| A | B |
|---|
| conservation | wise, intentional management of a resource to prevent depletion |
| emission | the release of waste products, typically gasses into the atmosphere |
| endangered | in danger of becoming extinct |
| exotic species | species released into a place where they had never been before |
| extinct | having died out; leaving no more left |
| filtration | removal of undesirable particles through a semi-permeable membrane |
| preservation | intentional management of a resource to prevent its elimination |
| purification | the decontamination of a resource in order to make it useful again |
| stewardship | management of resources for future generations |
| threatened | in danger of becoming endangered |
