This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ramrath, A. Articles by Negendank, J. F.W. Search for Related Content GeoRef GeoRef Citation Social Bookmarking                   What's this?

Sediments from Lago di Mezzano, central Italy: a record of Lateglacial/Holocene climatic variations and anthropogenic impact

GeoForschungsZentrum Potsdam, Projektbereich 3.3–Sedimente und Beckenbildung, Telegrafenberg, D-14473 Potsdam, Germany; University of Western Australia, Department of Geography, Nedlands WA 6907, Western Australia

Laura Sadori

Università La Sapienza, Dipartimento di Biologia Vegetale, P. le Aldo Moro 5, I-00185 Rome, Italy

Jörg F.W. Negendank

GeoForschungsZentrum Potsdam, Projektbereich 3.3–Sedimente und Beckenbildung, Telegrafenberg, D-14473 Potsdam, Germany

Microscopic, geochemical and pollen analysis of sediment samples of a Lateglacial/Holocene profile from Lago di Mezzano, a maar lake in central Italy, reveals evidence of significant climatic and human-induced environmental changes. Time control is provided by a combination of varve chronology and radiocarbon dating. The well-known Lateglacial climatic variations, a warmer interstadial and the Younger Dryas cold phase are clearly represented in all the parameters. During the interval between 9200 and 5600 cal. BP of the Holocene climatic optimum, annually laminated, organic-rich diatom gyttja was deposited. Two periods of diminished total organic carbon are identified within this interval. The first one (P1) ranges from 8200 to 7800 cal. BP while the second (P2) is centred around 6500 cal. BP. During P1, a predominance of diatoms (Stephanodiscus parvus and S. minutulus) over other algae (represented by the total organic carbon content) is observed. The timing of this period coincides with the early to mid-Holocene climatic transition, reported from ice cores and lake sediments (Stager and Mayewski, 1997). P2 is characterized by a decrease in all biogenic parameters including biogenic opal, organic carbon as well as arboreal pollen. From 5000 cal. BP to date, the sediment pattern changes coincide with the mid-Holocene climatic deterioration. In addition to these natural variations, human impact has been recorded and recognized from sedimentological features such as turbidites and charcoal, as well as from reduced arboreal pollen content. Two Middle Bronze Age (3700 cal. BP and 3300 cal. BP), Etruscan/early Roman (2500 cal. BP), Longobardic (ad 900) and‘modern settlements’ (since ad 1700) have been distinguished on the basis of these data.

Key Words: Laminated sediments • geochemical evidence • pollen analysis • diatoms • climatic change • human impact • Lago di Mezzano • central Italy • Lateglacial • Holocene

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				C. Baroni, G. Zanchetta, A. E. Fallick, and A. Longinelli Mollusca stable isotope record of a core from Lake Frassino, northern Italy: hydrological and climatic changes during the last 14 ka The Holocene, September 1, 2006; 16(6): 827 - 837. [Abstract] [PDF]

				C. Zeilhofer, C. Zielhofer, D. Faust, R. B. Escudero, F. D. del Olmo, A. Kadereit, K.-M. Moldenhauer, and A. Porras Centennial-scale late-Pleistocene to mid-Holocene synthetic profile of the Medjerda Valley, northern Tunisia The Holocene, September 1, 2004; 14(6): 851 - 861. [Abstract] [PDF]