Coastal Restoration Trust of New Zealand

Coastal Dune Ecosystem Reference Database

Using historic satellite and 3D UAV imagery to map the dynamics of the coast at sites with anthropogenic debris in Southland, New Zealand - Thesis summary Thesis

Author
Newman, C.
Year
2022
Publisher / Organisation
Auckland University of Technology
Pages
23
Summary
The coast is a naturally active margin that forms an important barrier system subjected to the forces of both the terrestrial and marine environment. Coastal erosion has become a problem where infrastructure such as roads and anthropogenic debris like coastal landfill are being exposed and subsequently consumed by the ocean. The overall aim of this research was to investigate the ability of a generalised GIS (Geographical Information System) methodology to quantify coastal dynamics at different locations with anthropogenic debris. The GIS methodology used compares historic satellite imagery as well as 3D seasonal UAV (Unmanned Aerial Vehicle) imagery to see where and how changes are occurring. This study investigated four sites along the southern coast of the South Island, New Zealand: Monkey Island, Colac Bay, Fortrose, and Porpoise Bay. Historic satellite imagery was used to investigate coastal dynamics by assessing the magnitude and rate of change occurring from past shorelines. Patterns were interpreted to make predictions about where the shorelines will be in the future. 3D UAV imagery was collected to analyse volumetric change on a seasonal basis. The main findings illustrate the influence of human intervention, such as how rip rap or anthropogenic debris can change the patterns occurring along the coast compared to a natural coastline. Seasonal 3D UAV imagery and analysis highlights both the great deal of temporal and spatial change in these environments, as well as the complexity of understanding the dynamics of coastal areas. This study evaluates the validity of applying a generalised GIS methodology and makes recommendations for further research, which will, in turn, inform future monitoring and management of coastlines with anthropogenic debris.