Posidonia oceanica meadows and the accumulations of dead leaves along Mediterranean shorelines, known as banquettes, are key components of coastal ecosystems, providing multiple ecological functions and ecosystem services. These deposits contribute to shoreline stabilization, mitigate erosion processes, and support biodiversity at the land–sea interface. Despite their ecological importance, banquettes are often perceived as a nuisance for tourism and are frequently removed to maintain the aesthetic appeal of recreational beaches, resulting in environmental impacts, including altered beach morphology, biodiversity loss, and increased beach-cleaning costs.

To support the sustainable management of P. oceanica banquettes as a nature-based solution for coastal protection, it is essential to improve our understanding of their spatial distribution, spatio-temporal dynamics, persistence patterns, and potential role as sinks and vectors of contaminants.

Here, we present a multidisciplinary monitoring framework that combines geospatial analysis, remote sensing, and field-based investigations. Specifically, we: (i) developed a GIS-based inventory of P. oceanica banquette occurrence across Mediterranean coastlines by integrating spatial information on beach-cast deposits with environmental and management-related geospatial layers, including seagrass meadow distribution, beach-use intensity, and protected areas; (ii) applied remote sensing and geospatial analyses to detect banquettes, quantify their spatial extent, and assess their temporal recurrence in selected pilot areas along the Italian coastline; and (iii) conducted field surveys to characterize banquette morphology and composition and evaluate their potential role as sinks and vectors of emerging contaminants, including microplastics.

The results represent a first step toward the development of a spatially explicit, basin-scale monitoring framework for P. oceanica banquettes in the Mediterranean Sea. Such an approach can support evidence-based coastal management, improve ecosystem service assessments, and inform conservation and restoration strategies aimed at enhancing the resilience of Mediterranean coastal socio-ecological systems.