A geoelectrical survey was carried out in the Metapontum Forest Reserve located along the Ionian coast of the Basilicata region (Southern Italy). In this work we used the method of two-dimensional electrical resistivity tomography for obtaining high-resolution electrical images in the investigated site. In particular, three electrical resistivity tomography, all orthogonal to the coastline, in the investigated area were carried out. To complete and integrate the geophysical data, soil and groundwater samplings, seventeen and five, respectively, were analyzed using chemical physical techniques. Geoelectrical survey, supported by laboratory analysis of soil and water samples have revealed the presence of a process of saltwater in coastal Forest Reserve of Metapontum, which have caused the decline of the existing pine forest with the consequent erosion and desertification problems. The results have disclosed the way to identify and discriminate large areas affected by intensive soil salinization and high resolution electrical images of the subsurface electrical resistivity plays a key role in delineating the saltwater intrusion front in coastal areas. Furthermore, our integrated study represents a contribution to the future programs for the protection, planning, and management of the terrestrial and marine resources in this coastal area. 1. Introduction Coastal areas are of great environmental, economic, social, and cultural relevance. Therefore, the implementation of suitable monitoring and protection actions is fundamental for their preservation and for assuring future use of this resource. Such actions have to be based on an ecosystem perspective for preserving coastal environment integrity and functioning and for planning sustainable resource management of both marine and terrestrial components (EU Recommendation on Integrated Coastal Zone Management—ICZM—European Commission EC/413/2002). Post [1] has defined coastal aquifers as the subsurface equivalents of coastal areas where continental fresh groundwater and seawater meet. Coastal plains are often contaminated by salt waters and the process associated to the marine water entering an aquifer is generally called seawater intrusion. Different approaches have been adopted to estimate seawater intrusion. For example, many authors [2–5] have employed geochemical methods based on measures of electrical conductivity, of chloride concentration, and other cation and anion concentrations, parameters which generally highlight seawater contamination. Nowadays great attention is focused on innovative geophysical
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