PHYSIOLOGICAL RESPONSES OF INTERTIDAL MACROALGAE TO OCEAN AND ATMOSPHERIC WARMING

The biological assemblages of European temperate coasts show significant climate change impacts, and several canopy-forming algae with their southern limit in the NW Iberian Peninsula are experiencing range contractions. We investigate the thermal responses of two brown algae species, both distributed along the Eastern North Atlantic coast and sharing similar distribution patterns, that differ in their intertidal positions: Pelvetia canaliculata (upper intertidal) and Fucus serratus (lower intertidal). We also explored phenotypic/adaptive differences in thermal response between the southernmost (NW Iberian Peninsula) and northern populations (Scotland) of the species. By means of physiological experiments in mesocosms and air chambers we investigated how a gradient of 12 sea surface temperature and 2 air temperature treatments affect the growth and mortality of these algae. We applied chlorophyll fluorescence (Imaging Pam), respirometry, and C:N ratio analyses to estimate the combined effects of temperature and desiccation. The results of our ecophysiological experiments will allow us to infer local extinctions and drastic modifications in intertidal communities in response to climate change.

Primary Presenter: Rosa Chefaoui, Universidad Rey Juan Carlos (rosa.chefaoui@urjc.es)

Authors:

Rosa Chefaoui, Universidad Rey Juan Carlos  (rosa.chefaoui@urjc.es)

Ana Ramírez-Lizán, Universidad Rey Juan Carlos  (ana.ramirez.lizan@urjc.es)

Marta Martins, CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental  (marta.martins@ciimar.up.pt)

Ismael Zarouali, Universidad Rey Juan Carlos  (i.zarouali.2017@alumnos.urjc.es)

Rosa Viejo, Universidad Rey Juan Carlos  (rosa.viejo@urjc.es)

Brezo Martínez, Universidad Rey Juan Carlos  (brezo.martinez@urjc.es)

João Serôdio, University of Aveiro  (jserodio@ua.pt)

Francisco Arenas, CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental  (farenas@ciimar.up.pt)