The consideration of biological processes in hydro- and morphodynamic models is an important challenge for numerical simulation in coastal engineering. Eco-hydraulic aspects will play a major role in engineering tools and planning processes for the design of coastal works. Vegetation greatly affects the hydro- and morphodynamic models in coastal zones. Most hydrodynamic numerical models do not consider influences by ecological factors.
This paper focuses on the presentation of an object-oriented holistic framework for eco-hydraulic simulation. The numerical approximation is performed by a stabilized finite element method for hydro- and morphodynamic processes, to solve the related partial differential equations, and by a cell-oriented model for the simulation of ecological processes, which is based on a fuzzy rule system. The fundamental differences between these model paradigms require special transfer and coupling methods. Case studies on seagrass prediction in the North Sea around the island of Sylt show the main effects and influences on changed hydro- and morphodynamic processes and demonstrate the applicability of the coupled finite element fuzzy cell-based approach in eco-hydraulic modeling.