Seafloor habitat mapping on the "Pelagie Islands" MPA (Sicily Channel) using Remote Sensing Object Image Analysis supported by multibeam bathymetry and ground-truth data

Abstract

In this work, the seabed mapping of the shallow-water areas of Lampedusa, Lampione and Linosa, belonging to the "Pelagie Islands" Marine Protected Area, is presented. Three surveys were carried out (namely "Lampedusa2015", "Linosa2016" and "BioGeoLin") to collect bathymetric and acoustic backscatter data through the use of a Reson SeaBat 7125 high-resolution multibeam system. Ground-truth data, in the form of grab samples and diver video-observations, were also collected during the surveys. Sediment samples were analyzed for grain size, while video images were analyzed and described revealing the acoustic seabed and other bio-physical characteristics. Three seabed classification maps, including sediment types and seagrass distribution, were produced using Remote Sensing Object Based Image Analysis by integrating information derived from backscatter data and bathy-morphological features, validated by ground-truth data. The seabed maps, including sediment types and habitat distribution, contribute to the knowledge of the peculiar marine ecosystem observed at the islands.