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Biodiversity & Conservation

, Volume 6, Issue 9, pp 1203–1217 | Cite as

The impact of large herbivores on floral composition and vegetation structure in the Naukluft Mountains, Namibia

  • ANTJE BURKE
Article

Abstract

Floral composition and vegetation structure were investigated on the Naukluft Mountain Plateau to determine (i) whether or not grazing has had an impact on the flora of the Naukluft Mountains during the last two decades and (ii) if so, whether vegetation recovery is influenced by the nature of the rainy season. Vegetation subjected to grazing to large herbivores and vegetation excluded from grazing for 18 and 19 years was compared. Based on classification (TWINSPAN) and ordination (detrended and canonical correspondence analysis) of 20, 10 × 10 m stands within and outside exclosures in two seasons, a clear difference in floristic composition between grazed and not grazed areas was indicated. Although neither the height of the vegetation, not the growth form spectrum differed significantly between grazed and not grazed sites, leaf-succulents were much more abundant when grazing was excluded. This suggests that changes in the vegetation due to grazing pressure have occurred in the last two decades, but the degree of grazing impact is not severe and may be part of the natural savanna ecosystem of the Naukluft Mountains. Whether this trend also occurs in other vegetation types in the Naukluft Mountains remains to the investigated.

grazing pressure Namib fringe rangeland management semi-arid savanna vegetation 

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Copyright information

© Chapman and Hall 1997

Authors and Affiliations

  • ANTJE BURKE
    • 1
  1. 1.National Botanical Research InstituteWindhoekNamibia

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