SAVE-C

The project brings together 14 partners from different Caribbean and metropolitan teams around the theme of massive sargassum strandings along the Caribbean coast. The various partners involved in the project are known to produce work of high scientific quality and have already been involved in fundamental and applied research projects aimed at understanding certain ecological and physiological processes and at enhancing the value of marine resources, in particular macroalgae. The partners are funded by various funding agencies:

– LEMAR – MIO – BOREA Caen : funded by the ANR

– BOREA-UA Guadeloupe: funded by the Région Guadeloupe

– L3MA-Martinique, BIODIVENV-Ifremer-Martinique: financed by the Territorial Community of Martinique

– CIRAD-Martinique, TMB-Martinique, EFINOR-Paimpol, ALGAIA-Saint Lô, LBCM-UBS, IRDL-UBS: funded by the ADEME

– the two foreign partners, CINVESTAV (Mexico) and UWI (Barbados) are self-funded as they are ineligible in the SARGASSES PAA 2019.

Human populations in the Caribbean region, have been suffering since 2011 from brown tides followed by significant sargassum strandings which have catastrophic consequences for benthic fauna and flora, for health and human activities. The objectives of the SAVE-C project are to obtain basic knowledge on the rafts and species of Sargassum, but also to change the perception of local populations towards massive strandings of Sargassum on coastal areas, transforming this nuisance into a valorization opportunity. This is a contribution to three themes of the SARGASSES 2019 PAA: Themes 1,3,4. The SAVE-C project will fill the knowledge gap on the ecological functioning of the shoreline raft and their threats in the Caribbean, but also propose a solution to turn stranding into socio-economic opportunities with a potential means to develop applications of the abundant macroalgal biomasses stranded on beaches.

Using a combination of field studies, ecological and physiological experiments and biotechnology the SAVE-C project will:

provide knowledge on the Sargassum species responsible for these strandings and on Sargassum rafts, real habitat hosting animal, plant and microbial communities.
to optimise the collection and storage of Sargassum biomass prior to its valorisation in two sectors, agriculture and biomaterials.
provide recommendations for the collection and valorisation of Sargassum biomass.

SAVE-C Concept_project

The project is broken down into 5 research actions (WPs).

Sargasso rafts from the “new Sargasso Sea” are an atypical habitat and knowledge of its ecology is virtually non-existent.

WP1 Diversity associated with rafts (Resp. Valérie MICHOTEY, MIO-IRD) : the diversity associated with the habitat will be studied (fauna, flora and microorganisms). This diversity will be studied by different approaches, morphological, molecular and also by acoustics. Environmental parameters (temperature, salinity, O₂, pH, arsenic, etc…) around and in the rafts will also be studied.
WP2 Trophic and chemical interactions between raft organisms (Resp. Charlotte DROMARD, BOREA-UA Guadeloupe) : we will study the functional ecology within Sargassum rafts in order to identify the interactions between organisms (i.e. algal-burrower, algal-microbiota interactions), its food web, but also the evolution of these interactions during strandings that lead to ecological disturbances on the local marine food webs.

A fundamental issue is the maintenance of Sargassum thalli in pelagic life, as opposed to the majority of Sargassum species that are benthic.

WP3 Influence of environmental conditions on the life cycle of Sargassum (Resp. Solène CONNAN, LEMAR-UBO): we will study the life cycle of Sargassum, from the growth of the fragments, their vegetative reproduction, their dispersal until their degradation, in relation with the water quality (oligotrophy in pelagic zones compared to the enrichment of the coastal environment, by continental and/or atmospheric inputs) and with contaminants (including arsenic).

Sargassum rafts and groundings represent a biomass to be valorised.

WP4 Collection and stabilisation of the raw material Sargassum (Resp. Benjamin LERONDEAU EFINOR-Paimpol and Jean-Louis LENOISELE IRDL-UBS): we will test strategies to collect, dry and use Sargassum biomass during periods of mass stranding. This huge raw material is known to degrade very quickly. We will then study different possibilities to stabilize this biomass and optimize its use taking into account the possible accumulation of arsenic in the algal tissues.
WP5 Eco-responsible extraction processes and biomass valorisation (Resp. Maud BENOIT ALGAIA-Saint Lô and Nathalie BOURGOUGNON LBCM-UBS): in the framework of the collaboration between industrial actors and academic partners, we will valorize algal biomass in 2 sectors: agriculture with the production of biopesticides/biostimulants and the biomaterials sector with the production of biocartons by combining algal polymers with fibers from Caribbean plants.