Abstract

Sustainable management of traditional medicinal plant resources is important, not only because of their value as a potential source of new drugs, but due to reliance on traditional medicinal plants for health. The vast majority (70-80%) of people in Africa consult traditional medical practitioners (TMPs) for healthcare. With few exceptions, traditional medicinal plants are gathered from the wild. Although reliance on TMPs may decline in the long term as alternative healthcare facilities become available, increasing demand for popular herbal medicines is expected in the foreseeable future. Over the same period, certain vegetation types that were sources of supply of traditional medicines will drastically decline due to forest clearance for agriculture, afforestation of montane grasslands, uncontrolled burning and livestock grazing. Exclusion from core conservation areas adversely affects TMPs who previously gathered medicinal plants in those sites. In addition, supplies of herbal medicines to TMPs are affected by competing resource uses such as timber logging, commercial harvesting for export and extraction of pharmaceuticals, and use for building materials and fuel. This creates a growing demand for fewer resources, in some cases resulting in local disappearance of favoured and effective sources of traditional medicine and reduced species diversity.

The most vulnerable species are popular, slow growing or slow to reproduce, or species with specific habitat requirements and a limited distribution. Although in theory, sustainable use of bark, roots or whole plants used as herbal medicines is possible, the high levels of money and manpower required for intensive management of slow growing species in multiple-species systems are unlikely to be found in most African countries. The cultivation of alternative sources of supply of popular, high conservation priority species outside of core conservation areas is therefore essential. However, commercial cultivation of such species is not a simple solution and at present is unlikely to be profitable due to the slow growth rates for most tree species and low prices paid for traditional medicines. These slow growing species are a priority for ex situ conservation and strict protection in core conservation areas. By contrast, the high price paid for some species does make them potential new crop plants for agroforestry systems (e.g. Warburgia salutaris, Garcinia kola, G. afzelii, G. epunctata) or agricultural production (e.g. Siphonochilus aethiopicus). Pilot studies on these species are needed.

Priority areas for cooperative action between healthcare professionals and conservationists are rapidly urbanizing regions with a high level of endemic taxa, particularly west Africa (Guineo-Congolian region), specifically Côte d’Ivoire, Ghana, and Nigeria; east Africa (Ethiopia, Kenya, Tanzania); south-eastern Africa (South Africa, Swaziland). The most threatened vegetation types are Afro-montane forest and coastal forests of the Zanzibar-Inhambane regional mosaic.