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Dynamics of shrub encroachment in an African savanna: relative influences of fire, herbivory, rainfall and density dependence
Summary 1 Shrub encroachment has been widely observed in savanna regions. This study analysed the causes of shrub encroachment in the lowveld savanna of north-eastern Swaziland, southern Africa,
The dynamics of arid and semiarid grazing systems are prone to the effects of highly variable rainfall, with droughts causing frequent episodic mortality in herbivore populations. This has led to the
Systematic land-cover change in KwaZulu-Natal, South Africa: Implications for biodiversity.
Land-cover change and habitat loss are widely recognised as the major drivers of biodiversity loss in the world. Land-cover maps derived from satellite imagery provide useful tools for monitoring
Influence of precipitation and species composition on phytomass of a semi‐arid African grassland
1  The influence of botanical composition on annual phytomass production of a semi‐arid grassland in response to precipitation was tested with a 19‐year experiment. Three compositional states
Effect of stocking rate and rainfall on rangeland dynamics and cattle performance in a semi‐arid savanna, South Africa
Key implications for management are the inequality of different parts of the landscape in supporting livestock and in their sensitivity to grazing, slopes being more easily degraded than bottomland; and the pronounced changes that grazing can induce in semi-arid savanna during and subsequent to drought years.
Acacia karroo invasion of grassland: environmental and biotic effects influencing seedling emergence and establishment
A. karroo seedlings are capable of establishing and surviving within a dense grass sward for at least a year, tolerant of low irradiance and of interference, which, because most seeds do not persist for much longer than ayear, suggests this species forms predominantly a seedling bank.
Composition and population responses of an African savanna grassland to rainfall and grazing
Species abundance, plant basal area, and mortality were likewise more strongly influenced by rainfall variability than by grazing, and differences in the population dynamics of species were related to their life history attributes.
Bush encroachment in southern Africa: changes and causes
Bush encroachment has been recognised in southern Africa since the late nineteenth century. Our review of 23 studies showed that the rate of woody cover change has ranged from −0.131 to 1.275% y−1.
Influence of land use on plant community composition and diversity in Highland Sourveld grassland in the southern Drakensberg, South Africa.
Summary 1 Biodiversity conservation of grasslands in the face of transformation and global climate change will depend mainly on rangelands because of insufficient conservation areas in regions
Resource heterogeneity and ungulate population dynamics
It has been suggested that climatic variation has the effect on the dynamics of arid and semi-arid grazing systems of reducing animal numbers below the level at which they have much impact on