Taxonomical characterization of Posidonia oceanica banquettes and driftwoods-related fauna

The proposed work provide a multilevel approach for two beach-related allocthonous inputs: P. oceanica banquettes and driftwoods. Since beaches are commonly perceived as true deserts, their biological values and their ecological importance are often underestimated leading even more inadequate management strategies. Banquettes - more related to seasonal cycles of P. oceanica - have been studied through coil sampling and Berlese-Tullgren extraction, focusing mainly on the infaunal arthropods. Fauna associated to driftwoods has been surveyed through pitfall trapping, aiming to study more surface related organisms. The taxonomical characterization has been followed by estimation of species richness according to the most recent frameworks, to provide an insight to these high-diverse biocenosis inferring meaningful differences within and between sampled sites. The observed diversity has been characterized through a qualitative as well as quantitative approach. Three widely used ecological index, as well as Collembola lifeforms have been applied to study the composition and the structure of beach related fauna. Moreover, as shoreline environments undergo increasing anthropocentric pressure resulting from demographic growth and recreational-only oriented management, the response of the studied fauna to several environmental factors has been analysed through linear models and community composition analysis. The number of observed species is not directly related to the individual abundance recorded for each site.The observed - and often underestimated - taxonomical richness is determined by socalled rare species, which carry most of the diversity information. Nevertheless the composition of the observed communities change in time and space under the combined effects of several enviromental variables.