The effect of ploughing and augmenting natural vegetation with commercial fynbos species on the biodiversity of Overberg Sandstone fynbos on the Agulhas Plain, South Africa

In an attempt to reconcile wildflower cultivation with plant diversity conservation, we investigate the effect that different augmentation techniques (including ploughing and burning) have on the plant diversity of the Fynbos Biome. We evaluated the effects of two ploughing intensities followed by augmentation at one site, and augmentation without ploughing at another on the plant diversity in Overberg Sandstone fynbos on the Agulhas Plain, South Africa. Results showed that plant diversity was the highest in areas which were either shallow-ploughed and augmented or augmented only; thus these treatments appear not to have a significant negative effect on plant diversity at least in the short-term. Deep ploughing, however, was detrimental to plant diversity. Results could be explained by the intermediate disturbance hypothesis i.e. intermediate levels of disturbance prevent the competitive exclusion of subdominant species. The conclusion drawn from this study is that low-intensity cultivation of commercial fynbos species can be diversity-friendly, but high-intensity disturbance practices should be avoided. (C) 2009 SAAB. Published by Elsevier B.V. All rights reserved.