ABSTRACT
The chapter provides a framework for the analysis of environmental resource management problems that incorporate ecosystem models as an essential component. It describes a regional environmental quality management system, including the range of management options available to society for maintaining, or improving, environmental quality. The chapter indicates how all the components of the system, especially the ecosystem models, may be linked together within the same conceptual framework. It presents considerations for managing aquatic ecosystems, and a set of questions for the symposium participants relating to the current state-of-the-art of ecosystem models developed for management purposes. The ecosystem models can be employed in two basic ways. First, they can be used, by themselves, as tools for predicting alternative states of the natural world, given various sets of residuals input levels and distributions. Second, ecosystem models can be used in conjunction with optimization, or management, models with 'optimal' levels and distributions of residuals discharges selected by the management model.
