Biogeomorphic self-organization of intertidal wetlands

Intertidal landscapes are complex environments located between the land and sea, and which are regularly flooded by tides. They provide highly valuable ecosystem services, but are threatened by sea level rise and, in some places, decreasing sediment supply. Previous studies showed that the small-scale (order of square meters) interactions between vegetation dynamics, water flow and sediment transport (so-called biogeomorphic feedbacks) have a great impact on channel network formation and evolution at the landscape-scale (order of square kilometers). This process is called biogeomorphic self-organization.

The aim of this project is to investigate the impact of various biotic (e.g. plant species traits) and abiotic characteristics (e.g. tidal amplitude) on biogeomorphic self-organization of intertidal landscapes. More specifically, we hypothesize that (1) different conditions lead to the self-organization of different channel network patterns, and (2) the resulting self-organized landscape structures determine the efficiency to distribute and trap sediments on the intertidal floodplain, and hence the resilience of the landscape to sea level rise and decreasing sediment supply.

By using a combination of numerical simulations, field observations and flume experiments, we aim at producing new fundamental knowledge on landscape self-organization by biogeomorphic feedbacks, and its implications for the resilience of intertidal landscapes against environmental changes.

Tidal marsh channel seascape in Cadiz Bay Natural Park, Spain. Source: https://doi.org/10.3354/meps09051

Related publications

C. Schwarz, O. Gourgue, J. van Belzen, Z. Zhu, T.J. Bouma, J. Van de Koppel, G. Ruessink, N. Claude and S. Temmerman. Self-organization of a biogeomorphic landscape controlled by plant life-history traits. Nature Geoscience, 11:672-677, 2018.
https://dx.doi.org/10.1038/s41561-018-0180-y

O. Gourgue, J. van Belzen, C. Schwarz, T.J. Bouma, J. van de Koppel, S. Temmerman. A convolution method to assess subgrid-scale interactions between flow and patchy vegetation in biogeomorphic models. Journal of Advances in Modeling Earth Systems, accepted for publication.
https://doi.org/10.1029/2020MS002116

And more to come…

In collaboration with

Sergio Fagherazzi (Boston University, MA, USA)
Stijn Temmerman (University of Antwerp, Belgium)