| in order | 9 | other |
| to the health of some ecosystems | 5 | purpose |
| to thriving ecosystems | 5 | transitive-object |
| fire → be → necessary | 94 |
| fire → be → required | 26 |
| fire → be → necessity | 10 |
| fire → be → must | 7 |
| fire → be → need | 5 |
| fire → be → requirement | 4 |
| negative | neutral | positive |
| 0.243 | 0.598 | 0.159 |
| Raw frequency | 146 |
| Normalized frequency | 0.539 |
| Modifier score | 0.525 |
| Perplexity | 131.502 |