| by two different groups of microorganisms | 3 | other |
| in nitrification | 2 | temporal |
| ammonia → be → oxidized | 12 |
| ammonia → be oxidized to → nitrate | 7 |
| negative | neutral | positive |
| 0.436 | 0.528 | 0.036 |
| Raw frequency | 19 |
| Normalized frequency | 0.414 |
| Modifier score | 0.500 |
| Perplexity | 29.022 |