The cooler temperatures would be a result of the shade cast by the spekboom’s branches, as well as the release of water from the plant’s stomata, a process known as evapotranspiration. Animals that could thrive in the replanted thicket include Big Five wildlife – black rhinos and elephants in particular adore this habitat. It would also be able to support greater numbers of sheep and goats than degraded land currently can, while also encouraging biodiversity in other ways, with the growth of smaller plant species that thrive in the spekboom microclimate.
For more than a decade, the South African government has covered the labour costs for the replanting of an initial 7,400ha (18,285 acres) of spekboom in national parks and on private land. Christo Marais, who oversees the initiative as chief director of Natural Resource Management Programmes at the Department of Environmental Affairs, Forestry and Fishing, estimates that a further 3,000ha (7,413 acres) has been planted through private funding. With a budget of just R120m (£6.3m; $8.2m) annually for ecological restoration, Marais hopes that private landowners, like Nel, and non-profit organisations can step in to take the lead.
To date, the goal of one million hectares of spekboom thicket is still a long way off, but there are many reasons that people like Nel are persisting. “The changes and potential benefits from restoring thicket are not only due to carbon [sequestration],” says Smart.
Thriving patches of spekboom help to prevent erosion of precious topsoil and silting up dams. Another major benefit to the planting of spekboom on degraded land is the drastic increase in the amount of carbon in the soil that comes both from its roots and leaf litter, as well as the presence of other, smaller plants that are able to grow around it.
The higher carbon content, in turn, improves water retention. Research by Anthony Mills, a soil scientist at Stellenbosch University, has estimated that one hectare of restored spekboom results in 255,000 litres (56,092 gallons) of retained water. Restoring the thicket in full, would result in more than 200 billion litres (44 billion gallons) of additional water being stored in the ground – equivalent to half the capacity of Cape Town’s largest dam.