RESPONSE OF COCCOLITH RECORDS IN THE SOUTH CHINA SEA TO CARBON ISOTOPE MINIMUM EVENTS
-
摘要: 发生在冰消期时的碳同位素低值事件是晚第四纪以来大洋碳同位素变化的普遍特征。通过对南海北部MD05-2904柱状样(19°27.32'N、116°15.15'E,水深2 066 m,岩心长度4 498 cm)930个沉积物样品中颗石藻属种鉴定,发现颗石藻主要属种Florisphaera profunda,Gephyrocapsa oceanica和Emiliania huxleyi相对百分含量与浮游有孔虫碳同位素变化具有相关性。MIS5期以来δ13C值逐渐变重,颗石藻G.oceanica含量增多,下透光带种F.profunda含量逐渐降低,海水初级生产力升高。对应3次δ13C低值期,颗石藻属种含量都发生明显变化,海水初级生产力出现峰值,说明碳同位素低值事件与浮游植物群落和海洋环境变化有密切关系,颗石藻记录能够为研究大洋碳储库的变化提供依据。Abstract: The occurrence of carbon isotope minimum events at deglaciations is a common feature of marine carbon isotopic records in late Quaternary. Coccolith analysis has been carried out for 930 sediment samples of the core MD05-2904(19°27.32'N, 116°15.15'E,water depth 2 066 m,core length 4 498 cm)from the northern South China Sea. The results revealed that the relative percentage variations of the predominant coccolith taxa (Florisphaera profunda,Gephyrocapsa oceanica and Emiliania huxleyi) were correlated to the carbon isotope record of planktonic foraminifera. While the δ13C became heavier since MIS5, the percentage of G. oceanica increased and lower euphotic species F. profunda decreased, indicating the rise of primary productivity. Corresponding to the three δ13C minimum events, significant changes occurred in the coccolith assemblages and marine primary productivity peaks appeared in deglaciations. It reflects that carbon isotope minimum events may be closely related to the variations of phytoplankton community and paleoenvironmental change. The present results demonstrate that coccolith records can provide evidence for the research of ocean carbon reservoir.
-
Key words:
- coccolith /
- minimum event /
- δ13C /
- primary productivity /
- South China Sea
-
-
[1] Barnola J M, Raynaud D, Korotkevieh Y S, et al. Vostok ice core provides 160000 year record of atmospheric CO2[J]. Nature, 1987, 329:408-414.
[2] 汪品先,田军,成鑫荣,等. 探索大洋碳储库的演变周期[J]. 科学通报,2003,48(21):2216-2227.
[WANG Pinxian, TIAN Jun, CHENG Xinrong, et al. Exploring cyclic changes of the ocean carbon reservoir[J]. Chinese Science Bulletin, 2003, 48(21):2216-2227.]
[3] Wang P, Tian J, Cheng X, et al. Carbon reservoir changes preceded major ice-sheet expansion at the mid-Brunhes event[J]. Geology, 2003, 31(3):239-242.
[4] Wang P, Tian J, Cheng X,et al. Major Pleistocene stages in a carbon perspective:The South China Sea round and its global comparison[J]. Paleoceanography, 2004, 19, doi:10.1029/2003PA000991.
[5] Shackleton N J, Hall M A, Line J, et al. Carbon data in core V19-30 confirm reduced carbon dioxide concentration in the ice age atmosphere[J]. Nature, 1983, 206:319-322.
[6] Oppo D W, Fairbanks R G. Carbon isotope composition of tropical surface water during the past 22000 years[J]. Paleoceanography, 1989, 4:333-351.
[7] Oppo D W, Fairbanks R G, Gordon A L, et al. Late Pleistocene southern ocean δ13C variability[J]. Paleoceanography, 1990, 5:43-54.
[8] Thunell R C, Miao Q, Calvert S E, et al. Glacial-Holocene biogenic sedimentation patterns in the South China Sea:productivity variations and surface water CO2[J]. Paleoceanography, 1992, 7:143-162.
[9] Linsley B K, Dunbar R B. The late Pleistocene history of surface water in the Sulu Sea:Possible relationship to Pacific deep water δ13C changes[J]. Paleoceanography, 1994, 9:317-340.
[10] Spero H J, Lea D W. The cause of carbon isotope minimum events on glacial terminations[J]. Science, 2002, 296:522-525.
[11] 李铁刚,刘振夏,Hall M A, et al. 冲绳海槽末次冰消期浮游有孔虫δ13C的宽幅低值事件[J]. 科学通报,2002, 47(4):298-301.
[LI Tiegang, LIU Zhenxia, Hall M A, et al. A broad deglacial δ13C minimum event in planktonic foraminiferal records in the Okinawa Trough[J]. Chinese Science Bulletin, 2002, 47(4):298-301.]
[12] 李铁刚,赵京涛,孙荣涛,等. 250 kaBP以来西太平洋暖池中心区——Ontong Java海台古生产力演化[J]. 第四纪研究, 2008, 28(3):447-457.
[LI Tiegang, ZHAO Jingtao, SUN Rongtao, et al. Paleoproductivity evolution in the Ontong Java plateau-center of the Western Pacific Warm Pool during the last 250 ka[J]. Quaternary Sciences, 2008, 28(3):447-457.]
[13] 刘传联,成鑫荣. 从钙质超微化石看南沙海区近2 Ma海水上层结构的变化[J]. 中国科学D辑,2001,31(10):834-839.
[LIU Chuanlian, CHENG Xinrong. Exploring variations in upper ocean structure for the last 2 Ma of the Nansha area by means of calcareous nannofossils[J]. Science in China (Series D), 2001, 31(10):834-839.]
[14] Bollmann J, Baumann K H, Thierstein H R. Global dominance of Gephyrocapsa coccolith in late Pleistocene:selective dissolution, evolution or global environmental change?[J]. Paleoceanography, 1998, 13:517-529.
[15] Liu C, Wang P, Tian J, et al. Coccolith evidence for Quaternary nutricline variations in the southern South China Sea[J]. Marine Micropaleontology, 2008, 69:42-51.
[16] Laj C, Wang P, Balut Y, et al. MD147-Marco Polo IMAGES Ⅻ Cruise Report[R]. France:Institute Paul-Emile Victor (IPEV), 2005.
[17] Dollfus D, Beaufort L. Fat neural network for recognition of position-normalised objects[J]. Neural Networks, 1999, 12:553-560.
[18] Beaufort L, Dollfus D. Automatic recognition of coccoliths by dynamical neural networks[J]. Marine Micropaleontology, 2004, 51:57-73.
[19] 苏翔,刘传联. 颗石藻自动鉴定系统及其古海洋学应用——以南海MD05-2901柱状样研究为例[J]. 微体古生物学报,2008,25(4):385-392.
[SU Xiang, LIU Chuanlian. Application of automatic recognition system for coccoliths in paleoceanography:a case study at site MD05-2901, South China Sea[J]. Acta Micropalaeontologica Sinica, 2008, 25(4):385-392.]
[20] 葛黄敏,李前裕,成鑫荣,等. 南海北部晚第四纪高分辨率浮游氧同位素地层学及其古气候信息[J]. 地球科学——中国地质大学学报,2010,35(4):515-525.
[GE Huangmin, LI Qianyu, CHENG Xinrong, et al. Late Quaternary high resolution monsoon records in planktonic stable isotopes from northern South China Sea[J]. Earth Science-Journal of China University of Geosciences, 2010, 35(4):515-525.]
[21] Okada H, Honjo S. The distribution of oceanic coccolithophorids in the Pacific[J]. Deep Sea Research, 1973, 20:355-364.
[22] Beaufort L, Lancelot Y, Camberlin P, et al. Insolation cycles as a major control of equatorial Indian Ocean primary production[J]. Science, 1997, 278:1451-1454.
[23] De Garidel-Thoron T, Beaufort L, Linsley B K, et al. Millennial-scale dynamics of the East Asian winter monsoon during the last 200000 years[J]. Paleoceanogaphy, 2001, 16:1-12.
[24] 李建如,汪品先. 南海20万年来的碳同位素记录[J]. 科学通报,2006,51(12):1482-1486.
[LI Jianru, WANG Pinxian. A 200-ka carbon isotope record from the South China Sea[J]. Chinese Science Bulletin, 2006,51(12):1482-1486.]
[25] Okazaki Y, Timmermann A, Menviel L, et al. Deepwater Formation in the North Pacific During the Last Glacial Termination[J]. Science, 2010, 329, doi:10.1126/science. 1190612.
[26] Waelbroeck C, Labeyrie L, Michel E, et al. Sea-level and deep water temperature changes derived from benthic foraminifera isotopic records[J]. Quaternary Science Reviews, 2002(21):295-305.
[27] Petit J R, Jouzel J, Raynaud D, et al. Climate and atmospheric history of the past 420000 years from the Vostok ice core, Antarctica[J]. Nature, 1999, 399:429-436.
[28] 贺娟,赵美训,李丽,等. 南海北部MD05-2904沉积柱状样26万年以来表层海水温度及陆源生物标记物记录[J]. 科学通报,2008, 53(11):1324-1331.
[HE Juan, ZHAO Meixun, LI Li, et al. Sea surface temperature and terrestrial biomarker records of the last 260 ka of core MD05-2904 form the northern South China Sea[J]. Chinese Science Bulletin, 2008, 53(11):1324-1331.]
[29] Lourantou A, Chappellaz J, Barnola J-M, et al. Changes in atmospheric CO2 and its carbon isotopic ratio during the penultimate deglaciation[J]. Quaternary Science Reviews, 2010, 29:1983-1992.
-
计量
- 文章访问数: 1049
- PDF下载数: 1
- 施引文献: 0
下载: