| Ecological measure | Definition |
| Environmental volume | Three-dimensional range of a species in an
ordination space based on 53 environmental measures for each of 92
plots. The range on each axis was the distance of the sites with the largest and smallest axis scores that contained that species. |
| Abundance | Mean cover value of a species, based on a six-point Braun-Blanquet scale, for all plots in which the species appeared. |
| Ecological breadth | Classification of each species into one of four groups based on its general distribution: wet-grassland specialist (WGS), wet-grassland generalist (WGG), mesic-habitat generalist (MHG), and generalist (G). |
| Wet-grassland specialists | Species characteristic of Iberian Atlantic climates. |
| Wet-grassland generalists | Species that are found in a range of mesic habitats. |
| Mesic-habitat generalists | Species that are found in a range of mesic habitats. |
| Generalists | Species that are typically found in nonwetland habitats. |
| Habitat occupancy | The percentage of plots within an environmental volume that were occupied by a given species. |
| Regional range | The extent of a species' range within the Iberian Peninsula, in km2. |
| Continental range | The number of geographic units across Europe and the Mediterranean basin with a recorded presence for a species. |