Submitted to: International Rangeland Congress
Publication Type: Proceedings
Publication Acceptance Date: January 30, 2011
Publication Date: N/A
Interpretive Summary: Rangeland ecosystems are highly complex systems that have variable soils, weather, topography, grazing animals, wildlife and vegetation which often results in difficult management problems due to differences in goals, values, and decision-making strategies. In addition to this complexity, there is considerable uncertainty associated with climate change impacts on weather. Land managers would like to know where and to what extent rangeland vegetation may change in response to climate changes, but our ability to project the path of future vegetation changes due to climate change and how management interacts is poorly developed. One emerging tool is state-and-transition models which function to organize current understanding of management influences on vegetation and how changes in vegetation impact structure and function of rangelands. These state-and-transition models function as decision support tools for land managers to showcase how management can prevent the occurrence of non-desirable vegetation and promote desirable vegetation. Further refinement of state-and-transition models is needed to incorporate latest experimental findings addressing climate change scenarios in the context of range management practices and their combined effects on rangelands.
Technical Abstract: Rangeland ecosystems are multifaceted biophysical systems with highly variable soils, weather, landforms, animals, and vegetation that are manifest in complex management options which involve diverse human goals, values, beliefs and decision-making strategies. Overlaying this vast background variability on rangelands for resource users is the emergent context of climate change and the resultant increased uncertainty in weather and atmospheric carbon dioxide (CO2) levels. One of the most critical problems is where and to what extent rangeland vegetation may change in response to climate changes, and our ability to project the trajectory of future vegetation changes due to combined management and climate change is not well developed. State-and-transition models are a means of organizing current understanding of management influences on states of vegetation and transitions and thresholds through alterations in ecological processes, and they function as decision support tools for resource managers to prevent the occurrence of undesirable states and promote the occurrence of desirable states. Development of state-and-transition models that incorporate the latest experimental findings will allow us to explore and test these and other climate change scenarios in the context of range management practices and their combined effects on rangelands, and should significantly advance our ability to develop optimal management practices to deal with climate change.