title: Heterogeneous distribution of plankton within the mixed layer and its implications for bloom formation in tropical seas.
abstract: Intensive sampling at the coastal waters of the central Red Sea during a period of thermal stratification, prior to the main seasonal bloom during winter, showed that vertical patches of prokaryotes and microplankton developed and persisted for several days within the apparently density uniform upper layer. These vertical structures were most likely the result of in situ growth and mortality (e.g., grazing) rather than physical or behavioural aggregation. Simulating a mixing event by adding nutrient-rich deep water abruptly triggered dense phytoplankton blooms in the nutrient-poor environment of the upper layer. These findings suggest that vertical structures within the mixed layer provide critical seeding stocks that can rapidly exploit nutrient influx during mixing, leading to winter bloom formation.
authors.affiliation: Institut de Ciències del Mar, CSIC, Ps. Marítim de la Barceloneta, 37-49, 08003 Barcelona, Catalunya, Spain.
authors.forename: Albert
authors.initials: A
authors.lastname: Calbet
authors.affiliation: National Institute of Aquatic Resources (DTU Aqua), Section for Marine Ecology and Oceanography, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark.
authors.forename: Mette Dalgaard
authors.initials: MD
authors.lastname: Agersted
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia.|Department of Biosciences, University of Oslo, Postboks 1066 Blindern, 0316 Oslo, Norway.
authors.forename: Stein
authors.initials: S
authors.lastname: Kaartvedt
authors.affiliation: National Institute of Aquatic Resources (DTU Aqua), Section for Marine Ecology and Oceanography, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark.
authors.forename: Malene
authors.initials: M
authors.lastname: Møhl
authors.affiliation: Department of Bioscience, Aarhus University, Frederiksborgvej 399, PO Box 358 DK-4000 Roskilde, Denmark.
authors.forename: Eva Friis
authors.initials: EF
authors.lastname: Møller
authors.affiliation: National Institute of Aquatic Resources (DTU Aqua), Section for Marine Ecology and Oceanography, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Enghoff-Poulsen
authors.affiliation: Marin Microbiology, University of Bergen, Thormøhlensgate 53 B, 5006 Bergen, Norway.
authors.forename: Maria Lund
authors.initials: ML
authors.lastname: Paulsen
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Solberg
authors.affiliation: Department of Biosciences &Centre for Sustainable Aquatic Research (CSAR), Swansea University, SA2 8PP, United Kingdom.
authors.forename: Kam W
authors.initials: KW
authors.lastname: Tang
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Red Sea Research Center, Thuwal, Saudi Arabia.|Uni Research Environment, P. box 7810, 5020 Bergen, Norway.
authors.forename: Kajsa
authors.initials: K
authors.lastname: Tönnesson
authors.affiliation: Remote Sensing Group. Plymouth Marine Laboratory, PL1 3DH, UK.
authors.forename: Dionysios E
authors.initials: DE
authors.lastname: Raitsos
authors.affiliation: National Institute of Aquatic Resources (DTU Aqua), Section for Marine Ecology and Oceanography, Technical University of Denmark, Kavalergården 6, DK-2920 Charlottenlund, Denmark.
authors.forename: Torkel Gissel
authors.initials: TG
authors.lastname: Nielsen
mesh_terms: D005068:Eutrophication / Q000502:physiology*; D019156:Indian Ocean; D010839:Phytoplankton / Q000254:growth & development*; D012621:Seasons; D012623:Seawater / Q000737:chemistry; D014887:Weather