Dynamics of the Basilicata Ionian coast: human and natural drivers

Starting from the second half of the twentieth century, the Ionian coast of the Basilicata Region (southern Italy) has shown a progressive retreat. The analysis of the shoreline variations covering a time lapse of about 150 years has been carried out over the last 20 years according with the evolution of technology over time, so using various data sources and methods, as historical cartography, aerial and high-resolution (HR) satellites images, and Global Position System (GPS) surveys. The results of the analyses have proven to be helpful in describing the coastal dynamics, driven by several factors, natural or human induced, with their own intensity and frequency or persistency. In the case of Basilicata Ionian coast, the main reason of the progressive retreat is found in the huge sedimentary budget deficit, coming from the repeated damming of four of the five rivers flowing towards the sea in the Ionian coastal stretch. Moreover, the long observation period allows reading the punctual response of the coastal environment to the severe human induced variations either in the catchment areas of the rivers, or at coastal works along an already stressed coastline.