Department of Biology, University of Utah, Salt Lake City, UT 84112.
Species respond in diverse ways to sporadic and unpredictable pulses of resource availability.
Here we examine the potential consequences of this functional diversity to competition and the structuring of communities. We developed a model that encapsulates species differences in their ability to utilize rainfall events at different times of the year. Key features of this model include patterns of biomass allocation between leaf, stem and root biomass in shallow and deep soil, root diameter, stomatal control, and tradeoffs associated with these functions. The model enabled us to estimate seasonal water utilization by the different species, and the degree of competition we expect to see based on water use. Our results are generally in agreement with the results of our field experiments.