How Viscoelastic Properties of Colloids, Transparent Exopolymeric Particles and Marine Organic Aggregates, Modify Turbulence and Plankton Biodynamics in the Sea

  • Tim Wyatt
  • I. Jenkinson
  • A. Malej

Abstract

Measurements of viscoelasticity, have already been made using Couette geometry, in the sea itself (See Jenkinson et al, this volume), in ≈1m3 mesocosms, and in phytoplankton suspensions and cultures. These measurements show that the sea is generally a hierarchically lumpy gel, with excess viscous moduli (i. e. in excess of that due to the aqueous phase) and elastic moduli strongly correlated with the quantity of phytoplankton present (measured as chlorophyll content). Formation of these gels starts mainly from colloidal (sub-micrometer) molecules (Gentien, 1995), much of which is probably secreted by phytoplankton. Because they are sticky, they flocculate in deforming water to form Transparent Exopolymeric Particles (TEP - 1 to ≈100 μm) (Mari & Kiørboe, 1996). These TEP are fractal organic aggregates that then flocculate further by sticking to each other and sometimes also to fibres and other biological debris (Mari & Kiørboe, 1996). They are also colonised by bacteria. By these means they can form visible gels (Chin et al, 1998), organic aggregates of size several ≈m to mm (Kiørboe & Hansen, 1993; Worm & Søndergaard, 1998), or even metres in the northern Adriatic (Malej & Harris, 1993; Malej et al, this volume).

Keywords

Chlorophyll Phytoplankton Flocculation 

References

  1. Chin W-C, Orellana MV, Verdugo, P. (1998) Nature 391:568–571ADSCrossRefGoogle Scholar
  2. Gentien P, Lunven M, Lehaître M, Duvent JL (1995) Deep-Sea Res. I 42:1297–1312CrossRefGoogle Scholar
  3. Jenkinson IR, Biddanda BA, Turley CM, Abreu PC, Riebesell U, Smetacek VS (1991) Oceanologia Acta, Sp Vol No 11:101–107Google Scholar
  4. Jenkinson IR, Wyatt T (1992) J. Plankton Res. 14:1697–1721CrossRefGoogle Scholar
  5. Kiørboe T, Hansen JLS (1993) J. Plankton Res. 15:993–1018CrossRefGoogle Scholar
  6. Malej A, Harris RP (1993) Mar. Ecol. Prog. Ser. 96:33–42CrossRefGoogle Scholar
  7. Man X, Kiørboe T (1996) J. Plankton Res. 18: 969–986CrossRefGoogle Scholar
  8. Sanford LP (1997) Mar. Ecol. Prog. Ser. 161: 265–293CrossRefGoogle Scholar
  9. Worm J, Søndergaard M (1998) J. Plankton Res. 20:179–186CrossRefGoogle Scholar
  10. Wyatt T, Jenkinson IR (1997) J. Plankton Res. 19:551–575CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Tim Wyatt
    • 1
  • I. Jenkinson
    • 2
  • A. Malej
    • 3
  1. 1.Instituto de Investigaciones MarinasCSICVigoSpain
  2. 2.ACROLavergneFrance
  3. 3.NIBMarine Biology station PiranPiranSlovenia

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