| Direct and indirect methods were used for mapping Posidonia oceanica beds around Elba Island. Side scan sonar and a visual infra red scanner were used to detect the extension of beds. Also, direct observations were adopted to assess the bed density and to calibrate the indirect methods. Samples of P. oceanica were collected and phenological variables and macroalgal epiphytes were studied to assess the health of the beds. P. oceanica around Elba Island covered an area of 3 680 ha. The largest beds occupied the four main gulfs of the island, characterized by gentle slopes and sandy bottoms. There, the beds showed uniform cover while a patchy structure was common on the rocky and steep bottoms of the western and south-eastern coasts of the island. P. oceanica... |
