Lead Supervisor: Jonathan Dale, Department of Geography and Environmental Science, University of Reading
Co-supervisor: Steve Robinson, Department of Geography and Environmental Science, University of Reading; Avidesh Seenath; School of Geography and the Environment, University of Oxford
Saltmarsh provides important ecosystem services including habitat for wading and migratory birds, nursery grounds of commercial fish species, carbon storage and flood defence through wave attenuation. Stimulating saltmarsh growth may improve the local level of flood protection, reducing the need for costly engineering works to sea walls and other defences, whilst also increasing the provision of other services. This is particularly important at locations where there is a need to restore and compensate for the loss of saltmarsh due to erosion caused by sea level rise, land claim and a reduction in sediment supply. One method of encouraging marsh growth is through the construction of sedimentation polders, typically out of brushwood fencing, to reduce current velocities and wave heights and increase sedimentation rates. However, little is known of the change in the sediment regime at these sites following polder construction, and subsequently the influence on ecosystem service delivery, and the effect of fence design on the evolution of the site.
This project will provide a new insight into the vegetation and sediment properties of the saltmarsh inside and outside of sedimentation polders. Saltmarsh development following the (re)construction of brushwood fencing will also be assessed at Rumney Great Wharf, Seven Estuary, where brushwood fencing was constructed between 1999 and 2005 but was not maintained and the brushwood eroded away with only the fence posts remaining. During 2024, the brushwood will be re-implemented and extended, with this project evaluating the subsequent evolution of the site. This will include repeat measurements of the sediment properties, vegetation, the deployment of equipment to monitor site hydrodynamics and multispectral Uncrewed Aerial System surveys. From these surveys, methods of using vegetation indices and remote sensing techniques to evaluate the change in vegetated areas in the site will be developed. Datasets will then be used to develop, calibrate, and validate a process-based numerical model to provide novel predictions of the meso-scale (50 to 100 year) evolution of the site, and to evaluate the possible changes in design required to encourage further saltmarsh growth and ecosystem service delivery.
Working in partnership with Natural Resources Wales, the findings from this study will inform the location, design and maintenance of future sedimentation polder schemes; implemented as a nature-based solution and adaption approach to improve local flood defence standards, whilst restoring intertidal habitat and compensating for losses elsewhere. Results will also be used to evaluate the maintenance required at Rumney Great Wharf and other pre-existing schemes.
There will be the opportunity for training in field work, lab work, programming and numerical modelling. A placement with Natural Resources Wales may be offered, and there will be the chance to visit Natural Resources Wales offices to disseminate findings and discuss your research. You will also be encouraged to engage in Department of Geography and Environmental Science meetings and events to integrate into the wider research community at the University of Reading.
This project would be suitable for students with a degree in Geography or Environmental Science or a closely related environmental or physical science. A range of methods and approaches will be used during the study. The student must be willing to undertake extensive fieldwork in a muddy intertidal environment, whilst also having skills or a willingness to learn laboratory, programming, and modelling skills.
This project has CASE support from Natural Resources Wales