Vegetatio

, Volume 55, Issue 3, pp 129–139

Disturbance and vegetation response in relation to environmental gradients in the Great Smoky Mountains

  • M. E. Harmon
  • S. P. Bratton
  • P. S. White
Article

DOI: 10.1007/BF00045013

Cite this article as:
Harmon, M.E., Bratton, S.P. & White, P.S. Vegetatio (1984) 55: 129. doi:10.1007/BF00045013

Abstract

In constructing models of species and community distributions along environmental gradients in the Great Smoky Mountains, R. H. Whittaker (1956) focused on old-aged, apparently stable, natural communities. More recent studies indicate that disturbance gradients potentially influence and are influenced by the complex environmental gradients of Whittaker's original models. Using primarily fire and exotic species invasion as examples, this paper shows: 1) disturbance parameters vary along the topographic, elevation and moisture gradients in the Great Smoky Mountains in much the same way as temperature, moisture and solar radiation change; 2) species composition at different locations along the major environmental gradients is partially determined by the disturbance parameter; 3) species characteristics such as mode of reproduction are often correlated with specific disturbance parameters; 4) functional aspects of ecosystem response to disturbance vary along environmental gradients; and 5) man-caused disturbance may vary along environmental or biotic gradients. Since disturbance gradients may parallel physical environmental gradients, the two may be difficult to distinguish. Modification of disturbance frequencies along major environmental gradients may result in slow shifts in the distribution of both individual species and whole communities.

Key words

Community structureDisturbanceGradient analysisSuccessional strategiesTemperate forest

Copyright information

© Dr W. Junk Publishers 1983

Authors and Affiliations

  • M. E. Harmon
    • 1
  • S. P. Bratton
    • 2
  • P. S. White
    • 3
  1. 1.Department of Botany and Plant PathologyOregon State UniversityCorvallisU.S.A.
  2. 2.U.S. National Park Service, Cooperative Unit, Institute of EcologyUniversity of GeorgiaAthensU.S.A.
  3. 3.Uplands Field Research LabGreat Smoky Mountains National ParkGatlinburgU.S.A.