Using Historic Satellite and 3D UAV Imagery to Map the Dynamics of the Coast at Sites with Anthropogenic Debris in Southland New Zealand
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 and debris along the shore are being consumed by the ocean. The overall aim of this research was to investigate the ability of a generalised GIS methodology to quantify coastal dynamics at different locations with anthropogenic debris. 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 extracting the magnitude and rate of change occurring from past shorelines where patterns were interpreted to predict 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 importance of human intervention when interpreting the dynamics occurring along the coast and predicting where the future shoreline could be. 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.