A guide to a vanishing flora

Date
2021-03-29
Journal Title
Journal ISSN
Volume Title
Publisher
ASSAf
Abstract
Renosterveld is a highly endangered vegetation type that once covered over 2 million hectares within the Cape Floristic Region. Today, the estimated 18 000 remaining patches are widely scattered across the landscape, collectively covering less than 4% of the original extent of this once-expansive veld type. Renosterveld differs from the neighbouring and better-known fynbos in that it occurs on nutrient-rich soils derived from shale, as opposed to the nutrient-poor sandstone soils that support fynbos. Fynbos is best known for its tall proteas and showy ericas, as well as reed-like restios. Renosterveld, on the other hand, is more grassy and characterised by shrubs of low to medium height. In the past, and unlike fynbos, renosterveld supported an abundance of large grazing mammals and their accompanying predators. This began to change around 2000 years ago when the Khoekhoen arrived with domesticated livestock whose more selective feeding habits would have differed from those of wildlife, thus impacting on the flora. Large wild mammals were virtually exterminated when European settlers arrived with modern firearms some 300 years ago, and domestic livestock became the dominant grazers. The fate of the renosterveld was finally sealed after World War II, when mechanised farming allowed large tracts of land to be converted to crops such as wheat and canola. Whether the original renosterveld was a shrubby grassland or a grassy shrubland is a topic that ecologists debate today, as the changing grazing pressures and humaninfluenced fire regimes would have affected the proportional contribution of these two important components of the vegetation. Better understanding of this issue would be important for managing this vegetation type correctly, and this book provides some insights into these intriguing questions. Nonetheless, forming an acceptably robust grasp of the functioning and dynamics of such a fractured ecosystem is akin to visualising the image of a 100-piece jigsaw puzzle from four remaining pieces.
Description
CITATION: Van Wilgen, B. W. 2021. A guide to a vanishing flora. South African Journal of Science, 117(3/4):9169, doi:10.17159/sajs.2021/9169.
The original publication is available at https://sajs.co.za
Keywords
Conservation biology -- South Africa -- Overberg, Endangered ecosystems -- South Africa -- Overberg -- Guidebooks, Ecology -- South Africa -- Overberg, Plants -- South Africa -- Overberg -- Identification, Animals -- South Africa -- Overberg -- Identification
Citation
Van Wilgen, B. W. 2021. A guide to a vanishing flora. South African Journal of Science, 117(3/4):9169, doi:10.17159/sajs.2021/9169.