Eutrophication conceptual model

Figure 15.10 Conceptual model of eutrophication based on the concepts of (1) filter attributes, (2) nutrient enhancement as one of many stressors, (3) complex linkages between stressors, (4) impact of coastal change on global scale, and (5) application of broader concepts of eutrophication on management issues. (Modified from Cloern, 2001.)...

Cloern, J.E. (2001) Our evolving conceptual model of the coastal eutrophication problem. Mar. Ecol. Prog. Ser. 210, 223-253. 

In addition to the conceptual model which isolates the major interacting systems, a further idealization is required which sets the lower and upper limits of the temporal and spatial scales being considered. Within the context of the problem of eutrophication and its control, the seasonal distribution of the phytoplankton is of major importance, so that the lower limit of the temporal scale is on the order of days. The spatial scale is set by the hydrodynamics of the water body being considered. For example, in a tidal estuary, the spatial scale is on the order of miles whereas in a small lake it is likely a good deal smaller. The upper limits for the temporal and spatial extent of the model are dictated primarily by practical considerations such as the length of time for which adequate information is available and the size of the computer being used for the calculations. 

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