Capart, HervéMassart, EstelleChevillard, CorentineCorentineChevillard2025-05-142025-05-142025-05-142024https://hdl.handle.net/2078.2/37766In steep valleys of mountainous regions, civil infrastructures are threatened by changes in the river bed elevation due to rainfall and landslides. The objective of this thesis is to propose a new model of the evolution of the river bed elevation. The elevation changes are modeled with a diffusion equation having a stochastic source term representing the sediment load from tributaries. The migration of the tributaries is represented as a random walk and its properties are derived. To account for rainfall variability, the model is modulated by a hydrologic time. An analytical and a numerical solution are derived for this model. Model calibration is performed using rainfall data and aerial images for the hydrologic time and the parameters of the migrating source.Diffusion equationStochastic processGamma-subordinated Ornstein-Ulhenbeck processRiver aggradationtext::thesis::master thesisthesis:46156