140 research outputs found

    Chemical quality of common beans as influenced by genotype and aluminium rates under two soil liming regimes

    Get PDF
    Soil acidity affects seed yield and crop quality negatively due to aluminium toxicity in most humid tropics where the crop is cultivated for food and cash income by smallholder farmers. This study was conducted to assess the effect of different exchangeable aluminium concentrations on bean chemical quality of two common bean genotypes grown on lime-treated and lime-untreated soils. Factorial combinations of five aluminium rates (0.0, 12.5, 25.0, 50.0, and 100.0 mg Al/ kg soil) and two common bean genotypes (New BILFA 58 and Roba 1) were laid out in a completely randomized design with three replications. For each treatment, four plants were raised per pot in the vegetation hall of Nekemte Soil Laboratory, western Ethiopia. The experiment was established in two sets: lime-treated soil and lime-untreated soil. The results revealed that aluminium toxicity caused major changes in the composition of the common beans. Significant differences (P < 0.01) were found among the different aluminium rates and between the two genotypes for bean crude protein, crude fibre, crude fat, and ash, carbohydrate, calcium, magnesium, and aluminium contents under both liming regimes. The interaction of aluminium and genotype also influenced most of the bean chemical quality attributes negatively. New BILFA 58 (acidic soil tolerant genotype) had better bean chemical quality attributes (except aluminium and condensed tannins contents) than Roba 1 (acidic soil sensitive genotype) under both liming regimes. On the average, lime application increased bean crude protein, crude fat, ash, and calcium contents by 4.1%, 20.7%, 7.9%, and 11.7%, respectively. However, it decreased bean crude fibre and aluminium contents. Bean carbohydrate and condensed tannin contents of the genotypes increased in response to increasing aluminium application under both liming regimes. The total ash, which is an indirect indicator of the mineral content of foodstuffs, was found to be higher for New BILFA 58 than Roba 1 under both liming regimes. In conclusion, the results of this study have demonstrated that increased soil aluminium contents have significant negative effects on common bean quality, but integrated use of tolerant genotypes and application of lime can simultaneously alleviate the problem of low yield and reduced bean nutritional quality of the crop.Keywords: Aluminium, proximate, Lime, soil, Phaseolusvulgari

    A Modeling Approach to Determine the Impacts of Land Use and Climate Change Scenarios on the Water Flux of the Upper Mara River

    Get PDF
    With the flow of the Mara River becoming increasingly erratic especially in the upper reaches, attention has been directed to land use change as the major cause of this problem. The semi-distributed hydrological model Soil and Water Assessment Tool 5 (SWAT) and Landsat imagery were utilized in the upper Mara River Basin in order to 1) map existing field scale land use practices in order to determine their impact 2) determine the impacts of land use change on water flux; and 3) determine the impacts of rainfall (0%, ±10% and ±20%) and air temperature variations (0% and +5%) based on the Intergovernmental Panel on Climate Change projections on the water flux of the 10 upper Mara River. This study found that the different scenarios impacted on the water balance components differently. Land use changes resulted in a slightly more erratic discharge while rainfall and air temperature changes had a more predictable impact on the discharge and water balance components. These findings demonstrate that the model results 15 show the flow was more sensitive to the rainfall changes than land use changes. It was also shown that land use changes can reduce dry season flow which is the most important problem in the basin. The model shows also deforestation in the Mau Forest increased the peak flows which can also lead to high sediment loading in the Mara River. The effect of the land use and climate change scenarios on the sediment and 20 water quality of the river needs a thorough understanding of the sediment transport processes in addition to observed sediment and water quality data for validation of modeling results

    Evaluation of static and dynamic land use data for watershed hydrologic process simulation: A case study in Gummara watershed, Ethiopia

    Get PDF
    Land Use Land Cover (LULC) change significantly affects hydrological processes. Several studies attempted to understand the effect of LULC change on biophysical processes; however, limited studies accounted dynamic nature of land use change. In this study, Soil and Water Assessment Tool (SWAT 2012) hydrological model and statistical analysis were applied to assess the impacts of land use change on hydrological responses such as surface runoff, evapotranspiration, and peak flow in Gummara watershed, Ethiopia. Moreover, the effects of static and dynamic land use data application on the SWAT model performance were evaluated. Two model setups, Static Land Use (SLU) and Dynamic Land Use (DLU), were studied to investigate the effects of accounting dynamic land use on hydrological responses. Both SLU and DLU model setups used the same meteorological, soil, and DEM data, but different land use. The SLU setup used the 1985 land use layer, whereas the DLU setup used 1985, 1995, 2005, and 2015 land use data. The calibration (validation) results showed that the model satisfactorily predicts temporal variation and peak streamflow with Nash Sutcliffe Efficiency (NSE) of 0.75 (0.71) and 0.73 (0.71) in the DLU and SLU setups, respectively. However, the DLU model setup simulated the detailed biophysical processes better during the calibration period. Both model setups equally predicted daily streamflow during the validation period. Better performance was obtained while applying the DLU model setup because of improved representation of the dynamic watershed characteristics such as curve number (CN2), overland Manning's (OV_N), and canopy storage (CANMX). Expansion of agricultural land use by 11.1% and the reduction of forest cover by 2.3% during the period from 1985 to 2015 increased the average annual surface runoff and peak flow by 11.6 mm and 2.4 m3/s, respectively and decreased the evapotranspiration by 5.3 mm. On the other hand, expansion of shrubland by 1% decreased the surface runoff by 1.2 mm and increased the evapotranspiration by 1.1 mm. The results showed that accounting DLU into the SWAT model simulation leads to a more realistic representation of temporal land use changes, thereby improving the accuracy of temporal and spatial hydrological processes estimation

    Geographic variation and factors associated with female genital mutilation among reproductive age women in Ethiopia: A national population based survey

    Get PDF
    Background: Female genital mutilation (FGM) is a common traditional practice in developing nations including Ethiopia. It poses complex and serious long-term health risks for women and girls and can lead to death. In Ethiopia, the geographic distribution and factors associated with FGM practices are poorly understood. Therefore, we assessed the spatial distribution and factors associated with FGM among reproductive age women in the country. Method: We used population based national representative surveys. Data from two (2000 and 2005) Ethiopian demographic and health surveys (EDHS) were used in this analysis. Briefly, EDHS used a stratified, two-stage cluster sampling design. A total of 15,367 (from EDHS 2000) and 14,070 (from EDHS 2005) women of reproductive age (15-49 years) were included in the analysis. Three outcome variables were used (prevalence of FGM among women, prevalence of FGM among daughters and support for the continuation of FGM). The data were weighted and descriptive statistics (percentage change), bivariate and multivariable logistic regression analyses were carried out. Multicollinearity of variables was assessed using variance inflation factors (VIF) with a reference value of 10 before interpreting the final output. The geographic variation and clustering of weighted FGM prevalence were analyzed and visualized on maps using ArcGIS. Z-scores were used to assess the statistical difference of geographic clustering of FGM prevalence spots. Result: The trend of FGM weighted prevalence has been decreasing. Being wealthy, Muslim and in higher age categories are associated with increased odds of FGM among women. Similarly, daughters from Muslim women have increased odds of experiencing FGM. Women in the higher age categories have increased odds of having daughters who experience FGM. The odds of FGM among daughters decrease with increased maternal education. Mass media exposure, being wealthy and higher paternal and maternal education are associated with decreased odds of women's support of FGM continuation. FGM prevalence and geographic clustering showed variation across regions in Ethiopia. Conclusion: Individual, economic, socio-demographic, religious and cultural factors played major roles in the existing practice and continuation of FGM. The significant geographic clustering of FGM was observed across regions in Ethiopia. Therefore, targeted and integrated interventions involving religious leaders in high FGM prevalence spot clusters and addressing the socio-economic and geographic inequalities are recommended to eliminate FGM. © 2016 Setegn et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
    • …
    corecore