title: Variability of primary and bacterial production in a coral reef lagoon (New Caledonia).
abstract: We assessed the temporal variability of nutrients, phytoplankton and bacterioplankton at two sites of different trophic status in New Caledonia's South-West lagoon, a tropical coastal ecosystem. During stable meteorological conditions, Chl.a, bacterial production and nutrient concentrations experience weak but consistent daily variation. Short-term (1-2 week interval) fluctuations of planktonic variables are in the same range as annual variations at both sites. A part of these short term variations is linked to local meteorological events (wind in the main channel, precipitation at the coastal station). Although annual variations are weak compared to short term variations, phytoplankton and bacterioplankton production show consistent temporal patterns, with maxima in December-January and April-May and minima in August. Annual bacterial production represents 21% and 34% of particulate primary production at the oligotrophic and mesotrophic sites, respectively. Mineral nutrient availability indicates that nitrogen is probably the primary limiting factor of phytoplankton throughout the year.
authors.affiliation: UR 103, CAMELIA, UMR 5119 ECOLAG, Université Montpellier II, Case 093, 34095 Montpellier, France. jean-pascal.torreton@ird.fr
authors.forename: Jean-Pascal
authors.initials: JP
authors.lastname: Torréton
authors.forename: Emma
authors.initials: E
authors.lastname: Rochelle-Newall
authors.forename: Olivier
authors.initials: O
authors.lastname: Pringault
authors.forename: Séverine
authors.initials: S
authors.lastname: Jacquet
authors.forename: Vincent
authors.initials: V
authors.lastname: Faure
authors.forename: Enora
authors.initials: E
authors.lastname: Briand
mesh_terms: D018407:Bacterial Physiological Phenomena; D018533:Biomass; D002734:Chlorophyll / Q000032:analysis; D000077194:Chlorophyll A; D017753:Ecosystem; D004784:Environmental Monitoring; D057446:Hydrodynamics; D009584:Nitrogen / Q000032:analysis / Q000378:metabolism; D010839:Phytoplankton; D010933:Plankton / Q000382:microbiology*; D011891:Rain; D012621:Seasons; D012623:Seawater / Q000737:chemistry / Q000382:microbiology; D013997:Time Factors; D014871:Water Microbiology; D014919:Wind
chemical_list: D002734:Chlorophyll; D009584:Nitrogen; D000077194:Chlorophyll A