Modelling soil compaction associated to marsh restoration in the Venice Lagoon

Salt marshes are characteristic landforms of the Venice Lagoon, Italy, but are largely present in transitional environments worldwide. Over the past decades they drastically declined and, only more recently, in-depth studies have demonstrated how much important is their preservation. Salt marshes host a high biodiversity with several ecosystem services, and perform important functions for the protection of coastal areas, reducing the risk of floods and erosion. A significant percentage of salt marshes within the Venice Lagoon disappeared due to the superposition of several causes such as a deficit in the sediment balance between leaving and entering the lagoon, land subsidence, rise of the mean sea level (msl), and increased wave intensity due to ship and boat traffic. To contrast this trend, a large plan of salt marsh restoration through artificial nourishment was undertaken in the whole lagoon since the 1970s using sediments made available by canal dredging. This thesis aims to investigate the mentioned processes in the evolution of the platform elevation of Le Sorelle-B salt marsh, an artificial marsh under construction in the central basin of the Venice Lagoon (Italy). The study is carried out using an advanced three-dimensional geomechanical simulator (NATSUB3D) and a set of geological, geomechanical, and topographical measurements carried out in the study area.