benthic microalgae
BENTHIC MICROALGAE :
Benthic microalgae are photosynthetic microorganisms growing in the sediment, contrarily to phytoplankton that develop in the water column. The microphytobenthos can consist of diatoms, cyanobacteria, Chlorophyceae and/or flagellates. Among the diatoms, which largely dominate in intertidal mudflats of the Atlantic coasts, two types can be observed : the epipelic diatoms, which are motile, and the epipsammic diatoms, which are generally smaller and stick to sediment grains with mucilaginous secretions. Epipsammic diatoms generally dominate in the sandy and mixed sediments, while epipelic diatoms dominate in pure mud. These epipelic diatoms migrate to the sediment surface during diurnal low tides to realize the photosynthesis. Thirty-seven species of diatoms have been identified on the Brouage mudflat, which is one of the largest mudflats in the Marennes-Oléron bay.
BENTHIC MICROALGAE STUDIED IN THE TEAM BIOFEEL :
Most of the studies on benthic microalgae are carried out on intertidal bare mudflats, but some studies are also done on other soft-bottom coastal habitats, like seagrass beds, sandflats, and shallow subtidal embayments. Researchers from the team BIOFEEL focus their research on the primary production of benthic microalgae, especially on bare mudflats, by building models of primary production based on remote sensing. Another part of the studies aims at better assessing the role of the microphytobenthos as a food source for the meiofauna, the macrofauna, and for fish (i.e. mullets).
RESEARCH CARRIED OUT IN THE TEAM BIOFEEL ABOUT BENTHIC MICROALGAE :
Quantification of primary production based on modelling.
Determination of the role of benthic microalgae as a food source in the functioning of intertidal and subtidal habitats using trophic markers (stable isotopes, fatty acids).
RESEARCHERS FROM THE TEAM BIOFEEL WORKING ON BENTHIC MICROALGAE :
Christine Dupuy
Vincent Le Fouest
Benoit Lebreton
Raphaël Savelli
REFERENCE PUBLICATIONS :
- Blanchard G.F., 2006. Analyse conceptuelle du système de production primaire microphytobenthique des vasières intertidales. Océanis 32, 215-235.
- Kromkamp J.C., de Brouwer J.F.C., Blanchard G.F., Forster R., Créach V., 2006. Functioning of microphytobenthos in estuaries. Royal Academy of Arts and Sciences, Amsterdam, 262 p.
- MacIntyre H.L., Geider R.J., Miller D.C., 1996. Microphytobenthos : The ecological role of the "secret garden" of unvegetated, shallow-water marine habitats. I. Distribution, abundance and primary production. Estuaries 19, 186-201.
- Miller D.C., Geider R.J., MacIntyre H.L., 1996. Microphytobenthos : The ecological role of the Secret Garden of unvegetated, shallow-water marine habitats. II. Role in sediment stability and shallow-water food webs. Estuaries 19, 202-212.
- Round F.E., Crawford R.M., Mann D.G., 1990. The Diatoms : biology and morphology of the genera. Cambridge University Press, Cambridge, 747 p.
MAJOR PUBLICATIONS OF THE TEAM BIOFEEL :
- Blanchard G.F., Guarini J.-M., Orvain F., Sauriau P.-G., 2001. Dynamic behaviour of benthic microalgal biomass in intertidal mudflats. Journal of Experimental Marine Biology and Ecology 264, 85-100.
- Guarini J.-M., Blanchard G.F., Gros P., Gouleau D., Bacher C., 2000. Dynamic model of the short-term variability of microphytobenthic biomass on temperate intertidal mudflats. Marine Ecology Progress Series 195, 291-303.
- Haubois A.-G., Sylvestre F., Guarini J.-M., Richard P., Blanchard G.F., 2005. Spatio-temporal structure of the epipelic diatom assemblage from an intertidal mudflat in Marennes-Oléron Bay, France. Estuarine, Coastal and Shelf Science 64, 385-394.
- Herlory O., Guarini J.-M., Richard P., Blanchard G.F., 2004. Microstructure of microphytobenthic biofilm and its spatio-temporal dynamics in an intertidal mudflat (Aiguillon Bay, France). Marine Ecology Progress Series 282, 33-44.
- Lebreton B., Richard P., Galois R., Radenac G., Pfléger C., Guillou G., Mornet F., Blanchard G.F., 2011. Trophic importance of diatoms in an intertidal Zostera noltii seagrass bed : Evidence from stable isotope and fatty acid analyses. Estuarine, Coastal and Shelf Science 92, 140-153.
- Méléder V., Savelli R., Barnett A., Polsenaere P., Gernez P., Cugier P., Lerouxel A., Le Bris A., Dupuy C., Le Fouest V., Lavaud J., 2020. Mapping the intertidal microphytobenthos gross primary production, part I : Coupling multispectral remote sensing and physical modeling. Frontiers in Marine Science 7, 520.
- Riera P., Richard P., 1996. Isotopic determination of food sources of Crassostrea gigas along a trophic gradient in the estuarine bay of Marennes-Oléron. Estuarine, Coastal and Shelf Science 42, 347-360.
- Savelli R., Méléder V., Cugier P., Polsenaere P., Dupuy C., Lavaud J., Barnett A., Le Fouest V., 2020. Mapping the intertidal microphytobenthos gross Primary production, Part II : Merging remote sensing and physical-biological coupled modeling. Frontiers in Marine Science 7, 521
- van der Heijden L.H., Niquil N., Haraldsson M., Asmus R.M., Pacella S.R., Graeve M., Rzeznik-Orignac J., Asmus H., Saint-Béat B., Lebreton B., 2020. Quantitative food web modeling unravels the importance of the microphytobenthos-meiofauna pathway for a high trophic transfer by meiofauna in soft-bottom intertidal food webs. Ecological Modelling 430, 109129.