Sahel Research Articles

Teaching and teachers in the Sahel countries by 2030: The need to innovate in the face of adversity

AbstractThis article examines the educational and teacher-related policies in the Sahel region countries over the past decade and highlights main issues that hinder their ability to achieve the Sustainable Development Goals by 2030. The discrepancy between the current situation and the desired pace of change can be attributed to the lack of prioritization in educational and teaching policies. This article proposes an alternative approach, emphasizing the selection of a maximum of five objectives and providing the necessary means for their effective implementation. By adopting a focused approach, the Sahel region can make strides in overcoming educational challenges and aligning with the goals set for 2030.

Recent advances in cowpea IPM in West Africa

Cowpea is an important and climate-resilient grain legume for human and livestock nutrition worldwide. Its grains represent a valuable source of protein for rural families in Sub-Saharan Africa while its haulms offer nutritious fodder for livestock, especially, in the Sahel regions. Cowpea production, unfortunately, faces substantial challenges of field and storage insect pests which can cause up to 100% losses. The use of synthetic pesticides, although providing farmers with a good level of pest control, has underscored the critical need for the development of integrated pest management (IPM) alternatives, due to their detrimental effects on humans, animals and the environment. This review examines recent advances in West Africa in cowpea IPM approaches, highlighting research on host plant resistance, biological control, biopesticides, good cultural practices, and on-farm participatory research and training undertaken to support sustainable cowpea production. Numerous IPM options have been developed, tested and validated for combating cowpea insect problems in West Africa by research institutions and disseminated through farmer field schools (FFS), field demonstrations, training sessions, and community-based education. Reviewing these environmentally safer and scalable IPM innovations will provide cowpea stakeholders with insights into workable, sustainable solutions for minimizing crop pest problems, reducing reliance on harmful pesticides and ultimately ensuring the long-term viability of cowpea production and its contribution to food security.

Proactive policy options for drought resilience in the Sahel region

In the Sahel region, drought is of serious concern due to its consequences on the livelihoods of the populations. In this paper, opportunities for proactive drought policies are analyzed with qualitative techniques using a series of semi-structured qualitative interviews with key experts from the public, private, and other relevant societal sectors. The results show that adaptation options such as sustainable agricultural practices, migration, diversification of income sources, and social networks are most frequently used as a drought response by rural households in the region. To build resilience to drought in the Sahel, there is a need to disseminate climate-friendly agricultural practices accompanied by strong monitoring and evaluation system. It is also important to provide information on early drought warning and preparedness and mobilize more financial resources in implementing policies for building drought resilience. Finally, a drought policy should be participatory and results-based, and be based on long-term forecasting to ensure sustainability and resilience.

Burning questions: Experiments on the effects of charring on domestic and wild sorghum

Sorghum was first domesticated approximately 6000 years ago in the eastern Sahel region of Africa, but our understanding of its agricultural history is uneven due to the paucity of the available archaeobotanical evidence. Despite growing interest in the issue, sorghum response to fire exposure has been little investigated. In this paper, the resistance of six domesticated sorghum varieties (Sorghum bicolor) and one wild specimen (Sorghum arundinaceum) to charring was evaluated under oxidising and reduced oxygen conditions using temperatures ranging from 300 °C to 500 °C for 1–8 h. The experimental study in this work indicates that the maximum temperature wild sorghum can resist without severe distortion is around 300 °C, whereas domesticated varieties could resist up to 350 °C before becoming damaged beyond identification. Our findings suggest that resistance to temperature might represent an important bias for sorghum seed preservation, both in its wild and domesticated forms.

Investigation of the Earth’s Albedo using Meteorological Parameters over Nguru, Nigeria

Estimation and investigation of an earth’s albedo is significant in the evaluation and design of solar energy collectors, atmospheric radiative transfer and studies that relates to atmospheric thermal balance. This study employed the shortwave solar energy balancing at the edge of the Earth’s atmosphere to estimate and compare the variation of albedo for Nguru situated in the Sahelian region of Nigeria, using measured monthly mean daily meteorological parameter of global solar radiation obtained from the National Aeronautics and Space Administration (NASA) during the period of thirty-eight years (1984 – 2021). The variation of albedo with surface temperature, maximum wavelength, clearness index, global solar radiation, relative humidity and mean temperature for this location was investigated. The results in this study show that the estimated surface albedo depicts a direct opposite relationship with the clearness index, an inverse relationship with the emitting Earth’s surface temperature and a direct relationship with the wavelength for the studied location. The highest and lowest values of albedo for the location was in the months of August and January with 0.4628 and 0.3403 respectively. The emitting Earth surface temperature ranged between 238.5837 K in August and 251.1607 K in January. These values agreed closely to the standard emitting Earth surface temperature value (255.0000 K). The maximum emitting wavelength values for the location revealed that the radiation is longwave and is found within the infrared region of the electromagnetic spectrum.

Learning from history of natural disasters in the Sahel: a comprehensive analysis and lessons for future resilience.

One of the first environmental crises to attract interest in development initiatives and aid was the great drought of the 1970s in the Sahel. This study investigates the extent of damage caused by natural disasters from one of the most widely used databases-EM-DAT-with a sample size of 16 Sahelian countries over the period 1960-2020. These countries have been divided into three regions: Western Africa Sahel (WAS), Central Africa Sahel (CAS), and Eastern Africa Sahel (EAS). The analyses encompass four categories of natural hazards, namely, biological, climatological, hydrological, and meteorological. We used descriptive and test statistics to summarize the natural disaster records. Through this approach, we explore tendencies to identify the most frequently reported natural hazards; we examine their spatial distribution and evaluate their impacts in terms of socioeconomic damage and causalities. During the study period, a total of 1000 events were recorded in the database. The Western Africa Sahel (WAS) region had the highest number of disasters, with 476 events, followed by the Eastern Africa Sahel (EAS) region with 369 events. The most common hazards in the Sahel were hydrological (41.8%), mainly floods, and biological (39.5%) hazards. Approximately 300 million people in the Sahel were affected by natural hazards, with 59.17% in EAS, 36.48% in WAS, and 4.35% in CAS. Although droughts occurred less frequently (14%), they had a significant impact on the population, affecting 84% of those affected by natural hazards. In general, EAS experiences a higher impact from natural hazards, potentially influenced by the pastoral lifestyle of its population. However, WAS is also very vulnerable to natural hazards especially epidemics and nowadays floods. The uncontrolled urbanization in the area may contribute to this vulnerability.

Diversification of Livelihoods as an Adaptive Response to Climate Change Impacts in Mali's Sahel Region: Case of Diema Circle

Diversification of Livelihoods as an Adaptive Response to Climate Change Impacts in Mali's Sahel Region: Case of Diema Circle

Groundwater quality assessment for sustainable irrigation in Nanton district, Ghana

Abstract As part of the semi-arid region, Ghana falls within the West African Sahel region with high climatic variability and severe droughts, especially in the Northern parts. The Northern region is characterized as one of the driest in Ghana. It experiences one rainy season in a year, though agriculture is one of the main economic activities. Nanton district in the Northern region consists of farming communities. However, there is limited availability of water for crop watering during the dry season and groundwater could become a possible source of water supply. This research, therefore, seeks to provide information on the irrigation quality status of groundwater in the Nanton district. Information from this research also aims to assist policymakers take the right decisions for sustainable agriculture in the study area. Irrigation water indexes in combination with the USSL diagram were adopted as methods for analyses in this research. Results generally suggest that groundwater in the study area is suitable for irrigation purposes, except for a few places in the district. Further studies should be conducted to precisely state the quality of water used for drinking and domestic purposes. The research should also emphasize identifying factors controlling groundwater chemistry in the area.

Influence of Solid Retention Time on Membrane Fouling and Biogas Recovery in Anerobic Membrane Bioreactor Treating Sugarcane Industry Wastewater in Sahelian Climate.

Sugarcane industries produce wastewater loaded with various pollutants. For reuse of treated wastewater and valorization of biogas in a Sahelian climatic context, the performance of an anaerobic membrane bioreactor was studied for two solid retention times (40 days and infinity). The pilot was fed with real wastewater from a sugarcane operation with an organic load ranging from 15 to 22 gCOD/L/d for 353 days. The temperature in the reactor was maintained at 35 °C. Acclimatization was the first stage during which suspended solids (SS) and volatile suspended solids (VSS) evolved from 9 to 13 g/L and from 5 to 10 g/L respectively, with a VSS/SS ratio of about 80%. While operating the pilot at a solid retention time (SRT) of 40 days, the chemical oxygen demand (COD) removal efficiency reached 85%, and the (VSS)/(TSS) ratio was 94% in the reactor. At infinity solid retention time, these values were 96% and 80%, respectively. The 40-day solid retention time resulted in a change in transmembrane pressure (TMP) from 0.0812 to 2.18 bar, with a maximum methane production of 0.21 L/gCOD removed. These values are lower than those observed at an infinite solid retention time, at which the maximum methane production of 0.29 L/gCOD was achieved, with a corresponding transmembrane pressure variation of up to 3.1 bar. At a shorter solid retention time, the fouling seemed to decrease with biogas production. However, we note interesting retention rates of over 95% for turbidity.

Beyond the numbers: An in-depth look at Cameroon's fifth national COVID-19 vaccination campaign through geographical and gender lenses

BackgroundCameroon has been struggling with low Covid-19 vaccination coverage, with only 4.5 % of the population receiving the primary series as of November 2022. The COVID-19 Vaccine Delivery Partnership (CoVDP) conducted a high-level mission to Cameroon to assess progress and advocate for actions to address bottlenecks. The objective of the mission was to administer at least 3,000,000 doses of vaccines during the 5th Mass vaccination campaign. This study examines the factors contributing to the success of the campaign and uses a geographical and gender lens to assess the results. MethodsThe study is a secondary analysis of data from the DHIS2 collected during the 5th mass vaccination campaign for Covid-19. Descriptive statistics were used to assess coverages per location and gender expressed in OR. sccess factors, and chi-squared tests were used to assess differences in vaccine distribution across regions and by gender. ResultsThis 5th vaccination campaign benefitted from a strong political commitment facilitated by CoVDP's mission, international support, collaboration, planning, supervision, and demand generation.The campaign recorded 2 019 118 administered vaccine doses, a staggering 46-fold increase in vaccinated individuals relative to the first round, with vaccination coverage reaching 10.1 % of the general population. However, the study reveals regional and gender disparities in vaccination coverage. Men had higher odds of being vaccinated than women in the three Sahel regions. Among individuals with comorbidities, the national coverage rate was only 14 %, and the Far North and East regions exhibited the lowest coverage rates. Janssen was the most used vaccine, and the total AEFI cases reported were 2 per 1000 vaccine doses. ConclusionThe 5th COVID-19 vaccination campaign in Cameroon saw a strong political commitment and was the most successful so far. Despite the gains, there was gender disparity in coverage in some regions. It is important to continue the established momentum, ensure equitable access in the Sahel regions, and reach high-priority groups with primary series and booster doses.

Characterization of Vulnerability of Internally Displaced Persons in Burkina Faso, Mali, and Niger Using Respondent-Driven Sampling (RDS)

Abstract The Central Sahel region has one of the world's fastest-growing populations of internally displaced persons (IDPs). To better understand the risk factors associated with displacement, this study utilized respondent-driven sampling to recruit otherwise hard-to-reach IDPs in remote and urban areas in Burkina Faso, Mali, and Niger. From August to October 2021, 4144 IDPs were surveyed, and nine targeted vulnerability profiles were measured across the domains of gender, health, and protection. The study revealed a high prevalence of risk factors and vulnerability among IDPs, with notable geographic differences. The majority of IDPs fell into at least one category of vulnerability, with health vulnerabilities being the most common. Internally displaced persons reported overlapping vulnerabilities in health, particularly chronic illness, mental health issues, and disability. Women had higher odds of vulnerability than men. Statistically significant associations were site-specific, and some were inconsistent across contexts, highlighting the cross-cutting and pervasive nature of vulnerability among IDPs.

Trends and impacts of climate change on crop production in Burkina Faso

Abstract Understanding past climate trends and their impacts in the Sahel region is fundamental for climate change (CC) adaptation and mitigation. This study analyses climate trends from 1961 to 2020 in three climatic zones in Burkina Faso and the impacts of CC on five major crops production. Long time series of daily rainfall and temperature data from National Meteorology Agency for the period 1961 to 2020 has been compiled. Crop production data (1984–2020) were retrieved from the agriculture department. Climate temporal variations in each climatic zone were analyzed using extreme climate indices and principal component analysis. Linear regression was used to assess climate impacts on crop production. The results showed a high rainfall variability and changes in temperature extremes in the three zones. The climate window, 1991–2020, was hotter than 1961–1990, while the last decade (2011–2020) was the wettest. Most climate indices (67%) showed significant correlations with crop yields. Dry spells, cool days, cold nights, average daily wet days and rainfall intensity showed positive and negative effects on maize, cowpea, millet and sorghum yields. This study highlights the importance of climate-smart policy promoting drought-resistant and short-duration varieties in addressing the adverse effects of CC on crop production.

Drought vulnerability of central Sahel agrosystems: a modelling-approach based on magnitudes of changes and machine learning techniques

ABSTRACT Agricultural drought is a complex phenomenon with numerous consequences and negative implications for agriculture and food systems. The Sahel is frequently affected by severe droughts, leading to significant losses in agricultural yields. Consequently, assessing vulnerability to agricultural drought is essential for strengthening early warning systems. The aim of this study is to develop a new multivariate agricultural drought vulnerability index (MADVI) that combines static and dynamic factors extracted from satellite data. First, pixel temporal regression from 1981 to 2021 was applied to climatic and biophysical covariates to determine the gradients of trend magnitudes. Second, principal component analysis was applied to groups of factors that indicate the same type of vulnerability to configure the basic equation of vulnerability to agricultural drought. Then, random forest (RF), K-nearest neighbours (KNN), support vector machine (SVM) and naïve Bayes (NB) were used to predict drought vulnerability classes using the 28 factors as inputs and 708 pts of randomly distributed class labels. The results showed statistical agreement between the predicted MADVI spatial variability and the reference model (R=0.86 for RF) and its statistical relationships with the vulnerability subcomponents, with an R=0.73 with exposure to climate risk, R=0.64 with the socioeconomic sensitivity index, R=0.6 with the biophysical sensitivity index and a relatively weak correlation (R=0.21) with the physiographic sensitivity index. The overall vulnerability situation in the watershed is 21.8% extreme, 10% very high, 16.8% high, 27.7% moderate, 22.2% low and 1.5% relatively low considering the cartographic results of the predicted vulnerability classes with SVM having the best performance (accuracy=0.96, Kappa=0.95). The study is the first approach that uses the gradients of magnitudes of satellite covariate anomaly trends in multivariate modelling of vulnerability to agricultural drought. It can be easily scaled up across the Sahel region to improve early warning measures related to the impacts of agricultural drought.

The use of explanatory statistics for mapping groundwater potential zones in a semiarid area: Case of the Waddai province, eastern Chad

In Waddaï province, Eastern Chad, the dry tropical climate of the Sahel region causes a scarcity of surface water resources in the area. To respond to the growing demand on this vital element, and to preserve the social, economic and political stability, several groundwater (GW) exploration programs have been conducted in the previous decades. Of the few thousands of boreholes executed at the province of Waddaï, most fail to find GW reservoirs due to a lack of GW potential maps. In this study we try to fill this knowledge gap using Frequency Ratio (FR) and Weight of Evidence (WoE) techniques. The position of successful wells was used to train the statistical analysis methods and validate the models, while a total of nine topographic, geological and environmental factors were chosen as predictive variables. Results showed that the Southern and central parts of the province have greater potential for the presence of GW. This disposition was shown to be mainly controlled by lithology and slope, where flat areas dominated by unconsolidated alluvial deposits favour infiltration while rocky steep terrains favour surface flow. In comparison to the only previous study recently published, which used and expert opinion Multi-Criteria Decision-Making and Analytical Hierarchical Process based approach for the same purposes, some contradictions with the FR and WoE were observed in some predictive variable class weights, especially regarding lineament density and drainage density. This shows that, in areas where hydrogeological mechanisms and processes are not well understood, it is risky to rely on theoretical simplifying assumptions which are not always true.

New Challenges for French Foreign Policy in Africa - Focus on the Sahel Region

New Challenges for French Foreign Policy in Africa - Focus on the Sahel Region

Impacts of Mining on the Environment in West African Sahel: A Review

Mining activities have led to the depletion of over 577.15 km² of forest area in the West African Sahel zone. These have destroyed the habitats of mammals, including elephants and giraffes, as well as economic trees and grass species, and polluted ground and surface water. In addition, mining activities are responsible for degrading more than 1,000 acres of farmland. Even though mining is destroying the environment, it has accounted for exports of €211,468,13, €247,034,485 and €275,720,817 in Burkina Faso, Niger, and Mali, respectively, between 2014 and 2015. It is also a lever of sustainable environmental management, as in Senegal, by providing mining social funds for mining communities and employing over 450,000 people in Niger. Furthermore, mining companies promote land restoration activities in the West African Sahel, such as China National Petroleum Corporation (CNPC) promoting tree plantations in Niger. Nevertheless, the mining in the region will continue to serve as the breeding ground for criminal gangs and terrorist groups unless a radical approach stabilises the insecurity. The degradation of farmlands and forest reserves or protected areas requires re-evaluation and full enforcement of the existing laws and regulations to achieve sustainable mining for the needed development in the West African Sahel region.

Promoting private forests for biodiversity conservation and ecosystems restoration in the Sahel region

Private forests have the potential to mitigate biodiversity loss and improve community livelihoods. However, information on the socio-ecological factors that drive their establishment and long-term management are limited. This study aimed to narrow this gap by assessing the potential of privately-owned forests in conserving biodiversity and supporting the livelihoods of communities in northern Burkina Faso. Floristic data were collected within 26 plots (900 m2 each) equally distributed between private Gourga forest, established in 1980) and its adjacent communal areas. Sixty-three (63) private landowners were interviewed in order to underpin their motivations and associated traditional knowledge and a stakeholder’s workshop was conducted to develop conservation models for private forests and participatory implementation roadmap. Findings revealed that species richness was 132 in the Gourga forest and 85 in the communal areas, highlighting the importance of private forest in species conservation. Local communities recognized the provisioning (36.46%), regulating (28.46%) and supporting (22.48%) of ecosystem services provided by the Gourga forest as motivating factors. The main barriers to their establishment and management include lack of financial resources (35%), scarce lands (26%) and human pressures (8%). The implementation of private forests will need to be supported by the enactment of a secure land tenure policy, as well as payment for ecosystem services (PES) policies, incentivizing locals. We suggest decision makers mainstream privately-owned lands into national conservation strategies and design incentives policies to motivate local communities’ engagement.

Hydrological regime of Sahelian small waterbodies from combined Sentinel-2 MSI and Sentinel-3 Synthetic Aperture Radar Altimeter data

Abstract. In the Sahelian semi-arid region, water resources, especially small waterbodies such as ponds, small lakes, and reservoirs in rural areas are of vital importance. However, because of their high number and the scarce in situ monitoring networks, these resources and their spatiotemporal variability are not well known at the regional scale. This study investigates the hydrological regime of 37 small waterbodies, located in Mali, Niger, and Burkina Faso in central Sahel. We propose a method based on remote sensing data only, which consists of combining water height data from Sentinel-3 Synthetic Aperture Radar Altimeter (SRAL) with water area data obtained with the Sentinel-2 MultiSpectral Instrument (MSI) to create a dense water height time series. Water height variations are then compared to the evaporation estimated by the Penman–Monteith method, using ERA5 reanalysis by the European Centre for Medium-Range Weather Forecasts (ECMWF) to infer water regimes during the dry season. Three main regimes stand out, namely a net water loss, mainly resulting from anthropogenic withdrawals, a net water supply occurring after the end of the rainy season through river network or water table exchange, and a balanced behaviour, where water losses during the dry season closely correspond to evaporation rates. Spatial patterns have been identified; in central Burkina Faso, most of the reservoirs show a net dry season water loss, which is explained by frequent irrigation, while reservoirs in northern Burkina Faso, generally show little water loss, indicating that water withdrawal is not significant in this area. Lakes located in the Inner Niger Delta in Mali and connected to the Niger River network generally show an important water supply, particularly at the beginning of the dry season. Lakes in Niger tend to show a weak signal toward water inflow that could be explained by exchange processes with the groundwater. These results show that satellite data are effective at estimating hydrological regimes and the anthropogenic impact on water resources at the large scale, including resources found in small waterbodies.

The case for drones in counter-insurgency operations in West African Sahel

ABSTRACT The security situation in the Sahel region has been deteriorating with a consistent increase in violence. Despite tens of thousands of international troops in the region for over a decade, little headway has been made in establishing government control over the territory. The ongoing multilateral and large-scale military operations in the region have employed a boots-on-the-ground strategy that has been largely ineffective in stamping out the insurgency. The paper advocates for a recalibrated counter-insurgency strategy predicated on drones’ heightened and consistent deployment for counter-insurgency operations in the West African Sahel. This is in response to France's phased withdrawal from the region and the limited effectiveness of current multilateral military endeavours to quell the insurgency. The paper presents two related arguments hinged on the tactical utility of drones, drawing on the concept of ungoverned spaces as a theoretical foundation.

A Security Perspective on Turkey-Africa Relations: Analysis of Smart Power Strategy

Somalia and soft power diplomacy in East Africa has been the first and most important step in Turkey's engagement with the African continent. In this way, with its opening to Africa initiative and investments in Somalia, Turkey has demonstrated to the international community that it will be among the important actors contributing to the future of the African community. Today, starting from East Africa, Turkey has been developing and strengthening its influence and presence in many regions of Africa, including North Africa, Sub-Saharan Africa, and the Sahel Region, through its multidimensional foreign policy. Moreover, it has successfully supported its soft power diplomacy in the continent with its initiatives in the field of the defense industry and its Smart Power strategy and has come to the forefront as a security partner of the African countries.