Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4520645 | South African Journal of Botany | 2014 | 11 Pages |
•Vegetation survey and subsequent ordination revealed significant differences within the study area.•Despite this, soil chemistry was by and large uniform across the study area.•The seedbank was dominated by alien species.•Burning had no significant effect on seedbank.•Active restoration is required for large swathes of the study area.
Peninsula Shale Renosterveld is a poorly understood and critically threatened vegetation type. Less than 13% of its original extent remains and the surviving fragments are restricted to the area surrounding the Cape Town city bowl. A substantial portion of Peninsula Shale Renosterveld is situated in the Groote Schuur Estate, currently conserved within the Table Mountain National Park. Due to a history of diverse land-use impacts what remains today is a complex mosaic of alien invasive species and indigenous vegetation in various states of degradation and to improve the conservation value restoration is required. However, it is imperative that prior to restoration initiation data is collected from the site. To enhance the understanding of the ecosystem drivers of Peninsula Shale Renosterveld with a view to evaluate restoration potential and inform future restoration initiatives a detailed analysis of four typical vegetation states found within the study area was undertaken. This was accomplished through a vegetation survey investigating different ‘states’ of the contemporary condition of the study area and an examination of the health of the seedbank through a burning and greenhouse experiment to ascertain whether it could prove a useful asset in future restoration initiatives. The results show how historical drivers have created a novel ecosystem with vegetation states ranging from relatively healthy Renosterveld vegetation, indigenous vegetation requiring intervention to maintain its integrity, and regions of the study area which are dominated by alien grasses and Pinus plantations. The seedbank diversity was found to be poor, dominated by alien ephemeral species and unlikely to assist in restoration efforts. Although certain areas may retain their ecological integrity through passive restoration, large swathes of the study area require active restoration to return the degraded vegetation to functional Peninsula Shale Renosterveld.