PARENT SESSION
Oral Session #53: Elevated CO₂: Communities, ecosystems, soils.
Presiding: G. Lin
Wednesday, August 7. 8:00 AM to 11:30 AM. Coconino Meeting Room, TCC.

Models and mechanisms linking carbon, water and nutrient cycles under elevated CO₂.

Finzi, Adrien^*,1, ¹ Boston University, Boston, MA

ABSTRACT- With studies of elevated CO₂ in terrestrial ecosystems, ecologists can understand how carbon availability affects hydrologic and nutrient cycles. I review a series of conceptual and quantitative models that propose both positive and negative feedback effects of elevated CO₂ on carbon, nitrogen and phosphorus biogeochemistry and the hydrologic cycle. While there is a clear conceptual basis for these different models, the mechanisms these models propose are often poorly supported by the available data. Several factors complicate data interpretation: lack of statistical power, poor integration from an ecosystem perspective, and site history. The individualistic response of different research sites makes it difficult to generalize our understanding of the ecosystem consequences of elevated CO₂. I propose a series of standardized measurements that could aid in drawing generalizeable conclusions from current studies of elevated CO₂. I integrate this information into new conceptual models that could provide a series of testable hypothesis in elevated CO₂ research.

KEY WORDS: elevated CO₂, ecosystem, nitrogen, phosphorus