Moreover, flooding caused by sea level rise (Carbognin et al., 2010) is currently

threatening the historical city of Venice, so much so that major construction of mobile barriers at the lagoon inlets is ongoing (MOSE project, Magistrato alle Acque, 1997). These changes at the inlets affect substantially the lagoon environment (Tambroni and Seminara, 2006 and Ghezzo et al., 2010). This study focuses on the central part of the bottom of the lagoon directly surrounding the city of Venice in order to answer the following questions: First, what was the landscape of the central lagoon before Smad inhibitor the first human settlements? Second, what were the consequences of the major river diversions? Third, what were the consequences of dredging new navigation channels during the last century? Historically, the shallowness of the lagoon (average depth about 0.8 m) has prevented the use of acoustic/seismic Hydroxychloroquine nmr methods that are generally implemented for the reconstruction of ancient landscapes. Acoustical/seismic surveys were carried out only recently in the northern and southern lagoon (McClennen et al., 1997, McClennen and Housley, 2006, Madricardo et al., 2007, Madricardo et al., 2012, Zecchin et al., 2008, Zecchin et al., 2009, Tosi et al., 2009 and Rizzetto et al., 2009), while passive and controlled source seismic surveys were undertaken in the historical

center of Venice (Boaga et al., 2010). We conducted an extensive geophysical survey between 2003 and 2009 with very high spatial resolution (Madricardo et al., 2007 and Madricardo et al., 2012), given the general complexity and the horizontal variability SB-3CT of the sedimentary architecture in lagoon environments (Allen et al., 2006). We aimed to reconstruct the main sedimentary features within the lagoon sediments (like ancient salt marshes, buried creeks and palaeochannel patterns) to map ancient landscapes before and after the human intervention. By using the acoustical exploration combined with the extraction of cores and sedimentological, radiometric and micropalaeontological analyses, as well as comparison with historical maps, we were able to extract different time slices

of the lagoon’s evolution. The lagoon of Venice is located at the northern end of the Adriatic Sea. It has a surface area of 550 km2 and is the largest coastal lagoon in the Mediterranean. The lagoon has an average depth of less than 1 m and it is separated from the sea by barrier islands with three inlets. The main morphological features are intertidal and submerged mudflats, salt marshes, channels, creeks and islands. The lagoon formed as a consequence of the Flandrian marine transgression, when the sea reached its maximum ingression flooding the alluvial palaeo-plain that occupied the northern epicontinental Adriatic shelf. During the marine transgression, several barrier-lagoon systems formed in progressively more inland positions (Trincardi et al., 1994, Trincardi et al., 1996, Correggiari et al., 1996 and Storms et al., 2008).