Assessment of the Coastal Sensitivity Using the CS Index in the Gulf of Gabes Tunisia; Southern Mediterranean Coast

Abstract

Assessment of the coastal degradation using the coastal sensitivity index (CSI) in the microtidal environment (Gulf of Gabes, Tunisia) shows that 78.6% of the coast is under low to moderate sensitivity. Moderate sensitivity class includes the sheltered zones and the stable sea cliffs. The highest sensitivity was recorded in sandy beaches (12.7%) where the drift actions amplify littoral fragility and flood risk.The coastal sensitivity index (CSI) is resulted from the combination of eight ranked variables: (a) geomorphology (b) coastal slope (c) hinterland topography (d) facies (e) shoreline exposure (f) shoreline changes (g) tide (h) sea-level trend. Fifty six morphodynamic cells are deduced from a strictmorphologic classification of the studied coast. Each specified cell presents a numerical pattern according to the ranked physical and structural variables. Once managed, the beaches with the highest sensitivity are immediately disturbed. Littoral disturbance is irreversible when the foredune unit is damaged but sustainable remediation of coastal areas must emphasize with the adequate planning for the environmental rehabilitation.