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Coupling controls of neotec-tonism and paleoclimate on the Quaternary sediments of the Yangtze (Changjiang) coast

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Science Bulletin 2005年第16期 105-114页

作者： WANG Zhangjiao1, chen zhongyuan2. WEI Zixin3, WANG Zhanghua1 & WEI Taoyuan1 1. Department of Geography,{2., shanghai 200062, china 2. State key laboratory for estuarine and coastal research,{2., shanghai 200062, china 3. {12. Institute of Geological Survey, {12. 2.0072. china

Attempt has been made to discuss the coupling relation of neotectonism and paleoclimate that have played a critical role in controlling the Quaternary sediment distribu-tion and sedimentary facies evolution on the Yangtze coast. On the basis of petrological analysis, up to six sedimentary cyclicities have been identified in the Quaternary sediment boreholes on the time scale of 0.4―0.5 Ma. The lower sedi-mentary cyclicities (Pliocene to Early Pleistocene) are char-acterized largely by thicker gravelly coarse sands, topped by thinner fine silt and silty clay. Gravels are very angular and clayey gravels prevail. Sediments are usually of poor sorting, rich in log fragments and have no microfossils. Bedload as denoted by C-M plot occurs throughout the section. This evidence represents the alluvial fan sedimentation which took place as the basin began to subside. The middle sedimentary cyclicities (often including Early to Middle Pleistocene) con-sist of basal gravelly sands and clayey silt at the middle and upper sediment sections. Sorting becomes relatively better, and foraminifer appears sporadically. C-M plot reveals the mixture of sediment transport media via bedload, saltation and suspension, representing sedimentation of braided river system at the early stage and subsequently, the sedimentation of meandering river pattern. The upper sedimentary cyclic-ities (including Late Pleistocene to Holocene) comprise basal gravelly sands (exclusive of the Holocene sediment) and thick fine sand and silty clay on the upper section. Sorting becomes fine and foraminifer appears throughout the sediment sec-tion. C-M plot shows that saltation and suspension serve as the main sediment transport media in the sediment section and bedload transport weakens. These evidence the sedi-mentation of meandering river pattern near coast during Late Pleistocene and Holocene time, when marine transgres-sion invaded into the paleoriver valleys, which often forms drowned-valley facies and shallo

关键词： Quaternary sediments grain size neotectonic subsidence paleoclimate/sea-level fluctuations Yangtze delta.

Spatial and temporal distribution of trace elements in Yangtze Estuary,china: Significance of diluted setting

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Chinese Science Bulletin 2001年第S1期46卷 65-73页

作者： WANG Zhanghua chen zhongyuan LI Luqian WEI Taoyuan Department of Geography East China Normal UniversityShanghai 200062China State key Laboratory for estuarine and {2. research East China Normal UniversityShanghai 200062China

The present study is to examine the spatial and temporal distribution of eight trace elements (Sr, Ba, B, Ga, Ni, V, Cu, and F) in various Holocene marine subfacies in the Yangtze Estuary, including its subaqueous delta by sediment borehole and vibrocore. Results demonstrate that grain size is the determinant factor in controlling the concentration of most trace elements discussed. Prodelta mud that occurs usually below the normal wave base can serve as a depository sink for trapping trace elements over the long-term time period. For example, copper concentration is 5-6 times higher than those found in the estuarine sediment. Boron, which is used to be a salinity indicator, shows a strong negative correlation with paleosalinity (using sediment phosphate method), implying desalinized water setting in the Yangtze Estuary, into which a large quantity of the Yangtze freshwater (92.×109 m3/a) has discharged. Trace element concentrations of the study area were compared with those collected from the middle

关键词： boron depository sink Holocene palaeosalinity prodelta mud trace elements transit environment Yangtze Estuary.

Coupling controls of neotec-tonism and paleoclimate on the Quaternary sediments of the Yangtze (Changjiang) coast

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Chinese Science Bulletin 2005年第16期50卷 1775-1784页

作者： WANG Zhangjiao chen zhongyuan WEI Zixin WANG Zhanghua WEI Taoyuan Department of Geography East China Normal University Shanghai200062 China State key laboratory for estuarine and {2. research East ChinaNormal University Shanghai 200062 China shanghai Institute of Geological Survey Shanghai 200072 China

关键词：扬子江流域地质气候沉积物谷物生理特性

Morphodynamic processes of the Elbe River estuary, Germany： the Coriolis effect, tidal asymmetry and human dredging

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Frontiers of Earth Science 2014年第2期8卷 181-189页

作者： Maotian LI Jianzhong GE Jens KAPPENBERG Dagmar MUCH Ohle NINO zhongyuan chen State key Laboratory of estuarine and {2. research East China Normal University Shanghai 200062 China Institute for coastal research Helmholtz-Zentrum Geesthacht Max-Planck-StralSe 1 Geesthacht 21502 Germany Hamburg Port Authority Neuer Wandrahm 4 Hamburg 20457 Germany

The Digital Elevation Model （DEM） based on the historical sea-charts and on-site hydrological records were used to examine the morphological change of the Elbe River estuary. The results show that siltation predominated in the tidal flat in the northern estuary, with a net siltation rate of 1.8 cm· a^-1 during 192.-2.06. In contrast, a continuous erosion prevailed in the main river channel, south of the estuary, with a net erosion rate of 2.5 cm· a^-1 in the same time. In addition, a seaward shift of the estuarine island has happened with the old island coalescing to the northern tidal flat and new one emerging through siltation process. The tidal asymmetry via ebbing flow （maximum at 140 cm· s^-1, and average at 76 cm· s^-1） prevailed in the tidal flat, meaning continuous aggradation northwestward, while flooding flow （maximum at 100 cm · s^-1, and average at 67 cm· s^-1） dominated in the main fiver channel with deepening thaweg at south, showing a landward sedimentation via the tidal pumping processes. This dextral extension of the estuarine morphology is due to the Coriolis force, leading to the inconsistent directions of in-out flows, which enables to facilitate the estuarine siltation. Human dredging prevailing in the estuary has dramatically altered the nature of the silted river channel to erosional since the last century net erosion rate of 3.2.cm· a^-1 This is characterized by a derived from the DEMs mapping, but only partially accounting for the dredging amount of 1994-2.06, when the total dredging volume was 67 × 10^6m^3, equal to 5.9 cm·a^-1.

关键词： morphological evolution dextral forcing,DEMs the Elbe River estuary

Clay minerals in the Pliocene-Quaternary sediments of the southern Yangtze coast, china: Sediment sources and palaeoclimate implications

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Journal of Palaeogeography 2014年第3期3卷 297-308页

作者： Jing chen Zhang-Hua Wang Tao-Yuan Wei Bao-cheng {2. Zhong-Yuan chen State key Laboratory of coastal and {2. research East China Normal University shanghai Geological Survey

Clay mineralogy was used as an indicator of the sediment source and prevailing climate and five suites （I-V） were identified throughout the borehole. Smectite was dominant in the bottom suite of the borehole, indicating the sediment was mainly derived from the local basalt when the study area stood as uplands during the Pliocene. The sharp reduction of smectite in suites II and III （Early Pleistocene） reflects a broader sediment provenance due to neo-tectonic subsidence of the study area. Significant climate fluctuations are indicated by distinct variations in the ratios of illite versus smectite and kaolinite, and by the illite crystallinity in suites II and IV. Especially the suite IV, which forms mottled muddy sediments that underwent pedogenesis, possibly represents glacial/interglacial cycles during the Mid-Pleistocene climate transition （MPT）. The rare presence of smectite in suite V which formed during the Late Quaternary suggests a significant contribution of fine-grained sediment derived from the upstream of the Yangtze catchment. Such changes in sediment sources are consistent with the evolution of regional sedimentary environments, which evolved towards an open coast/ deltaic setting and imply that the study area became the depositional basin of the Yangtze fine-grained sediment due to the final submergence of the Wu-Nan-Sha and Fukien-Reinan Massifs since the Late Quaternary.

关键词： smectite neo-tectonic subsidence Mid-Pleistocene climate transition,Yangtze depocenter Pliocene-Quaternary southern Yangtze coast

长江口横沙岛不同发育年限盐沼植被生长特征及其固碳功能差异

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华东师范大学学报（自然科学版） 2024年第1期 113-121页

作者：张晓涵田慧敏陈雪初杨华蕾丁睿赵明明由文辉华东师范大学生态与环境科学学院上海200241 华东师范大学河口海岸学国家重点实验室上海200241 崇明生态研究院上海202162

滨海盐沼湿地因长期淹水而具有较高的生产量和较低的分解率,储蓄了大量的土壤有机碳.随着新恢复盐沼湿地发育年限的增加,其植被生长特性、土壤理化性质与有机碳含量也发生了变化,进而影响到固碳增汇功能.本文以长江口横沙岛新恢复盐沼... 详细信息

滨海盐沼湿地因长期淹水而具有较高的生产量和较低的分解率,储蓄了大量的土壤有机碳.随着新恢复盐沼湿地发育年限的增加,其植被生长特性、土壤理化性质与有机碳含量也发生了变化,进而影响到固碳增汇功能.本文以长江口横沙岛新恢复盐沼湿地为例,利用时空代换法,分析新恢复湿地不同发育年限与不同植被群落类型的植被生长性状及土壤有机碳变化情况,并分析影响新恢复湿地固碳能力的关键因子.结果表明:新恢复盐沼湿地在0~2.年内有机碳含量随发育年限的增长而增加,且土壤孔隙度和含水率变化可有效指示土壤有机碳的变化;新恢复湿地具有较高的土壤碳密度,发育8年的湿地0~2. cm土层的总有机碳密度为(2..49±3.67)tC·hm^(-2.,接近自然湿地;芦苇恢复湿地植被长势和固碳能力高于海三棱藨草和芦苇–海三棱藨草交错群落.

关键词：新恢复湿地盐沼植被土壤有机碳碳密度蓝碳

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Simulation of transport mechanism of radium isotopes in aquifer on the southern coast of Laizhou Bay

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海洋学报:英文版 2023年第8期42卷 40-48页

作者： Yancheng Wang Guangquan chen Hongjun Yu Xingyong Xu Yinqiao Zou Wenqing {2. Weitao Han Wenzhe Lyu Zhen Cui Runtian Ding key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China Fourth Institute of Oceanography Ministry of Natural ResourcesBeihai 536000China Weifang Institute of Marine Development Weifang 261041China State key Laboratory of estuarine and {2. research East China Normal UniversityShanghai 200241China Qingdao Hailukong Environmental Automatic-control Engineering Co. Ltd.Qingdao 266000China

Naturally occurring radium(^(2.3)Ra,^(2.4)Ra,^(2.6)Ra,and^(2.8)Ra)isotopes have been widely applied as geochemical tracers in marine environments,especially when estimating the submarine groundwater discharge(SGD).In this sense,the influencing factors and transport mechanism of radium isotope activity in aquifers can be key information for SGD *** work evaluates the adsorption/desorption behavior of^(2.4)Ra and^(2.6)Ra in the solid-liquid phase through a leaching experiment and analysis of field *** results suggested that radium isotope activity was positively correlated with salinity and grain size,in the case of abundant *** ion analysis,we found that the ions(Na^(+),Ca^(2.),Mg^(2.),and Ba^(2.))exchanged with radium isotopes in the process of transport.A 1-D reactive transport model was established to simulate the transport process of radium isotope in *** model successfully simulated the variation of radium isotope desorption activity with salinity and was subsequently verified in the *** study contributes to the understanding of the geochemical behavior of radium isotopes in aquifers and provides guidance for selecting a suitable groundwater endmember in SGD estimation.

关键词： radium adsorption/desorption behavior leaching experiment reactive transport model coastal aquifer Laizhou Bay

三沙湾潮滩涨落潮和大小潮冲淤特征及其动力机制

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海洋地质前沿 2024年第3期40卷 48-54页

作者：赵元楷李茂田曾剑威陈静刘晓强姚慧锟刘演樊春谭子杰张雯彦彭旦华东师范大学河口海岸学国家重点实验室上海200241 中国地质调查局南京地质调查中心南京210016 华东师范大学崇明生态研究院上海202162

潮滩不同尺度的变化规律一直是地表过程研究的核心之一。利用声学多普勒流速仪(ADV)、温盐深(CTD)、光学后向散射浊度计(OBS)对三沙湾潮滩涨落潮和大小潮冲淤及动力变化进行了高精度的观测。结果发现,潮周期内,潮滩冲淤呈现涨潮初期冲刷... 详细信息

潮滩不同尺度的变化规律一直是地表过程研究的核心之一。利用声学多普勒流速仪(ADV)、温盐深(CTD)、光学后向散射浊度计(OBS)对三沙湾潮滩涨落潮和大小潮冲淤及动力变化进行了高精度的观测。结果发现,潮周期内,潮滩冲淤呈现涨潮初期冲刷-落潮末期淤积-中间时段稳定的特征,涨潮初期水深2.mm,中间时段动态稳定;大小潮周期内,呈现中潮到小潮平均淤积3.4 mm,小潮到大潮平均冲刷8.2.mm的特征。通过流速、紊动能、水深、悬沙浓度等因子与冲淤的相关性分析发现,潮周期内,流速和紊动能的增减决定涨潮初期冲刷和落潮末期淤积的变化;大小潮周期内,涨潮冲刷大于落潮淤积的特性决定了大潮到小潮阶段的冲刷,涨潮冲刷小于落潮淤积决定了小潮到大潮阶段的淤积。涨落潮周期和大小潮潮周期的冲淤机制为潮滩动力地貌和动力沉积学研究提供了一定的参考。

关键词：三沙湾潮滩潮周期冲淤动力机制

Assessment of macrobenthic community function and ecological quality after reclamation in the Changjiang(Yangtze)River Estuary wetland

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Acta Oceanologica Sinica 2022年第11期41卷 96-107页

作者： Yinying Huang Yingying Huang Xinglin Du Yiming Li Jiangtao Tian Qiang chen Youhui Huang Weiwei Lv Ying Yang Zhiquan Liu Yunlong zhao State key Laboratory of estuarine and {2. research East China Normal UniversityShanghai 200241China School of Life Science East China Normal UniversityShanghai 200241China School of Life and Environmental Sciences Hangzhou Normal UniversityHangzhou 310018China shanghai Runzhuang Agricultural Science and Technology Co. LtdShanghai 201400China

An ecological optimization project(semi-closed reclamation project)was implemented to control the invasion of Spartina alterniflora,and optimize the habitat of the Chongming Dongtan wetland,in the Changjiang(Yangtze)River *** project implementation,a macrobenthic ecological survey was conducted in a natural tidal flat and a semi-closed reclamation restoration area within the Chongming Dongtan wetland from 2.19 to *** with historical data before reclamation,findings showed that the groups,numbers,and species diversity of the macrobenthos increased significantly,and the ecological optimization project resulted in good ecological *** addition,compared to the natural tidal flat,the number of collected macrobenthic phyla,and the macrobenthic density and biomass were significantly lower in the restoration ***,the biodiversity index and functional redundancy of natural tidal flats were generally higher,indicating that the community composition and function of natural tidal flats were relatively more *** though the species composition differed between a number of restoration areas and natural tidal flats,there was no difference in functional diversity,indicating that the effect of restoring ecological functions in restoration areas was *** them,the biodiversity and functional redundancy of Site S2.were significantly reduced,and the ecosystem function was extremely *** heterogeneity,vegetation community and decreasing salinity were the main factors that affected the ecological functions of *** ecological quality was also evaluated;the Transects N3 and N4 showed good *** overall ecological quality of the restoration area was generally high,but that of Site S2.was poor and that of Site S2. was merely good,which was mainly due to modifications of the ecological function of *** is suggested that reeds mowing and freshwater species release should be adopted in restoration area

关键词： macrobenthos ecological optimization project semi-closed reclamation community restoration functional diversity ecological health