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study, Fairhead, Leach, and colleagues are now uncovering a fascinating story of sustainable
farming methods in west and central Africa, which closely parallels the soil technologies
found in the Amazon. Kissidougou prefecture, in the upper catchment of the Niger river, com-
prises a landscape mosaic of dense, semi-deciduous rainforest patches and open expanses of
grassy savanna. The forest islands are generally circular and about 1 to 2 km in diameter, and
are home to approximately 800 villages. Since French occupation in 1893, Guinea's adminis-
trators were convinced that these forest patches were the last relics of a dense, humid forest
that once covered the landscape. They assumed that villagers had progressively converted the
forest into savanna, through shifting cultivation and fire setting, preserving only narrow belts
around villages. One hundred years later, this same assumption persisted in the European
Union (EU)-funded
Programme d'Aménagement des Bassin Versantes de l'Haute Niger
;
humans were assumed to be agents of degradation, and local inhabitants were presented as
incompetent resource stewards (Leach and Fairhead 2000).
Based on historical sources, ethnographic interviews and satellite images, Fairhead and
Leach (1996) showed that the forest islands are not the relics of a destroyed forest, but are in
fact grown on savanna land by Kuranko and Kissi farmers for subsistence, social, and ritual
reasons (see Chapter 4) (Fairhead and Leach 1996a, b, Leach and Fairhead 2000). Further-
more, a time-series of aerial photographs and satellite images of five major villages shows
that forest areas increased in all locations between 1952 and 1992, again running counter to
the deforestation and degradation narrative. Fairhead and Leach's work led to a complete
reinterpretation of the landscape and a much better recognition of people's ability to effect-
ively manage and conserve natural resources.
The humid tropics of west and central Africa have similar soils to those in Amazonia, being
highly weathered and leached, with low nutrient content. Multidisciplinary studies are now
revealing that the forest islands are thriving on enriched anthropogenic dark earths, analo-
gous to the
terra preta
of Amazonia. Forest islands are common in the forest-transition zones
of Guinea, Liberia, Sierra Leone, and Ghana; in Liberia alone, a regional survey of four coun-
ties has confirmed African anthropogenic dark earths at 134 locations (Fairhead and Leach
2009). There may be more dark earths in the densely forested areas, which are less well stud-
ied than the savanna transition zones.
As was found in the Amazon, these African dark earths are anthropogenically enriched soils
and are an integral part of farming and the socioecological systems of the regions (Frausin
et al. 2014). Soil fertility is enhanced and stabilized by the incorporation of organic matter like
charred wood, food waste, rice straw, old thatch, the by-products of processing oil palms, and
human excreta and animal manure. These materials are piled up over a period of years, then
charred and incorporated into soils as biochar. As soils become richer, they are used as
homegardens, where crops like sweet potato, onions, okra, cassava, and aubergines are grown
mainly for subsistence use (Frausin et al. 2014). Over time, these homegardens are supplanted
by agroforestry tree crops such as cocoa and oil palm, kola (
Cola nitida
), valued for social and
ritual purposes, and silk cotton trees (
Terminalia superba
). These are high value products that
bring in cash income, important for paying school fees and for purchasing products like live-
stock and building materials (Frausin et al. 2014). Access to forest islands depends on social
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