The contribution of geomorphological processes to urban landscape modification, Poznan, Poland

Abstract

<p>The poster will present the role of contemporary morphogenetic processes in shaping the morphological landscape of the city of Poznań (530 464 inhabitants). The study is based on geocomputation performed on a digital elevation model, analysis of geomorphological evolution of the city area and analysis of land cover and land use. Particular attention was paid to above-average and extreme processes. The discussed morphogenetic processes included the analysis of floods on the Warta River flowing through the city, flash floods generated in the city streets, mass movements occurring mainly on the slopes of the Warta River valley and on the slopes of moraine hills, and wind erosion occurring in vast areas devoid of vegetation. Most of these processes are related to the progressive climatic changes and sealing of the ground by concreting and asphalting large patches of the city. The analysed processes are visualised on a geomorphological map and a land cover and land use map. Contemporary morphogenetic processes observed in Poznań include: (a) on morainic hills/uplands: mass movements, wind erosion and flash floods; (b) on outwash plains: mass movements and flash floods; (c) on fluvial landforms: mass movements and river floods; (d) within plains of different origin: flash floods. Increasing urbanisation of the city, mainly through the increase in impervious surfaces, increases the risk of flash floods, which have replaced river floods in the list of risks to urban infrastructure.</p>