The research is aimed at describing and evaluating the role of the biodiversity of the macrobenthic peracarid crustaceans in the structure and functioning of the Antarctic Coastal and Shelf Ecosystem (ACSE), in the framework of a better understanding of the consequences of environmental changes on this ecosystem. Specific objectives are: -To characterize the structural aspects of the peracarid biodiversity (faunal composition, geographic and bathymetric distribution, habitats and microhabitats, bio-ecological traits) as well as their spatial and temporal variations. -To develop new synthetic tools for the assessment of the biodiversity of the Southern Ocean crustaceans, in particular an "Antarctic Marine Biodiversity Reference Centre" devoted to Amphipoda and new conventional and computer-assisted identification guides. -To evaluate the ecofunctional role of the peracarid crustacean taxocoenoses in the production and resilience of the benthic communities of the ACSE.