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Lücke, A.,Zolitschka, B. 2003 A Lateglacial and Holocene organic carbon isotope record of lacustrine palaeoproductivity and
climate change derived from varved lake sediments of Lake Holzmaar, Germany. Quaternary Science Reviews Vol.22, Issues 5-7,
pp. 569-580, March 2003.
| Data Coverage |
North: 50.1166 * South: 50.1166 |
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West: 6.8833 * East: 6.8833 |
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Altitude: 425 m |
Start Year: 11492 cal yr BP * End Year: 419 cal yr BP
Data: Please Cite Data Contributors!
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Summary: A composite varve-dated 11.4 m long sediment sequence from Lake Holzmaar,
situated in the Eifel region of western Germany, was investigated for
total organic matter content, total nitrogen content and stable organic
carbon isotopes. Mean time resolution is 75 years for TN and 14 years
for d13Corg. On millennial time scales primary production of lacustrine
algae strongly depends on the delivery of nutrients from the catchment.
The respective carbon isotope record is characterized by marked variations
of d13Corg ranging from -36.0 per mil to -27.0 per mil and includes
a number of pronounced shifts. Reactions of the lacustrine system
and the catchment to changes of environmental parameters, e.g. runoff,
solar radiation and temperature, induce changes of algal associations
and of lacustrine primary production which are reflected in the sediments
as carbon isotope variations. Clear evidence of ecosystem reorganizations
is detected by the carbon isotope record around 14,200, 10,400, 9600, 5500,
2700, 1700 and 900 varve years BP. In particular, the Holocene events
of 9600, around 5500 and 2700 are interpreted as the expression of massive
changes of the climate system. The steady rise of d13Corg values during
the mid-Holocene is interpreted as a continuous climatic amelioration
reaching an optimum around 6500 varve years BP. Rapid and large changes
of d13Corg values from 2700 varve years BP to the present indicate major
disturbances in the catchment area. These are most probably related to
deforestation or reforestation and runoff changes, presumably
in conjunction with human impact. Carbon isotopes, thus, characterize
the Holzmaar ecosystem in time revealing lacustrine palaeoproductivity
as well as providing palaeoenvironmental and palaeoclimatic information.
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