This has important consequences for the land degradation process for a number of reasons. As an example, our preliminary findings show that significant amounts of carbon stored in the soil are lost after grasslands have been converted to bushland. It takes decades before bushes can sequester – or store – more carbon in the soil again. In addition, bush encroachment is thirsty: the bushland roots reach much deeper into the soil than grasslands, sucking up valuable water resources, which in turn makes less water available for grasses and changes the local ecology.

While bushes are a natural feature of Otjozondjupa Region, it is not clear what is causing the rapid increase in bush density, and as yet, no cost-effective method has been identified to stop the encroachment. Some evidence suggests that livestock herding may itself be a driver, since bushes may be replacing grasses that have been overgrazed.