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Exploring cyclic changes of the ocean carbon reservoir

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Chinese Science Bulletin 2003年第23期48卷 2536-2548页

作者： WANG Pinxian, TIAN Jun, CHENG Xinrong, LIU Quanlian & XU Jian Key laboratory of marine geology, Ministry of Education, {3. Uni-versity,{4., china Key laboratory of marine geology Ministry of Education Tongji University

A 5-Ma record from ODP Site 114. has re-vealed the long-term cycles of 4.0—500 ka in the carbon isotope variations. The periodicity is correlatable all over the global ocean and hence indicative of low-frequency changes in the ocean carbon reservoir. As the same periodicity is also found in carbonate and eolian dust records in the tropical ocean, it may have been caused by such low-latitude proc-esses like monsoon. According to the Quaternary records from Site 114. and elsewhere, major ice-sheet expansion and major transition in glacial cyclicity (such as the Mid-Brunhes Event and the Mid-Pleistocene Revolution ) were all pre-ceded by reorganization in the ocean carbon reservoir ex-pressed as an episode of carbon isotope maximum (d 13.max), implying the role of carbon cycling in modulating the glacial periodicity. The Quaternary glacial cycles, therefore, should no more be ascribed to the physical response to insolation changes at the Northern Hemisphere high latitudes alone; rather, they have been driven by the 揹ouble forcing? a combination of processes at both high and low latitudes, and of processes in both physical (ice-sheet) and biogeochemical (carbon cycling) realms. As the Earth is now passing through a new carbon isotope maximum, it is of vital impor-tance to understand the cyclic variations in the ocean carbon reservoir and its climate impact. The Pre-Quaternary varia-tions in carbon and oxygen isotopes are characterized by their co-variations at the 4.0-ka eccentricity band, but the response of d 13. and d 18O to orbital forcing in the Quater-nary became diverged with the growth of the Arctic ice-sheet. The present paper is the second summary report of ODP Leg 184.to the South china Sea.

关键词：海洋 ODP 海洋钻探工程碳循环南中国海地层学

Ancient Changjiang channel system in the East china Sea continental shelf during the last glaciation

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Science china Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3. YUE Shuhong4. YANG Wenda5 & HAN Xibin1 1. College of marine Geo-science, Ocean University of china, Qingdao 266003. china 2. Shandong Key laboratory of Sea Floor Resource and Exploration Technique, Qingdao 266003. china 3. Qingdao Institute of marine geology, Qingdao 266071, china 4. College of marine Environment, Ocean University of china, Qingdao 266003. china 5. First Survey Team of marine geology, shanghai Bureau of Petroleum, shanghai 201208, china 1. College of marine Geo-science Ocean University of China 266003 Qingdao China 2. Shandong Key laboratory of Sea Floor Resource and Exploration Technique 266003 Qingdao China 3. Qingdao Institute of marine geology 266071 Qingdao China 4. College of marine Environment Ocean University of China 266003 Qingdao China 5. First Survey Team of marine geology Shanghai Bureau of Petroleum 201208 Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East china Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

Forcing mechanism of the Pleistocene east Asian monsoon variations in a phase perspective

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Science china Earth Sciences 2005年第10期48卷 1708-1717页

作者： TIAN Jun1,2, WANG Pinxian1, CHENG Xinrong1, WANG Rujian1 & SUN Xiangjun1,3.1. State Key laboratory of marine geology, {3. University,{4., china 2. Institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china 3. Institute of Botany, Chinese Academy of Sciences, Beijing 100093. china State Key laboratory of marine geology {3. University {4. china Institute of geology and Geophysics Chinese Academy of Sciences Beijing china Institute of Botany Chinese Academy of Sciences Beijing china

The deep sea records from the ODP Sites 114. and 114. in the northern and southern South china Sea (SCS), including foraminiferal δ 18O and δ 13., Opal% and pollen percentage, reveal that the variations of the east Asian monsoon have been closely correlated with the variations of the Earth’s orbital parameters (eccentricity, obliquity and precession) and the global ice volume on orbital scale. All the monsoonal proxies show strong 100 ka, 4. ka and 23.ka cycles. Although G. ruber δ 13. of Site 114. is coherent with the ETP (ETP= normalized (eccentricity + obliquity-precession) at eccentricity, obliquity and precession bands, most of the coherent relationship focuses on the precession band, and the other monsoonal proxies are coherent with the ETP only at the precession band, which indicate that precession dominates the Pleistocene tropical climate changes. The phase relationship of the monsoonal proxies with the foraminiferal δ 18O implies that the global ice volume changes have played a significant role in modulating the east Asian monsoon climate, at least dominating the winter monsoon. This forcing mechanism of the east Asian monsoon is apparently different from that of the Indian ocean mon-soon. The variations of the east Asian monsoon at the precession band, at least that of the winter monsoon, have been controlled not only by the sensible heating but also by the latent heating of the surface water in the South china Sea.

关键词： South china Sea, ODP, east Asian monsoon, orbital forcing, global ice volume.

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 laboratory of marine geology, {3. University,{4., china 2. The Key laboratory of Submarine Geoscience, State Oceanic Administration, Hangzhou 3.0012, china State Key laboratory of marine geology {3. University {4. china The Key laboratory of Submarine 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-Oeschger1events, 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.

Stage characteristics for the development of late Quaternary paleosols in the Yangtze Delta area

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Chinese Science Bulletin 1999年第9期44卷 857-860页

作者： CHEN Qingqiang and LI Congxianlaboratory of marine geology , {3. University ,{4., china Guangzhou Institute of Geochemistry , Chinese Academy of Sciences , Guangzhou 51064., china laboratory of marine geology Tongji University Shanghai China Guangzhou Institue of Geochemistry Chinese Academy of Sciences Guangzhou China

The late Quaternary paleosols in the Yangtze Delta area developed in the period of 25 000—12 000 aBP. Phytolith ratios (value A) of contents of fan, square and rectangle types indicaring the warm and humid climate to those of bar, hat and point types indicating cold and dry climates decrease upwards overall on profiles of the paleosols, suggesting that the climates turned from warm and humid to cold and dry. So, the paleosols developed mainly during the regression before the last glacial maximum. Changes of value A indicate no trend of warming, suggesting that the transgression was rapid after the last glacial maximum. The development of the paleosols exhibited obvious stages, which were controlled remarkably by transgression and regression: Ⅰ. Period of alternation of deposition and pedogenesis, which was from the occurrence of regresson before the last glacial maximum to the time when sea levels fell close to the lowest;Ⅱ. Exposure period with continual pedogenesis, which was terminated when the

关键词： paleosol phytolith development processes late Quaternary Yangtze Delta.

Palynological record during the Pleistocene (between 1.05 Ma and 0.3. Ma) from ODP114., northern South china Sea

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Science china Earth Sciences 2004年第1期47卷 30-36页

作者： HUANG Fei & SUN XiangjunInstitute of geology and Paleontology, Chinese Academy of Sciences, Nanjing 210008, china Institute of Botany, Chinese Academy of Sciences, Beijing 100093. china Key {3. of {4. geology, Ministry of Education, tongji University, shanghai 200092, china Correspondence should be addressed to Huang Fei 1. Institute of geology and Paleontology Chinese Academy of Sciences 210008 Nanjing China 2. Institute of Botany Chinese Academy of Sciences 100093 Beijing China 3. Key laboratory of marine geology Ministry of Education Tongji University 200092 Shanghai China

This paper presents the pollen record from the lower section of ODP114. (depth 501.3.225.7 m, ca. 1.05-0.3. Ma). Two pollen zones (PA and PB) and eleven pollen subzones are recognized. Within zone PB, the 11 pollen subzones (PB21-11) are defined according to the pine, fern and herb variations, and are equivalent to the marine isotope stages 21-11 (MISs 21-11). The interglacial periods are typified by an increase in pine pollen and fern spores, and a decrease in herbaceous pollen, while the patterning during the glacial periods is just the opposite. During the interglacial periods, pollen assemblages were dominated by pine similar to those of the present day, suggesting that the paleoenvironment of the interglacial periods was similar to that of the present day, whereas the glacial periods are marked by an increase in herbaceous pollen, mainly Gramineae and Cyperaceae, indicating that grassland covered the exposed continental shelf when sea level declined. Increased Artemisia percentages and the highest pine influx during MIS12 may result from a stronger winter monsoon.

关键词： pollen record, Pleistocene, ODP114., northern South china Sea.

Microfossils, carbonate lysocline and compensation depth in surface sediments of the northeastern South china 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 3.0012, 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 china 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 china 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 3.4.0 m, respectively.

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

Lower Boundary of the marine Pleistocene in Northern Shelf of the South china Sea

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 427-439,460页

作者： Wang Pinxian Xia Lunyu Wang Lujiang Cheng Xinrong Department of marine geology, tongji University,{3.,{4. Research Institute, Nanhai West Oil Corporation, Zhanjiang, Guangdong 524.57, china 1 1) Department of marine geology Tongji University Shanghai 200092 China 2 2) Research Institute Nanhai West Oil Corporation Zhanjiang Guangdong 524057 China

A marine stratigraphic sequence across the Pliocene / Pleistocene boundary has been found in the north-ern continental shelf of the South china Sea. The marine Quaternary deposits in the Yinggehai Basin may ex-ceed 2,000 m in thickness, probably providing the best section for studying the lower boundary of the marinePleistocene in South china. The vertical succession with planktonic foraminifers and nannofossils revealed inboreholes in the basin has been well correlated with that in the international stratotype section of thePliocene / Pleistocene boundary at Vrica, Italy, resulting in the acquirement of a biostratigraphic boundary at1.64.Ma. This boundary, however, does not coincide with any prominent lithological palaeoenvironmentalchanges in the study area and can hardly be used in geological practice. There are, in contrast, significantchanges at the level of LAD of Globorotalia multicamerata sensu lato located below the above-mentionedboundary. The percentage of planktonic foraminifers in the total population and preservation of foraminiferaltests display great changes at this level corresponding to a clear onlap on the seismic profiles and indicating adepositional hiatus at ca. 2.0-2.5 Ma. Since the level can be widely traced in the Pearl River Mouth Basin andthe Beibu Gulf Basin and well corresponds with the marked depositional environmental changes recorded inthe west Pacific and other regions, it is recommended that the Plio / Pleistocene boundary be drawn at the levelof Gr. multicamerata sensu lato LAD, roughly concurrent with the Gauss / Matuyama turn.

关键词： Lower Boundary of the marine Pleistocene in Northern Shelf of the South china Sea

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

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Science china Earth Sciences 2011年第4期54卷 473-480页

作者： FANG JiaSong 1,2 &ZHANG Li 3.1 State Key laboratory of marine geology,{3. University,{4. 200092,china 2 College of Natural and Computational Sciences,Hawaii Pacific University,Kaneohe,HI 9674.,USA 3.tate Key laboratory of Geological Processes and Mineral Resources,Faculty of Earth Sciences,china University of Geosciences,Wuhan 4.0074.china 1. State Key laboratory of marine geology Tongji University Shanghai 200092 China2. College of Natural and Computational Sciences Hawaii Pacific University Kaneohe HI 96744 USA3. State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean *** oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine *** application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem *** we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.

关键词： microbial oceanography genomics metagenomics genes biomass bacteria archaea eukarya phylogeny physiology metabolism ecology biogeochemistry microbiology ecosystem function