The influence of hillslope processes on large-scale landform evolution

• Applicant: Professor Dr. Stefan Hergarten
• Subject Area: Palaeontology ; Geophysics ; Physical Geography
• Term: from 2020 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 432703650

Landform evolution modeling has received growing interest not only in geomorphology over the last decades, but also in the context of tectonics and climate change. Most of the contemporary studies in this field refer to large-scale fluvial erosion where the established differential equations are not very complicated, and efficient numerical implementations have become available. In contrast, processes at the hillslope scale are more complex, and there is little consensus about appropriate modeling approaches.Although the susceptibility of hillslope processes to changes in climate and vegetation may be even higher than that of fluvial erosion, hillslope processes have been addressed in numerical models not very often. In particular, the interaction between hillslope processes and fluvial erosion has apparently been addressed only in a few studies. Fluvial erosion is a major long-term driver of hillslope processes. In turn, the delivery of sediments from the hillslopes to the rivers introduces a strong feedback. While hillslope processes in general reduce relief, this feedback increases the steepness of the rivers required for balancing uplift and may thus even increase the large-scale relief.The project attempts to quantify the interaction between hillslope processes and fluvial erosion with focus on large-scale landform evolution. Different modeling approaches ranging from the simplest linear diffusion equation to statistical, event-based landslide models will be implemented and investigated. Beyond quantifying the effect of these processes, focus will be on the question how the applicability of the different models under given conditions can be assessed by analyzing real topographies, and how the respective model parameters can be estimated.

• DFG Programme: Research Grants