Chapter Mapping coastal vulnerability against erosion along the Alicante coastline, Spain

Abstract

The assessment of coastal vulnerability helps prioritize investments to increase coastal resilience. This work aims to map the vulnerability of a 12 km coastal stretch of the province of Alicante, Spain. It is an area where natural spaces with wetlands and important dune ridges alternate with highly urbanized spots. The method calculates a Coastal Vulnerability Index (CVI) through three main indicators: geomorphology (geology, coastal slope, erosion rate, beach width and dune width), hydrodynamics (significant wave height, mean tide range and flood level indicator) and vegetation variables (state of seagrass meadows, depth and width of these meadows and backshore area covered by vegetation). The coastal strip studied was divided into sections of 200 m, obtaining the CVI on each one. The vulnerability of each variable was evaluated from 1 (Very low) to 5 (Very high) and the overall CVI was obtained. The higher values of CVI were detected in the urbanized areas (41% of the sections). Dune ridges serve as barriers to flooding and reduce erosion. A sufficient beach width and slope are crucial to preventing flooding during extreme weather events.