Table 1.
Examples of root traits modelled using the Entity‐Quality model (‘EQ’ model).
| Common trait name | Formalised trait name | Entity | Quality | Frequent abbreviation | Commonly used unit |
|---|---|---|---|---|---|
| Specific root length | Root specific length | Root | Specific length | SRL | m g−1 |
| Root nitrogen concentration | Root nitrogen content per unit mass | Root | Nitrogen content per unit mass | RNC | mg g−1 |
| Root hair density | Root hair density | Root | Hair density | – | mm−1 |
| Vertical root mass distribution index | Root vertical mass distribution index | Root | Vertical mass distribution index | β | no units |
| Nitrogen‐fixation ability | Root nitrogen‐fixation ability | Root | Nitrogen‐fixation ability | – | categories: N2 fixing, non‐N2 fixing |
Note that the generic entity ‘root’ is used in these examples, but that most qualities could be associated to different entities such as ‘first‐order root’ or ‘transport root’.