The 2008 Joint Meeting of the Society for Range Management and the America Forage and Grassland Council. |
Tuesday, January 29, 2008 - 3:10 PM
Resilience and Feedbacks within A Deep Sand Savannah Ecological Site
Pat L. Shaver, West National Technology Support Center, USDA-NRCS, 1201 NE Lloyd Blvd. Suite 1000, Portland, OR 97232
The use of state-and-transition models is becoming a common framework for organizing information used to make management decisions. Recently a move to incorporate the concepts of resilience into the model is gaining momentum. Resilience to change is based on the amount of disruption needed to change a set of mutually reinforcing processes to a different set of mutually reinforcing processes. This change in emphasis from thresholds to resilience allows the manager to focus on within state dynamics that can be manipulated by management actions, rather than on after the fact actions to repair or restore lost functions or values. The mutually reinforcing processes or feedbacks must be identifiable and recognizable in order for management to have the opportunity to adapt to changes to prevent the likelihood of threshold limits from being crossed. The study of a Deep Sand Savannah ecological site in central New Mexico provides an opportunity to discuss the dynamics of the state-and-transition model, the feedback mechanisms that maintain those dynamics and the possible at risk community phases and the triggers that may begin the shift from one set of feed back mechanisms to another. Management options associated with the changes of the feed back mechanisms and resulting change from one state to another differ. Identification of the feed back mechanisms and triggers may provide an understanding of needed management actions and implications for management or restoration of previous states.