Articles | Volume 12, issue 3
Nonlin. Processes Geophys., 12, 337–343, 2005
https://doi.org/10.5194/npg-12-337-2005
Nonlin. Processes Geophys., 12, 337–343, 2005
https://doi.org/10.5194/npg-12-337-2005

  21 Feb 2005

21 Feb 2005

Dinoflagellate bioluminescence in response to mechanical stimuli in water flows

A. S. Cussatlegras1 and P. Le Gal2 A. S. Cussatlegras and P. Le Gal
  • 1DIMAR, UMR 6540 CNRS-Universit´e de la Méditerranée, Centre d’Océanologie de Marseille, Parc Scientifique et technologique de Luminy, Case 901, 13288 Marseille cedex 9, France
  • 2IRPHE, UMR 6594 CNRS-Universités d’Aix-Marseille I & II, 49 rue F. Joliot-curie, BP 146, 13384 Marseille cedex 13, France

Abstract. Bioluminescence of plankton organisms induced by water movements has long been observed and is still under investigations because of its great complexity. In particular, the exact mechanism occurring at the level of the cell has not been yet fully understood. This work is devoted to the study of the bioluminescence of the dinoflagellates plankton species Pyrocystis noctiluca in response to mechanical stimuli generated by water flows. Several experiments were performed with different types of flows in a Couette shearing apparatus. All of them converge to the conclusion that stationary homogeneous laminar shear does not trigger massive bioluminescence, but that acceleration and shear are both necessary to stimulate together an intense bioluminescence response. The distribution of the experimental bioluminescence thresholds is finally calculated from the light emission response for the Pyrocystis noctiluca species.