THE USE OF OPTIMIZATION TECHNIQUES TO MODEL MARINE ECOSYSTEM DYNAMICSAT THE JGOFS STATION AT 47-DEGREES-N 20-DEGREES-W

A seven-compartment model of the mixed layer ecosystem was used to fit a time series of observations derived from data obtained during the 1 989 JGOFS North Atlantic Bloom Experiment. A nonlinear optimization te chnique was used to obtain the best fit to the combined observation se t. It was discovered that a solution which gave a good fit to primary production gave a bad fit to zooplankton and vice versa. The solution which fitted primary production also showed good agreement with a numb er of other independent data sets, but overestimated bacterial product ion. Further development is necessary to create a model capable of rep roducing all the important features of the nitrogen flows within the m ixed layer.