Le aree carsiche di rilevante interesse idrogeologico, ambientale e paesaggistico della Liguria (Italia)

The Ligurian Regional Law no. 14/1990 contributed to the understanding, development and protection of the karst ecosystems. Furthermore, it allowed the identification of regional karstic areas as well as the drawing of the related rules concerning land planning and management. The Regional Law no. 39/2009, also concerning geodiversity, has stressed the importance of karst aquifers protection: an updating of the karst areas map is required to this purpose. With the aim to fulfil the tasks defined with the new regional law, this paper discusses the followed methodology in order to update karst areas mapping. A summary of the obtained results after more than two decades from the issuing of the regional rules regarding speleology is provided as well. The starting point is represented by the regional caves cadastre; the first step towards the redefinition of karst areas can be obtained through the introduction of information layers concerning soluble rock formations, which can be provided by the regional geological mapping project data base. This redefinition will be divided into a first level according to the hydrogeological tectonic units, and in a second according to geographical location. From the overlap of these information 18 hydrogeological complex were obtained, 5 in not strictly carbonate rock masses. These new hydrogeological complexes will be then better contoured and further divided, according to lithology, karst hydrogeology and geomorphology, also distinguishing the recharge areas from the karst spring zones. This last activity is directly required by the guidelines stated by the new regional law, which plans to define a peculiar regulatory regime modulated on the intrinsic vulnerability of the different areas, to ensure better protection of karst systems and their aquifers.