Exploring the impact of human interventions on landslide dynamics evolution

Landslides are socio-natural hazards that are highly influenced by the interactions between physical processes and human interventions on slopes. There are several factors that can influence landslide occurrence, such as urbanization, environmental degradation, changes in land use and hydrological changes. The region of Lower Austria (Austria) is a great example of the interplay between historical land use changes and physical factors, such as geology and topography that increase landslide susceptibility and threaten important infrastructure. In recent decades, there have been a number of human interventions and land use changes that make it difficult to understand landslide dynamics. Therefore, a long-term monitoring system has been established since 2015 to better understand the spatio-temporal behaviour of landslides in this region. The Hofermühle sub-catchment, a district of Waidhofen an der Ybbs in Lower Austria, is an example of the interaction between human intervention and physical processes on slopes. The first recorded activity dates from the late 1970s and was followed by the installation of drainages and some significant land use changes. In 2013, a heavy rainfall reactivated a landslide that led to an earth-to-mudflow process downstream. This event was followed by a series of measures such as the installation of several surface and subsurface drainage systems. The aim of this study is to investigate the role of environmental changes such as deforestation and drainage on landslide evolution using long-term monitoring data, field measurements, and numerical modeling. The compilation of historical aerial photographs and meteorological data was used to better understand the conditions and triggering mechanisms that led to these past events. To understand post-failure landslide evolution and the anthropogenic impact on complex landslides, numerical models integrating long-term monitoring data and field-based measurements are used.