DOI: 10.1016/j.quascirev.2015.10.044
Scopus记录号: 2-s2.0-84946600106
论文题名: Centennial to millennial-scale changes in oxygenation and productivity in the Eastern Tropical South Pacific during the last 25,000 years
作者: Salvatteci R. ; Gutierrez D. ; Sifeddine A. ; Ortlieb L. ; Druffel E. ; Boussafir M. ; Schneider R.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 131 起始页码: 102
结束页码: 117
语种: 英语
英文关键词: Denitrification
; Oxygen minimum zone
; Paleoceanography
; Peruvian upwelling ecosystem
; Redox sensitive metals
Scopus关键词: Biochemical oxygen demand
; Carbon
; Climate change
; Denitrification
; Flow of water
; Glacial geology
; Oceanography
; Organic carbon
; Oxygen
; Oxygenation
; Productivity
; Sediments
; Tropics
; Antarctic cold reversals
; Antarctic intermediate waters
; Equatorial undercurrents
; Marine biogeochemistries
; Medieval climate anomalies
; Oxygen minimum zone
; Paleoceanography
; Redox-sensitive metals
; Dissolved oxygen
; Antarctic Intermediate Water
; biogeochemistry
; climate variation
; denitrification
; Last Glacial Maximum
; Little Ice Age
; Medieval
; oceanic circulation
; oxygenation
; paleoceanography
; reconstruction
; redox conditions
; timescale
; Pacific Ocean
; Pacific Ocean (South)
; Pacific Ocean (Tropical)
英文摘要: Oxygen minimum zones (OMZ) have expanded in all tropical oceans during the last 50 years resulting in habitat contraction and considerable changes in marine biogeochemistry. However, for a better understanding of the OMZ dynamics under the current climate change, two questions are relevant: 1) how do the magnitude and temporal changes in oceanic dissolved oxygen of the last few decades compare to the natural variability on longer timescales, and 2) what were the local and remote factors driving OMZ changes in the past. In the present study we use a stacked record covering the last 25 kyr from the Eastern Tropical South Pacific (ETSP) OMZ to reconstruct changes in oxygenation and productivity. We use a suite of proxies including the presence of laminations, redox sensitive metals (U, Mo, Re, Ni and Cu), total organic carbon and δ15N measurements. Water column denitrification and sediment redox conditions show pronounced centennial to millennial-scale variability during the last 25 kyr, with oxygenation levels as low as at present. Global cold periods at different timescales such as the Last Glacial Maximum (23-19 kyr BP) and the Little Ice Age (1500-1850 AD) were associated with a weak OMZ and low export production, while warm intervals such as the deglaciation, part of the Medieval Climate Anomaly and the last 100 years are associated with a stronger OMZ and high export production. Water column denitrification and sediment redox conditions were strongly coupled during the last 25 kyr BP apart from one remarkable exception: during the Antarctic Cold Reversal, sediments were less reducing but the water column denitrification was high resulting in a strong but shallow OMZ. This may have been produced by an enhanced Antarctic Intermediate Water flow. Contrary to our expectations and modeling predictions for the next few decades, we observe a weak ETSP-OMZ during the warm mid-Holocene, which may have been the result of a stronger Walker Circulation that brought oxygen-rich waters to intermediate depths off Peru via Equatorial undercurrents. In combination with other paleoceanographic reconstructions, our results show that oxygenation variability in the ETSP-OMZ was influenced by ocean circulation changes in the Tropical Pacific, high latitude oceanographic and climatic changes, and local productivity. © 2015 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59737
Appears in Collections: 过去全球变化的重建
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作者单位: IRD-Sorbonne Universités (UPMC, Univ. Paris 06)-CNRS-MNHN, LOCEAN Laboratory, Center IRD France-Nord, 32, Avenue Henri Varagnat, Bondy, France; Institute of Geosciences, Kiel University, Ludewig-Meyn-Str. 10, Kiel, Germany; Instituto Del Mar Del Perú, Esquina Gamarra y General Valle s/n, Callao, Peru; Programa Maestría en Ciencias Del Mar, Universidad Peruana Cayetano Heredia, Lima, Peru; Departamento de Geoquimica, Universidade Federal Fluminense, Niteroi, Brazil; Department of Earth System Science, University of California, Irvine, CA, United States; Institut des Sciences de la Terre d'Orléans, UMR7327 - INSU/CNRS/BRGM/Université d'Orléans, 1A Rue de la Férollerie, Orléans CEDEX-2, France
Recommended Citation:
Salvatteci R.,Gutierrez D.,Sifeddine A.,et al. Centennial to millennial-scale changes in oxygenation and productivity in the Eastern Tropical South Pacific during the last 25,000 years[J]. Quaternary Science Reviews,2016-01-01,131