DOI: 10.1016/j.quascirev.2013.07.032
Scopus记录号: 2-s2.0-84883307078
论文题名: From the Allerød to the mid-Holocene: Palynological evidence from the south basin of the Caspian Sea
作者: Leroy S.A.G. ; Tudryn A. ; Chalié F. ; López-Merino L. ; Gasse F.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 78 起始页码: 77
结束页码: 97
语种: 英语
英文关键词: Caspian Sea
; Dinocysts
; Holocene
; Palaeohydrography
; Pollen
; Sea level fluctuations
; Vegetation
; Younger Dryas
Scopus关键词: Caspian sea
; Dinocysts
; Holocenes
; Palaeohydrography
; Pollen
; Sea-level fluctuations
; Younger Dryas
; Arid regions
; Climate change
; Lithology
; Sea level
; Silt
; Vegetation
; Glacial geology
; Allerod
; arid environment
; carbonate
; climate change
; cyst
; Holocene
; lithology
; meltwater
; palynology
; radiocarbon dating
; salinity
; silt
; steppe
; water flow
; California
; Caspian Sea
; San Francisco Bay
; South Basin
; United States
英文摘要: Pollen and dinoflagellate cysts have been analysed in a core from the south basin of the Caspian Sea, providing a picture of respectively past vegetation and water salinity for the Late Pleistocene to middle Holocene. A relatively sharp lithological change at 0.86m depth reflects a shift from detrital silts to carbonates-rich fine silts. From this depth upwards, a Holocene chronology is built based on ten radiocarbon dates on ostracod shells and bulk carbonates.From the vegetation point of view, the Late Pleistocene deserts and steppes were partially replaced in the most sheltered areas by an open woodland with Pinus, Juniperus-Hippophae-Elaeagnus and even Alnus-Quercus-Pterocarya and Fraxinus, related to the Allerød palynozone. This was interrupted by the Younger Dryas palynozone when Artemisia reaches a maximum in a first instance followed by a very dry phase with only a slight return of Pinus and Quercus and the rare presence of Ulmus-Zelkova. From 11.5 to 8.4cal.kaBP, an open landscape dominated by shrubs such as Ephedra and progressively increasing Quercus appeared. The final spread of diverse evergreen and deciduous trees is delayed and occurs after 8.4cal.kaBP. It is suggested that this delay is caused by an arid climate in the Early Holocene linked to high insolation and perhaps to a lake effect.The dinocyst assemblages fluctuate between slightly brackish (Pyxidinopsis psilata and Spiniferites cruciformis, 7psu and lower) and more brackish (Impagidinium caspienense, ~13psu). In the Lateglacial (Khvalynian highstand), the assemblages remained dominated by relative low salinity taxa. A late and brief increase of salinity occurred prior to 11.2cal.kaBP associated with the Mangyshlak lowstand. It is suggested that it was caused by a brief drop in meltwater flow from both the north and the southeast (Uzboy) and a likely evaporation increase. This lowstand occurs quasi at the same time as the end of a longer lowstand in the Black Sea. The freshest waters are then inferred as having occurred between 8.4 and ≤4.4cal.kaBP, linked to a connection with the Amu Darya and the melting glaciers on the Pamir Mountains.The Caspian Sea is a sensitive environment, easily perturbed by global climatic changes, such as the Allerød and Holocene warming, and the Lateglacial and Younger Dryas cooling, as well as by regional changes in its hydrography, such as shifts in the Eurasian meltwater and the Volga and Amu Darya inflows. © 2013 The Authors. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60492
Appears in Collections: 过去全球变化的重建
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作者单位: Institute for the Environment, Brunel University, Uxbridge, UB8 3PH London, United Kingdom; Univ Paris-Sud, Laboratoire IDES, UMR8148, Orsay F-91405, France; CNRS, Orsay F-91405, France; CEREGE, UM 34 Aix-Marseille Université-CNRS UMR 7330- IRD UMR 161, EuropÔle Méditerranéen de l'Arbois, BP80, F-13545, Aix-en-Provence Cedex 04, France
Recommended Citation:
Leroy S.A.G.,Tudryn A.,Chalié F.,et al. From the Allerød to the mid-Holocene: Palynological evidence from the south basin of the Caspian Sea[J]. Quaternary Science Reviews,2013-01-01,78