Computer-Aided Geomorphic Seabed Classification and Habitat Mapping at Punta Licosa MPA, Southern Italy

Abstract

Accurate seafloor maps serve as a critical component for understanding marine ecosystems and are essential for marine spatial planning, management of submerged cultural heritage and hazard risk assessments. In September 2001 the Marine Protected Area (MPA) of Punta Licosa has been mapped using a multibeam echosounder (MBES) and a side scan sonar (SSS) system in support of the Geosed project. Such seabed investigations has allowed for high-resolution bathymetric measurements and acoustic seafloor characterization through backscatter imagery. Based on visual interpretation of the data, the present study utilized a computer-aided seabed classification approach to map marine landform features and seabed composition of the study area. The results were then translated into a complete coverage geomorphologic map of the area to define benthic habitats. Offshore shelf plain make up more than half of the region (52.2%), with the terraces making up another 10.2% of the total area. Slopes make up a cumulative 30.1% of the study area. Scarp features comprise 4.3% while ridge features reach only 3.2% of the total study area. Benefits of the computer-aided seabed classification approach used in this study consisted in a fairly accurate geomorphic classification, while the effectiveness of a semi-automated approach for identifying substrate composition from backscatter data mostly relied on the level of acoustic artefacts present within the survey area.