PARENT SESSION
Oral Session #2: Thermodynamics and Complexity. Presiding: T. Allen.
Monday, August 6, 2001. 8:00 AM to 11:45 AM. Madison Ballroom D.

Inverse analysis in ecology: A novel approach to untangling biocomplexity.

Luo, Yiqi¹, ¹

ABSTRACT- Ecologists are dealing with complex systems all the time. But we lack of a general approach to untangling biocomplexity. My talk will show that inverse analysis may be a very powerful approach to studying complex systems. Inverse analysis has been widely used in other scientific disciplines but has not been applied in ecology. The approaches fundamentally focus on data analysis for pattern recognition and mechanism identification. Its counterpart is the forward analysis, which is usually accomplished using simulation models. The latter predicts systems behavior with given model structure and a set of prescribed parameter values. Generally speaking, the forward analysis asks what a model can tell us about the biocomplexity of a system in question whereas the inverse analysis asks what the data can tell us about the same system. Combining the two approaches, we are able to probe mechanisms underlying the system. In this talk, I will use the Duke Forest free-air CO₂ enrichment (FACE) study as an example to illustrate (1) the need of inverse analysis, (2) inverse analysis for characterization of carbon structure in the rhizosphere; and (3) inverse analysis for parameter estimation. Applications of the inverse analysis to the Duke FACE project have offered insights into several long-standing issues in ecosystems ecology, such as quantification of root exudation, root turnover, and sustainability of carbon sequestration in terrestrial ecosystems.

KEY WORDS: biocomplexity, data analysis, carbon, global change