Late Quaternary palaeoenvironmental reconstruction from Lakes Ohrid and Prespa (Macedonia/Albania border) using stable isotopes

Leng, M. J.; Baneschi, I.; Zanchetta, G.; Jex, C. N.; Wagner, B.; Vogel, H. (2010). Late Quaternary palaeoenvironmental reconstruction from Lakes Ohrid and Prespa (Macedonia/Albania border) using stable isotopes. Biogeosciences, 7(10), pp. 3109-3122. Copernicus Publications 10.5194/bg-7-3109-2010

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Abstract. Here we present stable isotope data from three
sediment records from lakes that lie along the Macedonian-
Albanian border (Lake Prespa: 1 core, and Lake Ohrid: 2
cores). The records only overlap for the last 40 kyr, although
the longest record contains the MIS 5/6 transition (Lake
Ohrid). The sedimentary characteristics of both lakes differ
significantly between the glacial and interglacial phases.
At the end of MIS 6 Lake Ohrid’s water level was low (high
�18Ocalcite) and, although productivity was increasing (high
calcite content), the carbon supply was mainly from inorganic
catchment rock sources (high �13Ccarb). During the
last interglacial, calcite and TOC production and preservation
increased, progressively lower �18Ocalcite suggest increase
in humidity and lake levels until around 115 ka. During
ca. 80 ka to 11 ka the lake records suggest cold conditions
as indicated by negligible calcite precipitation and low organic
matter content. In Lake Ohrid, �13Corg are complacent;
in contrast, Lake Prespa shows consistently higher �13Corg
suggesting a low oxidation of 13C-depleted organic matter in
agreement with a general deterioration of climate conditions
during the glacial. From 15 ka to the onset of the Holocene,
calcite and TOC begin to increase, suggesting lake levels
were probably low (high �18Ocalcite). In the Holocene (11 ka
to present) enhanced productivity is manifested by high calcite
and organic matter content. All three cores show an
early Holocene characterised by low �18Ocalcite, apart from
the very early Holocene phase in Prespa where the lowest �18Ocalcite occurs at ca. 7.5 ka, suggesting a phase of higher
lake level only in (the more sensitive) Lake Prespa. From
6 ka, �18Ocalcite suggest progressive aridification, in agreement
with many other records in the Mediterranean, although
the uppermost sediments in one core records low �18Ocalcite
which we interpret as a result of human activity. Overall,
the isotope data present here confirm that these two big lakes
have captured the large scale, low frequency palaeoclimate
variation that is seen in Mediterranean lakes, although in detail
there is much palaeoclimate information that could be
gained, especially small scale, high frequency differences between
this region and the Mediterranean.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Institute of Geological Sciences
08 Faculty of Science > Institute of Geological Sciences > Quaternary Geology

UniBE Contributor:

Vogel, Hendrik

Subjects:

500 Science > 550 Earth sciences & geology

ISSN:

1726-4170

Publisher:

Copernicus Publications

Language:

English

Submitter:

Hendrik Vogel

Date Deposited:

08 Aug 2014 15:40

Last Modified:

13 Dec 2014 08:48

Publisher DOI:

10.5194/bg-7-3109-2010

BORIS DOI:

10.7892/boris.45281

URI:

https://boris.unibe.ch/id/eprint/45281

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