Banquette

The beaching of plant biomass, mainly leaves of Posidonia oceanica - endemic marine plant of the Mediterranean Sea - is a natural phenomenon. The structured and permanent deposits of beached Posidonia leaves are called banquettes and play an important role in protecting beaches from erosion, but they also give a both direct and indirect contribution to the biocoenosis of the beach-dune systems. Since the mid-twentieth century, the use of beaches for tourist industry has led to the removal of banquettes, as plant remains are mistakenly considered a negative externality by both managers and tourists. Nevertheless, the removing of beached plant biomass (banquettes or unstructured accumulations) from their natural location, imply the elimination not only of the sand mixed with the plant biomass, but also of a significant component of the beach structure, accelerating erosion and compromising the integrity of coastal habitat. This in turn forces local administrations to carry out important and costly interventions of coastal protection and artificial beach nourishment.

To overcome this procedure, expensive and not ecologically sustainable, we collaborated with ISPRA on the BARGAIN project, funded by the Lazio Region (Call for Knowledge and Cooperation for a New Development Model; LR 13/2008 - art.4) to define a pilot model for the management of plant biomass, the ecological beach, exportable on a national and international scale. This management model of the beached Posidonia biomass avoids its disposal in landfills and, just in the case that it is impossible to keep it on site, promotes its reuse according to principles of circular economy and protection of coastal ecosystems.

 

Scarpato A., Borrello P., Chiesa S., Devoti S.,  Magaletti E., Manfra L., Mugnai C., Parlagreco L., Piermarini R., Rotini A., Silvestri C., Cappucci S., Creo C., Migliore L., Mazzarelli G. (2020) - LA SPIAGGIA ECOLOGICA: GESTIONE SOSTENIBILE DELLA BANQUETTE DI POSIDONIA OCEANICA SUGLI ARENILI DEL LAZIO. ISPRA, Manuali e Linee Guida 192/2020. ISBN 978-88-448-1005-4 ONLINE https://www.isprambiente.gov.it/it/pubblicazioni/manuali-e-linee-guida/la-spiaggia-ecologica-gestione-sostenibile-della-banquette-di-posidonia-oceanica-sugli-arenili-del-lazio

Rotini A., Chiesa S., Manfra L., Borrello P., Piermarini R., Silvestri C., Cappucci S., Parlagreco L., Devoti S., Pisapia M., Creo C., Mezzetti T., Scarpato A., Migliore L. (2020). EFFECTIVENESS OF THE “ECOLOGICAL BEACH” MODEL: BENEFICIAL MANAGEMENT OF POSIDONIA BEACH CASTS AND BANQUETTE. Water, 12(11): 3238. DOI: 10.3390/w12113238 

The accumulation of Posidonia oceanica dead leaves on the beaches of the Mediterranean shores is a natural phenomenon. They are either temporary or permanent structures (banquettes) and represent a valuable resource, with important ecosystem functions including coastal protection against erosion. Nevertheless, the perception of these plant accumulations by the different stakeholders (beach managers, local administrations and tourists) is often negative; they consider these deposits a malevolent waste to be removed, rather than a natural and valuable component of the coastline. We propose an integrated/beneficial management model for posidonia deposits, called Ecological Beach, firstly proposed in France, and recently implemented and applied in Italy. The model promotes the preservation of posidonia beach casts on site, with a balanced coexistence of natural and anthropic elements. The model fosters the several important ecosystem services of the beach casts and contributes to coastal preservation. To successfully spread the model, several activities must be implemented: a regulatory framework, the collection of data about the occurrence of beach casts, management protocols and educational programs. The most important activity is the educational one, based on the dissemination of the ecological and economic value of the beach casts, aimed at switching the perception of this phenomenon towards positive appraisal.