Growing plants used in traditional medicines could rescue Africa's driest regions from total soil degradation and provide much-needed income and healthcare for the rural poor, said the World Bank in a report published last week (27 October).
It says the global market for traditional medicines and the plants they are derived from is worth about US$65 billion, partly because of demand for plants used as raw materials in Western medicines.
Being able to capture even one per cent of this — US$650 million — would mean a significant injection of cash for Africa's arid regions, says Warren Evans, the World Bank's director of environment.
Millions of people in sub-Saharan Africa struggle to make a living from arid land that not only gets little rain but also has been damaged by overgrazing, deforestation and poor irrigation practices.
According to the report, growing medicinal plants "can help check runoff and erosion, control flooding, purify water, and protect against wind".
The report identifies 38 plants that could grow in dry conditions. One is a type of acacia tree that is the source of 'gum arabic', used to treat inflammation of the throat and stomach. Sudan's dry savannas are a major source of the gum, whose global market is worth US$90 million.
Another of the plants, known as devil's claw, is grown in the arid grasslands of southwest Africa. It has anti-inflammatory properties and is used to treat arthritis.
The report stresses the need for growing indigenous plants. Although non-native plants might hold more commercial promise, it says, they could threaten the local biodiversity.
Regenerating dry areas will depend on community involvement, says the report. Local people can help establish and run nurseries to produce seedlings, and can take responsibility for maintaining newly planted areas.
It cites the example of Burkina Faso, where a community-based project to regenerate thousands of hectares of degraded land helped boost cereal yields and livestock production, and halved the number living in poverty.