[en] Following the unprecedented marine heatwaves of summer 2022, extensive flowering of the endemic seagrass Posidonia oceanica was witnessed across the western Mediterranean. To unravel the causes of this event, we conducted a pan-Mediterranean analysis across 442 sites spanning all Mediterranean ecoregions, with 76% exhibiting flowering. Flowering differed regionally, with both highest flowering prevalence (over 90%) and flowering intensity (up to 0.75) recorded in the Liguro-Provençal and Balearic Seas. We demonstrate that regions experiencing large summer sea surface temperature anomaly with high marine heatwave cumulative intensity displayed the highest flowering intensity. The probability of flowering was very likely when marine heatwave cumulative intensity exceeded ⁓120°C days. These findings suggest that marine heatwaves trigger flowering in P. oceanica and, given the high energetic cost of sexual reproduction, continued ocean warming may shift energy allocation toward flowering. This shift could profoundly affect the species’ reproductive strategies, posing major challenges and uncertainties for its long-term evolution.
Disciplines :
Environmental sciences & ecology
Author, co-author :
Astruch, Patrick
Bensoussan, Nathaniel
André, Serena
Boudouresque, Charles-François
Tomas, Fiona
Teixidó, Núria
Carlot, Jérémy
Belloni, Bruno
Garcia-Escudero, Catalina A.
Akçalı, Barış
Alcoverro, Teresa
Apostolaki, Eugenia T.
Badalamenti, Fabio
Boada, Jordi
Boulenger, Arnaud ; Université de Liège - ULiège > Freshwater and OCeanic science Unit of reSearch (FOCUS)
Cabral, Mélanie
Casoli, Edoardo
Chimienti, Giovanni
Estaque, Tristan
Fernández Torquemada, Yolanda
Gerakaris, Vasilis
Gobert, Sylvie ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Océanographie biologique
Grech, Daniele
Kletou, Demetris
Mačić, Vesna
Máñez-Crespo, Julia
Marco-Méndez, Candela
Molenaar, Heike
Moreno, Diego
Sánchez-Lizaso, José Luis
Schohn, Thomas
Terrados, Jorge
Torras Jorda, Georgina
Ventura, Daniele
Zenone, Arturo
Albalat-Oliver, Balma
Bardinal, Vincent
Barrajón Domenech, Agustín
Belgacem, Walid
Ben Souissi, Jamila
Bernardeau-Esteller, Jaime
Bianchi, Carlo Nike
Castejón, Inés
Cebrian, Emma
Charbonnel, Eric
Cheminée, Adrien
Chéré, Edouard
Chiarore, Antonia
Constantinou, George
Cottalorda, Jean-Michel
Cvitković, Ivan
D’Anna, Giovanni
Despalatović, Marija
Dokoza, Fedra
Fernández-Casado, Manuel
Ferrari, Bruno
Ghanem, Raouia
Guillemain, Dorian
Guillén Nieto, Juan Eduardo
Güresen, Aysu
Hartmann, Virginie
Hernandez, Noelia
Izquierdo, Muñoz Andres
Jakl, Zrinka
Jamme, Stéphane
Karayalı, Onur
Kleitou, Periklis
Kurtović Mrčelić, Jelena
Lazennec, Arthur
Lovat, Valentina
Mancini, Ilaria
Mancini, Gianluca
Marbà, Núria
Marengo, Michel ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Océanographie biologique
Michez, Noëmie
Mirasole, Alice
Monnier, Briac
Morri, Carla
Navarro-Martinez, Pedro C.
Oprandi, Alice
Pansini, Arianna
Pergent-Martini, Christine
Pey, Alexis
Piazzi, Luigi
Procaccini, Gabriele
Remón, José Miguel
Roberty, Stéphane ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Ecophysiologie et physiologie animale
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