Search Results (27)

Drought is a pervasive and intensifying climate hazard with profound implications for food security, water availability, and socioeconomic stability, particularly in sub-Saharan Africa. In Kenya, where over 80% of the landmass comprises arid and semi-arid lands (ASALs), recurrent droughts have become a critical threat to agricultural productivity and climate resilience. This study presents a comprehensive spatiotemporal analysis of seasonal drought dynamics in Kenya for June–July–August–September (JJAS) from 2000 to 2024, leveraging remote sensing-based drought indices and geospatial analysis for climate risk planning. Using the Standardized Precipitation Evapotranspiration Index (SPEI), Vegetation Condition Index (VCI), Soil Moisture Anomaly (SMA), and Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) anomaly, a Combined Drought Indicator (CDI) was developed to assess drought severity, persistence, and impact across Kenya’s four climatological seasons. Data were processed using Google Earth Engine and visualized through GIS platforms to produce high-resolution drought maps disaggregated by county and land-use class. The results revealed a marked intensification of drought conditions, with Alert and Warning classifications expanding significantly in ASALs, particularly in Garissa, Kitui, Marsabit, and Tana River. The drought persistence analysis revealed chronic exposure in drought conditions in northeastern and southeastern counties, while cropland exposure increased by over 100% while rangeland vulnerability rose nearly 56-fold. Population exposure to drought also rose sharply, underscoring the socioeconomic risks associated with climate-induced water stress. The study provides an operational framework for integrating remote sensing into early warning systems and policy planning, aligning with global climate adaptation goals and national resilience strategies. The findings advocate for proactive, data-driven drought management and localized adaptation interventions in Kenya’s most vulnerable regions. Full article

This study aimed to investigate the antimicrobial resistance, virulence gene profile, and pathogenicity of Enterococcus faecium isolated from a large-scale cattle farm in Xinjiang, China, to provide a scientific basis for the prevention and control of E. faecium infections in the region. Nineteen rectal swabs were aseptically collected from diarrheic calves for bacterial isolation. Isolates were identified through morphological observation, biochemical characterization, and PCR amplification. Homology analysis was conducted using 16S rRNA gene sequencing. Antimicrobial susceptibility was evaluated by the disk diffusion method, and key virulence genes were detected using PCR. Pathogenicity was assessed through intraperitoneal inoculation of mice, followed by histopathological examination. Three isolates were identified as E. faecium, consistent with morphological and molecular results. Biochemical tests indicated that the strains could metabolize sucrose, maltose, lactose, melibiose, and raffinose, but not sorbitol. Phylogenetic analysis revealed that isolates SCQ3 and SCQ4 shared 99.3% homology with E. faecium strain MF678878.1, while SCQ11 showed 91% similarity to strain JP2. Antimicrobial susceptibility testing indicated that SCQ11 was resistant to vancomycin. PCR analysis identified the presence of multiple virulence genes, including psaA, hyp, asal, sprE, nuc, cbh, srtA, hyl, scm, and agg. In vivo pathogenicity testing demonstrated that the vancomycin-resistant strain exhibited strong virulence in mice, with gross lesions observed in the liver, spleen, and intestines. Histopathological examination confirmed varying degrees of tissue damage, particularly in the liver and spleen. All three E. faecium isolates exhibited multidrug resistance, with one strain showing vancomycin resistance and harboring a high number of virulent genes. This strain demonstrated significant pathogenicity in vivo. These findings highlight the potential public health threat posed by multidrug-resistant E. faecium in livestock and provide essential data for regional prevention and control strategies. Full article

Pastoral livelihoods in Sub-Saharan Africa are under an increasing threat from climate change with arid and semi-arid lands (ASALs) being especially vulnerable. Climate-smart agriculture (CSA) is widely promoted as a strategy for enhancing resilience among smallholder livestock farmers by improving productivity, increasing farmers’ incomes and strengthening adaptive capacity. However, CSA adoption rates among pastoralists remains low. While existing studies emphasise socio-economic and institutional factors, this study explores the often-overlooked behavioural dimensions, attitudes, beliefs, and perceptions, which critically influence adaptation decisions. Guided by the theory of planned behaviour (TPB), this study investigates the behavioural drivers of CSA adoption among 737 livestock farmers in Kenya’s ASALs. Using ordered probit regression and structural equation modelling–confirmatory factor analysis (SEM-CFA), the results reveal that attitudes and perceived behavioural control are significant predictors of farmer intention to adopt CSA practices, with perceived behavioural control being the most influential predictor. Farmers with a positive attitude and confidence in their ability to implement CSA practices are more likely to adopt them. The study findings suggest that efforts to promote CSA adoption should prioritise transforming attitudes and building practical confidence by increasing exposure to demonstration farms and implementing awareness-raising initiatives within pastoral communities. Full article

This paper examines how demographic characteristics, institutional structures, and livelihood strategies shape household resilience to climate variability and drought in West Pokot County, one of Kenya’s most climate-vulnerable arid and semi-arid lands (ASALs). Using a mixed-methods approach, it combines household survey data with three statistical techniques: Multinomial Logistic Regression (MLR) assesses the influence of gender, age, and education on livestock ownership and livelihood choices; Multiple Correspondence Analysis (MCA) reveals patterns in institutional access and adaptive practices; and Stepwise Linear Regression (SLR) quantifies the relationship between resilience strategies and agricultural productivity. Findings show that demographic factors, particularly gender and education, along with access to veterinary services, drought-tolerant inputs, and community-based organizations, significantly shape resilience. However, trade-offs exist: strategies improving livestock productivity may reduce crop yields due to resource and labor competition. This study recommends targeted interventions, including gender-responsive extension services, integration of indigenous and scientific knowledge, improved infrastructure, and participatory governance. These measures are vital for strengthening resilience not only in West Pokot but also in other drought-prone ASAL regions across sub-Saharan Africa. Full article

Background/Objectives: Antibiotic resistance gene (ARG) spread is driven by horizontal gene transfer (HGT). Ciliated protozoa may contribute to this process, as their predation has been shown to facilitate HGT in certain bacteria. Here, this phenomenon was further investigated using A. salmonicida subsp. salmonicida. This fish pathogen bears an extensive and dynamic plasmidome, suggesting a high potential for HGT. Methods: A. salmonicida strains carrying one of three conjugative plasmids bearing ARGs (pSN254b, pRAS1b or pAsa4b) were cocultured with a recipient, either A. salmonicida, E. coli or A. hydrophila. Conjugation rates were assessed in the presence and absence of the ciliate Tetrahymena borealis. PCR genotyping confirmed the acquisition of the conjugative plasmids and was used to verify the mobilization of other plasmids. Results: The basal rate of conjugation observed was high. Under the conditions studied, ciliate predation did not appear to influence the conjugation rate, except at higher proportions of ciliates, which typically hampered conjugation. Microscopy revealed that most bacteria were digested in these conditions. PCR screening demonstrated that small mobilizable plasmids from A. salmonicida (pAsa1, pAsa2, pAsa3, and pAsal1) were acquired by the recipients along with the conjugative plasmids, with a slight effect of the ciliates in some donor/recipient cell combination. Conclusions: These results highlight how A. salmonicida can conjugate efficiently with different species and how complex its relationship with ciliates is. Full article

This study aimed to assess child protection-related needs among drought-affected populations in selected arid counties in Kenya. The specific objectives included: to understand the different underlying vulnerabilities that children and adolescents face during drought with a gender and disability lens; to assess the current or potential presence of emergency risks and their likelihood of occurrence, the capacities, and coping mechanisms of families; identify emerging areas of concern regarding children and adolescents, including those with disability; and informing the interventions through development partners and relevant government ministries. This study adopted a non-experimental design that utilized a mixed-methods approach. The quantitative data collection involved a survey of 1800 households. The information was collected about children (i.e., individuals aged 0–17), their caregivers, and their households. Two methods were used to collect qualitative data. These included Key Informant Interviews (KIIs) and Focus Group Discussions (FGDs). The study established that during drought and in the recovery period, there were increased cases of children dropping out of school mainly due to the migration of families. Child labour and household chores were also mentioned as other vulnerabilities that children and adolescents faced during drought. The findings also noted an inter-linkage between female genital mutilation (FGM), child marriage, and teenage pregnancy across all communities under study. The difficulties occasioned by drought forced many families in ASAL counties to prepare their girls for marriage through the practice of FGM. Despite the high occurrences of sexual violence against children, child marriage, teenage pregnancy, and neglect, the child protection services available for affected children were low. This study recommends strengthening child protection structures at the community level by building the recruitment and capacity of child protection volunteers; sensitizing both parents and children to knowing the proper reporting channels in case of child protection issues; and strengthening the engagement of grassroots organisations, community-based groups, and local-level networks to prevent and respond to child protection concerns. Full article

The Asal–Ghoubbet Rift area comprises basaltic rocks with similar compositions that were formed by volcanic eruptions. To gain insight into the magmatic processes of these volcanic formations, we investigated the mineral chemistry of plagioclase macrocrysts and microcrysts found in the basaltic rocks by using an electron probe micro-analyzer (EPMA). These basaltic rocks contain olivine, pyroxene, euhedral plagioclase macrocrysts, and euhedral to subhedral plagioclase microcrysts. These plagioclase macrocrysts reach up to 4 cm in length in the form of giant crystals as plagioclase ultraphyric basalts (PUBs). They have a mineral composition varying from bytownite to labradorite with anorthite content ranging from An₅₃ to An₈₆. Also, the microcrysts of all these volcanic rocks are characterized by labradorite and andesine compositions with An_22–80. According to the calculated plagioclase thermobarometry, the crystallization temperature of the plagioclase macrocrysts and microcrysts is 1082 to 1216 °C and 1072 to 1203 °C, respectively, and the pressure is 3.92 to 14.51 kbar for the macrocrysts and 2.99 to 14.84 kbar for the microcrysts. Based on these thermobarometry results for the plagioclases, we conclude that the volcanic formations located in the Asal–Ghoubbet area would have come from different eruptions from a single magmatic chamber. Full article

The objective of this research is to assess the influence of effective supply chain management on the success of transport infrastructure projects, considering the moderating effects of building information modeling (BIM) and environmental factors. Data were collected through questionnaires from construction projects and subjected to analysis to gain insights into the contributions of various supply chain management strategies to the overall performance of transport infrastructure projects, as well as how the presence of BIM and environmental considerations affect this relationship. The data were subjected to analysis using partial least squares structural equation modeling (PLS-SEM). The results of this investigation revealed a significant impact of supply chain management practices in the construction industry on the performance of transport infrastructure projects, with BIM and environmental considerations acting as moderators in this association. This study holds both practical and theoretical significance, as it contributes to the existing body of knowledge by shedding light on the role of supply chain management in construction and its influence on the success of transport infrastructure projects while also exploring the moderating influence of BIM and environmental factors. The findings provide valuable perspectives for improving supply chain management practices in construction, thereby enhancing the outcomes of transport infrastructure projects. Full article

The UASNs are widely used in underwater communications and monitoring, and many applications require accurate information regarding the position of nodes. However, intentional attacks against devices or information transmission may exist in the network, and the localization process is periodic, so it is necessary to quickly address attacks and optimize the network structure. This paper proposed an anchor node self-adaptive adjustment localization scheme (ASAL), in which the anchor node can adjust the state and depth of its participation. Two filters were used to adjust the states of referable nodes. The first filter was based on the distance difference of reverse information transmission after direct localization based on anchor nodes. The second was based on the error of the anchor node’s reverse localization after network localization was completed. In addition, a depth-adjustment mechanism of anchor nodes was proposed to optimize the network structure, the virtual force vector was introduced to describe the cost of depth adjustment, and the whale optimization algorithm was used to converge to the depth with the minimum total cost. The simulation results showed that the scheme can ensure localization accuracy and coverage in attack scenarios and reduce localization energy consumption. Full article

At the center of the Republic of Djibouti, an eroded rift called Asal is located where tectonic and magmatic activities can be observed at the surface. Multiple studies were carried out with different exploration methods, such as structural, geophysical and hydrogeological, to understand rifting processes and characterize the subsurface of this rift. Among these subsurface exploration methods, the deep geoelectrical structures need to be better defined with the magnetotelluric (MT) method to better delineate the deep resistivity structures. With the objective of improving our understanding of the deep rift structure, magnetotelluric (MT) data acquired in the Asal rift were analyzed and inverted to build a 2D electrical conductivity model of the hydrothermal system. To achieve this, a dimensionality analysis of the MT data along a 2D profile perpendicular to the rift axis was carried out. Results of this analysis justify the approximation of 2D conductivity structure. Then, 2D inversion models were achieved to build models of the conductive structures. Dimensionality analysis results revealed the existence of electrical anisotropy. Consistent correlation between geoelectric strike and electrical anisotropy direction was suggested. Electrical anisotropy direction determined from the ellipticity of the phase tensor for the short periods was interpreted as the consequence of tectonic activity and horizontal deformation of the rift. Moreover, electrical anisotropy direction for the long periods was assumed to be related to the effects of combined magmatic-tectonic activities with predominant magma/dyke intrusion, which implies the vertical deformation and the subsidence of the rift and may imply the alignment of Olivine. Moreover, the variation and rotation of paleo and recent stress fields direction of plate motion in Asal rift located at the junction of three diverging plates—Arabia, Nubia and Somalia—over geological time can generate both magmatic and tectonic activities which in turn can induce a preferred direction of electrical anisotropy which is the direction of the highest conductivity. While the north-south electrical anisotropy direction is parallel to the direction of Red Sea Rift propagation, the north-east electrical anisotropy direction is aligned with the extension direction between Arabia and Somalia plates. Results of the 2D inversion models presented for the Asal rift allowed to identify two superimposed conductive units close to the surface and are interpreted as a shallow aquifer and a wide potential hydrothermal system. These conductive mediums are overlying a relatively resistive medium. The latter is associated with a magmatic system likely containing hot and/or partly molten rocks. The 2D conductivity model developed in this study could be considered as conceptual model of Asal rift prior to modeling multiphase fluid flow and heat transfer and/or could be used to identify the hydrothermal system for future drilling target depth of geothermal exploration. Full article

Asal rift is an aerial rift segment resulting from the westward propagation of the Aden ridge into the Afar Depression. Geothermal manifestations such as hot springs and fumaroles, fault creep, conductivity anomaly, and high geothermal gradient were observed both at the surface and in the subsurface. Despite many scientific works conducted in Asal to understand the rifting mechanisms, the hydrothermal fluid circulation still needs to be evaluated since it is based on simplified conceptual models. To further contribute and progress toward a quantitative evaluation of fluid circulation, a 2D numerical model perpendicular to the rift axis was developed with the objective of better understanding the role of subsurface anisotropy in fluid flow and heat transfer in the Asal rift. Numerical modeling of multiphase flow and heat transfer was carried out with an equivalent porous medium intersected by fault zones having greater permeability. Horizontal anisotropic permeability and magmatic fluid release were taken into account with different simulation scenarios. The results indicate that fault zones act as recharge/discharge areas depending on their location, permeability, and number. Simulations considering horizontal anisotropic permeability allowed the reproduction of the thermal state observed in geothermal wells with the expected general pattern of fluid circulation in the Asal rift. Comparing our result with a recent study made with a 2D numerical modeling parallel to the rift axis, we suggest the presence of a saddle point where fluid flow is both to the northeast and to the southwest direction of the rift. Moreover, magmatic fluid release assumed in two simulation scenarios showed to have an impact on the hydrological behavior of fault zones and facilitate the development of super-critical flow at the center of the rift. Full article

Many pastoralist communities around the world rely on the traditional livestock farming sub-sector for a living and to meet their food consumption needs. Food insecurity, on the other hand, is a growing concern in these communities, and the reasons for this must be understood in order to implement appropriate policy measures to improve food security. Based on data collected from Aramis-Adaar and the Asale pastoralist and agro-pastoralist (hereafter (agro)pastoralist) communities in Afar, Ethiopia, this study investigates the relationship between social–cultural–economic characteristics and food (in)security. To measure the severity of food insecurity and assess the associations, we used the household food insecurity access score (HFIAS) and ordered logistic regression, respectively. Our findings show that food insecurity in the study area is persistent where improvement in food security is significantly constrained by some culture elements (the (agro)pastoralists’ cultural orientation). It has also been found that the (agro)pastoralists’ market exchange practices, as well as the centuries-old practice of guro (livestock mobility as a traditional coping strategy), help to reduce food insecurity. These findings contribute to our understanding of food insecurity in the (agro)pastoralist context and thereby add to the ‘move-up’ or ‘move-out’ pastoralist development policy debate. Therefore, the results suggest that there is a need for a combination of approaches that combine pastoral production services and market production orientation and capitalize on (agro)pastoralist traditions, such as mobility, to promote sustained (agro)pastoral livelihoods and ‘move-up’ the pastoral production system. Full article

Dihydrogen (H₂) is generated by fluid–rock interactions along mid-ocean ridges (MORs) and was not, until recently, considered as a resource. However, in the context of worldwide efforts to decarbonize the energy mix, clean hydrogen is now highly sought after, and the production of natural H₂ is considered to be a powerful alternative to electrolysis. The Afar Rift System has many geological features in common with MORs and offers potential in terms of natural H₂ resources. Here, we present data acquired during initial exploration in this region. H₂ contents in soil and within fumaroles were measured along a 200 km section across the Asal–Ghoubbet rift and the various intervening grabens, extending from Obock to Lake Abhe. These newly acquired data have been synthesized with existing data, including those from the geothermal prospect area of the Asal–Ghoubbet rift zone. Our results demonstrate that basalt alteration with oxidation of iron-rich facies and simultaneous reduction in water is the likely the source of the hydrogen, although H₂S reduction cannot be ruled out. However, H₂ volumes at the surface within fumaroles were found to be low, reaching only a few percent. These values are considerably lower than those found in MORs. This discrepancy may be attributed to bias introduced by surface sampling; for example, microorganisms may be preferentially consuming H₂ near the surface in this environment. However, the low H₂ generation rates found in the study area could also be due to a lack of reactants, such as fayalite (i.e., owing to the presence of low-olivine basalts with predominantly magnesian olivines), or to the limited volume and slow circulation of water. In future, access to additional subsurface data acquired through the ongoing geothermal drilling campaign will bring new insight to help answer these questions. Full article

The Republic of Djibouti has untapped potential in terms of renewable energy resources, such as geothermal, wind, and solar energy. This study examines the economic feasibility of green hydrogen production by water electrolysis using wind and geothermal energy resources in the Asal–Ghoubbet Rift (AG Rift), Republic of Djibouti. It is the first study in Africa that compares the cost per kg of green hydrogen produced by wind and geothermal energy from a single site. The unit cost of electricity produced by the wind turbine (0.042 $/kWh) is more competitive than that of a dry steam geothermal plant (0.086 $/kWh). The cost of producing hydrogen with a suitable electrolyzer powered by wind energy ranges from $0.672/kg H₂ to $1.063/kg H₂, while that produced by the high-temperature electrolyzer (HTE) powered by geothermal energy ranges from $3.31/kg H₂ to $4.78/kg H₂. Thus, the AG Rift area can produce electricity and green hydrogen at low-cost using wind energy compared to geothermal energy. The amount of carbon dioxide (CO₂) emissions reduced by using a “Yinhe GX113-2.5MW” wind turbine and a single flash geothermal power plant instead of fuel-oil generators is 2061.6 tons CO₂/MW/year and 2184.8 tons CO₂/MW/year, respectively. Full article

According to the Intergovernmental Panel on Climate Change, the Horn of Africa is getting drier. This research aims at assessing browning and/or greening dynamics and the suitability of Sentinel-2 satellite images to map changes in land cover in a semiarid area. Vegetation dynamics are assessed through a remote sensing approach based on densely vegetated areas in a pilot area of North Horr Sub-County, in northern Kenya, between 2016–2020. Four spectral vegetation indices are calculated from Sentinel-2 images to create annual multi-temporal images. Two different supervised classification methods—Minimum Distance and Spectral Angle Mapper—are then applied in order to identify dense vegetated areas. A general greening is found to have occurred in this period with the exception of the year 2020, with an average annual percentage increase of 19%. Results also highlight a latency between climatic conditions and vegetation growth. This approach is for the first time applied in North Horr Sub-County and supports local decision-making processes for sustainable land management strategies. Full article