The quantitative description of soil water movement at the plot scale and beyond remains an open challenge. At the plot scale the mathematical description of soil water movement is typically based on the Richards equation. It is process-based, but already comes with model errors through fundamental limitations such as the local equilibrium assumption. The application of Richards’ equation to larger scales is then additionally limited by the intrinsic multiscale heterogeneity of soils and the consequently lacking information about heterogeneous soil hydraulic material properties in combination with the highly non-linear processes.
In this talk, I will first discuss the strengths and limitations of Richards’ equation and will demonstrate how data assimilation tools can be used to achieve a consistent aggregation of available information in the presence of model errors on a small example at the plot scale. Then I will present my recent research at the Biosphere 2 Landscape Evolution Observatory (LEO), which offers a unique opportunity to apply process-based modeling to larger scales and investigate the impact of heterogeneity and the possibilities to represent heterogeneity at the hillslope scale.
Dr. Hannes H. Bauser is a postdoctoral fellow at Biosphere 2 at the University of Arizona. He received his PhD in Physics from Heidelberg University, Germany, for his work on Knowledge Fusion in Soil Hydrology. In 2019, Hannes was granted a research fellowship by the German Research Foundation (DFG) and joined the U of A for his project on Process-based modeling of soil hydrology and its verification at the Biosphere 2 Landscape Evolution Observatory.