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located on the inner continental shelf between 19 and 50
           m depth; they represent very interesting features from
           an environmental and geological point of view and also
           for the ecology and marine biology of benthos. Seabed
           sediments on the continental shelf around Egadi Islands
           are mainly constituted by heterogeneous mixtures
           composed by pebbles and gravels with medium to
           coarse sands, rich in bioclasts [5].
           Among natural features of the sea bottom, as already
           mentioned,  Posidonia oceanica meadows are the
           most important biocoenoses for their abundance and
           distribution all around the islands. P. oceanica meadows
           are one of the most important Mediterranean ecosystems
           and represent a high-value habitat for both their
           ecological role and the associated biodiversity. Seagrass
           beds are a high-productivity ecosystem: they produce
           oxygen, represent a reproductive and nursery area for
           several species, reduce the energy of the currents and                                                    Research & development
           waves on the submerged beach, and contribute to the
           stability of the sea bottom and beach protection [6, 7].
           Moreover, the  coralligenous  community  represents  a    FIGURE 2   Location of 15 underwater itineraries at Favignana Island
           habitat of high ecological importance for the richness
           of associated biodiversity and landscape value, as
           well as the presence of valuable species of natural and
           conservation interest.

           Field work at Egadi Islands’ MPA

           In 2012 and 2013 some ENEA researchers explored 15
           underwater pathways at Favignana Island (Figure 2), 11
           at Marettimo (Figure 3) and two at Levanzo (Figure 4) by
           means of scuba diving.
           For each pathway, underwater photographs were taken
           by using a  NIKON D80 digital  camera  with SEA&SEA
           housing  equipped  with two SEA&SEA strobes.
           Underwater videos  were recorded using  a Sony full-
           HD video camera enclosed in an underwater housing
           with a wide-angle  lens  and two lamps. Information
           about species presence and distribution was recorded
           on underwater tablets. Only the conspicuous  species
           visually recognized during diving inspections  were
           reported; while  diving, voucher  specimens  were
           collected to help their identification. Sea temperature,
           depth, orientation and a sketch of each path were
           recorded too.                                       FIGURE 3   Location of 11 underwater itineraries at Marettimo Island

                                                                                  EAI    Energia, Ambiente e Innovazione    4/2015
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