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This paper presents new bathymetric data acquired around Linosa Island, in the Pelagie Archipelago, revealing the submarine extension of the volcanic edifice, more wide and complex than previously known. The seafloor of Linosa, from the coastal area to about 1000 m depth, was mapped with multibeam systems during the ‘Linosa 2016’ and ‘BioGeoLin 2017’ surveys. A bathymetric map of the surveyed area (about 298 km2) was drawn at the original 1:30,000 scale. Overall, the submarine portions of Linosa extend on a total area of about 159 km2 and are preferentially developed in a NW-SE direction, in agreement with the regional main tectonic trend in the area. The new bathymetric data allow to recognize different sectors in the submarine extension of the volcanic edifice where constructional (volcanic) activity alternates with erosive-depositional processes affecting the submarine flanks of the island.

We present the first seabed map of the shallow-water areas of Lampione, the islet of to the Pelagie Islands Marine Protected Area (Sicily Channel, Italy). The seafloor was mapped from the coast to about a depth of 75 m using high-resolution multibeam systems (both for bathymetry and backscatter) along with ground-truth data in the form of grab samples and ROV video-observations. The map was produced using Remotely Sensing Object Based Image Analysis by integrating information derived from multibeam system, validated by ground-truth data. The resulting 1: 5.000 scale map includes sediment types and habitat distribution contributing to the knowledge of the peculiar marine ecosystem observed at Lampione, that will be checked and implemented through further surveys. In particular, the map provides the first indication of the occurrence of rhodolith/maërl habitats at Lampione, which are among the most important ecosystems in the Mediterranean Sea.

In this paper we present the seabed maps of the shallow-water areas of Lampedusa and Linosa, belonging to the Pelagie Islands Marine Protected Area. Two surveys were carried out (“Lampedusa 2015” and “Linosa 2016”) 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 both surveys. Sediment samples were analyzed for grain size, while video images were analyzed and described revealing the acoustic seabed and other bio-physical characteristics. A map of seabed classification, including sediment types and seagrass distribution, was produced using the tool Remote Sensing Object Based Image Analysis (RSOBIA) by integrating information derived from backscatter data and bathy-morphological features, validated by ground-truth data. This allows to create a first seabed maps (i.e. benthoscape classification), of Lampedusa and Linosa, at scale 1:20 000 and 1:32 000, respectively, that will be checked and implemented through further surveys. The results point out a very rich and largely variable marine ecosystem on the seabed surrounding the two islands, with the occurrence of priority habitats, and will be of support for a more comprehensive maritime spatial planning of the Marine Protected Area.