The Use of Optimization Techniques to Model Marine Ecosystem Dynamics at the JGOFS Station at 47 degrees N 20 degrees W [and Discussion]

A seven-compartment model of the mixed layer ecosystem was used to fit a time series of observations derived from data obtained during the 1989 JGOFS North Atlantic Bloom Experiment. A nonlinear optimization technique was used to obtain the best fit to the combined observation set. 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 number of other independent data sets, but overestimated bacterial production. Further development is necessary to create a model capable of reproducing all the important features of the nitrogen flows within the mixed layer.

[1]  M. Fasham.  Variations in the seasonal cycle of biological production in subarctic oceans: A model sensitivity analysis , 1995 .

[2]  J. Wroblewski,et al.  A model of phytoplankton plume formation during variable Oregon upwelling , 1977 .

[3]  B. Frost,et al.  Grazing control of phytoplankton stock in the open subarctic Pacific Ocean: a model assessing the role of mesozooplankton, particularly the large calanoid copepods Neocalanus spp. , 1987 .

[4]  H. Ducklow,et al.  Plankton succession and carbon cycling at 47°N 20°W during the JGOFS North Atlantic Bloom Experiment , 1993 .

[5]  S. J. Tanner,et al.  Iron, primary production and carbon-nitrogen flux studies during the JGOFS North Atlantic bloom experiment , 1993 .

[6]  S. Poulet.  Factors controlling utilization of non-algal diets by particle-grazing copepods - a review , 1983 .

[7]  J. C. Goldman,et al.  Regulation of gross growth efficiency and ammonium regeneration in bacteria by substrate C: N ratio1 , 1987 .

[8]  H. Ducklow,et al.  Stocks and dynamics of bacterioplankton carbon during the spring bloom in the eastern North Atlantic Ocean , 1993 .

[9]  S. Levitus.  Climatological Atlas of the World Ocean , 1982 .

[10]  J. Marra,et al.  Initiation of the spring bloom in the northeast Atlantic (47°N, 20°W): a numerical simulation , 1993 .

[11]  Thomas D. Brock,et al.  Calculating solar radiation for ecological studies , 1981 .

[12]  Allan R. Robinson,et al.  Coupled physical and biological modeling of the spring bloom in the North Atlantic (I): model formulation and one dimensional bloom processes , 1995 .

[13]  A. H. Taylor,et al.  Seasonal succession in the pelagic ecosystem of the North Atlantic and the utilization of nitrogen , 1993 .

[14]  Frank E. Hoge,et al.  Mesoscale and upper ocean variabilities during the 1989 JGOFS bloom study , 1993 .

[15]  B. Frost.  A modelling study of processes regulating plankton standing stock and production in the open Subarctic Pacific Ocean , 1993 .

[16]  Wolfgang H Berger,et al.  Global maps of ocean productivity. , 1989 .

[17]  H. Ducklow,et al.  A nitrogen-based model of plankton dynamics in the oceanic mixed layer , 1990 .

[18]  M. Sieracki,et al.  Plankton community response to sequential silicate and nitrate depletion during the 1989 North Atlantic spring bloom , 1993 .

[19]  H. Ducklow,et al.  Introduction to the JGOFS North Atlantic bloom experiment , 1993 .

[20]  M. Fasham,et al.  Modelling the Marine Biota , 1993 .

[21]  John H. Steele,et al.  The Significance of Interannual Variability , 1993 .

[22]  Q. Dortch,et al.  The interaction between ammonium and nitrate uptake in phytoplankton , 1990 .

[23]  J. Steele,et al.  The role of predation in plankton models , 1992 .

[24]  P. Burkill,et al.  Microzooplankton and their herbivorous activity in the northeastern Atlantic Ocean , 1993 .

[25]  J. R. Nelson,et al.  Grazing, growth and mortality of microzooplankton during the 1989 North Atlantic spring bloom at 47°N, 18°W , 1993 .

[26]  Taro Takahashi,et al.  Primary production at 47°N and 20°W in the North Atlantic Ocean: a comparison between the 14C incubation method and the mixed layer carbon budget , 1993 .