Spatial Structure of Pelagic Ecosystem Processes in the Global Ocean

We propose an operational definition of spatial structure in the oceanic ecosystem; it is equivalent to the large-scale, horizontal distribution of the dominant ecophysiological rate parameters for the questions of interest. In an important, particular case, the relevant rate parameters are those that characterize autotrophic production. In the ocean, these parameters are believed to be distributed in a manner that is not smoothly continuous. Rather, they seem to have a piecewise continuous distribution. This leads to a requirement to partition the ocean into a suite of provinces where the boundaries between the provinces mark the locations of abrupt changes in the magnitudes of the rate parameters. The area covered by a particular province represents an area of common physical forcing, insofar as the forcing is relevant to autotrophic production. The boundaries are taken to be elastic rather than fixed, such that they can respond to variations in forcing. At any given time, the boundaries can be located with the aid of remotely sensed imagery, especially ocean-color imagery. Received 7 January 1999; accepted 2 June 1999.