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Did Species and Functional Diversities of Sandy Intertidal Marine Nematodes Reveal Similar Response to Environmental Changes?
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作者 SONG Huili MU Fanghong +1 位作者 SUN Yan HUA Er 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期527-540,共14页
Free living marine nematodes were sampled from two sandy beaches in Dalian City,in December of 2015,and April,July,and October of 2016.The spatial and seasonal variations of marine nematode species diversity(based on ... Free living marine nematodes were sampled from two sandy beaches in Dalian City,in December of 2015,and April,July,and October of 2016.The spatial and seasonal variations of marine nematode species diversity(based on species abundance dataset)and functional diversity(based on functional traits dataset:feeding types and life history strategies)were investigated to understand the environmental drivers and how they respond to specific environmental variations.Sediment granularity was revealed to be the main environmental factor causing spatial differences in nematode diversity indices between the two beaches.Species diversity indices,namely species number,Margalef index,Shannon-Wiener diversity index(H’),were higher in fine-grained sediments,while the functional diversity indices,including functional evenness,functional dispersion,and Rao’s quadratic entropy index(RaoQ),were higher in coarse-grained sediments.Nematode species diversity indices also fluctuated with seasonal variations of temperature,dissolved oxygen,pH,salinity,and sediment chlorophyll-a within the study beaches.However,functional diversity indices did not show significant seasonal variations and exhibited weak correlation with the studied environmental variables.Overall,the functional diversity indices were negatively correlated with the species diversity indices,suggesting an inconsistent response to environmental changes.A decrease in nematode species diversity in coarse sands,accompanied by an increase in functional diversity,can be regarded as an early warning signal of environment disturbance.If more biological traits are involved in calculating functional diversity indices,it will be helpful for the future study of the internal connections of species diversity and functional diversity. 展开更多
关键词 marine nematode species diversity functional diversity functional traits sandy beaches
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Research on Genetic Diversities between Xiaogan Water Chestnut and Wild Chestnut by Randomly Amplified Polymorphic DNA Technology 被引量:3
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作者 盛继群 曹姣 李建华 《Agricultural Science & Technology》 CAS 2010年第8期84-86,90,共4页
[Objective] The aim was to study the genetic diversities between Xiaogan water chestnut and wild chestnut with randomly amplified polymorphic DNA (RAPD) technology. [Method] Genetic diversities of the local cultivat... [Objective] The aim was to study the genetic diversities between Xiaogan water chestnut and wild chestnut with randomly amplified polymorphic DNA (RAPD) technology. [Method] Genetic diversities of the local cultivated water chestnut,wild chestnut,Lepironia articulata and Scirpus planiculmis Fr. Schmidt were analyzed by RAPD technology. [Result] Among the screened random primers 841,842,807 and 840,the polymorphism of amplification product of 841 was evident,and the obtained bands in electrophoresis were clear and showed good repeatability. Cluster analysis result showed that the affinity of cultivated water chestnut and wild water chestnut was nearer than that between Lepironia articulata and Scirpus planiculmis. [Conclusion] The research provides theoretical basis for cultivating high-quality new varieties of water chestnut. 展开更多
关键词 Water chestnut RAPD Cluster analysis Genetic diversities
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Control Factors and Diversities of Phase State of Oil and Gas Pools in the Kuqa Petroleum System 被引量:16
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作者 CHEN Ling ZHU Guangyou +2 位作者 ZHANG Bin WEN Zhigang WANG Yonggang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期484-496,共13页
Based on the analysis of the hydrocarbon geochemical characteristics in the Kuqa petroleum system of the Tarim Basin, this study discusses the causes and controlling factors of the phase diversities and their differen... Based on the analysis of the hydrocarbon geochemical characteristics in the Kuqa petroleum system of the Tarim Basin, this study discusses the causes and controlling factors of the phase diversities and their differences in geochemical features. According to the characteristics and differences in oil and gas phase, the petroleum system can be divided into five categories: oil reservoir, wet gas reservoir, condensate gas-rich reservoir, condensate gas-poor reservoir and dry gas reservoir. The causes for the diversities in oil and gas phases include diversities of the sources of parent material, maturity of natural gas and the process of hydrocarbon accumulation of different hydrocarbon phases. On the whole, the Jurassic and Triassic terrestrial source rocks are the main sources for the hydrocarbon in the Kuqa Depression. The small differences in parent material may cause diversities in oil and gas amount, but the impact is small. The differences in oil and gas phase are mainly affected by maturity and the accumulation process, which closely relates with each other. Oil and gas at different thermal evolution stage can be captured in different accumulation process. 展开更多
关键词 Kuqa petroleum system geochemical characteristics of oil and gas diversities of phase state of oil and gas the process of hydrocarbon accumulation
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Analysis of Landscape Diversities in Maolan Forests
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作者 王中强 龙翠玲 +2 位作者 赵晶 王诚曦 龙健 《Journal of Landscape Research》 2010年第2期79-81,86,共4页
With Maolan Nature Reserve as an example, its forest landscape characteristics and diversity were studied by utilizing GIS. The results showed that the overall forest landscape in Maolan Nature Reserve was quite good,... With Maolan Nature Reserve as an example, its forest landscape characteristics and diversity were studied by utilizing GIS. The results showed that the overall forest landscape in Maolan Nature Reserve was quite good, but with the increasing natural interferences and human activities, shrub forests and non-woodland landscape types have been multiplied; among the 3 functional zones of the Nature Reserve, landscape fragmentation degree is low in core zone and buffer zone, but high in experimental zone. 展开更多
关键词 Maolan Nature Reserve Forest landscapes Landscape diversity
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Mobilities, Identities and Diversities: Contemporary Interpretations of a Canonical Chinese Play in Singapore
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作者 Ann-Marie Hsiung 《Sociology Study》 2020年第3期141-148,共8页
Globalization increases mobilities and multiplies identities in Asia.Singapore,a city state with diverse Asian communities,amplifies this trend.In the 1990s,Singapore recruited large numbers of Western educated Chines... Globalization increases mobilities and multiplies identities in Asia.Singapore,a city state with diverse Asian communities,amplifies this trend.In the 1990s,Singapore recruited large numbers of Western educated Chinese scholars,who formed new diasporas across Asia and became catalyst for further cultural diversities.This multifaceted Asian phenomenon can be best exemplified in Chinese scholar-director Grant Shen’s contemporary productions of the traditional Chinese opera—The West Wing(2008,2016).This study discusses issues of mobilities,identities,and diversities through The West Wing,in which the performers are predominantly from Asian diasporas.The mobility of Grant Shen from China to Singapore via the US diversifies his cultural identity,at once rooted deeply in Chinese culture while openly embracing Western liberalism and Singaporean plurality.His theatre productions,boldly adopting pop music,employing trendy language,and recreating pro-feminist scenes,vividly attest to cultural diversities.Identity issues come to the fore when this well-received play in Singapore toured Shanghai,where it was welcomed by the young but frowned upon by others as subversive to Chinese tradition.This study views the multiplicity of Singapore as a fertile land for productions foretelling the plural future Asia. 展开更多
关键词 MOBILITIES IDENTITIES cultural diversities scholar-director canonic drama
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Bacterial and cyanobacterial diversities determined by T-RFLP analyses in the Jiaozhou Bay 被引量:4
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作者 REN Jing DANG Hongyue +2 位作者 SONG Linsheng SUN Song AN Liguo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第4期113-123,共11页
The methods of DAPI staining epifluorescence microscopy and T-RFLP analysis were used to analyze the microbial abundance and diversity in surface seawater sampled from 12 stations inside and outside of the Jiaozhou Ba... The methods of DAPI staining epifluorescence microscopy and T-RFLP analysis were used to analyze the microbial abundance and diversity in surface seawater sampled from 12 stations inside and outside of the Jiaozhou Bay during a survey on 12 and 13 September 2004. The abundance of total microbes is in the range of 10^6~ 10^7 cells/cm^3, similar to those of most semi-enclosed bays in the temperate areas in the world. The highest microbial densities occur in the northeastern part of the Jiaozhou Bay, around the mouths of Loushan and Licun Rivers and the Hongdao aquacultural farming areas, suggesting that the degree and characteristics of pollutions, along with geographical and hydrological effects, may be important determinants affecting the abundance and distribution of bacteria in the Jiaozhou Bay. Bacterial communities inside and outside of the Jiaozhou Bay can be grouped into three classes based on T-RFLP patterns and cluster analyses. Stations at the water channel of the bay mouth and outside, such as D1, D3, D5, D6 and D7, are grouped together to stand for the outside bacterial community interacting with the environment outside of the Jiaozhou Bay. Stations of the innermost side of the Jiaozhou Bay, such as A3, A5, B2 and Y1, are grouped together to stand for the residential bacteria community. Stations C1, C3 and CA are grouped together and may stand for the transitional bacterial assemblage between the residential community and the outside community. However, there is no such a defined relationship for the case of cyanobacterial diversity, indicating the fact that cyanobacteria are more flexible and adaptable to all kinds of conditions. 展开更多
关键词 bacterial diversity CYANOBACTERIA 16S rDNA T-RFLP Jiaozhou Bay
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The Study of Diversities of Marine Microbes in China 被引量:2
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作者 ZHANG Si ZHANG Changsheng TIAN Xinpeng WANG Fazuo LI Jie 《Bulletin of the Chinese Academy of Sciences》 2010年第4期228-234,共7页
The oceans account for 71% of the Earth’s surface and are rich in the most advantageous and characteristic resources of marine microbes. The research on diversity is the key point for exploring and exploiting marine ... The oceans account for 71% of the Earth’s surface and are rich in the most advantageous and characteristic resources of marine microbes. The research on diversity is the key point for exploring and exploiting marine microbial resources. Giving attention to species diversity and genetic diversity of marine microbes, discovering novel metabolites with multiple functions, revealing key secondary metabolic process and the main regulation mechanisms in marine microbes, and developing a new technology of biosynthesis, are the important foundation for discovering innovative drugs and developing functional products with characteristics. The present paper has reviewed the recent advances in the four research areas of marine microbial species diversity, genetic diversity, chemical diversity and metabolic diversity in China. 展开更多
关键词 marine microbes DIVERSITY SPECIES GENETIC CHEMICAL METABOLIC
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Characterization of Genetic and Phenotypic Diversities in the Potato (Solanum tuberosum L.) Population in Kosovo
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作者 S. A. Aliu Sh. Sh. Fetahu I. R. Rusinovci B. H. Zogaj 《Journal of Agricultural Science and Technology(B)》 2011年第6期925-931,共7页
The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to loc... The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to local fanning system and specific agro ecological conditions. This research was conducted in Prishtina region which is located in the Kosovo agro ecological region (42°38′97″ latitude and 21°08′45" longitude at 574 m.a.s.l ). Plant material used in this research was 18 potato accessions with different origins. The experimental design was a randomized complete block (RCB) with three replicates, while the plot sizes were 4.20 m^2. All observation and analysis were carried out on 12 plants from each accession. All characters were measured in the field and laboratory at the normal harvest time. Morphological diversity was characterized using standard descriptors. The genetic diversity studies of the investigated potato accessions showed significant genetic variation on 17 physiological and chemical parameters, which could be largely due to that they were of different origins. The genetic diversity of potato cultivars offers a wealth of natural resources from which breeders can select the most desirable genotypes based on their favorable traits. 展开更多
关键词 POTATO ACCESSION DESCRIPTORS diversity minerals.
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Two diversities meet in the rhizosphere:root specialized metabolites and microbiome 被引量:1
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作者 Xiaochen Wang Jingying Zhang +2 位作者 Xinjun Lu Yang Bai Guodong Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第5期467-478,共12页
Plants serve as rich repositories of diverse chemical compounds collectively referred to as specialized metabolites.These compounds are of importance for adaptive processes,including interactions with various microbes... Plants serve as rich repositories of diverse chemical compounds collectively referred to as specialized metabolites.These compounds are of importance for adaptive processes,including interactions with various microbes both beneficial and harmful.Considering microbes as bioreactors,the chemical diversity undergoes dynamic changes when root-derived specialized metabolites(RSMs)and microbes encounter each other in the rhizosphere.Recent advancements in sequencing techniques and molecular biology tools have not only accelerated the elucidation of biosynthetic pathways of RSMs but also unveiled the significance of RSMs in plant-microbe interactions.In this review,we provide a comprehensive description of the effects of RSMs on microbe assembly in the rhizosphere and the influence of corresponding microbial changes on plant health,incorporating the most up-to-date information available.Additionally,we highlight open questions that remain for a deeper understanding of and harnessing the potential of RSM-microbe interactions to enhance plant adaptation to the environment.Finally,we propose a pipeline for investigating the intricate associations between root exometabolites and the rhizomicrobiome. 展开更多
关键词 Root specialized metabolites MICROBIOME Plant-microbe interactions RHIZOSPHERE DIVERSITY
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Combined effects of climate and land-use changes on the alpha and beta functional diversities of terrestrial mammals in China
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作者 Chao Zhang Yumei Li +3 位作者 Wei Wang Zexuan Gao Hanqing Liu Yonggang Nie 《Science China(Life Sciences)》 SCIE CAS CSCD 2024年第10期2224-2233,共10页
Climate and land-use changes are predicted to impact biodiversity,threatening ecosystem services and functions.However,their combined effects on the functional diversity of mammals at the regional scale remain unclear... Climate and land-use changes are predicted to impact biodiversity,threatening ecosystem services and functions.However,their combined effects on the functional diversity of mammals at the regional scale remain unclear,especially at the beta level.Here,we use projected climate and land-use changes in China to investigate their potential effects on the alpha and beta functional diversities of terrestrial mammals under low-and high-emission scenarios.In the current projection,we showed strong positive spatial correlations between functional richness and species richness.Functional evenness(FEve),functional specialization(FSpe),and functional originality(FOri)decreased with species richness,and functional divergence(FDiv)increased first and then plateaued.Functional beta diversity was dominated by its nestedness component,in contrast to the taxonomic facet.Potential changes in species richness are more strongly influenced by land-use change under the low-emission scenario,while under the high-emission scenario,they are more strongly influenced by climate change.Changes in functional richness(FRic)were inconsistent with those in species richness,with a magnitude of decreases greater than predicted from species richness.Moreover,mammal assemblages showed potential functional differentiation(FD)across the country,and the trends exceeded those towards taxonomic differentiation(TD).Our findings help us understand the processes underlying biodiversity responses to global changes on multiple facets and provide new insight for conservation plans. 展开更多
关键词 climate change land-use change functional diversity terrestrial mammals biodiversity conservation
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Unexpected divergence in magnetoreceptor MagR from robin and pigeon linked to two sequence variations 被引量:3
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作者 Shun Wang Peng Zhang +12 位作者 Fan Fei Tianyang Tong Xiujuan Zhou Yajie Zhou Jing Zhang Mengke Wei Yanqi Zhang Lei Zhang Yulong Huang Lin Zhang Xin Zhang Tiantian Cai Can Xie 《Zoological Research》 SCIE CSCD 2024年第1期69-78,共10页
Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity i... Birds exhibit extraordinary mobility and remarkable navigational skills,obtaining guidance cues from the Earth’s magnetic field for orientation and long-distance movement.Bird species also show tremendous diversity in navigation strategies,with considerable differences even within the same taxa and among individuals from the same population.The highly conserved iron and iron-sulfur cluster binding magnetoreceptor(MagR)protein is suggested to enable animals,including birds,to detect the geomagnetic field and navigate accordingly.Notably,MagR is also implicated in other functions,such as electron transfer and biogenesis of iron-sulfur clusters,raising the question of whether variability exists in its biochemical and biophysical features among species,particularly birds.In the current study,we conducted a comparative analysis of MagR from two different bird species,including the migratory European robin(Erithacus rubecula)and the homing pigeon(Columba livia).Sequence alignment revealed an extremely high degree of similarity between the MagRs of these species,with only three sequence variations.Nevertheless,two of these variations underpinned significant differences in metal binding capacity,oligomeric state,and magnetic properties.These findings offer compelling evidence for the marked differences in MagR between the two avian species,potentially explaining how a highly conserved protein can mediate such diverse functions. 展开更多
关键词 Homing and migration Animal navigation Magnetoreceptor(MagR) Diverse navigation pattern Conserved protein
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Superiority of a Convolutional Neural Network Model over Dynamical Models in Predicting Central Pacific ENSO 被引量:2
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作者 Tingyu WANG Ping HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期141-154,共14页
The application of deep learning is fast developing in climate prediction,in which El Ni?o–Southern Oscillation(ENSO),as the most dominant disaster-causing climate event,is a key target.Previous studies have shown th... The application of deep learning is fast developing in climate prediction,in which El Ni?o–Southern Oscillation(ENSO),as the most dominant disaster-causing climate event,is a key target.Previous studies have shown that deep learning methods possess a certain level of superiority in predicting ENSO indices.The present study develops a deep learning model for predicting the spatial pattern of sea surface temperature anomalies(SSTAs)in the equatorial Pacific by training a convolutional neural network(CNN)model with historical simulations from CMIP6 models.Compared with dynamical models,the CNN model has higher skill in predicting the SSTAs in the equatorial western-central Pacific,but not in the eastern Pacific.The CNN model can successfully capture the small-scale precursors in the initial SSTAs for the development of central Pacific ENSO to distinguish the spatial mode up to a lead time of seven months.A fusion model combining the predictions of the CNN model and the dynamical models achieves higher skill than each of them for both central and eastern Pacific ENSO. 展开更多
关键词 ENSO diversity deep learning ENSO prediction dynamical forecast system
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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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Historical biogeography and evolutionary diversification of Lilium(Liliaceae): New insights from plastome phylogenomics 被引量:1
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作者 Nian Zhou Ke Miao +4 位作者 Changkun Liu Linbo Jia Jinjin Hu Yongjiang Huang Yunheng Ji 《Plant Diversity》 SCIE CAS CSCD 2024年第2期219-228,共10页
Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were n... Here, we infer the historical biogeography and evolutionary diversification of the genus Lilium. For this purpose, we used the complete plastomes of 64 currently accepted species in the genus Lilium(14plastomes were newly sequenced) to recover the phylogenetic backbone of the genus and a timecalibrated phylogenetic framework to estimate biogeographical history scenarios and evolutionary diversification rates of Lilium. Our results suggest that ancient climatic changes and geological tectonic activities jointly shaped the distribution range and drove evolutionary radiation of Lilium, including the Middle Miocene Climate Optimum(MMCO), the late Miocene global cooling, as well as the successive uplift of the Qinghai-Tibet Plateau(QTP) and the strengthening of the monsoon climate in East Asia during the late Miocene and the Pliocene. This case study suggests that the unique geological and climatic events in the Neogene of East Asia, in particular the uplift of QTP and the enhancement of monsoonal climate, may have played an essential role in formation of uneven distribution of plant diversity in the Northern Hemisphere. 展开更多
关键词 Asian monsoon Climatic changes Distribution range Evolutionary complexity Radiative diversification Species diversity Qinghai-Tibet Plateau(QTP)
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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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Association between childhood obesity and gut microbiota:16S rRNA gene sequencing-based cohort study 被引量:1
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作者 Xu-Ming Li Qing Lv +2 位作者 Ya-Jun Chen Lu-Biao Yan Xin Xiong 《World Journal of Gastroenterology》 SCIE CAS 2024年第16期2249-2257,共9页
BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevent... BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA sequencing.The research aimed to provide insights for mechanistic studies and prevention strategies for childhood obesity.Thirty normal-weight and thirty age-and sex-matched obese children were included.Questionnaires and body measurements were collected,and fecal samples underwent 16S rDNA sequencing.Significant differences in body mass index(BMI)and body-fat percentage were observed between the groups.Analysis of gut microbiota diversity revealed lowerα-diversity in obese children.Differences in gut microbiota composition were found between the two groups.Prevotella and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control group.AIM To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood obesity.METHODS Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,respectively.Basic information was collected through questionnaires and body measurements were obtained from both obese and normal-weight children.Fecal samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity analysis.RESULTS Significant differences in BMI and body-fat percentage were observed between the two groups.The Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson indices.Kruskal-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggesting substantial disparities in both the species and quantity of gut microbiota between the two groups.Prevotella,Firmicutes,Bacteroides,and Sanguibacteroides were more abundant in the obese and control groups,respectively.Heatmap results demonstrated significant differences in the gut microbiota composition between obese and normal-weight children.CONCLUSION Obese children exhibited lowerα-diversity in their gut microbiota than did the normal-weight children.Significant differences were observed in the composition of gut microbiota between obese and normal-weight children. 展开更多
关键词 Childhood obesity Gut microbiota 16S rDNA sequencing Diversity analysis Genus identification Body mass index
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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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