Author(s): Adriana Holusova; Lukas Vaverka; Zuzana Polednikova; Tomas Galia

Linked Author(s): Fiona Maager, Zuzana Poledniková

Keywords: River landscape; Morphology; River channel; Meandering

Abstract: The river landscape as a dynamic element is naturally in constant change. This dynamic aspect has often been restricted by human interventions. River regulations such as grade control structures, dams, or channelization affect river flow, morphology, sediment regime and calibre, vegetation cover involvement, or floodplain areas and its connectivity. The Odra River basin is one of the three main river basins in Czechia, where it originates and then flows through Poland and Germany to the Baltic Sea. Like many other large rivers, it has been heavily regulated over the past centuries. Flow regulation effects usually bring a less active river channel and can cause stagnation, aggradation, and more vegetation on river bars, on the one hand, and progressive erosion known as the hungry water effect, usually due to dam construction upstream, on the other. This research aims to analyze how the Odra River and its surrounding landscape have changed in the last few decades on the 50 km reach in the Czech part of the river. It focuses on the morphology of the river, land cover, and land use, within regulated and natural sections, to determine which has been more active during the studied years and what regulations induced these changes. It also aims to evaluate the current condition of the river reach and include it in the overall development of the river landscape. For spatial-temporal analysis, we are using archive and contemporary aerial photographs and orthophoto maps, while the current state is assessing with fieldwork measurements focusing mostly on channel morphology, gravel bars, sediment grain size and lithology, and vegetation cover. At present, preliminary results show an increase in vegetated floodplain areas, including gravel bars, within the last few years, probably due to a lower number or fewer major flood events during this time. We have also observed more active behaviour in the natural meandering section of the river reach, especially from years 2009 to 2012, which included the creation of oxbow lakes and shortening of the river channel.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221132

Year: 2022