Migration is an important, but threatened ecological process. Conserving migration requires the maintenance of functional connectivity across sufficiently large areas. Therefore, we need to know if, ...where and why species migrate. Elephants are highly mobile and can travel long distances but we do not know if they migrate. Here, we analysed the movement trajectories of 139 savanna elephants (Loxodonta africana) within eight clusters of protected areas across southern Africa to determine if elephants migrate, and if so, where, how and why they migrate. Only 25 of these elephants migrated. Elephants are a facultative partially migratory species, where only some individuals in a population migrate opportunistically, and not every year. Elephants migrated between distinct seasonal ranges corresponding to southern Africa's dry and wet seasons. The timing of wet season migrations was associated with the onset of rainfall and the subsequent greening up of forage. Conversely, the duration, distance, and the timing of dry season migrations varied idiosyncratically. The drivers of elephant migration are likely a complex interaction between individual traits, density, and the distribution and availability of resources. Despite most migrations crossing administrative boundaries, conservation networks provided functional space for elephants to migrate.
We analyze the potential effect of global warming levels (GWLs) of 1.5 °C and 2 °C above pre-industrial levels (1861−1890) on mean temperature and precipitation as well as intra-seasonal ...precipitation extremes over the Greater Horn of Africa. We used a large, 25-member regional climate model ensemble from the Coordinated Regional Downscaling Experiment and show that, compared to the control period of 1971−2000, annual mean near-surface temperature is projected to increase by more than 1 °C and 1.5 °C over most parts of the Greater Horn of Africa, under GWLs of 1.5 °C and 2 °C respectively. The highest temperature increases are projected in the northern region, covering most parts of Sudan and northern parts of Ethiopia, and the lowest temperature increases are projected over the coastal belt of Tanzania. However, the projected mean surface temperature difference between 2 °C and 1. 5 °C GWLs is higher than 0.5 °C over nearly all land points, reaching 0.8 °C over Sudan and northern Ethiopia. This implies that the Greater Horn of Africa will warm faster than the global mean. While projected changes in precipitation are mostly uncertain across the Greater Horn of Africa, there is a substantial decrease over the central and northern parts of Ethiopia. Additionally, the length of dry and wet spells is projected to increase and decrease respectively. The combined effect of a reduction in rainfall and the changes in the wet and dry spells will likely impact negatively on the livelihoods of people within the coastal cities, lake regions, highlands as well as arid and semi-arid lands of Kenya, Tanzania, Somalia, Ethiopia and Sudan. The probable impacts of these changes on key sectors such as agriculture, water, energy and health sectors, will likely call for formulation of actionable policies geared towards adaptation and mitigation of the impacts of 1.5 °C and 2 °C warming.
Free radicals and reactive species are widely believed to contribute to the development of several diseases by causing oxidative stress and eventually oxidative. Vernonia amygdalina (Astereacea) is a ...small shrub or tree between 1 and 5m high growing throughout tropical Africa. Plants are generally known as bitter leaves is well cultivated and is a general market for merchandise in several countries. The purpose of this study was to determine the antioxidant activity of hexane fraction from ethanol extract od Frican leaves (Vernonia amygdalina Del.). The method used in this study was the DPPH (1,1-Diphenil-2-Picrylhydrazyl) method. The result of phytochemical screening showed that ethanolic extract of African leaves contained a composition of secondary metabolites of alkaloids, flavonoids, tannins, steroids/triterpenoids and saponins. The antioxidant activity of the extract of n-hexane fraction was classified as very weak with an IC50 value of 317.98 ppm.
Abstract
Countries across Africa continue to face major challenges in education. In this review, we examine 145 recent empirical studies (from 2014 onward) on how to increase access to and improve ...the quality of education across the continent, specifically examining how these studies update previous research findings. We find that 64% of the studies evaluate government-implemented programs, 36% include detailed cost analysis and 35% evaluate multiple treatment arms. We identify several areas where new studies provide rigorous evidence on topics that do not figure prominently in earlier evidence syntheses. New evidence shows promising impacts of structured pedagogy interventions (which typically provide a variety of inputs, such as lesson plans and training for teachers together with new materials for students) and of mother tongue instruction interventions, as well as from a range of teacher programs, including both remunerative (pay-for-performance of various designs) and non-remunerative (coaching and certain types of training) programs. School feeding delivers gains in both access and learning. New studies also show long-term positive impacts of eliminating school fees for primary school and positive impacts of eliminating fees in secondary school. Education technology interventions have decidedly mixed impacts, as do school grant programs and programs providing individual learning inputs (e.g., uniforms or textbooks).
Inspired by a recent and ongoing debate about whether foreign direct investment (FDI) represents a blessing for or an impediment to economic, social, and political development in FDI host countries ...this paper addresses two issues: Does the presence of foreign investors impact the occurrence of petty corruption? If so, what are the main underlying mechanisms? Geocoding an original firm-level dataset and combining it with georeferenced household survey data, this is a first attempt to analyse whether the presence of foreign investors is associated with changes in local corruption around foreign-owned production facilities in 19 Sub-Saharan African countries. Applying an estimation strategy that explores the spatial and temporal variation in the data, we find strong and consistent evidence that the presence of foreign firms increases bribery among people living nearby. When examining two potential channels, we find no clear support that FDI-induced economic activity leads to more corruption. In contrast, the results provide evidence that FDI affects corruption via norm transmission.
With Sustainable Development Goal 7, the United Nations has declared its ambition to ensure access to modern energy for all by 2030. Aside from broad appeals to differentiated responsibilities and ...'greener' technologies, however, the goal leaves significant procedural questions unaddressed. This paper argues that the basic orientation of this approach is problematic, undermining possibilities for progress toward energy justice and equitable development. First, in framing the issue of global energy distribution in broad techno-managerial terms it obscures how particular geographies of energy poverty have been shaped by critical political economic influences. Second, in privileging modern forms of energy and focusing on an end state of universal adoption, over a broader goal of eliminating energy poverty, the approach of SDG7 presents tangible hazards to many of those it seeks to benefit. Using a case study of Sierra Leonean rural cooking energy policy, we demonstrate how the underlying mentality of SDG7 feeds into existing discourses that marginalise producers and users of 'traditional' energy sources, threatening important livelihoods. With such evidence, we argue that for justice in energy policy to be realised holistically, there is a need to question how our knowledge of energy ‘problems’ have emerged to avoid epistemologically autarchic policy positions.
•Examination of the justice issues within the text of Sustainable Development Goal 7.•Investigates how fuelwood is entangled with energy justice issues in Sierra Leone.•Argues energy solutions need to shift away from simple technological fixes.•Energy policy needs to be built on a range of energy knowledges and experiences.
Can part of Africa's current underdevelopment be explained by its slave trades? To explore this question, I use data from shipping records and historical documents reporting slave ethnicities to ...construct estimates of the number of slaves exported from each country during Africa's slave trades. I find a robust negative relationship between the number of slaves exported from a country and current economic performance. To better understand if the relationship is causal, I examine the historical evidence on selection into the slave trades and use instrumental variables. Together the evidence suggests that the slave trades had an adverse effect on economic development.
This study addresses important issues in infant and child mortality in Zimbabwe. The objective of the paper is to determine the impact of maternal, socioeconomic and sanitation variables on infant ...and child mortality. Results show that births of order 6+ with a short preceding interval had the highest risk of infant mortality. The infant mortality risk associated with multiple births was 2.08 times higher relative to singleton births (p<0.001). Socioeconomic variables did not have a distinct impact on infant mortality. Determinants of child mortality were different in relative importance from those of infant mortality. This study supports health policy initiatives to stimulate use of family planning methods to increase birth spacing. These and other results are expected to assist policy makers and programme managers in the child health sector to formulate appropriate strategies to improve the situation of children under 5 in Zimbabwe.
Accurate estimates of aboveground biomass (AGB) strongly depend on the suitability and precision of allometric models. Although additive allometric equations are expected to reduce uncertainties due ...to additivity property between biomass of tree components, methods for developing biomass equations do not comply with the additivity property. This study aimed to evaluate biomass allocation patterns within tree components, and to develop additive allometric equations for Combretum glutinosum and Terminalia laxiflora in West Africa. Sixty trees were destructively sampled and measured for stem, branch and leaf biomass in Sudanian savannas of Burkina Faso. Biomass allocation to stem, branch and leaf was assessed by calculating the biomass fractions for each component. Bivariate relationships between biomass fraction and diameter at beast height (dbh) were further examined. For each biomass component we tested three non-linear allometric equations based on dbh alone, and dbh in combination with height and/or crown diameter as independent variables. Seemingly Unrelated Regressions were used to fit a system of additive biomass allometric equations. Branch biomass accounted for between 60 and 70% of the AGB. Branch mass fraction increased with increasing stem diameter while a reverse trend was observed for leaf and stem mass fractions. The decline in the mass fraction was more pronounced for the leaf than the stem. Additive biomass models developed for the two species exhibited good model fit and performance, with explained variance of 68–89%. The models developed in this study provide a robust estimation of tree biomass components and can be used in Sudanian savannas of West Africa.
•Accurate estimates of aboveground biomass strongly depend on the precision of allometric models.•Methods for developing biomass equations do not comply with the additivity property.•60 trees were destructively sampled and measured for stem, branch and leaf biomass in Sudanian savannas of Burkina Faso.•Biomass allocation to stem, branch and leaf was assessed by calculating the biomass fractions for each component.•Additive allometric equations developed provide a robust estimation of tree biomass components and aboveground biomass.
Major new opportunities abound from energy integration among regions in Africa with the sole aim of reducing transaction costs and with the role of Information Communication Technology (ICT), it ...would take energy from where it is easily affordable to places where it is needed. Given the hullabaloo over the net energy-saving impact of ICT, this study takes on a new perspective, that is, employing household energy consumption, to ascertain the use of ICT by household in accessing energy. The study reconnoiters the degree to which Energy integration among the five regional power pools in Africa can achieve ending energy poverty among regional adherents by means of three measures of energy sustainability, explicitly: energy security, energy equity and environmental sustainability. The study utilizes the Pooled Ordinary Least Squares technique on data from the SSA economies over the period 2000-2019. The study expects the results to help in suggesting the need for the acceleration of ICT development in Africa (Sub-Saharan) nations, given the universal communal mission of sustainable energy consumption.
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