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Research on New Media Marketing Strategy of Quzhou Jianglang Mountain Scenic Spot Based on 4R Marketing Theory
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作者 XU Rui-xia YUAN Zhi-qian 《Sino-US English Teaching》 2023年第8期326-333,共8页
With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4... With the increasing popularity of new media,new media marketing plays an increasingly important role in the marketing of tourism scenic spots,bringing a new marketing opportunity to tourism scenic spots.Based on the 4R theory in marketing theory,this paper takes Quzhou Jianglang Mountain as the research object and finds that the following problems exist in the new media marketing of Quzhou Jianglang Mountain:1.The new media users are not closely enough connected;2.the response to the new media market changes is not fast enough;3.the new media marketing relationship interaction is not timely enough;and 4.the return of new media marketing is not ideal.The new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot is proposed from four perspectives:association,reaction,relationship,and return.Finally,the research on the new media marketing strategy of Quzhou Jianglang Mountain Scenic Spot based on the 4R theory is summarized. 展开更多
关键词 4R theory quzhou Jianglang Mountain Scenic Spot new media marketing
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Sedimentological Study of Alluvial Deposits on the Congolese Coast: Highlighting the Erosive Character of the Holocene Wet Climatic Phases
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作者 Hilaire Elenga Nehl Dorland Kobawila +2 位作者 Dieudonne Maurice Malounguila-Nganga Malanda Nimy Edmond Nicaise Giresse Pierre 《Open Journal of Geology》 CAS 2023年第1期1-22,共22页
A granulometric, mineralogical, morphoscopic and exoscopic study and Rock-Eval analysis carried out on samples taken in the Loango Bay and at Kivesso on the Congolese coast have made it possible to highlight the highl... A granulometric, mineralogical, morphoscopic and exoscopic study and Rock-Eval analysis carried out on samples taken in the Loango Bay and at Kivesso on the Congolese coast have made it possible to highlight the highly erosive character of the well-documented wet phases ca 9000 - 3000 years B.P. and ca 320 B.P. in the sub-region. Supported by carbon-14 dating, total organic carbon analyses highlight two major phases of peat deposit emplacement. The first, ca. 7000 years B.P., corresponds to the beginning of the deposition of the yellow formation in the entire Loango Bay;the second, ca. 320 years B.P., is contemporary with the deposition of peat in the Kivesso sector. The granulometric analysis of the sediments shows that they are essentially sandy-clay and very poor in silt, alternating with beds of silty clay sometimes rich in organic matter. These sands have a predominant mode of 0.200 mm and an average varying between 0.150 and 0.300 mm. They constitute the flood phase of the carrier current. They are associated with a population of mode 0.125 mm sometimes 0.050 mm with an average varying between 0.100 mm and 0.126 mm which corresponds to the settling phase. Morphoscopic examination showed several varieties of quartz that argue for a source of supply close to the depositional sites. 展开更多
关键词 holocene PALEOCLIMATES PALEOENVIRONMENTS Loango Bay SEDIMENTOLOGY
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Coral Reef and High Sea Level at Luhuitou, Hainan Island during the Holocene 被引量:2
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作者 黄德银 施祺 张叶春 《Marine Science Bulletin》 CAS 2007年第2期61-70,共10页
According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-st... According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-stands can be identified from the distribution of coral reef ages: 7300 - 6000 cal.aBP, 4800 - 4700 cal.aBP, 4300 - 4200 cal.aBP and 3100 - 2900 cal.aBP. The highest sea level occurred around 7300 - 6700 cal.aBP, and biological-morphological zones took their shape during the stage. The later coral reefs developed in ponds, depressions, and developed outwards on both sides of Luhuitou peninsula. The modern coral reefs are developing in out reef flat and reef-front slope. Moreover, the time of high sea levels in the northern South China Sea recorded by coral reefs in the Luhuitou peninsula can link up with that in other parts of South China Sea. That means the high sea levels in the South China Sea during the Holocene, which are relative to the warming climate, have the global background. 展开更多
关键词 coral reef high sea level Luihuitou holocene
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Essential oil extracted from Quzhou Aurantii Fructus prevents acute liver failure through inhibiting lipopolysaccharide-mediated inflammatory response 被引量:1
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作者 Tian Lan Wen Wang +6 位作者 De-Lian Huang Xi-Xi Zeng Xiao-Xiao Wang Jian Wang Yu-Hua Tong Zhu-Jun Mao Si-Wei Wang 《Natural Products and Bioprospecting》 CSCD 2023年第1期368-381,共14页
Quzhou Aurantii Fructus(QAF)has a long history as a folk medicine and food for the treatment of liver diseases.While our earlier study provided evidence of hepatoprotective properties contained within the flavonoids a... Quzhou Aurantii Fructus(QAF)has a long history as a folk medicine and food for the treatment of liver diseases.While our earlier study provided evidence of hepatoprotective properties contained within the flavonoids and limonins constituents in QAF,the potential preventative effects afforded by essential oil components present within QAF remains enigmatic.In this study,we prepared Quzhou Aurantii Fructus essential oil(QAFEO)and confirmed its anti-inflammatory effects on liver inflammation through experimentation on lipopolysaccharide and D-galactosamine(LPS/D-GalN)induced acute liver failure(ALF)mouse models.Using RNA-sequence(RNA-seq)analysis,we found that QAFEO prevented ALF by systematically blunting the pathways involved in response to LPS and toll-like receptor signaling pathways.QAFEO effectively suppressed the phosphorylation of tank-binding kinase 1(TBK1),TGF-beta activated kinase 1(TAK1),interferon regulatory factor 3(IRF3),and the activation of mitogen activated kinase-like protein(MAPK)and nuclear factor-kappa B(NF-κB)pathways in vivo and in vitro.Importantly,QAFEO substantially reduced myeloid differentiation primary response gene 88(MyD88)-toll-like receptor 4(TLR4)interaction levels.Moreover,8 compounds from QAFEO could directly bind to REAL,TAK1,MyD88,TBK1,and IRF3.Taken together,the results of our study support the notion that QAFEO exerts a hepatoprotective effect through inhibiting LPS-mediated inflammatory response. 展开更多
关键词 quzhou Aurantii Fructus Essential oil Acute liver failure LPS INFLAMMATION
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Research on the Inheritance and Promotion of Quzhou Food Culture Based on New Media
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作者 ZHANG Jiacheng HU Lijun 《Sino-US English Teaching》 2022年第9期326-331,共6页
From the perspective of cultural communication,this paper studies the cultural and economic value of the inheritance and promotion of Quzhou food culture,and analyzes the problems of Quzhou food culture in the process... From the perspective of cultural communication,this paper studies the cultural and economic value of the inheritance and promotion of Quzhou food culture,and analyzes the problems of Quzhou food culture in the process of communication due to the narrow market,insufficient publicity,and lack of clear development ideas.By using the current popular new media means to spread the characteristics and flavors of Quzhou food,it is proposed to inherit and promote Quzhou food culture by creating brand effect of Quzhou food enterprises,setting Quzhou food websites,and shooting food documentaries,which will help publicize Quzhou food culture to the outside world,and thus play a positive role in promoting the local economic development of Quzhou. 展开更多
关键词 new media INHERITANCE PROMOTION quzhou food culture
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Temperature and Precipitation Changes in China During the Holocene 被引量:6
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作者 葛全胜 王绍武 +2 位作者 闻新宇 Caiming SHEN 郝志新 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第6期1024-1036,共13页
We review here proxy records of temperature and precipitation in China during the Holocene, especially the last two millennia. The quality of proxy data, methodology of reconstruction, and uncertainties in reconstruct... We review here proxy records of temperature and precipitation in China during the Holocene, especially the last two millennia. The quality of proxy data, methodology of reconstruction, and uncertainties in reconstruction were emphasized in comparing different temperature and precipitation reconstruction and clarifying temporal and spatial patterns of temperature and precipitation during the Holocene. The Holocene climate was generally warm and wet. The warmest period occurred in 9.6-6.2 cal ka BP, whereas a period of maximum monsoon precipitation started at about 11.0 cal ka BP and lasted until about 8.0-5.0 cal ka BP. There were a series of millennial-scale cold or dry events superimposed on the general trend of climate changes. During past two millennia, a warming trend in the 20th century was clearly detected, but the warming magnitude was smaller than the maximum level of the Medieval Warm Period and the Middle Holocene. Cold conditions occurred over the whole of China during the Little Ice Age (AD 1400-AD 1900), but the warming of the Medieval Warm Period (AD 900-AD 1300) was not distinct in China, especially west China. The spatial pattern of precipitation showed significant regional differences in China, especially east China. The modern warm period has lasted 20 years from 1987 to 2006. Bi-decadal oscillation in precipitation variability was apparent over China during the 20th century. Solar activity and volcanic eruptions both were major forcings governing the climate variability during the last millennium. 展开更多
关键词 proxy data TEMPERATURE PRECIPITATION China holocene
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Millennial-scale evolution of Hunshandake Desert and climate change during the Holocene in Inner Mongolia,northern China 被引量:11
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作者 HeLing Jin Liang Ying Sun Zhong Sun 《Research in Cold and Arid Regions》 2010年第6期505-513,共9页
The Hunshandake Desert is located at the northern edge of the East Asian monsoon region,and its natural environment is sensitive to monsoonal changes.Geologic records suggest that desert evolution corresponding to cli... The Hunshandake Desert is located at the northern edge of the East Asian monsoon region,and its natural environment is sensitive to monsoonal changes.Geologic records suggest that desert evolution corresponding to climate change had experienced several cycles in the Holocene,and the evolutionary process can be distinguished by four dominant stages according to changing trends of the environment and climate.(1) Holocene Ameliorative Period(11.0-8.7 cal ka B.P.),when the desert area gradually shrank following an approaching warm-wet climate and strengthening summer monsoon.(2) Holocene Optimum(8.7-6.0 cal ka B.P.),when the majority of moving sand dunes were stabilized and vegetation coverage quickly expanded in a suitable warm-wet climate and a strong summer monsoon.(3) Holocene Multivariate Period(6.0-3.5 cal ka B.P.),during a low-amplitude desert transformed between moving and stabilized types under alternating functions of cold-dry with warm-wet climate,and winter monsoon with summer monsoon.(4) Holocene Decay Period(since 3.5 cal ka B.P.),when the desert area tended to expand along with a weakened summer monsoon and a dry climate. 展开更多
关键词 Hunshandake Desert desert evolution global climate change holocene
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Sedimentary architecture of the Holocene mud deposit off the southern Shandong Peninsula in the Yellow Sea 被引量:2
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作者 仇建东 刘健 +1 位作者 许红 周良勇 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第1期181-191,共11页
Newly acquired high-resolution seismic profiles reveal a nearshore and an of fshore mud depocenter of f the southern Shandong Peninsula in the Yellow Sea.The nearshore depocenter is distributed in bands along the sout... Newly acquired high-resolution seismic profiles reveal a nearshore and an of fshore mud depocenter of f the southern Shandong Peninsula in the Yellow Sea.The nearshore depocenter is distributed in bands along the south coast of Shandong Peninsula.The of fshore depocenter is part of the distal subaqueous deltaic lobe,which deposited around the southeastern tip of the Shandong Peninsula.Between the two depocenters is a linear depression.The mud deposits directly overlie the postglacial transgressive surface and can be divided into lower and upper units by the Holocene maximum flooding surface.The nearshore and off shore units display different seismic structures.The lower unit of the nearshore deposit exhibits basal onlap,whereas the upper unit is characterized by progradation.The lower and upper units of the off shore deposit display distinct acoustic features.The lower unit has low-angle aggradation with internal reflectors generally dipping seaward and truncated by the Holocene maximum flooding surface,whereas the upper unit is characterized by aggradation and progradation landward rather than seaward.Results of geochemistry analysis of QDZ03 sediments and mineral analysis of WHZK01 sediments suggest that the nearshore deposit and the lower unit of the of fshore deposit are derived from the proximal coastal sediments of the Shandong Peninsula and the Huanghe(Yellow) River sediments.The upper unit of the of fshore deposit is mainly Huanghe River-derived.The lower unit of the mud deposit represents a post-glacial transgressive system tract according to dates of core QDZ03,and the upper unit represents a highstand system tract from middle Holocene to the present.These results will be of great significance to further understanding of the transportation of the Huanghe River sediments into the Yellow Sea and the spatial distribution of the subaqueous delta. 展开更多
关键词 holocene mud deposit Yellow Sea
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Sedimentary Evolution of the Holocene Subaqueous Clinoform off the Southern Shandong Peninsula in the Western South Yellow Sea 被引量:20
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作者 QIU Jiandong LIU Jian +4 位作者 SAITO Yoshiki YANG Zigeng YUE Baojing WANG Hong KONG Xianghuai 《Journal of Ocean University of China》 SCIE CAS 2014年第5期747-760,共14页
Based on the stratigraphic sequence formed since the last glaciation and revealed by 3000 km long high-resolution shallow seismic profiles and the core QDZ03 acquired recently off the southern Shandong Peninsula, we a... Based on the stratigraphic sequence formed since the last glaciation and revealed by 3000 km long high-resolution shallow seismic profiles and the core QDZ03 acquired recently off the southern Shandong Peninsula, we addressed the sedimentary characteristics of a Holocene subaqueous clinoform in this paper. Integrated analyses were made on the core QDZ03, including sedimentary facies, sediment grain sizes, clay minerals, geochemistry, micro paleontology, and AMS 14 C dating. The result indicates that there exists a Holocene subaqueous clinoform, whose bottom boundary generally lies at 15–40 m below the present sea level with its depth contours roughly parallel to the coast and getting deeper seawards. The maximum thickness of the clinoform is up to 22.5 m on the coast side, and the thickness contours generally spread in a banded way along the coastline and becomes thinner towards the sea. At the mouths of some bays along the coast, the clinoform stretches in the shape of a fan and its thickness is evidently larger than that of the surrounding sediments. This clinoform came into being in the early Holocene(about 11.2 cal kyr BP) and can be divided into the lower and upper depositional units(DU 2 and DU 1, respectively). The unit DU 2, being usually less than 3 m in thickness and formed under a low sedimentation rate, is located between the bottom boundary and the Holocene maximum flooding surface(MFS), and represents the sediment of a post-glacial transgressive systems tract; whereas the unit DU 1, the main body of the clinoform, sits on the MFS, belonging to the sediment of a highstand systems tract from middle Holocene(about 7–6 cal kyr BP) to the present. The provenance of the clinoform differs from that of the typical sediments of the Yellow River and can be considered as the results of the joint contribution from both the Yellow River and the proximal coastal sediments of the Shandong Peninsula, as evidenced by the sediment geochemistry of the core. As is controlled mainly by coactions of multiple factors such as the Holocene sea-level changes, sediment supplies and coastal dynamic conditions, the development of the clinoform is genetically related with the synchronous clinoform or subaqueous deltas around the northeastern Shandong Peninsula and in the northern South Yellow Sea in the spatial distribution and sediment provenance, as previously reported, with all of them being formed from the initial stage of the Holocene up to the present. 展开更多
关键词 subaqueous clinoform holocene Yellow Sea Shandong Peninsula Yellow River PROVENANCE sea-level change sedimentary
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Anti-Phase Relationship Between the East Asian Winter Monsoon and Summer Monsoon During the Holocene? 被引量:2
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作者 GE Qian XUE Zuo +2 位作者 YAO Zhigang ZANG Zhengchen CHU Fengyou 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第2期175-183,共9页
The relationship between the East Asian winter monsoon(EAWM) and East Asian summer monsoon(EASM) during the Holocene is complicated and remains controversial.In this study,analysis of grain size and benthic foraminife... The relationship between the East Asian winter monsoon(EAWM) and East Asian summer monsoon(EASM) during the Holocene is complicated and remains controversial.In this study,analysis of grain size and benthic foraminiferal oxygen isotope,as well as accelerator mass spectrometry ^(14)C dating was performed on a sediment core retrieved from the newly revealed muddy deposit on the northern South China Sea continental shelf.The history of the EAWM and EASM were reconstructed for the last 8200 a BP.Further analysis in conjunction with previously published paleo-climate proxies revealed that the relationship between the EAWM and EASM during the Holocene is more complex than a simple and strict anti-phase one-both negative and positive correlations were identified.The EAWM and EASM are negatively correlated around 7500,4800,4200,3200,and 300 a BP(cooling periods),while positively correlated around 7100,3700,and 2100 a BP(warm periods).In particular,both the EAWM and EASM intensified during the three positive correlation periods.However,we also found that the relationship between these two sub-monsoons is anti-phase during the final phase of particularly hot periods like Holocene Optimum and Medieval warm period.The possible impact from variations of solar irradiance on the relationship between the EAWM and EASM was also discussed. 展开更多
关键词 grain size oxygen isotope South China Sea EAST ASIAN winter MONSOON EAST ASIAN summer MONSOON holocene
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Dust source of the Holocene loess-soil and pedogenic environmental changes in the upper Huaihe River 被引量:4
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作者 李新艳 黄春长 +1 位作者 庞奖励 何忠 《Journal of Geographical Sciences》 SCIE CSCD 2009年第1期107-117,共11页
Based on field surveys,soil samples were collected at the YPC site,Yuzhou City,Henan Province for analysis of contents of major and trace elements and their variations with XRF and comparison with the curves of magnet... Based on field surveys,soil samples were collected at the YPC site,Yuzhou City,Henan Province for analysis of contents of major and trace elements and their variations with XRF and comparison with the curves of magnetic susceptibility,pH value distribution,loss on ignition and particle-size distribution.It was concluded that the dust source of loess in the upper reaches of the Huaihe River Basin was different from that in the Loess Plateau.And the Holocene pedogenic environmental changes in the upper reaches of the Huaihe River Basin were revealed. 展开更多
关键词 LOESS PALAEOSOL holocene dust source upper reaches of the Huaihe River China
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Major elements in the Holocene loess-paleosol sequence in the upper reaches of the Weihe River valley,China 被引量:1
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作者 WAN Honglian HUANG Chunchang PANG Jiangli 《Journal of Arid Land》 SCIE CSCD 2016年第2期197-206,共10页
Palaeohydmlogical investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits (SWDs) was found interbedded in the Holocene Ioe... Palaeohydmlogical investigations were carried out in the Guchuan Basin in the upper reaches of the Weihe River valley, China. A set of palaeoflood slackwater deposits (SWDs) was found interbedded in the Holocene Ioess-paleosol sequence at the Guchuanzhen site (GCZ). These palaeoflood SWDs were studied by field observations and laboratory analyses including concentrations of chemical elements and optically stimulated luminescence (OSL) dating. The results showed that the palaeoflood SWDs were the result of the secondary separations of the surface soil and weathered soil layers during the process of water transport and deposition, and without obvious weathering during soil development. These extraordinary flood events were dated back to 3,200-3,000 a B.P. with the OSL method and checked by archaeological dating of the human remains retrieved from the profile. These extraordinary flood events were therefore considered as regional expression of known climatic events and demonstrated the climatic instability in the Holocene. This result is important for understanding the effects of global climate change on the dynamics of river systems. 展开更多
关键词 upper reaches of the Weihe River holocene Ioess-paleosol sequence major elements
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Change in Sediment Provenance Near the Current Estuary of Yellow River Since the Holocene Transgression 被引量:3
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作者 SONG Sheng FENG Xiuli +3 位作者 LI Guogang LIU Xiao XIAO Xiao FENG Li 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期535-544,共10页
Sedimentary sequence and sediment provenance are important factors when it comes to the studies on marine sedimentation. This paper studies grain size distribution, lithological characteristics, major and rare earth e... Sedimentary sequence and sediment provenance are important factors when it comes to the studies on marine sedimentation. This paper studies grain size distribution, lithological characteristics, major and rare earth elemental compositions, micropaleontological features and ^(14)C ages in order to examine sedimentary sequence and sediment provenance of the core BH6 drilled at the mouth of the Yellow River in Bohai Sea. According to the grain size and the micropaleontological compositions, 4 sedimentary units have been identified. Unit 1(0–8.08 mbsf) is of the delta sedimentary facies, Unit 2(8.08–12.08 mbsf) is of the neritic shelf facies, Unit 3(12.08–23.85 mbsf) is of near-estuary beach-tidal facies, and Unit 4(23.85 mbsf–) is of the continental lake facies. The deposits from Unit 1 to Unit 3 have been found to be marine strata formed after the Holocene transgression at about 10 ka BP, while Unit 4 is continental lacustrine deposit formed before 10 ka BP. The provenances of core BH6 sediments show properties of the continental crust and vary in different sedimentary periods. For Unit 4 sediments, the source regions are dispersed while the main provenance is not clear, although the parent rock characteristics of a few samples are similar to the Luanhe River sediments. For Unit 3, sediments at 21.1–23.85 mbsf have been mainly transported from the Liaohe River, while sediments above 21.1 mbsf are mainly from the Yellow River and partially from the Liaohe River. For Unit 2, the sediments have been mainly transported from the Yellow River, with a small amount from other rivers. For Unit 1, the provenance is mainly the Yellow River catchment. These results help in better understanding the evolution of the Yellow River Delta. 展开更多
关键词 Yellow River Estuary holocene transgression rare earth element PROVENANCE
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Linking moisture and near-surface wind with winter temperature to reveal the Holocene climate evolution in arid Xinjiang region of China 被引量:2
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作者 Fuyuan Gao Junhuai Yang +7 位作者 Dunsheng Xia Hao Lu Shuyuan Wang Kaiming Li Zhenqian Wang Zhipeng Wu Jiaxin Zhou Fuxi Shi 《Geoscience Frontiers》 SCIE CAS CSCD 2022年第6期16-29,共14页
An increasing number of palaeo-climatic records have been reported to identify the Holocene climate history in the arid Xinjiang region of northwest China. However, few studies have fully considered the internal linka... An increasing number of palaeo-climatic records have been reported to identify the Holocene climate history in the arid Xinjiang region of northwest China. However, few studies have fully considered the internal linkages within the regional climate system, which may limit our understanding of the forcing mechanisms of Holocene climate change in this region. Here, we systematically consider three major issues of the moisture/precipitation, temperature and near-surface wind relevant to the Holocene climate history of Xinjiang. First, despite there still has debated for the Holocene moisture evolution in this region, more climatic reconstructions from lake sediments, loess, sand-dunes and peats support a long-term regional wetting trend. Second, temperature records from ice cores, peats and stalagmites demonstrate a long-term winter warming trend during the Holocene in middle-to high-latitudes of Asia. Third, recent studies of aeolian sedimentary sequences reveal that the near-surface winds in winter gradually weakened during the Holocene, whereas the winter mid-latitude Westerlies strengthened in the Tienshan Mountains. Based on this evidence, in the arid Xinjiang region we propose an early to middle Holocene relatively cold and dry interval, with strong near-surface winds;and a warmer, wetter interval with weaker near-surface winds in the middle to late Holocene during winter. Additionally,we develop a conceptual model to explain the pattern of Holocene climate changes in this region.From the early to the late Holocene, the increasing atmospheric COcontent and winter insolation,and the shrinking of high-latitude continental ice-sheets, resulted in increasing winter temperatures in middle to high latitudes in the Northern Hemisphere. Subsequently, the increased winter temperature strengthened the winter mid-latitude Westerlies and weakened the Siberian high-pressure system,which caused an increase in winter precipitation and a decrease in near-surface wind strength. This scenario is strongly supported by evidence from geological records, climate simulation results, and modern reanalysis data. Our hypothesis highlights the important contribution of winter temperature in driving the Holocene climatic evolution of the arid Xinjiang region, and it implies that the socio-economic development and water resources security of this region will face serious challenges presented by the increasing winter temperature in the future. 展开更多
关键词 holocene climate change MOISTURE Temperature Near-surface wind strength Siberian high-pressure system Mid-latitude Westerlies
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Environmental anomalies in the northeastern East China Sea during the last 3 000 years:implications for El Nio activity in the Holocene 被引量:2
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作者 常凤鸣 李铁刚 +1 位作者 庄丽华 阎军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第1期190-200,共11页
To reconstruct the productivity changes for the last 10 500 a in the northeastern East China Sea (ECS), biogenic compounds (such as carbonate, organic carbon and opal), marine micropaleontological fossils (plankt... To reconstruct the productivity changes for the last 10 500 a in the northeastern East China Sea (ECS), biogenic compounds (such as carbonate, organic carbon and opal), marine micropaleontological fossils (planktonic foraminifera, benthic foraminifera, radiolarian and silicoflagellate) and the compositional characters of benthic foraminifera fauna analyses were carried out on a sediment core DOC082 obtained from the western slope of Okinawa Trough (29°13.93′N, 128°08.53′E; 1 128 m water depth). The long-term changes of biogenic and micropaleontological proxies display some similarities through the last 10 500 a, which show three different phases: lower values are recorded during the early and middle ttolocene (before about 4 000 a BP), followed by an abrupt and remarkable increase at about 4 000 a BP, the late Holocene (after about 3 000 a BP) is characterized by continuously high values. The multi-proxy data of paleoproductivity and percents of benthic foraminifera genera (Uvigerina and Bulimina) show that during the early and middle Holocene (10 500-4 000 a BP) productivity was relatively low with a sudden and distinct increase at about 4 000 a BP, and the late Holocene (3 400-0 a BP) is marked by significantly higher productivity. Also, the radiolarian-based sea surface temperature (SST) records reveal a distinct decline in SST in the late Holocene after 3 200 a BP, very different from the early and middle Holocene. For the last 3 000 a, the enhanced biological productivity and distinctly lower SST indicate a major change of oceanographic conditions in the northeastern ECS. These marine environmental anomalies are consistent with other paleoclimatic records for the late Holocene in the Chinese continent and its surrounding regions. After analyzing the mechanisms of modern productivity and SST changes in the northeastern ECS, and based on the climatic anomalies in the Chinese continent and variations in the Kuroshio Current during modern El Nino periods, we suggest that the anomalous environmental conditions in the northeastern ECS may imply intensified El Nino activity during the late Holocene. 展开更多
关键词 late holocene environmental anomalies E1 Nino northeastern East China Sea PALEOPRODUCTIVITY sea-surface temperature
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Mangrove forest degradation indicated by mangrove-derived organic matter in the Qinzhou Bay,Guangxi,China,and its response to the Asian monsoon during the Holocene climatic optimum 被引量:1
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作者 MENG Xianwei XIA Peng +1 位作者 LI Zhen LIU Lejun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期95-100,共6页
The response of mangrove ecosystems to the Asian monsoon in the future global warming can be understood by reconstructing the development of mangrove forests during the Holocene climatic optimum(HCO), using proxies ... The response of mangrove ecosystems to the Asian monsoon in the future global warming can be understood by reconstructing the development of mangrove forests during the Holocene climatic optimum(HCO), using proxies preserved in coastal sediments. The total organic matter in sediments of a segmented core, with calibrated age ranges between 5.6 and 7.7 cal. ka BP and corresponding to the HCO, from the Qinzhou Bay in Guangxi, China, is quantitatively partitioned into three end-members according to their sources: mangrove-derived, terrigenous,and marine phytoplanktonic, using a three-end-member model depicted by organic carbon isotope(δ13Corg) and the molar ratio of total organic carbon to total nitrogen(C/N). The percentage of mangrove-derived organic matter(MOM) contribution is used as a proxy for mangrove development. Three visible drops in MOM contribution occurred at ca. 7.3, ca. 6.9, and ca. 6.2 cal. ka BP, respectively, are recognized against a relatively stable and higher MOM contribution level, indicating that three distinct mangrove forest degradations occurred in the Qinzhou Bay during the HCO. The three mangrove forest degradations approximately correspond to the time of the strengthened/weakened Asian winter/summer monsoon. This indicates that even during a period favorable for the mangrove development, such as the HCO, climatic extremes, such as cold and dry events driven by the strengthened/weakened Asian winter/summer monsoon, can trigger the degradation of mangrove forests. 展开更多
关键词 holocene climatic optimum mangrove-derived organic matter degradation of mangrove forests Asian monsoon Qinzhou Bay
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Introduction to the China-Vietnam Cooperation Project: A Comparative Study of the Holocene Sedimentary Evolution of the Yangtze and Red River Deltas
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作者 YIN Ping PHUNG Van Phach +3 位作者 TRAN Dinh Lan DO Huy Cuong BUI Van Vuong DUAN Xiaoyong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第6期1269-1271,共3页
Both China and Vietnam confront the challenges of natural geohazards and environmental changes in their deltas and coastal zones due to rapid urbanization, economic development, and the impacts of global climate chang... Both China and Vietnam confront the challenges of natural geohazards and environmental changes in their deltas and coastal zones due to rapid urbanization, economic development, and the impacts of global climate change. China and Vietnam initiated a comparative study of the Holocene sedimentary evolution of the Yangtze River Delta(YRD) and Red River Delta(RRD) for the period 2015–2018 in order to improve the understanding of the two delta evolution histories in the Holocene. Previous investigative data of the two rivers, onshore delta plains, and offshore subaqueous deltas have been explored and reinterpreted. New data gleaned from boreholes, piston cores, shallow seismic and hydrodynamic sources have been collected from the offshore YRD and the East China Sea inner shelf, and surface sediments and short cores have been collected from the RRD near-shore areas. Six focal areas of the joint project have been defined for comparative studies of the two deltas, including morphological development, sequential stratigraphy, coastline shifting, sedimentary characteristics, sedimentary dynamics, and correlation with anthropogenic global climate change. The results of these study areas are presented herein. The joint project also includes cooperative capacity building; exchanges of young scientists have been organized during the project period, and hands-on training in laboratory geochemical analysis, numerical modeling, and seismic data processing and interpretation have been provided by China and its Vietnamese geoscientist partners. Joint field excursions were organized to the upstream of the Yangtze and Red Rivers in Yunan Province, China, all the way downstream along the Vietnamese portion of the Red River. These joint studies have, over the past three years, improved understanding of the evolutionary history of these two major rivers and their mechanisms of source to sink. Joint project results of these two major deltas are not limited to the geosciences; the cooperative mechanical and operational experiences have been helpful for future cooperation in the field of marine geoscience between China and Vietnam, as well for cooperative activities with other ASEAN member countries. 展开更多
关键词 YANGTZE RIVER DELTA RED RIVER DELTA holocene SEDIMENTARY environment
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Diagenesis and Evolution of the Holocene Coquinite from the Haishan Island,Eastern Guangdong,China
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作者 SUN Jinlong XU Huilong +2 位作者 QIU Xuelin ZHAN Wenhuan LI Yamin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第1期70-80,共11页
The coastal hard rock with a thickness of over 5 m and a distribution area of nearly 200 ha in the Haishan Island, south China, has long drawn researchers' attention. However, there were controversies over its format... The coastal hard rock with a thickness of over 5 m and a distribution area of nearly 200 ha in the Haishan Island, south China, has long drawn researchers' attention. However, there were controversies over its formation and classification, and these controversies in turn lead to the dispute of sea level changes and coastal uplift-subsidence of this area. To investigate its diagenesis and evolution, petrographic analysis, elemental geochemistry, isotopic analysis, and radiocarbon dating were used in the present study. Radiocarbon dating indicates that the deposition of the Haishan Coquinite commenced in the mid Holocene and lasted to -600 a B.P. Petrographic analysis shows that the Haishan Coquinite is cemented by low-Mg calcite, indicating that the cementation occurred in a meteoric environment. The elemental geochemistry and isotopic values demonstrate that the coquinite suffered strong leaching, which was thought to be responsible for the meteoric cementation of the coquinite. According to these results, the diagenesis of the coquinite is revealed: deposition of the Haishan Coquinite commenced in the mid Holocene in a shoal environment, initial cementation occurred and cement may be high-Mg calcite or aragonite; latterly the coquinite exposed to meteoric environment as a result of lowering of relative sea level, and the cement altered to low-Mg, which took the morphologies of bladed calcite rim and equant spar. A four-stage evolution model is proposed: (1) deposition stage, (2) initial cementation, (3) exposure to and cementation in meteoric environment, and (4) erosion stage. The published reports indicate that the hard rock should be designated as coquinite. Based on these studies, mid-Holocene sea level in this area was discussed, and the Haishan Island was proposed to uplift with a rate of ~5 mm/a in the last -600 a. 展开更多
关键词 BEACHROCK coquinite DIAGENESIS evolution model mid holocene sea level
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THE IMPACTS OF ORBITAL PARAMETERS ON SUMMER PRECIPITATION OVER CHINA IN THE HOLOCENE
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作者 黄建斌 王绍武 +4 位作者 闻新宇 周天军 朱锦红 杨保 任国玉 《Journal of Tropical Meteorology》 SCIE 2011年第2期103-112,共10页
The impact of orbital parameters on the climate of China in the Holocene is simulated from 11kaBP to 0kaBP with an interval of 1ka using National Center for Atmospheric Research (NCAR) Community Atmosphere Model versi... The impact of orbital parameters on the climate of China in the Holocene is simulated from 11kaBP to 0kaBP with an interval of 1ka using National Center for Atmospheric Research (NCAR) Community Atmosphere Model version 2 (CAM2). The geographic distributions of summer precipitation around both 9kaBP and 4kaBP were realistically captured by CAM2, compared to the proxy data collected from 80 stations. Among all orbital parameters, the precession plays a major role in computing solar radiation, which dominates the variations of summer precipitation over China during the Holocene. The summers around 9kaBP were the wettest in China. Later on, the precipitation gradually reduced to the minimum around 0kaBP by about 10%. This tremendous change occurred from the Northeast China and the eastern Inner Mongolia extending southwestwards to the Qinghai-Tibet Plateau, especially over the Qinghai-Tibet Plateau. 展开更多
关键词 holocene climate simulation orbital parameters climate humidity
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High-Resolution Geochemical Records in the Inner Shelf Mud Wedge of the East China Sea and Their Indication to the Holocene Monsoon Climatic Changes and Events
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作者 WANG Longsheng ZHOU Bin +5 位作者 ZHENG Bang WANG Ke MEI Xi WANG Qing WANG Xiaohui ZHENG Hongbo 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第6期1409-1418,共10页
The inner shelf mud wedge(ISMW)located in the East China Sea(ECS)is the fine-grained sedimentary area with high sedimentation rate and has provided an ideal study area for understanding the East Asian Summer Monsoon(E... The inner shelf mud wedge(ISMW)located in the East China Sea(ECS)is the fine-grained sedimentary area with high sedimentation rate and has provided an ideal study area for understanding the East Asian Summer Monsoon(EASM)evolution during the Holocene.In this paper,we presented the high-resolution geochemical data of the sediments from the core MD06-3040 in the ISMW of the ECS determined by X-ray fluorescence core scanning(XRF-CS)analysis,a high-resolution,continuous,and multielement method.Geochemical and factor analysis results reveal that the variations of elemental compositions(Al,Si,K,Ti,Fe),the elemental ratios of Al/Zr,Ca/Ti and Rb/Sr,and the factor scores(F1 are correlated with the changes of the EASM during the period of 6000–1300 cal yr BP.The higher values of geochemical compositions indicating the terrigenous inputs implied the intensification of anthropogenic activities after 1300 cal yr BP.Meanwhile,the significant decrease of most geochemical compositions and the F1 factor scores during 4500–3500 cal yr BP and 1700–1500 cal yr BP,within the dating errors,coincided with the weak EASM events(presumably drought and cold events).The spectral analysis results of K concentrations,Al/Zr ratios and F1 factor scores show the millennial and centennial climatic fluctuations,which are consistent with other marine sedimentary records in the adjacent areas.All the findings show that the geochemical compositions of sediments from core MD06-3040 are influenced by the EASM evolution,the variable El Niño/Southern Oscillation(ENSO)and the local oceanic thermohaline circulation(e.g.,Kuroshio Current).These results are greatly helpful in uncovering the forcing mechanism of the monsoonal climate in the east China over the Holocene and also contribute to the understanding of EASM variability. 展开更多
关键词 holocene climatic event East Asian Summer Monsoon XRF core scanning inner shelf mud wedge
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