To assess the status of the natural system, it is critical to understand the interactions among the physical, chemical, and biological components of the Everglades landscape. The key is to simplify these interactions down to their most fundamental components, especially where supporting data are sparse.
This (clickable using a web browser) General Ecosystem Conceptual Model summarizes the basics of these interactions among multiple variables in the landscape. This conceptual model is at the heart of the dynamic equations that comprise the Everglades Landscape Model, and has been part of a framework of research hypotheses. We have devoted a very large part of ELM efforts on developing the simplest set of fundamental, interacting equations that we believe effectively capture the essense of the important ecosystem dynamics.
Note: because the Everglades is such a tightly integrated functional system (as seen in the relationships in this Conceptual Model), it can be somewhat misleading to attempt to "measure" the performance of the system through one or two attributes such as water depth or water column nutrient concentration. The multiple Performance Measures that are being used for CERP and other restoration projects can best be understood and interpreted from a well-integrated, systems ecology perspective.