OVERVIEW OF THE IMPACT OF MINING ON THE ... - IIED pubs

3.28 The Ume sub-catchment
3.28.1 General description
3.28.1.1 Hydrology
This is Zone Z5 of Area A (ZSG, 1984). The sub-catchment comprises the valley of the Ume River and its
tributary, the Sessami (Figure 3.2). Neither is perennial.
3.28.1.2 Geology
See Figure 3.6 (ZGS, 1999). The geology consists mainly of Karoo Supergroup sediments, capped on the
Mafungabusi (Mapfungautse) Plateau by Karoo basalt, Gokwe Formation sediments and Kalahari Sands. The
Matuzviadonha (Matusadona) Mountains are formed of a crystalline inlier.
3.28.1.3 Pedology, agriculture and land use
Soils in the sub-catchment can be divided into four groups:
• Moderately deep sandy soils derived from Karoo sediments (most of the sub-catchment);
• Very shallow, gravelly soils derived from the crystalline inliers; and
• Moderately deep kaolinitic sandy to loamy sand soils derived from Karoo basalts on the Mafungabusi
Plateau (DRSS, 1979).
The sub-catchment lies in three Natural Regions: Region V in the Zambezi Valley: low and erratic rainfall: below
650mm; Region IV in the middle Sengwa Valley: fairly low rainfall of 450mm to 650mm per annum; Region III on
the Mafungabusi Plateau and in the Rutope valley: higher rainfall and deeper soils (ZSG, 1997; Surveyor
General and AGRITEX, 1998).
Land use comprises the Omay and Gokwe Communal Lands and Parks & Wildlife Land and Forestry
Commission Land45 (ZSG, 1998). Such farming as takes place in the north is limited to livestock production
(especially goats) and a few drought resistant crops, with more croppage in the Gokwe Communal Land. The
Zambezi Valley is sparsely populated, but the Sessami Valley is more densely settled. The largest settlements
are Gokwe Town, and Bumi Hills and Siakobvu Villages.
45 Matusadona National Park and Mafungabusi Forest Land
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