PARENT SESSION
Symposium #33: The ecology and evolution of coupled energy and material flows: integration of multiple scales and multiple biota.
Organized by: JD Schade, T Markow, and S Hobbie
Friday, August 9. 9:00 AM to 12:00 PM. Crystal Ballroom, TCC.
Magnification of ecosystem function by Darwinian selection on organism-nutrient interactions.
HEDIN, LARS*,1, LEVIN, SIMON1, BUTTEL, LINDA2, 1 Princeton University, Princeton, New Jersey2 Cornell University, Ithaca, New York
ABSTRACT- At levels of ecosystems, predictable macroscopic patterns in nutrient cycles emerge despite the complex interplay of myriad biotic and abiotic elements, and despite the propensity for evolution to alter organism-nutrient relations over time. Such emergent properties define the ecosystems themselves, and provide the contexts within which species interact and evolve. We have developed a series of models that explore how ecosystem-level patterns develop and are maintained based on localized organism-nutrient interactions and top-down feedback effects. We here report how different physiological strategies among terrestrial plants act to either magnify or eliminate particular ecosystem functions, and how these interactions depend on Darwinian selection at the level of individuals. We find that explicit structure and localized selection rules are essential elements for explaining differences in nutrient cycling among different forest types, and in optimal stoichiometery of individual species. Magnification of plant functional strategies include traditional strategies of individual or cooperative maximization, but also Nash-type strategies that appear dilutive at the ecosystem level.
KEY WORDS: Biogeochemistry, Nutrient cycles, Evolution, Plant strategies