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EPA EcoBox

EPA EcoBox Tools by Effects

The purpose of an ecological risk assessment (ERA) is to evaluate the likelihood that adverse ecological effectsHelpadverse ecological effectsChanges that are considered undesirable because they alter valued structural or functional characteristics of ecosystems or their components. An evaluation of adversity may consider the type, intensity, and scale of the effect as well as the potential for recovery (U.S. EPA, 1998). may be occurring or are occurring as a result of exposure to one or more stressors. This tool set describes available tools to identify and evaluate stressor-receptor relationships—or evidence that exposure to stressors causes an observed response—and potential ecological effects. 


See information and tools related to aquatic effects



See information and tools related to terrestrial effects