Journal Articles

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Assessment of hydro-pedological characteristics at medium-sized landslide sites in Manafwa catchment, Mount Elgon, Uganda
(Hydrological Sciences Journal, 2024-05-17) Moses, Kutosi; Yazidhi, Bamutaze; Bob, R. Nakileza; Yeeko, Kisira; Geofrey, Gabiri
Though strongly linked to landslides, hydro-pedological characteristics are inadequately investigated in the area. This study investigated hydro-pedological characteristics at medium landslide sites in Manafwa catchment. The design had twelve (12) infiltration experiments that were conducted at each site. To determine the selected soil physical properties, composite soil samples were extracted from the infiltration sites for soil laboratory analysis. Soil cores were extracted to determine saturated hydraulic conductivity (Ksat) and bulk density. The observed high values of IR and rapid Ksat underscore the susceptibility of the studied sites to landslide hazards. Additionally, soil organic matter (SOM), clay content, and bulk density further contribute to the understanding of the hydro-pedological factors influencing landslide occurrences. These findings reveal the need for comprehensive investigations into hydro-pedological characteristics of other landslide categories to assist in landslide risk assessment and management strategies.
Modelling the impact of land use/cover changes on water balance of a humid equatorial highland catchment in Southwestern Uganda, East Africa
(African Geographical Review, 2022-11) Loy, Turyabanawe Gumisiriza; Geofrey, Gabiri; Bernard, Barasa; Geoffrey, Mukisa; Claire, Nabatta
This study investigates impact of land use/cover change on water balance of River Mitano catchment in Southwestern Uganda using SWAT model. Land use/cover changes were assessed using three land use maps for years of 2000, 2010 and 2020. Water fluxes were simulated using observed daily discharge.14.4% of precipitation received is converted into discharge, with base flow (2.9%) and lateral flow (11.8%) major contributors. Conversion of grasslands to cropland and built-up areas were key changes. An increase in cropland (6.8%) and built-up areas (3.0%) at expense of grassland and wetland were noticed, with significant increase in monthly and annual groundwater flow.
Persons with disabilities and resilience: coping with environmental hazards case of landslides in Mount Elgon region, Uganda
(Taylor and Francis- Environmental Hazards,, 2022) Yeeko, Kisira; Martin, Ssennoga; Frank, Mugagga; Daniel, Nadhomi
Adverse impacts on persons with disabilities occur disproportionately during landslide hazards in a rugged landscape. Coping with climate-induced hazards to boost disaster resilience among persons with disabilities is directly influenced by the deepseated power relations in society. The study explored coping mechanisms and assessed their perceived effectiveness in boosting resilience of persons with disabilities in the Ugandan fragile ecosystem. A cross-sectional design with 55 in-depth household interviews, seven key informant interviews and two focus group discussions were used. Quantitative data was analysed using descriptive statistical methods. Content analysis was carried out for qualitative data. Whereas persons with disabilities highly opted for relocation/resettlement, it was also perceived as less effective in boosting landslide resilience. Self- help groups, use of assistive devices, access to early warning, and participation in disaster training and recovery plans in their order of importance-built resilience effectively. In conclusion, Persons with disabilities try to cope with landslide hazards amidst unfavourable power relations and social exclusion. We recommend increased inclusive disaster preparedness and recovery to boost access to information on disaster training, and socio-economic support services. This will directly stimulate the infrastructural, participation, and functioning capacity thus increasing their resilience to Landslides.
Spatio-Temporal Variations in Water Quality and Fish Assemblages in Odoponyi Seasonal Stream as a response to disturbance from Selected Agricultural Landscapes in Tororo, Uganda
(Journal of Applied Sciences and Environmental Management, 2023-09) Turyahabwe, R.; Turyabanawe, G. L; Andama, E.; Othieno, T.; Wamono, E.
This study investigated the Spatio-Temporal Variations in Water Quality and Fish Assemblages in Odoponyi Seasonal Stream as a response to disturbance from Selected Agricultural Landscapes. Six sampling campaigns were launched at three different landscape sampling sites (grazing, rice plantation and sugarcane plantation) for 12 months from January to December of 2022. There was a general trend of increase in Dissolved Oxygen from upstream to downstream in sites in the catchment during both dry (from 7.13±1.9 to 8.9±2.1ppm) and wet seasons (from 11.2±2 to 12.3±01ppm). Plantation landscape of sugarcane registered the highest concentrations of nitrates during both dry and wet seasons (8±0.9 Mg/l and 11±1Mg/l) respectively. There was higher water transparency during dry season than wet season. A total of 568 fish individuals belonging to 7 species including Clarias leocephalus, Pamiphals promelas, Notemigonus crysoleucus, Anchoa mitchili, Poecilia reticulata, Barbodes binotatus and Pseudorasbora parva were captured using hand line and seine nets. Fish species diversity, richness and abundancy were higher during the wet season than dry season. Sugarcane plantation landscape registered the highest fish catch during both dry and wet season while grazing landscape registered the lowest catch at all times. This study recorded presence of a rare migratory fish species Notemigonus cryseleucus in wet season. We concluded that Odoponyi stream has migratory fish species that require protection especially during wet season. We recommended that land users in the catchment should leave a buffer strip of about 10m from the stream bank to reduce on the effect of erosion deposition directly into the stream.
Resilience of persons with disabilities to climate induced landslide hazards in the vulnerable areas of Mount Elgon, Uganda
(International Journal of Disaster Risk Reduction, 2022-10) Daniel, Nadhomi; Frank, Mugagga; Yeeko, Kisira; Martin, Ssennoga;
The resilience of persons with disabilities in landslide-prone areas is not well understood. Moreover, these disasters are persistent and this information is vital in enhancing socioeconomic transformation of the livelihoods of Persons with disabilities. We anchored the resilience of Persons with disabilities to landslide hazards on four factors, namely; risk exposure, socioeconomic capacity, the individual functioning capacity, and the individual's housing infrastructure. The objectives of the study were (i) to assess the level of resilience of Persons with disabilities to landslides and (ii) to explore the significant sociodemographic factors that underpin the resilience of Persons with disabilities to landslides. We used a cross-sectional design and snowball sampling to access the households respondents for interviews. The analysis included descriptive analysis and inferential statistics computed using in Statistical Package for Social Sciences (SPSS) Version 23 and Microsoft Excel version 2016. The geometric mean method was used to assess the level of resilience. The Chisquare and Kendals' Tau-b were used to ascertain the underpinning sociodemographic factors to the resilience of Persons with disabilities. Results revealed that the overall resilience was low. Sex, education level, and access to disaster training significantly controlled resilience among Persons with disabilities. We conclude that Persons with disabilities in landslideprone areas have low resilience and receive little attention with respect to rescue and recovery amidst these recurrent hazards in the area. There is a need to boost the resilience of Persons with disabilities, especially the housing infrastructure and functioning capacity taking into account their social networks to build the socioeconomic and preparedness wings of disaster resilience among Persons with disabilities.
Intersecting RUSLE modelled and farmers perceived soil erosion risk in the conservation domain on mountain Elgon in Uganda
(Elsevier, 2020-11) Yazidhi, Bamutaze; Paul, Mukwaya; Shuichi, Oyama; Daniel, Nadhomi; Peter, Nsemire
This study investigated the intersection between empirically derived and farmers perceived soil erosion risk in a medium-sized catchment on the Ugandan side of mountain Elgon. We postulated that farmers' perception of soil erosion risk was high and this influenced their employment of Soil and Water Conservation (SWC) measures on their land. An adapted Revised Universal Soil Loss Equation (RUSLE) was employed to model the soil erosion risk in a Geographical Information System (GIS) environment. Participatory Learning and Action (PLA) tools covering household interviews and Focus Group Discussions (FGDs) were implemented in two representative subcounties of the catchment to elicit information on farmers' perception of soil erosion risk. Household interviews covering 184 respondents were georeferenced using a Geographical Positioning System (GPS). Farmers perceived soil erosion risk on their land was then matched with RUSLE modelled risk using GPS positional data. The modelled soil erosion risk was substantial and a sizeable proportion of the catchment (63%) exhibited soil losses >10 t ha-1 yr-1, which is considered above the tolerable limit for mountain environments. A slight but significant agreement (p < 0.001) between the modelled and farmers perceived soil erosion risk was observed. In general, farmers perceived soil erosion risk was less than the RUSLE model estimates. Although 95% of farmers recognize soil erosion as problematic, only 65% implemented some aspect of SWC on their land albeit with varied purposes. Chi-square tests did not detect a strong association (p > 0.05) between farmers' perceived soil erosion risk and implementation of SWC on their land. On this basis, our postulation that perceived high soil erosion risk influences the implementation of SWC does not suffice in the studied catchment. We surmise that successful risk mitigation should be directed more on increasing farmer's awareness of the long-term adverse consequences of soil erosion on their land.
Water hyacinth’s extent and its implication on water quality in Lake Victoria, Uganda
(The Scientific World Journal, 2023-03) Hussein, Kiyemba; Bernard, Barasa; Joyfred, Asaba; Paul, Makoba Gudoyi; Gertrude, Akello
Water hyacinth (Eichhornia crassipes) degrades and obstructs the integrity of freshwater ecosystems. However, little attention has been paid to monitoring water hyacinth’s spatial extent, its determinants, and its efects on water quality in Lake Victoria, Uganda. Te specifc objectives of this paper are to (i) assess the spatial extent and distribution of water hyacinth; (ii) examine the determinants of water hyacinth distribution, and (iii) assess its impact on water quality. High-resolution satellite images (2016–2019) were obtained and used to monitor the spatial extent of the water hyacinth, a household survey was conducted to examine the determinants of the water hyacinth’s extent and patterns while water samples were drawn and analysed for physicochemical properties. Results show that the coverage and distribution of water hyacinth varied over space and time. Water hyacinth coverage primarily increased with a decrease in water surface area. Te perceived factors that triggered the water hyacinth spread included the morphology of the Bay, efuent discharge, strong winds, speed of water current, water-level changes, ferry navigation, and construction activities at the shore. Water parameters signifcantly impacted by hyacinth were pH, TP, BOD, COD, DO, turbidity, and transparency. Tis study recommends the strict development and implementation of integrated weed control measures, catchment management plans, and point and nonpoint pollution source control.
Mapping the susceptibility of persons with disabilities to landslides in a highland landscape of Bushika Sub County, Mount Elgon, Eastern Uganda
(Jàmbá - Journal of Disaster Risk Studies, 2022-01) Ssennoga, Martin; Mugagga, Frank; Kisira, Yeeko; Nadhomi, Daniel Luliro
Terrain parameters such as slope aspect, angle, curvature, stream power and altitude have been noted to spur landslide occurrence as well as, acting as a hindrance to evacuation efforts. Yet, persons with disabilities (PWDs) are seldom given priority during rescue and recovery programmes during pre- and post-disaster evacuation. The study was guided by two objectives, namely, (1) to map the landslide risk for households of PWDs and (2) to investigate the disability type that is perceived to be most affected by landslides. A cross-sectional household survey was adopted employing snowball sampling, Key Informant Interviews (KII), and Focus Group Discussions (FGDs) for primary data collection. A 30-m Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) was used for terrain spatial landslide risk analysis in ArcGis 10.8 and System for Automated Geoscientific Analyses (SAGA) tools. A one-sample t-test in Statistical Package for Social Sciences (SPSS) version 23 was used to analyse the score values on a five-point Likert scale to ascertain the perceived landslide effect on the different disability categories. Qualitative data was subjected to content analysis. We found out that majority of PWDs live in high-risk landslide zones with 1400 m – 1700 m, S-E, 10–80, > 10, and –0.8–0.13 of altitude, aspect, slope angle, Stream Power Index (SPI), and slope curvature, respectively. T-test results revealed that blind and deaf-blind were perceived as most affected by landslides with t(31) = 58.42, mean = 4.7, p < 0.0001, and t(31) = 34.8, mean 4.6, p < 0.0001. The deaf people were perceived to also be highly affected by landslides with t(31) = 34.4, mean = 3.9, p < 0.0001. In conclusion, PWDs in Bushika were highly susceptible to landslide hazards and yet considered as a minority for rescue and recovery during landslide occurrences. We recommend for prioritisation of inclusive disaster programmes such as disaster training, relocation, and resettlement to reduce vulnerability and enhance landslides disaster resilience of PWDs especially in high-risk areas.
Understanding the drivers of adoption of organic banana farming technologies in Kajara County, South-western Uganda
(East African Journal of Agriculture and Biotechnology, 2022) Atwijukye, Dunstan; Turyahabwe, Remigio; Nabalegwa, Muhamud Wambede; Asaba, Joyfred
This study aimed at identifying and characterising the major organic banana farming technologies used and assessing the drivers of adoption of the same in Kajara County. A total of 360 respondents were used to obtain primary data. As the study adopted a cross-sectional design, we used questionnaires, interviews, focus group discussions, and field observations to collect the required data. Data was analysed using descriptive statistics and the non-parametric (Chi-square) tests. Results indicate that the major organic banana farming technologies adopted in the study area were mulching, cover cropping, farmyard manure application, pest and weed management. The chi-square test revealed that the marital status, gender, and level of education of the farmers had significant positive effects on the adoption of organic banana farming technologies among the farmers. We concluded that, generally, the rate of adoption of organic farming technologies in Kajara County was low, and therefore, there is a need for emphasising the training of the farmers at local levels so as to equip them with information on the organic farming technologies for sustainable banana farming. We recommend that stakeholders who work on agricultural programs use model farmers in the area to educate and demonstrate the importance of organic banana farming technologies.
Factors affecting the adoption of soil and water conservation practices by small-holder farmers in Muyembe Sub-County, Eastern Uganda
(Ghana Journal of Geography, 2022-08) Turyahabwe, Remigio; Nabalegwa, Muhamud Wambede; Asaba, Joyfred; Mulabbi, Andrew; Gumisiriza, Loy Turyabanawe
Farmers in tropical rural areas are confronted with several challenges but outstanding among these challenges is soil degradation arising from soil erosion. This study involved identifying the dominant soil and water conservation practices and assessing the factors affecting their adoption in the Muyembe sub-county, Eastern Uganda. A total of 500 respondents were used to obtain primary data. As the study adopted a cross- sectional design, we used questionnaires, interviews, focus group discussions and field observations to collect the required data. Data were analyzed using descriptive statistics and the non-parametric (Chi-square) test. The results indicated that the dominant soil and water conservation practices adopted in the study area were, contour cropping (77%), mixed cropping (59% and crop rotation (51%). The remaining five practices had less than a 50% adoption rate. The chi-square test revealed that the age and gender of the farmers had a significant association with the levels of the adoption of soil and water conservation practices among farmers at P<0.001. We concluded that the adoption of soil and water conservation practices was low, which left the majority of farmers vulnerable to soil erosion effects such as low yields and crop failure. We recommend that stakeholders who work on soil and water conservation programs use model farmers in the area to educate and demonstrate the importance of soil and water conservation practices to other farmers.
Adoption of Water Conservation Technologies among Small Scale Farmers in Lwengo District – Uganda
(African Journal of Inter/Multidisciplinary Studies, 2019) Nabalegwa, Muhamud Wambede; Asaba, Joyfred; Othieno, Esther Ebifa; Nabatta, Claire
This study identified and characterised the dominant water conservation technologies (WCT) employed by small scale farmers in Malongo and Kyazanga sub-counties in Lwengo district. It employed a cross sectional household survey design, using systematic sampling to obtain 380 household samples. A quantitative analysis, Multiple Correspondence Analysis (MCA) and Logit regression model were used to analyse these data to identify and characterise the dominant WCT and establish the most significant factor affecting the adoption of the technologies. Results indicated that mulching was the most dominant WCT employed, followed by Valley dams/reservoirs, terracing, tied ridges, deep tillage and infiltration pits. The Logit model indicated that out of seven factors, five had a significant positive influence namely: access to credit (1.3); farm slope location (0.7); farm size (0.4); access to agricultural inputs and investment subsidies (0.4); and level of income (0.2). One factor had a significant negative influence (engagement in other economic activities/off-farm employment activities) and only one was found to be insignificant (access to market). It is recommended that the significant water conservation techniques be upscaled, and that emphasis also be placed on the most significant factors in order to strengthen the adoption of water conservation in the area.
Community based flood risk management approach in Northeastern Uganda
(Ghana Journal of Geography, 2022-06) Muhamud, Nabalegwa Wambede; Robert, Tweheyo
This study was conducted in the Amuria district of Northeastern Uganda. The aim of the study was to assess the performance of Community Based Disaster Risk Reduction (CMDRR) approach in mitigating disaster effects in the area. The objectives were to assess the effectiveness of community preparedness, response, and recovery efforts in mitigating disasters in the study area. Aberilela and Wera sub-counties were purposively selected, and two parishes were chosen from each of the two sub counties based on their vulnerability to flood disasters. A sample of 300 household heads were randomly selected. Methods of data collection included questionnaires, in-depth interviews with key informants, focus group discussions, observation, and documents review. The collected data were analysed using descriptive statistics and triangulated with thematic analysis of the data from interviews and field observations. Results from the study indicate that the CMDRR approach had performed well despite some shortcomings. The approach had been able to prepare the community by training them in disaster management activities, developing hazard prone maps, disaster plans, established effective rescue measures and other response measures for the affected communities. However, it had failed in building capacity among the communities to stock essential services including food, early warning systems and in detecting and predicting disaster as well as building gender and age balanced capacity in the communities. Overall, the performance of CMDRR committees in Amurai and particularly Abarilela and Wera sub-counties was above average. The study recommends that government should adopt this approach and replicate it in other disaster-prone areas for effective disaster management.
Hydrologic response to land use/cover changes and Pteronia incana shrub invasion in Keiskamma catchment, Eastern Cape Province, South Africa
(Geocarto International, 2022-02-07) Mlamla, Sive; Kakembo, Vincent; Barasa, Bernard
The Keiskamma catchment has undergone significant land use/cover changes (LUCC) and invasion by Pteronia incana (P. incana) shrub, and the hydrological implications of the phenomena are not fully understood. This study assessed the hydrological response of the catchment using remote sensing per-pixel classification, the SWAT model between 1994 and 2016, and field experiments. Results revealed a significant increase in woody vegetation encroachment and a decrease in mean annual streamflow, runoff, soil water content, evapotranspiration and groundwater. However, high surface runoff, and sediment loss were evident under P. incana invader shrub at hillslope scale. The study concludes that the hydrological response of the catchment was influenced significantly by LUCC in the form of extensive invader shrub encroachment, expansion of exotic forest tree species, impoundments and infestation of riparian zones by invasive vegetation. Control of alien invasive plants and utilization of indigenous forest species are recommended for catchment management.
The energy potential of harvested wood fuel by refugees in Northern Uganda
(The Scientific World Journal : Hindawi, 2022-02-22) Barasa, Bernard; Turyabanawe, Loy; Akello, Gertrude; Gudoyi, Paul Makoba; Nabatta, Claire; Mulabbi, Andrew
For the last three decades, Uganda has lost considerable natural vegetation cover in the refugee settlements and buffer zones due to the high demand for wood fuel and timber. It is worthy to note that the supplies of wood fuel are more likely to dwindle in the near future. This study explored the determinants of harvested wood-fuel choices and their energy potential. It also examined the implemented energy conservation measures and constraints faced by the refugees both in Palorinya and Imvepi refugee settlements in Northern Uganda. The data were collected by conducting household interviews and collection of wood species samples for energy potential laboratory analysis. Findings indicate that the major sources of wood fuel were firewood, charcoal, briquettes, and biomass fuels. The major refugee choices that determined wood-fuel collection included the family size of the house hold, culture, method of cooking, type of food cooked, high poverty levels, and availability of family labour (). The sampled wood tree species had the highest energy potential were Celtis durandii (5,837 kcal/kg), Parkinsonia aculeata (5,771 kcal/kg), Delonix regia (5,153 kcal/kg), and Bligihia unijugata (5,034 kcal/kg). Access to wood fuel by the households was mainly constrained by limited household income levels, long distances trekked, and inadequate awareness about wood fuel sources and availability. To conserve wood fuel, the refugees deploy several measures including the use of mobile solar gadgets for cooking and lighting, taking up agroforestry, use of briquettes, adoption of energy-saving cooking stoves, and establishment of new woodlots. Therefore, to reverse this trend, the Ugandan government and development partners should prioritise energy investments by supporting cheaper energy alternatives such as mobile solar gadgets and energy-saving cooking technologies, and establishment of woodlots.
Effect of mulching and permanent planting basin dimensions on Maize (Zea mays L.) production in a Sub-Humid Climate
(Water : MDPI, 2022-01-03) Zizinga, Alex; Mwanjalolo, Jackson-Gilbert Majaliwa; Tietjen, Britta; Bedadi, Bobe; Gabiri, Geofrey; Luswata, Kizza Charles
In sub-humid regions, declining maize (Zea mays L.) yield is majorly attributed to unreliable rainfall and high evapotranspiration demand during critical growth stages. However, there are limited farm technologies for conserving soil water and increasing water use efficiency (WUE) in rainfed production systems amidst a changing climate. This study aimed at assessing the performance of different climate smart agriculture (CSA) practices, such as mulching and permanent planting basins (PPB), on maize growth, yield, water use efficiency and soil moisture storage. Field experiments involving mulches of 2 cm (M_2 cm), 4 cm (M_4 cm) and 6 cm (M_6 cm) thickness, permanent planting basins of 20 cm (PPB_20 cm) and 30 cm (PPB_30 cm) depths and the control/or conventional treatments were conducted for three maize growing seasons in the sub-humid climate of Western Uganda. Results indicate that maize biomass significantly increased under the tested CSA practices in the study area. Use of permanent planting basins relatively increased maize grain yield (11–66%) and water use efficiency (33–94%) compared to the conventional practice. Additionally, plots treated with mulch achieved an increase in grain yield (18–65%) and WUE (28–85%) relative to the control. Soil amendment with M_4 cm and M_6 cm significantly increased soil moisture storage compared to permanent planting basins and the conventional practice. Overall, the results highlight the positive impact of CSA practices on improving maize yield and water use efficiency in rainfed agriculture production systems which dominate the sub-humid regions
Contribution of rainfall on rooftop rainwater harvesting and saving on the slopes of Mt. Elgon, East Africa
(Hindawi: The Scientific World Journal, 2020-07-18) Barasa, Bernard; Asaba, Joyfred
Despite the achievements reported from using rainwater harvesting systems, the contribution and drawbacks that affect their usage in mountainous landscapes have received little attention. The uptake and usage of domestic rooftop rainwater harvesting systems (RRWHS) in developing countries is on the increase due to increasing water scarcities. We explored the effect of rainfall variability on water supply and the downsides of using the systems by rural households in Uganda. The objectives were to assess the variability of rainfall (1985–2018), categorise RRWHS used, and examine the influence of slope ranges on the placement of systems and also to quantify the harvested and saved rainwater and establish the factors that affected system usage. Rainfall variability was assessed using a Mann–Kendall test, while system contributions and drawbacks were examined using socioeconomic data. A representative of 444 households were selected using a multicluster sampling procedure and interviewed using semistructured questionnaires. Findings revealed that the months of March, April, September, August, and October experienced an upward trend of rainfall with a monthly coefficient of variation between 41 and 126%. With this, households responded by employing fixed (reinforced concrete tanks, corrugated iron tanks, and plastic tanks) and mobile RRWHS (saucepans, metallic drums/plastic drums, jerrycans, and clay pots). At the high altitude, households deployed mostly plastic jerrycans and industrial plastic/metallic drums to harvest and save water. Overall, the mean annual volume of rainwater harvested on the slopes of Mt. Elgon was 163,063 m3/yr, while the potential to save water ranged from 4% to 7% of the annual household water demand. The factors that hindered the deployment of RRWHS to harvest and save water were high operational costs, price fluctuations, unreliable rainfall pattern, inadequate funds, and limited accessibility. The rainfall received if well-harvested and saved can redeem households of water insecurity, though there is an urgent need of subsidies from the government to increase accessibility of the systems.
Past, present and future climate trends under varied representative concentration pathways for a sub-humid region in Uganda
(MDPI: Climate, 2019-02-26) Egeru, Anthony; Barasa, Bernard; Nampijja, Josephine; Siya, Aggrey; Makooma, Moses Tenywa; Majaliwa, Mwanjalolo G. J.
Long-term trend analysis at local scale for rainfall and temperature is critical for detecting climate change patterns. This study analysed historical (1980–2009), near future (2010–2039), mid- (1940–2069) and end-century (2070–2099) rainfall and temperature over Karamoja sub-region. The Modern Era-Retrospective Analysis for Research and Applications (MERRA) daily climate data provided by the Agricultural Model Inter-comparison and Improvement Project (AgMIP) was used. The AgMIP delta method analysis protocol was used for an ensemble of 20 models under two representative concentration pathways (RCPs 4.5 and 8.5). Historical mean rainfall was 920.1 ± 118.9 mm and minimum, maximum and mean temperature were 16.8 ± 0.5 °C, 30.6 ± 0.4 °C and 32.0 ± 0.7 °C, respectively. Minimum temperature over the historical period significantly rose between 2000 and 2008. Near future rainfall varied by scenario with 1012.9 ± 146.3 mm and 997.5 ± 144.7 mm for RCP4.5 and RCP8.5 respectively; with a sharp rise predicted in 2017. In the mid-century, mean annual rainfall will be 1084.7 ± 137.4 mm and 1205.5 ± 164.9 mm under RCP4.5 and RCP8.5 respectively. The districts of Kaabong and Kotido are projected to experience low rainfall total under RCP4.5 (mid-century) and RCP8.5 (end-century). The minimum temperature is projected to increase by 1.8 °C (RCP4.5) and 2.1 °C (RCP8.5) in mid-century, and by 2.2 °C (RCP4.5) and 4.0 °C (RCP8.5) in end-century.
Freshwater lake inundation monitoring using Sentinel-1 SAR imagery in Eastern Uganda
(Taylor&Francis Online: Annals of GIS, 2020-03-18) Barasa, Bernard; Wanyama, Joshua
In flood hazard assessment, little attention has been given to the seasonal observation of freshwater inundation using Sentinel-1 Synthetic-Aperture Radar (SAR) images in the tropics. To assess these spatial variations, this study examined the inundation magnitudes and reflectance of riparian flora in the raining seasons (February-April and September-November) and dry-periods (May-August and December-January). The inundation areas were determined using an object-oriented classification algorithm, whilst the merits concerning the lake, riparian vegetation and shoreline were well-defined using backscatter-coefficient values. Findings indicated that the SAR images are practical to monitor inundation coverages and discern lake basin specific features such as highland areas, shoreline, water and riparian-vegetation. Seasonally, inundated sizes were comparatively higher in February (902 sq. km) and October (700 sq.km). Backscatter values of inundated parts varied from −16 dB to −19 dB, whereas those of riparian vegetation were higher in the months of May and August. This study hence displays a clear-cut correlation between riparian-vegetation, hydrology and climate variables.
The impact of refugee settlements on land use changes and vegetation degradation in West Nile sub-region, Uganda
(Taylor&Francis Online: Geocarto International, 2020-07-31) Barasa, Bernard; Mwiru, Aron; Turyabanawe, Loy; Muhamud, Nabalegwa W.; Ssentongo, Benard
Uganda continues to experience high-refugee population influx that is beyond the established settlement capacities. Little information is available on the present and future impacts of settling refugees and host-communities on landuse changes and vegetation degradation. This study used Sentinel-2 images (20m) of 2016-2019 and Dinamica Ego-software to determine the current and future spatial areal-extent of changes in 2022. Findings revealed a rarefied increase in areas under subsistence-farming, builtups and refugee-settlements while the losses were seen in savannah-grasslands, wetlands and woodlands. In 2021, the most significant increases in the land will be experienced in builtup-areas, settlements and commercial farming. The most degraded vegetation types were savannah-grassland, woodlands and tree-plantations. These were primarily attributed to unending activities of deforestation, bush-burning, high-refugee population, land-conflicts with host-communities and wetland reclamation. Thus, unless sustainable farming and energy-saving practices are promoted and adopted, the landscape is likely to remain not even with remnants of green-cover.
A pattern driven approach to knowledge representation in the disaster domain
(Springer Link: SN Computer Science volume., 2020-10-22) Mazimwe, Allan; Hammouda, Imed; Gidudu, Anthony; Barasa, Bernard
Access to integrated disaster-related data through querying is still a problem due to associated semantic barriers. The disaster domain largely relies on the top–down approach of ontology development. This limits reuse due to associated commitments and complex alignments within ontologies. Therefore, there is a need to utilize a bottom-up approach that reuses patterns for representing disaster knowledge. To bridge the availability gap of patterns for representing disaster knowledge, this study identifies existing and emerging patterns for reuse while organizing disaster data from multiple sector stakeholders. Based on the eXtreme Design (XD) methodology and key informant interviews, competency questions (CQs) were elicited from domain stakeholders. The CQs are matched with existing patterns from other contexts. Emerging patterns (e.g the Event Classification and Quality Dependence Description for Objects) are also developed for CQs not captured and subsequently tested using SPARQL queries characterising the CQs. It is in this context that this paper presents a characterisation of disaster risk knowledge using CQs and corresponding patterns (reusable and emerging) covering the knowledge. Accordingly, we illustrate a pattern-driven use case to organise drought hazard data for early warning purposes. This provides a powerful use case for adopting a pattern-based approach to knowledge representation in the disaster domain.

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