, Volume 94, Issue 2, pp 133–140 | Cite as

Successional trajectories of a grazed salt desert shrubland

  • S. G. Whisenant
  • F. J. Wagstaff


Successional trajectories through the statistical space of ordinations were used to examine response to grazing in salt desert shrub communities of western Utah, USA. Relative cover data were periodically collected over a 53 year period from grazing exclosures and pastures grazed with light or heavy stocking rates in fall or spring (4 grazing treatments). Two-way indicator species analysis was used to select the 98 most similar plots (24 m2) from among 358 plots in 1935. Foliar cover of 23 species on those 98 plots was followed at irregular intervals over 53 years, resulting in 709 plot-time samples. Successional trajectories were developed for each grazing treatment with ordinations from detrended correspondence analysis. Grazing season had a more pronounced influence on floristic trajectories than did grazing intensity. These ordinations suggest grazing season was an important factor regulating response to grazing and identify annual March-April grazing as an important cause of retrogression in the salt desert shrub ecosystem.


Sheep grazing Ordination 



Desert Experimental Range


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  1. Austin, M. P. 1977. Use of ordination and other multivariate descriptive methods to study succession. Vegetatio 35: 165–175.Google Scholar
  2. Austin, M. P. 1985. Continuum concept, ordination methods, and niche theory. Ann. Rev. Ecol. Syst. 16: 39–61.Google Scholar
  3. Austin, M. P., Williams, O. B. & Belbin, L. 1981. Grassland dynamics under sheep grazing in and Australian Mediterranean type climate. Vegetatio 47: 201–211.Google Scholar
  4. Bassett, P. A. 1980. Some effects of grazing on vegetation dynamics in the camargue, France. Vegetatio 43: 173–184.Google Scholar
  5. Clary, W. P. 1985. Fifty-year response to grazing in the lowshrub cold desert of the Great Basin, U.S.A. In: P. J. Ross, P. W. Lynch, and O. B. Williams (eds.) Proc. 2nd Int. Rangeland Congr., Melbourne.Google Scholar
  6. Collins, S. L. & Adams, D. E. 1983. Succession in grasslands: thirty-two years of change in a central Oklahoma tallgrass prairie. Vegetatio 51: 181–190.Google Scholar
  7. del Moral, R. 1980. On selecting indirect ordination methods. Vegetatio 42: 75–84.Google Scholar
  8. Gauch, H. G. 1982. Multivariate analysis in community ecology. Cambridge Univ. Press. Cambridge.Google Scholar
  9. Goodrich, S. 1986. Vascular plants of the Desert Experimental Range, Millard County, Utah. USDA, FS, Intermountain Research Station, Gen. Tech. Rep. INT-209.Google Scholar
  10. Harper, K. T. 1959. Vegetational changes in a shadscale-winterfat plant association during twenty-three years of controlled grazing. M.S. Thesis. Brigham Young University, Provo, UT. 68 p.Google Scholar
  11. Hill, M. O. 1979. TWINSPAN. A FORTRAN program for arranging multivariate data in an ordered two-way table by classification of the individuals and attributes. Section of Ecology and Systematics, Cornell Univ., Ithaca, NY.Google Scholar
  12. Hill, M. O. & GauchJr., H. G. 1980. Detrended correspondence analysis: an improved ordination technique. Vegetatio 42: 47–58.Google Scholar
  13. Holmgren, R. C. 1973. The Desert Experimental Range: description, history, and program. Arid Shrublands. Proc. Third Workshop of the United States/Australia Rangelands Panel. Tucson, AZ.Google Scholar
  14. Holmgren, R. C. & Hutchings, S. S. 1972. Salt desert shrub response to grazing use. pp. 153–165 in Wildland Shrubs. Their Biology and Utilization. USDA, FS, gen. Tech. Rep. INT-1.Google Scholar
  15. Hurlbert, S. H. 1984. Pseudoreplication and the design of ecological field experiments. Ecol. Monogr. 54: 187–211.Google Scholar
  16. Hutchings, S. S. & Stewart, G. 1953. Increasing forage yields and sheep production on Intermountain winter ranges. USDA, Circular No. 925.Google Scholar
  17. Malanson, G. P. & Trabaud, L. 1987. Ordination analysis of components of resilience of Quercus coccifera garrigue. Ecol. 68: 463–472.Google Scholar
  18. Norton, B. E. 1978. The impact of sheep grazing on long-term successional trends in salt desert shrub vegetation of southwestern Utah. In: D. A. Hyder (ed.) Proc. 1st Int. Rangeland Congr., Denver, Colorado.Google Scholar
  19. Stewart, G. & Hutchings, S. S. 1936. The point-observation-plot (square-foot density) method of vegetation survey. Am. Soc. Agron. J. 28: 714–722.Google Scholar
  20. Stewart, G., Cottam, W. P. & Hutchings, S. S. 1940. Influence of unrestricted grazing on northern salt desert plant associations in western Utah. J. Agric. Res. 60: 289–316.Google Scholar
  21. Turner, G. T. 1971. Soil and grazing influences on a salt desert shrub range in western Colorado. J. Range Manage. 24: 31–37.Google Scholar
  22. van der Maarel, E. & Werger, W. J. A. 1978. On the treatment of succession data. Phytocoenosis 7: 257–278.Google Scholar
  23. West, N. E. 1979. Survival patterns of major perennials in salt desert shrub communities of southwestern Utah. J. Range Manage. 32: 442–445.Google Scholar

Copyright information

© Kluwer Academic Publishers 1991

Authors and Affiliations

  • S. G. Whisenant
    • 1
  • F. J. Wagstaff
    • 2
  1. 1.Department Range ScienceTexas A&M UniversityCollege StationUSA
  2. 2.U.S.D.A., Forest ServiceIntermountain Research StationProvoUSA

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