This research project will demonstrate practical use of drone-based remote sensing platforms and sensors to monitor, map, and model coastal saltmarsh. This PhD is fully funded.
It will utilise and evaluate low-cost drone (UAV) platforms carrying miniaturised sensors to capture high-resolution multi-spectral and multi-temporal aerial imagery. This will allow mapping of saltmarsh vegetation communities, their spatial distribution, and change over both space and time. 3D models of saltmarsh will be created providing insight into the micro-topography of saltmarsh resulting from sediment erosion and accretion, and geo-visualisations will provide the basis to gain better knowledge and understanding about saltmarsh form and function.
Saltmarshes are intertidal areas of fine sediment transported by water and stabilised by vegetation. They play a major role in flood defence providing a dynamic buffer between land and sea as they dissipate high wave energy created during storm events. They also possess important conservation value due to the wide variety of plants and animals associated with them. Saltmarshes are currently threatened by a range of human impacts and sea-level rise that could inundate coastal saltmarshes, with the potential for rapid change and loss. Given the diverse range of threats, monitoring and mapping their condition is vital. Ground-based survey is difficult, and time consuming. Although collection of remotely sensed data has potential to provide information that is not always accessible through field observations, traditional remote sensing is currently very expensive, infrequently undertaken, and/or lacks precision. Advances in small drone platforms now make it possible to acquire high-resolution aerial photography as the basis to generate centimetre resolution 3D models of the surface.
This research will develop a robust methodology for the practical use of low-cost drones and sensors to acquire aerial data to accurately monitor and map the spatial structure and evolution of saltmarsh vegetation over time; determine saltmarsh elevation dynamics; monitor photosynthetic capacity, nitrogen content, and the physiological status of saltmarsh vegetation. Data collection will be conducted at selected saltmarsh sites around the Scottish coastline following consultation with experts to help optimise identification of hotspots where information is needed. UAV overflights of the sites will be conducted at regular intervals both during and over several months with a drone carrying a number of miniaturised sensors to acquire colour stereo-imagery. The flights will be undertaken at low-altitude to maximise the spatial resolution of the imagery. Ground Control Points will be surveyed at each site using either a ground-based or UAV mounted RTK/PPK GPS unit to ensure accuracy of the subsequent geo/ortho-correction of the imagery. Photogrammetric software will be used to generate a high-resolution Digital Terrain Model (DTM), Digital Surface Model (DSM), and ortho-mosaic of the saltmarsh sites. Digital Elevation Models of Difference (DOD) will be interpreted to establish where sediment change has occurred. On-screen digitising, image interpretation and classification techniques will be used to prepare maps of the vegetation communities, confirmed by using reference documentation and co-incident ground-truthing. The imagery and 3D model will subsequently form the basis for developing novel geo-visualisations of the saltmarsh sites (including the use of a Virtual Reality suite)
Candidate requirements
The candidate should have, or be expected to achieve, a UK honours degree at 2.i or above (or equivalent) in a relevant subject area (e.g. Geography, Coastal Management, Coastal Ecology, remote sensing, GIS, Digital Mapping and Surveying, UAVs). The successful candidate will be expected to start in October 2018.
Funding model
This 3.5 year studentship is funded jointly by the School of Geosciences, University of Aberdeen, and SAGES (Scottish Alliance for Geoscience, Environment and Society). The PhD is fully funded and includes an annual stipend for the student commensurate with current RCUK rates, payment of tuition fees, and a research training support grant. Applications will be accepted from international students provided that they agree to cover the difference between UK/EU and overseas tuition fees.
Application procedure
Applications for the studentship can be completed online at https://www.abdn.ac.uk/pgap/login.php, noting clearly the name of the lead supervisor (Dr David Green) and the project title (exactly as advertised) on the application form. Informal enquiries about the studentship are strongly encouraged in advance of making a full application. To make an enquiry, please send a copy of your cv and a short covering letter addressed to Dr Green at the following email address: d.r.green@abdn.ac.uk. The closing date for applications is 26 January 2018. Applications received after that date will not be considered