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Island biogeography theory and the habitat heterogeneity jointly explain global patterns of Rhododendron diversity
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作者 Yanwei Guan Yongru Wu +4 位作者 Zheng Cao Zhifeng Wu Fangyuan Yu Haibin Yu Tiejun Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第5期565-574,共10页
Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diver... Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diversity.In this study,we determined which of six common hypotheses(e.g.,climate hypotheses,habitat heterogeneity hypothesis and island biogeography theory)best explain global patterns of species diversity in Rhododendron.We found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory(i.e.,mountain area)and habitat heterogeneity(i.e.,elevation range).When we examined other relationships important to island biogeography theory,we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity,whereas the‘mountains-to-mainland’distance was negatively correlated with Rhododendron diversity and shared species.Our findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity,and mountains can be regarded as islands which supported island biogeography theory. 展开更多
关键词 Mountain biodiversity RHODODENDRON island biogeography theory Habitat heterogeneity Biogeographical hypotheses Plant diversity
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TIL20: A review of island biogeography and habitat fragmentation studies on subtropical reservoir islands of Thousand Island Lake, China
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作者 Xingfeng Si Tinghao Jin +7 位作者 Wande Li Peng Ren Qiang Wu Di Zeng Xue Zhang Yuhao Zhao Chen Zhu Ping Ding 《Zoological Research(Diversity and Conservation)》 2024年第2期89-105,共17页
Reservoir islands formed by dam construction have the same history,clear boundaries,and large numbers that provide a natural platform for testing theories in ecology and biogeography.In this paper,we review studies of... Reservoir islands formed by dam construction have the same history,clear boundaries,and large numbers that provide a natural platform for testing theories in ecology and biogeography.In this paper,we review studies of multiple zoological taxa on reservoir islands of a large lake in eastern China(Thousand Island Lake).This lake,created in 1959,has 1078 artificial land-bridge islands of varying areas and isolation.Our review summarizes the decades-long studies in island biogeography and habitat fragmentation from this island system,grouped into three topics:species richness(“how many species are there”),community structure(“who are they”),and species interaction(“how they interact with each other”).Our findings support the predictions of the Equilibrium Theory of Island Biogeography and extend this theory to predict community structure of island faunas by moving beyond assumptions of species equivalency.In addition,the extensive studies on ecological networks,including mutualistic,antagonistic,and parasitic interactions,reveal the negative impacts of habitat loss on the maintenance of such networks,even as increasing forest edge enhances the robustness of pollination networks.At the end of this review,we proposed several future research directions based on current studies that are simultaneously at the frontier of ecology and biogeography. 展开更多
关键词 Biodiversity conservation Community assembly Species extinction island Species interaction
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Do Geographically Isolated Grasslands Follow the Principle of Island Biogeography in a Landscape Scale? Taking Poyang Lake Grassland as an Example
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作者 Shiqi Luo Wenbo Chen +1 位作者 Lei He Qiongbing Xiong 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第2期455-470,共16页
As one of the basic theories of biodiversity conservation,island biogeography has been widely accepted in the past decades.Originally,island biogeography was put forward and applied in oceanic environments.But later o... As one of the basic theories of biodiversity conservation,island biogeography has been widely accepted in the past decades.Originally,island biogeography was put forward and applied in oceanic environments.But later on,it was found out that the application was not only limited to oceanic islands,but also in terrestrial environments with relatively isolated conditions.In terms of biodiversity level,island biogeography generally focuses on a small scale,such as species diversity and genetic diversity.The studies of biodiversity on a large-scale based on island biogeography,such as ecosystem and landscape scales,were seldomly conducted.Taking Poyang Lake,the largest fresh water lake in China as case study area,30 grasslands were randomly selected to study whether island biogeography can be applied to grasslands at a landscape level from three island attributes(area,distance and shape),and the most important ecological variable(flooding)in Poyang Lake.The results showed that in general,grasslands have the property of an island,and follow the basic principle of island biogeography.We found the area and flooding duration were the two most important determinants of landscape diversity.There was a significant positive correlation between the grassland area and the landscape diversity,which could be well expressed by logarithmic function model(R2=0.73).There was a negative correlation between flooding duration and landscape diversity,which could be described by an inverse model(R2=0.206).The distance to mainland and the shape of grassland were correlated with landscape diversity,but the fitting result of the models was not as good as expected.The possible reason could be that Poyang Lake is a seasonal lake,the water level varies with hydrological conditions,so that the grasslands are not strongly isolated and their shape is not stable enough required by island biogeography.Furthermore,it indicates that besides area,distance and shape attributes,flooding strongly affects the biodiversity of grassland vegetation,and should not be ignored when applying island biogeography theory to Poyang Lake.This study is expected to be a supplement for island biogeography in terrestrial environments,and the results are expected to benefit for the biodiversity conservation in Poyang Lake. 展开更多
关键词 island attribute landscape diversity GRASSLAND FLOODING Poyang Lake
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Integrative biogeography: Validating hypotheses of species distribution 被引量:1
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作者 Zhong-E Hou Shu-Qiang Li 《Zoological Research(Diversity and Conservation)》 2024年第1期86-88,共3页
DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&... DEAR EDITOR,Biogeography is a scientific field dedicated to the investigation of the origins and distribution patterns of organisms,as well as predicting future alterations in their geographical distributions(Cox&Moore,2005).However,the majority of conclusions drawn within the field of biogeography are hypothetical.Rigorous testing of these biogeographic hypotheses remains a considerable challenge.This paper presents the concept of“integrative biogeography”,which emphasizes the experimental testing of biogeographic hypotheses through studies on geological history,as well as biotic and abiotic factors(Figure 1). 展开更多
关键词 biogeography DISTRIBUTION DATING
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Genetic evaluations of island populations of Rhesus Macaque (Macaca mulatta) in China: Implications for conservation management 被引量:1
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作者 Ning-Xin Gu Yang Liu 《Zoological Research(Diversity and Conservation)》 2024年第1期75-78,共4页
DEAR EDITOR,The macaques belongs to the genus Macaca,consisting of at least 23 species(Roos et al.,2019).Among all congeners,rhesus macaque(M.mulatta)is regarded as the widest distributed non-human primate species in ... DEAR EDITOR,The macaques belongs to the genus Macaca,consisting of at least 23 species(Roos et al.,2019).Among all congeners,rhesus macaque(M.mulatta)is regarded as the widest distributed non-human primate species in the world.Its native range spans in East Asia,northern part of Southeast Asia and Indian subcontinent(Liu et al.,2018).Listed as“Least Concern”on the IUCN Red List,this species is locally threatened due to habitat loss and degradation in China and Thailand(Lu et al.,2018).Nevertheless,pet release resulting in hybridization with other congeners(e.g.,rhesus macaque×crab-eating macaque(M.fascicularis))was documented in Hong Kong SAR,China(Wong&Ni,2000),threatening genetic integrity of wild populations. 展开更多
关键词 MACACA HABITAT island
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Progress in systematics and biogeography of Orchidaceae
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作者 Yajun Wang Hanchen Wang +4 位作者 Chao Ye Zhiping Wang Chongbo Ma Dongliang Lin Xiaohua Jin 《Plant Diversity》 SCIE CAS CSCD 2024年第4期425-434,共10页
Orchidaceae are one of the largest families of angiosperms in terms of species richness.In the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data fro... Orchidaceae are one of the largest families of angiosperms in terms of species richness.In the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data from plastid,mitochondrial and nuclear sources.These studies have provided new insights into the systematics,diversification and biogeography of Orchidaceae,establishing a robust foundation for future research.Nevertheless,pronounced controversies persist regarding the precise placement of certain lineages within these phylogenetic frameworks.To address these discrepancies and deepen our understanding of the phylogenetic structure of Orchidaceae,we provide a comprehensive overview and analysis of phylogenetic studies focusing on contentious groups within Orchidaceae since 2015,delving into discussions on the underlying reasons for observed topological conflicts.We also provide a novel phylogenetic framework at the subtribal level.Furthermore,we examine the tempo and mode underlying orchid species diversity from the perspective of historical biogeography,highlighting factors contributing to extensive speciation.Ultimately,we delineate avenues for future research aimed at enhancing our understanding of Orchidaceae phylogeny and diversity. 展开更多
关键词 Diversification Orchid phylogenetics Phylogenetic conflicts biogeography Taxonomy
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Drivers,Trends,and Patterns of Changing Vegetation-greenness in Nansha Islands,China from 2016 to 2022
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作者 TANG Jiasheng FU Dongjie +2 位作者 SU Fenzhen YU Hao WANG Xinhui 《Chinese Geographical Science》 SCIE CSCD 2024年第4期662-673,共12页
Changes in vegetation status generally also represents changes in the ecological health of islands and reefs(IRs).However,studies are limited of drivers and trends of vegetation change of Nansha Islands,China and how ... Changes in vegetation status generally also represents changes in the ecological health of islands and reefs(IRs).However,studies are limited of drivers and trends of vegetation change of Nansha Islands,China and how they relate to climate change and human activities.To resolve this limitation,we studied changes to the Normalized Difference Vegetation Index(NDVI)vegetation-greenness index for 22 IRs of Nansha Islands during normal and extreme conditions.Trends of vegetation greenness were analyzed using Sen's slope and Mann-Kendall test at two spatial scales(pixel and island),and driving factor analyses were performed by time-lagged partial correlation analyses.These were related to impacts from human activities and climatic factors under normal(temperature,precipitation,radiation,and Normalized Difference Built-up Index(NDBI))and extreme conditions(wind speed and latitude of IRs)from 2016 to 2022.Results showed:1)among the 22 IRs,NDVI increased/decreased significantly in 15/4 IRs,respectively.Huayang Reef had the highest NDVI change-rate(0.48%/mon),and Zhongye Island had the lowest(–0.29%/mon).Local spatial patterns were in one of two forms:dotted-form,and degradation in banded-form.2)Under normal conditions,human activities(characterized by NDBI)had higher impacts on vegetation-greenness than other factors.3)Under extreme conditions,wind speed(R^(2)=0.2337,P<0.05)and latitude(R^(2)=0.2769,P<0.05)provided limited explanation for changes from typhoon events.Our results provide scientific support for the sustainable development of Nansha Islands and the United Nations‘Ocean Decade’initiative. 展开更多
关键词 island and reefs(IRs) Normalized Difference Vegetation Index(NDVI) vegetation-greenness change-rate Sen's slope Nansha islands China
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Local Climate Change Induced by Urbanization on a South China Sea Island
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作者 郝宇 李磊 +2 位作者 陈柏纬 孙伟 戴永久 《Journal of Tropical Meteorology》 SCIE 2024年第1期11-19,共9页
The South China Sea is a hotspot for regional climate research.Over the past 40 years,considerable improvement has been made in the development and utilization of the islands in the South China Sea,leading to a substa... The South China Sea is a hotspot for regional climate research.Over the past 40 years,considerable improvement has been made in the development and utilization of the islands in the South China Sea,leading to a substantial change in the land-use of the islands.However,research on the impact of human development on the local climate of these islands is lacking.This study analyzed the characteristics of local climate changes on the islands in the South China Sea based on data from the Yongxing Island Observation Station and ERA5 re-analysis.Furthermore,the influence of urbanization on the local climate of the South China Sea islands was explored in this study.The findings revealed that the 10-year average temperature in Yongxing Island increased by approximately 1.11℃from 1961 to 2020,and the contribution of island development and urbanization to the local warming rate over 60 years was approximately 36.2%.The linear increasing trend of the annual hot days from 1961–2020 was approximately 14.84 days per decade.The diurnal temperature range exhibited an increasing trend of 0.05℃per decade,whereas the number of cold days decreased by 1.06days per decade.The rapid increase in construction on Yongxing Island from 2005 to 2021 led to a decrease in observed surface wind speed by 0.32 m s^(-1)per decade.Consequently,the number of days with strong winds decreased,whereas the number of days with weak winds increased.Additionally,relative humidity exhibited a rapid decline from 2001 to 2016 and then rebounded.The study also found substantial differences between the ERA5 re-analysis and observation data,particularly in wind speed and relative humidity,indicating that the use of re-analysis data for climate resource assessment and climate change evaluation on island areas may not be feasible. 展开更多
关键词 local climate climate change Yongxing island a South China Sea island climate change induced by urbanization
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Characteristics of divertor heat flux distribution with an island divertor configuration on the J-TEXT tokamak
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作者 Yutong YANG Yunfeng LIANG +8 位作者 Wei YAN Shuangbao SHU Jiankun HUA Song ZHOU Qinghu YANG Jinlong GUO Ziyang JIN Wei XIE the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期9-17,共9页
On J-TEXT,the temporal evolution of heat flux distribution on the high-field side(HFS)divertor plate has been measured by an infrared(IR)camera during the plasma operation with an island divertor configuration.In expe... On J-TEXT,the temporal evolution of heat flux distribution on the high-field side(HFS)divertor plate has been measured by an infrared(IR)camera during the plasma operation with an island divertor configuration.In experiments,the island divertor configuration is an edge magnetic island chain structure surrounded by stochastic layers,which can be induced by resonant magnetic perturbations(RMPs).The experimental results show that the heat flux distribution on the HFS target plate depends significantly on the edge magnetic topology.Furthermore,the impact of hydrogen fueling using supersonic molecular beam injection(SMBI)on the divertor heat flux distributions is studied on J-TEXT with an island divertor configuration.It has been observed that power detachment can be achieved when the radiation front approaches the last closed flux surface(LCFS)after each SMBI pulse.This result may provide a method of access for divertor detachment on a fusion device with a three-dimensional(3D)boundary magnetic structure. 展开更多
关键词 infrared camera island divertor heat flux SMBI power detachment
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Macroinvertebrate Community in Streams on the Canary Islands: Gradient Analysis and Stressors
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作者 Volker Lüderitz Uta Langheinrich +2 位作者 José María Fernández-Palacios Cristina González-Montelongo José Ramón Arévalo 《Natural Science》 2024年第10期183-201,共19页
This study describes the gradient analysis of the freshwater macroinvertebrate assemblages in eight streams of Tenerife and La Gomera (Canary Islands) over a 16-year period. During this period, a total of 75 taxa belo... This study describes the gradient analysis of the freshwater macroinvertebrate assemblages in eight streams of Tenerife and La Gomera (Canary Islands) over a 16-year period. During this period, a total of 75 taxa belonging to 34 taxonomic families were found. Endemism has an important presence in the streams on both islands, especially regarding Trichoptera and Coleoptera. The overall status of freshwater macroinvertebrates is rather uncertain as recent data on these communities are scarce and focused on a limited number of sites. Overexploitation of aquifers and the diversion of natural water flows for irrigation have resulted in the drying up of numerous natural streams, inevitably endangering the fauna that inhabits them. A reduction in number and abundance of endemic and sensitive species was observed in the majority of the sampled streams resulting in a lower ecological rating. Therefore, it is proposed that the protection of streams of high conservation value is essential to conserve freshwater macroinvertebrate fauna native to the Canary Islands. 展开更多
关键词 Canary islands Degradation Diversity ENDEMISM Freshwater Streams MACROINVERTEBRATES
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Coulomb-assisted nonlocal electron transport between two pairs of Majorana bound states in a superconducting island
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作者 王浩迪 任俊潼 +1 位作者 吕海峰 柯莎莎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期275-279,共5页
We investigate the nonlocal transport modulated by Coulomb interactions in devices comprising two interacting Majorana wires,where both nanowires are in proximity to a mesoscopic superconducting(SC)island.Each Majoran... We investigate the nonlocal transport modulated by Coulomb interactions in devices comprising two interacting Majorana wires,where both nanowires are in proximity to a mesoscopic superconducting(SC)island.Each Majorana bound state(MBS)is coupled to one lead via a quantum dot with resonant levels.In this device,the nonlocal correlations can be induced in the absence of Majorana energy splitting.We find that the negative differential conductance and giant current noise cross correlation could be induced,due to the interplay between nonlocality of MBSs and dynamical Coulomb blockade effect.This feature may provide a signature for the existence of the MBSs. 展开更多
关键词 Majorana bound states superconducting island current cross correlation
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U-Pb zircon geochronology of basaltic pyroclastic rocks from the basement beneath the Xisha Islands in the northwestern South China Sea and its geological significance
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作者 Yu Zhang Kefu Yu Shiying Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期83-93,共11页
As one of the micro-blocks dispersed in the South China Sea(SCS), the basement of the Xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding ... As one of the micro-blocks dispersed in the South China Sea(SCS), the basement of the Xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding of the pre-Cenozoic basement of the Xisha Islands. Well CK-1, a kilometer-scale major scientific drill in the Xisha Islands in the northwestern SCS, penetrated thick reefal limestone(0–888.4 m) and the underlying basement rocks(888.4–901.4 m). In this study, we present the zircon U-Pb ages of basement basaltic pyroclastic rocks from Well CK-1 in the Xisha Islands of the northwestern SCS to investigate the basement nature of the Xisha microblock. The basement of Well CK-1 consists of basaltic pyroclastic rocks on the seamount. The zircon grains yielded apparent ages ranging from ca. 2 138.9 Ma to ca. 36 Ma. The old group of zircon grains from Well CK-1 was considered to be inherited zircons. Two Cenozoic zircons gave a weighted mean 206Pb/238U age of(36.3 ± 1.1) Ma,Mean Squared Weighted Deviations(MSWD) = 1.2, which may represent the maximum age of the volcano eruption. The Yanshanian inherited zircons(116.9–105.7 Ma and 146.1–130.2 Ma) from Well CK-1 are consistent with the zircons from Well XK-1, indicating that the basement of Chenhang Island may be similar to that of Well XK-1. We propose that the Xisha micro-block may have developed on a uniform Late Jurassic metamorphic crystalline basement, intruded by Cretaceous granitic magma. 展开更多
关键词 South China Sea Xisha islands basaltic pyroclastic rocks ZIRCON
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Factors Influencing the Spatial Variability of Air Temperature Urban Heat Island Intensity in Chinese Cities
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作者 Heng LYU Wei WANG +3 位作者 Keer ZHANG Chang CAO Wei XIAO Xuhui LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期817-829,共13页
Few studies have investigated the spatial patterns of the air temperature urban heat island(AUHI)and its controlling factors.In this study,the data generated by an urban climate model were used to investigate the spat... Few studies have investigated the spatial patterns of the air temperature urban heat island(AUHI)and its controlling factors.In this study,the data generated by an urban climate model were used to investigate the spatial variations of the AUHI across China and the underlying climate and ecological drivers.A total of 355 urban clusters were used.We performed an attribution analysis of the AUHI to elucidate the mechanisms underlying its formation.The results show that the midday AUHI is negatively correlated with climate wetness(humid:0.34 K;semi-humid:0.50 K;semi-arid:0.73 K).The annual mean midnight AUHI does not show discernible spatial patterns,but is generally stronger than the midday AUHI.The urban–rural difference in convection efficiency is the largest contributor to the midday AUHI in the humid(0.32±0.09 K)and the semi-arid(0.36±0.11 K)climate zones.The release of anthropogenic heat from urban land is the dominant contributor to the midnight AUHI in all three climate zones.The rural vegetation density is the most important driver of the daytime and nighttime AUHI spatial variations.A spatial covariance analysis revealed that this vegetation influence is manifested mainly through its regulation of heat storage in rural land. 展开更多
关键词 air temperature urban heat island spatial variations biophysical drivers Chinese cities climate model
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Gyrokinetic simulation of magnetic-island-induced electric potential vortex mode
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作者 王丰 李继全 +1 位作者 曲洪鹏 彭晓东 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期34-41,共8页
Ion temperature gradient(ITG)-driven turbulence with embedded static magnetic islands is simulated by utilizing a gyrokinetic theory-based global turbulence transport code(GKNET)in this work.Different from the traditi... Ion temperature gradient(ITG)-driven turbulence with embedded static magnetic islands is simulated by utilizing a gyrokinetic theory-based global turbulence transport code(GKNET)in this work.Different from the traditional equilibrium circular magnetic-surface average(EMSA)method,an advanced algorithm that calculates the perturbed magnetic-surface average(PMSA)of the electric potential has been developed to precisely deal with the zonal flow component in a non-circular magnetic surface perturbed by magnetic islands.Simulations show that the electric potential vortex structure inside islands induced by the magnetic islands is usually of odd parity when using the EMSA method.It is found that the odd symmetry vortex can transfer into an even one after a steep zonal flow gradient,i.e.the flow shear has been built in the vicinity of the magnetic islands by adopting the PMSA algorithm.The phase of the potential vortex in the poloidal cross section is coupled with the zonal flow shear.Such an electric potential vortex mode may be of essential importance in wide topics,such as the turbulence spreading across magnetic islands,neoclassical tearing mode physics,and also the interaction dynamics between the micro-turbulence and MHD activities. 展开更多
关键词 magnetic islands electric vortex ITG perturbed magnetic flux surface average
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Effect of Moringa oleifera on semen quality profiles in endangered Teressa goat under tropical humid island ecosystem
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作者 P.Perumal Jai Sunder +4 位作者 A.K.De A.K.Nahak D.K.Chaurasia T.C.Balamurugan D.Bhattacharya 《Asian pacific Journal of Reproduction》 CAS 2024年第2期89-96,共8页
Objective:To investigate the effect of Moringa oleifera leaf extract on semen quality parameters in Teressa goat buck.Methods:A total of 25 semen samples from six bucks were selected for the study.Spermatozoa of 150&#... Objective:To investigate the effect of Moringa oleifera leaf extract on semen quality parameters in Teressa goat buck.Methods:A total of 25 semen samples from six bucks were selected for the study.Spermatozoa of 150×10^(6) were incubated in 0,300,500 and 700μg of leaf extract as groupⅠ,Ⅱ,Ⅲ and Ⅳ,respectively.Liquid stored semen samples were analysed for motility,viability,total sperm abnormalities,plasma membrane,acrosomal and nuclear integrities,seminal plasma intracellular enzymes[aspartate aminotransferase(AST),alanine aminotransferase(ALT)and lactate dehydrogenase(LDH)]and total antioxidant capacity(TAC)and spermatozoa malondialdehyde(MDA)and cholesterol efflux in comparison with the control group(groupⅠ)for up to 72 h.Results:Moringa oleifera leaf extract(500μg/150×10^(6) spermatozoa)-treated semen had significantly higher motility,viability,plasma membrane,acrosomal and nuclear integrities,and TAC(P<0.05),and had significantly lower total sperm abnormalities,AST,ALT,LDH,MDA production and cholesterol efflux compared to those in other Moringa oleifera leaf extract treated(300 or 700μg/150×10^(6) spermatozoa)and control groups at different hours of liquid storage(P<0.05).Semen quality parameters and TAC showed an increasing trend and total sperm abnormalities,MDA production,leakage of intra-cellular enzymes and cholesterol efflux showed a decreasing trend from group Ⅰto group Ⅲand then an opposite trend from group Ⅲ to group Ⅳ at different hours of liquid storage.Conclusions:Moringa oleifera leaf extract 500μg/150×10^(6) spermatozoa can be used for liquid semen preservation in Teressa goat at Andaman and Nicobar Islands. 展开更多
关键词 Moringa oleifera SEMEN Teressa goat Andaman and Nicobar islands
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Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review
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作者 Abdel-Aal MAbdel-Karim Mohamed MHamdy Adel A.Surour 《Acta Geochimica》 EI CAS CSCD 2024年第3期588-622,共35页
Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metaga... Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and ages.In addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the ANS.The main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental arcs.Integrated information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic relationships.These include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle wedge.The volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed slightly.Based on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt. 展开更多
关键词 island arc assemblage MAGMATISM Crustal growth NEOPROTEROZOIC Arabian–Nubian Shield Eastern Desert EGYPT
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Spatiotemporal Evolution of Urban Heat Islands and Optimization of Spatial Network Construction in the Central Urban Area of Fuzhou City, China
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作者 ZHAO Qiuyue YU Kunyong +3 位作者 GENG Jianwei LIN Jiqing AI Jingwen LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2024年第5期917-930,共14页
Although accelerated urbanization has led to economic prosperity,it has also resulted in urban heat island effects.Therefore,identifying methods of using limited urban spaces to alleviate heat islands has become an ur... Although accelerated urbanization has led to economic prosperity,it has also resulted in urban heat island effects.Therefore,identifying methods of using limited urban spaces to alleviate heat islands has become an urgent issue.In this study,we assessed the spatiotemporal evolution of urban heat islands within the central urban area of Fuzhou City,China from 2010 to 2019.This assessment was based on a morphological spatial pattern analysis(MSPA)model and an urban thermal environment spatial network constructed us-ing the minimum cumulative resistance(MCR)model.Optimization measures for the spatial network were proposed to provide a theor-etical basis for alleviating urban heat islands.The results show that the heat island area within the study area gradually increased while that of urban cold island area gradually decreased.The core area was the largest of the urban heat island patch landscape elements with a significant impact on other landscape elements,and represented an important factor underlying urban heat island network stability.The thermal environment network revealed a total of 197 thermal environment corridors and 93 heat island sources.These locations were then optimized according to the current land use,which maximized the potential of 1599.83 ha.Optimization based on current land use led to an increase in climate resilience,with effective measures showing reduction in thermal environment spatial network structure and function,contributing to the mitigation of urban heat island.These findings support the use of current land use patterns during urban heat island mitigation measure planning,thus providing an important reference basis for alleviating urban heat island effects. 展开更多
关键词 urban heat island spatiotemporal analysis circuit theory post optimization evaluation climate mitigation Fuzhou City China
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A Hidden Gem Called Changdao Breathtaking scenery and the islanders’commitment to sustainable living
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作者 Hendy Yuniarto 《China Report ASEAN》 2024年第1期60-61,共2页
Changdao Island,a hidden gem in east China’s Shandong Province,features breathtaking nature.As the sun cuddles the horizon,the island’s azure sky provides a flawless backdrop to an exquisite panorama.Jagged cliffs c... Changdao Island,a hidden gem in east China’s Shandong Province,features breathtaking nature.As the sun cuddles the horizon,the island’s azure sky provides a flawless backdrop to an exquisite panorama.Jagged cliffs carved by centuries of endless waves stand guard along the shoreline,their rocky silhouettes seemingly frozen in time,summoning ancient majesty.Against this dramatic backdrop,flocks of seagulls take flight,their ivory wings catching the golden hues of the sun,creating an enchanting ballet in the sky.The air is filled with the gentle cries of these graceful birds,enhancing the island’s serenity.This harmonious blend of nature’s elements,from the sapphire sea to the towering cliffs and the mesmerizing flight of seagulls,makes Changdao Island an artistic masterpiece painted by the hand of mother nature herself. 展开更多
关键词 island island GENTLE
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The variation in basal channels and basal melt rates of Pine Island Ice Shelf
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作者 Mingliang Liu Zemin Wang +2 位作者 Baojun Zhang Xiangyu Song Jiachun An 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第1期22-34,共13页
In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly... In recent years,there has been a significant acceleration in the thinning,calving and retreat of the Pine Island Ice Shelf(PIIS).The basal channels,results of enhanced basal melting,have the potential to significantly impact the stability of the PIIS.In this study,we used a variety of remote sensing data,including Landsat,REMA DEM,ICESat-1 and ICESat-2 satellite altimetry observations,and Ice Bridge airborne measurements,to study the spatiotemporal changes in the basal channels from 2003 to 2020 and basal melt rate from 2010 to 2017 of the PIIS under the Eulerian framework.We found that the basal channels are highly developed in the PIIS,with a total length exceeding 450 km.Most of the basal channels are ocean-sourced or groundingline-sourced basal channels,caused by the rapid melting under the ice shelf or near the groundingline.A raised seabed prevented warm water intrusion into the eastern branch of the PIIS,resulting in a lower basal melt rate in that area.In contrast,a deepsea trough facilitates warm seawater into the mainstream and the western branch of the PIIS,resulting in a higher basal melt rate in the main-stream,and the surface elevation changes above the basal channels of the mainstream and western branch are more significant.The El Ni?o event in 2015–2016 possibly slowed down the basal melting of the PIIS by modulating wind field,surface sea temperature and depth seawater temperature.Ocean and atmospheric changes were driven by El Ni?o,which can further explain and confirm the changes in the basal melting of the PIIS. 展开更多
关键词 Pine island Ice Shelf basal channel basal melt rate digital elevation models(DEMs) satellite altimetry
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Fish Assemblage and Abundance Distribution in Nanji Islands Marine Nature Reserve in Relation to Season Change
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作者 Cheikh Sarr Cungen Yu +2 位作者 Ousmane Ndiaye Hamet Diadhiou Ngor Ndour 《Journal of Agricultural Chemistry and Environment》 2024年第1期13-32,共20页
The fishing survey station located in the warm waters of the East China Sea is one of the abundant fishery resources of waters;with a large number of economic fish breeding grounds and economic juvenile feeding ground... The fishing survey station located in the warm waters of the East China Sea is one of the abundant fishery resources of waters;with a large number of economic fish breeding grounds and economic juvenile feeding grounds. Several fish species according to this bottom trawl survey results which appear in the annual survey from winter to autumn give us a total of 58 species, which have appeared throughout the year. But the vast majority of species appears only in certain seasons, according to the sea fish survey and based on seasonal migratory species or species mainly small endemic species. The survey of fish is tropical and subtropical warm water species and warm temperate species, and the history of the area has several types of 397 different species. There are many reasons, in addition to recent years, human disturbance and adverse consequences of environmental changes brought about, but also with the relevant sampling methods and sampler time, the survey sampled only trawl based, from Ping yang Ocean and Fisheries Bureau, the waters are still other jobs method net, gill nets, fishing industry, etc. Survey results show that the type of fish in the summer (58 species) > spring (55 species) > winter (51 species) > autumn (42 species). The type of season was among spring to summer rose, summer to autumn decline. The survey found that in the reef area of the Nanji Islands, no one species of fish is the dominant species throughout the year (according to the dominant species, each species is dominant only in one season). From the dominant species turnover accounting for the four seasons, in winter it has 53.72% of the total biomass or annual biomass, spring it has 41.53% of the overall biomass, summer it has 31.85% and autumn it has 38.56% of total biomass. Visible, seasonal succession of dominant species of fish phenomenon is very obvious, especially in the spring and winter, summer transfers dominate species at this stage show the greatest change, but winter, the transfer of this dominant species changes in minimal. Seasonal changes from biomass and the average annual marine fish survey biomass were 4832.25 g/h. From different seasons, the average biomass in winter (10779.88 g/h) > of the average biomass in spring (3624.1 g/hour) > of the mean biomass in autumn (3158 g/h) > the average Biomass in summer (1767 g/h). All of them show significant seasonal variation of the biomass, in winter and spring, the biomass is generally not high, but significantly higher than in the summer and autumn seasons. Each season, around the coast of southern Zhejiang, is less than the biomass and other catches off, which involves investigating sea location, size range, and the survey ship different network related tools. Another change from the area of biomass, some studies found that the survey of four-season fish of waters above the biological capacity of several kilograms only in some stations, namely stations and the highest biomass in summer appeared in stations 3, 7 and 11. In autumn the highest biomass appeared in stations 3, 6, 20 and 23. 展开更多
关键词 Nanji islands Species Composition Abundance Distribution SEASONS
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