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Zoning Evaluation of Hourly Precipitation in High-resolution Regional Numerical Models over Hainan Island
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作者 冯箫 吴俞 +1 位作者 杨薇 李勋 《Journal of Tropical Meteorology》 SCIE 2023年第4期460-472,共13页
This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequen... This study assesses the performance of three high-resolution regional numerical models in predicting hourly rainfall over Hainan Island from April to October for the years from 2020 to 2022.The rainfall amount,frequency,intensity,duration,and diurnal cycle are examined through zoning evaluation.The results show that the China Meteor-ological Administration Guangdong Rapid Update Assimilation Numerical Forecast System(CMA-GD)tends to forecast a higher occurrence of light precipitation.It underestimates the late afternoon precipitation and the occurrence of short-duration events.The China Meteorological Administration Shanghai Numerical Forecast Model System(CMA-SH9)reproduces excessive precipitation at a higher frequency and intensity throughout the island.It overestimates rainfall during the late afternoon and midnight periods.The simulated most frequent peak times of rainfall in CMA-SH9 are 0-1 hour deviations from the observed data.The China Meteorological Administration Mesoscale Weather Numerical Forecasting System(CMA-MESO)displays a similar pattern to rainfall observations but fails to replicate reasonable structure and diurnal variation of frequency-intensity.It underestimates the occurrence of long-duration events and overestimates related rainfall amounts from midnight to early morning.Notably,significant discrepancies are observed in the predictions of the three models for areas with complex terrain,such as the central,southeastern,and southwestern regions of Hainan Island. 展开更多
关键词 hainan island hourly precipitation regional numerical model zoning evaluation
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Granite thermal reservoirs in Lingshui area of Hainan Island and their significance to geothermal resources,China
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作者 Xiaorui Yun Ying Zhang +2 位作者 Dingyong Liang Yanming Qu Haifeng Chen 《Energy Geoscience》 2023年第4期159-170,共12页
Hainan Island located at the southernmost tip of the continental crust of the South China Plate,has high terrestrial heat-flow values,widely-distributed hot springs,and rich geothermal resources.Intensified researches... Hainan Island located at the southernmost tip of the continental crust of the South China Plate,has high terrestrial heat-flow values,widely-distributed hot springs,and rich geothermal resources.Intensified researches on the origin and potentials of geothermal resources can promote Hainan Island's development into a clean energy island.To determine the geological conditions for the formation of geothermal resources in southern Hainan Island,we collected core samples of granites from the Baocheng batholith in southern Hainan Island and conducted systematic analysis in respect of petrology,geochronology,geochemistry,and petrophysical property.The results of this study are as follows.The Baocheng batholith in the southern Hainan Island has a crystallization age of 98.42±0.56 Ma,making it the product of magmatism in the early stage of the Late Cretaceous.It mainly consists of high-K calc-alkaline granites,which were intruded by intermediate-to-mafic veins.The Baocheng batholith has a high radioactive heat generation rate of 2.712-6.843μW/m^(3),with an average of 3.846μW/m^(3),a radioactive heat-flow value of 30.768 μW/m^(2)and a heat-flow contribution rate of 38.95%-43.95%.As shown by the results of their thermophysical property analysis,the granites have high thermal conductivity and can serve as highquality geothermal reservoirs.In combination with previous geological and geophysical data,the geothermal model of the Lingshui area was established in this study.The deep structure indicates the presence of high-conductivity and low-resistivity layers in the basement of the Baocheng batholith.It can be inferred thereby that asthenospheric upwelling may occur and that there exist two magma vents at depth in the batholith.Therefore,magmatic heat at depth and granites with high radioactive heat generation rate serve as the main heat sources in the Lingshui area. 展开更多
关键词 hainan island Geothermal energy Baocheng batholith GRANITE Radioactive heat flow Thermal conductivity
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Increasing Anthropogenic Mercury Pollution over the Last 200 Years Revealed by Lagoonal Sediments from Hainan Island,South China
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作者 LI Yanting XUE Jibin +2 位作者 CHEN Jingqiang LU Yi MA Xinlu 《Chinese Geographical Science》 SCIE CSCD 2023年第6期1127-1140,共14页
The toxic heavy metal mercury(Hg)has significantly enhanced the global Hg cycle influenced by human activities over the last century.In this study,we presented a high-resolution Hg deposition history between∼1780 and... The toxic heavy metal mercury(Hg)has significantly enhanced the global Hg cycle influenced by human activities over the last century.In this study,we presented a high-resolution Hg deposition history between∼1780 and 2015 AD in a sediment core from Xincun Lagoon,located in the southeastern Hainan Island,South China,and analyzed it in conjunction with geochemical elements,grain-size distribution,organic matter,and HYSPLIT backward trajectory simulation.The objective was to investigate the influencing factors affecting historical Hg deposition in relatively remote regions and assess the extent of the effects of natural background and human activities.The results showed that the Hg in the sediment was deposited primarily through atmospheric deposition,which was closely related to regional and even global human activities.Anthropogenic Hg contamination increased gradually from the 1830s to 1850s,possibly due to Hg emissions from Opium Wars I and II occurring in southeastern China.High broad peaks of anthropogenic Hg were observed during the 1910s to 1950s and in the 1980s,likely associated with the two world wars and modern Chinese wars.In addition,a further sharp increase in anthropogenic Hg from the mid-1970s to the present occurred,likely originating from the intense industrial activities in China triggered by the reform and opening-up policy of China in 1978 and some countries in Southeast Asia. 展开更多
关键词 Mercury deposition pollution history anthropogenic impact Xincun Lagoon hainan China
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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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Potential mosquito-associated melioidosis and analysis of sample processing results in Hainan, China, 2023
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作者 Xun Kang Shaowen Cheng +2 位作者 Rui Zheng Hengjie Zhu Qianfeng Xia 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期235-236,共2页
Burkholderia(B.)pseudomallei is a Gram-negative bacterium causing melioidosis,a tropical infection that is being recognized as a growing public health problem[1].Melioidosis,with mortality rates ranging from under 10%... Burkholderia(B.)pseudomallei is a Gram-negative bacterium causing melioidosis,a tropical infection that is being recognized as a growing public health problem[1].Melioidosis,with mortality rates ranging from under 10%to 40%,is a significant concern in Southeast Asia,Australia,and beyond[2].The underdiagnosis,particularly in rural areas,emphasizes the need for improved awareness,surveillance,and management,potentially classifying melioidosis as a neglected tropical disease[3]. 展开更多
关键词 TROPICAL hainan NEGLECTED
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Hainan Leads Reform and Opening-Up with FTP
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作者 ZHOU FAYUAN LI HONGWEI ZHAO QINGGUO 《China Today》 2024年第8期29-31,共3页
Hainan progresses with its mandate to build a free trade port(FTP)with Chinese characteristics for global benefit.FOR Hainan Province in south China,2024 is a crucial year for promoting independent customs operations ... Hainan progresses with its mandate to build a free trade port(FTP)with Chinese characteristics for global benefit.FOR Hainan Province in south China,2024 is a crucial year for promoting independent customs operations throughout the whole island.It is also the sixth year into the island province’s gradual exploration into FTP construction with Chinese characteristics. 展开更多
关键词 hainan island characteristics.
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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China 被引量:1
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model hainan Tropical Rainforest National Park(HTRNP)of China
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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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Application of fecal immunochemical test in colorectal cancer screening:A community-based,cross-sectional study in averagerisk individuals in Hainan
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作者 Fan Zeng Da-Ya Zhang +12 位作者 Shi-Ju Chen Run-Xiang Chen Chen Chen Shi-Mei Huang Da Li Xiao-Dong Zhang Jia-Jia Chen Cui-Yi Mo Lei Gao Jun-Tao Zeng Jian-Xin Xiong Zhai Chen Fei-Hu Bai 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第8期3445-3456,共12页
BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage diagnoses.This highlights the significance of early detection and prevention measures to enhance s... BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage diagnoses.This highlights the significance of early detection and prevention measures to enhance survival rates.Fecal immunochemical testing(FIT)is a globally recommended CRC screening method;however,limited research has been conducted on its application in Hainan.AIM To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan,while also examining the risk factors associated with positive FIT results.METHODS This population-based cross-sectional study implemented FIT screening for CRC in 2000 asymptomatic participants aged 40-75 years from five cities and 21 community health centers in Hainan Province.The study was conducted from August 2022 to April 2023,employing a stratified sampling method to select participants.Individuals with positive FIT results subsequently underwent colonoscopy.Positive predictive values for confirmed CRC and advanced adenoma were calculated,and the relationship between relevant variables and positive FIT results was analyzed usingχ2 tests and multivariate logistic regression.RESULTS A total of 1788 participants completed the FIT screening,with a median age of 57 years(interquartile range:40-75).Among them,503(28.1%)were males,and 1285(71.9%)were females,resulting in an 89.4%compliance rate for FIT screening.The overall positivity rate of FIT was 4.4%[79 out of 1788;95%confidence interval(CI):3%-5%].The specific positivity rates for Haikou,Sanya,Orient City,Qionghai City,and Wuzhishan City were 9.6%(45 of 468;95%CI:8%-11%),1.3%(6 of 445;95%CI:0.1%-3.1%),2.7%(8 of 293;95%CI:1.2%-4.3%),3.3%(9 of 276;95%CI:1.0%-6.3%),and 4.2%(11 of 406;95%CI:1.2%-7.3%),respectively.Significant associations were found between age,dietary habits,and positive FIT results.Out of the 79 participants with positive FIT results,55 underwent colonoscopy,demonstrating an 82.2%compliance rate.Among them,10 had a clean gastrointestinal tract,43 had polyps or adenomas,and 2 were confirmed to have CRC,yielding a positive predictive value of 3.6%(95%CI:0.9%-4.2%).Among the 43 participants with polyps or adenomas,8 were diagnosed with advanced adenomas,resulting in an advanced adenoma rate of 14.5%(95%CI:10.1%-17.7%).CONCLUSION In the Hainan region,FIT screening for CRC among asymptomatic individuals at average risk is feasible and wellreceived. 展开更多
关键词 Fecal immunochemical test Colorectal cancer ADENOMA Screening hainan Province
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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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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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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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