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Plant Ecology

, Volume 212, Issue 9, pp 1407–1418 | Cite as

Can heavy grazing on communal land elevate plant species richness levels in the Grassland Biome of South Africa?

  • M. C. RutherfordEmail author
  • L. W. Powrie
Article

Abstract

A common perception, particularly in South Africa, is that heavily and continuously grazed communal land leads to degradation and loss of plant diversity when compared to commercial rangeland farming or conservation areas. We focus on whether this applies to the Grassland Biome of South Africa and whether the opposite can occur, namely, an increase in plant species richness under heavy grazing. A study of a contrast between a communal area of the former Ciskei and a neighbouring nature reserve showed that intense utilization under communal use led to a significant increase in plant species richness. However, this increase was scale-dependent with the greatest significant difference occurring at sample plot scale (50 m2) but converging at the broader scale of the whole study site. Species that increased with heavy grazing included those from arid Karroid areas as well as some from more mesic grassland and savanna areas. The contribution of beta diversity to gamma diversity across the grazing contrast was relatively low which reflects the relatively high proportion of species shared between treatments. Total plant canopy cover declined sharply with heavy grazing. In terms of plant canopy cover, grazing favoured annual over perennial plants, prostrate over erect plants, and stoloniferous over tussock plant architecture. This pattern was not supported when expressed in terms of number of species belonging to these grazing response groups or traits.

Keywords

Cover Degradation Disturbance Diversity Scale 

Notes

Acknowledgements

We thank: The late Chief Nimrod N Hinana, head of the tribal authority for Amaqwati, for permission to work on the communal land; the Eastern Cape Parks Board for permission to work on the Tsolwana Nature Reserve; Johan van der Nest and Sizwe Mkhulise, former and current reserve managers respectively, for logistic assistance; Avumile Mbanjwa for help with field sampling; Jiholo Mthuthuzeli for historical information.

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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Applied Biodiversity Research Division, Kirstenbosch Research CentreSouth African National Biodiversity InstituteClaremontSouth Africa
  2. 2.Department of Botany and ZoologyStellenbosch UniversityMatielandSouth Africa

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