Browsing by Author "Hensel, Oliver"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Homegardens and the future of food and nutrition security in southwest Uganda
    (Agricultural Systems, 2017) Tabuti, John R.S.; Luedeling, Eike; Whitney, Cory W. a Yehf, Jens Gebauera, Eike Luedelingb; Hensel, Oliver; Yeh, Ching-Hua; Gebauer, Jens
    Governments around the world seek to create programs that will support sustainable agriculture and achieve food security, yet they are faced with uncertainty, system complexity and data scarcity when making such choices. We propose decision modeling as an innovative approach to help meet these challenges and offer a case study to show the effectiveness of the tool. We use decision analysis tools to model the possible nutrition-related outcomes of the Ugandan government's long term agricultural development plan termed ‘Vision 2040’. The analysis indicates potential shifts in household nutritional contributions through the comparison of the current small-scale diverse systems and the envisioned industrial agricultural systems that may replace them. A Monte Carlo simulation revealed that Vision 2040 plans outperform homegardens in terms of energy and some macronutrients, yet homegardens are likely to be better at producing key vitamins and micronutrients, such as Vitamin A. Value of information calculations applied to Monte Carlo outputs further revealed that gathering more data on the annual yields and nutrient contents of staples, pulses, vegetables, and fruits could improve certainty about the nutrition contribution of both scenarios. We conclude that the development of Uganda's agricultural sector should consider the role that agrobiodiversity in the current small-scale agricultural systems plays in national food and nutrition security. Any changes according to Vision 2040 should also include farmers' voices and current crop management systems as guides for a sustainable food supply in the region. This modeling approach may be a tool for governments to consider agricultural policy implications, especially given the data scarcity and agricultural variability in regions such as East Africa.
  • Thumbnail Image
    Item
    Optimization of roughing filtration unit for a handwashing wastewater recirculation point-of-use system
    (Water Science & Technology, 2022) Olupot, Peter Wilberforce; Menya, Emmanuel; Jjagwe, Joseph; Wakatuntu, Joel; Románc, Franz; Hensel, Oliver
    A downward roughing filter unit consisting of silica sand as the filter medium was optimized for performance towards removal of turbidity and suspended solids from handwashing wastewater. Design-Expert software was employed to optimize media particle size, filter depth, and flowrate. Linear and quadratic models were found to best fit the responses of turbidity and suspended solids removal, respectively. Particle size and flow rate were the only parameters with significant effects on removal of turbidity and suspended solids. Optimal conditions were found to be media particle size 0.6 mm, filter depth 12 cm, and flow rate 0.3 Lmin 1, corresponding to removal efficiencies of 62 and 67% for turbidity and total suspended solids (TSS), respectively, as predicted by the model. Validation of model at optimal conditions resulted in turbidity and TSS removal of 55 and 53%, respectively. Additionally, removal efficiencies of the roughing filter towards apparent colour, true colour, biochemical oxygen demand (BOD5), and chemical oxygen demand (COD) from handwashing wastewater were 56, 20, 32, and 5%, respectively. Overall, although turbidity of filtered water was .50 NTU, the reduction achieved by roughing filtration is a significant step in enhancing the performance of water treatment processes downstream, including filtration and adsorption by slow sand filters and activated carbon, respectively.
  • Thumbnail Image
    Item
    The Role of Homegardens for Food and Nutrition Security in Uganda
    (Human Ecology, 2018) Whitney, Cory William; Luedeling, Eike; Hensel, Oliver; Tabuti, John R. S.; Krawinke, Michael; Gebauer, Jens; Kehlenbeck, Katja
    The contribution of homegardens to the food and nutrition security of rural farmers has rarely been explored empirically. Our study assesses the influence of homegarden agrobiodiversity, production system parameters, and socioeconomic factors on household dietary diversity and anthropometric conditions in southwest Uganda. Plant inventories of 102 homegardens were followed by two 24-h recalls (n = 589) and anthropometric measurements (n = 325) of household members, as well as household food insecurity questionnaires (n = 95). Regression models explained between 16 and 50% of variance in dietary diversity and between 21 and 75% in anthropometric measurements. Results indicate that supporting diverse homegarden systems can in part reduce food insecurity in Uganda. We conclude with recommendations for further strengthening the role of homegardens in improving dietary and anthropometric outcomes.