The study collectively of the , bioremediation, and/or biological augmentation of otherwise degraded environments.
Remediation represents removal of biotic or abiotic components of from environments, particularly things that don't 'belong' in those environments, e.g., the removal of from the . With bioremediation this removal is accomplished by organisms. See also .
Biological augmentation by contrast is the addition of biotic or abiotic components to environments, such as returning, if possible, species that have been lost from those environments in the course of previous . The goal here is to restore or otherwise increase species diversity by adding something to an environment, including species themselves, rather than to take something away.
Note that an environment need to be restored to a '' state to still be restored. Indeed, converting a to a garden also represents a degree of .
In any case, it is active that achieving, whole or in part, the restoration or indeed creation or recreation of an ecosystem.