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Spatial distribution and accumulation of heavy metals in tidal flat sediments of Shanghai coastal zone

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Science China Chemistry 2001年第S1期44卷 197-208页

作者：陈振楼刘培芳许世远柳林余佳俞立中 state key laboratory for estuarine and coastal sediment dynamics and morphodynamics East China Normal University Shanghai China

Surface and core sediments from the high, middle and low tidal flats of Shanghai coastal zone were analyzed for heavy metal (e.g. Cu, Pb, Zn, Cr, Cd, Fe, Mn) concentrations. Besides Cd, the concentrations of Cu, Zn, Cr and Pb are 2-5 times higher than their background values and show serious pollution trend due to the direct discharge of industrial and municipal sewage along the Shanghai tidal flat, as well as the wet and dry depositions of industrial dusts. It seems that heavy metals prefer to accumulate and be enriched in the sediments near large sewage outlets, high flats, and the subsurface layer at the depth of 10-30 cm. Several main factors, which include the direct sewage discharge along the tidal flat, tidal hydrodynamic action, large engineering activity, early diagenesis and windstorm tide, are considered to be responsible for influencing spatial distribution patterns of heavy metals in the Shanghai tidal flat.

关键词： Shanghai coastal zone tidal flat sediments heavy metals spatial distribution spatial accumulation.

EAST CHINA SEA RESPONSE TO TROPICAL CYCLONES

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Chinese Journal of Oceanology and Limnology 1996年第4期14卷 337-342页

作者：朱建荣杜荣华 state key laboratory for estuarine and coastal morphodynamics and sediment dynamics East China Normal University Shanghai 200062 Institute of Oceanology Chinese Academy of Sciences Qingdao 266071

The response of the East China Sea (ECS) to a tropical cyclone (TC) is studied with a two-layernonlinear primitive equation ocean model. Numerica experiments indicate that there is rightward bias inocean response to a moving TC. The initial middle layer (ML) depth and stratification intensity havesubstantial impact on the Changes of SST and ML depth. The initial ML depth has large effect onthe value of the current, whereas the initial stratification intensity has slight influence on it. Thedistribution of ECS ML depth, especially the special ocean thermal structure on the continental shelf facil-itates the drop of SST. The simulation results of ocean response to Typhoon 7002 are fairly consistentwith the observation data.

关键词： ocean model tropical cyclone mixed layer entrainment

sediment dynamics in the mudbank of the Yangtze River Estuary under regime shift of source and sink

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International Journal of sediment Research 2022年第1期37卷 97-109页

作者： Dai Zhang Weiming Xie Jian Shen Leicheng Guo Yu Chen Qing He state key laboratory of estuarine and coastal Research East China Normal University Virginia Institute of Marine Science College of William & Mary

The southeastern portion of the Yangtze River Estuary (or Yangtze Estuary) was considered to be the deposition center and the mudbank of the Yangtze River *** the fluvial sediment supply began to decline in the 1980s and the reduction accelerated after the completion of the Three Gorge Dam in 2003,more fluvial sediment was trapped decreasing the suspended sediment concentration (SSC) environment in the river mouth ***,the accretion rate of the mudbank has slowed down in recent *** fact,the mudbank shrank and has faced a regime shift from sediment sink to source.A better understanding of the tidal-scale dynamics and spatial variability of the system is essential to explore the conversion of the sediment sources and sinks in the Yangtze Estuary affected by natural variations and human *** velocity,salinity,and suspended-sediment concentration during spring and neap tides were measured at three sites on the mudbank in July 1982 and July *** variation in flow was not significant at all the sites measured in the study area from 1982 to ***,the sediment dynamics changed remarkably over these three *** temporal distribution of the SSC increased in the bottom *** SSC was much larger during the early flood tide period in *** tidal range increased by nearly 10%and the flood dominance increased in the study area from 1982 to *** salinity dynamics underwent a transition from a stratified system in 1982 to a well-mixed system *** landward sediment budget increased remarkably from 1982 to *** decreased fluvial sediment supply,increased flood dominance,well-mixed salinity,and increased tidal range were directly responsible for the larger landward sediment budget and more severe erosion in the mudbank in *** current results reveal the flow and sediment dynamics during the conversion of the sediment sink to ***,it was determined that the sediment-starved process in the estuarine e

关键词： Sink-source shift Fluvial sediment reduction sediment flux Yangtze River Estuary

Denitrification in Chongming east tidal flat sediment, Yangtze estuary, China

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Science China Earth Sciences 2006年第10期49卷 1090-1097页

作者： WANG Dongqi1,2, CHEN Zhenlou1,3, XU Shiyuan1,2, HU Lingzhen1 & WANG Jun1,2 1. College of Resources & Environment, East China Normal University, Shanghai 200062, China 2. state key laboratory of estuarine and coastal sediment dynamics and morphodynamics, East China Normal University, Shanghai 200062, China 3. key laboratory of Geographical Information Science of Ministry of Education,East China Normal University,Shanghai 200062, China College of Resources & Environment East China Normal University Shanghai China state key laboratory of estuarine and coastal sediment dynamics and morphodynamics East China Normal University Shanghai China key laboratory of Geographical Information Science of Ministry of Education East China Normal University Shanghai China

From July 2003 to July 2004, samples were collected on Chongming Island east tidal flat every two months. The research showed that the nitrous oxide (N2O) production rate was very low in the water, Chongming east tidal flat (CM) sediment was the N2O source of the water. sediment N2O natural production rate was between -0.08 and 1.74 μmolN·m-2·h-1. N2O natural production rate was higher in the summer. The difference of the N2O natural production rate in the different tidal flats, the correlation between the N2O natural production rate and the denitrification rate, and those with the temperature and DO indicate that middle tidal flat sediment denitrification was the main process of the N2O production, while in the low tidal flat sediment, the production of the N2O came from several processes of the nitrogen cycling. Tidal flat sediment denitrification reaction was stronger in summer and winter but relatively lower in the late autumn and early spring. Seasonal change of the sediment denitrification rate was wide, from 1.12 to 33.34 μmolN·m-2·h-1. Temperature, DO and the coactions of them had the prominent effect on the tidal flat sediment denitrification.

关键词： Yangtze estuary, tidal flat sediment, denitrification, nitrous oxide, effect factor.

Sources and degradation of organic matter in the surface sediments of the Chukchi Sea:insights from amino acids

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Acta Oceanologica Sinica 2023年第11期42卷 9-18页

作者： Weiwei Li Zhongqiao Li Zhuoyi Zhu Alexander Polukhin Youcheng Bai Yang Zhang Futao Fang Haiyan Jin Anatolii S.Astakhov Xuefa Shi Jianfang Chen key laboratory of Marine Ecosystem and Biogechemistry Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Shanghai key laboratory of Polar Life and Environment Sciences School of OceanographyShanghai Jiao Tong UniversityShanghai 200240China key laboratory for Polar Science of Ministry of Natural Resources Polar Research Institute of ChinaShanghai 201209China laboratory of Biohydrochemistry Shirshov Institute of OceanologyRussian Academy of SciencesMoscow 117997Russia state key laboratory of estuarine and coastal Research East China Normal UniversityShanghai 200241China V.I.Il’ichev Pacific Oceanological Institute Far Eastern BranchRussian Academy of SciencesVladivostok 690012Russia key laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China state key laboratory of Satellite Ocean Environment dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

In the context of global warming and rapid environment change in the Arctic,the supply of organic matter(OM)has increased significantly and a large amount of OM are buried on the Arctic *** the fate of OM in Arctic shelf sediments is crucial to understanding the global carbon *** a marginal sea of the Arctic Ocean,the Chukchi Sea is one of the most critical areas where OM is *** on the surface sediment samples collected during the sixth Chinese National Arctic Research Expedition in the summer of 2014 and the SinoRussian joint Arctic Research Expedition in the summer of 2016,this study takes amino acids(AAs)as the primary tool to explore the source and degradation of OM in the surface sediments of the Chukchi *** study shows that total hydrolyzable amino acid(THAA)concentrations(dry weight)are high,with a mean value of(32.7±15.8)μmol/*** spatial distribution is related to primary productivity,hydrodynamic conditions,sediment properties and other *** source of OM in the surface sediments of the Chukchi Sea is dominated by diatom-dominated marine productivity,with some input from terrestrial ***,as the main source of the D-enantiomer of AA(D-AA),not only have transforming effect on OM,but their cell walls and remnants likewise supply the OM *** on a series of diagenetic indicators,we conclude that the OM in the surface sediments of the Chukchi Sea has undergone extensive degradation[DI(degradation index)=-0.59±0.44],and the degradation degree in the slope is higher than that in the *** study uses AA to explore the sources and degradation of OM in the sediments of the Chukchi Sea,which facilitates our understanding of OM transport and transformation on the Arctic shelf.

关键词： Chukchi Sea amino acids degradation indicator organic matter

Progress of estuarine research in China over last 50 years

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Science China Chemistry 2001年第S1期44卷 1-9页

作者：陈吉余李道季陈沈良 state key laboratory of estuarine and coastal Research East China Normal University Shanghai China

It is well known that the estuarine research in China has got great achievements since the past 50 years. The development of estuarine research in China and progress in fundamental study are presented firstly in this paper. Especially in the aspect of theoretic studies, a distinctive feature is the combination studies of dynamics, sedimentology and geomorphology, which obtain a series of achievements, such as estuarine diluted water, estuarine fronts, turbidity maximum, sediment movement, formation of mouth bar, estuarine discontinuity phenomena, estuarine development, etc. Then some successful applications are introduced taking the Qiantang River Estuary and Yangtze Estuary as examples. Finally, main directions of estuarine research are discussed on fundamental study, the impacts of human activities on estuaries, estuarine material flux, sediment movement, prediction of estuarine erosion and accretion, estuarine discontinuity, artificial estuaries, land reclamation and wetland protection.

关键词： China estuarine research progress reviews.

Study on Volume Variation and Stability of Riverbed in the Yangtze Estuary

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China Ocean Engineering 2023年第3期37卷 433-446页

作者： DING Lei JIAO Jian TONG Chao-feng WANG Yi-fei CHEN Ben SUN Jie-ying DOU Xi-ping key laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China state key laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China

In recent years,regional floods and typhoons have occurred in the Yangtze *** dynamic conditions and dramatic reduction of sediment discharge in the basin are affecting the dynamic equilibrium pattern of the Yangtze *** on the field measurement data and theoretical derivation,this paper analyzed the changing process of runoff-sediment discharge into the sea after the operation of the Three Gorges Project(TGP),and the tidal dynamics and sediment variation characteristics of the Yangtze *** erosion of South Branch mainly occurs in the channel below-10 m contour,and the riverbed volume below contours 0 m and-10 m has a good correlation with the sediment discharge of Datong Station in the previous *** this basis,the ratio of the horizontal distance from the starting point to the section centroid below the average water level(B_c)and the water depth at the section centroid(H_c)was proposed to describe the change of the section *** relationships between the water-diverting ratio,the sediment-diverting ratio and the water-diverting angle,the conditions of runoff and sediment discharge from the upper reach and the characteristics of the riverway section were established,and the theoretical calculation equations of the water-diverting ratio,the sediment-diverting ratio and the diverting angle of each bifurcation were also established.

关键词： Yangtze Estuary volume variation section shape riverbed stability

Distributions of surficial sediments and its response to dynamic actions in the Xiamen Bay sea area, China

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Acta Oceanologica Sinica 2016年第4期35卷 9-18页

作者： ZUO Shuhua HAN Zhiyuan HUANG Yunxin HAN Jie XIE Mingxiao National Engineering laboratory of Port Hydraulic Construction Technology Tianjin Research Institute of Water Transport Engineering key laboratory of Engineering sediment of Ministry of Transport Tianjin Research Institute of Water Transport Engineering state key laboratory of estuarine and coastal Research East China Normal University School of Science Tianjin University of Technology

sediment distribution is important for morphodynamic evolution and shoreline changes in coastal zones and estuaries. In the study, the data of 230 surface sediment samples collected from the Xiamen Bay sea area in September 2008 are used to investigate the spatial distribution and sediment transport pathway. The grain size distribution of surficial sediments in the Xiamen Bay area is shown distinctly in this study. In addition, the Grain Size Transport Analysis model is used for conveying trend analysis of the sediment in this area, particularly for determining the sediment movement trend. The results indicate that eight sediment types are present for samples, with clayey silt comprising the highest percentage in the study area at 65.22%. Moreover, in the different subareas, the characteristics of grain size parameters are obviously different owing to different sediment sources and hydrodynamic conditions. Furthermore, runoff, tides, and waves are the main forces dominating sediment dynamics on the seabed and tidal flats, and the sediment movement trend is closely related to hydrodynamic conditions.

关键词： Xiamen Port Jiulongjiang Estuary Xiamen Bay surface sediments grain size dynamic response

Carbon isotopes and lignin phenols for tracing the floods during the past 70 years in the middle reach of the Changjiang River

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Acta Oceanologica Sinica 2020年第4期39卷 33-41页

作者： Zhongqiao Li Ying Wu Liyang Yang Jinzhou Du Bing Deng Jing Zhang state key laboratory of estuarine and coastal Research East China Normal UniversityShanghai 210012China key laboratory of Marine Ecosystem dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China College of Environment and Resources Fuzhou UniversityFuzhou 350108China

The Lake Tian E Zhou(TEZ,an oxbow lake)was formed during the rerouting of the Changjiang River in 1972,with strong influences from the main river channel and flood ***,a sediment core was collected from the Lake TEZ for the measurements of carbon isotopes and biomarkers,including stable carbon isotopes(δ13C),radiocarbon composition(?14C),and lignin phenols,as well as lead-210 to reconstruct recent heavy flood events over the past 70 *** the 24–26 cm interval,the sediment contained the highest OC%,TN%,and lignin phenols content,as well as significantly depleted 13C but enriched 14C,corresponding to the extreme flood event in *** addition,statistics from t-test showed that lignin phenols normalized to OC(Λ8),the concentration of 3,5-dihydroxy benzoic acid(3,5-BD),and the ratio of p-hydroxy benzophenone to total hydroxyl phenols(PHB/HP)were all significantly different between the layers containing flood deposits and the layers deposited under normal non-flood conditions(psediment chronology,for hydrological changes and storm/flood events in the river basin and coastal marine environments.

关键词： flood record carbon isotopes lignin phenols Changjiang River Lake Tian E Zhou