Environmental issues of the Island of Giglio, Tuscan Archipelago, Italy

Abstract

The Island of Giglio consists of the lower Pliocene monzogranite intrusion (91.5% of the territory) and Mesozoic–lower Miocene metamorphic and sedimentary tectonic units (8.5% of the territory) of the Ligurian-Piemontese and Tuscan domains in the Franco Promontory. Climatic data recorded from 1993 to 2015 highlight that the average annual temperature and rainfall have increased overall. The main morphological characteristics of the island are: (1) the landslides that affect either the geological formations, above all along the coastal belt, in particular in the Franco Promontory, or the widespread eluvium–colluvium deposits and numerous piles of rock blocks originating from the monzogranite intrusion; (2) the several torrents that cut across the monzogranite intrusion with high gradients resulting in considerable erosion. The island, which includes some very small perennial springs, is covered mainly by short brush and garrigue and subordinately by forests. Six environmental issues have been detected: the high geomorphological and hydraulic risk, respectively, along the coastline, and in the urban areas of Cala delle Cannelle, Giglio Campese, and Giglio Porto; the abandoned quarries showing unstable fronts; the landfill of municipal solid waste, lacking remediation aimed at its safety; the protection and set up of the perennial springs; the safety of paths; and the mining of pyrite started in 1875 until the closure of works in 1962. Suitable suggestions to solve the environmental issues are provided.