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Chinese Science Bulletin 2005年第24期50卷 2878-2884页

作者： WANG Houjie yang zuosheng BI Naishuang LI Haidong College of Marine Geosciences Ocean University of China Qingdao 266003 China

Freshwater plume represents a key passage for the river to deliver sediment to the coastal ocean. A wa- ter-sediment regulation scheme was implemented for the Huanghe River in 2005; in order to examine the effect of such an activity on the river plume dynamics, three cruises were carried out off the Huanghe River mouth. The prelimi- nary results of the in-situ measurements suggested that the plume pathway shifted rapidly during the period of less than twenty days, which was confirmed by satellite remote sensing data in the same period. The rapid shifts were resulted from intensive interactions between river discharge and the vary- ing bathymetry in the river mouth area. A large amount of river sediment was delivered to the coastal region during this period and mostly deposited in the mouth bar area due to jet-flow deceleration, forming a cluster of mouth bars across the river mouth, which caused the rapid shifts of the plume pathway.

关键词：黄河河口卷流泥沙沉积规则 2005年

Heavy metals in surficial sediments of the central Bohai Sea:their distribution,speciation and sources

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Acta Oceanologica Sinica 2016年第9期35卷 98-110页

作者： LIU Ming FAN Dejiang LIAO Yongjie CHEN Bin yang zuosheng Key Laboratory of Submarine Geosciences and Technology of Ministry of Education College of Marine GeosciencesOcean University of China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Qingdao Institute of Marine Geology Ministry of Land and Resources

The semi-enclosed Bohai Sea has received large amount of pollutants from surrounding rivers and sewage channels along the densely populated and industrializing Bohai coasts,as well as the offshore oil exploration in the *** concentrations of heavy metals copper,cobalt,nickel,zinc,lead,chromium and cadmium in 25 surface sediment samples from the central Bohai Sea are obtained by ICP-MS *** speciation of these heavy metals is extracted and their distribution,fractionation,pollution status and sources are *** concentrations of copper,cobalt,nickel,zinc and chromium are found in the sediments off the coastal area of the Bohai Bay and the central Bohai Sea mud,while high concentrations of cadmium and lead are found in the sediments in the whole study *** residual fraction is the dominant form of copper,cobalt,nickel,zinc and chromium in the surface sediments,while cadmium and lead have large proportions in the nonresidual *** ecological risk assessment shows that the sediments in the study area are unpolluted with respect to the heavy metals of cobalt,nickel and chromium and unpolluted to moderately polluted with respect to copper,zinc,cadmium and ***,nickel and chromium mainly have natural origin and their concentrations significantly vary with the composition of the *** contents of copper,zinc,lead and especially cadmium in sediments are suggested to be influenced by pollutants of human *** heavy metals in the surface sediments at most sampling stations are mainly come from the Huanghe River; the heavy metals in the sediments in the northernmost part of the study area are significantly affected by the sediment from the Luanhe River; while in the Bohai Bay and the central region they were affected by the sediment from the Haihe River and aerosol deposition.

关键词： heavy metal central Bohai Sea speciation environment quality source

Longitudinal residual circulation in the South Passage of yangtze Estuary:Combined influences from runoff,tide and bathymetry

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Science China Earth Sciences 2021年第12期64卷 2129-2143页

作者： Lifen ZHANG zuosheng yang Fan ZHANG Zhanhai LI Yaping WANG Shu GAO State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai200062China College of Marine Geosciences Ocean University of ChinaQingdao266100China School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing210023China

Classical estuary circulation theory states that in the longitudinal direction of an estuary there exists a single circulation with landward,near-bottom,and seaward,near-surface flows;however,the situation becomes complicated with the presence of a river mouth *** we conducted tidal-cycle observations in the South Passage of the yangtze Estuary during both the wet and dry seasons of 2018(July and December,respectively).The simultaneous current velocity,temperature,and salinity profile data were obtained from anchored boats and base tripods at three stations along the channel in the mouth bar *** results reveal two distinct longitudinal residual circulation patterns:a classic circulation which is formed on the seaward slope of the mouth bar during the wet season,and a double circulation system which is composed of two circulation cells over the landward and seaward slopes of the mouth bar during the dry *** Simpson number(Si),mixing parameter(M),and salinity data were used to quantify the mixing intensity,which shows that horizontal baroclinic pressure gradient is the dominant factor in the formation of the longitudinal residual ***,the double circulation pattern during the dry season is related to the mouth bar bathymetry,which affects saltwater *** double circulations can significantly influence the spatial and temporal evolution of the stagnation point in the estuarine channel,which in turn modifies the distribution patterns of suspended sediment concentration in the maximum turbidity ***,the changes in the mouth bar sandbar bathymetry in response to human activities and river basin hydrographic conditions indirectly affect the occurrence and scale of the double circulations.

关键词： Longitudinal residual circulation Tidal straining River mouth bar Double circulations Estuary turbidity maximum yangtze River

Organic carbon and nitrogen isotopes in surface sediments from the western Arctic Ocean and their implications for sedimentary environments

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Acta Oceanologica Sinica 2006年第5期25卷 39-54页

作者： CHEN Zhihua SHI Xuefa CAI Deling HAN Yibing yang zuosheng Ocean University of China Qingdao 266003 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Key Laboratory of Marine Sedimentology ＆ Environmental Geology of State Oceanic Administration First Institute of Oceano-graph State Oceanic AdministrationQingdao 266061 China

Surface sediments from the Chukchi Sea and adjacent arctic deep sea were investigated for organic carbon and nitrogen isotopes （in δ13Corg and δ15Norg） as well as biogeni＇c silica （BSiO2）. δ13Corg and δ15Norg values of surface sediments in the study area fall between the end-member values of marine and terrestrial organic matter from the surrounding lands and seas, their variations reflect the changes of marine productivity and terrestrial supply in the study area. BSiO2 shows a similar distribution pattern with δ13Corg and δ15Norg, and can be used as an indicator of marine productivity. In the central-west Chukchi Sea and the Chukchi Rise, sediments have higher δ13Corg, δ15Norg and BSiO2 values, indicating the region has high marine productivity influenced by the nutrient-rich branches of the Pacific waters. In the coastal zone off northwestern Alaska, δ13Corg and δ15Norg values become lighter, indicating a weakening marine productivity and an increasing terrigenous supply due to the effects of the least nutrient-rich branch of the Pacific waters. In the north and the northeast of the study area （including the Chukchi Plateau, the Canada Basin and the Beaufort shelf）, δ13Corg, δ15Norg and BSiO2 have the lowest values, and the terrigenous organic matter becomes dominant in surface sediments because this region has the longest ice-covered duration, the least nutrient-rich seawater and the increasing supply of terrestrial materials from the Mackenzie River and the northern Alaska under the action of the clockwise Beaufort gyre. Because the subarctic Pacific waters are continuously discharged into the central basin of the Arctic Ocean through the study area, the nutrient pool in the Chukchi Sea can be considered as a typical open system, the ratio of δ15Norg to BSiO2 content show some tracers that the level of nutrient utilization is contrary to nutrient supply and marine productivity formed in seawater.

关键词： western Arctic Ocean surface sediments organic carbon and nitrogen isotopes biogenic silica

Characteristics and Origins of Suspended Pyrite in the Mixing Zone of the yangtze Estuary

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Journal of Ocean University of China 2020年第4期19卷 801-810页

作者： PANG Yue FAN Dejiang SUN Xiaoxia SUN Xueshi LIU Ming yang zuosheng Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology(QNLM)Qingdao 266061China Center for Isotope Geochemistry and Geochronology Qingdao National Laboratory for Marine Science and Technology(QNLM)Qingdao 266061China

For a long time,most studies about pyrite have focused on sediments while only a few have focused on pyrite in *** this study,a method that combines the scanning electron microscopy(SEM)and the energy dispersive X-ray spectrometry(EDS)was used to compare pyrite particles suspended in water to those in associated bottom sediments,both obtained from the mixing zone of the yangtze *** was found that the pyrite particles in the two media have similar morphologies and size *** particle morphology mainly includes two types,single crystal and aggregate,and the particle size mainly ranges from 0.5 to 2μ*** pyrite particles in water exhibit an increase in relative content towards the sea,and their transport and deposit processes are mainly affected by hydrodynamic *** is concluded that the pyrite particles in the suspended matter mainly derived from the resuspension of sediments,which are products of the early *** minerals may appear during the formation of pyrite,but are generally restricted by the diagenetic environment and local microenvironment.

关键词： yangtze Estuary suspended matter pyrite resuspension authigenic mineral

Boosting spring runoff into the sea by reservoir regulation and its potential for estuarine fishery recovery

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Science China Earth Sciences 2024年第5期67卷 1591-1603页

作者： Xiao WU Houjie WANG Yongyong FAN Naishuang BI Chiyuan MIAO Jingping XU zuosheng yang College of Marine Geosciences Key Laboratory of Submarine Geosciences and Prospecting Technologyand Frontiers Science Center for Deep Ocean Multispheres and Earth SystemOcean University of ChinaQingdao 266100China Laoshan National Laboratory Qingdao 266061China Institute of the Yellow River Estuary and Coast Science Dongying 257000China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Ocean Science&Engineering Southern University of Science and TechnologyShenzhen 518055China

With global surge in reservoir construction over the past decades,river systems worldwide have been profoundly ***,flow manipulation by reservoirs has altered the natural hydrological processes,resulting in extensive modifications of fluvial-marine *** the adverse ecological consequences of reservoirs has become a global concern and has garnered increasing *** Yellow River,as one of the most extensively manipulated river systems globally,has experienced substantial changes in the amount and timing of water discharge due to the presence of numerous reservoirs scattered throughout its catchment *** alterations have caused physicochemical changes in the estuary and subsequent modifications to the estuarine *** recent years,the Yellow River Conservancy Committee initiated the release of water through the Xiaolangdi Dam during the major spawning period of fisheries,specifically in the spring,with the aim of improving the estuarine ecological *** 2011 to 2020,a total of 84.05 km^(3)of water was discharged from the Xiaolangdi Reservoir during spring seasons,of which 40%(33.16 km^(3))constituted water impounded within the reservoir during preceding ***,the spring water discharge from the Yellow River to the sea increased significantly from 1.50 km^(3)/yr to 3.46 km^(3)/yr in the past decade,leading to a decrease in estuarine salinity by 1.6 *** estuarine fishery resources,such as fish eggs in the Yellow River estuary,have demonstrated evident *** reservoir regulation in the Yellow River,which has successfully enhanced spring water discharge and subsequently restored estuarine fishery resources,presents an effective attempt for mitigating the adverse ecological effects associated with reservoirs.

关键词： Reservoir regulation Water release Spring runoff Estuarine ecosystem Yellow River

The Mineral Composition and Sources of the Fine-Grained Sediments from the 49.6?E Hydrothermal Field at the SWIR

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Journal of Ocean University of China 2020年第1期19卷 60-68页

作者： ZHANG Wenqiang SUN Xiaoxia FAN Dejiang LIU Ming JIA Qi yang zuosheng Key Laboratory of Submarine Geosciences and Technology MOEOcean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China

We used the X-ray diffraction method to determine systematically the mineral phases in bulk sediment samples and acid undissolved residuals of the fine-grained fraction of the surface sediments from the 49.6°E hydrothermal field at the Southwest Indian Ridge(SWIR)and discussed the mineral sources of the surface *** results showed that the surface sediments in this region were composed of calcareous ooze,and calcite was the dominant *** sediments also contained quartz,feldspar,clay minerals,pyroxene,sphalerite,barite,serpentine,and *** quartz,feldspar,and clay minerals were exogenous minerals that mainly originated from the Namib and Kalahari deserts in southern *** pyroxene,serpentine,magnetite,sphalerite,calcite,and barite were endogenous minerals from weathering of seafloor basement rocks and seafloor hydrothermal *** sulfide particles in the sediments were mainly deposited from upwelling plumes.

关键词： Southwest Indian Ridge surface sediment mineral source hydrothermal

Sustained growth of the largest uninhabited alluvial island in the Changjiang Estuary under the drastic reduction of river discharged sediment

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Science China Earth Sciences 2021年第10期64卷 1687-1697页

作者： Xiaodong ZHANG Rui XIE Daidu FAN zuosheng yang Hongmin WANG Chuang WU Yuhan YAO Key Lab of Submarine Geosciences and Prospecting Techniques MOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China

The evolution of the Changjiang Delta is obviously affected by current rapidly rising sea level and drastically declining river discharge,and it is also vital for the sustainable development of Shanghai and the Changjiang River Economic Belt,which represent China’s economic development leader and major national strategic area,*** this paper,the growth pattern of Jiuduansha Island,the largest uninhabited alluvial island in the Changjiang Estuary,is studied in terms of the change in elevation,position and area over the past 50 years through using satellite-derived instantaneous shoreline positions and high/low tide exposure areas based on 497 satellite images from 1974 to 2020;and the influencing factors and future development patterns are further discussed by comparison with other alluvial islands or sandbars in the *** results show that Jiuduansha Island has maintained a rapid or even accelerated area growth rate,although the sediment discharge of the Changjiang River has sharply decreased in recent *** sustained growth is mainly attributed to the existence of the estuarine turbidity maximum zone,coarsening fluvial sediment,onshore sediment replenishment by tide,cone-like geomorphology of Jiuduansha Island,and siltation promotion effect of *** growth rate of the low tide exposure area of Jiuduansha Island increased from 1.9 km^(2)a^(−1) in 1974–1990 to 3.0 km^(2)a^(−1) in 1990–2020,and the growth rate of the high tide exposure area reached as high as 3.7 km^(2)a^(−1) in 1994–*** implementation of the Deep-Water Channel Project has significantly affected the evolution of Jiuduansha Island,including shifting the heads of Shangsha and Zhongxiasha from severe retreat to rapid accretion,and promoting tidal flat progradation seaward of the Jiangyanansha and Zhongxiasha,but restricting the growth of the low tide exposure area of Jiuduansha Island.

关键词： Delta evolution Changjiang Estuary Jiuduansha Island Sandbar and sand island Satellite image

Biomarker evidence for changes in terrestrial organic matter input into the Yellow Sea mud area during the Holocene

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Science China Earth Sciences 2016年第6期59卷 1216-1224页

作者： WU Peng XIAO XiaoTong TAO ShuQin yang zuosheng ZHANG HaiLong LI Li ZHAO MeiXuna Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Ministry of Land and ResourcesQingdao 266071China Third Institute of Oceanography State Oceanic Administration(SOA)Xiamen 361005China College of Marine Geoscience Ocean University of ChinaQingdao 266100China

We present lipid biomarker records of two cores （ZYI and ZY3） from the central South Yellow Sea mud area to investigate the changes in sources and transport processes of the sedimentary organic matter （OM） throughout the Holocene. Based on the analysis of marine biomarker content （EPB （Phytoplankton Biomarker, total content of brassicasterol, dinosterol and C37-alkenones） and crenarchaeol）, and terrestrial biomarkers （En-alkanols and brGDGTs） as well as TMBR＇ and BIT index values, the marine organic matter （MOM） and terrestrial organic matter （TOM） deposition history was reconstructed. Changes in TOM and MOM were related to variations in land vegetation density and marine productivity, as well as transport processes dominated by the oceanic circulation system. The marine biomarker contents from the South Yellow Sea have generally in- creased throughout the Holocene, indicating that the increased MOM contents were mainly controlled by the strengthening of the circulation system. The terrestrial biomarkers, on the other hand, were more variable, indicating more complex influence of TOM burial in the Yellow Sea. During the Early Holocene （7200-6000 cal yr BP）, the moderate TOM input revealed by the terrestrial proxy records may result from abundant land source supply by strong river transport despite the lack of transport via circulation system. The Mid-Holocene （6000-3000 cal yr BP） was characterized by decreased terrestrial biomarker contents. The balance between the decrease in land source supply and increase of transportation by the current system of the TOM resulted in the lower but stable contents of TOM. During the Late Holocene （3000 cal yr BP to present）, the TOM deposition in the South Yellow Sea increased as the current system was further enhanced and thus transported more TOM to the central South Yellow Sea, although the land supply of TOM was further reduced.

关键词： South Yellow Sea Holocene Biomarker Marine organic matter Terrestrial organic matter

Major Mid-Late Holocene Cooling in the East China Sea Revealed by an Alkenone Sea Surface Temperature Record

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Journal of Ocean University of China 2014年第6期13卷 935-940页

作者： ZHAO Meixun DING Ling XING Lei QIAO Shuqing yang zuosheng Key Laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of China Institute of Marine Organic Geochemistry Ocean University of China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration College of Marine Geoscience Ocean University of China

Although the mid-late Holocene cold and dry event about 4000years ago （the 4ka event） has been observed almost globally, it was most prominent in terrestrial climate proxies from the lower latitudes. Here we evaluate the oceanic response to this event in terms of a Holocene sea surface temperature （SST） record reconstructed using the U^7 index for Core B3 on the continen- tal shelf of the East China Sea. The record reveals a large temperature drop of about 5~C from the mid-Holocene （24.7~C at 5.6ka） to the 4ka event （19.2~C at 3.8ka）. This mid-late Holocene cooling period in Core B3 correlated with （i） decreases in the East Asia summer monsoon intensity and （ii） the transition period with increased E1 Nifio/Southern Oscillation activities in the Equatorial Pa- cific. Our SST record provides oceanic evidence for a more global nature of the mid-late Holocene climate change, which was most likely caused by a southward migration of the Intertropical Converge Zone in response to the decreasing summer solar insolation in the Northern Hemisphere. However, the large SST drop around Core B3 indicates that the mid-late Holocene cooling was regionally amplified by the initiation/strengthening of eddy circulation/cold front which caused upwelling and resulted in additional SST de- crease. Upwelling during the mid-late Holocene also enhanced with surface productivity in the East China Sea as reflected by higher alkenone content around Core B3.

关键词： sea surface temperature alkenone East China Sea 4 ka ITCZ