State-of-the-art: parametrization of hydrological and mechanical reinforcement effects of vegetation in slope stability models for shallow landslides

Abstract The use of vegetation as a Nature-based Solution (NbS) for shallow landslide risk reduction is receiving increased attention in the scientific community. Vegetation can contribute to slope stability through both hydrological and mechanical processes. Slope stability models are valuable tools to quantify the performance of vegetation management as a slope stabilizing measure. The aim of this study is to provide a comprehensive overview of how both the mechanical and hydrological effects of vegetation are parametrized in existing slope stability models. To this end, a systematic review of the peer-reviewed literature published between January 2000 and June 2023 is conducted. The review has shown that existing slope stability models that include effects of vegetation, do so with various degrees of complexity with regard to how accurately they attempt to mimic the physical processes present in nature. There is a need for further validation of existing models, especially extended to areas in the global south and in colder regions. Moreover, studies of time dependency in vegetation reinforcement capabilities are lacking, an aspect which is especially important in the light of climate change. This review provides valuable guidance for researchers and practitioners in their choice of appropriate slope stability models for their studies.