Developing Stressor-Response Relationships
The common management goal for all aquatic ecosystems is to maintain ecological integrity by protecting these systems against degradation of habitat, loss of ecosystem functions and services, and reduced biodiversity. To this end, environmental managers must be able to: 1) assess the condition of an aquatic resource and determine its degree of impairment, 2) diagnose the causes of impairment if observed, 3) forecast the effects of changes in stressor levels, and 4) develop and implement remediation and maintenance strategies. To accomplish these, managers must be able to characterize aquatic systems, knowing the appropriate reference conditions against which to compare their assessments, have the diagnostic tools necessary to ascertain causes, and understand specific aquatic systems well enough to forecast the effectiveness of potential remediation efforts. The information, methods, and tools needed by the Agency, States, and Tribes to conduct these activities are incompletely developed with respect to many of the Nation's aquatic resources.
NHEERL's Aquatic Stressors research focuses on the effects of the habitat alteration, nutrients, suspended and bedded sediments, and toxic chemicals. These stressors are cited most often in failures of aquatic resources to meet their designated uses, and States and Tribes commonly report these stressors in their 303(d) lists of impaired waters under the Clean Water Act. However, the methods used to assign causation are inconsistent at best. Therefore, Aquatic Stressors research will also develop diagnostic tools for a decision support system for environmental managers. AED is the lead division amongst NHEERL's four ecology divisions for Suspended and Bedded Sediments research, but is contributing substantially to the other research areas as well.