Accession Number : ADA318378

Title :   Bioluminescence Source Emission Characterization.

Descriptive Note : Final technical rept. 1 Apr 92-30 Sep 95,

Corporate Author : SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA MARINE BIOLOGY RESEARCH DIV

Personal Author(s) : Latz, Michael I.

PDF Url : ADA318378

Report Date : 30 SEP 1995

Pagination or Media Count : 6

Abstract : A study of the hydrodynamics characterization of the excitation of bioluminescence was performed in collaboration with NRaD scientist Dr. James Rohr. Present research using fully developed pipe flow confirmed previous work using Couette flow that the excitation threshold for dinoflagellate bioluminescence occurred in laminar flow at a shear stress level greater than typical levels in the mixed layer. Maximum response was achieved at high laminar flow values, with no further increase for turbulent flows. A study of the spontaneous bioluminescence of the dinoflagellate Ceratocorys horrida revealed that this species exhibited circadian rhythms in both spontaneous flashing and glowing. Spontaneous light emission in dinoflagellates may be an important source of natural bioluminescence in the ocean. Several approaches tested the hypothesis that spontaneous flashing by dinoflagellates is caused by cell collisions. The results from experiments involving impaired swimming, direct observations of colliding cells, and surface to volume manipulations were not able to confirm the hypothesis. Unialgal red tide dinoflagellate diet significantly affected the total bioluminescence potential and flash intensity of two local species of heterotrophic dinoflagellates. Cannibalism was an important source of nutrition during periods of prey scarcity. Bioluminescence appears to be a sensitive indicator of energetic state in heterotrophic dinoflagellates.

Descriptors :   *LAMINAR FLOW, *PLANKTON, *BIOLUMINESCENCE, *DINOFLAGELLATA, EMISSION, SOURCES, VOLUME, HIGH RATE, CIRCADIAN RHYTHMS, LAYERS, CELLS, THRESHOLD EFFECTS, EXCITATION, INTENSITY, LIGHT, TURBULENT FLOW, SENSITIVITY, RESPONSE, SHEAR STRESSES, MIXING, FLOW, HYPOTHESES, OCEANS, ENERGETIC PROPERTIES, DIET, NUTRITION, INDICATORS, HYDRODYNAMICS, COLLISIONS, SURFACE TO AIR, SWIMMING, COUETTE FLOW, SCIENTISTS, PIPE FLOW, FLASHES.

Subject Categories : Biochemistry
      Microbiology
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE