Box 9E. 1 Continued FIGURE 2. The C-S-R triangle model (Grime 1979). The
strategies at the three corners are C, competiti- winning species; S,
stress-tolerating s- cies; R, ruderalspecies. Particular species can
engage in any mixture of these three primary strategies, and the m- ture
is described by their position within the triangle. comment briefly on
some other dimensions that Grime's (1977) triangle (Fig. 2) (see also
Sects. 6. 1 are not yet so well understood. and 6. 3 of Chapter 7 on
growth and allocation) is a two-dimensional scheme. A C--S axis (Com-
tition-winning species to Stress-tolerating spe- Leaf Economics Spectrum
cies) reflects adaptation to favorable vs. unfavorable sites for plant
growth, and an R- Five traits that are coordinated across species are
axis (Ruderal species) reflects adaptation to leaf mass per area (LMA),
leaf life-span, leaf N disturbance. concentration, and potential
photosynthesis and dark respiration on a mass basis. In the five-trait
Trait-Dimensions space,79%ofallvariation worldwideliesalonga single main
axis (Fig. 33 of Chapter 2A on photo- A recent trend in plant strategy
thinking has synthesis; Wright et al. 2004). Species with low been
trait-dimensions, that is, spectra of varia- LMA tend to have short leaf
life-spans, high leaf tion with respect to measurable traits. Compared
nutrient concentrations, and high potential rates of mass-based
photosynthesis. These species with category schemes, such as
Raunkiaer's, trait occur at the ''quick-return'' end of the leaf e-
dimensions have the merit of capturing cont- nomics spectrum.
