Reducing the Vulnerability of Societies to Water Related Risks at the Basin Scale (Proceedings of the third International Symposium on Integrated Water Resources Management, Bochum, Germany, September 2006). IAHS Publ. 317, 2007, 130–136.

Sediment dynamics from the drainage area into Lake Mladotice (western Czech Republic) in relation to flood events and under the influence of pre- to post-communist landscape changes

ACHIM SCHULTE¹, BOHUMIR JANSKY², GERHARD DAUT³, RALF IRMLER³ & ROBERT VAN GELDERN⁴

1 Institute of Geographical Sciences, Dept of Earth Sciences, Freie Universität Berlin, Malteserstr. 74-100, D-12249 Berlin, Germany

schulte@geog.fu-berlin.de

2 Charles University, Prague, Faculty of Science, Dept of Physical Geography and Geoecology, 128 43 Praha 2, Albertov 6, Czech Republic

3 Department of Geography, University of Jena, Löbdergraben 32, D-07743 Jena, Germany

4 Geochronology and Isotope Hydrology, Leibniz Institute for Applied Geosciences, Stilleweg 2, D-30655 Hannover, Germany

Abstract In May 1872 a landslide occurred in the western Czech Republic, blocking the Mladoticky stream valley and creating Lake Mladotice. The 1952 and 1975 air photos document that collective farming had a great impact when balks and field terraces were removed and fields were made much larger. Because of this change in land use we expected higher soil erosion and a related increase in the sedimentation rate. Our analysis of the sedimentary record aims to identify the factors controlling sediment input, i.e. soil erosion, which is dependent on rainfall–runoff processes and land use in the drainage basin. The sediment stratigraphy, physics, chemistry, micropalaeontology, isotope content and thin sections yield a detailed temporal resolution of the sedimentation chronology. Surprisingly, the sedimentation rates only indicate a small increase from 2.2 cm/year (1954–1963) to 2.7 cm/year (1963–1978) to 2.5 (1978–1986) and 2.4 cm/year (1986–2003).

Key words change in land use; Lake Mladotice; landslide; rainfall–runoff processes; sedimentation rates; soil erosion