A Coastal Dune Vulnerability Classification. A Case Study of the SW Iberian Peninsula

Abstract

A coastal Dune Vulnerability Index (DVI) has been proposed which incorporates the system's condition according to geomorphological (GCD) and ecological (VC) resilience levels, together with aeolian (AI), marine (MI) and anthrogenic (HE) factors. The index computation allows quantification of the coastal dune vulnerability as well as highlighting the main source of imposed changes. The applied procedure in the SW Iberian Peninsula allowed spatial comparison among 30 dune systems and the zonation of coastal dune fields in contrasted management units. Cluster analysis suggested that four dune groupings could be differentiated for the case study area of the SW Iberian Peninsula. These were Group I dunes (low vulnerability, DVI < 0.25); Group II dunes (low to medium vulnerability; DVI 0.25 to 0.5); Group III dunes (medium to high vulnerability, DVI 0.5 to 0.6); and Group IV dunes (High vulnerability; DVI > 0.6). The DVI algorithm was: DVI = (GCD+VC+MI+HE+AI) /5. The related procedure gives an integrated coastal dune vulnerability assessment which allows zonation of coastal dunes in suitable management units. The procedure helps dune managers to focus management strategies at specific locations as it enables identification of both the potential vulnerability and the main source(s) of imposed change.