Sediment Connectivity of Estuaries around the World

Abstract:

We quantify and interpret sediment pathways in four estuaries in the Netherlands and the United States using a connectivity analysis framework. In a connectivity framework, complex coastal systems are schematized as connected networks of sediment transport pathways. We apply graph theory and network analysis techniques to quantify the sediment dynamics and identify relevant patterns and exchange mechanisms. We apply and extend the concepts of Pearson et al (Preprint: https://doi.org/10.1002/essoar.10502451.1) by quantifying sediment connectivity of the Wadden Sea (the Netherlands), Western Scheldt (NL), San Francisco Bay (US), and Columbia River (US). These systems span diverse morphologies and hydrodynamic forcings, but we can use asymmetry, modularity, degree, strength, and centrality metrics to characterize and intercompare them. This connectivity analysis is built on output from numerical simulations, and we explore the advantages and disadvantages of Eulerian and Lagrangian modelling approaches. We conclude that connectivity analysis provides an effective approach to visualize and inter-compare sediment transport pathways in estuarine systems. For individual systems, the framework is a useful tool for planning human interventions such as nourishments, disposal of dredged material, or predicting the fate of contaminated sediment.