CHILL-10, 000 @ Lochnagar, Cairngorm Mountains
by
Catherine P. Dalton
Department of Geography,Mary Immaculate College, UNIVERSITY OF LIMERICK, Ireland
Coauthors: Battarbee, R.W., Birks, H.J.B., Brooks, S.J., Cameron, N.G., Derrick, S., Evershed, R. P., Peglar, S.M., Scott, J.A., Thompson, R.

The CHILL 10, 000 project was funded under the EU Framework V, Environment and Climate Programme. The aim of CHILL-10, 000 was to quantitatively investigate past climate changes as recorded in lake deposits in ecologically sensitive situations. Lochnagar in the Scottish Caringorms was selected, along with seven other high altitude lakes, for high resolution examination of their Holocene sedimentological and biological sequences. Lochnagar is a corrie loch and is ideally suited as it is situated in the only natural alpine environment in the UK, has high quality monitoring data available.

Lake sediment cores were retrieved representing a c. 9, 000 Cal yrs BP. High resolution microfossil (pollen, diatoms and chironomids) and sedimentological proxies (organic matter, minerogenic matter, biomarkers, lipid analyses, mineral magnetism and particle size) were examined to reconstruct past climate conditions.

The major pattern of long-term change in the fossil pollen data is a progressive loss of woodland cover and soil deterioration from brown-earths to podsols and shallow peat. Highly distinctive cycles in LOI during the last 6000 years were reflected in bulk and lipid geochemical analysis. Biomarker studies have succeeded in quantifying the relative proportions of autochthonous and allochthonous organic matter in the Lochnagar sediments and are expected to provide a more direct link with palaeoclimate. Diatom analyses show a general decline in pH and this was supported by the results of chironomdae analysis while inferred temperatures fluctuate throughout the Holocene period. The potential of these high altitude lake sites as high-resolution sensors of environmental change has been realised in some proxies but not in others. The highly characteristic results from Lochnagar remain an interesting phenomenon.

Date received: July 3, 2001

Copyright © 2001 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # cahr-45.