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Nell'ambito dello studio dell'intrusione d'acqua salata nell'acquifero freatico costiero del Comune di Cervia, la creazione di una carta delle isofreatiche è stata particolarmente difficile a causa della mancanza di una topografia del territorio dettagliata e aggiornata e d'informazioni omogenee e recenti relativamente alla profondità della falda. Le uniche informazioni disponibili si riferiscono al rilievo topografico del 1978 e a dati freatimetrici relativi al 1994, troppo vecchi se si considera che l'area investigata si colloca in una zona con forti tassi di subsidenza (maggiore di 2 mm/anno) e caratterizzata da enormi trasformazioni indotte sia dalle opere di bonifica sia dall'enorme sviluppo urbanistico e turistico. Un nuovo rilievo topografico di dettaglio e il monitoraggio della falda su base GIS, hanno permesso di creare una carta delle isofreatiche aggiornata e precisa, da cui identificare e localizzare la presenza di acqua salata nell'acquifero superficiale. L'importanza della precisione topografica è stigmatizzata dal fatto che la profondità della superficie di separazione fra acque dolci e salate, secondo la legge di Ghyben-Herzberg, è circa 40 volte l'altezza del livello freatico sopra il livello del mare. Una errore di pochi centimetri nella stima di quest'altezza si traduce in un errore 40 volte superiore nella localizzazione della superficie di separazione. Molte delle quote topografiche nel nuovo rilievo si sono rilevate sotto il livello del mare o in prossimità di esso e le quote freatiche sono raramente, se non nelle zone dunari e nei mesi invernali, sopra il livello del mare. I nuovi rilievi sono consistenti con i dati di conducibilità elettrica che mostrano un acquifero prevalentemente salato. During the characterization of the Salt-water intrusion in the freatic aquifer of Cervia, we had many problems in reconstructing the water table maps, because of the lack of an updated topography of the territory The only available information refer to the topographical survey of 1978 and to water table depths data going back to 1994, too old considering that the investigated area is placed in a strong subsidence region (larger than 2 mm/year). A new detailed topographical survey and aquifer monitoring, integrated within a GIS, allowed to construct new precise and updated water table maps that characterize the actual condition of salt water intrusion in the aquifer. The importance of topographical precision stems from the fact that the salt water – fresh water interface depth, as stated by the Ghyben-Herzberg relationship, is approximately 40 times the height of water table above sea level. An error of a few centimeters in estimating this height translates in an error 40 times larger in estimating the saltwater/freshwater interface depth. Most of the topography in this area is now placed below sea level or in its proximity and the freatic level is very rarely above it. The new water table maps are consistent with the electric conductivity data that show an aquifer almost completely salty

Interdisciplinary and knowledge integration are widely applied concepts for decision-support within environmental management. The choice of an appropriate framework to support integrated assessment is an important step for the definition of the system being studied. The DPSIR (Driver-Pressure-State-Impact- Response) conceptual framework is one such tool which functions by addressing the cause-effect relationships between sectors of human activity and the environment, thus being ideal for anthropogenized natural environments as is the Bahia de Cádiz Nature Park. The paper describes how, supported by input from literature review and expert consultation, the framework may be used as an entry point for the definition of the significant D-P-S-I elements that characterize the study area, playing at different spatial and temporal ranges. Human health concepts are included, emphasizing its 'integrated' nature. Results demonstrate an interest in uncovering dynamics amongst drivers within the 'Sectors' and 'Infrastructure' groups; resulting changes within land-use patterns and hydrological modifications (pressures); their effects on the different land-types , geological and hydrological characteristics, vegetation and birdlife (states) and the effects of these on the different services (impacts) the park environment offers. Remote sensing, GIS technology and indicators are postulated as efficient analysis tools for applying to available aerial photos, satellite imagery and birdlife census data. Ultimately the framework hopes to serve as a conceptual base for future investigation within the scope of this project and beyond.

Dune characterization in coastal zones is important for planning coastal defenses, groundwater management, and tourism development. Dune protection should be one of the main goals of any Integrated Coastal Zone Management Plan (ICZM). Coastal dunes efficiently oppose saltwater intrusion: their topographic elevation and their excellent infiltration capacity provide freshwater recharge and a hydraulic head that protect from saline intrusion according to the Ghyben-Herzberg principle (Fetter, 2001). The lateral continuity of the dunes system is also important for creating a continuous freshwater lens along the coast. As part of the Interreg IIIc Beachmed – “PosiDune project”, a monitoring campaign for groundwater levels and quality is being conducted on some test sites along stretches of the Ravenna coast: P.to Corsini, Marina Romea, Marina di Ravenna, Bevano river mouth. Dunes are still preserved in these areas and they act as natural defenses against storms, erosion and wave attack (Caruso et al., 2004; Caruso et al. 2006). A monitoring network has been established in each test site by placing piezometers both on the back and the crest of the dune and by carrying out a VES (Vertical Electri Sounding) geophysical campaign. The two methods (giving the chance to compare direct – piezometers - and indirect – geoelectric - data) has allowed to characterize the thickness of the fresh groundwater lens and the depth of the freshwater-saltwater interface. These actions have been integrated using: 1. a G.I.S. for data management; 2. a topographic and bathymetric reconstruction of the area using a LIDAR (Light detection and Ranging) survey; 3. a systematic seasonal update of the topography base and geomorphology using DGPS and theodolite surveys; 4. a survey of the geomorphologic evolution of the area through the periodical (monthly) acquisition of aerial images (flight height at 300m). The techniques employed are aimed at a precise charactetrization of the morphologic and hydrogeologic framework of the study areas. In addition, the maintenance of the monitoring system in future years will allow a better understanding of the effects of vegetation, dune restoration, and climate change to coastal hydrology and to ecosystem development (Gabbianelli & Sangiorgi, 2004; Ranjan et al. 2006). A clear comprehension of the role of dunes, achieved with this project, will be helpful for the management of the sites studied, especially considering their naturalistic values and peculiarities (they all belong to the Ramsar Zones list, SIC/ZPS sites list, Regional Po Delta Park – Emilia Romagna Region areas)

The roman time S. Vitale forest near Ravenna represents an historical landmark in the Po Plain. Today, the forest is surrounded by the complex urban system of Ravenna, by the city industrial infrastructure, and by the waterworks of the agricultural drainage system. Several natural and anthropogenic features threaten this area: • Saltwater intrusion in the freatic aquifer and seawater encroachment inland along the rivers. • Natural and anthropogenic land subsidence (caused by gas and deep groundwater winning, mostly after 1950). • Direct contamination from water bodies open to sea. • Destruction of coastal dunes and reduction of its barrier effect. • Land reclamation drainage system. • Insufficient aquifer recharge. • Sea level rise. Land subsidence has dropped most of the territory below mean sea level and it has modified the river regime and the normal groundwater flow. A drainage system is necessary to lower the phreatic level and keep dry the agricultural land. A second objective of the drainage system is to keep above the watertable the roots of the trees in the coastal areas. The result of the drainage system management, however, is an unstable freatic aquifer that is not able to contrast saltwater intrusion and is not helping much to maintain healthy the pinewood forests, that are also very sensitive to salinity.

During the last few decades coastal dunes, for centuries a distinctive feature of Ravenna’s coastline, have been seriously affected by tourist development and human activities. Considering the importance of these structures as natural defences against beach erosion from sea storms, the main purpose of this work is to characterize the dunes and to reconstruct their recent evolution from both a botanical and a geo-environmental point of view. Another purpose is to evaluate the future natural evolution of dunes in this type of coast.

L'intenso sfruttameno dei depositi di sale sottostanti la città di Tuzla ha indotto vistosi fenomeni di subsidenza e di collassamento del terreno. A partire dal 2002 è stato effettuato un monitoraggio annuale DGPS e Remote Sensing

The basic aim of this work was to achieve a preliminary but integrated characterisation of an area of the Ravenna littoral coastline. The use of suitable computerised procedures has allowed the reconstruction of the morphological evolution of this area by means of historical and recent cartography. Coastal sediments were characterised by sampling 3 cores at about 2 km offshore. The following aspects were studied: 1) Mineralogical characterisation of both the total and the fine fraction of sediments by X-ray Diffraction. 2) Characterisation of sedimentary horizons by radiodating. 3)Magnetic susceptibility profiling. 4) Determination of some heavy metals (Cu, Pb, Zn, Cd) by anodic stripping voltammetry.