Application of geographical information systems in the analysis of hydrological inputs to a shallow Mediterranean coastal aquifer

Contributions to the groundwater flow within the catchment domain are due to natural subsystems such as direct infiltration, recharge from surface networks and subsurface water flowing through the slopes. Groundwater quality is affected by such contributions in the case of surface water contamination; the space and time scales of the subsystems connections are investigated in the paper. As a distributed recharge evaluation is needed along the aquifer boundaries for providing inputs to traditional models, a distributed approach to the simulation of subsystems is proposed: GIS capabilities support the management of the large amount of information describing the catchment hydrology. Application of a hydrologically oriented GIS to the problem of recharge evaluation in the case of the Bisagno aquifer (Italy) is presented: procedures have been developed in order to link together different hydrological processes resulting into a subsurface flow model able to simulate the catchment contribution to the groundwater flow in the aquifer. -Authors