Browsing by Subject "Africa"

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Assessing human mobility and its climatic and socioeconomic factors for sustainable development in Sub-Saharan Africa
(2023) Li, Qirui; Samimi, Cyrus
Promoting human mobility and reducing inequality among countries are the Sustainable Development Goals’ (SDGs) targets. However, measuring human mobility, assessing its heterogeneity and changes, and exploring associated mechanisms and context effects are still key challenges, especially for developing countries. This study attempts to review the concept of human mobility with complex thinking, assess human mobility across forty countries in Sub-Saharan Africa (SSA), and examine the effect of climatic and socioeconomic factors. Based on the coined definition of human mobility, international migration and cross-border trips are taken to assess human mobility in terms of permanent migration and temporary moves. The forty SSA countries are hence classified into four mobility groups. Regression models are performed to identify key determinants and estimate their effects on mobility. The results reveal that seven of these forty countries had a high mobility, whereas most experienced a decline in permanent migration. Lesotho, Cabo Verde, and Namibia presented high temporary moves, while Eritrea, Rwanda, Equatorial Guinea, and Liberia had a high permanent migration. Climatic and socioeconomic conditions demonstrated significant effects on mobility but were different for temporary moves and permanent migration. Wet extremes reduced mobility, whereas extreme temperature variations had positive effects. Dry extremes promoted permanent migration but inhibited temporary moves. Economic wealth and political instability promoted permanent migration, while the young population counteracted temporary moves. Food insecurity and migrant networks stimulated human mobility. The analysis emphasises the interest in analysing human mobility for risk reduction and sustainability management at the multi-county level.
Livestock phenomics and genetic evaluation approaches in Africa: current state and future perspectives
(2023) Houaga, Isidore; Mrode, Raphael; Opoola, Oluyinka; Chagunda, Mizeck G. G.; Mwai, Okeyo A.; Rege, John E. O.; Olori, Victor E.; Nash, Oyekanmi; Banga, Cuthbert B.; Okeno, Tobias O.; Djikeng, Appolinaire
The African livestock sector plays a key role in improving the livelihoods of people through the supply of food, improved nutrition and consequently health. However, its impact on the economy of the people and contribution to national GDP is highly variable and generally below its potential. This study was conducted to assess the current state of livestock phenomics and genetic evaluation methods being used across the continent, the main challenges, and to demonstrate the effects of various genetic models on the accuracy and rate of genetic gain that could be achieved. An online survey of livestock experts, academics, scientists, national focal points for animal genetic resources, policymakers, extension agents and animal breeding industry was conducted in 38 African countries. The results revealed 1) limited national livestock identification and data recording systems, 2) limited data on livestock production and health traits and genomic information, 3) mass selection was the common method used for genetic improvement with very limited application of genetic and genomic-based selection and evaluation, 4) limited human capacity, infrastructure, and funding for livestock genetic improvement programmes, as well as enabling animal breeding policies. A joint genetic evaluation of Holstein-Friesian using pooled data from Kenya and South Africa was piloted. The pilot analysis yielded higher accuracy of prediction of breeding values, pointing to possibility of higher genetic gains that could be achieved and demonstrating the potential power of multi-country evaluations: Kenya benefited on the 305-days milk yield and the age at first calving and South Africa on the age at first calving and the first calving interval. The findings from this study will help in developing harmonized protocols for animal identification, livestock data recording, and genetic evaluations (both national and across-countries) as well as in designing subsequent capacity building and training programmes for animal breeders and livestock farmers in Africa. National governments need to put in place enabling policies, the necessary infrastructure and funding for national and across country collaborations for a joint genetic evaluation which will revolutionize the livestock genetic improvement in Africa.
Nature's contributions to human well‐being under climate change: Evidence from Central and Eastern Madagascar
(2024) Petzold, Jan; Kosanic, Aleksandra; Rakoto Joseph, Felana; Rajaonarivelo Andrianina, Princy; Ranaivosoa‐Toandro, Sitraka Mireille; Andriamihaja, Onintsoa Ravaka; Voahanginirina, Leonnie Marcelline; Thien, Lara; Razanajatovo, Mialy
Anthropogenic climate change has an unprecedented impact on ecosystems and their services, with severe consequences for human well‐being, particularly for the marginalised and vulnerable members of society in the Global South. The well‐being of communities relies not only on material and regulating services ecosystems provide but also on non‐material services. In this paper, we unravel the diverse ways that climate change impacts affect Nature's Contributions to People (NCP) and the well‐being of rural populations in four sites in Madagascar—a biodiversity hotspot but one of the economically poorest countries in the world. We conducted participatory community workshops, mapping and semi‐structured interviews with local residents across social subgroups to understand the mechanisms of climate‐related degradation and the resulting impacts on different dimensions of human well‐being through an NCP lens. We found that non‐material services are generally more often associated with well‐being effects. Climate change degrades material and non‐material services through sea level rise, biodiversity loss, drought, precipitation and temperature variability, with consequences for materials, companionship and labour, food and feed, and physical and psychological experiences. Loss of land and forests is expressed through ecological grief. The outcome of our research provides evidence‐based information to local policymakers, conservation practitioners, and climate change agencies. This information can help improve government efforts toward holistic conservation and climate change adaptation by addressing the impacts on the physical and mental well‐being of the most vulnerable communities. Read the free Plain Language Summary for this article on the Journal blog.
Optimizing selection efficiency in maize for the drought prone eastern and southern African environments
(2013) Kebede, Aida; Melchinger, Albrecht E.
Breeding for stress tolerance is the most cost effective way of avoiding drought-induced yield reduction in the tropics. Optimizing breeding for drought tolerance at CIMMYT could enhance the effectiveness of this multi-national breeding program and warrant fast delivery of drought tolerant materials to the farmers. Thus, the overall aim of my study was to improve the efficiency of drought tolerance breeding of maize at CIMMYT for the rapid and cost effective advancement of drought tolerant materials for the drought prone regions of the ESA (Eastern and Southern African countries). We screened a diverse source of tropical germplasm for their haploid induction rate (HIR) and the seasonal variation of this trait. We then compared various managed drought and well watered experiments conducted as line per se performance trials (LP) and testcross performance trials (TP) in Kenya and Mexico. Further, we estimated the relative selection efficiency of the principal breeding regions of CIMMYT for the tropics in ESA and Mexico with unselected and selected breeding materials. The specific objectives of my study were to (1) monitor the variation for HIR among diverse source germplasm in tropical maize, (2) determine the relative importance of general (GCA) and specific (SCA) combining abilities of the source germplasm for HIR, (3) investigate the influence of tropical summer and winter seasons and genotype × season interactions on this trait, (4) determine if LP is predictive of TP for yield under drought in sets of lines under development by the CIMMYT maize breeding program in Kenya and Mexico, (5) determine the genetic correlation between performance of lines per se under drought and testcrosses under optimal conditions and assessing its effect on yield potential, (6) examine the correlation between TP under well-watered and drought stress conditions for potential indirect selection efficiency of well-watered conditions in comparison with drought stress, (7) determine the relative importance of regional adaptation of maize hybrids to Mexico and ESA by subdividing the genotype × environment interactions and determining genotypic correlations between both regions, (8) calculate the indirect selection efficiency for selecting materials based on test results from one region on the selection gain in the other region, and (9) identify the most suitable stage for exchanging breeding materials between Mexico and ESA. Source germplasm and induction season affected HIR and MCR (mis-classification rate) considerably in tropical maize. Source germplam with high HIR and low MCR could be used in the initial stage of implementing the DH technology in the tropics. GCA effect was more important than SCA or genotype × season interaction effects for HIR in tropical maize. Thus, enhancing HIR in source germplasm can be achieved through cyclical breeding or recurrent selection. Winter season was considered the best season for induction because it provides suitable environmental conditions for higher HIR and lower MCR. Overall HIR was high enough to apply the in vivo DH technology in the routine breeding activities in tropical maize. There were moderate genotypic correlation and ISE (Indirect Selection Efficiency) values between LP and TP under drought that increased with an increase in stress level. Hence, LP trials were predictive of TP trials particularly under severe drought stress. Furthermore, screening of lines for LP under drought stress did not compromise yield potential. TP under well-watered conditions were not predictive of TP under drought stress emphasizing the need of managed drought trials to identify drought tolerant materials. With the current shift of inbred development to large scale DH line production, LP evaluations can reduce the cost of making large numbers of testcrosses and optimize breeding for drought tolerant hybrids in the tropics. The exchange of breeding materials between ESA and Mexico can be done with early and late generation materials. This is because there was negligible genotype by region interactions as compared to genotype by location interactions within each region and high genotypic correlations between the two regions. Further, ISE estimates for trials conducted in Mexico and in ESA were high. Adaptive diseases for each location might hamper the exchange of materials, however, with current molecular marker tools like marker assisted selection and genomic selection, the problem of selecting for disease resistance in the region where the disease is not prevalent seems promising. In conclusion, there are ample opportunities in the CIMMYT maize breeding program to optimize breeding for drought tolerance in the tropics through rapid and large scale production of DH lines and evaluation of these lines for LP in managed drought trials. Moreover, breeders from ESA and Mexico could benefit from each other?s materials and test results by regular exchange of breeding materials at both the early and late stages of testing.
Perceived effects of farm tractors in four African countries, highlighted by participatory impact diagrams
(2020) Daum, Thomas; Adegbola, Ygué Patrice; Kamau, Geoffrey; Kergna, Alpha Oumar; Daudu, Christogonus; Zossou, Roch Cedrique; Crinot, Géraud Fabrice; Houssou, Paul; Mose, Lawrence; Ndirpaya, Yarama; Wahab, A. A.; Kirui, Oliver; Oluwole, Fatunbi Abiodun
Agricultural mechanization is on the rise in Africa. A widespread replacement of manual labor and animal traction will change the face of African agriculture. Despite this potentially transformative role, only a few studies have looked at the effects of mechanization empirically, mostly focusing on yields and labor alone. This is the first paper that explores perceived agronomic, environmental, and socioeconomic effects together, thereby revealing linkages and trade-offs, some of which have been hitherto unknown. Data were collected using a novel data collection method called “participatory impact diagrams” in four countries: Benin, Kenya, Nigeria, and Mali. In 129 gendered focus group discussions, 1330 respondents from 87 villages shared their perceptions on the positive and negative effects of agricultural mechanization, and developed causal impact chains. The results suggest that mechanization is likely to have more far-reaching agronomic, environmental, and socioeconomic consequences than commonly assumed. Most perceived effects were positive, suggesting that mechanization can help to reduce poverty and enhance food security but other effects were negative such as deforestation, soil erosion, land-use conflicts, and gender inequalities. Accompanying research and policy efforts, which reflect variations in local agro-ecological and socioeconomic conditions, are needed to ensure that mechanization contributes to an African agricultural transformation that is sustainable from a social, economic, and environmental perspective.
Perspectives for donkey-drawn mechanization of field work in Southern Niger
(2004) Emhardt, Frank; Kutzbach, Heinz Dieter
Subsistence oriented rainfed farming in the South and extensive cattle pasturage on grassland savannas in the Sahel is the mode for life for 95 % of the people in Niger. The majority of the farmers would adopt animal drawn technology if it is reliable, inexpensive, simple to use, sound and sturdy technology without permanent risk of failure. Within the present thesis it is focused exclusively on donkey traction as a source of farm power for the location specific optimization of common farming practices for most oriented to the Djerma farmers? annual working calendar in South-West Niger. Efforts have concentrated on ridging, sowing, weeding and mulching.
Prediction of soil properties for agricultural and environmental applications from infrared and X-ray soil spectral properties
(2013) Towett, Erick Kibet; Cadisch, Georg
Many of today?s most pressing problems facing developing countries, such as food security, climate change, and environmental protection, require large area data on soil functional capacity. Conventional assessments (methods and measurements) of soil capacity to perform specific agricultural and environmental functions are time consuming and expensive. In addition, repeatability, reproducibility and accuracy of conventional soil analytical data are major challenges. New, rapid methods to quantify soil properties are needed, especially in developing countries where reliable data on soil properties is sparse, and to take advantage of new opportunities for digital soil mapping. Mid infrared diffuse reflectance spectroscopy (MIR) has already shown promise as a rapid analytical tool and there are new opportunities to include other high-throughput techniques, such as total X-ray fluorescence (TXRF), and X-ray diffraction (XRD) spectroscopy. In this study TXRF and XRD were tested in conjunction with IR to provide powerful diagnostic capabilities for the direct prediction of key soil properties for agricultural and environmental applications especially for Sub-Saharan Africa (SSA) soils. Optimal combinations of spectral methods for use in pedotransfer functions for low cost, rapid prediction of chemical and physical properties of African soils as well as prediction models for soil organic carbon and soil fertility properties (soil extractable nutrients, pH and exchangeable acidity) were tested in this study. These state-of-the-art methods for large-area soil health measurement and monitoring will aid in accelerating economic development in developing sub-Saharan Africa countries with regards to climate change, increasing water scarcity and impacts on local and global food security as well as sustainable agricultural production and ecosystem resilience in the tropics. This study has developed and tested a method for the use of TXRF for direct quantification of total element concentrations in soils using a TXRF (S2 PICOFOXTM) spectrometer and demonstrated that TXRF could be used as a rapid screening tool for total element concentrations in soils assuming sufficient calibration measures are followed. The results of the current study have shown that TXRF can provide efficient chemical fingerprinting which could be further tested for inferring soil chemical and physical functional properties which is of interest in the African soil context for agricultural and environmental management at large scale. Further, this thesis has helped to improve understanding of the variation and patterns of element concentration data for 1034 soil samples from 34 stratified randomly-located 100-km2 ?sentinel? sites across SSA and explored the link between variability of soil properties and climate, parent material, vegetation types and land use patterns with the help of Random Forests statistics. Our results of total element concentration were within the range reported globally for soil Cr, Mn, Zn, Ni, V, Sr, and Y and in the high range for Al, Cu, Ta, Pb, and Ga. There were significant variations (P < 0.05) in total element composition within and between the sites for all the elements analysed. In addition, the greatest proportion of total variance and number of significant variance components occurred at the site (55-88%) followed by the cluster nested within site levels (10-40%). Our results also indicated that the strong observed within site as well as between site variations in many elements can serve to diagnose their soil fertility potential. Explorations of the relationships between element composition data and other site factors using ?randomForest? statistics have demonstrated that all site and soil-forming factors have important influence on total elemental concentrations in the soil with the most important variables explaining the main patterns of variation in total element concentrations being cluster, topography, landuse, precipitation and temperature. However, the importance of cluster can be explained by spatial correlation at distances of <1 km. This study has also analysed the potential of combining analyses undertaken using MIR spectroscopy and TXRF on 700 soil samples from 44 ?sentinel? sites distributed across SSA. MIR prediction models for soil organic carbon, and other soil fertility properties (such as soil extractable nutrients, pH, exchangeable acidity and soil texture) were developed using Random Forests (RF) regression and the current study has added total element concentration data to the residuals of the MIRS predictions to test how they can improve the MIR prediction accuracies. The RF approach out-perfomed the conventional partial least squares regression (PLSR) on simultaneous determination of soil properties; and in addition, RF results were also easily interpretable, computationally much faster and did not rely on data transformations or any other assumptions about data distributions compared to PLSR. With respect to the potential of combining TXRF and MIR spectra, including total element concentration data from TXRF analysis in the RF models significantly reduced root mean square error of prediction by 63% for Ecd, 54% for Mehlich-3 S, and 53% for Mehlich-3 Na. Thus, TXRF spectra were a useful supplement to improve prediction of soil properties not well predicted by MIRS. The prediction improvement from including TXRF was due to detection of a few outliers that did not appear as MIR spectral outliers. MIR showed remarkable ability to capture total elemental composition effects on physico-chemical soil properties but TXRF may have potential for outlier detection in large studies. This study has also helped to develop high-throughput spectral analytical methods and provided recommendations on optimal spectral analytical methods for the Globally Integrated Africa Soil Information Service (AfSIS) Project. Successfully developed methods in this study will become part of the standard AfSIS procedures.
Untersuchungen leistungsspezifischer Kenngrößen der Zugtiernutzung im südlichen Niger
(1991) Betker, Joachim; Kutzbach, Heinz Dieter
Im Niger wie auch in anderen Ländern verlangt die Ernährung einer ständig wachsenden Bevölkerung nachhaltige Produktionssteigerungen im landwirtschaftlichen Bereich. Die Weiterentwicklung der traditionellen Handarbeit durch die Mechanisierung von Feld- und Transportarbeiten ermöglicht durch eine Steigerung der Arbeitsproduktivität diese notwendige Erhöhung der agrarwirtschaftlichen Produktion. Zielsetzung der vorliegenden Arbeit ist es, Ansätze zu einer Optimierung der Zugtiernutzung durch die Ermittlung leistungsspezifischer Kenngrößen aufzuzeigen. Hierfür ist die Anpassung des Leistungsbedarfs der lokal eingesetzten Gerätetypen an das Leistungsvermögen der vorhandenen Zugtiere von besonderer Bedeutung.