A multidisciplinary approach for sustainable management of a complex coastal plain: The case of Sibari Plain (Southern Italy)

Coastal plain environments constantly adapt to change as a result of natural processes and increasing anthropogenic pressure, as in the case of the low relief Sibari coastal plain (Calabria, southern Italy). In order to reconstruct the hydrostratigraphic framework and explain the spatial distribution of groundwater salinization of the Sibari coastal plain, an integrated hydrogeological and geochemical approach was applied to support an accurate conceptualisation and modelling of the whole plain groundwater system. Litho-hydro-stratigraphic relationships were constructed from lithologic logs obtained from exploratory boreholes whereas, the groundwater flow system has been studied using conventional hydrogeological field investigations, hydrochemistry, and isotope hydrology. Three distinct Hydrological units (HU3-shallow aquifer, HU2 aquitard and HU1-lower aquifer) were identified showing distinct geometrical, hydrochemical and isotopic signatures. With the aim of explain the origin of Na-Cl, Ca-Cl and Na-HCO3 waters were considered the role of ion exchange processes. The results demonstrate that values of Na+, Mg2+, Cl and SO4 can be attributed to seawater intrusion, where K+ is probably the major pollutant of the shallow aquifer. The adopted multidisciplinary approach provides an effective tool for accurately determination of groundwater processes and can be useful for a sustainable management of water resources in coastal plain. The physically based model of the pail groundwater system was able to explain the observed groundwater salinity variations and to support a detailed long-lasting numerical simulation of variations in the quantity and quality of groundwater resources.