MANAGEMENT TECHNOLOGIES FOR ARID RANGELANDS
Location: Range Management Research
Title: Threshold models in restoration – can we ever predict threshold responses?
Submitted to: Society for Ecological Restoration Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 25, 2009
Publication Date: August 23, 2009
Citation: Bestelmeyer, B.T. 2009. Threshold models in restoration – can we ever predict threshold responses [abstract]. 19th Conference of Society for Ecological Restoration International, August 23-27, 2009, Perth, Western Australia, Australia. http://www.seri2009.com.au/pages/Wednesday_am.pdf.
Land managers and scientists often ask: “How do I identify the threshold?” or “Where is the threshold?” Such questions presume a great deal about the nature of thresholds that are, as yet, not generally understood and not necessarily general at all. In this talk, I review how the threshold concept has been considered in land management and argue five points. 1) Attempting to predict threshold responses is likely to be a waste of time in many cases. 2) We have not yet produced an adequate number of case histories about the consequences, scales, rates, and mechanisms of threshold behavior within different kinds of ecosystems, so it is difficult to structure monitoring programs to detect threshold responses. 3) Managing for resilient conditions, with attention to slow social and ecological variables, to minimize the risk of crossing a threshold is potentially useful but is controversial for managers. 4) We have a dim understanding of how inherent (i.e., not management-related) variations in landscapes influence threshold responses, but such understanding can be used to guide planning. 5) Recognizing the consequences of post-threshold states for restoration actions is the most straightforward use of the threshold concept at present. Examples are drawn from restoration approaches in the southwestern United States and elsewhere to support these assertions.