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Folia Geobotanica

, Volume 35, Issue 4, pp 363–373 | Cite as

Patterns of change in reed cover and distribution in a seasonal riverine wetland in South Africa

  • Karen A. Kotschy
  • Kevin H. Rogers
  • Andrew J. Carter
Article

Abstract

Phragmites mauritianus is the dominant herbaceous species colonizing riverine habitats in the Kruger National Park, South Africa. These perennial systems are characterized by high annual and seasonal flow variability and a complex mosaic of patches of reeds, sand, water, rock and other vegetation. Patterns of increase and decrease in reed cover in the Letaba River were determined from aerial photographs covering a 54-year period. An initial period of reed expansion (1942–1965) was followed by a period of reed loss (1965–1977) and subsequent gradual re-establishment (1977–1996). A spatially explicit analysis of changes in reed distribution over an 8-year period (1988–1996) showed that patches of reed vegetation are, in the short term, highly dynamic elements within the river landscape. Analyzing short-term, small-scale change provides information which is not obtainable from long-term, large-scale studies. We propose that causes of reed expansion or decline cannot be determined without an understanding of both long- and short-term patterns of change.

Keywords

Geographical Information System Kruger National Park Letaba River Phragmites mauritianus 

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Copyright information

© Institute of Botany 2000

Authors and Affiliations

  • Karen A. Kotschy
    • 1
  • Kevin H. Rogers
    • 1
  • Andrew J. Carter
    • 1
  1. 1.Centre for Water in the EnvironmentUniversity of the Witwatersrand, JohannesburgWitsSouth Africa

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