A review of the effects of population pressure on watershed management practices in the Lake Victoria Basin

Abstract

Protecting the quality of soil and water while using these resources for the benefit of people is a major challenge in Uganda and indeed globally. Emphasis on agricultural sustainability arises out of increasing awareness about the finite nature of Uganda's arable land resources, the widespread problem of soil degradation, the rapidly deteriorating quality of the environment and the need to preserve soil and water resources for long-term use rather than for short term gain. The current population pressure on forests, swamps, rangelands and marginal agricultural lands leads to inappropriate farming practices, forest removal, and grazing intensities that, in extreme cases leave a barren environment that yields unwanted sediment and damaging stream flow to downstream communities. Watershed management is the process of guiding and organizing land and other resource use on a watershed to provide desired goods and services without affecting adversely the environment. The dilemma in watershed management in Uganda, and indeed globally, is that land use changes needed to promote the survival of society over long-term is at cross-purposes with what is essential to the survival of the population over a short-term. This paper reviews land management practices in the Lake Victoria basin and their impact on the environment. It addresses the current soil status; non-point pollution; timber harvesting/ deforestation; fire effects; grazing by livestock; and wetlands. Emphasis is laid on the effects of these practices on soil and water quality and the overall impact on the lake environment.

Soil Fertility in relation to Landscape Position and Land Use/Cover Types: A Case Study of the Lake Kivu Pilot Learning Site

“…In Rwanda a relative increment of 19% was observed for the same period on the expense of open broadleaved trees (eucalyptus). The relative change observed in small-scale farming area across the LK PLS is attributed to demographic pressure [44,45] and poor management of the already cultivated lands accelerating land degradation and recently observed negative effects of eucalyptus trees on soils of Bufundi [31,34] The trend in land-use/cover in the three benchmarks watershed is similar to that observed in the region [44,46,47]. Small-scale farming had significantly increased to the expenses of the other land-use/cover in the three sites.…”

“…However, in the last two decades soil fertility has been widely reported declining [28][29][30][31][32]. Supply-and demand-induced scarcities have gravely stressed the ability of food production to keep pace with population growth [33].…”

Land use/cover change patterns in highland ecosystems of Lake Bunyonyi Catchment in western Uganda

“…Lake Bunyonyi catchment is an important ecosystem, supporting agriculture and provisioning of other ecosystem services to the livelihoods in the region (Kabale and Kisoro district). However, with increased population density and growth rates (UBOS, 2012), poor land management and the type of terrain (Magunda and Majaliwa, 2002), there is increasing evidence of land use/cover changes reported due to transformation of natural vegetation into farmlands, grazing lands, human settlement and urban centres (Bolwig, 2002, Maitima et al, 2009, Majaliwa et al, 2015, Bizoza, 2015. These changes are cause of declining biodiversity (Darkoh, 2003), change in ecosystem services, catchment hydrology, local climate variation, food insecurity, and change in pollution loading into surface waters (Azanga, 2013).…”