversity Network species diversity Network abundance-weighted link diversity
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Biodiversity responses to insular fragmentation in Amazonia: Two decades of research in the Balbina Hydroelectric Reservoir 被引量:1
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作者 Ana Filipa Palmeirim Maíra Benchimol +4 位作者 Danielle Storck-Tonon Anderson S.Bueno Isabel L.Jones Gilmar Klein Carlos A.Peres 《Zoological Research(Diversity and Conservation)》 2024年第2期106-116,共11页
As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laborato... As hydropower development expands across lowland tropical forests,flooding and concomitant insular fragmentation have become important threats to biodiversity.Newly created insular landscapes serve as natural laboratories to investigate biodiversity responses to fragmentation.One of these most iconic landscapes is the Balbina Hydroelectric Reservoir in Brazilian Amazonia,occupying>400000 ha and comprising>3500 forest islands.Here,we synthesise the current knowledge on responses of a wide range of biological groups to insular fragmentation at Balbina.Sampling has largely concentrated on a set of 22 islands and three mainland sites.In total,39 studies were conducted over nearly two decades,covering 17 vertebrate,invertebrate,and plant taxa.Although species responses varied according to taxonomic group,island area was consistently included and played a pivotal role in 66.7%of all studies examining patterns of species diversity.Species persistence was further affected by species traits,mostly related to species capacity to use/traverse the aquatic matrix or tolerate habitat degradation,as noted for species of vertebrates and orchid bees.Further research is needed to improve our understanding of such effects on wider ecosystem functioning.Environmental Impact Assessments must account for changes in both the remaining habitat amount and configuration,and subsequent long-term species losses. 展开更多
关键词 Habitat loss Hydropower dams Landbridge Local extinctions Species-area relationships Species diversity Tropical forests
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Strong evidence for latitudinal diversity gradient in mosses across the world
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作者 Hong Qian Zun Dai Jian Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第4期537-541,共5页
Species richness generally decreases with increasing latitude,a biodiversity gradient that has long been considered as one of the few laws in ecology.This latitudinal diversity gradient has been observed in many major... Species richness generally decreases with increasing latitude,a biodiversity gradient that has long been considered as one of the few laws in ecology.This latitudinal diversity gradient has been observed in many major groups of organisms.In plants,the latitudinal diversity gradient has been observed in vascular plants,angiosperms,ferns,and liverworts.However,a conspicuous latitudinal diversity gradient in mosses at a global or continental scale has not been observed until now.Here,we analyze a comprehensive data set including moss species in each band of 20° in latitude worldwide.Our results show that moss species richness decreases strongly with increasing latitude,regardless of whether the globe is considered as a whole or different longitudinal segments(e.g.,Old World versus New World) are considered separately.This result holds when variation in area size among latitudinal bands is taken into account.Pearson's correlation coefficient between latitude and species richness is-0.99 for both the Northern and Southern Hemispheres.Because bryophytes are an extant lineage of early land plants and because mosses not only include most of extant species of bryophytes but also are important constituents of most terrestrial ecosystems,understanding geographic patterns of mosses is particularly important The finding of our study fills a critical knowledge gap. 展开更多
关键词 BRYOPHYTE Latitudinal diversity gradient MOSS Species density Species diversity
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A novel live attenuated vaccine candidate protects chickens against subtype B avian metapneumovirus
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作者 Lingzhai Meng Mengmeng Yu +15 位作者 Suyan Wang Yuntong Chen Yuanling Bao Peng Liu Xiaoyan Feng Tana He Ru Guo Tao Zhang Mingxue Hu Changjun Liu Xiaole Qi Kai Li Li Gao Yanping Zhang Hongyu Cui Yulong Gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1658-1670,共13页
Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the domi... Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the dominant epidemic strain in China. We developed an attenuated aMPV subtype B strain by serial passaging in Vero cells and evaluated its safety and efficacy as a vaccine candidate. The safety test showed that after the 30th passage, the LN16-A strain was fully attenuated, as clinical signs of infection and histological lesions were absent after inoculation.The LN16-A strain did not revert to a virulent strain after five serial passages in chickens. The genomic sequence of LN16-A differed from that of the parent wild-type LN16(wtLN16) strain and had nine amino acid mutations. In chickens, a single immunization with LN16-A induced robust humoral and cellular immune responses, including the abundant production of neutralizing antibodies, CD4^(+) T lymphocytes, and the Th1(IFN-γ) and Th2(IL-4 and IL-6)cytokines. We also confirmed that LN16-A provided 100% protection against subtype B aMPV and significantly reduced viral shedding and turbinate inflammation. Our findings suggest that the LN16-A strain is a promising live attenuated vaccine candidate that can prevent infection with subtype B aMPV. 展开更多
关键词 avian metapneumovirus ATTENUATED protection vaccine candidate CHICKENS
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Diversity of Orchids in Terms of Their Distribution, Uses and Conservation in Annapurna Conservation Area of Nepal
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作者 Babu Lal Tiruwa Basu Dev Neupane +2 位作者 Rabin Kadariya Chiranjibi Prasad Pokheral Bijaya Pant 《American Journal of Plant Sciences》 CAS 2024年第6期422-440,共19页
The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enou... The Annapurna Conservation Area (ACA), the first conservation area and the largest protected area (PA) in Nepal, is incredibly rich in biodiversity. Notwithstanding this, orchids in the ACA have not been explored enough yet thus making the need for ambitious research to be carried out. Previous study only included 81 species of orchids within ACA. This study aims to update the record of species and genera richness in the ACA. In total 198 species of orchids, belonging to 67 genera (40% and 62% of the total recorded orchid species and genera in Nepal) has been recorded in ACA. This represents an increase of 144% in species and 56% in genera over the previous data. Out of the 198 species, 99 were epiphytes, 6 were holomycotrophic and 93 were terrestrial. Among the 67 genera, Bulbophyllum (17) species were dominant, followed by Dendrobium (16), Herminium (10), Coelogyne, Plantanthera (9 each), Eria, Habenaria, Oberonia (8 each), Calanthe (7), and Liparis (6). Fifty-six species were found to be ornamentally significant and 85 species medicinally significant. 展开更多
关键词 ORCHIDS Annapurna Conservation Area diversity DISTRIBUTION USES
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Genetic Diversity of Jute Mallow (Corchorus spp.) Accessions Based on ISSR Markers
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作者 Munguatosha Ngomuo Tsvetelina Stoilova +1 位作者 Tileye Feyissa Patrick A. Ndakidemi 《American Journal of Plant Sciences》 CAS 2024年第5期316-328,共13页
Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported.... Jute mallow is a nutritious leafy vegetable. The leaves are rich in proteins, vitamins and essential amino acids. Molecular characterization of Jute mallow with focus on improvement of leaf yield is scarcely reported. In the present study, inter sequence simple repeats (ISSR) molecular markers were employed to assess genetic diversity and relationships of 83 accessions of Jute mallow from different parts of Africa and Asia conserved at the World Vegetable Center East and Southern Africa. A total of 89 bands were amplified by 8 ISSR primers. Number of polymorphic bands per primer ranged from 2 to 6 with an average of 2.75 bands per primer. Polymorphic information content (PIC) values ranged from 0.390 to 0.760 with average of 0.53. Average Nei’s gene diversity (h) and Shannon’s information index (I) were 0.335 and 0.494 respectively. The highest pairwise genetic distance was 0.431 observed in a population from East Africa accessions. PC1 and PC2 axis explained 21.69% and 11.66% of the total variation respectively. UPGMA cluster analysis grouped the accessions into six main clusters at genetic similarity coefficient of 0.53 as standard value for classification. These results have important implications for jute mallow breeding and conservation. 展开更多
关键词 Corchorus spp. Genetic diversity ISSRS Jute Mallow Leafy Vegetable
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Genetic and biological properties of H9N2 avian influenza viruses isolated in central China from2020 to 2022
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作者 Libin Liang Yaning Bai +14 位作者 Wenyan Huang Pengfei Ren Xing Li Dou Wang Yuhan Yang Zhen Gao Jiao Tang Xingchen Wu Shimin Gao Yanna Guo Mingming Hu Zhiwei Wang Zhongbing Wang Haili Ma Junping Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第8期2778-2791,共14页
The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by se... The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in China.The H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public health.Currently,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central China.In this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different genotypes.Our study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these birds.These viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and kidneys.At the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular level.The antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic clusters.Our research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central China.It also highlights the necessity of enhancing the surveillance of H9N2 AIVs. 展开更多
关键词 avian influenza virus H9N2 central China PATHOGENICITY ANTIGENICITY
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Genetic Diversity in Cowpea (Vigna unguiculata (L.) Walp) under Two Growing Conditions*
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作者 Omotola Oluwakemi Dairo 《Advances in Bioscience and Biotechnology》 CAS 2024年第5期310-324,共15页
This study explores the use of genetic variability for advancing the genetic improvement of Cowpea (Vigna unguiculata (L.) Walp), particularly in response to insect infestation stress. Over a period spanning 2015 to 2... This study explores the use of genetic variability for advancing the genetic improvement of Cowpea (Vigna unguiculata (L.) Walp), particularly in response to insect infestation stress. Over a period spanning 2015 to 2017, forty accessions of cowpeas were evaluated to determine their variability under both insecticide spray and no insecticide spray conditions at the Teachings and Research Farms, Federal University of Agriculture, Abeokuta. The experimental design was a randomized complete block design in three replicates. The accessions were evaluated for plant height, leaf length, leaf width, number of days of 50% flowering, number of pods per plant, pod length, number of seeds per plant, 100-seed weight, and seed yield. Data collected were subjected to principal component and single linkage cluster analyses. Principal axis I (PCA1) accounted for 39% and 35% under insecticide spray and no insecticide spray respectively to the total variation in the accessions. Plant height with a factor score of 0.38, leaf length (0.41), number of leaves (0.37), and 100-seed, weight (0.30) was related to PCAI under insecticide spray while leaf width (0.32). Pod length (0.37) and number of seeds/plant (0.38) were significant to PCA1 under no insecticide spray. Notably, accessions such as SAMPEA6, SAMPEA10, IFE-Brown, and IFE-BPE exhibited consistent performance across both conditions, while others displayed condition-specific attributes. For instance, NGB1063, NGB1152, and NGB1093 demonstrated distinct traits under insecticide spray, while NGB1146 and NGB1124 exhibited notable characteristics under no insecticide spray conditions. Therefore, identifying these forty accessions with desirable traits hold promise for future genetic improvement efforts of cowpea cultivation in Nigeria and beyond. 展开更多
关键词 COWPEA Vigna Unguiculata Genetic diversity Cowpea Accessions
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Dietary Diversity and Food Security Status among Cameroonian Adults Living in Semi-Urban Areas: A Cross-Sectional Study
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作者 Tonou Boris Ronald Tchuente Pauline Vervaine Hagbe +6 位作者 Eliane Flore Eyenga Kemadjou Ruth Edwige Dibacto Ngassa Dany Joël Ngoumen Fotso Janvier Aime Youovop Nguemto Roussel Guy Takuissu Judith Laure Ngondi Julius Enyong Oben 《Food and Nutrition Sciences》 CAS 2024年第7期548-564,共17页
Introduction: Food security is one of the greatest challenges that most African countries face. It is a concept that considers not only food quantity but also food quality. The objective of this study was to describe ... Introduction: Food security is one of the greatest challenges that most African countries face. It is a concept that considers not only food quantity but also food quality. The objective of this study was to describe dietary diversity and food security status at the individual level in Cameroonian populations. Methods: A total of 1180 men and women aged 20 and over and living in the West, North West, and Littoral regions of Cameroon were recruited. Data on dietary habits were collected through the frequency of consumption of various food groups. Dietary diversity was assessed using a 24-hour dietary recall. Food security status was determined by combining two indicators (food consumption score and individual food diversity score). Results: The mean dietary diversity score of the population was 3.53 ± 1.44, p Conclusion: The diet diversity of adults living in the West, North West, and Littoral regions of Cameroon is medium. Although half of the study population was food secure, there is a need to implement food security policies further to reduce food insecurity among the Cameroonian population. 展开更多
关键词 Dietary diversity Individual Food Security LITTORAL WEST North West Cameroon
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Floristic Diversity, Stand Structure and Plant Life Traits in the Forest-Savanna Mosaic at Ndjole (Centre Cameroon)
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作者 Djeuguen Vanessa Tchaleu Solefack Marie Caroline Momo +3 位作者 Mateso Aimé Kambale Ndondjeu Charles Tafen Yanick Borel Kamga Victor François Nguetsop 《Open Journal of Ecology》 2024年第4期309-330,共22页
With the aim of assessing floristic diversity, stand structure and vegetation ecology, the present work was carried out in the savanna mosaic forest of the locality of Ndjole (Centre Cameroon). A total of 30 floristic... With the aim of assessing floristic diversity, stand structure and vegetation ecology, the present work was carried out in the savanna mosaic forest of the locality of Ndjole (Centre Cameroon). A total of 30 floristic plots of 40 m × 40 m (1600 m<sup>2</sup>) were delineated in the different ecosystems (forest, forest-savanna contact zone and the savanna). Within each plot, all individuals with a diameter at breast height ≥ 10 cm at 1.30 m were taken into account. ANOVA was used to compare the means of the diversity indices of the different ecosystems, and the DUNCAN test at 5% significance level (XLSTAT 2016) to separate these means. A total of 85 species belonging to 67 genera and 33 families were recorded. That is, 68 species in semi-caducifolia forest, 45 in forest-savanna contact zone and 18 in savanna. Urticaceae, Combretaceae, Apocynaceae, Myristicaceae and Euphorbiaceae are the most diverse families in the forest. On the other hand, in contact zones, the Euphorbiaceae, Fabaceae, Annonaceae and Moraceae families are the most diversified, while in the savannas, the Combretaceae, Fabaceae and Annonaceae families are the most diversified. Shannon’s diversity index values (1.7 to 2.37 bits) reflect low specific diversity;Piélou’s equitability (0.86 to 0.9) shows good distribution of individuals within species. The diametric structure of woody species shows an inverted “J” shape in all plant communities. This indicates a high regeneration potential characterized by a greater number of small trees than large trees. Mesophanerophytes and megaphanerophytes are dominant in forests and forest-savanna contact zones, and microphanerophytes in the savannas. Endozoochory is the main mode of diaspore dissemination. As regards the distribution of phytogeographical types, it shows the overall dominance of Guineo-Congolese species in all plant communities. Our study provides detailed data on forest-savanna floristic and plant life traits in the mosaic and recommends further studies on the impact of environmental parameter variations on the forest encroachment into savanna. 展开更多
关键词 MOSAIC COMMUNITIES DISSEMINATION Regeneration diversity
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