http://197.159.135.214/jspui/handle/123456789/957 Thu, 06 Aug 2026 04:29:14 GMT 2026-08-06T04:29:14Z http://197.159.135.214/jspui/handle/123456789/1293 Improving Small Scale Farmers Resilience to Climate Change: Socioeconomic Impacts, Sustainable Systems, and Technological Innovation in Niger and Mali Maman Bizo, Issiaka Climate change is recognized as one of the global challenges affecting agricultural productivity and food security. In Sahel, agriculture is sensitive to climatic hazards. This research aims to provide a comprehensive analysis of the impact of climate change on agricultural yields, the efficiency of climate information systems at the small-scale farmers’ level, the sustainability of millet intensification options, and barriers and enablers of climate-smart agriculture. We obtained meteorological data from national meteorological agency and agricultural yield data from ministry of agriculture. We characterize climate parameters (temperature, precipitation, length of dry spells…). A principal component analysis determined the relationship between climate parameters and agricultural yield and field survey comparesd long term climatic data and farmers’ perception. For rainfall forecasts and alerts, we collected the 2022 data from the ‘SMS Sandji’ platform in Mali (Nara) and the national meteorological agency alert database in Niger (Zinder). We also conducted field suvey to evaluate socio-economic impact of the use of climate information system. The results obtained indicate a concordance between farmers’ perception on climate change and meteorological observations concerning the irregularities of rainfall (83.3% of respondents) except in Zinder where meteorological data shows an increase in rainfall (+122mm), the increase of maximum and minimum temperature (+1.01˚C in Maradi, +0.75 ˚C in Zinder, +0.85 ˚C in Diffa; 90% of respondents), and the delay on rainy season onset (97%) over the past 40 years. Both seasonal and daily climate forecasts have high to moderate accuracy from 0.7 to 0.58 for CSI and 0.11 to 0.43 for BS index in Niger, and 0.94 to 0.91 for CSI, and 0.06 to 0.25 for BS in Mali. ANOVA also reveals with high significance (p value=0.0001) that the utilization of climate information plays a crucial role in improving farmers’ average financial incomes with FCFA 24,943 per hectare at season onset to FCFA 15,355 per hectare during the cropping season, and FCFA 6204 per hectare at the end of the season, depending on the period when the information was used. The System Intensification Analysis Framework reveals that the system combining direct sowing mode with mineral fertilizer micro-dosing, and the one with organic micro-dosing show the best performance regarding almost all sustainability indicators. Farmers have adopted measures to strengthen resilience of their farming systems such as the farmers-managed natural regeneration (88.5%), the use of improved varieties (84.6%), integrated soil fertility management options (75.9%), irrigation (41.7%), and reforestation (37.9%). The findings of this research contribute to the broader understanding of climate change impacts and agriculture in Sahel. A thesis, in the Rural Polytechnic Institute of Training and Applied Research (IPR/IFRA) in partnership with the West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL), submitted in partial fulfilment of the requirements for the Doctor of Philosophy in Climate Change and Agriculture of the University of Sciences, Techniques and Technologies of Bamako (USTTB) Sat, 06 Dec 2025 00:00:00 GMT http://197.159.135.214/jspui/handle/123456789/1293 2025-12-06T00:00:00Z http://197.159.135.214/jspui/handle/123456789/1292 Modeling Climate Risk and Adaptation Strategies for Pearl Millet (Pennisetum glaucum (L.) R. Br.) Production in Senegal Using DSSAT Zagre, Inoussa This thesis explores how climate-smart technologies (CSTs) can enhance the resilience of dryland agricultural systems in Senegal, improving sustainability, productivity, and smallholder farmer incomes. It aims to generate science-based knowledge on climate-smart management practices for pearl millet production in Sub-Saharan Africa through experimentation, modeling, and participatory extension approaches (PREA). The study focuses on four key areas: first, examining the role of socioeconomic and institutional support in shaping community responses across three climate zones in Senegal; second, assessing the performance of micro-dosing fertilization strategies and plant populations on pearl millet production; third, evaluating the DSSAT model’s ability to simulate the response of millet varieties to these strategies; and fourth, predicting millet yields under different fertilization and planting densities scenarios in Senegal’s agroecological zones (AEZs) under current and future climate. Results show that most farmers recognize climate threats, with significant impacts from seasonal rainfall deficits (72%), delayed rainfall onset (88%), frequent dry spells (68%), and prolonged droughts (76%). Key drivers of CST adoption include access to credit, extension services, government subsidies, and advisor interactions, providing valuable insights for resilience-building strategies. The findings highlight that organo-mineral micro-dosing fertilizer (combining Senegal’s recommended mineral rate with 2.5 tons of organic manure), improved plant populations (25,000 hills/ha), and dual-purpose millet varieties consistently enhance yields across study areas. Long-term simulations confirmed these parameters’ effectiveness under both current and future climates. The CERES-Millet model accurately simulated four millet cultivars (Souna 3, SL 28, SL 423, and Thialack-2) with acceptable statistical index values. Future climate projection showed a decrease in rainfall across AEZs (up to 25%) and an increase in minimum and maximum temperatures for the mid-century. The results emphasized that using Senegal's recommended mineral fertilizer rate alone is more sensitive to future climate change, with yield declines ranging from 4% to 16% under SSP2–4.5 and from 8% to 33% under SSP5–8.5 by mid-century compared to organo-mineral doses. Higher planting densities were less sensitive to adverse climate impacts, demonstrating improved resource use efficiency and water retention compared to low-density practices, which exhibited a higher yield decline. Simulations indicate 6–17% yield increases compared to local varieties under various climate projections across AEZs. The effectiveness of interventions varies spatially, with northern regions showing higher vulnerability. Dual-purpose varieties, while effective under current conditions, are expected to decline by 1% to 13% under SSP2–4.5 and 6% to 27% under SSP5–8.5 in the future. These findings underscore the role of integrated soil fertility management (ISFM) and optimal plant density in mitigating climate effects. Smallholder farmers could adopt ISFM to enhance organic manure application combined with mineral fertilizers for sustainable productivity. This study highlights the importance of integrating high-resolution climate projections with agronomic modeling to guide adaptation strategies. A thesis, in the Rural Polytechnic Institute of Training and Applied Research (IPR/IFRA) in partnership with the West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL), submitted in partial fulfilment of the requirements for the Doctor of Philosophy in Climate Change and Agriculture of the University of Sciences, Techniques and Technologies of Bamako (USTTB) Wed, 30 Apr 2025 00:00:00 GMT http://197.159.135.214/jspui/handle/123456789/1292 2025-04-30T00:00:00Z http://197.159.135.214/jspui/handle/123456789/1291 Assessing the potential of biochar to enhance maize productivity and soil organic carbon sequestration under future climate scenarios in Togo Aziandeke, Dodji Ensuring food security has become a major challenge in the face of climate change impacts on agricultural systems, leading to soil fertility decline and reduced crop yields. To investigate the potential of biochar, three field experiments were conducted from July 2022 to January 2024 at the research station of the Togolese Institute for Agronomic Research, the Center of Agronomic Research of the Littoral (ITRA/CRAL) based in Davié across three growing seasons. To leverage our analysis, we used the data to calibrate and evaluate a process-based crop model (DSSAT-Ceres) and applied it to estimate the implications of biochar use under future climate projections. The application of 20 t ha-1 of biochar (B20) significantly increased SOC concentration by 2.20 g kg-1. Meanwhile, B10 and C1 did not significantly influence SOC. The effect on soil total nitrogen from different treatments was not significant. Grain yield increased significantly with biochar application at a rate of 20 t ha⁻¹ during the second season, while the positive effect was marginal in the third growing season. After calibration, the DSSAT-Ceres model showed an RMSE of 0.16% and 0.09%for biomass and SOC, respectively. The future projections at the Davié site showed an increase in temperature of 1.27°C equivalent to 4.58% under the optimistic scenario (SSP126) and 2.05°C which is equivalent to 7.38% under the pessimistic scenario (SSP585) across almost all the 5 GCMs selected in this study, but a +6.67 mm increase under the SSP126 scenario and -12.99 mm decrease in rainfall. If crop management remains the same, maize yields are projected to decrease by 0.84% to 13.03% under the optimistic and 9.05% to 24.11% under the pessimistic scenarios for the years 2040-2070. However, this was not statistically significant. Similarly, the SOC is projected to decrease by 0.11% to 3.47% under the optimistic scenario (SSP126) and decrease by 0.89% to 5.26% under the pessimistic scenario (SSP585). When biochar is integrated as management practice (C0F0B20), the yields and SOC could be increased by 374.38 % and 73.38 %, respectively, as compared to low-input practice (e.g., C0F0B0) in average for historical and future scenarios. If combined with compost and mineral fertilizers, the increase in yield and SOC is higher (483.98 and 80.82%) as compared to low-input, but when compared to C1F1B0 the effect on yields is small (12.83%) whereas SOC increases considerably (20.54%). The model should be improved to capture the management practices and residual effects of soil organic amendments to give a representation close to reality. A thesis, in the Rural Polytechnic Institute of Training and Applied Research (IPR/IFRA) in partnership with the West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL), submitted in partial fulfilment of the requirements for the Doctor of Philosophy in Climate Change and Agriculture of the University of Sciences, Techniques and Technologies of Bamako (USTTB) Sun, 01 Jun 2025 00:00:00 GMT http://197.159.135.214/jspui/handle/123456789/1291 2025-06-01T00:00:00Z http://197.159.135.214/jspui/handle/123456789/1290 Agroecosystem Resilience and Sustainability of Inland Valleys to Climate Change in West Africa: Benin’s Sudano-Guinean and Guinean Zones Case Akodekou, Abiola David Inland valleys (IVs) are critical socio-agroecological systems in Sub-Saharan Africa, providing essential ecosystem services (ES) such as provisioning, regulating, supporting, and cultural services. However, these ecosystems face increasing threats from climatic hazards and anthropogenic pressures, undermining their sustainability and crop productivity. This doctoral research investigates the pathways for conserving and optimizing the ecosystem services of Inland valleys in Benin, focusing on the interplay between management approaches, climatic hazards, and smallholder farmers' adaptive strategies. The study employs a mixed-method approach, integrating quantitative and qualitative data from 298 farmers across 41 Inland valleys, as well as biophysical, climatic (1991–2021), socio-economic data from 76 Inland valleys and an agricultural experiment highlighting the smart and undeveloped valley approach, fertilization levels based on RiceAdvicce technology and the standard level of farmers during 2022 and 2023 in Benin's Guinean and Sudano-Guinean zones. The study addresses four specific objectives. First, it analyses the state of ES provided by Inland valleys under different management approaches, identifying Smart Valley as the most effective in delivering provisioning, regulating, and supporting services (with a relative importance index of 0.85, 0.81, and 0.68, respectively), while undeveloped valleys excel in cultural services (with a relative importance index of 0.45). Second, it assesses the vulnerability of Inland valleys to climatic hazards, revealing that drought affects 35% of Inland valleys, primarily in the Sudano-Guinean zone, and is predicted by soil organic carbon, sand content, and the Standardized Precipitation Evapotranspiration Index (SPEI). Flooding affecting 30% of Inland valleys, is more frequent in the Guinean zone and linked to annual rainfall, sand content, and SPEI. Third, it evaluates smallholder farmers' mitigation strategies, highlighting practices such as organic farming, irrigation, and agroforestry for drought, and crop season adjustments and natural fallow use for flooding. These strategies are influenced by market access, extension services, and infrastructure. Fourth, it assesses the impact of management approaches on sustainability and productivity, demonstrating that Smart Valley approaches significantly improve soil moisture (8.62% higher than undeveloped approaches) and rice yields (35.42% higher), with fertilization further enhancing productivity by up to 13.65%. This research provides actionable insights for policymakers and practitioners to promote the sustainable management of Inland valleys, ensuring their resilience and productivity in the face of climate change and anthropogenic pressures. A thesis, in the Rural Polytechnic Institute of Training and Applied Research (IPR/IFRA) in partnership with the West African Science Service Centre on Climate Change and Adapted Land Use (WASCAL), submitted in partial fulfilment of the requirements for the Doctor of Philosophy in Climate Change and Agriculture of the University of Sciences, Techniques and Technologies of Bamako (USTTB) Tue, 01 Apr 2025 00:00:00 GMT http://197.159.135.214/jspui/handle/123456789/1290 2025-04-01T00:00:00Z