Forest History

Author(s):  
Christopher Conte

Natural and human histories intersect in Africa’s forested regions. Forests of several types cover the continent’s mountains, savannas, and river basins. Most current classifications divide forest by physical structure. Open canopy forests occur in semi-arid regions of western, eastern, and southern Africa, while closed canopy rain forests with large emergent trees cover much of the Congo River basin, the upland forests of Rift Valley escarpments, and the volcanic mountains in eastern and Central Africa. Along the tropical coasts, mangrove forests hug the river estuaries. For much of human history, Africa’s forests have anchored foraging and agrarian societies. In the process of domesticating the landscape through agriculture, Africans modified forests in ways that ranged from large-scale deforestation to forest creation on savanna environments. A boom in forest commodities preceded European colonialism and then continued when foreign governments took formal possession of African territory in the late 19th century. In this context, states ascribed value to forest trees as commodities and so managed them as profitable agricultural crops. Colonial forestry separated people from forests physically and culturally. This fundamental shift in human–forest relations still resonates in postcolonial African countries under the guise of internationally funded forest conservation.

2021 ◽  

Case studies of metropolitan cities in nine African countries from Egypt in the north to three in West and Central Africa, two in East Africa and three in Southern Africa make up the empirical foundation of this publication. The interrelated themes addressed in these chapters the national influence on urban development, the popular dynamics that shape urban development and the global currents on urban development make up its framework. All authors and editors are African, as is the publisher. The only exception is Göran Therborn whose recent book, Cities of Power, served as motivation for this volume. Accordingly, the issue common to all case studies is the often conflictual powers that are exercised by national, global and popular forces in the development of these African cities. Rather than locating the case studies in an exclusively African historical context, the focus is on the trajectories of the postcolonial city (with the important exception of Addis Ababa with a non-colonial history that has granted it a special place in African consciousness). These trajectories enable comparisons with those of postcolonial cities on other continents. This, in turn, highlights the fact that Africa today, the least urbanised continent on an increasingly urbanised globe is in the thick of processes of large-scale urban transformation, illustrated in diverse ways by the case studies that make up the foundation of this publication.


Insects ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 269 ◽  
Author(s):  
Andrew Kalyebi ◽  
Sarina Macfadyen ◽  
Andrew Hulthen ◽  
Patrick Ocitti ◽  
Frances Jacomb ◽  
...  

Cassava (Manihot esculenta Crantz), an important commercial and food security crop in East and Central Africa, continues to be adversely affected by the whitefly Bemisia tabaci. In Uganda, changes in smallholder farming landscapes due to crop rotations can impact pest populations but how these changes affect pest outbreak risk is unknown. We investigated how seasonal changes in land-use have affected B. tabaci population dynamics and its parasitoids. We used a large-scale field experiment to standardize the focal field in terms of cassava age and cultivar, then measured how Bemisia populations responded to surrounding land-use change. Bemisia tabaci Sub-Saharan Africa 1 (SSA1) was identified using molecular diagnostics as the most prevalent species and the same species was also found on surrounding soybean, groundnut, and sesame crops. We found that an increase in the area of cassava in the 3–7-month age range in the landscape resulted in an increase in the abundance of the B. tabaci SSA1 on cassava. There was a negative relationship between the extent of non-crop vegetation in the landscape and parasitism of nymphs suggesting that these parasitoids do not rely on resources in the non-crop patches. The highest abundance of B. tabaci SSA1 nymphs in cassava fields occurred at times when landscapes had large areas of weeds, low to moderate areas of maize, and low areas of banana. Our results can guide the development of land-use strategies that smallholder farmers can employ to manage these pests.


2014 ◽  
Vol 15 (4) ◽  
pp. 820-848
Author(s):  
Pierre-Yves Donzé

Whereas the globalization of medicine since the middle of the 19th century has primarily been approached as the sociopolitical and cultural outcome of imperialism, this article argues that Western big business also played a major role through the worldwide export of standardized medical technologies. It focuses on the expansion of Siemens on the X-ray equipment market in non-Western countries during the first half of the twentieth century. This German multinational enterprise experienced slight growth from the mid-1920s onwards but relied mainly on two markets (Argentina and Brazil). It specialized in providing large-scale equipment to a few urban hospitals and engaged during the 1930s in large-scale hospital development together with local authorities and international organizations in various countries (China, Peru, and Central Africa). However, Siemens had great difficulty in expanding its business to include private doctors and inland outlets, where it faced intense competition from other Western X-ray producers. This paper emphasizes that this shortcoming stemmed from a direct application of the European strategy (high-quality, expensive equipment for hospitals) to non-Western markets, where health systems differed.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1273
Author(s):  
Océane Delandre ◽  
Mathieu Gendrot ◽  
Isabelle Fonta ◽  
Joel Mosnier ◽  
Nicolas Benoit ◽  
...  

Background: Artemisinin-based combination therapy (ACT) was recommended to treat uncomplicated falciparum malaria. Unlike the situation in Asia where resistance to ACT has been reported, artemisinin resistance has not yet emerged in Africa. However, some rare failures with ACT or patients continuing to be parasitaemic on day 3 after ACT treatment have been reported in Africa or in travellers returning from Africa. Three mutations (G50E, R100K, and E107V) in the pfcoronin gene could be responsible for artemisinin resistance in Africa. Methods: The aims of this study were first to determine the prevalence of mutations in the pfcoronin gene in African P. falciparum isolates by Sanger sequencing, by targeting the 874 samples collected from patients hospitalised in France after returning from endemic areas in Africa between 2018 and 2019, and secondly to evaluate their association with in vitro reduced susceptibility to standard quinoline antimalarial drugs, including chloroquine, quinine, mefloquine, desethylamodiaquine, lumefantrine, piperaquine, and pyronaridine. Results: The three mutations in the pfcoronin gene (50E, 100K, and 107V) were not detected in the 874 P. falciparum isolates. Current data show that another polymorphism (P76S) is present in many countries of West Africa (mean prevalence of 20.7%) and Central Africa (11.9%) and, rarely, in East Africa (4.2%). This mutation does not appear to be predictive of in vitro reduced susceptibility to quinolines, including artemisinin derivative partners in ACT such as amodiaquine, lumefantrine, piperaquine, pyronaridine, and mefloquine. Another mutation (V62M) was identified at low prevalence (overall prevalence of 1%). Conclusions: The 76S mutation is present in many African countries with a prevalence above 10%. It is reassuring that this mutation does not confer in vitro resistance to ACT partners.


Author(s):  
Annalisa Bergna ◽  
Carla Della Ventura ◽  
Rossella Marzo ◽  
Massimo Ciccozzi ◽  
Massimo Galli ◽  
...  

In order to reconstruct the origin and pathways of variola virus (VARV) dispersion, we analyzed 47 VARV isolates available in public databases and their SNPs. The mean substitution rate of the whole genomes was 9.41x10-6 (95%HPD:8.5-11.3x10-6) substitutions/site/year. The time of the tree root was estimated to be a mean 68 years (95%HPD:60.5–75.9). The phylogeographical analysis showed that the Far East and India were the most probable locations of the tree root and of the inner nodes, respectively, whereas for the outer nodes it corresponded to the sampling locations. The Bayesian Skyline plot showed that the effective number of infections started to grow exponentially in 1915-1920, peaked in the 1940s, and then decreased to zero. Our results suggests that the VARV major strains circulating between 1940s-1970s probably shared a common ancestor originated in the Far East; subsequently moved to India, which became the center of its dispersion to eastern and southern Africa, and then to central Africa and the Middle East, probably following the movements of people between south-eastern Asia and the other places with a common colonial history. These findings may help to explain the controversial reconstructions of the history of VARV obtained using long- and short- term calibrations.


Plant Disease ◽  
1999 ◽  
Vol 83 (4) ◽  
pp. 398-398 ◽  
Author(s):  
F. O. Ogbe ◽  
G. I. Atiri ◽  
D. Robinson ◽  
S. Winter ◽  
A. G. O. Dixon ◽  
...  

Cassava (Manihot esculenta Crantz) is an important food crop in sub-Saharan Africa. One of the major production constraints is cassava mosaic disease caused by African cassava mosaic (ACMV) and East African cassava mosaic (EACMV) begomoviruses. ACMV is widespread in its distribution, occurring throughout West and Central Africa and in some eastern and southern African countries. In contrast, EACMV has been reported to occur mainly in more easterly areas, particularly in coastal Kenya and Tanzania, Malawi, and Madagascar. In 1997, a survey was conducted in Nigeria to determine the distribution of ACMV and its strains. Samples from 225 cassava plants showing mosaic symptoms were tested with ACMV monoclonal antibodies (MAbs) in triple antibody sandwich enzyme-linked immunosorbent assay (1). Three samples reacted strongly with MAbs that could detect both ACMV and EACMV. One of them did not react with ACMV-specific MAbs while the other two reacted weakly with such MAbs. With polymerase chain reaction (2), the presence of EACMV and a mixture of EACMV and ACMV in the respective samples was confirmed. These samples were collected from two villages: Ogbena in Kwara State and Akamkpa in Cross River State. Co-infection of some cassava varieties with ACMV and EACMV leads to severe symptoms. More importantly, a strain of mosaic geminivirus known as Uganda variant arose from recombination between the two viruses (2). This report provides evidence for the presence of EACMV in West Africa. References: (1) J. E. Thomas et al. J. Gen. Virol. 67:2739, 1986. (2) X. Zhou et al. J. Gen. Virol. 78:2101, 1997.


2020 ◽  
Author(s):  
Cheryl Case Johnson ◽  
Melissa Neuman ◽  
Peter MacPherson ◽  
Augustine Choko ◽  
Caitlin Quinn ◽  
...  

Abstract Background Many southern African countries are nearing the global goal to diagnose 90% of people with HIV by 2020. In 2016, 84% and 86% of people with HIV knew their status in Malawi and Zimbabwe respectively. Despite this progress, gaps remain, particularly among men (≥25 years). We investigated awareness, use and willingness to HIV self-test (HIVST) prior to large scale implementation and explored sociodemographic associations. Methods We pooled responses from two of the first cross-sectional Demographic Health Surveys to include HIVST questions: Malawi and Zimbabwe in 2015-16. Sociodemographic factors and sexual risk behaviours associated with previously testing for HIV, and awareness, past use and future willingness to self-test were investigated using univariable and multivariable logistic regression, adjusting for the sample design and limiting analysis to participants with completed questionnaire and a valid HIV result. Analysis of willingness to self-test was restricted to Zimbabwean men, as Malawians and women were not asked this question. Results Of 31 385 individuals, the proportion never-tested was higher for men (31.2%) than women (16.5%), p<0.001. For men, having ever tested increased with age. Past use and awareness of HIVST was very low, 1.2% and 12.6% respectively. Awareness was lower among women than men (9.1% vs 15.3%, adjusted odds ratio (aOR)=1.55; 95% confidence interval [CI]: 1.37-1.75), and at younger ages, and lower education and literacy levels. Willingness to self-test among Zimbabwean men was high (84.5%), with having previously tested for HIV, high sexual risk, and being ≥25 years associated with greater willingness. Wealthier men had greater awareness of HIVST than poorer men (p<0.001). Men at higher HIV-related sexual risk, compared to men at lower HIV-related sexual risk, had the greatest willingness to self-test (aOR=3.74; 95%CI: 1.39-10.03, p<0.009).Conclusions In 2015-16 many Malawian and Zimbabwean men had never tested for HIV. Despite low awareness and minimal HIVST experience at that time, willingness to self-test was high among Zimbabwean men, especially in older men with moderate to high HIV-related sexual risk. These data provide a valuable baseline against which to investigate population-level uptake of HIVST as programmes scale-up. Programmes introducing, or planning to introduce HIVST, should consider including questions in population-based surveys.


Author(s):  
Melinda Smale ◽  
◽  
Veronique Theriault ◽  
Ryan Vroegindewey ◽  
◽  
...  

Mali’s population is experiencing lifestyle and dietary changes that are driven in part by urbanisation and income growth. Utilising two large-scale datasets, we bring new empirical evidence regarding whether Malians are shifting toward highly processed foods, meals purchased away from home, and sugary foods. We find that on-farm production represents only 25% of the food consumed by rural households during the hungry season, and 36% after harvest. Processed food shares are greater in urban (60%) than in rural areas (48%), and considerably higher overall than those reported for Eastern and Southern Africa, but with a lower portion of highly processed foods and negligible shares of meals consumed outside the home. Average household dietary diversity scores are higher in urban than in rural areas. Women’s and household diet diversity varies by season in both locations. About half of farm women interviewed did not meet minimum adequate dietary diversity during the lean season.


2017 ◽  
Vol 13 (11) ◽  
pp. 92
Author(s):  
Mampeta Wabasa Salomon

In the Democratic Republic of the Congo (DRC), the protectionist conservatism influenced by colonialism, which exploited African countries for the prosperity of the colonizing countries, still has a high visibility in the Salonga National Park (PNS). If, in theory, the Central Africans seem to free themselves from the colonial powers on their land, in practice they are still there. The hostility of settlers who have become neo-colonists to the development of Central Africa remains intact, he adds (Ndinga, 2003). This reflects a "logic from above" that has disregarded local values. Yet, in the era of sustainable development and globalization, African protected areas appear to be essential tools for States to reposition themselves in a complex set of actors with the aim of capturing and using the new environmental rent (Giraut, Guyot, & Houssay-Holzschuch, 2003). This is a "bottom-up logic", placing people at the heart of all activities and aiming to reorganize their long-term relationships with the environment. From these two logics, a third "logic from the other side" emerges, reflecting a collective awareness of the fragility of the planet. The restoration of the rights of Africans in the various national frameworks constitutes a major challenge for the contemporary management of African protected areas. Because the protected areas inherited from the different colonial systems must accompany the change in management methods and the redefinition of their functions in order to better serve the local community in the long-term.


2021 ◽  
Author(s):  
Javier Perez-Saez ◽  
Justin Lessler ◽  
Elizabeth C. Lee ◽  
Francisco J. Luquero ◽  
Espoir B. Malembaka ◽  
...  

Background Cholera remains a major threat in Sub-Saharan Africa (SSA) where some of the highest case fatality risks are reported. Knowing in what months and where cholera tends to occur across the continent can aid in improving efforts to eliminate cholera as a public health concern; though largely due to lack of unified large-scale datasets, no continent-wide estimates exist. In this study we aim to estimate cholera seasonality across SSA. Methods We leverage the Global Task Force on Cholera Control (GTFCC) global cholera database with statistical models to synthesize data across spatial and temporal scale in order to infer the seasonality of excess suspected cholera occurrence in SSA. We developed a Bayesian statistical model to infer the monthly risk of excess cholera at the first and/or second administrative levels. Seasonality patterns were then grouped into spatial clusters. Finally, we studied the association between seasonality estimates and hydro-climatic variables. Findings The majority of studied countries (24/34) have seasonal patterns in excess cholera, corresponding to approximately 85% of the SSA population. Most countries (19/24) also had sub-national differences in seasonality patterns, with strong differences in seasonality strength between regions. Seasonality patterns clustered into two macro-regions (West Africa and the Sahel vs. Eastern and Southern Africa), which were composed of sub-regional clusters with varying degrees of seasonality. Exploratory association analysis found most consistent and positive correlations between cholera seasonality and precipitation, and to a lesser extent with temperature and flooding. Interpretation Widespread cholera seasonality in SSA offers opportunities for intervention planning. Further studies are needed to study the association between cholera and climate. Funding The NASA Applied Sciences Program and the Bill and Melinda Gates Foundation.


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