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Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

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chinese Science Bulletin 2003年第B06期48卷 37-41页

作者： GE Shulan~(1,2,3., SHI Xuefa~1 & HAN Yibing~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography, State Oceanic Administration. qingdao 266061. china 2. institute of Geology and Geophysics, chinese academy of Sciences, Beijing 100029. china 3. Graduate School. chinese academy of Sciences, Beijing 10003.. china 1. Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 172 surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assemblages in the continental sea, which indicates different sediment origins. With the 3. μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

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

Studies on the regional feature of organic carbon in sediments off the Huanghe River Estuary waters

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Acta Oceanologica Sinica 2004年第1期23卷 129-134页

作者： YUAN Huamao1, 2, LIU Zhigang3. SONG Jinming1, L Xiaoxia1, 2 LI Xuegang1, 2, LI Ning1, 2, ZHAN Tianrong1, 21. MEES, institute of oceanology, chinese {3. of Sciences, qingdao 266071, china2. Graduate School of the chinese {3. of Sciences, Beijing 10003., china3. Zhoushan Marine Eco-environmental Monitoring Station of Zhejiang Province, Zhoushan 3.6004, china chinese Acad Sci Inst Oceanol MEES Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Zhoushan Marine Ecoenvironm Monitoring Stn Zhoushan 316004 Peoples R China

Organic carbon (OC) in definitely small area sediments(according to marine dimension)off the Huanghe River Estuary is investigated in order to evaluate the feature of regional difference of physical and chemical properties in marginal sea *** distributions of OC in sediments with natural grain size and the relationship with the pH,Eh ,Es and Fe3./Fe2+ are *** addition,OC decomposition rates in surfacial/subsurfacial sediments are *** concentrations range from 0.26% to 1.8%(wt)in the study area. Significant differences in OC content and in horizontal distribution as well as various trends in surfacial /subsurfacial sediments exhibit the feature of regional difference remarkably in marginal sea sediments. The complicated distribution of OC in surface sediments is due to the influence of bacterial activity and abundance, bioturbation of benthos and physical disturbance. The OC decomposition rate constant in surfacial /subsurfacial sediments ranges from 0.009 7 to 0.076 a-1 and the relatively high values may be mainly related to bacteria that are mainly responsible for OC mineralization;meio-and macrofauna affect OC degradation both directly, through feeding on it, and indirectly through bioturbation and at the same time coarse sediments are also disadvantageous to OC *** almost all the middle and bottom sediments the contents of OC decrease with the increase of deposition depth, which indicates that mineralization of OC in the middle and bottom sediments has occurred via processes like SO reduction and Fe-oxide reduction.

关键词： regional feature organic carbon sediments Huanghe River Estuary

Spatial and temporal variations in pH and total alkalinity at the beginning of the rainy season in the Changjiang Estuary, china

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Acta Oceanologica Sinica 2005年第5期 72-81页

作者： GAO Xuelu1, 2, 3. SONG Jinming1*, LI Xuegang1, YUAN Huamao1, LI Ning1, 3.. institute of oceanology, chinese {3. of Sciences, qingdao 266071, china2. South china Sea institute of oceanology, chinese {3. of Sciences, Guangzhou 5103.1, china3. Graduate School of chinese {3. of Sciences, Beijing 10003., china

The results of field observation carried out in May 2003.were used to examine pH and total alkalinity behaviors in the Changjiang Estuary. It was showed that pH and total alkalinity took on clear spatial variations in values with the minima in the low salinity region. Like salinity, transect distributions of pH and total alkalinity (TA) in a downriver direction had a sharp gradient each. These gradients appeared in such a sequence that the TA gradient was earlier than salinity and pH gradients, and the salinity gradient was earlier than the pH gradient. These distribution characteristics seemed to be strongly influenced by the mixing process of freshwater and seawater, for both pH and total alkalinity had significant linear relationships with salinity and temperature. For pH, phytoplankton activities also had a significant impact upon its spatial distribution. During a period of 48 h, pH and total alkalinity changed within wide ranges for every layer of the two anchor stations, namely, Stas 13.and 20, which were located at the mixed water mass and seawater mass, respectively. For both Stas 13.and 20, pH and TA fluctuation of every layer could be very wide during a 4 h period. As a whole, the data of the two anchor stations showed that neither variations in salinity and temperature nor phytoplankton activities were the main factors strongly influencing the total alkalinity temporal variability on a small time scale. The data of Sta. 20 implied that both salinity variation and phytoplankton activities had a significant influence on pH temporal variability, but the same conclusion could not be drawn from the data of Sta. 13.

关键词： Changjiang Estuary pH total alkalinity spatial and temporal variations

Benthic foraminifera and bottom water evolution in themiddle-southern Okinawa Trough during the last 18 ka

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Science china Earth Sciences 2005年第6期48卷 805-814页

作者： LI Tiegang1, XIANG Rong1,2, SUN Rongtao1 & CAO Qiyuan1 1. institute of oceanology, chinese {3. of Sciences, qingdao 266071, china 2. College of Geosciences, Ocean University of china, qingdao 266003. china Correspondence should be addressed to Li Tiegang 1. institute of oceanology Chinese Academy of Sciences 266071 Qingdao China 2. College of Geosciences Ocean University of China 266003 Qingdao China

A piston sediment core E017 from the middle-southern Okinawa Trough was investigated. A preliminary study of the deep-water evolution since 18 cal. ka BP was performed basedon the quantitative census data of benthic foraminiferal fauna, together with planktonic foraminiferal oxygen and carbon isotope, AMS14C dating, and the previous results achieved in thesouthern Okinawa Trough. The result shows that the benthic fauna was dominated by Buliminaaculeata (d′Orbigny), Uvigerina peregrina (Cushman), Hispid Uvigerina and Uvigerina dirupta(Todd) during the glaciation-deglaciation before 9.2 cal. ka BP, while Epistominella exigua(Brady), Pullenia bulloides (d′Orbigny), Cibicidoides hyalina (Hofker), Sphaeroidina bulloides(d’Orbigny) and Globocassidulina subglobosa (Brady) predominated the fauna in the post-glaciaperiod after 9.2 cal. ka BP. The benthic foraminifera accumulation rate (BFAR), paleoproductivityestimates and benthic foraminiferal assemblage conformably indicate that surface water paleoproductivity and organic matter flux during the glaciation-deglaciation were higher than those othe post-glacial period in the middle-southern Okinawa Trough, and gradually enhanced from thesouthern to the central Okinawa Trough during the glaciation-deglaciation, which could becaused by the discrepancy of the terrigenous nutrients supply. High abundances of E. exigua, anindicator of pulsed organic matter input, after 9.2 cal. ka BP may indicate that the intensity oseasonally riverine pulsed flux during the post-glacial period was stronger than that of the glaciation-deglaciation period, and the seasonal influx in the central trough might be stronger than inthe south. The temporal distributions of the typical species indicating bottom water oxygen content and ventilation condition show that the ventilation of the bottom water during the post-glaciaperiod is more active than the glaciation-deglaciation, which reflects that the evolution of the intermediate and deep waters of the n

关键词： benthic foraminifera, the Okinawa Trough, deep-water evolution.

Estimation of water volume transports through the main straits of the East china Sea

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Acta Oceanologica Sinica 1991年第1期10卷 1-13页

作者： Zhao Baoren and Fang Guohong institute of oceanology, Academia Sinica, qingdao, {3., china

The structure of current speed and the variability of volume transports of the Kuroshio in the Tokara-kaikyo and Osumi-kaikyo are discussed on the basis of data of KER in the period from 1977 to 1984. The average geostrophic transport through these two straits is estimated to be 24. 5×106 m3.s and only 1/12 of the transport is through the Osumi-kaiky5. Countercurrents on both sides of the Kuroshio trunk are observed in the Tokara-kaikyo. Calculation indicates that the average geostrophic current speed is less than the GEK current speed, systematically. On the basis of the current measurements, the northward transports through the Taiwan Strait in winter and summer are estimated to be 1. 05×106and 3. 16×106m3.s, respectively. From Chu's data (1976) the average transport of the Kuroshio flowing into the East china Sea passing through the passage east of Taiwan is about 29. 3.106m3.s. From Miita and Ogawa's data (1984) the average transport through the Tsushima-kaikyo is 3. 6×106m3.s. Thus the volume transports through the above four straits are roughly in balance, the total outflowing transport is slightly larger than the total inflowing transport. The possible reasons resulting in the difference of transports are also discussed.

关键词： Estimation of water volume transports through the main straits of the East china Sea GEK

Nd isotope as the tracer of seawater evolution of early Miocene in the eastern Pacific Ocean

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chinese Science Bulletin 2003年第B06期48卷 106-110页

作者： LIU Jihua~(1,2,3., CHEN Lirong~1, WANG Yingxi~4 & HAN Jianxiu~5 1. institute of oceanology, chinese Acadcmy of ences,{3.. china 2. Key Lab of Marine Sedimentology and Environmental Geology, First institute of Oceanograpgy, State Oceanic Administration, qingdao 266061. china 3. Graduate School, chinese academy of Sciences, Beijing 10003.. china 4. Modern Analysis Center, Nanjing University. Nanjing 210093. china 5. Guangzhou Marine Investigation Bureau, Guangzhou 510760. china 1. institute of oceanology Chinese Academy of Sciences 266071 Qingdao China 2. Key Lab of Marine Sedimentology and Environmental Geology First Institute of Oceanograpgy State Oceanic Administration 266061 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China 4. Modern Analysis Center Nanjing University 210093 Nanjing China 5. Guangzhou Marine Investigation Bureau 510760 Guangzhou China

Fifty-six samples of nannofossil ooze were collected from Core PC5794 in the northern equatorial Pacific at 5 cm intervals. With the methods of mass spectrometer (VG3.4) and ICP, the Nd isotopic compositions (εNd(t)), Mn contents and Mg/Sr ratios of carbonate phase have been analyzed. CaCO3.contents of bulk sediments were obtained by dissolution of 0.5 mol/L HCl. Based on these data, the high-resolution εNd(t) profile of seawater in early Miocene with core depth(or time) have been established. The values of εNd(t) range from -6.2 to -2.97 and 4 fluctuation cycles existed during 24.06-22.02 Ma. 4 low εNd(t) values (about -6.4) correspond to high CaCO3.contents, which implicates that there were 4 cold epochs or 4 times of Antarctic Bottom Water activity. They occurred at the time of 24.06 Ma, 23.85 Ma,22.88 Ma and 22.26 Ma, respectively. High εNd(t) values correspond to the high Mn contents and high values of Mg/Sr ratio, which indicates the existence of 4 intense hydrothermal activity periods during 24.06-22 Ma, the durations of them are 4.05-23.98 Ma, 23.69-23.15 Ma, 22.74-22.3. Ma and 22.06-22.02 Ma, respectively.

关键词：同位素钕示踪原子海水演化中新世太平洋微化石分光计持续期海水样品

Effects of heavy metal ions on larval Penaeus chinensis and comparative study on their elimination methods

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Acta Oceanologica Sinica 1993年第2期12卷 285-293页

作者： Yuan Youxian, Gao Chengnian and Zhang Duxi Yellow Sea Fisheries Research institute, chinese academy of Fishery Sciences,{3., china

In order to establish a new method to eliminate toxicities of heavy metal ions to larval penaeid shrimp, the effects of copper, zinc, lead and cadmium ions on larval metamorphosis of Penaeus chinensis at each stage were determined in detail, and two methods eliminating toxicities were compared. The results indicate that sensitivity of larvae to heavy metal ions decreases in the order of nauplii, protozoea, mysis and postlarvae. The phytoplankton food can reduce, by chetating, the toxicities of heavy metal ions. Both EDTA chelation and PHMA absorption can be used to eliminate the toxicities effectively and there is no significant difference between the two methods. EDTA is harmful to larval P. chinensis at high concentration but affects neither survival nor metamorphosis at below 10 mg/dm3. It is preliminarily observed that copper and zinc ions at low concentration are beneficial to the development of larvae after protozoea stage. It is suggested that it is unnecessary to e-liminate the effects of heavy metal ions in the culture of penaeid shrimp, under normal conditions after protozoea stage.

关键词： Larval Penaeus chinensis copper zinc lead cadmium EDTA polymeric absorbent

Virtualities of quark and gluon in QCD vacuum

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1439-1447页

作者： ZHOU LiJuan1, QIN SongMei2, WU Qing3.& MA WeiXing4 1 Collaboration Group of Hadron Physics and Non-perturbative QCD Study, Guangxi University of Tech- nology, Liuzhou 545006, china 2 Department of Physics, Guangxi University, Nanning 540003. china 3.Department of Physics, qingdao University,{3., china 4 institute of High Energy Physics, chinese academy of Sciences, Beijing 100049, china 1. Collaboration Group of Hadron Physics and Non-perturbative QCD Study Guangxi University of Technology Liuzhou 545006 China 2. Department of Physics Guangxi University Nanning 540003 China 3. Department of Physics Qingdao University Qingdao 266071 China 4. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

The non-local vacuum condensates of quantum chromodynamics (QCD) describe the distributions of quarks and gluons in the non-perturbative QCD vacuum state. Physically, this means that vacuum quarks and gluons have a nonzero mean-squared momentum in the vacuum, called virtuality. The quark virtuality is given by the ratio of the local quark-gluon mixed vacuum condensate to the quark local vacuum condensate. The gluon virtuality is expressed by gluon vacuum condensates and four-quark vacuum condensates. We study the two virtualities by solving Dyson-Schwinger Equations and calculating quark and gluon vacuum condensates. Our theoretical results for quark virtuality are in good agreement with many other theoretical model predictions such as QCD sum rules and lattice QCD calculations. Our calculation on gluon virtuality is initial and the results are quite interesting.

关键词： quark gluon virtuality QCD vacuum condensate non-perturbative QCD