Water yield estimation and sedimentation control in two Volta sub-basins: tools towards integrated water resources management

Small reservoirs form a major source of water supply in the Volta basin. However, sedimentation of reservoirs poses serious threats to overall water yield and storage, consequently impacting community water supplies and livelihoods. This study will assess basin-level water yields and sediment inflow deposited in reservoirs in two Volta sub-basins using the WEAP and SWAT models in combination with spatial analysis techniques. The WEAP Model will assess water allocations while the SWAT model will compute water balance, runoff and sediment yields. Ancillary measured sediment yield data will be used in combination with terrain-based distributed models in a GIS to identify and predict major areas of erosion in the two study sites. Social and biophysical dynamics will be concomittantly assessed through a multi-agent modeling framework (ComMod). To this end, the WEAP and SWAT models will be linked to the computer simulation tool of the ComMod platform. This will allow for assessing the consequences of local practices -and possibly proposed intervention- in terms of erosion (see figure). The results and the approach can be used as decision-support tools to identify practical IWRM interventions that reduce erosion e.g. vegetation strip-ways. It is anticipated that this will result in improved water resources management and reduce impacts of drought spell shocks on the affected communities and could be replicated elsewhere in the Volta basin. (Texte intégral

The impact of financial technology on loan risk and payment systems: evidence from Africa

Fintech can disrupt the delivery of traditional financial services but can equally improve banking for the poor and has the potential to provide new solutions to old problems. Further, signalling theory provides a firm ground to understand how signals can be used by lenders to screen for quality borrowers, reduce uncertainty and facilitate lending. Particularly to informationally opaque borrowers in developing countries. My thesis proposes a model to screen loan applicants based on clients’ adoption of financial technology. Using machine learning algorithms, my results show that, adopters of Fintech are associated with lower default likelihood. I find asymmetric relationship between new and repeat borrowers who adopt Fintech and loan spread. However, clients with bank account only are more likely to default compared to those who adopt Fintech and have bank account. This suggest that Fintech can unlock opportunities for adopters to improve their credit score by linking their Fintech account to their respective bank accounts. Further, over the past decade, payments using Fintech has become critical to the financial systems in most countries in Sub-Saharan Africa. In the third chapter of my thesis, I empirically investigate the impact of the use of financial technology on the payments systems in Africa, financial inclusion and signiorage. Using the VAR-VEC model, my results show that Fintech provides financial inclusion. A variance decomposition analysis show that majority of the forecast error variance is due to own shock. Further, my results show a long-run causal relation between mobile money and payment system transaction, and the use of currency. This confirm that Fintech, can transfer informal cash to the formal banking system and lead to a significant reduction in the social burden of signiorage. The final chapter of my thesis investigate the impact of borrowers’ self-declared religiosity and religious connectedness on loan risk. Using a credit scoring algorithm, I find a significant reduction in default probabilities when borrowers signal as trustable to lenders via their voluntary self-declared religiosity. Further, I find that, all things being equal, borrowers who voluntarily self-declare their religiosity to signal their credit risk are likely to be charged higher interest rate. However, those who self-declare their religious connectedness are associated with the likelihood of receiving lower interest rate, and female borrowers who signal their credit by self-declaring their religiosity are associated with lower default likelihood

Impacts of Climate Change on Stream Inflows into the Volta Lake

The study examined the impact of climate change on future water availability in the Volta Lake from climate downscaled data using ensemble projections of two Global Climate Models (MPEH5 and HADCM3) and two emission scenarios (A1B and A2) used in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. The SWAT hydrological model was calibrated and validated and then used with the downscaled climate change data to assess the impacts of climate change on the inflows to the Lake. Results from the impact assessment showed that future mean annual streamflow into the Volta Lake could increase by about 17 and 16 percent under the A1B and A2 scenarios, respectively. However, streamflow from Geoere, Boromo and Dapola in the Black Volta basin and Nawuni in the White Volta basin could decrease. The projected increase in total annual streamflow in the basin is consistent with the increase in annual rainfall in the basin under both the A1B and A2 scenarios of between 2.0 and 8.0 percent obtained in a separate climate downscaling study. Since streamflow in some of the sub-basins were found to decrease under the climate change scenarios investigated, integrated and prudent management of the basin's water resources would be necessary to ensure sustainability in water use

Environmental sanitation and urban agriculture in Ghana

Environmental sanitation and urban agriculture in Ghan

Agro-climatic and hydrological characterization of selected watersheds in northern Ghana

United States Agency for International Developmen

Integrating GIS and remote sensing for land use/land cover mapping and groundwater potential assessment for climate-smart cocoa irrigation in Ghana.

Although Ghana is a leading global cocoa producer, its production and yield have experienced declines in recent years due to various factors, including long-term climate change such as increasing temperatures and changing rainfall patterns, as well as drought events. With the increasing exposure of cocoa-producing regions to extreme weather events, the vulnerability of cocoa production is also expected to rise. Supplemental irrigation for cocoa farmers has emerged as a viable adaptation strategy to ensure a consistent water supply and enhance yield. However, understanding the potential for surface and groundwater irrigation in the cocoa-growing belt remains limited. Consequently, this study aims to provide decision-support maps for surface and groundwater irrigation potential to aid planning and investment in climate-smart cocoa irrigation. Utilizing state-of-the-art geospatial and remote sensing tools, data, and methods, alongside in-situ groundwater data, we assess the irrigation potential within Ghana's cocoa-growing areas. Our analysis identified a total area of 22,126 km2 for cocoa plantations and 125.2 km2 for surface water bodies within the cocoa-growing regions. The multi-criteria analysis (MCA) revealed that approximately 80% of the study area exhibits moderate to very high groundwater availability potential. Comparing the MCA output with existing borehole locations demonstrated a reasonable correlation, with about 80% of existing boreholes located in areas with moderate to very high potential. Boreholes in very high potential areas had the highest mean yield of 90.7 l/min, while those in low groundwater availability potential areas registered the lowest mean yield of 58.2 l/min. Our study offers a comprehensive evaluation of water storage components and their implications for cocoa irrigation in Ghana. While groundwater availability shows a generally positive trend, soil moisture and surface water have been declining, particularly in the last decade. These findings underline the need for climate-smart cocoa irrigation strategies that make use of abundant groundwater resources during deficit periods. A balanced conjunctive use of surface and groundwater resources could thus serve as a sustainable solution for maintaining cocoa production in the face of climate change

Water balance components estimation under scenarios of land cover change in the Vea Catchment, West Africa

The need for a detailed investigation of the Vea catchment water balance components cannot be overemphasized due to its accelerated land cover dynamics and its associated impacts on the hydrological processes. This study assessed the possible consequences of land use change scenarios (i.e. business as usual (BAU) and afforestation, for the year 2025) compared to 2016 baseline, on the Vea catchment’s water balance components using the Soil and Water Assessment Tool (SWAT) model. The data used include daily climate and discharge, soil and land use/land cover maps. The results indicate that the mean annual water yield may increase by 9.1% under BAU scenario, but decrease by 2.7% under afforestation scenario. Actual evapotranspiration would decrease under BAU scenario but increase under afforestation scenario. Groundwater recharge may increase under both scenarios, but more pronounced under the afforestation scenario. These outcomes highlight the significance of land cover dynamics in water resource management and planning at the catchment

Designing a combined Liothyronine (LT3), L-thyroxine (LT4) trial in symptomatic hypothyroid subjects on LT4 – the importance of patient selection, choice of LT3 and trial design

Approximately 10%–15% of subjects with hypothyroidism on L-thyroxine (LT4) alone have persistent symptoms affecting their quality of life (QoL). Although the cause is unclear, there is evidence that “tissue T3 lack” may be responsible. If so, combining liothyronine (LT3) with LT4 would be helpful. However, randomized controlled trials (RCT), have not established greater efficacy for the LT3 + LT4 combination in these subjects than for LT4 alone. While the trial design may have been responsible, the use of unphysiological, short-acting LT3 preparations and non-thyroid-specific patient-reported outcome measures (PROMs) may have contributed. We recommend attention to the following aspects of trial design for future RCTs of LT3 + LT4 compared to LT4 alone: (a) Subject selection—(i) measurable symptoms (disadvantages should be recognized); (ii) using a validated thyroid specific PROM such as ThyPRO39 or the Composite scale derived from it; (iii) those taking over 1.2 μg/day or 100 μg/day (for pragmatic reasons) of LT4 defining a population likely without intrinsic thyroid activity who depend on exogenous LT4; (iv) recruiting a preponderance of subjects with autoimmune thyroiditis increasing generalisability; and (v) those with a high symptom load with a greater response to combination therapy e.g. those with the deiodinase 2 polymorphism. (b) The use of physiological LT3 preparations producing pharmacokinetic similarities to T3 profiles in unaffected subjects: two long-acting LT3 preparations are currently available and must be tested in phase 2b/3 RCTs. (c) The superiority of a crossover design in limiting numbers and costs while maintaining statistical power and ensuring that all subjects experienced the investigative medication

Empowering citizen-led adaptation to systemic climate change risks

The increasing impacts of climate change instigate the need for adaptation. However, most adaptation initiatives focus on actions by government or businesses, despite growing calls for communities on the frontline of climate risks to be involved in planning and selecting strategies. Here, we appraise a pilot process using participatory systems mapping with citizens to identify 1) diverse threat vectors for local climate impacts and 2) context-relevant interventions to protect households and communities while 3) considering synergies and tradeoffs with other socially desirable outcomes. We tested the pilot process in communities in the lower Volta Basin in Ghana, the Assam region in India, and Southern England. From participants' perspectives, the process increased awareness of- and preparedness for climate change impacts and raised essential learning points for upscaling citizen-led adaptation approaches. These include understanding multiple outcomes of interventions, barriers, and enablers to implementation, and sensitivity of co-design to regional geography and socio-cultural context