Canopy Gap Characteristics and Drought Influences in Oak Forests of the Coweeta Basin

  • Authors: Clinton, B.D.; Boring, L.R.
  • Publication Year: 1993
  • Publication Series: Miscellaneous Publication
  • Source: Ecology, 74(5), 1993, pp. 1551-1558

Abstract

Canopy gaps in southern Appalachian mixed-Quercus forests were characterized to assess the impact of the 1985-l988 record drought on patterns of tree mortality in relation to topographic variables and changes in overstory composition. Using permanent transects, we sampled 68 canopy gaps within the Coweeta Basin. Among l-5 yr old gaps, the most common gap type was the 1-yr-old single-tree snag, accounting for 49% of all gaps sampled; 65% of all gaps occurred within 2 yr of the drought peak. Gap area ranged from 40 to 850 m2, averaged 239 m2, with a median of 152 m2. Analysis of 1988 color infrared (IR) aerial imagery yielded a gap formation rate of 0.8 gaps ha-1yr-1 in mixed-Quercus stands affecting 2.00/o of the area in this forest type in 1988. The most frequent gap-forming species were Quercus coccinea, Q. rubra, and Q. velutina, respectively. Evidence suggests that moisture stress brought on by severe drought increases the susceptibility of Quercus species to the shoe-string fungus Armillaria mellea, which may result in significant shifts in canopy composition in these forests.

  • Citation: Clinton, B.D.; Boring, L.R. 1993. Canopy Gap Characteristics and Drought Influences in Oak Forests of the Coweeta Basin. Ecology, 74(5), 1993, pp. 1551-1558
  • Keywords: canopy gaps, Coweta, disturbance, drought, mixed-oak forests, predisposal, southern Appalachians, tree mortality
  • Posted Date: April 1, 1980
  • Modified Date: August 22, 2006
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.