The Kuzuko Thicket Restoration Project (KTRP) is planning to plant spekboom (Portulacaria afra) cuttings over 5,000 hectares in the Eastern Cape, South Africa. Over a period of fifty years, the planted spekboom will sequester carbon and increase biodiversity, thereby providing a number of related benefits. To know how much carbon has been sequestered and by how much biodiversity has increased due to the KTRP’s activities, it’s important to know baseline values of carbon stock and biodiversity. In November 2014, C4 undertook an assessment to determine these values.
Figure 1. Spekboom cuttings will be planted in degraded habitat. Once the spekboom cuttings have matured, bare patches like this will no longer be visible.
Careful planning and hard work are required to collect reliable data. To prevent bias we randomly selected sampling locations across the KTRP area. In each sampling location, we applied consistent and thorough methods to estimate the amount of carbon contained in the soil, living trees and dead organic matter. We also counted the number of different plant species and measured their coverage in each sample location as indicators of biodiversity. These sample data will later be extrapolated to estimate carbon stock and biodiversity across the total KTRP area.
Figure 2. A digital calliper is used to measure the basal stem diameter of a spekboom plant. This data will be used to calculate carbon stocks in the Kuzuko Thicket Restoration Project area.
Figure 3. Evidence of a spekboom cutting developing lateral roots. The specimen in this picture was only planted two weeks prior
True to any fieldwork that generates useful data, we engaged in a number of activities that weren’t specified in official sampling methodology. These included, but were not restricted to: avoiding scorpions and snakes; crossing flooded rivers; freeing vehicles from muddy culverts; and crawling through impenetrable spekboom armed with nothing but callipers. Over time, the KTRP will require further data collection and this will no doubt require similarly challenging adventures – something we always look forward to at C4.
Figure 4. Collecting botanical data from mature spekboom plants is a challenge, but necessary to quantify the outcomes of the project activities.