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Chinese Journal of Oceanology and Limnology 2017年第1期35卷 39-60页

作者： YANG Xianping SOKOLETSKY Leomd WEI Xiaodao SHEN Fang state key laboratory of estuarine and coastal research East China Normal University Shanghai 200062 China

The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration(SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra R_(rs)(λ) after atmospheric correction; 2) an estimation of R_(rs)(λ) from the radiometric signals above the air-water surface; and 3) an estimation of SSC from R_(rs)(λ). Six different models for radiometric R_(rs)(λ) determination and 28 models for SSC versus R_(rs)(λ) are analyzed based on the field observations made in the Changjiang River estuary and its adjacent coastal area. The SSC images based on the above-mentioned analysis are generated for the area.

关键词： ocean optics turbid estuarine and coastal waters remote-sensing reflectance suspended sediment concentration atmospheric correction

Impacts of wind stress on saltwater intrusion in the Yangtze Estuary

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Science China Earth Sciences 2012年第7期55卷 1178-1192页

作者： LI Lu ZHU JianRong WU Hui state key laboratory of estuarine and coastal research East China Normal UniversityShanghai 200062China

The observation at the Chongxi gauging station indicated the salinity of saltwater spilling over from the North Branch to the South Branch increased abnormally from November 10 to 12 in 2009 (during neap tide) and from February 11 to 12 in 2010 (during moderate tide).We found for the first time that the strong northerly wind was responsible for the above abnormal salinity *** studies indicated that the saltwater intrusion in the Yangtze Estuary is influenced mainly by the river discharge,the tide,and the wind stress,but the impacts of variations of wind speed and direction on it have not been *** this study the impacts of wind stress on the saltwater intrusion were numerically simulated and the associated mechanisms were *** model results were consistent with the observed data obtained at six gauging stations during February and March in 2007 and four gauging stations in March 2008,and the abnormal salinity risings were well ***,if the wind speed is reduced by half,the salinity there will be significantly *** by the monthly mean river discharge of 11000 m 3 /s and northerly wind of 5 m/s from January to February,the model simulated the temporal and spatial variation of saltwater *** wind-driven circulation,as well as the net water and salt fluxes from the North Branch into the South Branch,was calculated and analyzed in the cases of different wind speeds and *** results indicated that the intensity of the saltwater intrusion in the Yangtze Estuary is significantly influenced by the wind speeds and directions.

关键词： Yangtze Estuary saltwater intrusion wind-driven circulation salt flux numerical simulation

Rule-and PSO Algorithm-based Dynamic Spatial Rescheduling Method for Hull Curved Block Construction

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 594-605页

作者： ZHANG Zhiying GU Jiayu XU Chen LI Zhen School of Mechanical Engineering Tongji University state key laboratory of estuarine and coastal research East China Normal University

Due to no effective rescheduling method in hull curved block construction planning, existing scheduling planning can’t be applied in practical production effectively. Two-dimensional layout and dynamic attributes of block construction planning are considered to develop a spatial rescheduling method, which is based on the spatial points searching rule and the particle swarm optimization(PSO) algorithm. A dynamic spatial rescheduling method is proposed to solve the manufacturing problem of rush-order blocks. Through spatial rescheduling, the rescheduling start time, the current processing information set and rescheduling blocks set can be obtained automatically. By using and updating the data of these sets, the rescheduling method combines the PSO algorithm with the spatial points searching rule to determine the rescheduling start time and layout of the blocks. Three types of dynamic events, including rush-order block delay, existing block delay and existing block position changes, are used to address problems with different function goals by setting different function weights. Finally, simulations based on three types of rush-order block events are performed to validate this method, including single rush-order block, multi rush-order blocks at the same time and multi rush-order blocks at different times. The simulation results demonstrate that this method can solve the rush-order block problems in hull block construction and reduce the interference to the existing manufacturing schedule. The proposed research provides a new rescheduling method and helps instruct scheduler to make production planning in hull block construction.

关键词： spatial scheduling rush-order block event particle swarm optimization dynamic rescheduling

Changes over flood season in turbidity maximum zone in a mountainous macrotidal estuary from 1986 to 2020

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Journal of Geographical Sciences 2023年第5期33卷 980-998页

作者： LIU Ruiqing CHENG Heqin TENG Lizhi FAN Heshan state key laboratory of estuarine and coastal research East China Normal UniversityShanghai200241China

The construction of channel regulation projects,reservoirs,and other human activities have led to significant changes in channel geometry and hydrodynamic conditions in mountainous macrotidal ***,their impact on the long-term evolution of the turbidity maximum zone(TMZ)in these estuaries is still ***,the Minjiang Estuary(ME)was selected as the study area and using the Gabor filter and surface suspended sediment concentration(SSSC)data retrieved from GF PMS/WFV and Landsat-TM/ETM+/OLI images in the flood season from 1986 to 2020,the flow direction of Chuanshi Waterway,the spatiotemporal evolution characteristics of TMZ in the ME,and the influence of human activities on these were *** results indicate that during flood tides in the past 35 years,the TMZ was mainly distributed in sections from the Changmen to the Chuanshi and Meihua *** construction of the Shuikou Reservoir caused the SSSC to decrease by 65 mg/L at the Chuanshi Tidal Gauge Station in the *** TMZ in the ME waterway channel notably migrated toward the sea due to the waterway regulation project,with the landward and seaward boundaries moving by 2.5 km and 3 km seaward,*** main distribution area moved from Jinpaimen to the section from Chuanshi Waterway to the mouth of the *** variation characteristics were basically consistent with the annual average TMZ in the flood *** the interactions between nature and human interventions,the flow regime of the ME tended to converge in the flood ***,human activities have significantly impacted the long-term evolution of the TMZ in the ME.

关键词： turbidity maximum zone spatiotemporal evolution flow regime remote sensing large-scale engineering Minjiang Estuary

Microseismic observations reveal that internal waves intensify seabed methane release

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Science China Earth Sciences 2024年第10期67卷 3186-3203页

作者： Zhaoyang TIAN Yonggang JIA Junjiang ZHU Tian CHEN Hui WANG Chunsheng JI Chengyu LIU Longyu LU Manchao HE Shandong Provincial key laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Lab of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Guangzhou Marine Geological Survey China Geological SurveyGuangzhou 511458China Shandong Earthquake Agency Jinan 250014China state key laboratory for Tunnel Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Internal waves transport material and energy from the upper water column to the deep ocean, disturbing seabed sediments and resulting in phenomena such as seabed erosion and changes in topography. On the northern slope of the South China Sea and in many coastal margins worldwide, the zones with internal wave action closely overlap with areas where natural gas hydrates are present. However, due to significant differences in the spatial and temporal scales, understanding the influence of internal waves on methane releases from deep seabeds is challenging. In this study, in situ observations of seabed microseismicity and internal waves are conducted at water depths of 655 meters and 1450 meters in the Pearl River Canyon of the South China Sea. The microseismicity caused by internal waves and seabed methane releases is identified, and a method to establish the correlation between internal waves and seabed methane releases through the use of microseismic recordings is proposed, aiming to obtain direct observational evidence of internal waves intensifying seabed methane releases. The results show that internal waves and seabed methane releases generate significant microseismic signals, indicating the continuous influence of internal waves on the deep seabed of the northern slope of the South China Sea and revealing active methane release phenomena on the seabed. At both long and short time scales, internal waves increase the frequency of seabed methane releases by 4.2 times and 2.4 times, respectively, while also enhancing the intensity of these releases. These changes are influenced by the alterations in seabed flow velocity, pressure, and temperature that are induced by internal wave activities. This study emphasizes that microseismic signals are effective carriers of information for multiscale geological processes on seabeds and suggests that internal waves exacerbate marine geological hazards and contribute to global climate change by intensifying seabed methane relea

关键词： Internal waves Seabed methane release Microseismic observation Ocean bottom seismometer Northern slope of the South China Sea

Flocculation process of fine-grained sediments by the combined effect of salinity and humus in the Changjiang Estuary

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Acta Oceanologica Sinica 2007年第1期26卷 140-149页

作者： LIU Qizhen LI Jiufa DAI Zhijun LI Daoji state key laboratory of estuarine and coastal research East China Normal University Shanghai 200062 China

For the great amount of organic compounds and the variation of salinity in the Changjiang Estuary, the study on the flocculation process of fine-grained sediments by the combined effect of salinity and humus in the high-turbid system is of critical significance for the understanding of the mechanism of the formation of the turbidity maximum （TM） . For the great amount of organic compounds and the variation of salinity in the Changjiang Estuary, the study on the flocculation process of fine-grained sediments by the combined effect of salinity and humus in the high-turbid system is of critical significance for the understanding of the mechanism of the formation of the turbidity maximum （TM） . The effects of salinity and humus on the fine-grained sediments have been analyzed through the synthetic study of the aspects of flocculation/coagulation power （ F）, diameter （D） and zeta potential （Z）. And the microcosmic configuration of the flocs has been analyzed by using a scan electron microscope and Fourier Transform Infrared Spectrometry. The results show that：（ 1 ） with the increase of salinity, F and D become greater and Z becomes smaller, and with the increase of the concentration of humus, F becomes smaller, but D and Z become greater; （2） the microcosmic configuration of the flocculation shows that humus packs on the fine sediments in the form of salt, and the flocculation model of C - P - OM （C stands for clay; P cations; OM organic materials） can successfully demonstrate the mechanism of the formation of the finegrained sediments in the high-turbid area of the Changjiang Estuary.

关键词： Changjiang Estuary fine-grained sediment floceulation salinity

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

Distribution of chlorophyll-a off the Changjiang River and its dynamic cause interpretation

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Science China Earth Sciences 2005年第7期48卷 950-956页

作者： ZHU Jianrong state key laboratory of estuarine and coastal research East China Normal University Shanghai 200062 China

An interdisciplinary comprehensive survey was conducted in August 2000 with the modern measurement instruments off the Changjiang River. The analysis of the observation data shows that there exist two sources of phytoplankton blooms off the Changjiang River. The one with wider spatial extent and stronger intensity appears in the surface plume due to photosyn- thesis produced by the eutrophication brought by a huge amount of nutrient load via the Chang- jiang River and well light penetration because of lower turbidity seawater. Photosynthesis pro- duces chlorophyll-a (Chl-a), meanwhile releases oxygen and absorbs carbon dioxide, so the high Chl-a concentration distribution corresponds to the distribution of high dissolved oxygen and pH. The other with smaller spatial extent and weaker intensity exists in the thermocline in the Taiwan Warm Current (TWC), but the high Chl-a concentration does not correspond to the high dissolved oxygen and pH, which may be a result of long distance advection by the TWC. The eutrophica- tion associated with the huge amount of nutrient flowing into the sea via the Changjiang River is the main cause of the red tide bloom in the area off the Changjiang River, the red tide that oc- curred along the Fujian and Zhejiang coast can influence the area off the Changjiang River pos- sibly via the TWC. The distributions of current simulated by a three-dimension numerical model support the above conclusion.

关键词： area off the Changjiang River field survey red tide eutrophication Taiwan Warm Current.

A three-dimensional mathematical transport model for suspended sediment by waves and currents

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Progress in Natural Science:Materials International 2001年第4期11卷 27-33页

作者：丁平兴孔亚珍朱首贤朱建荣 China East China Normal University Shanghai 200062 state key laboratory of estuarine and coastal research

Based on the equations of momentum and continuity, a general three-dimensional transport model for suspended sediment by waves and currents is developed by respectively decomposing the instantaneous velocities and concentrations into three different time-scale components. The model is composed of two submodels. One is a three-dimensional flow field submodel including the influence of waves, and the other is a three-dimensional diffusion submodel for suspended sediment due to waves and currents. The purpose of this study .is to provide a theoretical model for further investigating sediment transport by waves and currents in estuarial and coastal areas.

关键词： estuary and coast three-dimensional model suspended sediment transport.

Harmonious Development of Utilization and Protection of Tidal Flats and Wetlands-A Case Study in Shanghai Area

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China Ocean Engineering 2008年第4期22卷 649-662页

作者：陈吉余程和琴戴志军 Doeke EISMA state key laboratory of estuarine and coastal research East China Normal University Royal Netherlands Institute for Sea research

Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain＇able exploitation of offshore resources in Shanghai area.

关键词： Shanghai area harmarious development utilization protection tidal fiat wetland