|BROWN, JOEL - USDA-NRCS
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 11/1/2003
Publication Date: 1/15/2004
Citation: Bestelmeyer, B.T., Brown, J.R., Havstad, K.M., Tartowski, S.L. 2004. Managing land using ecological processes [abstract]. 3rd Annual Conference of the Quivira Coalition, January 15-17, 2004, Albuquerque, NM. p. 18-19.
Technical Abstract: Ranching in nature's image requires not only an understanding of what ecological processes may be important, but also a well-developed working knowledge of how those processes occur in space and time. While the scientific and ranching communities have devoted much attention to describing and managing important ecological processes like energy flow, nutrient transformation and cycling, water cycling, seed dispersal, etc., we have not spent a great deal of effort putting these processes into a management context with clear links to on-the-ground decision making. In this session, we will cover three important concepts that serve as a framework for interpreting information about ecological processes and suggest a means of organizing and, more importantly, testing whether management actions are having the desired effects. First, we will discuss the importance of variability in space and time when interpreting general or site-specific information for management decisions. For instance, rainfall infiltration rate is a good indicator of plant community and soil health. However, the rate of infiltration can vary dramatically within a paddock, within a plant community or even around an individual plant even though the entire area is subject to the same management and may be described as the same soil or the same ecological site. Knowing where and when to gather information about ecological processes is a critical component of management planning and effective monitoring. Second, the concepts of resistance and resilience are fundamental to interpreting ecosystem behavior and making management decisions designed to achieve goals and objectives. Resistance is the degree of disturbance (for instance, grazing) a plant community or soil can tolerate before it changes to another state. Resilience is the time it takes for a plant community or soil to return to its original state when the disturbance (for example, drought) is suspended. A qualitative understanding of resistance and resilience for specific sites is fundamental for making effective decisions about management and interpreting monitoring data. Finally, we will discuss the importance of ecological thresholds in managing grazing lands. Ecological thresholds can be viewed as critical periods in time when plant community and soil processes undergo significant and persistent changes in response to particular management or natural factors. Such changes are common when resistance and resilience are compromised. Once processes have changed and a new state is indicated, there is a very low probability that the community/soil will return to its original state without costly management intervention. Management models and monitoring systems must be designed with ecological thresholds in mind. The concepts of spatial and temporal variability, ecosystem resistance and resilience, and ecological thresholds can be combined to interpret information about ecological patterns and processes occurring in a ranch. While these concepts are general, the complexity of landscapes precludes the development of general, management-oriented mathematical models of rangeland behavior. Site-specific application of the concepts is a key component of effective and successful range management.