Benthic foraminiferal paleoceanography of the South China Sea over the last 40,000 years

Benthic foraminifera in gravity and piston cores from two sites of the northern and southern slopes of the South China Sea (SCS) were analyzed to evaluate changes in surface productivity and deep-water mass characteristics over the last 40,000 years. Our observations suggest that changes in organic carbon flux, that is food supply, and chemical and=or physical properties of the ambient water mass may be the two primary and intercorrelated factors controlling the distribution patterns of benthic foraminifera. When organic carbon flux increased above 3.5 g C m 2 yr 1 in the southern SCS during the last glacial maximum and in the northern SCS during the first part of the Holocene around 10 ka B.P., a group of detritus feeders including Bulimina aculeata and Uvigerina peregrina dominated the benthic foraminiferal assemblage as shown by relative abundance (%) and accumulation rates. This may reflect episodes of increased surface productivity, possibly induced by increased input of nutrients from nearby river runoff. Suspension feeders such as Cibicidoides wuellerstorfiand a group of ‘opportunistic’ species including Oridorsalis umbonatus, Melonis barleeanum and Chilostomella ovoidea gradually became more abundant than detritus feeders as soon as the organic carbon flux decreased to 2.5‐3.5 g C m 2 yr 1 . Similar glacial to interglacial changes in relative abundance and accumulation rates were observed in both cores for a number of species, including Eggerella bradyi, Globocassidulina subglobosa , Astrononion novozealandicum , Sphaeroidina bulloidesand Cibicidoides robertsonianus. These changes were not correlated to the distribution patterns of organic carbon in both cores and may have been related to yet unspecified changes in chemical and=or physical properties of the ambient water mass, independent of changes in organic carbon flux. © 1999 Elsevier Science B.V. All rights reserved.

[1]  P. Loubere,et al.  Taphonomic Process and Species Microhabitats in the Living to Fossil Assemblage Transition of Deeper Water Benthic Foraminifera , 1990 .

[2]  Michael Sarnthein,et al.  Atmospheric summer circulation and coastal upwelling in the Arabian Sea during the Holocene and the last glaciation , 1991, Quaternary Research.

[3]  M. Maslin,et al.  Northeastern Atlantic benthic foraminifera during the last 45,000 years: Changes in productivity seen from the bottom up , 1995 .

[4]  C. Summerhayes,et al.  Upwelling systems : evolution since the Early Miocene , 1992 .

[5]  E. Jansen,et al.  Evidence for a bathyal front at 2000‐M depth in the glacial Pacific, based on a depth transect on Ontong Java Plateau , 1992 .

[6]  Z. Jian,et al.  Late quaternary benthic foraminifera and deep-water paleoceanography in the South China Sea , 1997 .

[7]  M. Sarnthein,et al.  Transfer functions to reconstruct ocean palaeoproductivity: a comparison , 1992, Geological Society, London, Special Publications.

[8]  R. Thunell,et al.  Recent deep-sea benthic foraminiferal distributions in the South China and Sulu Seas , 1993 .

[9]  W. Broecker,et al.  New evidence from the South China Sea for an abrupt termination of the last glacial period , 1988, Nature.

[10]  M. Machain-Castillo,et al.  Benthic foraminifera in oxygen-poor habitats , 1993 .

[11]  L. Collins.  Relationship of environmental gradients to morphologic variation within Bulimina aculeata and Bulimina marginata, Gulf of Maine area , 1989 .

[12]  J. Duplessy.  Glacial to interglacial contrasts in the northern Indian Ocean , 1982, Nature.

[13]  H. B. Brady,et al.  Taxonomic notes on the species figured by H. B. Brady in his report on the foraminifera dredged by H. M. S. Challenger during the years 1873-1876, accompanied by a reproduction of Brady's plates , 1960 .

[14]  M. G. Wiesner,et al.  Fluxes of particulate matter in the South China Sea , 1996 .

[15]  M. Stuiver,et al.  Modeling Atmospheric 14C Influences and 14C Ages of Marine Samples to 10,000 BC , 1993, Radiocarbon: An International Journal of Cosmogenic Isotope Research.

[16]  S. Streeter.  Bottom Water and Benthonic Foraminifera in the North Atlantic—Glacial-Interglacial Contrasts , 1973, Quaternary Research.

[17]  R. Barker.  Taxonomic notes on the species , 1960 .

[18]  Pinxian Wang,et al.  Late Quaternary paleoceanography of the South China Sea: surface circulation and carbonate cycles , 1995 .

[19]  G. P. Lohmann,et al.  Environmental distribution of Recent benthic foraminifera on the northeast United States continental slope , 1982 .

[20]  W. Kuhnt,et al.  Seasonality in microhabitats of rose bengal stained deep-sea benthic foraminifera from the New Jersey continental margin , 1997 .

[21]  M. Stuiver,et al.  High-Precision Decadal Calibration of the Radiocarbon Time Scale, AD 1950–6000 BC , 1993, Radiocarbon.

[22]  Laurent Labeyrie,et al.  Deepwater source variations during the last climatic cycle and their impact on the global deepwater circulation , 1988 .

[23]  R. Thunell,et al.  Late Pleistocene-Holocene distribution of deep-sea benthic foraminifera in the South China Sea and Sulu Sea; paleoceanographic implications , 1996 .

[24]  A. Rathburn,et al.  The ecology of living (stained) deep‐sea benthic foraminifera from the Sulu Sea , 1994 .

[25]  M. Sarnthein,et al.  Late Quaternary changes in surface water and deep water masses of the Nordic Seas and north-eastern North Atlantic: a review , 1995 .

[26]  J. Kennett,et al.  Late Quaternary paleoceanography as recorded by benthonic foraminifera in Strait of Sicily sediment sequences , 1984 .

[27]  K. Winn.  Oxygen/carbon isotopes and paleoproductivity in the South China Sea during the past 110 000 years , 1990 .

[28]  W. Kuhnt,et al.  Quantitative composition of benthic foraminiferal assemblages as a proxy indicator for organic carbon flux rates in the South China Sea , 1999 .

[29]  G. P. Lohmann.  Abyssal benthonic foraminifera as hydrographic indicators in the western South Atlantic Ocean , 1978 .

[30]  R. Thunell.  Optimum indices of calcium carbonate dissolution, in deep-sea sediments , 1976 .

[31]  J. Kutzbach,et al.  Monsoon Climate of the Early Holocene: Climate Experiment with the Earth's Orbital Parameters for 9000 Years Ago , 1981, Science.

[32]  A. Altenbach.  Short term processes and patterns in the foraminiferal response to organic flux rates , 1992 .

[33]  N. Shackleton,et al.  Paleocirculation of the Deep North Atlantic: 150,000-Year Record of Benthic Foraminifera and Oxygen-18 , 1979, Science.

[34]  D. Anderson,et al.  Glacial‐Holocene carbonate dissolution and sea surface temperatures in the south China and Sulu seas , 1994 .

[35]  R. Thunell,et al.  Oxygen minimum expansion in the Sulu Sea, western equatorial Pacific, during the last glacial low stand of sea level , 1985 .

[36]  J. Herguera.  Deep-sea benthic foraminifera and biogenic opal: Glacial to postglacial productivity changes in the western equatorial Pacific , 1992 .

[37]  Joan O. Grimalt,et al.  East Asian monsoon climate during the Late Pleistocene: high-resolution sediment records from the south China Sea , 1999 .

[38]  H. Mao,et al.  In reply: evidence for band overlap metallization of hydrogen. , 1990, Science.

[39]  W. Berger,et al.  Benthic foraminifera in box core ERDC 112, Ontong Java Plateau , 1993 .

[40]  G. Pearson,et al.  High-precison (super 14) C measurement of German and Irish oaks to show the natural (super 14) C variations from 7890 to 5000 BC. , 1993 .

[41]  G. Keller,et al.  Benthic Foraminiferal Biofacies, Sediments and Water Masses of the Southern Peru-Chile Trench Area, Southeastern Pacific Ocean , 1980 .

[42]  N. Shackleton,et al.  Carbonate Dissolution Fluctuations in the Western Equatorial Pacific During the Late Quaternary , 1992 .

[43]  J. Duplessy,et al.  Changes in the distribution of δ13C of deep water ΣCO2 between the Last Glaciation and the Holocene , 1988 .

[44]  G. Shimmield,et al.  Impact of productivity events on the benthic foraminiferal fauna in the Arabian Sea over the last 150,000 years , 1995 .

[45]  Hemipelagic Sediment Accumulation Rates in the South China Sea Related to Late Quaternary Sea-Level Changes , 1993 .

[46]  W. Berger.  Ocean ventilation during the last 12,000 years: Hypothesis of counterpoint deep water production , 1987 .

[47]  J. Duplessy,et al.  Century-scale events in monsoonal climate over the past 24,000 years , 1993, Nature.

[48]  Xiangjun Sun,et al.  A pollen record of the last 37 ka in deep sea core 17940 from the northern slope of the South China Sea , 1999 .

[49]  M. Sarnthein,et al.  Transfer functions to reconstruct ocean paleoproductivity, a comparison. In: Summerhayes et al. (eds), Evolution of Upwelling Systems since the Early Miocene , 1992 .

[50]  B. Corliss,et al.  Morphotype patterns of Norwegian Sea deep-sea benthic foraminifera and ecological implications , 1988 .

[51]  E. Bard,et al.  Calibration of the 14C timescale over the past 30,000 years using mass spectrometric U–Th ages from Barbados corals , 1990, Nature.

[52]  E. Duursma.  Productivity of the ocean: Present and past: Edited by W.H. Berger, V.S. Smetacek and G. Wefer. John Wiley & Sons, Chichester, UK 1989. A Dahlem Workshop Report, Life Sciences Research Rep. 44. xiii + 471 pp. ISBN 0-471-92246-3 , 1992 .

[53]  Pinxian Wang,et al.  Late Quaternary paleoceanography of the South China Sea: Glacial‐interglacial contrasts in an enclosed basin , 1990 .

[54]  Ping-Tung Shaw,et al.  Deep water ventilation in the South China Sea , 1996 .

[55]  R. Thunell,et al.  Glacial‐Holocene Biogenic Sedimentation Patterns in the South China Sea: Productivity Variations and Surface Water pCO2 , 1992 .

[56]  J. E. Klovan,et al.  An algorithm andFortran-iv program for large-scaleQ-mode factor analysis and calculation of factor scores , 1971 .

[57]  D. Martinson,et al.  Late Quaternary deep-ocean circulation , 1986 .

[58]  G. Shimmield,et al.  The importance of the oxygen minimum zone and sediment geochemistry in the distribution of Recent benthic foraminifera in the northwest Indian Ocean , 1990 .

[59]  H. Ujiié.  Bathyal Benthic Foraminifera in a Piston Core from East off the Miyako Islands,Ryukyu Island Arc , 1990 .

[60]  E. Boyle.  Quaternary Deepwater Paleoceanography , 1990, Science.

[61]  J. Duplessy,et al.  Radiocarbon age of last glacial Pacific deep water , 1988, Nature.

[62]  S. Clemens,et al.  Forcing mechanisms of the Indian Ocean monsoon , 1991, Nature.

[63]  B. Corliss.  Microhabitats of benthic foraminifera within deep-sea sediments , 1985, Nature.

[64]  W. T. Coulbourn,et al.  Recent benthic foraminifera from the continental margin of northwest Africa: Community structure and distribution , 1984 .

[65]  M. Stuiver,et al.  High-Precision Bidecadal Calibration of the Radiocarbon Time Scale, AD 1950–500 BC and 2500–6000 BC , 1993, Radiocarbon.

[66]  V. Ittekkot.  Particle flux in the ocean , 1996 .