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Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science china Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1.& chen Ronghua2 1. State Key {1. of marine geology, tongji university, shanghai 200092, china 2. The Key {1. of Submarine Geoscience, State Oceanic Administration, Hangzhou 31.01., china State Key laboratory of {1. geology tongji university shanghai china The Key laboratory of Sub{1. Geoscience State Oceanic Administration Hangzhou china

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2) and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1.and Dansgaard-Oeschger1.vents, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1. c2, d, e1.and e2, respectively, corresponding to oxygen isotopic 2.0, 3.1. 3.3, 4.0, 5.1.and 5.3, are identified from Core B2-9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2 and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

Microfossils, carbonate lysocline and compensation depth in surface sediments of the northeastern South{1. Sea

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Acta Oceanologica Sinica 2003年第4期22卷 597-606页

作者： chen Ronghua1, Xu Jian2, Meng Yi3, Wang Dongjun1 liu Chuanlian2, Huang Baoqi2, Zhang Fuyuan1 1. Key laboratory of Submarine Geosciences of State Oceanic Administration, Hangzhou 310012, china 2. laboratory of marine geology, tongji university, shanghai 200092, china 3. Institute of Estuarine and Coastal Research, East china Normal university, shanghai 200062, china Key Lab Submarine Geosci State Ocean Adm Hangzhou 310012 Peoples R China tongji Univ Lab Marine Geol Shanghai 200092 Peoples R China E china Normal Univ Inst Estuarine & Coastal Res Shanghai 200062 Peoples R China

Based on the quantitative analyses of abundance of planktonic foraminifera, benthic foraminifera, calcareous nannofossils, the ratios of calcareous to siliceous microfossils, and the determination of carbonate contents in the surface sediments of the northeastern South{1. Sea, it has been found that the carbonate contents, the abundance of planktonic foraminifera and calcareous nannoplankton, and the ratio of calcareous microfossils decrease rapidly while the ratio of the benthic foraminifera to the total foraminiferal fauna, specific value of siliceous microfossils, and the percentage of the agglutinated tests in the benthic foraminiferal fauna increase with the water depth. The results indicate that the microfossils abundance and ratio, and the carbonate content are closely related to the carbonate lysocline and carbonate compensation depth (CCD) in the study area. In addition, the carbonate lysocline and the CCD are different between the southern and northern parts of the South{1. Sea. Both the lysocline and the CCD are deeper in the south with 2 600 and 3 600 m than in the north with 2 200 and 3 400 m, respectively.

关键词： microfossils carbonate lysocline depth carbonate compensation depth (CCD) surface sediments South china Sea (SCS)

Exploring Physical Indicators for Carbonate Contents in Deep Sea Sediments

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Journal of china {1. of Geosciences 2003年第4期14卷 300-305页

作者： Huang Wei liu Zhifei {1. Xiaoliang Wang Pinxian laboratory of marine geology, tongji university, shanghai200092 laboratory of {1. geology Tongji University Shanghai 200092

To determine carbonate contents of deep sea sediments using physical properties is an enjoyable and efficient paleoceanographic way, which has been processed successfully in many studies based on a low resolution, but rather than a high one. A series of mathematical methods including the least square method were used in this study to build multiple regression equations between color reflectance and carbonate content, and between magnetic susceptibility and carbonate content, based on the data of color reflectance and magnetic susceptibility collected via the ODP Leg 1.4 cruise, as well as measured carbonate contents. We found that percent carbonate estimated with diffuse reflectance is closer to the measured one than that estimated with magnetic susceptibility, and the multiple regression equation is varied in different sites.

关键词： carbonate color reflectance magnetic susceptibility South china Sea ODP Leg 1.4.

Siliceous microplankton fluxes and seasonal variations in the central South{1. Sea during 1.93-1.95: monsoon climate and ? Nino responses

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Chinese Science Bulletin 2000年第23期45卷 2168-2172页

作者： WANG Rujian, liN Jun, ZHENG lianfu, chen Ronghua & chen Jianfanglaboratory of marine geology of MOE, tongji university, shanghai 200092, china The Key laboratory of Submarine Geoscience, State Oceanic Administration, Hangzhou 31.01., china Correspondence should be addressed to Wang Rujian laboratory of {1. geology of MOE Tongji University Shanghai China The Key laboratory of Sub{1. Geoscience State Oceanic Administration Hangzhou China

Seasonal variations of radiolarian and diatom fluxes in the central South china Sea during 1.93-1.95 were overwhelmingly controlled by monsoon c{1.mate. Radiolarian and diatom increased obviously during the Northeast (from November to February) and Southwest (from June to September) monsoons and decreased during the periods between the monsoons. The change of circulation driven by the monsoons improved water exchange in the different areas that brought rich nutrient materials for the surface microplankton, thereby enhancing radiolarian and diatom fluxes. Variation of radiolarian flux coincided with organic carbon flux, surface primary and export productivities. High radiolarian flux corresponded to high surface primary productivity. Radiolarian and diatom fluxes raised abnormally during 1.94-1.95 could be attributed to the El Nino event during the period.

关键词： siliceous microplankton fluxes seasonal variations monsoon climate El Nino event central South china Sea.

Denitrification in Qi'ao Island coastal zone,the Zhujiang Estuary in china

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Acta Oceanologica Sinica 2009年第1期28卷 37-46页

作者： WANG Hu ZHOU Huaiyang PENG Xiaotong YANG Qunhui QIN Chaomei YIN Xijie chen Guangqian Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State Key laboratory. of {1. geology Tongji University Shanghai 200092 China Graduate university of Chinese Academy of Sciences Beijing 100049 China

Samples of sediments and the overlying water were collected in the Qi＇ao Island coastal zone,the Zhujiang（Pearl River） Estuary（ZE）.Denitrification rates,sediment oxygen demand（SOD）,and fluxes of inorganic nitrogen compounds were investigated with N2 flux method,using a self-designed continuous flow through and auto-sampling *** results indicate that the denitrification rates varied between 222 and 908 μmol/（m2·h） with an average of 499 μmol /（m2·h）.During incubation,the sediments absorbed dissolved oxygen in the overlying water with SOD ranging from 300 to 2 363 μmol/（m2·h）.The denitrification rates were highly correlated with the SOD（r2=0.77） regardless of the NO-3＋NO-2 concentrations in the overlying water,organic carbon contents in sediments and water temperature,suggesting that the SOD was probably the main environmental factor controlling the denitrification in the Qi＇ao Island coastal *** was a net flux of NO-3＋NO-2 into the sediments from the overlying *** NH＋4 flux from sediments into water as the result of mineralization was between 1..3 and 21..3 μmol/（m2·h）,which seems limited by both organic carbon content in sediment and dissolved oxygen concentration in the overlying water.

关键词： denitrification N2 flux SOD inorganic nitrogen compound Qi' ao Island coastal zone Zhu-jiang Estuary

SEDIMENT LOAD AND ITS INFLUENCE ON CHANNEL PROCESSES OF SOME LARGE RIVERS IN RUSSIA AND china

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International Journal of Sediment Research 2000年第3期 307-320页

作者： liU Shuguang,CHALOV R.S, WU Dandan, li congxian Postdoctor, Research Fellow, Key laboratory of marine geology, tongji university, shanghai 200092, china & Researcher, State Key laboratory of Estuarine and Coastal Research, shanghai 200062,china Professo

The sediment load, particle size distribution, and ratio between suspended and bed load components. are analyzed for some large rivers in Russia and china. The relationship is shown between the longitudinal changes in sediment load and the directions of vertical river channel deformation, i.e. river incision or sedimentation, which in turn are supported by results of analysis of long-term stage discharge curves. It seems that branching channels are common for the rivers, except where the sediment load is great (such as in the Yellow River). Conditions for forming different types of river channels are defined with the help of diagrams showing the water discharge-slope and slopesediment concentration relationships.

关键词： Sediment load Channel processes River pattern Russia river

福建九龙江和东屿地区全新世微型硅藻的初步研究

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海洋学报 2003年第6期25卷 89-98页

作者：高亚辉陈长平李扬王开发支崇远厦门大学生命科学学院福建厦门361005 同济大学海洋地质与地球物理系上海200092

利用透射电镜研究了九龙江口现代潮间带表层沉积物、九龙江地区中全新世剖面和东屿中-晚全新世剖面的微型硅藻(细胞大小为2～20μm)的组成和丰度.共计硅藻1.属26种(包括变种).对每个种的生态分布作了描述,并提供了相应的壳面电镜照片.Th... 详细信息

利用透射电镜研究了九龙江口现代潮间带表层沉积物、九龙江地区中全新世剖面和东屿中-晚全新世剖面的微型硅藻(细胞大小为2～20μm)的组成和丰度.共计硅藻1.属26种(包括变种).对每个种的生态分布作了描述,并提供了相应的壳面电镜照片.Thalassionemanitzschioides是九龙江口现代潮间带表层沉积物中的优势种;九龙江中全新世地层的优势种为Naviculaclimacospheniae,Thalassionemanitzschioides;东屿中-晚全新世地层中,Cyclotellastriata,Thalassionemanitzschioides是优势种.微型硅藻在各个样品中所占比例都相对较高,最高可达86.7%,表明微型硅藻在沉积硅藻中占有重要的地位.

关键词：微型硅藻透射电镜全新世九龙江东屿地区

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南海中部浮游有孔虫通量的季节变化

同济大学学报（自然科学版） 2000年第1期28卷 73-77页

作者：陈荣华翦知 郑玉龙陈建芳国家海洋局海底科学重点实验室浙江杭州310012 同济大学教育部海洋地质重点实验室上海200092

南海中部 1.993～ 1.995年连续两年的浅层和深层时间系列沉积物捕获器试验 ,揭示浮游有孔虫总通量以及Globigerinoidessacculifer,Globigerinoidesruber,Neogloboquadrinadutertrei,Globigerinitaglutinata等种的通量和相对百分数在东北季风和西南季风盛行期出现高值 ,而Globigerinabulloides,Pulleniatinaobliquiloculata和Globorotaliamenardii等种则仅在冬季东北季风盛行期出现高值 .此外 ,还发现浮游有孔虫属种的通量呈现出明显的年际变化 .

关键词：有孔虫通量季节变化沉积捕获器古海洋学南海

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模拟退火算法机理研究

同济大学学报（自然科学版） 2004年第6期32卷 802-805页

作者：陈华根吴健生王家林陈冰同济大学海洋地质教育部重点实验室上海200092

从机理上分析了采用Metropolis概率接受准则的重要性 ,认为按照该准则可以使模型跳出局部极小值 ,避免了落入局部极小点的可能 ,然后在退火计划的控制下模拟退火算法 ,最终可以找到最优解 ;深入分析了算法的退火计划和模型扰动 ,以及两... 详细信息

从机理上分析了采用Metropolis概率接受准则的重要性 ,认为按照该准则可以使模型跳出局部极小值 ,避免了落入局部极小点的可能 ,然后在退火计划的控制下模拟退火算法 ,最终可以找到最优解 ;深入分析了算法的退火计划和模型扰动 ,以及两者之间的配合的技巧 ,认为算法本身可以作进一步的改进 ;并提出了改进的思路。

关键词：模拟退火算法效率最优退火计划