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Chinese Science Bulletin 2001年第S1期46卷 45-51页

作者： WANG Lachun & ZHANG YongzhanDepartment, of Urban & Resource Sciences, nanjing university, nanjing 210093, china key laboratory of coast & island development of ministry of education of china, nanjing university, nanjing 210093, china 1. Department of Urban & Resource Sciences Nanjing University 210093 Nanjing China 2. key laboratory of coast & island development of ministry of education of china Nanjing University 210093 Nanjing China

Conduit flow is a special geomorphologic and hydrological phenomenon in karst area. Houzhai River drainage basin in Puding, Guizhou Province is a large-scale test field in the main and broad karst area in the southern part of china, where conduit flow is a general reserve and drainage system for groundwater. Based on the great deal of field investigation and indoor research work during the 1970s-1980s, pulse tests were done four times there during 1988-1991 in wet and dry seasons. It shows that water level at each observation site changes from 10 to 1800 mm, with the larger variation in upper stream and at karst windows than in lower reaches and at each exit along subterraneous rivers. The average flow velocity in conduit system is determined within 200-800 m/h, with the less change from flood to dry seasons, and it is higher in principal conduits and in upper stream area. Also, the reliable divided discharge ratio among each hydrological conduit of sunken system has been got. Thus, combined with

关键词： conduit flow karst pulse test Houzhai River.

江苏盐城自然保护区滨海湿地生态系统的特征与健康设计

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海洋学报 2003年第3期25卷 143-148页

作者：刘青松李杨帆朱晓东南京大学海岸与海岛开发教育部重点实验室江苏南京210093

1 引言本文所论及的滨海湿地指的是广义沿海滩涂湿地,不仅指全部潮间带,还包括潮上带和潮下带可供开发利用的部分,其作为新生的土地资源(有一定范围、面积),主要发育于潮滩—平原海岸与河流的三角洲地区。

关键词：自然保护区滨海湿地生态系统

Relationship between bed shear stress and suspended sediment concentration:annular flume experiments

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International Journal of Sediment Research 2011年第4期26卷 513-523页

作者： Yunwei WANG,Qian YU,and Shu GAO 1,2 Dr.,3 Prof.,ministry of education key laboratory for coast and island development,nanjing university, Hankou Road 22,210093 nanjing,china, [a] Dr. Ministry of Education Key Laboratory for Coast and Island Development Nanjing University Hankou Road 22 210093 Nanjing China [b] Dr. Ministry of Education Key Laboratory for Coast and Island Development Nanjing University Hankou Road 22 210093 Nanjing China [c] Prof. Ministry of Education Key Laboratory for Coast and Island Development Nanjing University Hankou Road 22 210093 Nanjing China

In this study,annular flume experiments were carried out,using the sediment samples collected from the lower part of the inter-tidal zone at Xiaoyangkou,Jiangsu coast,*** Ariathurai-Partheniades equation was used to determine the bed shear stress,by evaluating variations in the suspended sediment concentration within the water *** derived relation between the bed shear stress and suspended sediment concentration shows that,at various stages of seabed erosion, suspended sediment concentration increases rapidly when the flow velocity is increased,but the pattern of change in the bed shear stress does not follow *** low concentrations,bed shear stress initially increases markedly with increasing flow ***,when the concentration reaches an apparently critical level around 0.55 kg m"3,the rate of change in the bed shear stress abruptly slows down,or becomes almost constant,in response to further increases in the flow *** of experiments indicate that,from a critical level onward,suspended sediment concentration has a strong influence on the bed shear stress.

关键词： Bed shear stress Suspended sediment concentration Annular flume

Late Oligocene Sedimentary Hiatus in Deep Sea Area of South china Sea, Result of Calcareous Nannofossils from ODP Site 1148

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Journal of china university of Geosciences 2004年第1期15卷 69-74页

作者： Su Xin key laboratory of Lithospheric and Lithoprobing Technology, china university of Geosciences, ministry of education, Beijing 100083, china State Pilot laboratory of coast & island development, nanjing university, nanjing 210093, china key laboratory of Lithospheric and Lithoprobing Technology China University of Geosciences Ministry of Education Beijing 100083 China State Pilot laboratory of coast & island development Nanjing University Nanjing 210093 China

In order to determine the age of the sedimentary hiatus and its geological significance, a study of the calcareous nannofossil biostratigraphy was carried out. Detailed stratigraphical data of the Late Oligocene-Early Miocene diagnostic species thus obtained. The nannofossil zonation of this interval was subdivided and the Oligocene-Miocene boundary was further determined. Several last Late Oligocene events were recognized, indicating a long-term sedimentary hiatus in the uppermost Upper Oligocene. The time span of the hiatus was estimated for about 2.2 Ma, at least from 23.9 to 26.1 Ma. The lithological and geophysical data from Site 1148 indicate some abrupt sedimentary changes that occurred below and above the hiatus. This hiatus at Site 1148 was probably related to the tectonic change, a major ridge jump during the seafloor spreading in the Late Oligocene South china Sea.

关键词： sedimentary hiatus calcareous nannofossils Late Oligocene ODP Site 1148 South china Sea.

Delineating suspended sediment concentration patterns in surface waters of the Changjiang Estuary by remote sensing analysis

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Acta Oceanologica Sinica 2010年第4期29卷 38-47页

作者： LI Jing GAO Shu WANG Yaping ministry of education key laboratory for coast and island development Nanjing University Nanjing 210093 China

Three Landsat TM imageries （taken on 18 May 1987,4 August 1998 and 28 July 2007） were used as the data source to identify the spatial and temporal variations of the suspended sediment concentration （SSC） in surface waters of the Changjiang *** correction was carried out to determine the water-leaving reflectance using the FLAASH module.A regression equation between surveyed SSC and suspended sediment index was chosen to retrieve the SSC from the Landsat TM *** addition,tidal harmonic analysis was performed to calculate tidal conditions corresponding to the acquisition time of satellite *** results show that the SSC spatial patterns are similar to the in situ observation results,which show the highest SSC in the region of turbidity maximum zone in the Changjiang *** the period of 1987 to 2007,the SSC pattern is controlled mainly by tidal dynamic conditions and wind speeds,rather than sediment discharges from the river.

关键词： suspended sediment concentration Landsat TM image tidal conditions the Chang-jiang Estuary

Process-based modeling of morphodynamics of a tidal inlet system

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Acta Oceanologica Sinica 2010年第6期29卷 51-61页

作者： XIE Dongfeng GAO Shu PAN Cunhong Zhejiang Institute of Estuaries and Hydraulics Hangzhou 310020 China ministry of education key laboratory for coast and island development Nanjing UniversityNanjing 210093 China

The morphodynamic evolution of an idealized inlet system is investigated using a 2-D depthaveraged process-based model,incorporating the hydrodynamic equations,Englund-Hansen’s sediment transport formula and the mass conservation *** model has a fixed geometry,impermeable boundaries and uniform sediment grain size,and driven by shore-parallel tidal *** results show that the model reproduces major elements of the inlet system,i.e.,flood and ebb tidal deltas,inlet *** is reached after several years when the residual transport gradually decreases and eventually *** equilibrium,the flow field characteristics and morphological patterns agree with the schematized models proposed by O’Brien （1969） and Hayes （1980）.The modeled minimum cross-sectional entrance area of the tidal inlet system is comparable with that calculated with the statistical P-A relationship for tidal inlets along the East china Sea *** morphological evolution of the inlet system is controlled by a negative feedback between hydrodynamics,sediment transport and bathymetric *** evolution rates decrease exponentially with time,i.e.,the system develops rapidly at an early stage while it slows down at later *** changes in hydrodynamics occur in the system;for example,the flood velocity decreases while its duration increases,which weakens the flood domination *** formation of the multi-channel system in the tidal basin can be divided into two stages;at the first stage the flood delta is formed and the water depth is reduced,and at the second stage the flood is dissected by a number of tidal channels in which the water depth increases in response to tidal scour.

关键词： tidal inlet morphological evolution sediment dynamics numerical modeling

Invading cord grass vegetation changes analyzed from Landsat-TM imageries: a case study from the Wanggang area, Jiangsu coast, eastern china

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Acta Oceanologica Sinica 2010年第3期29卷 26-37页

作者： LI Jing GAO Shu WANG Yaping key laboratory of ministry of education for coastal and island development Nanjing University Nanjing 210093 China

Cord grass colonization on the Jiangsu coast, eastern china, modifies the native salt marshes in terms of ecosystem structure. The Landsat TM images from 1992 to 2003 were analyzed to identify salt-marsh vegetation distribution patterns and their changes over this coastal region, in order to evaluate the effects of the spreading of the artificially introduced halophyte Spartina. Supervised classification was performed using Bands 3, 4 and 5 in conjunction with in situ training samples, to derive the distribution pattern of the vegetation in the study area. Further, in order to identify the intertidal areas with different tidal elevations, a data treatment procedure was designed to combine regional water level data using harmonic analysis with the waterlines on the TM images extracted by density slice. The results show that：（1） the Spartina alterniflora area has been expanding towards the sea rapidly since it was introduced, especially at initial stages; （2） in the upper part of the inter-tidal zone, the local marsh plant Suaeda salsa and the exotic species Spartina anglica were present only near the sea dyke, occupying only a small part of the entire salt marsh, and the area of these two species has been reduced by land reclamation; （3） there has been a trend for Spartina alterniflora to become the dominant species in the salt marshes in the study area; and （4） the elevation of Spartina alterniflora’s seaward fringe was close to mean high water on neaps, and its landward boundary was slightly higher than mean high water. The salt marsh environment of the study area has been modified rapidly by the Spartina vegetation for the last 12 years.

关键词： tidal flats salt marshes remote sensing vegetation cover Jiangsu coast

Observations and analyses of floc size and floc settling velocity in coastal salt marsh of Luoyuan Bay, Fujian Province, china

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Acta Oceanologica Sinica 2010年第3期29卷 116-126页

作者： WANG Aijun YE Xiang CHEN Jian Open laboratory for coast and Ocean Environmental Geology Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China key laboratory of ministry of education for coast and island development Nanjing University Nanjing 210093 China

In coastal environments, fine-grain sediments often aggregate into large and porous flocs. ElectroMagnetic Current Meters （EMCM） and Laser In Situ Scattering and Transmissometry （LISST-ST） have been deployed within a Spartina alterniflora marsh of the Luoyuan Bay in Fujian Province, china, to measure the current velocity, the floc size and the settling velocity between 15 and 22 January 2008. During the observations, the near-bed water was collected in order to obtain the suspended sediment concentration （SSC） and constituent grain size. Data show that：（1） the nearbed current velocities vary from 0.1 to 5.6 cm/s in the central Spartina alterniflora marsh and 0.1–12.5 cm/s at the edge; （2） the SSCs vary from 47 to 188 mg/dm 3 . The mean grain size of constituent grains varies from 7.0 to 9.6 μm, and the mean floc sizes （MFS） vary from 30.4 to 69.4 μm. The relationship between the mean floc size and settling velocity can be described as： w s =ad b , in which w s is the floc settling velocity （mm/s）, a and b are coefficients. The floc settling velocity varies from 0.17 to 0.32 mm/s, with a mean value of 0.26 mm/s, and the floc settling velocity during the flood tide is higher than that during the ebb tide. The current velocity and the SSC are the main factors controlling the flocculation processes and the floc settling velocity.

关键词： Spartina alterniflora marsh current velocity suspended sediment concentration mean floc size floc settling velocity Luoyuan Bay

Spatial distribution of 10m firn temperature in the Antarctic Ice Sheet

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Science china Earth Sciences 2011年第5期54卷 655-666页

作者： WANG YeTang1,3 & HOU ShuGui2,3 1 Shandong Marine Fisheries Research Institute,Yantai 264006,china 2 MOE,key laboratory for coast and island development,School of Geographic and Oceanographic Sciences,nanjing university,nanjing 210093,china 3State key laboratory of Cryospheric Science,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,china 1. Shandong Marine Fisheries Research Institute Yantai 264006 China3. State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China2. MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

A database of Antarctic 10 m firn temperature was constructed using available borehole temperature measurements with data quality control to extend knowledge of Antarctic climate. Slopes from a high-resolution digital elevation model and the main ice divide were used to delineate main drainage sectors across Antarctica. In each drainage sector, a quantitative relationship between temperature and latitude, longitude and altitude was established using available tim temperature data. Quantitative relationships incorporating other factors affecting Antarctic air temperature such as atmospheric circulation and small-scale to- pography were used to derive a 10-km resolution grid map of surface temperature. The resulting temperature patterns presented a reasonable depiction of both large and small-scale variations in Antarctic 10 m firn temperature. This map is useful for many spatial variation studies, Antarctic ice sheet models, and comparison with satellite-derived temperature data and outputs of atmospheric general circulation models.

关键词： Antarctica 10 m firn temperature spatial distribution

Distribution characteristics of heavy metals in surface sediments and core sediments of the Shenzhen Bay in Guangdong Province,china

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Acta Oceanologica Sinica 2009年第6期28卷 53-60页

作者： ZUO Ping WANG Yaping MIN Fengyang CHENG Jun key laboratory of coast and island development Ministry of Education Nanjing UniversityNanjing 210093 China

The concentration of zinc, chromium, cadmium, nickel, lead and copper was measured on both surface sediments and core sediments in the Shenzhen Bay. The average contents of all metals have exceeded the background values in the coastal zone of Guangdong Province. Cadmium is a heavy pollution matter which indicates a strong pollution level according to the ecological risk coefficient method. The ecological risk index of the whole area is 299 which belongs to middle and strong level. The area with strong pollution level is the near shore area closing to the inside of Shenzhen Bay, Shakou area is in the middle level while the weak pollution level occurs in Shenzhenhe Estuary according to ecological risk index. The four sediment cores can be divided into two parts based on lead-210 dating, sediments size analysis and economic development period in surrounding areas since 1950 with strong human intervention. The sediment size, deposition rate and human activities have positive relationship with the contents of heavy metals which directly impact the pollution level of heavy metals in sediments in Shenzhen Bay.

关键词： surface sediments core sediments distribution characteristics pollution assessments Shenzhen Bay in Guangdong Province