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DOI	10.1016/j.quascirev.2019.02.011
	Dinocyst records from deep cores reveal a reversed salinity gradient in the Caspian Sea at 8.5–4.0 cal ka BP
	Leroy S.A.G.; López-Merino L.; Kozina N.
发表日期	2019
ISSN	0277-3791
起始页码	1
结束页码	12
卷号	209
英文摘要	Understanding the long-term environmental forcings driving Caspian Sea (CS) water levels is of utmost importance, not only owing to its large size, or to the surrounding developing economies but also to improve global climate models and forecasts. However, Late Quaternary CS level changes and their amplitude are mostly documented from incomplete coastal sediment records. Because of the CS idiosyncrasies, that behaves neither as a sea nor as a lake, the methods used to reconstruct water levels in the global ocean or in freshwater lakes do not always apply. Here, we propose a first step toward the use of dinoflagellate cysts records to reconstruct qualitative changes in water mass, focusing on new and published deep-water sedimentary sequences from the south and middle CS basins. Trends in water level changes are reconstructed on the relative proportions of dinocyst assemblages with different levels of brackishness. A higher highstand than previously seen is reconstructed post-Mangyshlak lowstand. A reverse water flow gradient from S to N, not previously detected, is identified at 8.5–8 to 4 cal ka BP. A major turnover in dinocyst assemblage is found at 4 cal ka BP. While the Volga River is the main source of water nowadays, we propose that the source of water to maintain the 8.5–8 to 4 cal ka BP highstand is the now-disconnected drainage basin of the Amu-Darya. The CS was at that time most likely strongly influenced by low latitude climates, with more precipitation over the Karakum and, perhaps, even indirect monsoonal influence. © 2019
英文关键词	Amu-Darya; Micropalaeontology dinocyst; Palaeolimnology; Pontocaspian; Quaternary; Southwestern Asia; Water flow direction
语种	英语
scopus关键词	Catchments; Flow of water; Hydraulics; Lakes; Water levels; Amu-Darya; Micropalaeontology dinocyst; Palaeolimnology; Ponto-caspian; Quaternary; Southwestern Asia; Water flow direction; Climate models; climate modeling; coastal sediment; dinoflagellate cyst; drainage basin; freshwater environment; global climate; global ocean; paleolimnology; Quaternary; salinity; water flow; water level; Amu Darya Basin; Caspian Sea; Karakum; Russian Federation; Turkmenistan; Volga River; Dinophyceae
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151996
作者单位	Aix Marseille Univ, CNRS, Minist Culture, LAMPEA, UMR 7269, 5 rue du Château de l'Horloge, Aix-en-Provence, 13094, France; Department of Geography, Geology and the Environment, Kingston University, Penrhyn Road, Kingston upon Thames, Surrey, KT1 2EE, United Kingdom; Shirshov Institute of Oceanology, Russian Academy of Science, Russian Federation
推荐引用方式 GB/T 7714	Leroy S.A.G.,López-Merino L.,Kozina N.. Dinocyst records from deep cores reveal a reversed salinity gradient in the Caspian Sea at 8.5–4.0 cal ka BP[J],2019,209.
APA	Leroy S.A.G.,López-Merino L.,&Kozina N..(2019).Dinocyst records from deep cores reveal a reversed salinity gradient in the Caspian Sea at 8.5–4.0 cal ka BP.Quaternary Science Reviews,209.
MLA	Leroy S.A.G.,et al."Dinocyst records from deep cores reveal a reversed salinity gradient in the Caspian Sea at 8.5–4.0 cal ka BP".Quaternary Science Reviews 209(2019).