Assured Mobility Simulator

Abstract

OVERVIEW: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 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. Model building consists of determining system parts, choosing the relationships that link these parts, specifying the mechanisms by which the parts interact, identifying missing information, and exploring the model behavior (Heemskerk et al. 2003). The model building process can be as enlightening as the model itself, because it reveals what is known and what is unknown about the connections and causalities in the systems under study.