title: 3D modeling of phytoplankton seasonal variation and nutrient budget in a southern Mediterranean Lagoon.
abstract: A 3D coupled physical-biogeochemical model is developed and applied to Bizerte Lagoon (Tunisia), in order to understand and quantitatively assess its hydrobiological functioning and nutrients budget. The biogeochemical module accounts for nitrogen and phosphorus and includes the water column and upper sediment layer. The simulations showed that water circulation and the seasonal patterns of nutrients, phytoplankton and dissolved oxygen were satisfactorily reproduced. Model results indicate that water circulation in the lagoon is driven mainly by tide and wind. Plankton primary production is co-limited by phosphorus and nitrogen, and is highest in the inner part of the lagoon, due to the combined effects of high water residence time and high nutrient inputs from the boundary. However, a sensitivity analysis highlights the importance of exchanges with the Mediterranean Sea in maintaining a high level of productivity. Intensive use of fertilizers in the catchment area has a significant effect on phytoplankton biomass increase.
authors.affiliation: Institut National des Sciences et Technologie de la Mer - 28, rue 2 mars 1934 - Salammbô 2025. Laboratoire Milieu Marin, Tunisie.
authors.forename: Béchir
authors.initials: B
authors.lastname: Béjaoui
authors.affiliation: Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, Borgo Grotta Gigante 42/c Sgonico, Italy.
authors.forename: Cosimo
authors.initials: C
authors.lastname: Solidoro
authors.affiliation: Institut National des Sciences et Technologie de la Mer - 28, rue 2 mars 1934 - Salammbô 2025. Laboratoire Milieu Marin, Tunisie.
authors.forename: Ali
authors.initials: A
authors.lastname: Harzallah
authors.affiliation: Aix-Marseille Université, CNRS/INSU, IRD, Mediterranean Institute of Oceanography (MIO), UM 110, 13288 Marseille, France; Université de Toulon, CNRS/INSU, IRD, Mediterranean Institute of Oceanography (MIO), UM 110, 83957 La Garde, France.
authors.forename: Cristèle
authors.initials: C
authors.lastname: Chevalier
authors.affiliation: IFREMER DYneco/Pelagos Brest, BP 70, 29280 Plouzané, France.
authors.forename: Annie
authors.initials: A
authors.lastname: Chapelle
authors.affiliation: Institut National des Sciences et Technologie de la Mer - 28, rue 2 mars 1934 - Salammbô 2025. Laboratoire Milieu Marin, Tunisie.
authors.forename: Noureddine
authors.initials: N
authors.lastname: Zaaboub
authors.affiliation: Université de Bourgogne Franche-Comté, Laboratoire de Chrono-Environnement, UMR CNRS 6249, La Bouloie, F-25030 Besançon Cedex, France. Electronic address: lotfi.aleya@univ-fcomte.fr.
authors.forename: Lotfi
authors.initials: L
authors.lastname: Aleya
mesh_terms: D018533:Biomass; D004784:Environmental Monitoring; D008522:Mediterranean Sea; D008962:Models, Theoretical; D009584:Nitrogen / Q000032:analysis; D010100:Oxygen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D010839:Phytoplankton; D010933:Plankton; D012621:Seasons; D012623:Seawater / Q000737:chemistry* / Q000382:microbiology; D014416:Tunisia; D014867:Water / Q000032:analysis; D014876:Water Pollution / Q000032:analysis / Q000706:statistics & numerical data
chemical_list: D014867:Water; D010758:Phosphorus; D009584:Nitrogen; D010100:Oxygen
keywords: Coupled hydrodynamic biogeochemical model; Nutrient budget, water quality, lagoon; Water budget