Lipid Biomarkers in Lacustrine Sedimentary Archives – An Inventory and Evaluation as Proxies for Environmental and Climatic Change

With the growing understanding of human influence on the Earth system, an increasing number of scientific investigations focuses on vegetation responses to changing environmental and/ or climatic conditions. A detailed prediction, how e.g. increasing atmospheric temperatures affect the composition of terrestrial and aquatic vegetation composition, however, remains difficult without a detailed knowledge of comparable changes during the past. A number of archives recording changes in environmental and/ or climatic conditions under varying temporal integration and resolution have been evaluated up to now. Changing conditions are, however, not recorded directly. Measured proxyparameters need to be interpreted and correlated to environmental and climatic parameters. Lacustrine sedimentary archives are generally regarded as excellent archives in terms of paleolimnology. Sediments of two maar lakes, a special form of crater lakes, have been selected as sedimentary records for the study presented here. The lipid composition of Lake Holzmaar and Lake Meerfelder Maar sediments has been evaluated with respect to varying proportions of autochthonous and allochthonous organic matter contribution. In a second step, detected changes in organic matter contributing sources were correlated to environmental and climatic changes. In order to overcome the reginal scale of this investigation, sediments from Lake Großer Treppelsee, eastern Brandenburg, were added to this study and investigated under the same programme. A selected section of Lake Meerfelder Maar sedimentary profile including the Younger Dryas cold period and the transition to the early Ho-