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Journal of Applied Phycology

, Volume 6, Issue 3, pp 331–335 | Cite as

Turbulence in mass algal cultures and the role of light/dark fluctuations

  • Johan U. Grobbelaar
Article

Abstract

In mass algal cultures, some form of agitation is usually provided; among other effects, this moves the organisms though an optically dense profile and provides mixing. During this transport, medium frequency fluctuations in the light energy supply are perceived by the algae, which are of the order of 1 Hz and less. It has been suggested that turbulence with the resultant light/dark cycles of medium frequency enhances productivity. However, turbulence has two major influences in a well mixed system: it facilitates fluctuating light regimes and increases the transfer rates between the growth medium and the cultured organism. An estimation of productivity as oxygen liberation was measured under laminar and turbulent flow rates, and varying light/dark ratios. Increased turbulence, which increased exchange rates of nutrients and metabolites between the cells and their growth medium, together with increased light/dark frequencies, increased productivity and photosynthetic efficiency.

Key words

turbulence photosynthesis Chlorella light/dark cycles mass transfer rates 

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References

  1. Allen MM (1968) Simple conditions for growth of unicellular blue-green algae on plates. J. Phycol. 4: 1–3.Google Scholar
  2. Cullen JJ, Lewis MR (1988) The kinetics of algal photoadaptation in the context of vertical mixing. J. Plankton Res. 10: 1039–1063.Google Scholar
  3. Dera J (1970) On two layers of different light conditions in the euphotic zone of the sea. Acta Geophys. Pol. 18: 287–294.Google Scholar
  4. Doty MS, Oguri M (1957) Evidence for a photosynthetic daily periodicity. Limnol. Oceanogr. 2: 37–40.Google Scholar
  5. Falkowski PG, Wirick CD (1981) A simulation model of the effects of vertical mixing on primary productivity. Mar. Biol. 45: 289–295.Google Scholar
  6. Fisher HB, List EJ, Koh RCY, Imberger J, Brooks NH (1979) Mixing in inland and coastal waters. Academic Press, New York, London, 483 pp.Google Scholar
  7. Friedrickson AG, Tsuchiya HM (1970) Utilization of the effects of intermittent illumination on photosynthetic microorganisms. In: Prediction and measurement of photosynthetic productivity. Wageningen Centre for Agricultural Publishing and Documentation: 519–541Google Scholar
  8. Grobbelaar JU (1989) Do light/dark cycles of medium frequency enhance phytoplankton productivity? J. appl. Phycol. 1: 333–340.Google Scholar
  9. Grobbelaar JU (1991) The influence of light/dark cycles in mixed algal cultures on their productivity. Bioresource Tech. 38: 189–194.Google Scholar
  10. Grobbelaar JU, Kroon BMA, B.-Wiersma T, Mur LR (1992) Influence of medium frequency light/dark cycles of equal duration on the photosynthesis and respiration ofChlorella pyrenoidosa. Hydrobiologia 238: 53–62.Google Scholar
  11. Kok B (1953) Experiments on photosynthesis byChlorella in flashing light. In Burlew J ded.), Algal culture from laboratory to pilot plant. Carnegie Institution of Washington, Washington, D.C.: 63–158.Google Scholar
  12. Jewson DH, Wood RB (1975) Some effects on integral photosynthesis of artificial circulation of phytoplankton through light gradients. Verh. int. Verein Limnol. 19: 1037–1044.Google Scholar
  13. Laws EA, Terry KL, Wickman J, Challup MS (1983) A simple algal production system designed to utilize the flashing light effect. Biotechnol. Bioengng 25: 2319–2335.Google Scholar
  14. Legendre L, Rochet M, Demers S (1986) Sea-ice microalgae to test the hypothesis of photosynthetic adaption to high frequency light fluctuations. J. exp. mar. Biol. Ecol. 97: 321–326.Google Scholar
  15. Marra, J (1980) Vertical mixing and primary production. In P.G. Falkowski ded.), Primary productivity in the sea. Plenum Press, New York: 121–137.Google Scholar
  16. Merchuk JC (1988) Shear effects on suspended cells. Advances in Biochem. Eng. Biotech. 44: 65–95.Google Scholar
  17. Richmond A, Becker EW (1986) Technological aspects of mass cultivation — A general outline. In Richmond A ded.), Handbook of Microalgal Mass Culture. CRC Press, Inc., Boca Raton: 245–263.Google Scholar
  18. Richmond A, Vonshak A (1978)Spirulina culture in Israel. Arch. Hydrobiol. Beih., Ergebn. Limnol. 11: 274–280.Google Scholar
  19. Sartory DP, Grobbelaar JU (1984) Extraction of chlorophylla from freshwater phytoplankton for spectrophotometric analysis. Hydrobiologia 114: 177–187.Google Scholar
  20. Sorokin C (1957) Changes in photosynthetic activity in the course of cell development inChlorella. Physiol. Pl. 10: 659–666.Google Scholar
  21. Terry KL (1986) Photosynthesis in modulated light: Quantitative dependence of photosynthetic enhancement on flashing rate. Biotechnol. Bioengng 28: 988–995.Google Scholar

Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • Johan U. Grobbelaar
    • 1
  1. 1.Department of Botany and GeneticsUniversity of the OFSBloemfonteinSouth Africa

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