Browsing by Author "Lwasa, James"

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    Climate trends, risks and coping strategies in smallholder farming systems in Uganda
    (Climate Risk Management, 2018) Mubiru, Drake N.; Radeny, Maren; Kyazze, Florence B.; Zziwa, Ahamada; Lwasa, James; Kinyangi, James; Mungai, Catherine
    Smallholder farmers in Uganda face a wide range of agricultural production risks. Climate change and variability present new risks and vulnerabilities. Climate related risks such as prolonged dry seasons are becoming more frequent and intense with negative impacts on agricultural livelihoods and food security. This paper examines farmers’ perceptions of climate change, climate-related risks affecting crop and livestock production, including climate-risk management and adaptation strategies. Drought, increasing disease and pest incidences, decreasing water sources, lack of pasture, bush fires, hailstorms, changes in crop flowering and fruiting times were the major climate-related risks reported. In order to cope with climate change and climate variability, farmers use a wide range of agricultural technologies and strategies. Mulching, intercropping and planting of food security crops were among the most commonly used practices. Other strategies included water harvesting (mainly for domestic consumption), other soil and water conservation technologies and on-farm diversification. Farmers often use a combination of these technologies and practices to enhance agricultural productivity. Average maximum temperatures increased across the two sites. Trends in average annual rainfall showed mixed results, where a general decline was observed in one district and a relatively stable trend in the other district. Perceived changes in climate included erratic rainfall onset and cessation (which were either early or late), poor seasonal distribution of rainfall and little rainfall. In addition, farmers reported variations in temperatures. Farmers’ perception of changing rainfall characteristics and increasing temperatures were consistent with observed historical climatic trends based on meteorological data.
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    Conservation Farming and Changing Climate: More Beneficial than Conventional Methods for Degraded Ugandan Soils
    (Sustainability, 2017) Mubiru, Drake N.; Namakula, Jalia; Lwasa, James; Otim, Godfrey A.; Kashagama, Joselyn; Nakafeero, Milly; Nanyeenya, William; Coyne, Mark S.
    The extent of land affected by degradation in Uganda ranges from 20% in relatively flat and vegetation-covered areas to 90% in the eastern and southwestern highlands. Land degradation has adversely affected smallholder agro-ecosystems including direct damage and loss of critical ecosystem services such as agricultural land/soil and biodiversity. This study evaluated the extent of bare grounds in Nakasongola, one of the districts in the Cattle Corridor of Uganda and the yield responses of maize (Zea mays) and common bean (Phaseolus vulgaris L.) to different tillage methods in the district. Bare ground was determined by a supervised multi-band satellite image classification using the Maximum Likelihood Classifier (MLC). Field trials on maize and bean grain yield responses to tillage practices used a randomized complete block design with three replications, evaluating conventional farmer practice (CFP); permanent planting basins (PPB); and rip lines, with or without fertilizer in maize and bean rotations. Bare ground coverage in the Nakasongola District was 187 km2 (11%) of the 1741 km2 of arable land due to extreme cases of soil compaction. All practices, whether conventional or the newly introduced conservation farming practices in combination with fertilizer increased bean and maize grain yields, albeit with minimal statistical significance in some cases. The newly introduced conservation farming tillage practices increased the bean grain yield relative to conventional practices by 41% in PPBs and 43% in rip lines. In maize, the newly introduced conservation farming tillage practices increased the grain yield by 78% on average, relative to conventional practices. Apparently, conservation farming tillage methods proved beneficial relative to conventional methods on degraded soils, with the short-term benefit of increasing land productivity leading to better harvests and food security.
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    Distribution of Acacia senegal (L.) Willd. (Fabaceae) in Uganda and its relationship to climatic factors
    (Blackwell Publishing Ltd, 2011) Mulumba, John Wasswa; Lwasa, James; Atieno, Frederick
    The aim of the study was to map the distribution of Acacia senegal and its infraspecific taxa in Uganda and predict its suitable range of occurrence based on climatic factors. The distribution of the infraspecific taxa was analysed for richness, diversity, turnover and reserve selection. Regression analysis was performed to understand the relationship between distribution of the species and climatic variables. Georeferenced species occurrence points were superimposed over temperature and vapour maps. Areas with highest taxa richness, diversity and turnover were mapped and found in the Lake Kyoga basin. The species shows preference for the northern region of the study area with dissimilar climatic pattern from the southern region and the superimposition supported findings. Variety kerensis exhibited narrower climatic, altitudinal and distribution range preference. Temperature seasonality, maximum temperature of warmest month, temperature annual range, mean temperatures of warmest and driest quarters had the highest coefficients of determination (r2 > 0.7) hence most important in influencing species distribution. The most appropriate locations for in situ conservation and for germplasm collection to ensure maximum diversity is secured are found in Wabisi-Wajala, Kiula, Kyalubanga, Bajo, Kasagala, Kabwika-mujwalanganda, Maruzi, Moroto and Napak Central Forest Reserves. The study recommends ecological studies to understand status of A. senegal.