M. Gregoire et al., RECONNAISSANCE OF THE MAIN BLACK-SEA ECOHYDRODYNAMICS BY MEANS OF A 3D INTERDISCIPLINARY MODEL, Journal of marine systems, 16(1-2), 1998, pp. 85-105
A 3D interdisciplinary model has been used to test the sensitivity of
the Black Sea's ecosystem to physical processes. The hydrodynamical mo
del of the general circulation has been built up, using the GHER primi
tive equation model. A model with 15 km horizontal resolution and 25 v
ertical levels is used to compute the typical seasonal cycle. The mode
l is forced by climatological monthly mean fields of temperature, sali
nity and wind stress at the air-sea interface; the river discharges of
the Danube, Dnestr and Dnepr are taken into account. An ecosystem mod
el at basin scale is then defined by a nitrogen cycle considering seve
ral phytoplankton and zooplankton sizes and including the microbial lo
op. The ecosystem model is embedded on-line into the 3D hydrodynamical
model with a superimposed cycle for the light intensity. This model m
ust be regarded rather as a first tool for testing the coupling of hyd
rodynamic and ecosystem submodels, while acquiring some preparatory as
sessment of the effect of physical processes on the ecodynamics. The r
esults display a highly three-dimensional aspect with important horizo
ntal and vertical variations, obviously imparted to the system by the
physical processes (horizontal and vertical advection, vertical mixing
and diffusion, upwelling...) associated with light limitation at dept
h and sinking of dead organisms. In this paper, the results are descri
bed emphasizing the effects of the hydrodynamic constraints on the spa
ce-time distribution of the primary and secondary production. (C) 1998
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