, Volume 311, Issue 1–3, pp 215–224

Estimating estuarine residence times in the Westerschelde (The Netherlands) using a box model with fixed dispersion coefficients

  • Karline Soetaert
  • Peter M. J. Herman


The residence time of the water masses in the Westerschelde estuary was determined using a simple compartment-model that simulates the advective-diffusive transport of a conservative dissolved substance (chlorinity). The residence time of a water parcel in the upstream part of the estuary (i.e. the time needed for this water parcel to leave the estuary) varied from about 50 days in winter to about 70 days in summer. The most seaward compartment had residence times of about 10-15 days.

Dispersive coefficients that are fixed in time were able to reproduce the observed salinity distributions very well in the Westerschelde. They were obtained by calibration on observed chlorinities. It is argued that the apparent relationship of dispersive coefficients with freshwater flow, which is observed in certain studies, could (partly) reflect the deviation from steady state conditions which are required assumptions to calculate these dispersive coefficients directly from salinity profiles.

Key words

residence times Westerschelde estuary 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. de Hoop, B. J., P M. J. Herman, H. Scholten & K. Soetaert, 1993. SENECA 2.0. A Simulation ENvironment for ECological Application. Manual.Google Scholar
  2. Heip, C., 1988. Biota and abiotic environment in the Westerschelde estuary. Hydrobiol. Bull. 22: 31–34.Google Scholar
  3. Helder, W. & P. Ruardij, 1982. A one-dimensional mixing and flushing model of the Ems-Dollard estuary: calculation of time scales at different river discharges. Net. J. Sea Res. 15: 293–312.Google Scholar
  4. Klepper, O., H. Scholten & J. P. G. Van de Kamer, 1991. Prediction uncertainty in an ecological model of the Oosterscheldt estuary. J. forecasting 10: 191–209.Google Scholar
  5. Loder, T. C. & R. P. Reichard, 1981. The dynamics of conservative mixing in estuaries. Estuaries 41: 64–69.Google Scholar
  6. Miller, R. L. & B. F. McPherson, 1991. Estimating estuarine flushing and residence times in Charlotte Harbor, Florida, via salt balance in a box model. Limnol. Oceanogr. 36: 602–612.Google Scholar
  7. O'Kane, J. P., 1980. Estuarine water-quality manaqement. Pitman, Boston.Google Scholar
  8. Radford, P. J., 1978. Some aspects of an estuarine ecosystem model — GEMBASE. In Jorgensen (ed.), State of the art in ecological modelling, Pergamon Press, Oxford, 301–322.Google Scholar
  9. Ruardij, P. & J. W. Baretta, 1988. The construction of the transport model. In Baretta & Ruardij (eds), Tidal flat estuaries. Simulation and analysis of the Ems estuary. Springer-Verlag, Berlin: 65–76.Google Scholar
  10. SAWES, 1992. Waterkwaliteitsmodel Westerschelde. WL-rapport T257.Google Scholar
  11. Soetaert, K. & P. M. J. Herman, 1995a. Nitrogen dynamics in the Westerschelde estuary (SW Netherlands) estimated by means of the ecosystem model MOSES. Hydrobiologia 311 (Dev. Hydrobiol. 110): 225–246.Google Scholar
  12. Soetaert, K. & P. M. J. Herman, 1995b. Carbon flows in the Westerschelde estuary (The Netherlands) evaluated by means of an ecosystem model (MOSES). Hydrobiologia 311 (Dev. Hydrobiol. 110): 247–266.Google Scholar
  13. Takeoka, H., 1984. Fundamental concepts of exchange and transport time scales in a coastal sea. Cont. Shelf Res. 3: 311–326.Google Scholar
  14. Thomann, R. V. & J. A. Mueller, 1987. Principles of surface water quality modelling and control. New York, Harper & Row.Google Scholar
  15. Uncles, R. J. & P. J. Radford, 1980. Seasonal and spring-neap tidal dependence of axial dispersion coefficients in the Severn — a wide, vertically mixed estuary. J. Fluid Mech. 98: 703–726.Google Scholar
  16. Van Eck, G. Th. M. & N. M. de Rooij, 1990. Development of a water quality and bio-accumulation model for the Scheldt estuary. In W. Michaelis (ed.), Coastal and Estuarine Studies. Springer Verlag. Berlin, Heidelberg, etc. 95–104.Google Scholar
  17. Wollast, R., 1983. Interactions in estuaries and coastal waters. In Bolin, B. & R. B. Cook (eds), The major biogeochemial cycles and their interactions. Scope.Google Scholar
  18. Zimmerman, J. T. F., 1976. Mixing and flushing of tidal embayments in the western Dutch Wadden Sea. Part I.: distribution of salinity and calculation of characteristic mixing time scales. Neth. J. Sea Res. 10: 149–191.Google Scholar

Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • Karline Soetaert
    • 1
  • Peter M. J. Herman
    • 1
  1. 1.Centre for Estuarine and Coastal ecologyNetherlands Institute of EcologyYersekeThe Netherlands

Personalised recommendations