FORMATION AND DISTRIBUTION OF THE VALLEY SIDE GULLIES IN CENTRAL UGANDA

The dry subhumid area of Central Uganda forms part of the ‘cattle dry corridor’ characterized by relatively low but unpredictable rains, poor resource development, high livestock population and increasing human population densities leading to environmental degradation problems including gully erosion. This paper examines the characteristics of gullies and the main intrinsic and extrinsic variables affecting their spatial distribution in the central drylands of Uganda. A field survey was used. Preliminary studies were done covering two sub counties in the district of Nakasongola, and then more detailed studies narrowed to 2 sub catchments close to Migera town. Ten gullies were sampled for detailed measurements. The spatial distribution of all gully scars were identified in the field and their positions recorded using a Global Position System. This data was imported in Geographical Information System in ILWIS 3.2 environment. Field measurement of gully dimensions (lengths, width and depth) was done and the data used for computing the volume of soil loss from gully erosion. Results revealed that in general land degradation by gullies in this dry sub humid area is an increasing problem, which is mainly attributed to human activities of livestock grazing and movement. The extent and magnitude of erosion by gullies, however, is controlled by soil characteristics and topographic variations. The gullies were largely discontinuous, dominantly of linear pattern and rarely exceeded 2 m depth. There is urgent need to address the problem of degradation by gullies, while taking into consideration the controlling factors, in order to ensure sustainable rangeland management

Horticulture in Mountain Agro-Ecosystems of Uganda: Environmental and Socio-Economic Threats and Opportunities

Horticultural crops have gained importance over the recent years as a strategy for addressing livelihood improvement particularly amongst both the rural and urban poor in high- and low- mountain areas. Mountain ecosystems in Uganda, however, are under pressure driven by increasing population, urbanisation and globalization.  This has resulted into widely reported environmental degradation. Environmental and social concerns are a reality that needs to be underpinned if sustainable use of these ecosystems is to be achieved. This paper examined the socio-ecological problems, challenges posed by increased shift to horticultural farming and opportunities in mountain ecosystems of Uganda, using a case study of Mt Elgon. Data collection was obtained largely through household surveys, focus group discussions and field observations. Results revealed that household economic gain and unsustainable traditional crop production systems were the main drivers for the recent shift to intensive horticultural system. These changes have caused environmental and social concerns particularly accelerated erosion, health risks associated with increased use of chemical inputs, and conflict largely attributed to encroachment on conservation areas for farming and staking materials.  The study recommends for pro-active measures (e.g. increased investment in horticultural value chain) in mitigating environmental and social problems if future sustainability of the mountain ecosystems are to be attained