Functional diversity response to geographic and experimental precipitation gradients varies with plant community type

Precipitation is a primary determinant of plant community structure in drylands. However, the empirical evidence and predictions are lacking for how plant functional diversity in desert and steppe communities respond to altered precipitation regimes.

We examined how precipitation changes along the natural and experimental gradients affect different components of functional diversity in desert-shrub and steppe-grass communities. We compared the associations of precipitation changes with community-weighted means (CWM) of six traits, functional divergence (FDvar) of each single-trait, and multi-trait functional richness (FRic) and dispersion (FDis) for shrub and grass communities along the natural and experimental gradients. We also disentangle the roles of species turnover and intraspecific variations in affecting the responses of different functional diversity to precipitation changes.

We found that in general, the similar responses of functional traits or diversity to both the n...