| Answer | Crossword Clue |
|---|---|
| REEFS | Underwater ecosystems |
| BIODOMES | Closed ecosystems |
| TERRARIA | Microcosmic ecosystems |
| FENS | Alkaline ecosystems |
| BIOMES | Large ecosystems |
| REEFS | Some endangered ecosystems |
| FAUNAS | Parts of ecosystems |
| EPA | Org. concerned with ecosystems |
