PhD thesis defense of Aurélie PORTAS
Aurélie PORTAS, PhD student at MAPIEM lab, under the supervision of:
- BRIAND Jean-François
- CULIOLI Gérald
- QUILIEN Nolwenn (FEM, Brest)
will defend her PhD thesis in Life and Health Sciences, specialty Marine Ecology on the topic:
on April 12th at 09:00AM, at the Amphitheatre of Building M, University of Toulon.
before a jury composed of :
- Mme Frédérique Viard, Directrice de recherche CNRS-ISE - Montpellier / Rapporteure
- M. Cédric Hubas, Professeur des universités, MNHN / Rapporteur
- Mme Agnès Bouchez, Directrice de recherche INRAE, Thonon-les Bains / Examinatrice
- M. Antoine Carlier, Cadre de recherche, Ifremer - Brest / Examinateur
- M. Jean-François Briand, Maître de conférences, HDR-Université de Toulon / Directeur de thèse
- M. Gérald Culioli, Professeur des universités, Université d’Avignon / Co-directeur de thèse
- Mme Nolwenn Quillien, Chargée de recherche-FEM - Plouzané / Co-encadrante de thèse
Abstract
Biofouling is a process at the origin of many adverse effects in the field of marine renewable energy (MRE) where the effects and extent of biocolonization are still unknown. Within the framework of the ABIOP+ project, the objective of this thesis was to better understand the colonization mechanisms specific to MRE sites. The diversity and composition of eukaryotic communities were first evaluated through different molecular approaches in order to detect the widest range of taxa from samples collected in several contrasting marine environments. Secondly, this thesis focused on the factors influencing the colonization dynamics of biofouling communities, in particular the effect of hydrodynamics. An in situ and semi-controlled approach was carried out by evaluating the responses of the communities to different hydrodynamic conditions. For this, a multi-scale characterization of the biofilms thus formed was undertaken via complementary approaches linking metabarcoding (prokaryotes and eukaryotes), non-targeted metabolomics, biochemical assays and microscopy. Finally, we studied the eukaryotic communities in different EMR sites in the Atlantic and Mediterranean submerged between 3 and 24 months. Measurements of general biofouling characteristics (biomass, biovolume, density, ...) and molecular taxonomy approaches revealed differences in eukaryotic communities.
Keywords
biofouling, metabarcoding, hydrodynamics, spatio-temporal monitoring
