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Paleogene transgression process and environmental evolution in the deepwater area of the Baiyun Depression in the northern South China Sea
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作者 Peijun Qiao Yuchi Cui +2 位作者 Qiong Ma Qiang Yu Lei Shao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期15-24,共10页
Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal an... Multiple borehole samples are collected from the Baiyun Depression in deep-water area of the northern South China Sea(SCS)in an effort to reconstruct transgression processes during the Paleogene based on palynalgal analysis.This study indicates that the Baiyun Depression generated a large group of palynopore assemblages and fluvial/lacustrine-related algae during the early and middle Eocene when the Wenchang Formation was deposited.The entire depression was dominated by fluvial and lacustrine facies before transgression.Its eastern and southeastern sags transitioned to shallow marine environment by generating a large abundance of marine dinoflagellates during the Enping deposition of the late Eocene.Meanwhile,the southern uplift zone simply yielded fluvial/lacustrine-related palynopores and algae,and was dominated by the fluvial and lacustrine environment during the early stage of the Enping Formation,prior to shifting into transitional setting in the later period.Northwestern sags remained extensive fluvial and delta facies without existence of marine dinoflagellates.It was until the depositional stage of the Zhuhai Formation(Oligocene)that the overall depression was strongly impacted from transgression process.Both eastern and southeastern sags were mainly under deep marine setting on a continental slope while northwestern and southern areas developed transitional facies.Although distribution and accumulation patterns varied greatly among sub-sags,the overall Baiyun Depression was characterized by widespread development of marine dinoflagellates.It should be noted that the northwestern sag also partly generated large-scale river delta deposits.Due to the eustatic rise and change of SCS spreading axis,the overall Baiyun Depression was mostly influenced by the deep marine environment on a continental slope during the early Miocene.Both northwestern sag and southern uplift zone were found plentiful marine dinoflagellates.In summary,transgression initiated from the eastern and southeastern Baiyun Depression before subsequently progressing into the farther west.Evolution of transgression process is also greatly consistent with the gradual westward expansion of the SCS. 展开更多
关键词 South China Sea PALEOGENE TRANSGRESSION sedimentary environment plant ecology
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Paleoenvironmental Evolution and Organic Matter Enrichment Genesis of the Late Turonian Black Shale in the Southern Songliao Basin,NE China
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作者 BAI Jing XU Xingyou +2 位作者 LIU Weibin ZHAO Wenzhi JIANG Hang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1338-1358,共21页
The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentiou... The Upper Cretaceous Qingshankou Formation black shales,deposited in the late Turonian(LTB shales),are the main source rocks of the Songliao Basin.The origins of organic matter enrichment of the shales is a contentious subject fuelling many ongoing debates.This study investigates the genesis of the organic matter-rich shale by using molecular geochemistry.The LTB shales can be divided into three sections.The SectionⅠshales were deposited in saline,stratified and anoxic water conditions,which are related to seawater incursion events.At least three episodic and periodic seawater incursion events were recognized during SectionⅠshale deposition.The SectionⅡshales deposited in brackish to fresh and deep lake-level conditions with high primary productivity,which are related to lake-level transgression.The SectionⅢshales were deposited under fresh and slightly oxidized water conditions,which are related to lake-level regression.Two organic matter enrichment models for the LTB shales are identified,that is,the seawater incursion model and the maximum lake-level transgression sedimentation model,which act on different shale sections,both playing significant roles in the enrichment of organic matter. 展开更多
关键词 organic matter-rich shale paleoenvironmental evolution enrichment genetics late Turonian CRETACEOUS Songliao Basin
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Central environmental protection inspection and carbon emission reduction: A tripartite evolutionary game model from the perspective of carbon neutrality
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作者 Zhen-Hua Zhang Dan Ling +2 位作者 Qin-Xin Yang Yan-Chao Feng Jing Xiu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2139-2153,共15页
Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction sustainably.This study is conducted using a tripartite evolutionary game model to explore ... Since the carbon neutrality target was proposed,many countries have been facing severe challenges to carbon emission reduction sustainably.This study is conducted using a tripartite evolutionary game model to explore the impact of the central environmental protection inspection(CEPI)on driving carbon emission reduction,and to study what factors influence the strategic choices of each party and how they interact with each other.The research results suggest that local governments and manufacturing enterprises would choose strategies that are beneficial to carbon reduction when CEPI increases.When the initial willingness of all parties increases 20%,50%—80%,the time spent for the whole system to achieve stability decreases from 100%,60%—30%.The evolutionary result of“thorough inspection,regulation implementation,low-carbon management”is the best strategy for the tripartite evolutionary game.Moreover,the smaller the cost and the larger the benefit,the greater the likelihood of the three-party game stability strategy appears.This study has important guiding significance for other developing countries to promote carbon emission reduction by environmental policy. 展开更多
关键词 Central environmental protection INSPECTION Local government Manufacturing enterprise Tripartite evolutionary game Carbon emission reduction
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Spatio-temporal evolution of the coordinated development of high-tech industry agglomeration and resource-environmental carrying capacity in the Yellow River Basin
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作者 LI Yan REN Ai-lian +1 位作者 LI Meng-yu SUN Fan 《Ecological Economy》 2024年第3期219-236,共18页
Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilizatio... Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilization construction.In light of the coupling coordination analysis of the coordination effect of provincial high-tech industry agglomeration and resource carrying capacity in the Yellow River Basin from 2009 to 2021,The evolution of the geographical and temporal pattern of development was investigated using the Moran index and kernel density estimation.The results show that the agglomeration of high-tech industries in the Yellow River Basin presents a development trend of seek improvement in stability,and there is a good coupling and coordination throughout the progression of scientific and technological innovation and the loading capacity of the resource,from the viewpoint of a time series.From the perspective of spatial pattern distribution,the whole basin aims at the lower reaches,accelerates the optimization of digital industry and promotes Yellow River Basin development of superior quality through innovation support and increase of input,and based on policy guidance. 展开更多
关键词 Yellow River Basin high-tech industrial agglomeration resource carrying capacity coupling coordination space-time evolution
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Highly mass activity electrocatalysts with ultralow Pt loading on carbon black for hydrogen evolution reaction
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作者 Shaorou Ke Yajing Zhao +6 位作者 Xin Min Yanghong Li Ruiyu Mi Yangai Liu Xiaowen Wu Minghao Fang Zhaohui Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期182-190,共9页
Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this s... Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts. 展开更多
关键词 hydrogen evolution reaction ultralow platinum in-situ synthesis ULTRASOUND
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Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis
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作者 Jie Wang Wei Wang +4 位作者 Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期58-69,共12页
The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the micro... The utilization of iron coke provides a green pathway for low-carbon ironmaking.To uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was investigated.Furthermore,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric method.The findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and interconnect.This provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron coke.Accelerating the heating rate in non-isothermal gasification can enhance the reactivity of iron coke.The metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon atoms.The kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore structure.Moreover,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%. 展开更多
关键词 low-carbon ironmaking iron coke GASIFICATION structural evolution kinetic model
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Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
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作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction Supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization
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作者 Xing Wang Wei Pi +3 位作者 Sheng Hu Haifeng Bao Na Yao Wei Luo 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期281-292,共12页
Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal int... Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in AEMWEs.Herein,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this work.Experimental and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER performance.More critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h. 展开更多
关键词 NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer
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Establishment of human cerebral organoid systems to model early neural development and assess the central neurotoxicity of environmental toxins
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作者 Daiyu Hu Yuanqing Cao +6 位作者 Chenglin Cai Guangming Wang Min Zhou Luying Peng Yantao Fan Qiong Lai Zhengliang Gao 《Neural Regeneration Research》 SCIE CAS 2025年第1期242-252,共11页
Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-li... Human brain development is a complex process,and animal models often have significant limitations.To address this,researchers have developed pluripotent stem cell-derived three-dimensional structures,known as brain-like organoids,to more accurately model early human brain development and disease.To enable more consistent and intuitive reproduction of early brain development,in this study,we incorporated forebrain organoid culture technology into the traditional unguided method of brain organoid culture.This involved embedding organoids in matrigel for only 7 days during the rapid expansion phase of the neural epithelium and then removing them from the matrigel for further cultivation,resulting in a new type of human brain organoid system.This cerebral organoid system replicated the temporospatial characteristics of early human brain development,including neuroepithelium derivation,neural progenitor cell production and maintenance,neuron differentiation and migration,and cortical layer patterning and formation,providing more consistent and reproducible organoids for developmental modeling and toxicology testing.As a proof of concept,we applied the heavy metal cadmium to this newly improved organoid system to test whether it could be used to evaluate the neurotoxicity of environmental toxins.Brain organoids exposed to cadmium for 7 or 14 days manifested severe damage and abnormalities in their neurodevelopmental patterns,including bursts of cortical cell death and premature differentiation.Cadmium exposure caused progressive depletion of neural progenitor cells and loss of organoid integrity,accompanied by compensatory cell proliferation at ectopic locations.The convenience,flexibility,and controllability of this newly developed organoid platform make it a powerful and affordable alternative to animal models for use in neurodevelopmental,neurological,and neurotoxicological studies. 展开更多
关键词 cadmium cell death cell proliferation cortical development environmental toxins neural progenitor cells NEUROGENESIS NEUROTOXICOLOGY ORGANOIDS stem cells
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ENVIRONMENTAL EVOLUTION OF ORDOS DESERT IN CHINA SINCE 1.1MA B. P. AS INDICATED BY YULIN STRATIGRAPHICAL SECTION AND ITS GRAIN-SIZE ANALYSIS RESULTS 被引量:4
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作者 LIBao-sheng GAOShang-yu +1 位作者 DONGGuang-rong JINHe-ling 《Chinese Geographical Science》 SCIE CSCD 2005年第1期34-41,共8页
Yulin section is a typical sedimentary record for reflecting the environmental evolution of Ordos Desert, China in the past 1.1Ma. By analyzing its sequence and grain-size composition some views have been put forward ... Yulin section is a typical sedimentary record for reflecting the environmental evolution of Ordos Desert, China in the past 1.1Ma. By analyzing its sequence and grain-size composition some views have been put forward in this paper as follows. The layers of sand, loess and palaeosol in Yulin section were respectively formed by wind and the pedogenesis on parent material of the sand and loess. Since 1.1Ma B. P., Ordos Desert has alternately experienced 11 stages of shifting dunes under extreme cold-dry climatic environment, 7 stages of fixed and semi-fixed dunes and 8 stages of dust (loess) under cold-dry climatic condition; and the pedogenesis environment under 15 times of warm-humid climate and 3 times of temperate-humid climate (brownish-drab soils and black soils formed respectively). The aeolian sand had already existed in Ordos Desert at latest by 1.1Ma B. P., and from that time on it has undergone a series of alternative processes of shifting sands, fixed and semi-fixed dunes, loess and soils. Ordos Desert has been situated in the transitional belt of the Mongolian High Pressure and margin of the southeast summer monsoon since 1.1Ma B. P., and influenced repeatedly by migration of the lithofacies belts of shifting sands, fixed and semi-fixed dunes, loess and soils, which have been caused by the climatic fluctuations of glacial and interglacial periods. 展开更多
关键词 Ordos Desert Yulin stratigraphical section past 1.1Ma grain-sizecomposition environment evolution
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Environmental evolution in the salt-water intrusion area south of Laizhou Bay since late Pleistocene 被引量:4
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作者 ZHANG Zulu LIU Enfeng +1 位作者 ZHANG Yan XIN Liangjie 《Journal of Geographical Sciences》 SCIE CSCD 2008年第1期37-45,共9页
The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses o... The south coastal plain of Laizhou Bay is one of the typical salt-water intrusion areas in China, the occurrence and development of which was closely related with the palaeoenvironment evolution. Systematic analyses of pollen, foraminifera and grain size composition based on ^14C and luminescence dating from two sediment cores were performed for the purpose of understanding the salt-water intrusion in the coastal plain of Laizhou Bay from the perspective of environmental evolution since late Pleistocene. It could be classified into seven evolution stages since 120 kaBP: 120-85 kaBP was a transition period from cold to warm; 85-76 kaBP was a period with warm and wet climate having swamp lakes developed in the lower reaches of the Weihe River, south coastal plain of Laizhou Bay; 76-50 kaBP was characterized by grassland vegetation and coarse sediments in terrestrial environment, which was the early stage of Dali Ice-Age; 50-24 kaBP was a period with alternate sea deposition in the south coastal plain of Laizhou Bay; 24-10 kaBP was the late stage of Dali Ice-Age with coldest period of Quaternary, the south coastal plain of Laizhou Bay was dry grassland and loess deposition environment; 10-4 kaBP was another warm and wet climate period, sea level was high and regressed at 4 kaBP; and has been the modern sedimentary environment since 4 kaBP. Among the three warm stages, including 85-76 kaBP, 50-24 kaBP and 10-4 kaBP, corresponded to late Yangkou, Guangrao and Kenli seawater transgression respectively. The duration of the latter one in south coastal plain of Laizhou Bay was longer than that in west coast of Bohai Sea and east coast of Laizhou Bay. The three periods of seawater transgression formed the foundation of salt-water intrusion in this area. 展开更多
关键词 environmental evolution salt-water intrusion late Pleistocene south coastal plain of Laizhou Bay China
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Formation and water environmental evolution of the Nansihu Lake 被引量:1
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作者 ZHANGZulu SHENJi +2 位作者 LIUEnfeng SUNQingyi JIANGLuguang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期241-249,共9页
Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-co... Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-core and Ws-core in Nansihu Lake, the authors analyze the formation cause of the Nansihu Lake and its water environmental changes. Historical documents are also analyzed here in order to reach the conclusion. Researches indicate that the Nansihu Lake came into being about 2500 aBP and its evolution succession can be divided into four stages. In this evolution process, several scattered lakes merge into one large lake in the east of China. This process is distinctively affected by the overflow of the Yellow River, the excavation of the Grand Canal and other human activities. 展开更多
关键词 Nansihu Lake lake sediment study water environment evolution migration and overflow of the Yellow River excavation of the Grand Canal CLC number:X144
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The Environmental Landscape Evolution of the Loess under the Background of Global Climate Change 被引量:1
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作者 ZHAO Kun-kun1,ZHOU Bao-tong1,WANG Xiao-zhe2,LIU Jing-cai1,FENG Xiao-hong1,CHEN Chun-bo1 1.Department of Geographical Sciences,Southwest University,Chongqing 400715,China 2.Travelling and Environment College,Shaanxi Normal University,Xi’an 710043,China 《Meteorological and Environmental Research》 CAS 2011年第5期28-30,共3页
[Objective] The aim was to study the environment evolution of Shanbei Loess landscape under the background of global climate changes.[Method] The annual and monthly temperature and precipitation in Yulin area in north... [Objective] The aim was to study the environment evolution of Shanbei Loess landscape under the background of global climate changes.[Method] The annual and monthly temperature and precipitation in Yulin area in north Shaanxi from 1952 to 2009 were selected,and by dint of linear regression and M-K mutation,the Loess land form evolution under the global climate change was studied.[Result] The temperature in Yulin area showed increasing tendency from 1952 to 2009 at a speed of 0.287℃/10 a.The year 1994 was a year of mutation of temperature;precipitation decreased at speed of 8.262 mm/10 a and the precipitation fluctuated largely in 1960s,and stably in 1970s,1980s and 1990s.It showed drying tendency.The climate in north Shanxi was becoming warmer.The extreme dry and flood incident,especially the rising drought occurrence frequency had more serious endangerment to the fragile ecological environment.The ' warmer drought' of climate worsened the environment in north Shaanxi,with temperature rising and worsening drought;reduction of precipitation made the wind and sand more active;the frequency of sandstorm increased;desertification of land furthered;the water and soil losses in Loess was serious and might led to degradation of land in north Shaanxi.[Conclusion] The study provided theoretical basis for the ecological and environmental construction in the region. 展开更多
关键词 Climate changes Loess landscape Environment evolution North Shaanxi China
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Phases of Environmental Evolution Indicated by Primary Chemical Elements and Paleontological Records in the Upper Pleistocene-Holocene Series for the Salawusu River Valley,China 被引量:17
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作者 LI Baosheng WEN Xiaohao +5 位作者 QIU Shifan David Dian ZHANG DU Shuhuan CHEN Deniu OU Xianjiao NIU Dongfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第4期555-565,共11页
Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section ... Studies of lithology, sedimentary facies and the distribution regularity of SiO2 and Al2O3 contents and Al2O3/SiO2 ratio allow us to divide the Upper Pleistocene-Holocene Series represented by the MUanggouwan section in China's Salawnsu River valley into six segments: MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6. The boundary ages for MGS1 (the Dishaogouwan and Dagouwan Formations), MGS2 (the upper Chengchuan Formation), MGS3 (the middle Chengchuan Formation), MGS4 (the lower Chengchuan Formation), MGS5 (most strata of the Salawusu Formation) and MGS6 (the bottom of the Salawusu Formation and the top of the Lishi Formation) correspond to those of MIS1, MIS2, MIS3, MIS4, MISS and MIS6, respectively, from deep sea sediments or continental glaciers. MGS5 can be subdivided into five subsegments (MGS5a, MGS5b, MGS5c, MGS5d and MGS5e) and the boundary ages of these subsegments correspond to those of MISSa, MISSb, MIS5c, MIS5d and MIS5e, respectively. Based on the paleoenvironment and paleoecology indicated by the primary chemical elements, fossil vertebrates, mollusks and pollen grains, we hypothesize that MGS1, MGS2, MGS3, MGS4, MGS5 and MGS6 and the subsegments of MGS5 match the corresponding stages for oxygen isotopes in the deep sea sediments and continental glaciers, and the substages of MIS5 in terms of climatic characters, further explaining the phenomena that determined the formation of the late Quaternary strata and the paleontology of the Salawusu River valley. These phenomena relate to fluctuations in the global climate (and particularly in the East Asian monsoon) during the glacial and interglacial periods. 展开更多
关键词 Salawusu River valley Upper Pleistocene-Holocene Series primary chemical elements phases of evolution paleontological records
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Diagenetic Evolution and Formation Mechanisms of High-Quality Reservoirs under Multiple Diagenetic Environmental Constraints:An Example from the Paleogene Beach-Bar Sandstone Reservoirs in the Dongying Depression,Bohai Bay Basin 被引量:5
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作者 WANG Jian CAO Yingchang +1 位作者 SONG Guoqi LIU Huimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第1期232-248,共17页
The diagenetic environment, diagenetic responses, diagenetic transformation model and formation mechanisms of high-quality reservoirs(beach-bar sandstones of the Paleogene fourth member) in the Dongying depression w... The diagenetic environment, diagenetic responses, diagenetic transformation model and formation mechanisms of high-quality reservoirs(beach-bar sandstones of the Paleogene fourth member) in the Dongying depression were studied through the analysis of fluid inclusions, thin section and burial evolution history. The diagenetic fluids of the beach-bar sandstone reservoirs evolved from early high salinity and weak alkalinity to low salinity and strong acidity, late high salinity and strong alkalinity and late low salinity and acidity, which were accompanied by two stages of oil and gas filling. The fluids at the margins of the sandbodies were continuously highly saline and strongly alkaline. The western(eastern) reservoirs experienced early open(closed), middle open, and late closed diagenetic environments during their burial history. The flow pattern was characterized by upwelling during the majority of the diagenesis(in the east, a non-circulating pattern transitioned into an upwelling current). Due to the evolution of the diagenetic fluids, the diagenetic sequence of the beach-bar reservoirs was as follows: early weak carbonate cementation; feldspar and carbonate cement dissolution and authigenic quartz cementation; late carbonate and anhydrite cementation, authigenic feldspar cementation, and late quartz dissolution; and late carbonate cementation, feldspar dissolution, and authigenic quartz cementation. The diagenetic strength during these stages varied or was absent altogether in different parts of the reservoirs. Due to the closeness of the diagenetic environment and the flow pattern of the diagenetic fluids, the diagenetic products are variably distributed in the sandstones interbedded with mudstones and in the fault blocks. The evolution of multiple alternating alkaline and acidic diagenetic environments controlled the distribution patterns of the reservoir diagenesis and reservoir space, and the reservoir quality index, RQI, increased gradually from the margins to the centers of the sandstones. The closeness of the diagenetic environment and the flow patterns of the diagenetic fluids controlled the differences in the reservoir properties among the fault blocks. With increasing distance from the oil-source faults, the RQI values in the west gradually decreased and in the east initially increased and then decreased. 展开更多
关键词 diagenetic environment DIAGENESIS diagenetic fluids beach-bar high quality reservoir Dongying depression
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Tibetan Plateau:Geodynamics and Environmental Evolution——The cooperative projects based upon the memorandum of CAS and DFG
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作者 YAO Tandong ZHU Liping TAN Ge 《Journal of Geographical Sciences》 SCIE CSCD 2006年第3期371-374,共4页
The Tibetan Plateau (TP) plays a unique role in Earth System Sciences. It represents a key area to understand not only basic geodynamic processes linked with the formation and uplift of mountains and plateaus, but a... The Tibetan Plateau (TP) plays a unique role in Earth System Sciences. It represents a key area to understand not only basic geodynamic processes linked with the formation and uplift of mountains and plateaus, but also the interaction between plateau uplift and environmental changes. Over the last 50 million years the formation of the TP has considerably influenced the global climate and monsoon system. Moreover, the TP proves to be extremely sensitive to present-day global change phenomena. Based upon the foundation of the new Institute of Tibetan Plateau Research (1TP) by the Chinese Academy of Sciences (CAS) and through the Memorandum signed by the CAS and DFG (Deutschen Forschungsgemeinschaft), both CAS and DFG provide opportunities to intensify TP research and to develop coordinated research programs. "The Tibetan Plateau - Geodynamics and Environmental Evolution" consisting of one big projects funded by CAS and five projects funded by DFG that cover the pre- and early-collision history of the TP, the Palaeogene/Neogene uplift and climatic dynamics as well as the Late Quaternary and recent environmental and climatic changes on the TP. The projects are linked through several levels of interactions. 展开更多
关键词 Tibetan Plateau Sino-Germany cooperation GEODYNAMICS environmental evolution
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Genome and population evolution and environmental adaptation of Glyptosternon maculatum on the Qinghai-Tibet Plateau 被引量:2
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作者 Shi-Jun Xiao Zen-Bo Mou +7 位作者 Rui-Bin Yang Ding-Ding Fan Jia-Qi Liu Yu Zou Shi-Lin Zhu Ming Zou Chao-Wei Zhou Hai-Ping Liu 《Zoological Research》 SCIE CAS CSCD 2021年第4期502-513,共12页
Persistent uplift means the Qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments.However,how paleogeographic and paleoclimatic events inf... Persistent uplift means the Qinghai-Tibet Plateau(QTP)is an ideal natural laboratory to investigate genome evolution and adaptation within highland environments.However,how paleogeographic and paleoclimatic events influence the genome and population of endemic fish species remains unclear.Glyptosternon maculatum is an ancient endemic fish found on the QTP and the only critically endangered species in the Sisoridae family.Here,we found that major transposons in the G.maculatum genome showed episodic bursts,consistent with contemporaneous geological and climatic events during the QTP formation.Notably,histone genes showed significant expansion in the G.maculatum genome,which may be mediated by long interspersed nuclear elements(LINE)repetitive element duplications.Population analysis showed that ancestral G.maculatum populations experienced two significant depressions 2.6 million years ago(Mya)and 10000 years ago,exhibiting excellent synchronization with Quaternary glaciation and the Younger Dryas,respectively.Thus,we propose that paleogeography and paleoclimate were dominating driving forces for population dynamics in endemic fish on the QTP.Tectonic movements and temperature fluctuation likely destroyed the habitat and disrupted the drainage connectivity among populations.These factors may have caused severe bottlenecks and limited migration among ancestral G.maculatum populations,resulting in the low genetic diversity and endangered status of the species today. 展开更多
关键词 Qinghai-Tibet Plateau(QTP) Glyptosternon maculatum Genome evolution POPULATION High-altitude adaptation
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RECENT DEVELOPMENT OF RESEARCH ON ENVIRONMENTAL EVOLUTION IN CHINA
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作者 张兰生 《Chinese Geographical Science》 SCIE CSCD 1992年第4期22-31,共10页
Recent achievements of the research on Chinese environmental evolution are brieny summarized in this paper. Following aspects are touched upon: relationship between Chinese environmental evolution and global change, t... Recent achievements of the research on Chinese environmental evolution are brieny summarized in this paper. Following aspects are touched upon: relationship between Chinese environmental evolution and global change, the influence of the swift uplift of the Qinghai-Xizang Plateau, time sequence and the reconstruction of environment in characteristic stages, trend towards dryness in north and northwestern China, sea level change and regional studies. 展开更多
关键词 environmental evolution MONSOON formation UPLIFTING of the QINGHAI-XIZANG PLATEAU
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Quaternary Stratigraphic Division and Paleoenvironmental Evolution Observed from Core LZK1 on Hengsha Island, Shanghai 被引量:1
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作者 KE Xue XIE Jianlei +2 位作者 ZHANG Zongyan ZOU Yarui WANG Guoquan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第4期1167-1177,共11页
The Quaternary sediments in the Yangtze delta are loose and lack precise stratification marks in the lithology. Moreover, due to the limitations of dating methods, it is difficult for Quaternary cores to deliver accur... The Quaternary sediments in the Yangtze delta are loose and lack precise stratification marks in the lithology. Moreover, due to the limitations of dating methods, it is difficult for Quaternary cores to deliver accurate age constraints. Thus, it is a challenge to establish the Quaternary stratigraphic framework. Gravity core LZK1 was drilled on Hengsha Island, Shanghai, in the Yangtze delta, in 2012. The core was terminated at 403.83 m below the local land surface, the uppermost 291.2 m comprising a thick sequence of Quaternary sediments. This study investigated the stratigraphic subdivision and paleoenvironmental change of the Quaternary sediments. From bottom to top, the Quaternary stratigraphic sequence can be subdivided into the lower Pleistocene Anting Formation, Middle Pleistocene Jiading Formation, Upper Pleistocene Chuansha Formation and Nanhui Formation, Holocene Loutang Formation, Shanghai Formation, and Rudong Formation. According to this study, the Hengsha Island area was dominated by a freshwater lacustrine environment during the early Pleistocene, an alternation of shallow lake and shore lake environment during the Middle Pleistocene, a delta plain to lagoonal environment during the early Upper Pleistocene, a fluvial channel to floodplain environment from the LGM(Last Glacial Maximum) to the end of the Upper Pleistocene, and a delta environment during the Holocene. 展开更多
关键词 chronostratigraphic framework paleoenvironmental evolution marine transgression QUATERNARY Yangtze delta
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