|Fox, H - NRCS|
Submitted to: Multiple Objective Decision Support Systems for Land, Water, and Environment
Publication Type: Abstract Only
Publication Acceptance Date: March 3, 1999
Publication Date: N/A
Technical Abstract: A multiple objective decision support system (DSS) is used to evaluate two alternative grazing systems, continuous and short-duration, with respect to environmental criteria. A structure for determining Rangeland Health, the degree to which the integrity of the soil and ecological processes of rangeland ecosystems are sustained, is presented. The methodology is applied to four watersheds within the Santa Rita Experimental Range in southeastern Arizona, U.S.A. Rangeland Health is evaluated by summing the results from three functional categories: watershed function and soil stability, distribution of nutrient cycling and energy flow, and recovery mechanisms. Seventeen individual attributes are allocated to one or more of the three categories. Each attribute can be assigned an importance order within a category independent of its ranking in another category. A simple algorithm based on linear and dynamic programming is implemented in a computer spreadsheet to quickly compute the possible sites. The method is applied in the context of a hierarchical arrangement of the individual indicators within each functional category. The overall rating is computed without the need to assign explicit weights to the individual indicators. Surface runoff, sediment yield, and plant density, frequency and cover data collected over a 23 year period are used to provide a quantitative measure to evaluate the relevancy of the qualitative range assessment process.