PS 88-86
Temporal scales of coupled ecosystem processes provide a benchmark for alternate ecosystem states: Photosynthesis and decomposition in a model micro-ecosystem

Friday, August 14, 2015
Exhibit Hall, Baltimore Convention Center
Matthew Lau, Harvard Forest, Harvard University, Petersham, MA
Aaron M. Ellison, Harvard Forest, Harvard University, Petersham, MA

Community dynamics can lead to sudden or recalcitrant ecosystem state changes, but our understanding of the general properties and our ability to predict would benefit greatly from a model system that permits both realistic models and manipulative studies. Here, we further develop and apply a micro-ecosystem model based on the food web of the pitcher forming carnivorous, Northern Pitcher Plant, Sarracenia purpurea, to simulate oxygen production of how press perturbations lead to ecosystem state changes.  


We found three main results:  1. The micro-ecosystem model reproduced the gross behavior of the pitcher plant food web. 2. Sensitivity analysis revealed several parameter combinations that lead to an alternative state for oxygen production. 3. Furthermore, the parameter combinations leading to the alternative state depended on the difference in temporal scale of the photosynthesis and decomposition rates. These results point to a general framework for identifying potential ecosystem state changes. In particular, the identification of interacting processes that may operate at different temporal scales provides a predictive benchmark for alternate ecosystem states.