SAVE-C Study of holopelagic SArgassum responsible of massive beachings: Valorization & Ecology on Caribbean coasts - IRD
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Atelier SARGASSES – MTES – Meeting en distanciel, 29 janvier 2021
SAVE-C
Study of holopelagic SArgassum responsible of massive beachings:
Valorization & Ecology on Caribbean coasts
Valérie STIGER-POUVREAU (LEMAR-IUEM-UBO)
Consortium
7 partners:
7 partners:
Caribbean areas
Metropolitan France
P2
P4
P6 P11
P1
P8
P9
P10
P5 P13
P7 P14
P12 P3
LEMAR-IUEM-UBO, Wikipedia, LEMAR-IUEM-UBO
Recherche
fondamentale
SAVE-C (2020-2023)
Recherche appliquée
LEMAR-IUEM-UBO
Différentes échelles d’étude
Guyane => Antilles => Mexique Au large => Baie => Echouement Radeau => Algue => Métabolites
Fig. 1. Sargassum sightings in Guadeloupe Island (French Antilles), from helicopter survey on 22nd May 2015 (Photos courtesy of F. Mazéas). 1–5: Guadeloupe. 6: Désirade. 7: Marie
Galante. 8–9 Les Saintes.
Each year, tons of algae accumulate on the exposed beaches of et al., 2014; Weis, 1968). These communities vary according to season,
windward coastlines in the Lesser Antilles (Fig. 1). Subsequently, the geographical area and age of the raft (Stoner and Greening, 1984). The
coastal environment is subjected to significant damages and non- presence of large quantities of Sargassum may also interfere and
survival of many organisms. During their trip the rafts of algae influence the sea-turtles’ choice of nesting sites. Sometimes, if the
accumulate a community of marine organisms composed of micro- algal biomass is excessive, turtles are unable to climb these obstacles
and macro-epiphytes, fungi, over hundred species of invertebrates and and will lay their eggs in the Sargassum (Williams and Feagin, 2010),
a.
fish, and four species of turtles (Colombini and Chelazzi, 2003; Huffard impacting reproductive effectiveness. Removal of algae from beaches
55
Fig. 1. Sargassum sightings in Guadeloupe Island (French Antilles), from helicopter survey on 22nd May 2015 (Photos courtesy of F. Mazéas). 1–5: Guadeloupe. 6: Désirade. 7: Marie
Galante. 8–9 Les Saintes.
Sargassum sightings in Guadeloupe Island (French Antilles), from helicopter survey on 22nd May 2015 (Photos courtesy of F. Mazéas). 1–5: Guadeloupe. 6: Désirade. 7: Marie
Each year, tons of algae accumulate on the exposed beaches of et al., 2014; Weis, 1968). These communities vary according to season,
e. 8–9 Les Saintes.
windward coastlines in the Lesser Wikipedia, F. Mazeas,
Antilles (Fig. in Marechal
1). Subsequently, the et al.geographical
(2017), M IO– IRDand
area – Univ.
age ofAix-Marseille
the raft (Stoner and Greening, 1984). The
coastal environment is subjected to significant damages and non- presence of large quantities of Sargassum may also interfere and
ch year, tons of algae accumulate on the exposed beaches
survival et al.,During
of manyoforganisms. 2014; their
Weis,trip1968). These
the rafts of communities
algae influencevarythe
according tochoice
sea-turtles’ season, of nesting sites. Sometimes, if the
ward coastlines in the Lesser Antilles (Fig. 1). Subsequently, the
accumulate a community geographical area and
of marine organisms age of of
composed themicro-
raft (Stoner
algal and Greening,
biomass 1984).
is excessive, The
turtles are unable to climb these obstacles
al environment is subjected to significant damages and macro-epiphytes,
and non- fungi, over hundred
presence speciesquantities
of large of invertebrates
of and
Sargassum and will lay their
may alsoeggs in the Sargassum
interfere and (Williams and Feagin, 2010),
fish, and four species of turtles (Colombini and Chelazzi, 2003; Huffard impacting reproductive effectiveness. Removal of algae from beaches
al of many organisms. During their trip the rafts of algae influence the sea-turtles’ choice of nesting sites. Sometimes, if the
mulate a community of marine organisms composed of micro- algal biomass is excessive, turtles are unable to climb these obstacles
macro-epiphytes, fungi, over hundred species of invertebrates and 55 (Williams and Feagin, 2010),
and will lay their eggs in the Sargassum
L’habitat Radeau de sargasses
• Quels organismes vivent dans l’habitat Radeau de Sargassum ?
• Comment varie cette diversité avec l’âge du radeau et lors de la dégradation des sargasses ?
• Actions de recherche :
• Caractérisation des radeaux et des masses d’eau environnante
• Identification des organismes présents dans les radeaux :
• Morphométrie
• Marqueurs moléculaires
Lien avec le Projet ORIGINS
• Marqueurs chimiques
• Acoustique
MIO – IRD – Univ. Aix-Marseille
L’habitat Radeau de sargasses
• Comment interagissent les organismes au sein d’un radeau?
• Ces interactions varient elles selon les deux gradients?
• A la côte, quel est impact des sargasses sur le milieu corallien?
• Actions de recherche :
• Etude du réseau trophique/métabolisme et variabilité spatio-temporelle
• Etude des interactions Algues/brouteurs et Algues/microbiote
• Etude des transferts d’N (dégradation des sargasses) en milieu corallien
MIO – IRD – Univ. Aix Marseille, F. Mazeas, in Marechal et al. (2017)
gs in Guadeloupe Island (French Antilles), from helicopter survey on 22nd May 2015 (Photos courtesy of F. Mazéas). 1–5: Guadeloupe. 6: Désirade. 7: M
Physiologie des sargasses
• Quelles stratégies ont développé les sargasses qui dérivent ?
• Que se passe-t-il lors de la dégradation des sargasses ?
• Comment l’algue concentre les contaminants (arsenic, …) ?
• Actions de recherche :
• Composition biochimique des sargasses et variabilités spatio-temporelles
• Etudes en conditions contrôlées + cages en mer :
• Maintien des sargasses dans la colonne d’eau (flottabilité, multiplication, ageage, …)
• Protection contre les radiations solaires et contre les microorganismes
Lien avec FORESEA
• Cinétique de pompage et accumulation de l’arsenic
LEMAR-IUEM-UBO
Valorisation des sargasses
• Comment et où collecter une biomasse de qualité?
• Comment conditionner cette biomasse en vue de la valoriser?
• Actions de recherche :
• Stratégies
oupe Island (French Antilles), from helicopter surveyde
on collecte
22nd May (Baie, au large)
2015 (Photos =>ofRecommandations
courtesy (collecte
F. Mazéas). 1–5: Guadeloupe. + engins
6: Désirade. de collecte)
7: Marie
• Décontamination et stabilisation de la biomasse collectée
ccumulate on the exposed beaches of et al., 2014; Weis, 1968). These communities vary according to season,
ser Antilles (Fig. 1). Subsequently, the geographical area and age of the raft (Stoner and Greening, 1984). The
ted to significant damages and non- presence of large quantities of Sargassum may also interfere and
During their trip the rafts of algae influence the sea-turtles’
F. Mazeas, choice
in Marechal et al. (2017), of nesting sites. Sometimes, if the
LEMAR-IUEM-UBO
marine organisms composed of micro- algal biomass is excessive, turtles are unable to climb these obstacles
er hundred species of invertebrates and and will lay their eggs in the Sargassum (Williams and Feagin, 2010),
(Colombini and Chelazzi, 2003; Huffard impacting reproductive effectiveness. Removal of algae from beaches
Valorisation des sargasses
• Peut on valoriser cette énorme biomasse de Sargassum ?
• Si oui, peut on adopter une stratégie d’économie circulaire?
• Actions de recherche :
• Utiliser des procédés éco-responsables, minimiser les déchets
• Produire des biostimulants/Biopesticides
• Produire des biocartons
CIRAD-Martinique, TMB-Martinique
Atelier SARGASSES – MTES – Meeting en distanciel, 29 janvier 2021
SAVE-C
Study of holopelagic SArgassum responsible of massive beachings:
Valorization & Ecology on Caribbean coasts
https://www-iuem.univ-brest.fr/lemar/projets-scientifiques/save-c/
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