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Muhire I.,University of Johannesburg | Muhire I.,College of Education, University of Rwanda | Ahmed F.,University of Witwatersrand | Abutaleb K.,University of Johannesburg | Kabera G.,South African Medical Research Council
International Journal of Plant Production | Year: 2015

This paper investigated the response of major food crop yields namely beans, cassava, Irish potatoes, maize and sweet potatoes to ongoing changes in climate in Rwanda. The projected daily precipitation and temperature data for the period 2000-2050 used in this study were generated by stochastic weather generator (LARS-WG) from daily raw data for the period 1961-2000. These data were collected from Rwandan Meteorological Center based in Kigali, while the agricultural records for the period 2000-2010 used to project yields of major food crops for 2011-2050 were obtained from the National Institute of Statistics of Rwanda and the Ministry of Agriculture and Animal Resources. A number of statistical techniques were applied in projecting the major food crops yields and attempting to quantify their magnitude trends in response to projected precipitation and temperature data. The climate and soil suitability analysis revealed that the central plateau and south-west regions of the country will be the most suitable regions for cultivation of major food crops except Irish potatoes which can be grown in the north-western highlands. The central plateau region is the only region that is expected to experience an increase in yields for most of the major food crops under investigation. The south-west region will have increased beans, cassava and sweet potatoes yields in season A (September-January). The eastern lowlands are expected to register a decreasing trend in most of crops yields in season A, corresponding to the anticipated decline in mean rainfalls and number of rainy days. The envisaged yields increase in season B (February-June) for beans, maize and Irish potatoes will be in response to a rise in mean rainfall and number of rainy days. Heavy rainfall in the north-western region is likely to have a negative impact on crop yields. The rain might cause waterlogging, flooding events and landslides which may damage and destroy the crops. © 2015, Gorgan univ agricultural sciences and natural resources. All right reserved. Source

Tsinda A.,College of Education, University of Rwanda | Abbott P.,University of Aberdeen | Chenoweth J.,University of Surrey
Habitat International | Year: 2015

This article analyses sanitation markets in the informal settlements of three case study cities, namely Kigali (Rwanda), Kampala (Uganda) and Kisumu (Kenya), to identify how sanitation markets in East Africa can be made to function more effectively. It is based on a mixed method approach where 1794 households from Kigali, 1666 households from Kampala and 1927 households from Kisumu were surveyed. This was complemented by qualitative research involving 83 focus group discussions, 99 interviews and 3 deliberative forums. Findings reveal similarities and strong differences between the cities in terms of sanitation markets. While construction and emptying services are more available in Kampala and to lesser extent in Kisumu, organic solutions are mostly available in Kigali. However, the purchase of products and services is generally low. One of the reasons is that households are provided with products they do not want to buy. The sanitation intervention should be focused on the households rather than the suppliers of sanitary products. This involves understanding consumers' needs, desires, habits and the circumstances required for a facility to be acceptable and meet the needs of users rather than what fits the supplier. © 2015 Elsevier Ltd. Source

Nsanganwimana F.,Laboratoire Genie Civil et geo Environnement LGCgE | Nsanganwimana F.,College of Education, University of Rwanda | Pourrut B.,Laboratoire Genie Civil et geo Environnement LGCgE | Waterlot C.,Laboratoire Genie Civil et geo Environnement LGCgE | And 9 more authors.
Agriculture, Ecosystems and Environment | Year: 2015

The choice of agronomic practices for phytomanagement of metal-contaminated soils is of crucial importance to optimize plant biomass yields and to mitigate both environmental and health risks due to metal exposure. The present study aimed to assess the effects of agronomic practices on shoot yield and on metal (Cd, Pb, and Zn) accumulation in the organs of the energy crop miscanthus (Miscanthus×giganteus) during the first three years since the plantation on metal-contaminated agricultural soils. Three miscanthus cultivars, hereafter named Mis-A, Mis-B and Mis-I, were planted at low and high density. An inoculum of arbuscular mycorrhizal fungi-AMF (Glomus LPA Val 1) was added during plantation, and nitrogen fertilization was applied during the third growing season. Metal accumulation in miscanthus organs was determined during the second growing season, whereas shoot yields and their metal concentrations were determined during both the second and the third growing seasons. Based on metal concentrations and bioconcentration factors, the three cultivars mainly accumulated metals in their roots. The shoot yields increased from 3.7 to 10.3 t DWha-1 in the second growing season to 15.8-23.3 t DWha-1 in third growing season. There were no or very few significant differences in metal concentrations and shoot yields within treatments comprising the same cultivar. The addition of AMF inoculum increased metal (mainly Cd and Zn) accumulation in miscanthus organs and in the shoot yields and this was more observed in both Mis-B and Mis-I which presented a higher root mycorrhization level than in Mis-A. Shoot yields in treatments comprising different cultivars depended not on fertilization but on the interactions between cultivar and planting density, and between cultivar, planting density and AMF inoculum. Whatever the treatment and the sampling period, Pb concentrations did not significantly differ in shoot yields. The interaction between cultivar and planting density resulted in higher Cd concentrations in the yields of Mis-B planted at low density during the third growing season. Zn concentrations increased with fertilization in all treatments, and with the addition of the AMF inoculum in Mis-B and in Mis-I. Overall, the results demonstrated that the three cultivars could be potential candidates for coupling phytostabilization and biomass production on metal-contaminated soils. © 2015 Elsevier B.V. Source

Muhire I.,University of Johannesburg | Muhire I.,College of Education, University of Rwanda | Ahmed F.,University of Witwatersrand | Abutaleb K.,University of Johannesburg
Theoretical and Applied Climatology | Year: 2015

This study aims primarily at investigating the relationships between Rwandan seasonal rainfall anomalies and El Niño-South Oscillation phenomenon (ENSO) events. The study is useful for early warning of negative effects associated with extreme rainfall anomalies across the country. It covers the period 1935–1992, using long and short rains data from 28 weather stations in Rwanda and ENSO events resourced from Glantz (2001). The mean standardized anomaly indices were calculated to investigate their associations with ENSO events. One-way analysis of variance was applied on the mean standardized anomaly index values per ENSO event to explore the spatial correlation of rainfall anomalies per ENSO event. A geographical information system was used to present spatially the variations in mean standardized anomaly indices per ENSO event. The results showed approximately three climatic periods, namely, dry period (1935–1960), semi-humid period (1961–1976) and wet period (1977–1992). Though positive and negative correlations were detected between extreme short rains anomalies and El Niño events, La Niña events were mostly linked to negative rainfall anomalies while El Niño events were associated with positive rainfall anomalies. The occurrence of El Niño and La Niña in the same year does not show any clear association with rainfall anomalies. However, the phenomenon was more linked with positive long rains anomalies and negative short rains anomalies. The normal years were largely linked with negative long rains anomalies and positive short rains anomalies, which is a pointer to the influence of other factors other than ENSO events. This makes projection of seasonal rainfall anomalies in the country by merely predicting ENSO events difficult. © 2014, Springer-Verlag Wien. Source

Muhire I.,University of Johannesburg | Muhire I.,College of Education, University of Rwanda | Ahmed F.,University of Witwatersrand
Theoretical and Applied Climatology | Year: 2016

This study aims at quantifying the trends in mean temperatures and aridity index over Rwanda for the period of 1961–1992, based on analysis of climatic data (temperatures, precipitations, and potential evapotranspiration). The analysis of magnitude and significance of trends in temperatures and aridity index show the degree of climate change and mark the level of vulnerability to extreme events (e.g., droughts) in different areas of the country. The study reveals that mean temperatures increased in most parts of the country, with a significant increase observed in the eastern lowlands and in the southwestern parts. The highlands located in the northwest and the Congo-Nile crest showed a nonsignificant increase in mean temperatures. Aridity index increased only in March, April, October, and November, corresponding with the rainy seasons. The remaining months of the year showed a decreasing trend. At an annual resolution, the highlands and the western region showed a rise in aridity index with a decreasing pattern over the eastern lowlands and the central plateau. Generally, the highlands presented a nonsignificant increase in mean temperatures and aridity index especially during the rainy seasons. The eastern lowlands showed a significant increase in mean temperatures and decreasing trends in aridity index. Therefore, these areas are bound to experience more droughts, leading to reduced water and consequent decline in agricultural production. On the other hand, the north highlands and southwest region will continue to be more productive. © 2015, Springer-Verlag Wien. Source

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