Recruitment and Patch Establishment by Seed in the Seagrass Posidonia oceanica : Importance and Conservation Implications

• Published in: Frontiers in plant science 2017-06, Vol.8, p.1067
• Main Authors: Balestri, Elena, Vallerini, Flavia, Lardicci, Claudio
• Format: Article
• Language: English
• Subjects: global change; meadow conservation; Plant Science; Posidonia; seagrass; seed dispersal; sexual recruitment
• ISSN: 1664-462X; 1664-462X
• DOI: 10.3389/fpls.2017.01067

Seagrasses are declining globally, and deeper understanding is needed on the recruitment potential and distribution of new populations for many threatened species to support conservation planning in the face of climate change. Recruitment of , a threatened seagrass endemic to the Mediterranean, has long been considered rare due to infrequent flowering, but mounting evidence demonstrates that the species is responding to a changing climate through greater reproductive effort. Due to the fragmentary information on recruit occurrence and distribution, little is known about reproductive success in the species and its contribution to persistence. We assembled recruitment data from published and unpublished sources, including our own, to examine the frequency and extent of recruitment events (establishment of seedlings in a site), seedling growth potential and habitat characteristics at recruitment sites. Results show that at least one recruitment event has occurred about every 3 years, and 18 localities were colonized at least one time since the first seedling record in 1986. Notably, consistently high seedling inputs were observed in four localities of the Western Mediterranean. Seedlings established mainly on unoccupied substrate areas along the coasts of islands, in sheltered sites and at shallower depths (