Salt marsh species shift on the Zimmermanpolder marsh, Western Scheldt, the Netherlands
Other staff involved:
- ir. Jesse Bootsma (ET-MFS)
Vegetated intertidal aras, such as saltmarshes and mangroves, are dynamic ecosystems, that are decreasing in spatial extent worldwide. These areas provide crucial ecosystem services, including reduction of wave and current energy, sediment trapping, erosion control and carbon sequestration. Over time, changes in vegetation species, density, and extent can alter the shape of these intertidal zones. The feedbacks between hydrodynamics, sediment dynamics, morphology, and vegetation, known as biogeomorphological feedbacks, play a key role in these processes
In the Western Scheldt estuary, the Netherlands, several of these vegetated intertidal areas are present. Next to the villages Bath and Rilland, there is the Zimmermanpolder marsh (also known as Rilland or Bath). At this location, brackisch water is present due to the influence of the discharge of the Scheldt river and the impact by the tides from the North Sea. Spartina anglica dominated the marsh, but today, Bolboschoenus maritimus and Phragmites australis are prevalent. The construction of the sluice of Bath in the 1980s is hypothesized as a potential driver of this shift, but no in-depth studies have been conducted to date.
The main objective of this study would be to assess the dominant drivers for the species shift observed on the Zimmermanpolder marsh in the Dutch Western Scheldt. Understanding the drivers of species shifts is important for managing and restoring intertidal areas, which are vital for biodiversity, coastal protection and carbon sequestration. To enhance our understanding of the interaction between changing environmental conditions and saltmarsh vegetation species, we propose to combine vegetation data from readily available vegetation maps and environmental data (either from measurement stations, remote sensing or model output). Examples of environmental data to include are: salinity measurements, discharge through the sluices of Bath, elevation maps and/or inundation maps. The results of this study could inform saltmarsh management and restoration, as well as providing input for modelling efforts on dynamic vegetation modelling of saltmarshes.