Alexander Stuart Hall

Background

I completed a BSc undergraduate degree in Ecology at the University of Cape Town in 2009, and did an Honours degree in Botany in 2010. For my Honours degree I did two projects, one looking at systematics of the Mulanje Cedar Widdringtonia whytei, a narrow-range endemic from Malawi. My other project looked at long-term vegetation change within the Cape of Good Hope Nature Reserve surveying long-term monitoring plots which were established during the 1960s. In 2011 I conducted a study on Rondebosch Common in Cape Town looking at the effect of fire and subsequent alien invasion on the indigenous biodiversity. During 2012 I worked as an intern at Stellenbosch University on plant-animal interactions, investigating pollination success of a few reintroduced plant species at Tokai Park following alien clearing. I started my MSc in Conservation Ecology at the beginning of 2013.

Current research

For my MSc I am looking at the potential for restoration of Cape Flats Sand Fynbos at Blaauwberg Nature Reserve following clearing of Acacia saligna. The Fynbos vegetation of the Cape Lowlands has been highly impacted by agriculture and urban development, and alien plants have invaded most of the remaining natural habitats. It is crucial to restore areas degraded by alien infestation in order to improve the conservation value of remaining natural areas. Blaauwberg Nature Reserve falls within Cape Flats Sand Fynbos, which contains a high number of endemic as well as threatened species. Part of the site was cleared by volunteers over a few years and the Fynbos did recover there, albeit lacking in certain structural components. However, density and duration of invasion have been shown to be very important in determining the ability of Fynbos to recover following clearing. Invasive species alter aspects of the ecosystem including soil chemistry and fire regime, until a threshold is passed after which Fynbos will not recover following clearing. Complex management interventions may then be necessary in order to restore the ecosystem. The first aim of my study is to investigate whether certain clearing and burning treatments will lead to more successful Fynbos recovery than others under different degrees of alien impact. The second aim is to assess the point beyond which ecological thresholds have been passed, whereby Fynbos will not re-establish due to depleted indigenous seed bank or altered soil chemistry. It will be determined whether active restoration intervention involving sowing seed of species representing certain Fynbos elements will help to restore the ecosystem in such cases.