Colloquium 1996


Main page



28th International Liège Colloquium on Ocean Hydrodynamics

Modelling hydrodynamically dominated marine ecosystems

Liège, May 6-10 1996

General introduction

Modelling ecosystems in a sustainable development perspective is a truly interdisciplinary challenge.
Biogeochemical cycles cannot be considered independently of the hydrodynamic constraints exerted on them.
Hydrodynamic processes the time scales of which correspond to the time scales of biological populations, capture these populations in their physical spatial structures (the so-called "ecohydrodynamic adjustment") and the frequency and persistence of the latter command the speed of the exchanges between the marine biosphere, the ocean reservoirs and the atmosphere.
It is difficult to see how a simple model could be used to describe ecosystems and biogeochemical cycles. On the one hand, geochemical and ecological processes are strongly correlated with physical processes by the resonant interactions and subsequent scale matching of the ecohydrodynamic adjustment; in addition, they live on nutrient supplies which are partly regenerated in the water column - hence subject to the caprices of local hydrodynamics -, partly imported into the system through the boundaries (bottom-sediments, coasts, air-sea interface,...) with a spatial variability which, inevitably, is imprinted on the system's kinetics. On the other hand, the complexity and diversity of ecological and geochemical interactions webs leaves little hope for the development of realistic management models including too simpliste biology and geochemistry.
Yet, there are limitations, -if not on computing power and computing time in a foreseeable future-, on the volume of computer products, the -technical and human- ways and means of exploiting them for the advancement of our basic scientific understanding or the development of rational management schemes, in any reasonable time.
A trade-off must be found between physical and biogeochemical complexity of the models.
When the hydrodynamic constraints play a cogent part (as in fronts, upwellings...), there is a tendency among the hydrodynamicists to investigate the physics in details and try to get away with a very simple representation of the biology.
The purpose of the Colloquium is to provide a forum for discussing the success and shortcomings of these hydrodynamics-dominated models, inviting biologists and geochemists to report their own progresses (approaching the system from the other side, so to say) and identify the bases for the development of models of optimal complexity.

International Scientific Organizing Committee

A. Berger, Institut d'Astronomie et de Géophysique, University of Louvain, Belgium.

M. Fasham, James Rennel Centre for Ocean Circulation, Southampton, U.K.

E.E. Hofmann, Centre for Coastal Physical Oceanography, Old Dominion University, USA.

S.E. Jorgensen, University of Copenhagen, Denmark.

T. Komatsu, Ocean Research Institute, University of Tokyo, Japan.

L. Legendre, Université Laval, Québec, Canada.

C. Moloney, University of Cape Town, South Africa.

J.C.J. Nihoul (Chairman), GHER, University of Liège, Belgium.

G. Radach, Institüt fur Meereskunde, Universität Hamburg, Germany.

A. Robinson, Division of Applied Science, Harvard University, USA (Chairman of the Globec Modelling Group).

B. Rotschild, Chesapeak Biological Laboratory, USA.

J.O. Strømberg, Kristineberg Marine Laboratory Biological Station, Fiskebackskil, Sweden.

J.J. Walsh, Departement of Marine Science, University of Florida, USA.

Local Organizing Committee

E. Delhez

S. Djenidi (Chairman)

Ch. Winand (Secretary)

Address :

GHER - Modelenvironment
University of Liège
Sart Tilman, B5
B-4000 Liège, Belgium

Phone : +32 41 66 33 50
Fax : +32 41 66 23 55
e-mail :


The members of the Organizing Committees wish to express their gratitude to the :

  • Commission of the European Union
  • Fonds National de la Recherche Scientifique (FNRS, Belgium)
  • Institut de Recherche Marines et d'interactions Air-mer (IRMA, Belgium)
  • Intergovernmental Oceanographic Commission of the UNESCO (IOC)
  • International Association for the Physical Sciences of the Ocean (IAPSO)
  • Ministère de l'Enseignement supérieur et de la Recherche scientifique (Belgium)
  • National Science Foundation (NSF, USA)
  • Office of Naval Research (ONR, USA)
  • Scientific Council on Oceanic Research (SCOR, XSU)
  • Province de Liège
  • Université de Liège

Final program



[Colloquium 2004] [Colloquium 2003] [Colloquium 2002] [Colloquium 2001] [Colloquium 2000] [Colloquium 1999] [Colloquium 1998] [Colloquium1997] [Colloquium 1996]


[Main page]

 Last modified 09/26/01