Resumen de Late-Glacial and Holocene Environmental History of an Oxbow Wetland in the Polabí Lowland (River Elbe, Czech Republic); a Context-Dependent Interpretation of a Multi-Proxy Analysis
Libor Petr,, Jiri Sadlo,, Pavla Zacková,, Lenka Lisá,, Jan Novák,
This study presents a palaeoenvironmental reconstruction of an oxbow wetland covering the past 11,500 years. The origin of the oxbow lake and development of the floodplain wetland and changes of the surrounding vegetation are reconstructed using palaeobotanical analyses, radiocarbon dating, detailed sediment stratigraphy and micromorphology of samples taken from a former palaeomeander of the river Elbe in the Czech Republic. The sedimentary record of the section Chrast was chosen due to its exceptional position within the area of former oxbow lakes. Using a multi-proxy approach, we investigated how this environment reflected climatic changes during the Holocene. Our results show that the Chrast section covers the Late-Glacial to the Middle Holocene period, which is climatically very unstable and characterized by extensive vegetation and sedimentological changes. The macrofossil record provides detailed evidence of Allerød vegetation. The sedimentological record reflects changes in fluvial activity (meandering-braided transition in the channel pattern) during Late-Glacial/Holocene and postsedimentological changes (occurrence of a doplerite layer) in the middle Holocene. We follow three independent lines of interpretation: (a) a local autogenic environmental-succession process, (b) a regional process driven by climate change, and (c) the role of stochastic and indeterministic processes.
