Sensing the Submerged Landscape of Nisida Roman Harbour in the Gulf of Naples from Integrated Measurements on a USV

Abstract

This paper shows an interesting case of coastal landscape reconstruction by using innovative marine robotic instrumentation, applied to an archaeological key-site in the Campi Flegrei (Italy), one of the more inhabited areas in the Mediterranean during the Roman period. This active volcanic area is world famous for the ancient coastal cities of Baiae, Puteoli, and Misenum, places of military and commercial excellence. The multidisciplinary study of the submerged Roman harbour at Nisida Island was aimed at reconstructing the natural and anthropogenic underwater landscape by elaborating a multiscale dataset. The integrated marine surveys were carried out by an Unmanned Surface Vehicle (USV) foreseeing the simultaneous use of geophysical and photogrammetric sensors according to the modern philosophy of multi-modal mapping. All instrumental measurements were validated by on-site measurements performed by specialised scuba divers. The multiscale analysis of the sensing data allowed a precise reconstruction of the coastal morpho-evolutive trend and the relative sea level variation in the last 2000 years by means of a new type of archaeological sea-level marker here proposed for the first time. Furthermore, it provided a detailed multidimensional documentation of the underwater cultural heritage and a useful tool for evaluating the conservation state of archaeological submerged structures.

A Detailed Reconstruction of the Roman Landscape and the Submerged Archaeological Structure at “Castel dell’Ovo islet” (Naples, Southern Italy)

“…Like the famous Persian king Xerxes, Lucullus, Serses togatus, was able to cut the natural rock, to open sea-channels and to give a shape to landscape, complying with his wishes. Lush plantations of exotic species, cherry-trees, apricot-trees, imported from the East, together with wide artificial piscinae for the breeding of different fishes constitute only a part of the gigantic Lucullianum, a complex that could effectively be identified with the system Monte Echia/Megaris, but also with the villa on the islet of Nesis/Nisida like we argued recently [26,27]. The identification of the owner, however, is an enticing, but not the fundamental question: around the 1st century BC Megaris was certainly occupied by a magnificent villa maritima, owned by the wealthy Lucullus or by some other powerful member of the Roman senatorial aristocracy, that built his residence following the same principles.…”

“…Primarily, the depths were referred to the vertical datum of mean sea level (MSL), correcting each measurement with respect to tidal height obtained from the tidal table of Naples provided by the Hydrographic Institute of the Navy. Secondarily, the depth measurement was corrected with respect to the transducer submersion, measured by the acoustic system for the draught measuring [26]. Finally, the data were interpolated-by using a Topo to Raster interpolator-in order to obtain the detailed seabed bathymetry.…”

Seven Good Reasons for Integrating Terrestrial and Marine Spatial Datasets in Changing Environments

“…Benjamin et al [38]; Benjamin et al [58]; Furlani and Martin [40]; Mattei et al [59]; Sturt et al [60]; Veth et al [61] 4…”

Methodology for Performing Territorial Sea Baseline Measurements in Selected Waterbodies of Poland

“…Performing classical hydrographic measurements with manned vessels might prove impossible due to the excessively large draft of the vessels and echo sounder transducers installed on their bows. Therefore, according to the authors it seems optimal to use USVs for baseline measurements [31][32][33][34][35][36]. An alternative method is the use of manned or unmanned aerial vehicles equipped with LiDAR to determine the baseline.…”