+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Dynamics of woody vegetation in a semi-arid savanna, with a focus on bush encroachment



Dynamics of woody vegetation in a semi-arid savanna, with a focus on bush encroachment



African Journal of Range and Forage Science 24(3): 131-140



Increases in the tree:grass ratio with accompanying changes in herbaceous composition, called bush or shrub encroachment, is a worldwide phenomenon in savanna regions. Although heavy grazing by livestock is often believed to be the cause, it is clear that the factors and processes involved in bush encroachment are poorly understood. The effects of soil type and grazing on the tree:grass ratio in encroached Acacia mellifera-dominated savannas in the Northern Cape, South Africa, were investigated by means of vegetation classification and analyses of sequential aerial photographs. Acacia mellifera never occurred on clay pans, and in low numbers only in other clay and sandy soils. This trend is ascribed to the soil texture, soil water regimes and/or heavy utilisation in these areas. Soil rockiness was important in determining the long-term presence and abundance of A. mellifera, perhaps due to better soil moisture conditions. Long-term increases in A. mellifera in non-rocky habitats were also found, although the causes of this remain unclear. Grazing strategy did not prove to be important in determining presence or abundance of A. mellifera in the short- or long-term.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 020900130

Download citation: RISBibTeXText

DOI: 10.2989/ajrfs.2007.24.3.3.296


Related references

A patch-dynamics approach to savanna dynamics and woody plant encroachment - insights from an arid savanna. Perspectives in Plant Ecology, Evolution and Systematics 7(4): 229-242, 2006

Overgrazing and bush encroachment by Tarchonanthus camphoratus in a semi-arid savanna. African Journal Of Ecology: 3, 449-451, 2008

Biomass increases go under cover: Woody vegetation dynamics in a communally utilised semi-arid savanna in Bushbuckridge, South Africa. South African Journal of Botany 98: 191-192, 2015

Composition and structure of woody vegetation in a semi-arid savanna with particular reference to browsing. Minor Field Studies International Office, Swedish University of Agricultural Sciences ( 98): 35 pp., 2000

Woody vegetation-environment relations in a semi-arid savanna in the northern Transvaal. South African Journal of Botany 58(4): 268-274, 1992

The significance of the woody component of semi-arid savanna vegetation in relation to meat production. Proceedings of the Grassland Society of Southern Africa 12: 105-108, 1977

Rainfall, land use and woody vegetation cover change in semi-arid Australian savanna. Journal of Ecology Oxford 93(3): 596-606, 2005

Woody Vegetation Spatial Patterns in a Semi-Arid Savanna of Burkina Faso, West Africa. Plant Ecology 132(2): 211-227, 1997

Effect of woody vegetation clearing on nutrient and carbon relations of semi-arid dystrophic savanna. Plant and Soil 331(1-2): 79-90, 2010

Woody vegetation spatial patterns in a semi-arid savanna of Burkina Faso, West Africa. Plant Ecology 132(2): 221-227, 1997

Spatial patterns and dynamics of woody vegetation in an arid savanna. Journal of Vegetation Science 2(4): 565-572, 1991

Effects of repeated burning on woody vegetation structure and composition in a semi-arid southern African savanna. 2013

Herbaceous vegetation response to grazing exclusion in patches and inter-patches in semi-arid pasture and woody encroachment. Agriculture, Ecosystems & Environment 179: 125-132, 2013

Simplification of the composition, diversity and structure of woody vegetation in a semi-arid African savanna reserve following the re-introduction of elephants. Biological Conservation 180: 122-133, 2014

Long-Term Impacts of Goat Browsing on Bush-Clump Dynamics in a Semi-Arid Subtropical Savanna. Plant Ecology 183(2): 277-290, 2006