The Uganda Atlas

Soils: Changes Classification and Nomenclature .

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

NEMA 2005

Vertisols

19,066

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)

Table 4: Soil Types and Productivity status in Uganda

Changes

Classification and Nomenclature

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).

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.

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