Detection of Marine Debris in Salt Marshes Using UAV Based Multispectral Images

Saltmarshes are critical coastal ecosystems that are increasingly threatened by the accumulation of marine and terrestrial debris, including plastics, metals, wood, and other anthropogenic litter. This search focuses on a UAV based remote sensing framework for detecting and isolating such debris within saltmarsh environments by masking out natural background elements such as vegetation, soil, and water. High resolution multispectral was collected using a DJI Matrice 300 UAV equipped with an AGROWING Alpha 7R Sextuple camera and ground truthed via vegetation quadrats at Derrymore Island, Ireland. Spectral indices including NDVI, GNDVI, and MNDWI were employed to generate binary masks for key land cover types, enabling precise identification of anomalous debris. The proposed method demonstrates a scalable, noninvasive and semiautomated approach to debris detection in complex saltmarsh terrains. Results demonstrate high accuracy in debris detection and classification, highlighting UAV based multispectral imaging as an efficient, accurate, and scalable approach for environmental monitoring and marine debris assessment in sensitive coastal ecosystems.