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Wind erosion is one of the main causes of land degradation and desertification. Clarifying the spatiotemporal variations of wind erosion and the dominant factors of its spatial characteristics and the temporal trend will contribute to the establishment of appropriate wind erosion control and management practices, which is essential for combating global land degradation and strengthening ecological protection in drylands. Here, we assessed wind erosion in Africa during 2001–2020 based on the Revised Wind Erosion Equation (RWEQ). We also analyzed the influential factor of spatial characteristics and temporal variation based on machine learning and other methods under different aridity. Results revealed that the average annual wind erosion modulus was 16,672 t/km2/a in Africa during 2001–2020, with hyper‐arid areas and arid areas accounting for more than 90% of the total wind erosion modulus. The spatial characteristics of wind erosion were dominated by natural factors but not anthropogenic activities. Except in hyper‐arid areas, wind speed and vegetation coverage together dominated the spatial characteristics. Wind speed was the dominant factor in wind erosion change, while in arid and semi‐arid areas, the capability of vegetation coverage to affect wind erosion change was comparable to wind speed. It can be concluded that, although revegetation does contribute to the reduction of wind erosion in arid and semi‐arid areas, taking into account water resource constraints and land use conflicts, large plantations can be replaced with windbreaks to increase vegetation coverage while reducing near‐surface wind speed, which improves the sustainability of ecological projects aimed at combating land degradation and desertification. Plain Language Summary: Wind erosion can decrease soil fertility and is the main cause of dust storms in drylands. Therefore, clarifying the spatial and temporal dynamics of wind erosion is very important for combating land degradation and desertification. We used the Revised Wind Erosion Equation to assess the wind erosion in Africa over the period 2001–2020 and analyzed its driving forces. This study found a fluctuating decline of wind erosion in Africa over the past 20 years, with severe wind erosion mainly in the Sahara Desert, the Somali Peninsula, and Southern Africa, and with hyper‐arid areas and arid areas accounting for more than 90% of the wind erosion modulus. Wind speed was the dominant factor in the spatial and temporal dynamics of wind erosion, especially in the hyper‐arid areas where wind erosion was most severe. However, vegetation coverage also played an equally crucial role in reducing wind erosion in arid and semi‐arid areas. Therefore, slowing down the wind speed and increasing the vegetation coverage are both important approaches to restricting wind erosion, but considering the limitation of water resources, the related ecological projects should replace large‐scale planting with windbreaks to realize sustainability in combating land degradation and desertification. Key Points: Wind erosion in hyper‐arid and arid areas accounted for more than 90% of Africa's total wind erosion modulusWind speed dominated the spatial characteristics of wind erosion in Africa and contributed to an 81.66% variation in the wind erosionSubstituting large‐scale plantations with windbreaks can enhance the sustainability of ecological engineering projects to combat land degradation and desertification [ABSTRACT FROM AUTHOR]

A virtual project team (VPT) or a geographically dispersed project team is a group of geographically and/or temporally dispersed individuals brought together via information and telecommunication technologies to work towards a common goal. The global village expands daily, and the search for additional revenue continues beyond borders. There is, therefore, a dire need for an integrated approach to managing projects effectively and proactively across regional barriers and beyond national borders. At present, knowledge of VPTs is not only limited but also fragmented. Grounded Theory study investigated the main VPT driving forces that have an impact on improving the performance of VPTs. In total, 27 participants took part in face-to-face interviews. A total of about 125 journals and books were reviewed as part of Literature research. Literature research was conducted before and after the field study in an effort to uncover the driving forces for improving the performance of VPTs. The findings indicate: Strategic Support system, Strategic Leadership, sound VPT PM, Advocating ICT critical, Government support, and Building a Virtual Community as key drivers for improving the performance of VPTs in Africa. The research provides insights by expanding the domain and gaining more knowledge of VPTs and other technologies in the project management field, thereby creating a synergistic whole in a previously unexplored Sub-Saharan context. The findings are useful to project managers and key players on important lessons and an understanding of drivers for improving the performance of their engagement that would lead to improved future project delivery through hexagon of driving forces associated with VPTs in South Africa. [ABSTRACT FROM AUTHOR]

The potential for mitigating climate change is growing worldwide, with an increasing emphasis on reducing CO 2 emissions and minimising the impact on the environment. African continent is faced with the unique challenge of climate change whilst coping with extreme poverty, explosive population growth and economic difficulties. CO 2 emission patterns in Africa are analysed in this study to understand primary CO 2 sources and underlying driving forces further. Data are examined using gravity model, logarithmic mean divisia index and Tapio's decoupling indicator of CO 2 emissions from economic development in 20 selected African countries during 1984−2014. Results reveal that CO 2 emissions increased by 2.11% (453.73 million ton) over the research period. Gravity centre for African CO 2 emissions had shifted towards the northeast direction. Population and economic growth were primary driving forces of CO 2 emissions. Industrial structure and emission efficiency effects partially offset the growth of CO 2 emissions. The economic growth effect was an offset factor in central African countries and Zimbabwe due to political instability and economic mismanagement. Industrial structure and emission efficiency were insufficient to decouple economic development from CO 2 emissions and relieve the pressure of population explosion on CO 2 emissions in Africa. Thus, future efforts in reducing CO 2 emissions should focus on scale-up energy-efficient technologies, renewable energy update, emission pricing and long-term green development towards sustainable development goals by 2030. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The virtual water (VW) approach offers a crucial heuristic tool to analyze water and food security by considering the water embedded in grain during the whole production process. African landlocked developing countries (LLDCs) continually suffer from an escalating food crisis and water resources and socioeconomic policy and water conservation strategy derived from the water-food nexus of virtual water trade (VWT) systems and resources may be the solution. Using a trade gravity model and multilateral data, this study evaluated grain VW flux patterns and 11 main drivers of VWT between 16 African LLDCs and their partners. Besides, the feedback path of VW flows corresponding to the socio-ecohydrological variability was studied using the impulse response function. The findings revealed that net virtual water import (VWI) varied across all 16 African LLDCs, ranging from 1.67 Bm3 to 10.28 Bm3 during 2000 and 2020, with an estimated yearly grain VWI of 105.61 Bm3. Green, blue, and grey water accounted for about 79.3%, 14.7%, and 5.98% of the total grain VWI, respectively. Ethiopia had the highest grain VWI among the African LLDCs. Grain VWI fluxes were significantly and positively driven by population growth and per capita GDP, which were expected to continue in the future. It was concluded that the quantitative analysis of grain VWT patterns and driving forces using the VW theory for LLDCs can be instrumental for guiding the socioeconomic policy and water conservation strategy. To effectively achieve sustainable water security and grain production, earmarked future VW strategy is required. Decision-makers should incorporate rational VW strategies and socio-ecohydrological factors into the monitoring system from a multidisciplinary perspective. [Display omitted] • Broadly assessed the bilateral virtual water (VW) fluxes drivers. • Developed a trade gravity model. • Significantly enhanced the grain VW imports by population and per capita GDP. • Proposed future research frontiers based on socio-ecohydrological approach. [ABSTRACT FROM AUTHOR]

The origin of the African savanna has been traced back to 10–6 million years (Ma) ago, but the mechanisms driving its evolution are hotly debated, and include global atmospheric CO 2 , regional fire activity, herbivore competition, and hydrological climate change. Here, we present the first microcharcoal-based fire activity records covering the last ~7 Ma at four International Ocean Discovery Program (IODP) sites near southern Africa. The records show that fire activities in both savanna and non-savanna regions were stable during this interval. Grass vegetation in burnt biomass continued to expand from 6 Ma into the present savanna region, whereas no grass expansion was observed in non-savanna regions. A compilation of regional data suggests asynchronous C4 grass expansion since 6 Ma on the African Continent. We consider that CO 2 concentrations and wildfires might have caused the first appearance of C4 plants at ~10 Ma and ~ 7–6 Ma, respectively. Since 6 Ma, the regional climate promoted expansion of C4 plants into the present-day savanna habitat. • Microcharcoals in four IODP boreholes surrounding the southern Africa are studied. • Microcharcoal influxes show the stable wildfire trends since 6 Ma ago. • Microcharcoal morphologies show the C4 vegetation expanded along specific routes. • The C4 expansion is attributed to the regional climate rather than CO 2 or wildfire. [ABSTRACT FROM AUTHOR]