|Vulnerabilities in tidal marsh development for coastal defence|
Bagde, S. (2019). Vulnerabilities in tidal marsh development for coastal defence
. Thesis. NIOZ Royal Netherlands Institute for Sea Research: Yerseke. 33 pp.
For my MSc internship, I decided to apply for a research internship at Royal Netherlands Institute for Sea Research (NIOZ), Yerseke. Here, I undertook an internship in the Estuarine and Delta Systems department, under the wilful guidance of Jim van Belzen. I worked under the umbrella of the Zeeland 2121 project, which is essentially focussed on developing coastal defence strategies through ecosystem-based solutions.The primary focus of my internship was examining the idea of the double-dike system as a viable coastal defence strategy. In this system, a tidal marsh would be recreated between two dikes. This marsh would be allowed regulated inundation so that develops elevation naturally – thus behaving the same way a natural salt marsh would. This idea is based on existing studies that have shown tidal marshes to be very resilient systems that are capable of withstanding environmental stressors to a large extent. To implement such a system, the area chosen would be between dikes on the coast and older pre-existing dikes.For my role in this project, I focussed on the development of tidal marshes over a period of a hundred years using a 1-D model based in Python. The model is designed to include the dynamic processes of tidal marsh development in order to capture parts of the complexities observed in natural marshes. To do so we created a model which includes dynamic interactions between hydrodynamic, geomorphic and biological processes in a tidal marsh system. Using this model, the ‘invulnerability’ of tidal marshes, and their ability to keep up with rising sea levels, is examined in this study.In the scope of the Zeeland 2121 project, the establishment of tidal marshes in the double dike system is the goal to develop resilient coastal defences. In such a context, it is important that the marshes that are developed in these double dike systems function in the way existing literature predicts. Since the initial phase of this project includes exploring possibilities for the establishment of such a defence strategy, this is an ideal timeframe to analyse the development of tidal marshes and the possible vulnerabilities this development could face in the duration of this project.Overview of internship activities:• Literature research on tidal marshes, strengths and vulnerabilities.• Site visits to uniquely developing tidal marsh systems.• Development of tidal marsh model incorporating dynamic nature of the processes involved in marsh development.• Modelling effect of different environmental stressors on marsh development• Interpretation of model results.• Producing insight on development strategies for tidal marshes.