Skip to main content
Publications | Persons | Institutes | Projects
[ report an error in this record ]basket (0): add | show Print this page

Nutrient dynamics and phytoplankton development along an estuary-coastal zone continuum: A model study
Arndt, S.; Lacroix, G.; Gypens, N.; Regnier, P.; Lancelot, C. (2011). Nutrient dynamics and phytoplankton development along an estuary-coastal zone continuum: A model study. J. Mar. Syst. 84(3-4): 49-66. dx.doi.org/10.1016/j.jmarsys.2010.08.005
In: Journal of Marine Systems. Elsevier: Tokyo; Oxford; New York; Amsterdam. ISSN 0924-7963; e-ISSN 1879-1573, more
Peer reviewed article  

Available in  Authors 

Keywords
    Algal blooms
    Cycles > Chemical cycles > Geochemical cycle > Biogeochemical cycle > Nutrient cycles
    Phytoplankton
    ANE, Netherlands, Westerschelde [Marine Regions]
    Marine/Coastal
Author keywords
    Land-ocean continuum; Scheldt; Reactive-transport model; Nutrient cycling; Phytoplankton bloom; Estuarine filter

Authors  Top 

Abstract
    This study presents a first attempt to quantify the biogeochemical transformations and fluxes of carbon and nutrients along the entire mixing zone of the shallow, tidally-dominated estuary–coastal zone continuum of the Scheldt (Belgium/The Netherlands). A fully transient, two-dimensional, nested-grid hydrodynamic model of the continuum is coupled to the biogeochemical MIRO model for the coastal zone and the CONTRASTE model for the estuary. Transient model simulations are performed with a high spatial (80–750 m) and temporal (30 min) resolution over a period of one year (January–December 1995). The high temporal resolution allows including the short-term variability triggered by the tides, the freshwater discharge and the wind stress. System scale simulations provide time series of nutrient transformations and fluxes along the entire estuary–coastal zone continuum, as well as highly resolved nutrient inventories for the estuarine and the coastal zone sub-domains. Simulation results reveal that the balance between highly variable estuarine nutrient inputs and physical constrains set by the unsteady residual transport field exert an important control on the magnitude and succession of phytoplankton blooms and the ecosystem structure in the coastal zone. In addition, they suggest that the poorly surveyed estuarine–coastal zone interface plays a central role in the continuum. In this dynamic area, marked spatial concentration gradients develop and episodically lead to a reversal of material fluxes from the coast into the estuary. During distinct episodes of the productive period, euryhaline coastal diatoms intrude far upstream into the saline estuary. This intrusion reduces the estuarine nutrient concentrations and export fluxes, thereby reinforcing the nutrient limitation in the coastal area. As a consequence, the estuarine filter does not operate independently from the processes in the coastal zone. The dynamic interplay between the two ecosystems and the intense process rates operating at their transition, therefore, strongly supports our continuum approach.

All data in the Integrated Marine Information System (IMIS) is subject to the VLIZ privacy policy Top | Authors