Ecological transition in Arizona's subalpine and montane grasslands

Abstract

Important components of Southwest forest ecosystem are subalpine and montane grassland communities, Grassland communities provide habitat diversity for wildlife, forage for domestic livestock and wildlife, and contribute to the visual quality of an area. The objectives of this research were to determine if: 1) vegetation attributes and soil-surface cover variables of interest have changed, or if they have maintained equilibrium relative to conditions in 1913 through 1915; and 2) a correlation exists between the ecological diversity-stability hypothesis (Huston 1979, Pimm 1984, McNaughton 1994, Tilman 1994). The hypotheses tested were: 1) subalpine and montane grasslands have changed since 1913 through 1915, specifically, relative native species richness has declined and relative species composition has shifted, while annual and exotic species richness has increased with concurrent increases in exposed soil surface area; and 2) shifts in species composition and increases in species richness and exposed soil surface are not evidence of ecological community stability.

Parent Publication

• Land Stewardship in the 21st Century: The Contributions of Watershed Management; 2000 March 13-16; Tucson, AZ

Citation

White, Michael R. 2000. Ecological transition in Arizona's subalpine and montane grasslands. In: Ffolliott, Peter F.; Baker Jr., Malchus B.; Edminster, Carleton B.; Dillon, Madelyn C.; Mora, Karen L., tech. coords. Land Stewardship in the 21st Century: The Contributions of Watershed Management; 2000 March 13-16; Tucson, AZ. Proc. RMRS-P-13. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 273.