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The Katonga Basin covers the districts of Kabarole,
Kyenjojo, Mbarara, Mubende, Sembaule and Mpigi
and enters Lake Victoria through Nakinga Bay, Masaka
district. The major wetlands within the Katonga
catchment area are the Katonga, Nabajuzi, Kyojja and
the shores of Lake Victoria. Parts of Masaka, Mubende
Mbarara and Sembabule are generally flat with a
few flat-crested hills with long, steep flanking slopes
fluted by valleys and short pediments. The valleys are
wide and some have rivers flowing through them. The
wetlands are on the floodplains, along rivers and Lake
margins (Lake Victoria Basin Commission 2007).
The Katonga wetlands are mainly supplied by water from
surface flow from rivers, precipitation and groundwater.
The wetlands are characterized by low rainfall as it is part
of the Masaka-Ankole Dry Corridor. The main activity in
this area is livestock (cattle) farming.
Dominant plants in the Katonga wetlands include
freshwater reed species (
Cyperus papyrus
,
Loudetia
and
Miscanthus
), seasonally flooded herbaceous wetlands
where species composition is variable, seasonally flooded
wooded grassland, freshwater floating leaved but rooted
vegetation, and freshwater rooted macrophytes.
Other dominant plant species in the Katonga wetland
system are papyrus (
Cyperus papyrus
),
Loudetia
and
Miscanthus
species. These plants are tolerant to soils
that are acidic and deficient in plant nutrients. The
flood plains dominate the western catchment and are
comprised mainly of wooded grasslands with acacia
trees, which in certain instances form dense bushes.
The grasslands are dominated by
Imperata
(spear
grass),
Sporobolus
and
Hyparrhenia
species.
Sitatunga and otters are common animal species in the
Katonga wetlands. Wetland fish, in particular catfish
and lungfish, are also common. Common birds include
cranes, ducks and ibis.
Papyrus is typically used for common local crafts (for
example, baskets, trays and mats). Masaka district lies in
the coffee and banana farming area and these crops need
mulching to conserve water and soil.
Miscanthus
species
are commonly used to mulch banana plantations.
The wetlands are a major source of food, mainly fish
and game meat. They also provide water for domestic
use and for watering livestock. Wetlands play a role in
controlling floods, moderating the local climate and
trapping sediment. The wetlands along rivers stabilize
the riverbanks and lakeshores. Masaka Municipality
receives its water supply from the Nabajuzi wetland and
sewerage effluent is purified through the same system.
Only 12 km² of the wetland area in Masaka district has
been converted – mainly for crop production. Little
wetland conversion has taken place in the Katonga
wetlands system because of the low fertility and acidic
conditions of the soil.
Most of the wetlands and their surroundings come
under the mailo land tenure system – a customary form
of freehold practised in some parts of Uganda. The
extensive and heavily waterlogged wetlands are public
land, which includes the Nabajuzi, Kyogya and Katonga
wetlands. A few wetlands in the Katonga system
are partially or fully protected as part of the Forest
Reserves; these include the Kanywa, Lwamunda and
Namirembe wetlands.
The KatongaWetland System, Uganda
Papyrus plants