Assessing Aquatic Ecosystem Response to Stress

Developing management strategies for sustainable riverine ecosystems, including finding practical solutions for endangered aquatic species preservation, requires an improved understanding of riverine ecosystem behavior under stress. This research seeks to provide a methodology to quantify temporal and spatial changes in ecosystem health induced by environmental stresses. A mechanistic ecosystem response model will be utilized to quantify impacts of natural and anthropogenic stresses, singly or in combination, on sensitive aquatic species. This ecosystem response model is being created by incorporating an ecological routine into an existing hydrodynamic and water quality modeling framework. Initial application of the ecosystem response model investigates impacts of flow regime, water temperature, and salinity on survival, growth, and migration of juvenile chinook salmon in the Sacramento River-San Francisco Bay-Delta system. Progress is reported on development and application of this methodology for determining relationships between stress changes and aquatic ecosystem responses.