Assessing the conservation status of Posidonia oceanica at Tremiti Archipelago (Adriatic Sea): A comparative analysis of different classification systems

Posidonia oceanica meadows are fundamental coastal habitats currently affected by human disturbances. In the last decades, monitoring efforts have led to the development of several Ecological Indexes aiming to synthetically assess the health state of the meadows. Since different indexes including specific sets of metrics are used by different research groups and adopted by different countries throughout the Mediterranean basin, it is now important to understand their performances when classifying the Ecological Status of the meadows. Based on data collected within national monitoring programs targeting P. oceanica at Tremiti Islands Marine Protected Area (Adriatic Sea), here we calculated and compared the four most recent Ecological Indexes currently available. Our study revealed high consistency and comparability between indexes, highlighting the pros and cons of each one, and proving that they can be effectively used to monitor the conservation status of P. oceanica meadows.