A tentative classification of coastal marine ecosystems based on dominant processes of nutrient supply

High rates of marine primary production, as well as most world fishery production, are confined to coastal regions. There are three categories of nutrient enrichment processes: (1) coastal upwelling, (2) tidal mixing, and (3) land-based runoff and major river outflow. These are depicted on a single map as a basis for identification of groups of regional marine ecosystems that may have analogous aspects with respect to basic modes of enrichment. These groupings may provide a rational framework for comparative ecological studies. The concept of the marine catchment basin (MCB) is stressed as representing the logical unit for management of anthropogenic effects on any marine ecosystem that is substantially affected by terrestrial runoff.