Marine Biodiversity in a Coastal Periphery Revealed by a Community-Based Monitoring Approach Integrating Citizen Science and Environmental DNA Metabarcoding

The global biodiversity crisis brings significant environmental and social impacts, necessitating innovative approaches to achieve the Sustainable Development Goals. This is particularly relevant for coastal peripheries that are rich in both natural and cultural capital. The Reknotting Marine Biodiversity project adopted a trans-disciplinary approach to integrate participatory science and education, involving local communities and researchers in biodiversity monitoring using environmental DNA metabarcoding along the coast of Marina di Camerota, Southern Italy. This approach compared Posidonia oceanica habitats with areas subject to anthropogenic pressures. Results show a greater diversity of pelagic fish and benthic organisms in the presence of P. oceanica, nine species that can potentially cause Harmful Algal Blooms (HABs), and eight species responsible for non-toxic algal blooms in less pristine areas. This study highlights the value of coastal habitats and the strategic value of citizen science in raising ecological awareness, proposing a replicable model for local marine observatories jointly managed by scientists and citizens.