Grover, J. P. University of Texas at Arlington, grover@uta.edu
Codeco, C. P. University of Texas at Arlington, claudia@uta.edu

 
RESOURCE COMPETITION AND RESOURCE RATIOS: HOW INTER- AND INTRASPECIFIC VARIATION OF MICROBIAL STOICHIOMETRY ILLUMINATES AN ECOLOGICAL PROCESS
 
Principles of ecological stoichiometry play an important role in studying resource competition among algae and other microorganisms. The classical theory of competition for two nutrient resources is based on interspecific variation in the stoichiometry of microbial cell composition. This theory translates the stoichiometry of abiotic nutrient supply into predictions of competitive exclusion or coexistence of microbial populations. The classical theory can be extended in several ways that illuminate contemporary issues in the study of competition. Modifying theories of "pure competition" to include commensal fluxes of resources produced by one or more populations permits modeling of the interactions between algae, heterotrophic bacteria, and phagotrophic organisms. Intraspecific variation in cellular stoichiometry is related to storage of resources, and explicitly modeling these variations allows transient states and nonequilibrium competition to be modeled with high fidelity. Laboratory studies of spatial gradients in nutrient supply rations show that intraspecific variations in cellular stoichiometry play a role in spatially structured population dynamics and competition. Incorporating these latter processes in theoretical models poses major challenges.
 
Day: Wednesday, Feb. 3
Time: 03:30 - 03:45pm
Location: Sweeney Center
 
Code: SS49WE0330S