Emergy-based indicators for evaluating ecosystem health: A case study of three benthic ecosystem networks influenced by coastal upwelling in northern Chile (SE Pacific coast).

It has been hypothesized that ecosystem health describes the state in which all processes operating within an ecosystem are functioning at a level of optimum efficiency to maximize system empower. In this study, systems analysis of networks and information flows is used within this definition of ecosystem health to assess the condition of the benthic ecosystems in three coastal bays in northern Chile. These highly productive ecosystems are characterized by the inflow of cold, nutrient-rich waters of low oxygen concentration derived from coastal upwelling of deep waters and the interruption of upwelling flow during El Niño events when warmer waters with higher oxygen and lower nutrient concentrations enter these coastal systems.