The Littoral Bottoms of Benidorm Island (Western Mediterranean Sea): Eco-Sedimentological Characterization Through Benthic Foraminifera

Abstract

Benidorm Island is one of the most relevant protected marine areas in the Province of Alicante (south-eastern Iberian Peninsula). Its bathymetric gradient and the structural complexity of the seabed make it an ideal place to analyse foraminifer assemblages considering depth and sediment type (particle size distribution). For this purpose, seven sampling sites representing the variety of littoral/sublittoral bottoms present have been sampled. The seabed sediment is composed mainly of gravelly sand with a high bioclastic content, abundant echinoderm fragments, sponge spicules, and bivalve and gastropod shell debris. We have documented a highly diverse community of benthic foraminifera dominated by epiphytic species. This work also examines the relation between depth (or open marine influence) and the planktonic foraminifer ratio, discussing the implications in the geological marine record. The distribution of some benthic foraminifer key species has been evaluated in this regard. The scuba dives performed also reveal possible environmental deterioration due to increased marine recreational activities, mostly scuba diving and boating. Finally, the littoral bottoms surrounding Benidorm Island would be an excellent area for future research using foraminifera as bio-indicators for monitoring environmental impacts on coastal regions.