prevents the evaluation of integrated farm plans, plans that can address the range of soil functions and avoid the inconsistencies that can result from a focus on single best-management practices.
Current understanding of the effect of farming systems on soil and water quality is generally sufficient to identify the best available production practices or management systems; it is not, however, sufficient for making quantitative estimates of how much soil and water quality will improve as a result of the use of alternative practices or management methods. (National Research Council, 1993a, p. 11)
The debate over the use of public grazing lands is a manifestation of the larger issue of performance standards for managed ecosystems. Indeed, much of the controversy over Interior Secretary Bruce Babbit's proposal for rangeland reform centers on the development and application of "standards and guidelines" for rangeland managed by federal agencies. Rangeland Health observes that overgrazing, drought, erosion, and other human and naturally induced stresses have resulted in degradation in the past, though the "present state of health of U.S. rangelands is a matter of sharp debate" (National Research Council, 1994, p. 1).
Diverse rangeland ecosystems produce both tangible commodities with economic value (forage for livestock, for example) and intangible products, such as natural beauty and wilderness, that may have economic value but that also satisfy other important societal values. Protection of the capacity of rangelands to produce commodities and satisfy societal values is the congressionally established mandate for federal range management. In its report, the NRC committee attempted to identify criteria that could be used to monitor that capacity. As contrasted with cropped farming systems, which to greater or lesser extent depend on external inputs such as fertilizers, rangelands do not generally receive such supplements.
The capacity of rangelands to produce commodities and satisfy societal values depends on the integrity of internal nutrient cycles, energy flows, plant community dynamics, an intact soil profile, and stores of nutrients and wastes. (National Research Council, 1994, p. 5)
The report defines rangeland health as "the degree to which the integrity of the soil and the ecological processes of rangeland ecosystems are sustained" (National Research Council, 1994, p. 2), and it argues for the establishment of a minimum standard of rangeland management that would protect against humaninduced loss of rangeland health. This minimum is to be an ecological standard,