Sahel Research Articles

Learning from the past to guide the future: a SWOT-AHP analysis of tree-based land restoration endeavours in the Northern Sahel region of Cameroon

This paper analyses restoration efforts in the Northern Sahel region of Cameroon using a combination of SWOT analysis and the Analytical Hierarchical Process approach. Based on the perception of key informants from three stakeholder groups – representatives of the administration, representatives of communities, representatives of local NGOs, the results show that the positive attributes of restoration efforts overshadow the negative aspects. Moreover, source of additional income for families from restoration received the overall highest factor score ranking for strength. Tenure insecurity is the weakness with the highest score and the overall priority score for weaknesses was highest for key informants from local NGOs. On the other hand, improving livelihoods and natural resource base of communities received the highest overall factor for opportunities, while inadequate supply of quality inputs for restoration was perceived as the most critical threat to land restoration efforts in the northern Sahel region of Cameroon.

Boko-Haram insurgency in Borno State and its challenge to the Nigerian Army

The paper describes Islam in the Sahel region, prior to the advent of Usman Dan Fodio, who through Jihad, upset the established Islam and replaced same with a new form of Islam, which was said to be purer. He believed that, the Islamic ideology which had been in place around the Sahel region had been syncretic and should therefore be replaced. It does appear that, this development had formed the foundation for the present puritan struggle, led by the insurgents in the North East of Nigeria, where Islam had initially started off in Nigeria. The paper traces the basic beliefs and teachings of members of the Boko-Haram and their splinter groups, which clearly contradict the known Islamic standards. To this end, members of Boko-Haram had thrown caution to the winds as regards western education. It totally abhors and condemns western education and all its attendant paraphernalia. This belief system has set the extremists in collusion with the law enforcement agencies of Nigeria. The war has dragged on for so long, despite the fact that the leadership of the insurgency had been decimated severally. The lesson learnt has been that it would be very difficult to defeat the insurgents, as they continue to metamorphose and develop into splinter groups. To make the situation worse, the researcher discovered that, the insurgents are now internationally affiliated.

Projections of fire emissions and the consequent impacts on air quality under 1.5 °C and 2 °C global warming

Fire is a major source of atmospheric aerosols and trace gases. Projection of future fire activities is challenging due to the joint impacts of climate, vegetation, and human activities. Here, we project global changes of fire-induced particulate matter smaller than 2.5 μm (PM2.5) and ozone (O3) under 1.5 °C/2 °C warming using a climate-chemistry-vegetation coupled model in combination with site-level and satellite-based observations. Compared to the present day, fire emissions of varied air pollutants increase by 10.0%–15.4% at the 1.5 °C warming period and 15.1%–22.5% at the 2 °C warming period, with the most significant enhancements in Amazon, southern Africa, and boreal Eurasia. The warmer climate promotes fuel dryness and the higher leaf area index increases fuel availability, leading to escalated fire flammability globally. However, moderate declines in fire emissions are predicted over the Sahel region, because the higher population density increases fire suppressions and consequently inhibits fire activities over central Africa. Following the changes in fire emissions, the population-weighted exposure to fire PM2.5 increases by 5.1% under 1.5 °C warming and 13.0% under 2 °C warming. Meanwhile, the exposure to fire O3 enhances by 10.2% and 16.0% in response to global warming of 1.5 °C and 2 °C, respectively. As a result, limiting global temperature increase to 1.5 °C can greatly reduce the risks of exposure to fire-induced air pollution compared to 2 °C.

Mapping of Aquifer Potential in the Northeast Basement Rock of Burkina Faso: Using Remote Sensing and Geophysical Methods

The North-East of Burkina Faso is made up of formations of the Birimian basement rock. The region has a Sahelian climate where surface water resources are very limited. In order to assess the hydraulic potential of the existing aquifers, remote sensing and geophysical techniques (aeromagnetic and ground electric) were used. Satellite image processing and aeromagnetic survey data were used to generate a lineament map that was subsequently validated on the basis of existing geological, hydrogeological and topographical data, geomorphological field surveys and ground geophysical work. The resulting map displays a more or less dense network of 405 magnetic lineaments with a cumulative length of 1,787,676 meters as opposed to 94 lineaments from Landsat 8 images with a cumulative length of 970,054 meters. The average length of the magnetic lineaments is 4,414.01 meters while the average remote sensing length is 10,317.72 meters. The identified NE-SW and WNW-ESE fracture corridors are propitious for the presence of fracture aquifers. In addition to the lineament validation, the ground geophysics performed through electrical surveys allowed the characterization of the aquifers in the study area. Alteration thicknesses are generally less than 20 meters deep. The fractured horizon can reach 100 meters thickness under the alterites. The kernel density map highlights areas of good aquifer potential that could constitute significant groundwater reserves. Mapping aquifer potential is a crucial step in ensuring sustainable and efficient use of groundwater resources.

A Functional Trait-Based Approach to Evaluate the Resilience of Key Ecosystem Functions of Tropical Savannas

The persistence of the woody vegetation of the Sahelian savannas, and their supported ecosystem functions, have been questioned since the great drought of 1970s–1980s. To assess the resilience of this vegetation to drought and grazing, we undertook a trait-based approach using field inventory, historical survey databases, and traits data literature. Using a hierarchical clustering approach, we gathered the species present from 1970 to 2015 into functional groups according to their effect traits related to primary productivity and biogeochemical cycles. First, we studied the evolution of functional redundancy (FRe) and response diversity (RDiv) of the functional effect groups to drought and grazing, two indicators of resilience, since the 1970s. Second, we looked at the spatial variation of these two indices in 2015, according to local topography. FRe and RDiv of 80% of the functional groups examined declined since 1970, endangering the persistence of the studied functions. Local topography strongly influenced current FRe and RDiv, with depressions presenting higher values. Finally, by examining species’ abundances, their regeneration, and the functional group to which they belong, we determined some key species that could benefit from protection to ensure the persistence of the ecosystem functions supported by the woody vegetation. This study has expanded knowledge about the savanna’s response to pressures and has shown how a functional traits-based approach could be an effective tool to guide the management of tropical savannas.

Temporal Relationships Between Saharan Dust Proxies, Climate, and Meningitis in Senegal.

The Harmattan, a dry, northeasterly trade wind, transports large quantities of Saharan dust over the Sahelian region during the dry season (December-March). Studies have shown that bacterial meningitis outbreaks in Sahelian regions show hyper-endemic to endemic levels during high-dust months. We examine the (a) seasonality and intraseasonal variability of dust, climate, and meningitis and the (b) quantitative relationships between various dust proxies with meningitis lags of 0-10weeks in Senegal from 2012 to 2017. The results show that the onset of the meningitis season occurs in February, roughly 2months after the dusty season has begun. The meningitis season peaks at the beginning of April, when northeasterly wind speeds and particulate matter (PM) are relatively high, and the meningitis season ends near the end of June, when temperature and humidity rise and northeasterly wind speeds decline. Furthermore, we find that Senegal's relatively high humidity year-round may help slow the transmission of the infection, contributing to a lower disease incidence than landlocked countries in the meningitis belt. Lastly, our results suggest the desert dust may have a significant impact on the onset to the peak of the meningitis season in Senegal, particularly at the 0-2 and 10-week lag, whether that be directly through biological processes or indirectly through changes in human behavior. PM and visibility, however, are not in phase with aerosol optical depth throughout the year and consequently show different relationships with meningitis. This study further exemplifies the critical need for more PM, meteorological, and meningitis measurements in West Africa to further resolve these relationships.

A Drought Dataset Based on a Composite Index for the Sahelian Climate Zone of Niger

Agricultural drought monitoring in Niger is relevant for the implementation of effective early warning systems and for improving climate change adaptation strategies. However, the scarcity of in situ data hampers an efficient analysis of drought in the country. The present dataset was created for agricultural drought characterization in the Sahelian climate zone of Niger. The dataset comprises the three-month scale and monthly time series of a composite drought index (CDI) and their corresponding drought classes at a spatial resolution of 1 km2 for the period 2000–2020. The CDI was generated from remote sensing data, namely CHIRPS (Climate Hazards Group InfraRed Precipitation with Stations), normalized difference vegetation index (NDVI) and land surface temperature (LST) from MODIS (Moderate Resolution Imaging Spectroradiometer). A weighing technique combining entropy and Euclidian distance was applied in the CDI derivation. From the present dataset, the extraction of the CDI time series can be performed for any location of the study area using its geographic coordinates. Therefore, seasonal drought characteristics, such as onset, end, duration, severity and frequency can be computed from the CDI time series using the theory of runs. The availability of the present dataset is relevant for the socio-economic assessment of drought impacts at small spatial scales, such as district and household level. This dataset is also important for the assessment of drought characteristics in remote areas or areas inaccessible due to civil insecurity in the country as it was entirely generated from remote sensing data. Finally, by including temperature data, the dataset enables drought modelling under global warming.

Prevalence and factors associated with brucellosis and tuberculosis in cattle from extensive husbandry systems in Sahel and Hauts-Bassins regions, Burkina Faso

Brucellosis and tuberculosis are important zoonotic diseases with high economic and public health importance mainly in low income countries. In Burkina Faso, studies have been implemented to assess prevalence of these diseases but data remain scare about the prevalence in extensive husbandry systems. This study aimed to determine the prevalence and factors associated with brucellosis and tuberculosis in cattle from extensive husbandry systems in two regions of Burkina Faso. Serums samples were collected on 2195 cattle from 206 herds in Hauts-Bassins and Sahel region. Intradermal skin test and Rose Bengal Plate test have been carried out for the diagnosis of tuberculosis and brucellosis respectively. The overall herd prevalence was 18.93% and 25.73% respectively for brucellosis and tuberculosis while the herd prevalence of co-infections was 6.31%. The individual prevalence was 3.64% (95% CI: 2.85% - 4.42%) and 3.51% (95% CI: 2.74% - 4.28%) for brucellosis and tuberculosis respectively. A prevalence of 0.32% (95% CI: 0.08% - 0.55%) was noted for co-infections. Brucellosis infection was associated with herd size, animal sex and age (p ˂ 0.05). The highest prevalence was found in herds of more than 60 animals (8.2%; 95% CI: 5.7%-10.6%) and in animal aged between 5 and 8 years old (5.3%; 95 CI: 3.4%–7.1%). The prevalence was significantly higher in females (3.9%; 95%CI: 3.0%–4.7%) compared with males (1.0%; 0.04% - 2%). Tuberculosis prevalence was significantly higher in Hauts-Bassins region (6.2%; 95% CI: 4.4%-8.0%) than in Sahel region (2.3%; 95% CI: 1.5%–3.0%). The highest prevalence of tuberculosis was found in herds with at most 30 animals (9.9%; 95% CI: 4.0% - 15.7%) and in animal less than 4 years old (5.4%; 95% CI: 3.4%–7.4%). Results suggest that brucellosis and tuberculosis are prevalent in cattle herds, therefore management practices are needed for better control of the zoonotic diseases.

Changes in Diurnal Temperature Range Over Nigeria from 1960 to 2019

Diurnal temperature range (DTR) is an important derived variable used in detecting signature of observed climate changes. Understanding its changes in recent time is important for managing and coping with climate change induced risks. This study analysed the long term trend and abrupt changes in diurnal temperature range over Nigeria from 1960 to 2019. Descriptive statistics, Mann-Kendall trend test, Sen’s slope and Pettit’s tests were used to assess the characteristics, trend, abrupt change and significance in annual DTR time series. Pearson correlation was used to examine the spatial relationship between DTR and minimum temperature, maximum temperature, precipitation and cloud cover. Results showed that mean DTR amount varied across spatio-temporal scales with steady increase from the coastal region, coupled with a weak inter-annual variability (CV < 3%). The trend analysis showed a significant decreasing DTR in most grid points (GP) and regions of Nigeria, with the exception of Enugu, Ado-Ekiti and Warri. Also a significant negative trend was observed at the Guinea, Sudan and Sahel savanna regions. Abrupt changes occurred in the 1970s in the entire regions and most of the GPs with Ado-Ekiti, Calabar, and Enugu occurred in 1991 while Maiduguri and Jos experienced such changes in 2011. Furthermore, significant abrupt changes were observed at the following GPs and regions; Ikeja, Kaduna, Kano, Katsina, Sokoto, Yelwa, Yola, Guinea, Sudan and Sahel Savannas. This decrease in DTR over most of the GP and the entire region indicate that the climate of Nigeria is becoming warmer possibly due to environmental changes with precipitation and cloud cover being the major drivers of DTR variability in Nigeria. Thus, proper climate actions should be taken through adaptation and resilient planning for the sustainable development of socio-economic and natural systems.

Assessing impact of agroecological interventions in Niger through remotely sensed changes in vegetation

Water scarcity is a major challenge in the Sahel region of West Africa. Water scarcity in combination with prevalent soil degradation has severely reduced the land productivity in the region. The decrease in resiliency of food security systems of marginalized population has huge societal implications which often leads to mass migrations and conflicts. The U.S. Agency for International Development (USAID) and development organizations have made major investments in the Sahel to improve resilience through land rehabilitation activities in recent years. To help restore degraded lands at the farm level, the World Food Programme (WFP) with assistance from USAID’s Bureau for Humanitarian Assistance supported the construction of water and soil retention structures called half-moons. The vegetation growing in the half-moons is vitally important to increase agricultural productivity and feed animals, a critical element of sustainable food security in the region. This paper investigates the effectiveness of interventions at 18 WFP sites in southern Niger using vegetative greenness observations from the Landsat 7 satellite. The pre - and post-intervention analysis shows that vegetation greenness after the half-moon intervention was nearly 50% higher than in the pre-intervention years. The vegetation in the intervened area was more than 25% greener than the nearby control area. Together, the results indicate that the half-moons are effective adaptations to the traditional land management systems to increase agricultural production in arid ecosystems, which is evident through improved vegetation conditions in southern Niger. The analysis shows that the improvement brought by the interventions continue to provide the benefits. Continued application of these adaptation techniques on a larger scale will increase agricultural production and build resilience to drought for subsistence farmers in West Africa. Quantifiable increase in efficacy of local-scale land and water management techniques, and the resulting jump in large-scale investments to scale similar efforts will help farmers enhance their resiliency in a sustainable manner will lead to a reduction in food security shortages.

PERAN FOOD AND AGRICULTURE ORGANIZATION (FAO) DALAM MENINGKATKAN KETAHANAN PANGAN SEBAGAI UPAYA UNTUK MENANGANI KRISIS KELAPARAN DI SAHEL TAHUN 2013-2015

This research aims to describe the role of FAO as an international organization in increasing food security as an effort to deal with the hunger crisis in the Sahel in 2013-2015. This research based on 2013-2015, the Sahel region was hit by a food insecurity crisis. Poor food conditions occur due to a variety of complex factors such as a prolonged drought which has an impact on drought, soil degradation and erosion, outbreaks, and internal conflicts. As a result, people have limited access to nutritious food and experience acute malnutrition. Thus, efforts to overcome the hunger crisis in the Sahel region really need to be done. This aims to reduce the increasing number of hunger and death. If there is no support, the community will have to live without adequate food and nutrition stocks. Therefore, international organizations exist to deal with the current hunger crisis, one of which is the Food and Agriculture Organization (FAO). Using the theory of liberalism and the concept of international organizations which are derivatives of liberalism, this research analyses the Sahel region. The result shows that FAO has a role to play in increasing food security in the Sahel region in overcoming the food crisis that occurred in 2013-2015.

Morphological variations among populations of Bulinus forskalii (Ehrenberg, 1831) from Cameroon

ABSTRACT Climatic stratification from equatorial rainforest to Sahelian savannah in Cameroon implies successive bioclimatic ecosystems, various natural and artificial situations that may generate morphological and genetic adaptation of populations of Bulinus forskalii (Ehrenberg, 1831) which is widely distributed throughout the country. The present research was undertaken on 955 snails sampled from 12 populations along a south–north transect to investigate morphological variations of shells. Shell colour varied from dark brown to whitish with Sudano–Sahelian shells being brownish through to whitish, shouldered and strongly carinate. Morphometric characters varied greatly from one population to another, with all shell parameters being highly correlated to shell height. Sudano–Sahelian shells were smaller than equatorial shells. From Sangmélima in the equatorial forest region to Marao in the Sudano–Sahelian region a gradual decrease of shell dimensions was apparent, indicating a morphocline. This could reflect the role played by ecological factors on snail population dynamics.

Predicting the body weight of indigenous goat breeds from morphological measurements using the classification and regression tree (CART) data mining algorithm

Classification and regression tree (CART) is a tree-based data mining algorithm that develops a model to predict an outcome. This study purposed to create a model to predict the body weight (BWT) of Red Sokoto (RS), Sahel (SH), and West African Dwarf (WAD) goats using morphological measurements (such as body length, BL; head girth, HG; head width, HDW; face length, FAL; height at wither, HTW; rump length, RL; shoulder width, SW; rump width, RW; and rump height, RH). In total, 600 goats were used for this study (200 each of RS, SH, and WAD goats). Pearson?s Moment Correlation was used to evaluate the degree of association between BWT and each morphological measurement. Concomitantly, CART analysis was performed to estimate which independent variable (morphological measurements) played a considerable role in the BWT (dependent variable) prediction. In RS and WAD goats, a positive and statistically significant (p < 0.0001) correlation was observed between BWT and each morphological measurement. However, in SH goats, both positive and negative statistically significant correlations were observed between BWT and morphological measurements. The CART analysis indicated that in RS and WAD goats, HG played a considerable role in BWT prediction, while, in SH goats, BL was considered the most critical independent variable in BWT prediction. Therefore, this study suggests that HG can be used as a prognostic index for BWT estimation in Red Sokoto and West African Dwarf, while BL can be used for Sahel goats. The SAS codes used are available via a GitHub repository (https://github.com/Soullevram/CART).

Agro-Climatic Risks Analysis in Climate Variability Context in Ségou Region

In the Sahel region, the population depends largely on rain-fed agriculture. In West Africa in particular, climate models turn out to be unable to capture some basic features of present-day climate variability. This study proposes a contribution to the analysis of the evolution of agro-climatic risks in the context of climate variability. Some statistical tests are used on the main variables of the rainy season to determine the trends and the variabilities described by the data series. Thus, the paper provides a statistical modeling of the different agro-climatic risks while the seasonal variability of agro-climatic parameters was analyzed as well as their inter annual variability. The study identifies the probability distributions of agroclimatic risks and the characterization of the rainy season was clarified.

Forced Withdrawal: The Case of France in the Sahel Region

Once part of the French colonial empire, the Sahel region played an important role in France’s Africa policy. All French presidents had their specific approach towards the region. Emanuel Macron, with his 2017 speech on the Sorbonne even claimed that the Sahel is not just important for France but the European Union as a whole. But the Europeanisation went hand in hand with serious French commitment too. Since Bamako’s invitation France had a significant military presence in the region, which may have transformed over time, but remained in the region. However until 2022 the status quo remained similar, lines of fragmentation became more and more visible. The coup epidemic, and growing Russian influence in the Central Sahel affected French interventions too, leading to a large scale withdrawal from the region. The present paper attempts to capture these changes in the relations between France and the Central Sahel.

ФАКТОРЫ СОЦИАЛЬНО-ПОЛИТИЧЕСКОЙ СТАБИЛЬНОСТИ В ГАНЕ

The article deals with studying the processes of socio-political destabilization in the countries of West Africa, as well as factors contributing to the preservation and maintenance of stability in specific countries. The countries of West Africa and, in particular the Sahel region, in recent years can be considered as the epicenter for the spread of extremism and terrorism. For that instance the study was mainly focused on Ghana as a country showing the lowest rates of terrorist attacks and episodes of socio-political instability in recent years. At the same time, in other countries of West Africa, including those neighboring Ghana, quite high rates of instability are recorded. The authors conclude that in the case of Ghana, the key stabilizing factors are religious and ethnic tolerance and a general culture of peace among Ghanaians, efforts by the country’s leadership to develop interfaith tolerance and cooperation, a developed civil society, and an effectively working extensive media network. Moreover, Ghana’s resilience to the threats of violent extremism and terrorism can be attributed to a reasonably effective democratic administrative system and the country’s good governance record, a developed security sector with decades of international peacekeeping experience, and a strong traditional system of keeping the peace and stability.

A promising relationship between the Visegrad cooperation and the Mashrek region

The relationship between the European Union (focus on the V4 countries – Czech Republic, Poland, Slovakia and Hungary) and Israel will be examined in regard to the most relevant economic and defense policy and military indicators. The paper is focusing on elaborating the political and economic relationship between the EU-V4 countries and Israel. According to empirical studies, it is necessary for the EU and Israel to work on several fields of expertise together, as the potential crisis like migration, terrorism, drug trafficking, etc. can be solved or at least pushed back only in a framework of close cooperation. The aim of this article is to present the potential for cooperation between the V4 countries and Israel, as the next waves of international migration will be coming from the Sahel region. My hypothesis is that there is a strong economic bond between V4 and the Mashrek region and besides this connection, there is a regional (Visegrad Group) growing of military and defense expenditure. The research methodology is to examine the import and export value growth between V4 countries and the Mashrek region, as well the defense and military expenditures through the databases of the World Bank and OECD.

Interrogating the Commoditization of Force in the Sahel Region: A Case Study of Mali

Intra-state conflicts are on the rise in many parts of Africa where armed non-state actors strive to take over political power from legitimate authority. In an attempt to overcome such armed confrontations and restore peace, weak nations would seek external assistance and sometimes make secret deals with private military companies that specialize in intelligence gathering, training of fighters, and supply of state-of-the-art weaponry. Using Mali as a case study, this desk study relies on secondary data available online and in print. It attempts to address the question as to how the French-led multinational forces in the Sahel region of Africa has become an endless conflict since 2013. In the light of the Game Theory, the study has found that the commoditization of force that transforms well-equipped fighters into profit-making contractors is instrumental to the trending nature of war against Islamism. The military takeover in Mali translates the determination of the commander-in-chief to occupy the driver’ seat but no one knows when the fighting will end, given that both multinational forces and insurgents are rational players in the game. The paper recommends a strict adherence to the Geneva antimercenary legislation to curtail the influence of private military companies in conflict zones.

STRATEGY FOR DEFEATING TERRORISM IN NIGERIA AND THE SAHEL

The purpose of this paper is to provide a counter-ideology framework as an alternative strategy to defeat terrorists, as military force has never been proven enough to defeat any terrorist group. The analysis relies on secondary information for systematic examination and descriptive analysis resulting in the use of Counter Terrorism Strategy (CTS) model to evaluate key assumption that acts of terrorist recruits are connected to deep politics and ideology. The paper therefore posits that the use of genuine religious messages to isolate terrorists from communities and ultimately make them short of new recruits should be considered. This finding has critical implications for institutions, governments, intelligence communities, regulators and policymakers, that the military crackdown would not yield the needed result, hence the need for a counter-ideology as a strategy to fight terrorism, particularly in the Sahel region.

Impact of High Concentrations of Saharan Dust Aerosols on Infrared-Based Land Surface Temperature Products

An analysis of three operational satellite-based thermal-infrared land surface temperature (LST) products is presented for conditions of heavy dust aerosol loading. The LST products are compared against ERA5's skin temperature (SKT) across the Sahara Desert and Sahel region, where high concentrations of dust aerosols are prevalent. Large anomalous differences are found between satellite LST and ERA5's SKT during the periods of highest dust activity, and satellite–ERA5 differences are shown to be strongly related to dust aerosol optical depth at 550 nm (DuAOD), indicating an underestimation of LST in conditions of heavy dust aerosol loading. In situ measurements from two ground stations in the Sahel region provide additional evidence of this underestimation, showing increased biases of satellite LST with DuAOD, and no significant dependence of ERA5's SKT biases on dust aerosol concentrations. The impact of atmospheric water vapor content on LST and SKT is also examined, but dust aerosols are shown to be the primary driver of the inaccurate LSTs observed. Based on comparisons with in situ data, we estimate an aerosol-induced underestimation of LST of approximately 0.9 K for every 0.1 increase in DuAOD. Analysis of brightness temperatures (BTs) in the thermal infrared atmospheric window reveals that dust aerosols have the opposite effect on BT differences compared to water vapor, leading to an underestimation of atmospheric correction by the LST retrieval algorithms. This study highlights a shortcoming of current operational LST retrieval algorithms that must be addressed.