Figure 3.

(a and b) Location of major plant functional groups (crossing biomes) on the three-dimensional leaf trait response surface for field data (a) and literature data (b). Major groups considered were: herbs (herbaceous species in all tundra, grassland, and forested ecosystems), pioneers (pioneer trees in boreal, temperate, and tropical forests), broad-leaved deciduous (mostly mid- to late successional temperate and tropical woody species that are deciduous; plus tropical broad-leaved evergreen tree species with leaf life-span <11 months), broad-leaved evergreen (woody broad-leaved species with leaf life-span >1 year, usually common to resource-poor environments), and needle-leaved evergreen (includes all evergreen coniferous species).