EUROPEAN LAGOONS
2D finite element ecological model for the Curonian lagoon
Petras Zemlys Æ Ali Ertu
¨
rk Æ Artu
¯
ras Razinkovas
Ó Springer Science+Business Media B.V. 2008
Abstract The results of application of 2D finite
element model SHYFEM to the Curonian lagoon
(Baltic Sea) are considered. SHYFEM consist of a
physical processes module and an eutrophication
module EUTRO adapted for the SHYFEM code from
well known modelling system WASP. The SHY-
FEM/EUTRO model calibration results were
compared with the performance of various biogeo-
chemical models analysed in other studies (153
studies published from 1990 to 2002). The perfor-
mance of all corresponding state variables—
dissolved oxygen, NO
3
,NH
4
,PO
4
, phyto- and
zooplankton—was slightly lower than median model
performance which could be considered satisfactory
given the initial state of model formulation and
calibration. Model underestimates phytoplankton
autumn blooms, especially for the southern part of
the lagoon, where fine sediments dominate and water
residence time is high. It can be concluded that, in
order to increase model performance, the eutrophi-
cation module should be improved to account for the
dominance of different phytoplankton groups as well
as for the exchanges between the sediments and the
water column. The amount and quality of the data
available for the model setup and calibration are
unsatisfactory and should be improved for the
development of the next enhanced model version.
Keywords Coastal lagoons Á Curonian lagoon Á
Eutrophication Á Ecological modelling Á
SHYFEM
Introduction
The Curonian lagoon (Baltic Sea) is a shallow, large
estuarine lagoon with complex interactions between
biotic and abiotic components. Effective management
of such a complex systems cannot be solely based on
observations and measurements. It requires also more
sophisticated tools, such as mathematical models, that
provide managers with a more holistic view of the
physical, chemical and biological processes and their
interactions and are suitable as decision support tools.
Modelling of large heterogenic ecosystems
requires the coupling of biochemical and physical
processes. During the recent years, several hydrody-
namic models were applied to the Curonian Lagoon
(Davulien
_
e et al., 2002; Raudsepp & Ko
˜
uts, 2002;
Guest editors: A. Razinkovas, Z. R. Gasiu
¯
nait
_
e, J. M. Zaldivar
& P. Viaroli
European Lagoons and their Watersheds: Function and
Biodiversity
P. Zemlys (&) Á A. Razinkovas
Coastal Research and Planning Institute,
Klaip
_
eda University, Klaip
_
eda, Lithuania
e-mail: petras.zemlys@ku.lt
A. Ertu
¨
rk
Faculty of Civil Engineering, Department of
Environmental Engineering, Istanbul Technical
University, 34469 Maslak, Istanbul, Turkey
123
Hydrobiologia (2008) 611:167–179
DOI 10.1007/s10750-008-9452-7