Assessment of the anthropic impact on the shoreline evolution in Follonica (Italy) from 1973 to 2023 and future trends using GIS

Coastal erosion is a significant environmental and socio-economic issue that has affected shorelines globally since the mid-19th century. Shoreline degradation and instability threaten property, businesses, and human life, requiring effective marine governance and engineering interventions. Understanding coastal change is essential for the efficient monitoring and management of the coastal areas, mitigating the impacts related to the shoreline retreat. This thesis focuses on the coastline of Follonica, located in the Gulf of Follonica (Tuscany, Italy), following its evolution from 1973 to 2023 and predicting the future scenario up to 2040. Aerial images provided by Regione Toscana and from Google Earth Pro have been analysed to evaluate historical erosive and sedimentation trends, considering the different anthropic structures built along the coast over time. Then, the Leatherman’s Model has been used to predict the effects of climate change on the coastline. The projections are based on future climate change scenarios provided by the IPCC, focusing on the impact of sea-level rise. The significant anthropogenic alterations, driven by urban expansion and the tourism industry, has been also consider in the evaluation of the urbanization coefficient. These interventions have notably influenced sediment transport and erosive processes, highlighting the need for adaptive planning strategies. The results show a clear trend of escalating anthropogenic impact, in which submerged breakwaters have contributed to a more homogeneous and stable coastal profile. The future projections indicate significant sediment accumulation all over the study area, except for a small area northward of Molo Pratoranieri. In particular, the area at most risk appears to be the one on both sides of Fosso Cervia, where heavy sedimentation trends, that will overcome the protection structures are expected. The study suggests the importance of a reduction in hard defences and emphasize the advantages of softer, adaptive measures. The success of submerged breakwaters in stabilizing the coastline without inducing severe morphological changes suggests that similar strategies could be beneficial in other coastal areas. This approach aligns with nowadays coastal management principles, focused on resilience and ecological sustainability.