The Uganda Atlas

Rakai District Local Administration (2007)

Kooki hills in Kibaale-Bukoora, Rakai District

The degraded hills of Kooki in Rakai District

The most common morphology of the hills comprise of round to flat summits that abruptly descend on steep convex and straight slopes, ending in relatively gentle and moderately concave pediments. The pediment slopes show an abrupt steepening in their lower sections adjacent to valley floors which are often swampy. Gemorphologically, Kooki hills are thought to result from an upwarped Buganda plateau during early Tertiary, after a long quiescence from the Karoo era and subsequent reduction of the plateau landscape by denudation process to a very low relief, the African Surface in this Buganda part of Uganda which, therefore, is sometimes called Buganda surface. The uplift resulted in an elevated and dissected plateau consisting of a series of flat-topped hills or their remnants and intervening valleys. Thus, the landscape was dissected by the rejuvenated drainage system, leading to a dissected plateau in form of the present ridges and hills. In some cases, the Kooki hills are related to the Kigezi-Ankole surfaces (highlands), but generally, Rakai hills are regarded as an upwarping of the Buganda surface.

The soils in the Kooki area are dominantly of Ferralsols type and its associations. This is the most dominant soil type in Uganda, covering about 2/3 of the country. This is a class of soils considered to be the oldest on earth; the soils are characterized by low fertility levels and are deeply weathered and leached with little mineral reserves remaining. Generally, soil distribution varies with slope morphology, in that at the summits, moderately deep to shallow soils often occur; but on the steep convex and straight slopes, soils become very thin with depths varying from bare rocky or weathered regolith surfaces to only a few centimeters deep. Further down on the concave and pediment slopes, respectively, soil depths increase appreciably often reaching depths of over 150 cm. On the hill summits and steep upper and middle slopes, the soils are Plinthic Ferralsols and Hyperskeletic Leptosols. These associations are dominantly shallow, loose and skeleteral, with high proneness to erosion. Most of the former summit laterite capping has been removed leaving behind disintegrating boulders and relics

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