Predicting growth and survival of holopelagic Sargassum using a mechanistic model under different environmental scenarios

Drifting holopelagic Sargassum morphotypes experience fluctuation in temperature and nutrient availability as they spread across the tropical Atlantic. Current studies have largely focused on the dispersion of this macroalga. However, accurately forecasting Sargassum morphotypes biomass distribution and stranding requires a deeper understanding of the trade-offs between environmental variable and organism functions such as growth, nutrient storage, and survival. Based on current knowledge of Sargassum morphotypes, a multi reserves DEB (Dynamic Energy Budget) theory is developed to simulate nutrient uptake and temperature response under different environmental conditions. Growth and survival based on nutrient availability and temperature scenarios encountered by Sargassum along their drift is  explicitly quantified by estimating species parameters, performing simulations, and comparing them with experimental studies.  As a part of the BIOMAS project (BIOenergetic Modeling Approach for Sargassum dynamics), the SargaDEB model will help in the estimation of Sargassum biomass and dispersion by integrating this model into a drift model in order to simulate Sargassum morphotypes proliferation on seasonal scale and through multiple years. Through this approach, we will gain understanding of the interplay between biological and physical factors that drive the dispersal and biomass proliferation of Sargassum to improve bloom predictions.  

Presentation Preference: Oral

Primary Presenter: Maria José Lagunes, MARBEC, LEMAR, IRD (maria_jose.lagunes@ird.fr)

Authors:

Maria-José Lagunes, MARBEC,LEMAR, IRD, Univ. Montpellier,CNRS, Ifremer  (maria_jose.lagunes@ird.fr)

Christophe Lett, MARBEC, IRD, Univ. Montpellier,CNRS, Ifremer  (christophe.lett@ird.fr)

Léo Berline, MIO, Aix Marseille Univ, Université de Toulon, CNRS, IRD  (leo.berline@mio.osupytheas.fr)

Evelyn R. Salas-Acosta, MIO, Aix Marseille Univ, Université de Toulon, CNRS, IRD. CINVESTAV, Applied Phycology Lab  (evelynraquel.salas@gmail.com)

Daniel Robledo, CINVESTAV, Applied Phycology Lab  (daniel.robledo@cinvestav.mx)

Román M. Vásquez-Elizondo, CINVESTAV, Applied Phycology Lab  (roman.vazquez@cinvestav.mx)

Thierry Thibaut, MIO, Aix Marseille Univ, Université de Toulon, CNRS, IRD  (thierry.thibaut@univ-amu.fr)

Laure Pecquerie, LEMAR, IRD, Univ Brest, CNRS, Ifremer, IUEM  (laure.pecquerie@ird.fr)