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Biology Articles » Biodiversity » Biodiversity in Africa » Environmental goods

Environmental goods
- Biodiversity in Africa

Many important food crops originate in Africa, including several species of millet and sorghum, one species of rice, the grain crop teff, and the oil palm. Globally, about 7,000 of the 270,000 known plant species have been used as food (FAO 1997), but only about 200 have been domesticated, and just 20 of these are of major economic importance. About two-thirds of the overall calorie intake is provided by ten crops. Globally, only 30-40 species (0.25 percent of 15,000 species of mammals and birds) have been used extensively in livestock production, and fewer than 14 account for over 90 percent of livestock production. African biodiversity is closely linked to nutrition and achieving food security. Nearly three-quarters of the recorded protein consumption in Africa is derived from plant sources. In rural areas, essential micronutrients are derived from eating a large variety of plant foods. Foods from the wild are particularly important in times of stress – drought, illhealth and economic change – and, as discussed in Genetically modified crops in Africa, shifts to monoculture may present threats to biodiversity, human health and food security. Much of the animal protein consumed is either directly harvested from wild populations (fisheries and bushmeat), or produced through grazing of natural ecosystems by domestic livestock. Freshwater fish is a key source of protein. For example, in hyper-arid Mali, fish makes up 60 percent of the total animal protein consumed annually. In Central and Western Africa, bushmeat (wild animals and birds) is a major source of animal protein, making up more than 80 percent of consumption in some areas. Milk, often in sour form, is also an important protein source.

Freshwater fisheries, such as those at lakes Victoria, Tanganyika and Malawi, support subsistence livelihoods and enterprises at multiple levels. Wetland systems, including those of Lake Banguelu, the Kafue floodplain and the Okavango delta, are also important sources of food. Important commercial marine fisheries are located off the west coast of Southern Africa (South Africa, Namibia and Angola), the Horn of Africa, and off the coast of Mauritania in Western Africa; collectively these provide about half of the total catch. These fisheries are centred on commercially important species such as hake, anchovy and pilchard, and the associated industries are an important source of employment.

Forests and woodlands provide a wide range of environmental goods. Over 80 percent of people rely on wood or charcoal for domestic cooking and heating, as processed fossil fuels are too expensive. Charcoal tends to be preferred in most urban areas, as the energy content per unit mass is about double that of wood. Charcoal is also cleaner-burning at the point of consumption than wood, so that the health impacts of charcoal are about four times lower than that of wood, but the total greenhouse gas (GHG) emissions (including the making of the charcoal using earth kilns which are not efficient) are higher. Forests and woodlands also provide poles, bark string and thatch for houses and livestock pens. Especially in rural areas with only a partial cash economy, natural ecosystems are the main source of building material, which would be unaffordable if it had to be purchased. Several forest and woodland species are important as commercially traded timber, especially for the furniture industry. These include species such as Pterocarpus angolensis and Melia. Most of these species are harvested from natural ecosystems, although some are now being established as plantations.

Natural ecosystems provide a wide variety of plants and animals that are important for traditional medicines and modern pharmaceutical products. Up to 80 percent of people make some use of traditional medicine, which draws on a wide variety of indigenous plants and animals, and especially on rare or unusual organisms. Important modern pharmaceutical products are derived from certain plants. For example, the Namibian devil’s claw (Harpagophytum procumbens) is used locally for digestive problems, arthritis and low back pain, and supports lucrative trade. The bark of the afromontane tree Prunus africana is the source of a commercial prostrate remedy.

Pharmaceutical bioprospecting is likely to increase in coming years, especially as new methods that utilize evolutionary and ecological knowledge enhance productivity. The 2004 global market for herbal medicines, including herbal products and raw materials, was estimated to be US$65,000 million. As a source of income, medicinal plants compare favourably with coffee, oil palm, cocoa and cotton, and they do not appear to be affected by the Organisation for Economic Cooperation and Development’s (OECD) market and trade barriers which affect other commodities from developing countries. Rural communities have a great opportunity to effectively use their local knowledge to become serious players in the global herbal medicine market.

Many plants and animals originating in Africa are important commercial trade products. Coffee (Coffea arabica and Coffea robusta) originates in Ethiopia and ranks among the five most valuable agricultural exports from developing nations, employing about 25 million people worldwide. Aspalathus linearis (Rooibos tea), originating from South Africa, is now traded globally in the fast-growing speciality tea industry. The world’s ornamental flower market includes a substantial number of species derived from Africa: Gladiolus, Pelargonium, Geranium, Strelitzia, Viola, Protea, Kniphofia and Zantedescia. The growing international pet trade includes several African species, including many endemic cichlid fish species from Africa’s rift valley lakes for aquariums. Key trade-related concerns include: the illegal (and often wasteful) harvesting from wild populations of often rare species; the accrual of benefits to individuals, whereas the costs are borne by society as a whole; and international intellectual property rights and patent agreements which can deprive local people of benefits. Currently, relatively little of the value derived from species originating in Africa accrues to Africa. Ensuring that such benefits are captured in future represents a major opportunity for expanding biodiversity-based development.


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