The Significance and Sustainability of Charcoal Production in the ...

soils are the main soil types in Dakatcha Woodland area (Teel 1988: 21). Figure 4 depicts the
dominant soils in Dakatcha Woodland area according to FAO 90 classification: Vertisols,
Solonetz, Arenosols, Ferralsols, and in minor extent Fluvisols, Planosols and Luvisols. The
soils in the Coastal Plain and Foot Plateau have developed on coastal sands and coral
limestone; in the previous the soils vary in depth and structure, but are generally well-drained
having moderate to low fertility where as on the latter they are deep and well-drained (Foeken
2003: 30).
Arenosols and Ferralsols of low fertility present various degrees of limitations, such as low
plant nutrient content, low nutrient retention capacity, moderate soil moisture retention and
high toxic exchangeable aluminium content, when forests on those soils are cleared for arable
farming (Kauffman et al. 1991: 9). The previous have the least favorable properties for
agriculture (ibid. 17-18), being part of the sandy soils according to IPCC classification (Batjes
2010: 4-5). They are associated with semi-arid areas that have shrub vegetation cover with
isolated larger trees (Spaargaren & Deckers 1998: 26). Ferralsols are characterized by
dominance of low activity clays, but favourable physical properties of well-drained upland
Ferralsols ensure that these soils are easy to work and hardly prone to erosion (ibid. 21, 23-
24). Vertisols, Solonetz, Luvisols, Planosols and Fluvisols are all high activity soils (Batjes
2010: 4-5). The last two occupy poorly drained positions and are present on materials
deposited in aqueous sedimentary environments, in Dakatcha Woodland near the River
Sabaki (Spaargaren & Deckers 1998: 21, 26). Luvisols have the most favourable properties for
agriculture in Dakatcha Woodland (Kauffman et al. 1991: 17-18).
3.1.3 Climate
Annual rainfall in Dakatcha Woodland as elsewhere in Kenya depends on the Inter-Tropical
Convergence Zone (ITCZ) that takes place as a result of the overhead sun during the season.
The rainfall is relatively low because the predominant seasonal winds have a track parallel to
the coast and have already passed over large areas of land before reaching Kenya (BBC 2011;
Kenya Meteorological Department 2011: 2). The coastal region is characterised by a high
degree of rainfall variability between years, between the same months in different years, and
between places (Foeken 2003: 32). For instance, the rainfall witnessed in Malindi area during
the short rains in 2010 was only 31.9 percent of average, which led into food shortages and
water scarcity (Kenya Meteorological Department 2011: 5).
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