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Changes
Over the years, food production has been characterized
by subsistence farming. A subsistence production
system usually focuses on maximizing short term profit
which promotes consuming and depleting natural stocks
of plant nutrients. Such a farming system has resulted
in soil fertility degradation through nutrient mining.
In the past, when Uganda’s population was still low,
lost soil fertility was restored through long periods of
fallows. With an average land holding of about 2 ha
per household today, fallows are no longer practical.
Research has demonstrated that fertilizer inputs and
appropriate land management practices are important
components of technology required to maintain or
improve soil fertility in Uganda (P. Ndeki et al).
Classification and Nomenclature
The major criteria in soil classification are the physical
and chemical characteristics. Physical characteristics
include factors such as parent rock, texture, structure,
location, depth, colour, and topography, while chemical
characteristics include pH, base composition, base
saturation, and Cation Exchange Capacity (CEC). Going by
those criteria, 13 major classes (some with sub classes)
have been identified at national level (see Table 4).
The earlier nomenclature of soils in Uganda was based on
the catena system, in which units were assigned names of
the most prominent town or centre in the area. This Atlas
however uses reclassified soils based on the standard FAO
nomenclature.
The high productivity soils cover only 8% of the area of
Uganda. This is indeed a small area. Therefore, moderate
and fair productivity categories form the bulk of the
soils and must be effectively managed in order to sustain
Uganda’s agriculture. Furthermore, through intensive
but sustainable agricultural practices, yields on low
productivity soils can be enhanced.
Table 4: Soil Types and Productivity status in Uganda
Severe soil erosion on Mt. Elgon slopes in Kapchorwa District, resulting from
loss of vegetation cover and leading to heavy siltation of River Ngenge (2005)
Soils Types
Soil Type
Sub Type
Area (Km
2
)
Andosols
Leptic/Skeletic
5,751
Melanic
63
Arenosols
5,579
Calcisols
204
Ferralsols
Acric
43,180
Lixic
24,392
Gleysols
24,019
Histosols
580
Leptosols
22,086
Luvisols
5,275
Nitisols
3,907
Planosols
1,735
Plinthosols
Petric
35,205
Regosols
Dystric
5,072
Eutric
8,085
Vertisols
19,066
45
Soils:
Changes
Classification and Nomenclature
.
NEMA 2005