The Application of Conceptual Models to Ecosystem Restoration

In its report to the Chief of Engineers, the U.S. Army Corps of Engineers (USACE) Environmental Advisory Board (EAB) recommended that (USACE, EAB 2006): The Corps should encourage the explicit use of conceptual models to guide ecosystem restoration planning and implementation. Conceptual models should be required as a first step in the planning process, as they provide a key link between early planning (e.g., an effective statement of problem, need, opportunity, and constraint) and later evaluation and implementation. Conceptual models are descriptions of the general functional relationships among essential components of an ecosystem. They tell the story of how the system works and, in the case of ecosystem restoration, how restoration actions aim to alter those processes or attributes for the betterment of the system. As such, conceptual models can provide the Ecosystem Restoration Team with: a synthesis of the current understanding of how a system works help in understanding and diagnosing the underlying problem a basis for isolating cause and effect and simplifying complex systems a common framework or mental picture from which to develop alternatives a tool for making qualitative predictions of ecosystem response a way to flag potential thresholds, from which system responses may accelerate or follow potentially unexpected or divergent paths a means by which to outline further restoration, R&D, and computational efforts a supplement to numerical models for assessing project benefits and impacts a means of identifying appropriate monitoring indicators and metrics, and a basis for implementing adaptive management strategies Most professionals rely heavily upon conceptual models, but few explicitly formulate and express the models such that they provide broad utility for ecosystem restoration.