1ECOMAR - Laboratoire d'Ecologie Marine (Faculté des Sciences et Technologies - Université de la Réunion 15, avenue René Cassin - CS 92003 97744 Saint Denis Cédex 9 La Réunion - France)
Abstract : Regeneration of artificially induced lesions was monitored in nubbins of the branching coral Acropora muricata at two reef-flat sites representing contrasting environments at Réunion Island (21u079S, 55u329E). Growth of these injured nubbins was examined in parallel, and compared to controls. Biochemical compositions of the holobiont and the zooxanthellae density were determined at the onset of the experiment, and the photosynthetic efficiency (F v /F m) of zooxanthellae was monitored during the experiment. Acropora muricata rapidly regenerated small lesions, but regeneration rates significantly differed between sites. At the sheltered site characterized by high temperatures, temperature variations, and irradiance levels, regeneration took 192 days on average. At the exposed site, characterized by steadier temperatures and lower irradiation, nubbins demonstrated fast lesion repair (81 days), slower growth, lower zooxanthellae density, chlorophyll a concentration and lipid content than at the former site. A trade-off between growth and regeneration rates was evident here. High growth rates seem to impair regeneration capacity. We show that environmental conditions conducive to high zooxanthellae densities in corals are related to fast skeletal growth but also to reduced lesion regeneration rates. We hypothesize that a lowered regenerative capacity may be related to limited availability of energetic and cellular resources, consequences of coral holobionts operating at high levels of photosynthesis and associated growth.
https://hal.univ-reunion.fr/hal-01369712 Contributor : Gaël PotinConnect in order to contact the contributor Submitted on : Wednesday, September 21, 2016 - 2:17:11 PM Last modification on : Thursday, March 17, 2022 - 2:00:13 PM Long-term archiving on: : Thursday, December 22, 2016 - 1:16:33 PM
Vianney Denis, Mireille Guillaume, Madeleine Goutx, Stéphane de Palmas, Julien Debreuil, et al.. Fast Growth May Impair Regeneration Capacity in the Branching Coral Acropora muricata. PLoS ONE, Public Library of Science, 2013, 8 (8), pp.e72618. ⟨10.1371/journal.pone.0072618⟩. ⟨hal-01369712⟩