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Sample records for benin west africa

  1. Issues of Sustainability of Coastal Groundwater Resources: Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Andrew D. Mullen

    2010-08-01

    Full Text Available The largest city in Benin, West Africa (Cotonou, is reliant upon groundwater for its public water supply. This groundwater is derived from the Godomey well field which is located approximately 5 Km north of the coast of the Atlantic Ocean and in close proximity to Lake Nokoue—a shallow lake containing water with elevated concentration of chloride and other elements. Historical data indicate increased chloride concentration in a number of wells nearest to the lake, with unknown contribution from groundwater encroachment from the coastal area. Hence, there is substantial interest in better characterizing this groundwater system for the purpose of determining appropriate management practices and degree of sustainability. Among the efforts attempted to date are a series of numerical models ranging from assessment of flow to a recent effort to include density-dependent transport from the lake. In addition, substantial field characterization has been pursued including assessment of shallow water chemistry along the region of the coastal lagoon and border of the lake, characterization of hydraulic response to pumpage in the aquifer system, estimation of the distribution of electrical resistivity with depth along the coastal lagoons, and installation of multi-level piezometers at seven locations in the lake. When integrated across methods, these numerical and field results indicate that the lake remains a primary concern in terms of a source of salinity in the aquifer. Further, the coastal region appears to be more complex than previously suggested and may represent a future source of salt-water encroachment as suggested by current presence of saline waters at relatively shallow depths along the coast. Finally, hydraulic testing suggests that both natural and pumping-based fluctuations in water levels are present in this system. Substantial additional characterization and modeling efforts may provide a significantly greater understanding of the

  2. Genetic nature of yams (Dioscorea sp.) domesticated by farmers in Benin (West Africa)

    OpenAIRE

    Scarcelli, Nora; Tostain, Serge; Mariac, Cédric; Agbangla, C.; Da, O.; Berthaud, Julien; Pham, Jean-Louis

    2006-01-01

    'Domestication' is a traditional farmers' practice reported for yams (Dioscorea sp.) in Benin (West Africa). It involves introducing 'spontaneous' (naturally occurring) yams, supposedly wild (D. abyssinica and D. praehensilis), in varieties of the D. cayenensis-D. rotundata cultivated species complex. In this study, we established the genetic nature of 'predomesticated' yam plants using the amplified fragment length polymorphism (AFLP) technique. A total of 213 accessions, consisting of 32 pr...

  3. Evaluation of global rainfall Measurement for Hydrological Applications in West Africa : sensitivity tests in Benin

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    Viarre, J.; Gosset, M.; Peugeot, C.

    2011-12-01

    We carried out an evaluation of currently available -real time or post-calibrated- rainfall products in West Africa. The work is oriented towards highlighting their skills and relevance from the view point of a hydrological end-user. The study is based on the densily instrumented meso-scale basins from the AMMA-CATCH hydrometeorological observing system. On these sites long term observations of the various term of the continental water budget and hydrological processes studies have been carried out for more than a decade. We focus here on the upper Oueme basin site in Benin (Sudanese climate - 1200 mm annual rainfall). A distributed hydrological model, developed in this framework is used to illustrate the effects of satellite based rainfall errors or uncertainty on the simulated outflow. Non linearities cause the rainfall bias to be enhanced through propagation in the model, leading to strong biases in the outflow. In addition to the biases the model response is very sensitive to the distortion in the rainfall intensities probability distribution, that some rainfall products exhibit. The AMMA-CATCH densified gages networks and hydrometeorological measurements will be integrated in the MeghaTropiques ground validation plan and used to asses the quality of MT products at the one degree one daily scale and below.

  4. Precipitation chemistry and wet deposition in a remote wet savanna site in West Africa: Djougou (Benin)

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    Akpo, A. B.; Galy-Lacaux, C.; Laouali, D.; Delon, C.; Liousse, C.; Adon, M.; Gardrat, E.; Mariscal, A.; Darakpa, C.

    2015-08-01

    In the framework of the IDAF (IGAC/DEBITS/AFrica) international program, this study aims to study the chemical composition of precipitation and associated wet deposition at the rural site of Djougou in Benin, representative of a West and Central African wet savanna. Five hundred and thirty rainfall samples were collected at Djougou, Benin, from July 2005 to December 2009 to provide a unique database. The chemical composition of precipitation was analyzed for inorganic (Ca2+, Mg2+, Na+, NH4+, K+, NO3-, Cl-, SO42-) and organic (HCOO-, CH3COO-, C2H5COO-, C2O42-) ions, using ion chromatography. The 530 collected rain events represent a total of 5706.1 mm of rainfall compared to the measured pluviometry 6138.9 mm, indicating that the collection efficiency is about 93%. The order of total annual loading rates for soluble cations is NH4+ > Ca2+ > Mg2+ > K+. For soluble anions the order of loading is carbonates > HCOO- > NO3- > CH3COO- > SO4,SUP>2- > Cl- > C2O42- > C2H5COO-. In the wet savanna of Djougou, 86% of the measured pH values range between 4.7 and 5.7 with a median pH of 5.19, corresponding to a VWM (Volume Weighed Mean) H+ concentration of 6.46 μeq·L-1. This acidity results from a mixture of mineral and organic acids. The annual sea salt contribution was computed for K+, Mg2+, Ca2+ and SO42- and represents 4.2% of K+, 41% of Mg2+, 1.3% of Ca2+, and 7.4% of SO42-. These results show that K+, Ca2+, SO42-, and Mg2+ were mainly of non-marine origin. The marine contribution is estimated at 9%. The results of the chemical composition of rainwater of Djougou indicates that, except for the carbonates, ammonium has the highest VWM concentration (14.3 μeq·L-1) and nitrate concentration is 8.2 μeq·L-1. The distribution of monthly VWM concentration for all ions is computed and shows the highest values during the dry season, comparing to the wet season. Identified nitrogenous compound sources (NOx and NH3) are domestic animals, natural emissions from savanna soils

  5. Assessment of the Contamination of Some Foodstuffs by Escherichia coli O157 in Benin, West Africa

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    Honoré Sourou Bankole

    2014-01-01

    Full Text Available Escherichia coli O157 is a pathogenic bacterium causing haemorrhagic colitis. It represents a serious public health problem in Northern America and Europe, which can plague Africa. Most cases of mentioned poisoning were related to contaminated meat products and vegetables. The present work aimed to estimate the prevalence of E. coli O157 in meat and vegetables in Benin. For this purpose, 6 lots of faeces samples from pigs and 8 from cattle were collected at the farms on the outskirts of Cotonou. Similarly, 20 samples of carcasses, 20 samples of intestines and stomach, and 20 surfaces samples of slaughtering equipment were taken. Vegetables and environment materials in gardens have also been sampled for 84 samples. Bacteriological analyses revealed a percentage of contamination of 50% for pig faeces and 25% for cattle ones. All the meats from stalling parks have been contaminated by this bacterium. For vegetables, 14.6% of samples were contaminated by E. coli O157. The presence of this pathovar in animal breeding and slaughtering environment and in the gardens shows that Benin is not aware of the risks of foodborne illness associated with the consumption of contaminated products. Therefore, it urges including that germ in a systematic search during safety control of food products in Benin.

  6. Insect fauna associated with Anacardium occidentale (Sapindales: Anacardiaceae) in Benin, West Africa.

    OpenAIRE

    Agboton, C.; Onzo, A.; Ouessou, F. I.; Goergen, G.; Vidal, S.; Tamò, M.

    2014-01-01

    Cashew, Anacardium occidentale L. (Sapindales: Anacardiaceae), is an important cash crop in Benin. However, its production is threatened by several biotic factors, especially insects. In Benin, very few studies have focused on insects and just listed species commonly found on cashew worldwide. The present investigation fills this gap by presenting an exhaustive inventory of insect species associated with this crop in the country. The survey was carried out from September 2009 to August 2010 i...

  7. Buruli ulcer disease prevalence in Benin, West Africa: Associations with land use/cover and the identification of disease clusters

    Science.gov (United States)

    Wagner, T.; Benbow, M.E.; Brenden, T.O.; Qi, J.; Johnson, R.C.

    2008-01-01

    Background: Buruli ulcer (BU) disease, caused by infection with the environmental mycobacterium M. ulcerans, is an emerging infectious disease in many tropical and sub-tropical countries. Although vectors and modes of transmission remain unknown, it is hypothesized that the transmission of BU disease is associated with human activities in or around aquatic environments, and that characteristics of the landscape (e.g., land use/cover) play a role in mediating BU disease. Several studies performed at relatively small spatial scales (e.g., within a single village or region of a country) support these hypotheses; however, if BU disease is associated with land use/cover characteristics, either through spatial constraints on vector-host dynamics or by mediating human activities, then large-scale (i.e., country-wide) associations should also emerge. The objectives of this study were to (1) investigate associations between BU disease prevalence in villages in Benin, West Africa and surrounding land use/cover patterns and other map-based characteristics, and (2) identify areas with greater and lower than expected prevalence rates (i.e., disease clusters) to assist with the development of prevention and control programs. Results: Our landscape-based models identified low elevation, rural villages surrounded by forest land cover, and located in drainage basins with variable wetness patterns as being associated with higher BU disease prevalence rates. We also identified five spatial disease clusters. Three of the five clusters contained villages with greater than expected prevalence rates and two clusters contained villages with lower than expected prevalence rates. Those villages with greater than expected BU disease prevalence rates spanned a fairly narrow region of south-central Benin. Conclusion: Our analyses suggest that interactions between natural land cover and human alterations to the landscape likely play a role in the dynamics of BU disease. For example

  8. Bendiocarb, a potential alternative against pyrethroid resistant Anopheles gambiae in Benin, West Africa

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    Irish Seth

    2010-07-01

    Full Text Available Abstract Background Anopheles gambiae, the main malaria vector in Benin has developed high level of resistance to pyrethroid insecticides, which is a serious concern to the future use of long-lasting insecticidal nets (LLIN and indoor residual spraying (IRS. In this context, one of the pathways available for malaria vector control would be to investigate alternative classes of insecticides with different mode of action than that of pyrethroids. The goal of this study was to evaluate under field conditions the efficacy of a carbamate (bendiocarb and an organophosphate (fenitrothion against pyrethroid-resistant An. gambiae s.s. Methods Wild populations and females from laboratory colonies of five days old An. gambiae were bio-assayed during this study. Two pyrethroids (deltamethrin and alphacypermethrin, an organophosphate (fenitrothion, a carbamate (bendiocarb and a mixture of an organophosphate (chlorpyriphos + a pyrethroid deltamethrin were compared in experimental huts as IRS treatments. Insecticides were applied in the huts using a hand-operated compression sprayer. The deterrency, exophily, blood feeding rate and mortality induced by these insecticides against An. gambiae were compared to the untreated control huts. Results Deltamethrin, alphacypermethrin and bendiocarb treatment significantly reduced mosquito entry into the huts (p An. gambiae (in the first month and 77.8% (in the fourth month. Bendiocarb and the mixture chlorpyriphos/deltamethrin mortality rates ranged from 97.9 to 100% the first month and 77.7-88% the third month respectively. Conclusion After four months, fenitrothion, bendiocarb and the mixture chlorpyriphos/deltamethrin performed effectively against pyrethroid-resistant Anopheles. These results showed that bendiocarb could be recommended as an effective insecticide for use in IRS operations in Benin, particularly as the mixture chlorpyriphos/deltamethrin does not have WHOPES authorization and complaints were mentioned

  9. Factors in the Effective Utilization of a LANDSAT Related Inventory in West Africa. [resource management in onchocerciasis-free Benin, Upper Volta, and Ghana

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    Hall, L.

    1982-01-01

    A comprehensive LANDSAT related resource inventory was performed in parts of Ghana, Benin, and Upper Volta to determine resource development potential in areas freed of the disease onchocerciasis. The ultimate success of the project lies in the effective use of the data by host country personnel in resource development projects. This requires project follow-through, adequate training of regional counterparts, and integration of the data into an easily used framework. Present levels of support systems and technical expertise in West Africa indicate that an automated system for natural resource data is not currently appropriate. Suggestions for the greater implementation of such inventories are explored.

  10. Climatic variability and spatial distribution of herbaceous fodders in the Sudanian zone of Benin (West Africa.

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    Myrèse C. Ahoudji

    2016-01-01

    Full Text Available This study focused on future spatial distributions of Andropogon gayanus, Loxodera ledermanii and Alysicarpus ovalifolius regarding bioclimatic variables in the Sudanian zone of Benin, particularly in the W Biosphere Reserve (WBR. These species were selected according to their importance for animals feed and the intensification of exploitation pressure induced change in their natural spatial distribution. Twenty (20 bioclimatic variables were tested and variables with high auto-correlation values were eliminated. Then, we retained seven climatic variables for the model. A MaxEnt (Maximum Entropy method was used to identify all climatic factors which determined the spatial distribution of the three species. Spatial distribution showed for Andropogon gayanus, a regression of high area distribution in detriment of low and moderate areas. The same trend was observed for Loxodera ledermannii spatial distribution. For Alysicarpus ovalifolius, currently area with moderate and low distribution were the most represented but map showed in 2050 that area with high distribution increased. We can deduce that without bioclimatic variables, others factors such as: biotic interactions, dispersion constraints, anthropic pressure, human activities and another historic factor determined spatial distribution of species. Modeling techniques that require only presence data are therefore extremely valuable.

  11. Response of the Bight of Benin (Gulf of Guinea, West Africa) coastline to anthropogenic and natural forcing, Part1: Wave climate variability and impacts on the longshore sediment transport

    NARCIS (Netherlands)

    Almar, R.; Kestenare, E.; Reyns, J.; Jouanno, J; Anthony, E.; Laibi, R.; Hemer, M.; Du Penhoat, Y.; Ranasinghe, R.W.M.R.J.

    2015-01-01

    The short, medium and long-term evolution of the sandy coastline of the Bight of Benin in the Gulf of Guinea, West Africa, has become a major regional focal point due to the rapid socio-economic development that is occurring in the region, including rapid urbanization and a sharp increase in harbor-

  12. Mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in Southern Benin (West Africa).

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    Lingenfelser, Andre; Rydzanicz, Katarzyna; Kaiser, Achim; Becker, Norbert

    2010-01-01

    This study aims at an integrated vector management (IVM) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. In the first step, the mosquito species composition fauna of southern Benin was studied using standard entomological procedures in natural and man-made habitats. Altogether, 24 species belonging to 6 genera of mosquitoes Aedes, Anopheles, Culex, Mansonia, Uranotaenia, Ficalbia were recorded. Five species, Cx. thalassius, Cx. nebulosus, Cx. perfuscus, Cx. pocilipes and Fi. mediolineata are described the first time for Benin. The local mosquito species showed high susceptibility to a Bacillus sphaericus formulation (VectoLex(R) WDG ) in a standardized field test. A dosage of 1 g/m(2) was effective to achieve 100 percent mortality rate for Cx. quinquefasciatus late instar larvae in a sewage habitat, with a residual effect of up to 7 days. After more than 1 year of baseline data collection, operational larviciding with B. thuringiensis var. israelensis and B. sphaericus was commenced in 2006 in selected areas. Microbial insecticides products for larval control show great potential within IVM programmes and may augment control efforts against adult insects, such as the use of insecticide-treated bed nets or indoor wall spraying in many parts of Africa.

  13. Mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in Southern Benin (West Africa).

    Science.gov (United States)

    Lingenfelser, Andre; Rydzanicz, Katarzyna; Kaiser, Achim; Becker, Norbert

    2010-01-01

    This study aims at an integrated vector management (IVM) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. In the first step, the mosquito species composition fauna of southern Benin was studied using standard entomological procedures in natural and man-made habitats. Altogether, 24 species belonging to 6 genera of mosquitoes Aedes, Anopheles, Culex, Mansonia, Uranotaenia, Ficalbia were recorded. Five species, Cx. thalassius, Cx. nebulosus, Cx. perfuscus, Cx. pocilipes and Fi. mediolineata are described the first time for Benin. The local mosquito species showed high susceptibility to a Bacillus sphaericus formulation (VectoLex(R) WDG ) in a standardized field test. A dosage of 1 g/m(2) was effective to achieve 100 percent mortality rate for Cx. quinquefasciatus late instar larvae in a sewage habitat, with a residual effect of up to 7 days. After more than 1 year of baseline data collection, operational larviciding with B. thuringiensis var. israelensis and B. sphaericus was commenced in 2006 in selected areas. Microbial insecticides products for larval control show great potential within IVM programmes and may augment control efforts against adult insects, such as the use of insecticide-treated bed nets or indoor wall spraying in many parts of Africa. PMID:20684480

  14. Contribution to the Analysis Cost/Benefit of Scenarios to Control Tsetse and Trypanosomiasis in West Africa (Data Study Area in Benin)

    International Nuclear Information System (INIS)

    Trypanosomiasis and animal sleeping sickness is a major constraint for Africa south of Sahara. Nearly a century of struggle was not enough to contain tsetse infestations or reduce the impact of Trypanosomiasis in Africa. So that the socioeconomic development of third of the continent is severely compromised by the consequences of this debilitating often fatal disease that affects humans and animals. It is painful to note that the country's poorest continent through a crisis period (armed conflict, population movements) are most severely affected by the sleeping sickness making interventions of medical teams difficult and dangerous. Sixty (60) million men, women and children in 22 of 36 countries in sub-Saharan Africa live under the threat of sleeping sickness. About half a million men are affected by sleeping sickness. 45,000 new cases were recorded according to WHO in 1999. Forty four (44) million cattle besides other domestic animals are in infested areas of tsetse flies. The disease causes a loss of 3 million cattle a year, a loss of 26% milk yield, a 50% reduction in the number of herds in areas with high agricultural potential (PLTA, 1999). This report has been prepared to provide the International Atomic Energy Agency (IAEA) data on the various study area in Benin for a cost / benefit analysis of any program against tsetse flies and trypanosomiasis in Sudanian and Sudanian Sahel of West Africa. The study area located in Benin covers the departments of Alibori and Borgou. After presenting general information on Benin, this report focuses on: - The evolution of the human population in the study area, - The health situation, - The size and productivity of livestock, - The development achievements of major crops - Natural resources and soil quality. In conclusion, it was noted the positive impact of a regional program to fight against Tsetse and Trypanosomiasis based on the integrated use of different control methods non pollutant to the environment (traps and

  15. Insecticide residues in bats along a land use-gradient dominated by cotton cultivation in northern Benin, West Africa.

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    Stechert, Christin; Kolb, Marit; Bahadir, Müfit; Djossa, Bruno A; Fahr, Jakob

    2014-01-01

    Many regions in Africa are currently being converted from subsistence to cash crop farming such as cotton. Agricultural intensification is usually accompanied by increased use of pesticides, which can have an impact on non-target organisms. Bats are particularly sensitive to insecticide loads while providing substantial ecosystem services as predators of herbivorous insects. In this study, pesticide residues in bats in a landscape in northern Benin were investigated, which spanned a land use gradient from an agricultural zone dominated by cotton farms, through a buffer zone, and into a national park. Insecticides used in cotton cultivation, such as endosulfan, chlorpyrifos, flubendiamide, and spirotetramat, as well as persistent insecticides such as bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), lindane, and aldrine, were analysed. Insecticide residues detected in bats comprised DDT, endosulfan, and their corresponding transformation products. Maximum concentrations in the sampled bats were 11.2 mg/kg lipid of p,p'-DDE (median: 0.0136 mg/kg lipid) and 0.797 mg/kg lipid of β-endosulfan (median: below detection limit [DL]). While insecticide concentrations were below lethal concentrations our data suggest that DDT had probably been recently used in the study region, and larger scale use would pose an increased risk for bat populations due to the high biomagnification of DDT.

  16. Dynamics of insecticide resistance in malaria vectors in Benin: first evidence of the presence of L1014S kdr mutation in Anopheles gambiae from West Africa

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    Ranson Hilary

    2011-09-01

    Full Text Available Abstract Background Insecticide resistance monitoring is essential to help national programmers to implement more effective and sustainable malaria control strategies in endemic countries. This study reported the spatial and seasonal variations of insecticide resistance in malaria vectors in Benin, West Africa. Methods Anopheles gambiae s.l populations were collected from October 2008 to June 2010 in four sites selected on the basis of different use of insecticides and environment. WHO susceptibility tests were carried out to detect resistance to DDT, fenitrothion, bendiocarb, permethrin and deltamethrin. The synergist piperonyl butoxide was used to assess the role of non-target site mechanisms in pyrethroid resistance. Anopheles gambiae mosquitoes were identified to species and to molecular M and S forms using PCR techniques. Molecular and biochemical assays were carried out to determine kdr and Ace.1R allelic frequencies and activity of the detoxification enzymes. Results Throughout the surveys very high levels of mortality to bendiocarb and fenitrothion were observed in An. gambiae s.l. populations. However, high frequencies of resistance to DDT and pyrethroids were seen in both M and S form of An. gambiae s.s. and Anopheles arabiensis. PBO increased the toxicity of permethrin and restored almost full susceptibility to deltamethrin. Anopheles gambiae s.l. mosquitoes from Cotonou and Malanville showed higher oxidase activity compared to the Kisumu susceptible strain in 2009, whereas the esterase activity was higher in the mosquitoes from Bohicon in both 2008 and 2009. A high frequency of 1014F kdr allele was initially showed in An. gambiae from Cotonou and Tori-Bossito whereas it increased in mosquitoes from Bohicon and Malanville during the second year. For the first time the L1014S kdr mutation was found in An. arabiensis in Benin. The ace.1R mutation was almost absent in An. gambiae s.l. Conclusion Pyrethroid and DDT resistance is

  17. Implications of future climate change on agricultural production in tropical West Africa: evidence from the Republic of Benin

    OpenAIRE

    Awoye, Oyémonbadé Hervé Rodrigue

    2015-01-01

    Environmental interlinked problems such as human-induced land cover change, water scarcity, loss in soil fertility, and anthropogenic climate change are expected to affect the viability of agriculture and increase food insecurity in many developing countries. Climate change is certainly the most serious of these challenges for the twenty-first century. The poorest regions of the world – tropical West Africa included – are the most vulnerable due to their high dependence on climate and weather...

  18. The influence of storage practices on aflatoxin contamination in maize in four agroecological zones of Benin, west Africa.

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    Hell; Cardwell; Setamou; Poehling

    2000-10-15

    Aflatoxin level in 300 farmers' stores in four agro-ecological zones in Benin, a west African coastal country, were determined over a period of 2 years. At sampling a questionnaire was used to evaluate maize storage practices. Farmers were asked what storage structure they used, their storage form, storage period, pest problems in storage and what was done against them. Beninese farmers often changed their storage structures during the storage period, transfering the maize from a drying or temporary store to a more durable one. Most of the farmers complained about insects damaging stored maize. Often, storage or cotton insecticides were utilized against these pests. Regression analysis identified those factors that were associated with increased or reduced aflatoxin.Maize samples in the southern Guinea and Sudan savannas were associated with higher aflatoxin levels and the forest/savanna mosaic was related to lower toxin levels. Factors associated with higher aflatoxin were: storage for 3-5 months, insect damage and use of Khaya senegalensis-bark or other local plants as storage protectants. Depending on the agroecological zone, storage structures that had a higher risk of aflatoxin development were the "Ago", the "Secco", the "Zingo" or storing under or on top of the roof of the house. Lower aflatoxin levels were related to the use of storage or cotton insecticides, mechanical means or smoke to protect against pests or cleaning of stores before loading them with the new harvest. Fewer aflatoxins were found when maize was stored in the "Ago" made from bamboo or when bags were used as secondary storage containers. PMID:10880814

  19. Integration of Optical and Synthetic Aperture Radar Imagery for Improving Crop Mapping in Northwestern Benin, West Africa

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    Gerald Forkuor

    2014-07-01

    Full Text Available Crop mapping in West Africa is challenging, due to the unavailability of adequate satellite images (as a result of excessive cloud cover, small agricultural fields and a heterogeneous landscape. To address this challenge, we integrated high spatial resolution multi-temporal optical (RapidEye and dual polarized (VV/VH SAR (TerraSAR-X data to map crops and crop groups in northwestern Benin using the random forest classification algorithm. The overall goal was to ascertain the contribution of the SAR data to crop mapping in the region. A per-pixel classification result was overlaid with vector field boundaries derived from image segmentation, and a crop type was determined for each field based on the modal class within the field. A per-field accuracy assessment was conducted by comparing the final classification result with reference data derived from a field campaign. Results indicate that the integration of RapidEye and TerraSAR-X data improved classification accuracy by 10%–15% over the use of RapidEye only. The VV polarization was found to better discriminate crop types than the VH polarization. The research has shown that if optical and SAR data are available for the whole cropping season, classification accuracies of up to 75% are achievable.

  20. Cotton fertilization using PGPR Bacillus amyloliquefaciens FZB42 and compost: Impact on insect density and cotton yield in North Benin, West Africa

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    Thiery B. Charles Alavo

    2015-12-01

    Full Text Available This work has compared the effects of the biofertilizer Bacillus amyloliquefaciens FZB42 with that of compost for cotton production. The population dynamics of pests and predators have been studied in order to check whether the use of both fertilization materials can contribute to pest management in cotton. Three treatments were considered: (i dressing of seeds in rhizobacteria suspension, (ii introduction of rhizobacterial suspension directly in the pocket, same time with the seeds, and (iii fertilization with compost. The study was carried out in northwest Benin (West Africa. Results showed that cotton aphids, Aphis gossypii, pink bollworm, Pectinophora gossypiella, leaf roller, Sylepta derogata, and cotton bugs, Dysdercus sp. are the major insect pests encountered in the experimental plots. Cotton bollworm, Helicoverpa armigera, was present but under the economic threshold. The coccinellid predators, Cheilomenes spp., occurred in the experimental plots and almost suppressed aphid proliferation. Other natural enemies such as chrysopids and ant species also occurred and probably contributed to maintain the cotton bollworm under the economic threshold. The treatment with seeds dressed with the rhizobacteria suspension yielded 39% more cotton compared to the compost fertilization. The use of both fertilization materials without application of chemicals can contribute to pest management in cotton.

  1. Diversity patterns of indigenous arbuscular mycorrhizal fungi associated with rhizosphere of cowpea (Vigna unguiculata (L.) Walp.) in Benin, West Africa

    OpenAIRE

    Johnson, J. M.; Houngnandan, P.; A. Kane; Sanon, K. B.; Neyra, Marc

    2013-01-01

    Assessment of diversity and understanding factors underlying species distribution are fundamental themes in ecology. However, the diversity of native arbuscular mycorrhizal fungi (AMF) species in African tropical agro-ecosystems remains weakly known. This research was carried out to assess the morphological diversity of indigenous AMF species associated with rhizosphere of cowpea (Vigna unguiculata (L) Walp.) in different agro-ecological zones (AEZ) of Benin and to examine the effects of soil...

  2. Characterization of Potential Plant Growth Promoting Rhizobacteria Isolated from Maize (Zea mays L. in Central and Northern Benin (West Africa

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    Nadège A. Agbodjato

    2015-01-01

    Full Text Available Our study aims to characterize Plant Growth Promoting Rhizobacteria (PGPR isolated from maize roots in five agroecological zones of central and northern Benin. Sixty samples were collected at the rate of four samples per village and three villages per agroecological zone. Rhizobacteria strains were isolated from these samples and biochemically characterized. These strains were analyzed for some of their PGPR traits like ammonia production and hydrogen cyanide following conventional methods. Microbiological investigation of these samples has shown that maize rhizospheres in central and northern Benin contain a high diversity of microorganisms. A total of nine species of maize Plant Growth Promoting Rhizobacteria were identified. Those PGPR include five Bacillus species (B. polymyxa, B. pantothenticus, B. anthracis, B. thuringiensis, and B. circulans, three Pseudomonas species (P. cichorii, P. putida, and P. syringae, and Serratia marcescens. The microbial diversity does not depend on the soil types. The microbial density, generally high, varies according to both soil types and agroecological zones. All Serratia strains (100% have produced ammonia, whereas 80% of Bacillus and 77.77% of Pseudomonas produced this metabolite. The hydrogen cyanide was produced by all isolates (100% independent of their genus. These results suggest the possibility to use these rhizobacteria as biological fertilizers to increase maize production.

  3. Psychometric properties of teacher-made science tests used in national examinations for middle-grade students in Benin (West Africa): A longitudinal study

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    Gado, Issaou

    The purpose of this study was to determine the psychometric properties (item difficulty, item discrimination, internal consistency reliability, content validity and construct validity) of teacher-made science tests used in national examinations for Middle Grade students in Benin (West Africa) for three consecutive years. The study also described the assessment methods used in science classrooms. Research data were collected from two sources: first, a survey questionnaire administered to 250 secondary school teachers purposively selected; second, a total of 630 graded physical science copies for three consecutive years of national examinations randomly selected from the Service of Examination and Testing data sources. Descriptive statistics were used to analyze the survey questionnaire. Factor analysis was used to explore construct validity of the measurements. Classical test theory methods were used to explore item difficulty, item discrimination, and reliability of examination scores. Generalizability theory provided estimate of variance components and proportions of total variance accounted for by sources of error related to persons, items, and person-by-item interaction. The result of this study shows that teacher-made tests used in large scale high-stakes examination for three consecutive years are highly reliable and have a satisfactory level of difficulty and discrimination. However, even though the items of teacher-made tests are associated with the objectives of the national curriculum standards, the proportion of objectives tested in national examinations and the number of items across three consecutive years show a non uniform and inconsistent distribution of items across years, content domains, and within the fields of chemistry and physics. Therefore, teacher-made tests used in national examinations for three consecutive years lack content validity. Discussion of the results and suggestions about constructing exam items with high validity are provided.

  4. Some particularities of rainfall variability in a transition climate: case of the Department of the ZOU in Benin - West Africa

    International Nuclear Information System (INIS)

    The field of study is located in the middle Benin. It corresponds to the field of transition between the subequatorial climate to the south and the Soudan ian climate in the north. The basic conviction is that to measure the climatic changes, which occur, it is necessary to look at the changes in the zones of margin. We thus examined some of meteorological events such as pluviometric regime, the monthly concentration of the rains, the beginning and end of the rainy season, events which contrast with those of the framing facies climatic, which enabled us to know in which direction the changes take place. The following reports were made: There is a greater concentration of the rains over the wet months (June, July, August and September) The inflection of the rains of August tends to disappear so that this month. It is wet This way, the bimodal style tends to disappear in favor of the unimodal, which confirms the CV (coefficient of variation) of which the low value shows a certain stability. The volume of the rains in beginning as at the end of the wet period decreased almost everywhere in the band. In fact there reports make think of the Soudanian climate and one can wonder whether the Soudanian does not tend to, impose its rate/rhythm on this latitude. Anyway the assumption of a climatic change rate tends to prove correct. One can wonder how long this tendency will last.(Author)

  5. Lions of West Africa: ecology of lion (Panthera leo Linnaeus 1975) populations and human-lion conflicts in Pendjari Biosphere Reserve, North Benin

    OpenAIRE

    Sogbohossou, Etotépé Aïkpémi

    2011-01-01

    The Earth’s biodiversity is disappearing at an alarming rate in the last decades. Many species, including carnivores, are becoming endangered. The lion was one of the most widely distributed terrestrial mammals and is today restricted to Gir ecosystem in India and to more or less fragmented populations in sub-saharan Africa. The species is considered as Vulnerable on IUCN Red List. In West Africa, due to its small and fragmented populations, the species is listed as Regionally Endangered. Whi...

  6. Statistical postprocessing of precipitation generated with the mesoscale model FOOT3DK for the rainy season 2002 in Benin (West Africa)

    Science.gov (United States)

    Ludwig, P.; Krüger, A.; Born, K.; Kerschgens, M.

    2009-04-01

    The presented study deals with various aspects of mesoscale modelling of precipitation in the Sudanian Region at the West African subcontinent and is imbedded into an interdisciplinary research project called IMPETUS. Environmental conditions of synoptic-scale features, being responsible regarding generation and propagation of several precipitation systems, are mostly influenced by the West African Monsoon system. For investigations of precipitation events during the rainy season of 2002, a total number of 40 precipitation episodes, with durations ranging from 54 to 72 hours for each episode, were simulated using the non-hydrostatic model FOOT3DK. While the spatial resolution is 3 km, the temporal resolution accounts for 1 hour. Input data for these simulations is provided using a model chain consisting GME-analysis, Lokal-Modell (0.25° resolution) and FOOT3DK (9 km resolution). The investigated area covers a region of 105 km x 105 km (35 x 35 grid points) and is situated in the upper river catchment of the Ouémé in Benin. On basis of a total number of 50 rainfall recording stations comparisons between simulated and observed precipitation within this study has been carried out. The recording stations are irregularly spaced across the investigated area. The accomplished comparison of precipitation adverts to the necessity for an adjustment of simulated rainfall by FOOT3DK. Therefore, an adjustment technique has been developed and is presented within this study. Based on the 1225 grid points this method fits the hourly simulated towards the hourly observed rainfall rates using a mapping function. In a first step the station data has to be interpolated to the same underlying model grid. Afterwards, the desired relation between simulated and observed precipitation can be established by fitting a sigmoidal curve to the precipitation data using the Levenberg-Marquardt-Algorithm. For every single grid mesh a separate Gompertz function can be found and employed. The

  7. FACTORS ASSOCIATED WITH THE UPTAKE OF SODIUM DICHLOROISOCYANURATE (NADCC) TABLETS AS HOUSEHOLD WATER-TREATMENT PRODUCT AMONG CAREGIVERS OF CHILDREN UNDER FIVE IN BENIN, WEST AFRICA.

    Science.gov (United States)

    Inungu, Joseph N; Zinsou, Cyprien E; Mustafa, Younis; Singbo, Narcisse

    2016-01-01

    Improving access to safe drinking water is a critical step in mitigating diarrheal diseases that affect millions of children under 5 years throughout the developing world each year. While the delivery of safe water is out of the reach of many countries, the utilization of Sodium dichloroisocyanurate (NaDCC) is a proven cost-effective alternative to prevent diarrhea caused by waterborne pathogens. However, its uptake remains low in many developing countries, such as the Republic of Benin. This study examines the trends and the determinants of NaDCC uptake in Benin. Population Services International and its affiliate conducted two multistage household surveys among caregivers of children under five in Benin to examine the practices towards diarrheal disease in children under five and identify the factors associated with the use of NaDCC in this population. 2912 respondents/caregivers of children under five were interviewed in 2009 versus 3196 in 2011. The proportion of caregivers who reported ever treating water with NaDCC increased from 5.8% in 2009 to 11.5% in 2011, p product. In order to increase the use of NADCC among caregivers, the Government of Benin and its development partners should focus not only on making NADCC available in the community and informing the community members about the different points of sale, but also in building up the capacity and confidence of caregivers in utilizing it. PMID:27483977

  8. Managing the agricultural calendar as coping mechanism to climate variability: A case study of maize farming in northern Benin, West Africa

    OpenAIRE

    Rosaine N. Yegbemey; Humayun Kabir; Oyémonbadé H.R. Awoye; Yabi, Jacob A.; Armand A. Paraïso

    2014-01-01

    Nowadays climate variability and change are amongst the most important threats to sustainable development, with potentially severe consequences on agriculture in developing countries. Among many available coping mechanisms, farmers adjust some of their farming practices. This article aims at exploring observed changes in the agricultural calendar as a response to climate variability in northern Benin. Interviews with local experts (agricultural extension officers and local leaders such as hea...

  9. Managing the agricultural calendar as coping mechanism to climate variability: A case study of maize farming in northern Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Rosaine N. Yegbemey

    2014-01-01

    Full Text Available Nowadays climate variability and change are amongst the most important threats to sustainable development, with potentially severe consequences on agriculture in developing countries. Among many available coping mechanisms, farmers adjust some of their farming practices. This article aims at exploring observed changes in the agricultural calendar as a response to climate variability in northern Benin. Interviews with local experts (agricultural extension officers and local leaders such as heads of farmer and village organisations and group discussions with farmers were organised. A household survey was also conducted on 336 maize producers to highlight the factors affecting decisions to adjust the agricultural calendar as a coping mechanism against climate variability. As a general trend, the duration of the cropping season in northern Benin is getting longer with slight differences among and within agro-ecological zones, implying a higher risk of operating under time-inefficient conditions. Farmers receive very limited support from agricultural extension services and therefore design their agricultural calendar on the basis of personal experience. Socio-economic characteristics, maize farming characteristics as well as farm location determine the decision to adjust the agricultural calendar. Consequently, providing farmers with climate related information could ensure a rational and time-efficient management of the agricultural calendar. Moreover, research and extension institutions should help in establishing and popularising clear agricultural calendars while taking into account the driving forces of behaviours towards the adjustment of farming practices as a climate variability response.

  10. Response of the Bight of Benin (Gulf of Guinea, West Africa) coastline to anthropogenic and natural forcing, Part1: Wave climate variability and impacts on the longshore sediment transport

    Science.gov (United States)

    Almar, R.; Kestenare, E.; Reyns, J.; Jouanno, J.; Anthony, E. J.; Laibi, R.; Hemer, M.; Du Penhoat, Y.; Ranasinghe, R.

    2015-11-01

    The short, medium and long-term evolution of the sandy coastline of the Bight of Benin in the Gulf of Guinea, West Africa, has become a major regional focal point due to the rapid socio-economic development that is occurring in the region, including rapid urbanization and a sharp increase in harbor-based trade. Harbors have a significant impact on the present evolution of this coast, notably by affecting longshore sediment transport. However, little is known of the environmental drivers, notably the wave climate, that governs longshore sediment transport and the ensuing pattern of shoreline evolution of this coastal zone. This article aims to address this important knowledge gap by providing a general overview of coastal evolution in the Bight of Benin and the physical processes that control this evolution. Here, the 1979-2012 ERA-Interim hindcast is used to understand the temporal dynamics of longshore sediment transport. Oblique waves (annual average Hs=1.36 m, Tp=9.6 s, S-SW incidence) drive an eastward drift of approximately 500,000 m3/yr. The waves driving this large longshore transport can be separated into two components with distinct origins and behavior: wind waves generated locally in the Gulf of Guinea and swell waves generated in the southern hemisphere sub- (30-35°S), and extra-tropics (45-60°S). The analysis undertaken here shows that the contribution to the gross annual longshore transport from swell wave-driven longshore currents is an order of magnitude larger than the local wind wave-driven longshore currents. Swell waves are dominantly generated by westerlies in the 40-60°S zone and to a lesser extent by trade winds at 30-35°S. The longshore sediment drift decay (-5% over 1979-2012) is found to be linked with a decrease in the intensity of westerly winds associated with their southward shift, in addition to a strengthening of the trade winds, which reduces the eastward sediment transport potential. The equatorial fluctuation of the Inter

  11. C4 plant isotopic composition (delta13C) evidence for urban CO2 pollution in the city of Cotonou, Benin (West Africa).

    Science.gov (United States)

    Kèlomé, Nelly C; Lévêque, Jean; Andreux, Francis; Milloux, Marie-Jeanne; Oyédé, Lucien-Marc

    2006-08-01

    The carbon isotopic composition (delta13C) of plants can reveal the isotopic carbon content of the atmosphere in which they develop. The delta13C values of air and plants depend on the amount of atmospheric fossil fuel CO2, which is chiefly emitted in urban areas. A new indicator of CO2 pollution is tested using the delta13C variation in a C4 grass: Eleusine indica. A range of about 4 per thousand delta units was observed at different sites in Cotonou, the largest city in the Republic of Benin. The highest delta13C values, from -12 per thousand to -14 per thousand, were found in low traffic zones; low delta13C values, from -14 per thousand to -16 per thousand, were found in high traffic zones. The amount of fossil fuel carbon assimilated by plants represented about 20% of the total plant carbon content. An overall decrease in plant delta13C values was observed over a four-year monitoring period. This decrease was correlated with increasing vehicle traffic. The delta13C dataset and the corresponding geographical database were used to map and define zones of high and low 13C-depleted CO2 emissions in urban and sub-urban areas. The spatial distribution follows dominant wind directions, with the lowest emission zones found in the southwest of Cotonou. High CO2 emissions occurred in the north, the east and the center, providing evidence of intense anthropogenic activity related to industry and transportation.

  12. Benin.

    Science.gov (United States)

    1984-11-01

    Focus in this discussion of Benin is on the following: the people; geography; history; government and political conditions; economy; defense; foreign relations; and relations between the US and Benin. The population totaled 3.8 million in 1983 with an annual growth rate of 2.6%. The infant mortality rate is 45/1000 and life expectancy 46.9 years. The population comprises about 20 sociocultural groups. 4 groups -- the Fon, Aja, Bariba, and Yoruba -- account for more than half of the population. The name was changed from Dahomey to the People's Republic of Benin in 1975. 2 years after the military coup d'etat in 1972, Marxism-Leninism was declared the guiding philosophy of the new government. Marxism-Leninism remains the official doctrine, but the government has moved to take account of popular resistance to a radical social transformation, as well as problems encountered in attempting to establish a centrally directed economy. Benin is ranked as 1 of the world's 35 poorest countries. The commercial, industrial, and agricultural sectors are all experiencing severe problems. The government's newest 5 year plan for 1983-88 places a stronger emphasis on developing agriculture. In so doing, the government hopes to assure its own domestic needs and to become a supplier of basic foodstuffs to the region. Benin's Armed Forces number about 3000 personnel. Benin is a member of the Non-Aligned Movement and the Organization of African Unity. Relations with France are important because of historical, cultural, economic, and aid links. After 1972, relations between the US and Benin became strained as Benin moved to strengthen its ties with the Soviet Union and other socialist countries and mounted harsh propaganda attacks on the US. PMID:12178102

  13. Predictions of sea-level rise for coastal geosystem of Togo (between Volta and Mono Rivers in the Gulf of Benin/West Africa); Physical and economic manifestations

    International Nuclear Information System (INIS)

    The coastal zone of Togo is very narrow and covers an area of 1,710 square kilometers. It constitutes an essential economic potential of the country due to the concentration of more than 90% of its economic activities, more than 42% of its whole population and of that of Lome. The coastal landscape encompasses the delta system of the Volta river in Ghana to which are adjoined the clearly differentiated offshore bars, parallel to the coast and the uninterrupted lagoon systems which run into the alluvial plain of the Mono River. The coastline is located in the current offshore bar at a mean of 2 and 3 meters above average sea level. It is lower, at 1 meter in the barrier crossbar at the level of the lagoon and river mouths. The climatic regime of the coastal zone depends upon two air currents with two contrasted seasons during the year. The temperatures are constant throughout the year and vary between 25 deg. and 28 deg. C. The coastal geosystem is fed by the Volta and Mono Rivers. The dams built on the two rivers put a limit on the sedimentary volume drift to the sea: this accentuates the sedimentary loss and erosion in the lagoon zone and around the mouths of the rivers. The hydrodynamic regime is conditioned by local and regional meteorological elements, namely the marine winds of the Southern Ocean which generate swells and waves. These waves create on the coast a current of coastal drifting west to east, which activates the mechanism of the coastal morphosedimentary process. An examination of the sandy coasts where a current withdrawal of the seashore is noticed in West and Central Africa shows that this dynamic process is generally the result of human action. It is not linked to the sea transgression correlative to the greenhouse effect. Scientific research as regards climate confirms the greenhouse effect linked to the increase of the CO2 content in the atmosphere which could probably be the cause of climatic change with subsequent rise in temperature from 1

  14. Dracaena in West Africa

    NARCIS (Netherlands)

    Bos, J.J.

    1984-01-01

    This taxonomic revision of the genus Dracaena L. (Liliaceae) in West Africa is another contribution towards a monograph on this group.Short general chapters contain historical, phytogeographical, morphological and phylogenetic observations. The taxonomic treatment contains a revised genus descriptio

  15. Benin.

    Science.gov (United States)

    1989-03-01

    In 1988, Benin had a population of 4 million and an annual growth rate of 3.6%. Life expectancy was 49 years, and infant mortality stood at 116/1000 live births. Primary school enrollment is about 65%, with 6 years of compulsory education, and the adult literacy rate is only 11%. Of the labor force of 1.9 million, 72% are engaged in agriculture. Benin's gross domestic product was US$1497 million in 1987, with an annual growth rate of 7.1% and a per capita income of $374. Despite the Marxist-Leninist ideology of the Kerekou Government, many government-controlled sectors of the economy are being privatized and private foreign firms have been authorized to operate in Benin's transport sector. These changes have been necessitated by heavy losses suffered by nationalized industries and the worsening economic situation. Benin's economy, heavily dependent on regional trade and the export of cotton and crude oil, has been severely affected by ineffective government policies, regional recession, the collapse of world commodity prices, heavy external debt, balance of payment deficits, and very low foreign exchange reserves and liguidity. The 5-Year Plan (1983-88) emphasized the development of agriculture and the goal of becoming a supplier of basic foodstuffs to the region. PMID:12177990

  16. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Howard Annabel FV

    2010-09-01

    Full Text Available Abstract Background Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show that entomopathogenic fungi can kill insecticide-resistant malaria vectors but this needs to be verified in the field. Methods The present study investigated whether these fungi will be effective at infecting, killing and/or modifying the behaviour of wild multi-insecticide-resistant West African mosquitoes. The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were separately applied to white polyester window netting and used in combination with either a permethrin-treated or untreated bednet in an experimental hut trial. Untreated nets were used because we wanted to test the effect of fungus alone and in combination with an insecticide to examine any potential additive or synergistic effects. Results In total, 1125 female mosquitoes were collected during the hut trial, mainly Culex quinquefasciatus Say. Unfortunately, not enough wild Anopheles gambiae Giles were collected to allow the effect the fungi may have on this malaria vector to be analysed. None of the treatment combinations caused significantly increased mortality of Cx. quinquefasciatus when compared to the control hut. The only significant behaviour modification found was a reduction in blood feeding by Cx. quinquefasciatus, caused by the permethrin and B. bassiana treatments, although no additive effect was seen in the B. bassiana and permethrin combination treatment. Beauveria bassiana did not repel blood foraging mosquitoes either in the laboratory or field. Conclusions This is the first time that an entomopathogenic fungus has been shown to reduce blood feeding of wild mosquitoes. This behaviour modification indicates that B. bassiana could potentially be a new

  17. Vegetation patterns and environmental gradients in Benin

    NARCIS (Netherlands)

    Adomou, A.

    2005-01-01

    Key words: West Africa, Benin, vegetation patterns, floristic areas, phytogeography, chorology, floristic gradients, climatic factors, water availability, Dahomey Gap, threatened plants, biodiversity, conservation.Understanding plant species distribution patterns and the underlying factors is a cruc

  18. Drought in West Africa

    Science.gov (United States)

    2007-01-01

    Drought settled over West Africa's Ivory Coast region when wet season rains came late in 2007. Instead of beginning in February, the rainy season didn't start until March, and steady rains didn't start until late March, said the Famine Early Warning System Network. Though the rain had started to alleviate the drought, vegetation was still depressed in parts of Cote d'Ivoire (Ivory Coast) between March 22 and April 6, 2007, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite captured the data used to make this image. The image shows current vegetation conditions compared to average conditions recorded since 2000. Areas where plants are growing more slowly or more sparsely than average are brown, while areas where vegetation is denser than average are green. The brown tint that dominates the image indicates that plants through most of the country are more sparse than normal. Among the crops affected by the lack of rain was West Africa's cocoa crop. About 70 percent of the world's cocoa comes from West Africa, and Cote d'Ivoire is a top grower, said Reuters. Cocoa prices climbed as the crop fell short. Farmers called the drought the worst in living memory, Reuters said. The delay in rainfall also led to water shortages in parts of Cote d'Ivoire, according to the United Nations Office for the Coordination of Humanitarian Affairs.

  19. Trade networks in West Africa

    DEFF Research Database (Denmark)

    Walther, Olivier

    2014-01-01

    To date, most of the literature on trade networks in West Africa has considered networks in a metaphorical way. The aim of this paper is to go one step further by showing how social network analysis may be applied to the study of regional trade in West Africa. After a brief review of the literature...... at the influence of spatial location and geographic scale on traders’ abilities to trade. In both cases, we argue that the value of social network analysis in exploring how traders have progressively adapted to social and spatial changes in economic activities has been greatly underestimated. Our discussion...

  20. Unravelling institutional determinants affecting change in agriculture in West Africa

    NARCIS (Netherlands)

    Struik, P.C.; Klerkx, L.W.A.; Hounkonnou, D.

    2014-01-01

    This paper compares lessons learned from nine studies that explored institutional determinants of innovation towards sustainable intensification of West African agriculture. The studies investigated issues relating to crop, animal, and resources management in Benin, Ghana, and Mali. The constraints

  1. The electrical power market in West and East Africa

    International Nuclear Information System (INIS)

    The growing energy demand in Africa has promoted countries such as Benin, Cote d'Ivoire, Ghana, Nigeria, Senegal, Kenya and Tanzania to use the services of independent power producers (IPP) to add power generating capacity to meet the growing power needs. Several countries in Africa are also promoting market competition, foreign investment and co-operation between countries. Ghana and Uganda are working on developing the hydroelectric potential in the country. One of the priorities for the national governments in Africa is to expand the power supply infrastructure. Kenya, Uganda, Tanzania and other West African countries are consolidating their electricity systems to integrate and interconnect their power transmission lines. In an effort to stimulate economic growth, there has been a concerted effort to shift from expensive hydro-electric power projects to natural gas projects including infrastructure developments such as the West African Natural Gas Pipeline that will provide opportunities for Canadian investment. In addition, Canadian companies could supply equipment and services to the renewable energy sector, particularly medium-scale hydro projects. Other opportunities lie in supply equipment, new generation-capacity projects, infrastructure in terms of power transmission and distribution, and rural electrification programs. Foreign partners are also being sought for consultation and engineering services to set up national power grids and to improve the efficiency of the existing power grid system. It was noted that joint-ventures are preferred for the transfer technologies or for setting up local manufacturing presence by foreign investment. refs

  2. Addressing diarrhea prevalence in the West African Middle Belt: social and geographic dimensions in a case study for Benin

    Directory of Open Access Journals (Sweden)

    Arouna Aminou

    2008-04-01

    Full Text Available Abstract Background In West Africa, the Northern Sahelian zone and the coastal areas are densely populated but the Middle Belt in between is in general sparsely settled. Predictions of climate change foresee more frequent drought in the north and more frequent flooding in the coastal areas, while conditions in the Middle Belt will remain moderate. Consequently, the Middle Belt might become a major area for immigration but there may be constraining factors as well, particularly with respect to water availability. As a case study, the paper looks into the capacity of the Middle Belt zone of Benin, known as the Oueme River Basin (ORB, to reduce diarrhea prevalence. In Benin it links to the Millennium Development Goals on child mortality and environmental sustainability that are currently farthest from realization. However, diarrhea prevalence is only in part due to lack of availability of drinking water from a safe source. Social factors such as hygienic practices and poor sanitation are also at play. Furthermore, we consider these factors to possess the properties of a local public good that suffers from under provision and requires collective action, as individual actions to prevent illness are bound to fail as long as others free ride. Methods Combining data from the Demographic Health Survey with various spatial data sets for Benin, we apply mixed effect logit regression to arrive at a spatially explicit assessment of geographical and social determinants of diarrhea prevalence. Starting from an analysis of these factors separately at national level, we identify relevant proxies at household level, estimate a function with geo-referenced independent variables and apply it to evaluate the costs and impacts of improving access to good water in the basin. Results First, the study confirms the well established stylized fact on the causes of diarrhea that a household with access to clean water and with good hygienic practices will, irrespective of

  3. Regionalizing Telecommunications Reform in West Africa

    OpenAIRE

    World Bank

    2007-01-01

    This report assesses the potential gains from regionalized telecommunications policy in West Africa. The report seeks to assist officials in the Economic Community of West African States (ECOWAS), the West African Telecommunications Regulators Assembly (WATRA) and member states in designing an effective regional regulatory process. To this end, the report: (i) discusses how regional coop...

  4. DPA1*02012: A DPA1*0201-related Mhc class II allele in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, C.G.; May, J.; Spauke, D.; Schnittger, L. [Bernhard Nocht Institute for Tropical Medicine, Hamburg (Germany)

    1994-12-31

    DNA techniques such as sequence-specific oligonucleotide probe (SSOP) hybridizations, restriction-fragment length polymorphism (RFLP) analyses, and DNA sequencing have greatly supported the characterization of Mhc class II allelic polymorphism. Here the authors describe a DPA 1 allele which has been identified in two male individuals from Liberia and Benin, West Africa, during a survey study on Mhc class II associations with the different manifestations after infection with Onchocerca volvulus. 4 refs., 1 fig.

  5. Political ecology in the oil palm-based cropping system on the Adja plateau in Benin: connecting soil fertility and land tenure

    NARCIS (Netherlands)

    Yemadje, H.R.M.

    2013-01-01

    Keywords: Innovation system, Soil fertility management, Land reform, Participatory technology development, Social change, Agroforestry, Land access rights, Fallow, Agricultural intensification, Africa   On the Adja plateau (West Benin), multiple actors are involved in an intercropping system

  6. Namibia [South-West Africa].

    Science.gov (United States)

    1983-01-01

    Namibia, a country of 1,051,700 inhabitants of whom 85.6% are blacks of diverse ethnic and linguistic origins, 7.5% are white, and the rest are of mixed ancestry, has been illegally administered by South Africa since 1966, when a League of Nations mandate was revoked by the UN. The Namibian Desert was a barrier to European expansion until the late 18th century, when the area came under German and British influence. Efforts to bring about an orderly and peaceful transition to independent status are hampered at present by the lack of parallel progress toward withdrawal of Cuban combat forces from Angola. Beginning in 1980, considerable executive power was transferred from the administrator general appointed by the South African Government to an interim 3-tier system of elected representatives dividing responsibility between central, ethnic, and local authorities. The judicial structure has separate overlapping systems for whites, westernized blacks and coloreds and for indigenous blacks. Namibian society is highly politicized, with 4 white and about 40 nonwhite political groups. The South West Africa People's Organization (SWAPO) remains an active party inside Namibia despite simultaneous detention of its entire leadership in 1979 by the South African Government. Namibia's economy is dual, with a modern market sector of mining, ranching and fishing producing most of the wealth and a traditional subsistence sector supporting most of the labor force. About 60% of the work force of 500,000 in 1981 worked in agriculture, 19% in industry and commerce, 6% in mining, 8% in services, and 7% in government. Namibia's gross domestic product in 1980 was $1.712 billion, representing an average growth rate of 2.5% from 1970-80. However, real growth since 1978 has been negative because of persistent drought, political uncertainty, low demand for mineral products, and previous overfishing. Namibia has no separate representation in any international body. The country may have the

  7. Legume Diversity Patterns in West Central Africa

    NARCIS (Netherlands)

    Estrella, de la M.; Mateo, M.A.; Wieringa, J.J.; Mackinder, B.; Munoz, J.

    2012-01-01

    Objectives - Species Distribution Models (SDMs) are used to produce predictions of potential Leguminosae diversity in West Central Africa. Those predictions are evaluated subsequently using expert opinion. The established methodology of combining all SDMs is refined to assess species diversity withi

  8. Secondary Organic Aerosol from biogenic VOCs over West Africa during AMMA

    Directory of Open Access Journals (Sweden)

    G. Capes

    2009-01-01

    Full Text Available This paper presents measurements of organic aerosols above subtropical West Africa during the wet season using data from the UK Facility for Airborne Atmospheric Measurements (FAAM aircraft. Measurements of biogenic volatile organic compounds (BVOC at low altitudes over these subtropical forests were made during the African Monsoon Multidisciplinary Analysis (AMMA field experiment during July and August 2006 mainly above Benin, Nigeria and Niger. Data from an Aerodyne Quadrupole Aerosol Mass Spectrometer show a median organic aerosol loading of 1.08 μg m−3 over tropical West Africa, which represents the first regionally averaged assessment of organic aerosol mass (OM in this region during the wet season. This is in good agreement with predictions based on aerosol yields from isoprene and monoterpenes during chamber studies and model predictions based on partitioning schemes, contrasting markedly with the large under representations of OM in similar models when compared with data from mid latitudes.

  9. Land use scenarios development and impacts assessment on vegetation carbon/nitrogen sequestration in the West African Sudan savanna watershed, Benin

    Science.gov (United States)

    Chabi, A.

    2015-12-01

    ackground: Reduced Emissions from Deforestation and Degradation (REDD+), being developed through the United Nations Framework Convention on Climate Change (UNFCCC) requires information on the carbon/nitrogen stocks in the plant biomass for predicting future climate under scenarios development. The development of land use scenarios in West Africa is needed to predict future impacts of change in the environment and the socio-economic status of rural communities. The study aims at developing land use scenario based on mitigation strategy to climate change as an issue of contributing for carbon and nitrogen sequestration, the condition 'food focused' as a scenario based crop production and 'financial investment' as scenario based on an economic development pathway, and to explore the possible future temporal and spatial impacts on vegetation carbon/nitrogen sequestration/emission and socio-economic status of rural communities. Preliminary results: BEN-LUDAS (Benin-Land Use DyNamic Simulator) model, carbon and nitrogen equations, remote sensing and socio-economic data were used to predict the future impacts of each scenario in the environment and human systems. The preliminary results which are under analysis will be presented soon. Conclusion: The proposed BEN-LUDAS models will help to contribute to policy decision making at the local and regional scale and to predict future impacts of change in the environment and socio-economic status of the rural communities. Keywords: Land use scenarios development, BEN-LUDAS, socio-economic status of rural communities, future impacts of change, assessment, West African Sudan savanna watershed, Benin

  10. Agricultural innovation in Africa : from soil fertility to market integration. A case study from Benin

    OpenAIRE

    Jeannin, Marianne

    2013-01-01

    In Benin, in response to the declining soil fertility and its effects on food insecurity and natural resources, farmers supported by external agents such as researchers, extension services and NGOs have developed new soil fertility management practices. In this study, we trace the history of the development of Integrated Soil Fertility Management (ISFM) initiatives in three different agro-ecological zones of Benin and highlight the different development phases and outcomes...

  11. Community wildlife management in west africa : a regional overview

    OpenAIRE

    Zeba, S.

    1998-01-01

    This report is intended to be a West African contribution to a global study of IIED on community wildlife management issues. Its geographic focus is the 16 member countries of the Economic Community Of West African States (ECOWAS), including 9 francophone countries (Benin, Burkina Faso, Niger, Mali, Ivory-Coast, Mauritania, Senegal, Guinea,Togo), 5 anglophone countries (Ghana, Liberia, Nigeria, Sierra Leone, The Gambia) and 2 lusophone countries (Guinea Bissau, Cape Verde). This region has mo...

  12. Mastomys natalensis and Lassa Fever, West Africa

    OpenAIRE

    Lecompte, Emilie; Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kan, Stéphane Kouassi; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane

    2006-01-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans.

  13. Mastomys natalensis and Lassa fever, West Africa.

    Science.gov (United States)

    Lecompte, Emilie; Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kouassi Kan, Stéphane; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane; ter Meulen, Jan

    2006-12-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans. PMID:17326956

  14. Mastomys natalensis and Lassa Fever, West Africa

    Science.gov (United States)

    Fichet-Calvet, Elisabeth; Daffis, Stéphane; Koulémou, Kékoura; Sylla, Oumar; Kourouma, Fodé; Doré, Amadou; Soropogui, Barré; Aniskin, Vladimir; Allali, Bernard; Kan, Stéphane Kouassi; Lalis, Aude; Koivogui, Lamine; Günther, Stephan; Denys, Christiane; ter Meulen, Jan

    2006-01-01

    PCR screening of 1,482 murid rodents from 13 genera caught in 18 different localities of Guinea, West Africa, showed Lassa virus infection only in molecularly typed Mastomys natalensis. Distribution of this rodent and relative abundance compared with M. erythroleucus correlates geographically with Lassa virus seroprevalence in humans. PMID:17326956

  15. Transcending Communication Barriers with West Africa.

    Science.gov (United States)

    Ampadu, Lena

    Americans doing business with West Africans are limited in their ability to communicate successfully in that part of the world because of language, stereotyping, and ethnocentrism. Americans must become accustomed to British patterns of speech and writing. Stereotypes of Africa, its people, and its cultures perpetuated by the media keep Americans…

  16. Teaching Scandinavian Interaction Design in West Africa

    DEFF Research Database (Denmark)

    Sørensen, Jannick Kirk

    2016-01-01

    Methods for interaction design have emerged and established themselves first in a Scandinavian context, later in US context and in the rest of the developed world. While good usability and good user experiences are important to all users of ICT, the question is whether the methods and techniques ...... Scandinavian Participatory design can be used to localize the learning process and make interaction design methods sensitive to the West African context. The paper is based on the author’s reflection on his experiences teaching interaction design in West Africa....

  17. Usability and Interaction Design in West Africa

    DEFF Research Database (Denmark)

    Sørensen, Jannick Kirk

    Good usability is important in all ICT solutions. To achieve good usability, a good praxis for interaction design is needed. Usability and interaction design have however emerged and established itself in a North European and US context. The ICT industry in Africa do not have the same resources...... in the field of interaction design as in the developed world. While good usability and good user experiences are important to all users of ICT, the question is whether the methods and techniques that were mainly developed in Scandinavia, Europe and US are suitable for ICT development in Africa? Can ideals...... for user-involvement and participatory design be directly transferred? How can interaction design and usability be cared for in African ICT development context, given the resources available? This paper aims to initiate a discussion of the conditions for interaction design and usability in West Africa...

  18. The current capacity for training in public health nutrition in West Africa.

    Science.gov (United States)

    Pepping, Fré

    2010-01-01

    This article is based on a paper prepared for the Workshop on Establishing a Regional Institute for Public Health Nutrition Research and Training in West Africa, convened in Dakar, Senegal, 26-28 March, 2009. Information was gathered mainly prior to this workshop; several responses, however, came in after the workshop and these have been included in the current paper. In completion of the article use was made of the views and opinions as expressed during this workshop. Objectives were to provide background information on academic programmes (undergraduate and graduate) and research institutions with a focus on human nutrition in West Africa, to describe the importance of foreign nutrition training programmes for West African students and to detail existing nutrition training activities currently in the region. Data were obtained from a survey of 15 UNICEF country offices in the West African region, previously published reports, United Nations University/International Union of Nutrition Sciences capacity development activities 1996-2009, personal communications and websites of relevant African institutions. Results indicate that West African nutrition academic programmes and research institutes do not adequately meet the demand for nutritionists and technical services in the region. Exceptions seem to be Benin, Ghana and Nigeria. Diploma courses and other short courses have been an important means of attracting people from a variety of disciplines to nutrition. A well-equipped regional institute could directly and indirectly bolster nutrition capacity in the region. To meet the regional nutrition research and training needs in West Africa, it is not necessary to make a choice between creating a new regional institution vs. expanding existing national institutions. Based on solid capacity development principles, both options need action. PMID:21113829

  19. Regional trade and border markets between Niger, Benin and Nigeria: A methodological note

    DEFF Research Database (Denmark)

    Walther, Olivier; Tenikué, Michel; Kuepié, Mathias

    The objective of this methodological paper is to identify a number of products or sectors whose trade is relevant for border regions in West Africa. Focusing on Niger, Benin and Nigeria, we start with contextualising the importance of border markets by quantifying the changes in the relative values...

  20. Networking, social capital and gender roles in the cotton system in Benin

    NARCIS (Netherlands)

    Maboudou Alidou, G.

    2014-01-01

    Cotton production in Benin, West Africa, is intertwined with colonialism, which contributed to the trans­formation of the crop’s production system from traditional to modern. Through­out the years, the importance of the crop for the stakeholders varied. The last decades have witnessed

  1. Regional trade and economic networks in West Africa

    OpenAIRE

    Walther, Olivier

    2012-01-01

    To date, most of the literature on economic networks in West Africa has considered networks in a metaphorical way. The aim of this paper is to go one step further by showing how network analysis may be applied to the study of regional trade in West Africa. After a brief review of the literature, this exploratory paper investigates two main issues related to regional trade. We start by discussing how recent developments in regional trade in West Africa, brought on by urbanization, liberalizati...

  2. New emerging West Africa Ebola 2014:the present global threaten

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwanitkit

    2014-01-01

    New emerging West Africa Ebola 2014 is the present global threaten. It is a new emerging viral infection that primarily occurred in West Africa and poses the possible trend of worldwide pandemic. The 2014 West Africa Ebola outbreak is the most severe in recorded history in regards to both the number of human cases and fatalities. World Health Organization calls for global concern and attempts to stop the spread of this emerging viral infection. In this brief review, the author presents and discusses on the clinical feature of the new emerging West Africa Ebola 2014.

  3. New emerging West Africa Ebola 2014: the present global threaten

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2014-07-01

    Full Text Available New emerging West Africa Ebola 2014 is the present global threaten. It is a new emerging viral infection that primarily occurred in West Africa and poses the possible trend of worldwide pandemic. The 2014 West Africa Ebola outbreak is the most severe in recorded history in regards to both the number of human cases and fatalities. World Health Organization calls for global concern and attempts to stop the spread of this emerging viral infection. In this brief review, the author presents and discusses on the clinical feature of the new emerging West Africa Ebola 2014.

  4. Niobium content of soils from West Africa

    Science.gov (United States)

    Grimaldi, F.S.; Berger, I.A.

    1961-01-01

    Analysis of twenty lateritic soil samples from West Africa has shown them to contain an average 24 p.p.m. of niobium; four similar samples taken from within a few miles from a niobium deposit contain from 79 to 87 p.p.m. niobium. It has been shown that as the aluminum content of the soils increases, the following depletion sequence is obtained: Si > Nb > Al = Fe The data indicate that, in general, high enrichments of niobium are not to be expected in lateritic soils. ?? 1961.

  5. Land Conflict, Migration, and Citizenship in West Africa

    OpenAIRE

    Maze, Kerry

    2015-01-01

    Land and property rights, migration, and citizenship are complex issues that cut across all social, economic, and political spheres of West Africa. This paper provides an overarching scoping of the most pressing contemporary issues related to land, migration, and citizenship, including how they intersect in various contexts and locations in West Africa. The way issues are analytically fram...

  6. Risk maps of Lassa fever in West Africa.

    Directory of Open Access Journals (Sweden)

    Elisabeth Fichet-Calvet

    Full Text Available BACKGROUND: Lassa fever is caused by a viral haemorrhagic arenavirus that affects two to three million people in West Africa, causing a mortality of between 5,000 and 10,000 each year. The natural reservoir of Lassa virus is the multi-mammate rat Mastomys natalensis, which lives in houses and surrounding fields. With the aim of gaining more information to control this disease, we here carry out a spatial analysis of Lassa fever data from human cases and infected rodent hosts covering the period 1965-2007. Information on contemporary environmental conditions (temperature, rainfall, vegetation was derived from NASA Terra MODIS satellite sensor data and other sources and for elevation from the GTOPO30 surface for the region from Senegal to the Congo. All multi-temporal data were analysed using temporal Fourier techniques to generate images of means, amplitudes and phases which were used as the predictor variables in the models. In addition, meteorological rainfall data collected between 1951 and 1989 were used to generate a synoptic rainfall surface for the same region. METHODOLOGY/PRINCIPAL FINDINGS: Three different analyses (models are presented, one superimposing Lassa fever outbreaks on the mean rainfall surface (Model 1 and the other two using non-linear discriminant analytical techniques. Model 2 selected variables in a step-wise inclusive fashion, and Model 3 used an information-theoretic approach in which many different random combinations of 10 variables were fitted to the Lassa fever data. Three combinations of absenceratiopresence clusters were used in each of Models 2 and 3, the 2 absenceratio1 presence cluster combination giving what appeared to be the best result. Model 1 showed that the recorded outbreaks of Lassa fever in human populations occurred in zones receiving between 1,500 and 3,000 mm rainfall annually. Rainfall, and to a much lesser extent temperature variables, were most strongly selected in both Models 2 and 3, and

  7. Risk Maps of Lassa Fever in West Africa

    Science.gov (United States)

    Fichet-Calvet, Elisabeth; Rogers, David John

    2009-01-01

    Background Lassa fever is caused by a viral haemorrhagic arenavirus that affects two to three million people in West Africa, causing a mortality of between 5,000 and 10,000 each year. The natural reservoir of Lassa virus is the multi-mammate rat Mastomys natalensis, which lives in houses and surrounding fields. With the aim of gaining more information to control this disease, we here carry out a spatial analysis of Lassa fever data from human cases and infected rodent hosts covering the period 1965–2007. Information on contemporary environmental conditions (temperature, rainfall, vegetation) was derived from NASA Terra MODIS satellite sensor data and other sources and for elevation from the GTOPO30 surface for the region from Senegal to the Congo. All multi-temporal data were analysed using temporal Fourier techniques to generate images of means, amplitudes and phases which were used as the predictor variables in the models. In addition, meteorological rainfall data collected between 1951 and 1989 were used to generate a synoptic rainfall surface for the same region. Methodology/Principal Findings Three different analyses (models) are presented, one superimposing Lassa fever outbreaks on the mean rainfall surface (Model 1) and the other two using non-linear discriminant analytical techniques. Model 2 selected variables in a step-wise inclusive fashion, and Model 3 used an information-theoretic approach in which many different random combinations of 10 variables were fitted to the Lassa fever data. Three combinations of absence∶presence clusters were used in each of Models 2 and 3, the 2 absence∶1 presence cluster combination giving what appeared to be the best result. Model 1 showed that the recorded outbreaks of Lassa fever in human populations occurred in zones receiving between 1,500 and 3,000 mm rainfall annually. Rainfall, and to a much lesser extent temperature variables, were most strongly selected in both Models 2 and 3, and neither vegetation nor

  8. Dust aerosol radiative effect and forcing over West Africa : A case study from the AMMA SOP

    Science.gov (United States)

    Lemaître, C.; Flamant, C.; Pelon, J.; Cuesta, J.; Chazette, P.; Raut, J. C.

    2009-04-01

    The massive transport of arid dust by the African easterly jet (AEJ) can impact the dynamic of the AEJ and modify the development of westerly African waves through modifications of horizontal temperature gradient. Hence, it is important to evaluate the radiative impact of dust and their effect on thermodynamical properties of the AEJ. In this presentation, the impact of aerosol on solar and infra-red fluxes and the heating rate due to dust over West Africa are investigated using the radiative code STREAMER, as well as space-borne and airborne lidars (CALIPSO and LEANDRE 2, respectively) as well as dropsonde observations acquired during the African Monsoon Multidisciplinary Analysis Special Observing Period. Aircraft operations were conducted on 13 and 14 June 2006, over Benin and Niger. On these days the dust observed over Benin and Niger originated from the Bodélé depression and from West Sudan. In this study, we use aerosol extinction coefficient derived from lidar, as well as temperature, pressure and water vapour profiles derived from dropsondes as inputs to STREAMER. The surface albedo is obtained with MODIS. A series of runs was carried out on 13 and 14 June 2006, around mid-day, to investigate the dust radiative forcing as a function of latitude, from 6°N to 15°N, i.e. between the vegetated coast of the Guinea Gulf and the arid Sahel. In the solar spectrum, the maximum heating rate associated with the dust plume on these days was comprised between 1.5 K/day and 3 K/day, depending on the aerosol load, over the entire Sudanian and Sahel regions as inferred from CALIPSO. Sensitivity studies to surface albedo, aerosol backscatter-to-extinction ratio, temperature and water vapor mixing ratio profiles were also conducted.

  9. Potential risk of regional disease spread in West Africa through cross-border cattle trade.

    Directory of Open Access Journals (Sweden)

    Anna S Dean

    Full Text Available BACKGROUND: Transboundary animal movements facilitate the spread of pathogens across large distances. Cross-border cattle trade is of economic and cultural importance in West Africa. This study explores the potential disease risk resulting from large-scale, cross-border cattle trade between Togo, Burkina Faso, Ghana, Benin, and Nigeria for the first time. METHODS AND PRINCIPAL FINDINGS: A questionnaire-based survey of livestock movements of 226 cattle traders was conducted in the 9 biggest cattle markets of northern Togo in February-March 2012. More than half of the traders (53.5% operated in at least one other country. Animal flows were stochastically simulated based on reported movements and the risk of regional disease spread assessed. More than three quarters (79.2%, range: 78.1-80.0% of cattle flowing into the market system originated from other countries. Through the cattle market system of northern Togo, non-neighbouring countries were connected via potential routes for disease spread. Even for diseases with low transmissibility and low prevalence in a given country, there was a high risk of disease introduction into other countries. CONCLUSIONS: By stochastically simulating data collected by interviewing cattle traders in northern Togo, this study identifies potential risks for regional disease spread in West Africa through cross-border cattle trade. The findings highlight that surveillance for emerging infectious diseases as well as control activities targeting endemic diseases in West Africa are likely to be ineffective if only conducted at a national level. A regional approach to disease surveillance, prevention and control is essential.

  10. Decomposing Wealth-Based Inequalities in Under-Five Mortality in West Africa

    Directory of Open Access Journals (Sweden)

    Aristide Romaric BADO

    2015-10-01

    Full Text Available Background: This study aimed to analysis the inequalities of mortality of children under 5 years in West Africa by examining the determinants and contributing factors to the overall inequality concentration in these countries.Method: Data used came from the DHS surveys conducted in the six countries in West Africa: Burkina Faso (2010, Benin (2006, Cote d'Ivoire 2011, Ghana (2008, Mali (2006, Nigeria (2008 and Niger (2012. The concentration index (CI and Generalized Linear Model (GLM with logit link were used to access inequality.Results: The results show that in all countries, the poorest Q1 have the highest proportions of deaths: Nigeria (31.4%, Cote d'Ivoire (30.4% and Ghana (36.4%, over 30% of deaths of children under 5 years are among the chil-dren of the poorest (Q1 and the absolute differences of proportions Q1-Q5 are more than 20 points (25.8 in Ghana and 23.6 in Nigeria. The contributing factors of inequalities of child mortality were birth order, maternal age, parity and household size. Our findings also showed that the intensity of inequality varies from one country to another.Conclusion: The most important conclusion of this study is to reduce mortality in children under 5 years, it is needed to reduce economic and social inequalities and improve the country's economic and social condition. There is a need for monitoring and assessment inequalities by leading causes of death and morbidity among children in the region in order to advance in understanding the gaps and finding a way to reduce them in West Africa countries.

  11. The Quest for Honor and Citizenship in Post-Slavery Borgu (Benin)

    DEFF Research Database (Denmark)

    Hahonou, Eric Komlavi

    2015-01-01

    Post-slavery refers here to the legacies of the institution of slavery while old forms of servile condition have mostly disappeared or are waning. In Northern Benin, past inequalities and hierarchies have been reversed in a mere century. What remains today is the heritage of an ideology...... that is increasingly being contested in a number of forms. The paper explores the heritage of slavery in its cultural, spatial, social, economic, and political dimensions. The author sheds light on the concept of honor that is a central dimension of social and political life in West Africa. In nowadays Benin, Gando...

  12. Groundwater contamination in relation with the increasing urbanization rate in Africa. Case of Cotonou and Porto Novo (Benin).

    Science.gov (United States)

    Odeloui, Diane; Celle-Jeanton, Hélène; Huneau, Frédéric; Boukari, Moussa; Alassane, Abdelkarim; Garel, Emilie; Lavastre, Véronique; Bertrand, Guillaume

    2016-04-01

    More than one billion people in the world still have no access to sufficient resources in drinking water (United Nation, 2014). In particular, large cities in Africa have to face several problems: 1) population growth associated with the strongest urbanization rate increase (5% per year) of the world leading to a dramatic increase in good-quality water needs, 2) low levels of solid waste management and sanitation services, 3) insufficient or disconnected water supply services, 4) low knowledge of water resources availabilities. The situation in Benin is a relevant illustration of the problems that Africa has to face to. As many other coastal urban areas in Africa (Showers, 2002; Re et al., 2011), Cotonou and Porto Novo cities have seen a rapid increase of their population as these towns constitute a corridor of transit for the imports and the exports in the nearby countries. Hence, they are very attractive for job hunters, and constitute the administrative centers for the whole country. This rapid population growth amplifies the problem of water supply and may generate serious impacts on groundwater resources: depletion due to overexploitation, salinization due to seawater intrusion and pollution linked to human activities. In order to insure a safe water supply in the context of increasing urbanization and population in the coastal area of Cotonou and Porto Novo, the identification of the main sources of pollution is essential for the implementation of long-term water management procedures. Based on two field campaigns carried out in January-2012 (dry season) and August-2012 (rainy season), hydrochemical analysis have been realized on groundwater sampled from boreholes drilled in the CTA (Continental Terminal Aquifer) and wells dug in the QCA (Quaternary Coastal Aquifer) in order to investigate the origin of salinization and the present time extension of the nitrate contamination. Historical data have also been collected from previous studies in order to

  13. Markets, Climate Change and Food Security in West Africa

    Science.gov (United States)

    Brown, Molly E.; Hintermann, Beat; Higgins, Nathaniel

    2009-01-01

    West Africa is one of the most food insecure regions of the world. Sharply increased food and energy prices in 2008 brought the role of markets in food access and availability around the world into the spotlight, particularly in urban areas. The period of high prices had the immediate consequence of sharply increasing the number of hungry people in the region without boosting farmer incomes significantly. In this article, the interaction between markets, food prices, agricultural technology and development is explored in the context of West Africa. To improve food security in West Africa, sustained commitment to investment in the agriculture sector will be needed to provide some protection against global swings in both production and world markets. Climate change mitigation programs are likely to force global energy and commodity price increases in the coming decades, putting pressure on regions like West Africa to produce more food locally to ensure stability in food security for the most vulnerable.

  14. Forest gradients in West Africa. A spatial gradient analysis.

    NARCIS (Netherlands)

    Rompaey, van R.S.A.R.

    1993-01-01

    The tropical rain forests of West Africa, west of the Dahomey interval, once covered some 40 million ha. Being on the western fringe of the African continent, they receive abundant rainfall from the SW monsoon. Further inland, rainfall gradually decreases and the forests give way to savanna and ulti

  15. Postprocessing of simulated precipitation for impact research in West Africa. Part II: A weather generator for daily data

    Science.gov (United States)

    Paeth, Heiko; Diederich, Malte

    2011-04-01

    Data from global and regional climate models refer to grid cells and, hence, are basically different from station data. This particularly holds for variables with enhanced spatio-temporal variability like precipitation. On the other hand, many applications like for instance hydrological models require atmospheric data with the statistical characteristics of station data. Here, we present a dynamical-statistical tool to construct virtual station data based on regional climate model output for tropical West Africa. This weather generator (WEGE) incorporates daily gridded rainfall from the model, an orographic term and a stochastic term, accounting for the chaotic spatial distribution of local rain events within a model grid box. In addition, the simulated probability density function of daily precipitation is adjusted to available station data in Benin. It is also assured that the generated data are still consistent with other model parameters like cloudiness and atmospheric circulation. The resulting virtual station data are in excellent agreement with various observed characteristics which are not explicitly addressed by the WEGE algorithm. This holds for the mean daily rainfall intensity and variability, the relative number of rainless days and the scaling of precipitation in time. The data set has already been used successfully for various climate impact studies in Benin.

  16. AMMA-CATCH studies in the Sahelian region of West-Africa: An overview

    Science.gov (United States)

    Lebel, Thierry; Cappelaere, Bernard; Galle, Sylvie; Hanan, Niall; Kergoat, Laurent; Levis, Samuel; Vieux, Baxter; Descroix, Luc; Gosset, Marielle; Mougin, Eric; Peugeot, Christophe; Seguis, Luc

    2009-08-01

    SummaryThe African Monsoon Multidisciplinary Analysis (AMMA) is an international and interdisciplinary experiment designed to investigate the interactions between atmospheric, oceanic and terrestrial systems and their joint controls on tropical monsoon dynamics in West Africa. This special issue reports results from a group of AMMA studies regrouped in the component " Couplage de l'Atmosphère Tropicale et du Cycle Hydrologique" (CATCH). AMMA-CATCH studies focus on measuring and understanding land surface properties and processes in West Africa, the role of terrestrial systems in altering boundary layer dynamics, and thus the potential that surface hydrology and biology, and human land use practices, may directly or indirectly affect monsoon dynamics and rainfall in the region. AMMA-CATCH studies focus on three intensively instrumented mesoscale sites in Mali, Niger and Benin that sample across the 100-1300 mm/annum rainfall gradient of the Sahel, Sudan and North-Guinean bioclimatic zones. Studies report on: (i) surface-boundary layer interactions that may influence atmospheric convergence and convective processes and thus rainfall type, timing and amount; (ii) vegetation dynamics at seasonal to decadal time-scales that may respond to, and alter, atmospheric processes; (iii) surface-atmosphere fluxes of heat, water and carbon dioxide that directly influence the atmosphere; (iv) soil moisture variability in space and time that provide the proximate control on vegetation activity, evapotranspiration and energy balance; and (v) local and mesoscale modeling of hydrology and land surface-atmosphere exchanges to assess their role in the hydrological, atmospheric and rainfall dynamics of West Africa. The AMMA-CATCH research reported in this issue will be extended in future years as measurements and analysis continue and are concluded within the context of both CATCH and the wider AMMA study. This body of research will contribute to an improved understanding of the

  17. Shrimp quality and safety management along the supply chain in Benin

    OpenAIRE

    Dabade, D.S.

    2015-01-01

    Abstract This thesis focuses on quality and safety management of tropical shrimp (Penaeus spp.) using Benin (West Africa) as an example of a shrimp exporting country. The entire supply chain, from fishing areas (brackish waters) to shrimp processing plants, was investigated. The steps of the chain prior to shrimp processing at the freezer plants were critical for shrimp quality and safety because of prevailing temperature abuse and inappropriate hygienic conditions. Combining culture-dependen...

  18. The potential of hybrid gravimetry for hydrology; application to a sudanian catchment (West Africa)

    Science.gov (United States)

    Hector, B.; Hinderer, J.; Séguis, L.

    2014-12-01

    The temporal and spatial variations of water storage are major unknowns of the hydrological cycle. They define the state of a hydrological system, which is critical for budget and process studies, like for instance threshold-governed subsurface redistribution, or water availability for evapotranspiration. Ground-based gravity measurements provide integrated (on a few tens of meters radius, the 'plot' scale) response to water storage changes (WSC) signal, which depends on mass and location changes of underground water. This information may be used for instance for process identification, for budget estimates, for specific yield retrieval, or for hypothesis testing through hydrological modeling. We try to address some of these issues based on our experience of a small catchment in the hard-rock Sudanian area of West-Africa (Djougou, northern Benin), where three state-of-art gravimeters have been deployed: a GWR superconducting gravimeter (SG), a Micro-g FG5 absolute gravimeter and a Scintrex CG5 microgravimeter. Spatial (i.e. at the catchment scale) distribution of WSC may be obtained using a hybrid gravimetry (CG5 + SG) approach. Significant hydrological information may be gained from gravity measurements, as long as these are analyzed in a joint approach, together with near-surface geophysics and hydrological monitoring for instance.

  19. Briefing : West Africa and its oil

    NARCIS (Netherlands)

    Ellis, S.D.K.

    2003-01-01

    The US war on terrorism and preparations for war against Iraq have enormously increased the strategic value of West African oil reserves. This comes at a time when there have been massive new discoveries in offshore waters. This article focuses on the increased US interests in West African oil. It e

  20. The lion in West Africa is critically endangered.

    Directory of Open Access Journals (Sweden)

    Philipp Henschel

    Full Text Available The African lion has declined to 500 km² PAs and compiled evidence of lion presence/absence for a further eight PAs. All PAs were situated within Lion Conservation Units, geographical units designated as priority lion areas by wildlife experts at a regional lion conservation workshop in 2005. Lions were confirmed in only 4 PAs, and our results suggest that only 406 (273-605 lions remain in West Africa, representing <250 mature individuals. Confirmed lion range is estimated at 49,000 km², or 1.1% of historical range in West Africa. PAs retaining lions were larger than PAs without lions and had significantly higher management budgets. We encourage revision of lion taxonomy, to recognize the genetic distinctiveness of West African lions and highlight their potentially unique conservation value. Further, we call for listing of the lion as critically endangered in West Africa, under criterion C2a(ii for populations with <250 mature individuals. Finally, considering the relative poverty of lion range states in West Africa, we call for urgent mobilization of investment from the international community to assist range states to increase management effectiveness of PAs retaining lions.

  1. An interventional model to develop health professionals in West Africa

    OpenAIRE

    Sanou, Anselme Simeon; Awoyale, Florence Adeola; Diallo, Abdoulaye

    2014-01-01

    The health sector is characterized by a human resource base lacking in numbers, specialized skills, and management skills. West African Health Organization (WAHO) recognizes the need within the West Africa sub-region for bilingual professionals who are skilled in public health, management, leadership, and information technology to build human capacity in public health and developed the Young Professionals Internship Program (YPIP). Our study explores the evolution of the programme. YPIP progr...

  2. The lion in West Africa is critically endangered.

    Science.gov (United States)

    Henschel, Philipp; Coad, Lauren; Burton, Cole; Chataigner, Beatrice; Dunn, Andrew; MacDonald, David; Saidu, Yohanna; Hunter, Luke T B

    2014-01-01

    The African lion has declined to lions from other extant African populations. Interventions to save West African lions are urgently required. However formulating effective conservation strategies has been hampered by a lack of data on the species' current distribution, status, and potential management deficiencies of protected areas (PAs) harboring lions. Our study synthesized available expert opinion and field data to close this knowledge gap, and formulate recommendations for the conservation of West African lions. We undertook lion surveys in 13 large (>500 km²) PAs and compiled evidence of lion presence/absence for a further eight PAs. All PAs were situated within Lion Conservation Units, geographical units designated as priority lion areas by wildlife experts at a regional lion conservation workshop in 2005. Lions were confirmed in only 4 PAs, and our results suggest that only 406 (273-605) lions remain in West Africa, representing lion range is estimated at 49,000 km², or 1.1% of historical range in West Africa. PAs retaining lions were larger than PAs without lions and had significantly higher management budgets. We encourage revision of lion taxonomy, to recognize the genetic distinctiveness of West African lions and highlight their potentially unique conservation value. Further, we call for listing of the lion as critically endangered in West Africa, under criterion C2a(ii) for populations with lion range states in West Africa, we call for urgent mobilization of investment from the international community to assist range states to increase management effectiveness of PAs retaining lions.

  3. Sensory diversity of fonio landraces from West Africa

    NARCIS (Netherlands)

    Fliedel, G.; Koreissi, Y.; Boré, F.; Dramé, D.; Brouwer, I.D.

    2013-01-01

    This study aims to establish if there is some sensory variability among fonio landraces. Fonio, the oldest indigenous and very tasty cereal growing in West Africa, is usually consumed as a couscous. Group interviews of consumers were conducted in Bamako, Mali to identify the main quality criteria of

  4. The epidemiology and control of onchocerciasis in West-Africa

    NARCIS (Netherlands)

    J.H.F. Remme

    1989-01-01

    textabstractThe present thesis deals with research which has been undertaken since 1983 with the aim of finding answers to the three main epidemiological questions which have been discussed above, i.e. I.-What are the epidemiological patterns of ocular onchocerciasis in West Africa and what is the g

  5. AMMA-CATCH a Hydrological, Meteorological and Ecological Long Term Observatory on West Africa : Some Recent Results

    Science.gov (United States)

    Galle, S.; Grippa, M.; Peugeot, C.; Bouzou Moussa, I.; Cappelaere, B.; Demarty, J.; Mougin, E.; Lebel, T.; Chaffard, V.

    2015-12-01

    AMMA-CATCH is a multi-scale observation system dedicated to long-term monitoring of the water cycle, the vegetation dynamics and their interaction with climate and water resources in West Africa. In the context of the global change, long-term observations are required to i) gain understanding in eco-hydrological processes over this highly contrasted region, ii) help their representation in Earth System Models, and iii) detect trends and infer their impacts on water resources and living conditions. It is made of three meso-scale sites (~ 1°x1°) in Mali, Niger and Benin, extending along the West African eco-climatic gradient. Within this regional window (5° by 9°), each of the three sites comprises a multi-scale set-up which helps documenting the components of the hydrologic budget and the evolutions of the surface conditions over a range of time scales: raingages, piezometers, river discharge stations, soil moisture and temperature profiles, turbulent fluxes measurements, LAI/biomass monitoring. This observation system has been continuously generating coherent datasets for 10 to 25 years depending on the datasets. It is jointly operated by French and African (Mali, Niger and Benin) research institutions. The data-base is available to the community through the website (www.amma-catch.org). AMMA-CATCH is a member of the French critical zone observatory network "Réseau des Bassins Versants", (RBV). AMMA-CATH participates to several global or regional observation networks, such as FluxNet, CarboAfrica, International Soil Moisture Networks (ISMN) and to calibration/validation campaigns for satellite missions such as SMOS (CNES, ESA), MEGHA-TROPIQUES (France/India) or SWAP(NASA). AMMA-CATCH fills a gap over a region, West Africa, where environmental data are largely lacking, and thus, it can usefully contribute to the international networking effort for environmental monitoring and research. Recent results on regional evolution of land cover, rainfall intensity and

  6. Distribution of knock-down resistance mutations in Anopheles gambiae molecular forms in west and west-central Africa

    Directory of Open Access Journals (Sweden)

    Caccone Adalgisa

    2008-04-01

    Full Text Available Abstract Background Knock-down resistance (kdr to DDT and pyrethroids in the major Afrotropical vector species, Anopheles gambiae sensu stricto, is associated with two alternative point mutations at amino acid position 1014 of the voltage-gated sodium channel gene, resulting in either a leucine-phenylalanine (L1014F, or a leucine-serine (L1014S substitution. In An. gambiae S-form populations, the former mutation appears to be widespread in west Africa and has been recently reported from Uganda, while the latter, originally recorded in Kenya, has been recently found in Gabon, Cameroon and Equatorial Guinea. In M-form populations surveyed to date, only the L1014F mutation has been found, although less widespread and at lower frequencies than in sympatric S-form populations. Methods Anopheles gambiae M- and S-form specimens from 19 sites from 11 west and west-central African countries were identified to molecular form and genotyped at the kdr locus either by Hot Oligonucleotide Ligation Assay (HOLA or allele-specific PCR (AS-PCR. Results The kdr genotype was determined for about 1,000 An. gambiae specimens. The L1014F allele was found at frequencies ranging from 6% to 100% in all S-form samples (N = 628, with the exception of two samples from Angola, where it was absent, and coexisted with the L1014S allele in samples from Cameroon, Gabon and north-western Angola. The L1014F allele was present in M-form samples (N = 354 from Benin, Nigeria, and Cameroon, where both M- and S-forms were sympatric. Conclusion The results represent the most comprehensive effort to analyse the overall distribution of the L1014F and L1014S mutations in An. gambiae molecular forms, and will serve as baseline data for resistance monitoring. The overall picture shows that the emergence and spread of kdr alleles in An. gambiae is a dynamic process and that there is marked intra- and inter-form heterogeneity in resistance allele frequencies. Further studies are needed to

  7. Education and Koranic Literacy in West Africa

    OpenAIRE

    Easton, Peter

    1999-01-01

    The note examines the practical, and literate skills that students acquire at different levels in West African Koranic schools. It is a long-standing parallel system of education, yet, relatively unknown to development planers, thus seldom taken into explicit account in their policies, and strategies. Islamic educational systems have been present since the seventh century, and by the tenth ...

  8. Hybrid Gravimetry for the Monitoring of Water Storage Changes in the Critical Zone of West Africa

    Science.gov (United States)

    Hector, B.; Hinderer, J.; Séguis, L.; Calvo, M.; Pfeffer, J.

    2015-12-01

    Time-lapse gravimetry is known to be a powerful tool to monitor mass redistributions near the Earth's surface and hence is of interest in various fields (volcanology, hydrology, glaciology, geothermics, C02 sequestration). Hybrid gravimetry relies on the combined use of different types of instruments measuring the earth's gravity changes i.e. relative spring gravimeters (RG) and superconducting gravimeters (SG), as well as ballistic absolute gravimeters (AG) in a specific study. We show here that hybrid gravimetry is able to provide new constraints on underground water storage changes. We will focus on two special cases in West Africa which were investigated in the frame of the GHYRAF (Gravity and Hydrology in Africa) project: one is located in the semi-arid Sahelian zone in Wankama (Niger) and another one in Djougou (Benin) in the humid, hard-rock basement zone. In Wankama, both time-lapse AG and RG are available. In an innovative field survey during 3 months of the rainy season in 2009, we merged relative microgravimetry on a network of 12 stations, magnetic resonance soundings, and hydrological measurements to evaluate both surface and subsurface water storage variations. We show that most of the gravity variations originate from heterogeneities in the vadose zone highlighting the potential of time lapse microgravity surveys for detecting intraseasonal water storage variations in the critical zone. In Djougou, we will present the hydrology results coming from the use of the hybrid gravimetry approach based on a continuous record of a GWR SG installed since 2010 complemented with FG5 AG episodic measurements (4 times a year between 2008 and 2011 then yearly). In addition we also set up repeated micro-gravimetric measurements with a Scintrex CG5 RG on a dense network (more than 100 surveys and 15 stations) around the base station. The continuous SG record allows to bring additional insight on the space and time variable gravity (and hence water storage changes) in

  9. An overview of the nutrition transition in West Africa: implications for non-communicable diseases.

    Science.gov (United States)

    Bosu, William K

    2015-11-01

    The nutrition landscape in West Africa has been dominated by the programmes to address undernutrition. However, with increasing urbanisation, technological developments and associated change in dietary patterns and physical activity, childhood and adult overweight, and obesity are becoming more prevalent. There is an evidence of increasing intake of dietary energy, fat, sugars and protein. There is low consumption of fruit and vegetables universally in West Africa. Overall, the foods consumed are predominantly traditional with the component major food groups within recommended levels. Most of the West African countries are at the early stages of nutrition transition but countries such as Cape Verde, Ghana and Senegal are at the latter stages. In the major cities of the region, children consume energy-dense foods such as candies, ice cream and sweetened beverages up to seven times as frequently as fruit and vegetables. Adult obesity rates have increased by 115 % in 15 years since 2004. In Ghana, the prevalence of overweight/obesity in women has increased from 12·8 % in 1993 to 29·9 % in 2008. In Accra, overweight/obesity in women has increased from 62·2 % in 2003 to 64·9 % in 2009. The age-standardised proportion of adults who engage in adequate levels of physical activity ranges from 46·8 % in Mali to 94·7 % in Benin. The lingering stunting in children and the rising overweight in adults have resulted to a dual burden of malnutrition affecting 16·2 % of mother-child pairs in Cotonou. The prevalence of hypertension has been increased and ranges from 17·6 % in Burkina Faso to 38·7 % in Cape Verde. The prevalence is higher in the cities: 40·2 % in Ougadougou, 46·0 % in St Louis and 54·6 % in Accra. The prevalence of diabetes ranges from 2·5 to 7·9 % but could be as high as 17·9 % in Dakar, Senegal. The consequences of nutrition transition are not only being felt by the persons in the high socioeconomic class, but also in cities such as Accra and

  10. Potential Climate Effects of Dust Aerosols' over West Africa

    Science.gov (United States)

    JI, Z.; Wang, G.; Pal, J. S.; Yu, M.

    2014-12-01

    Climate in West Africa is under the influence of the West African monsoon circulation and mineral dust emitted from the Sahara desert (which is the world's largest source of mineral dust emission). Dust aerosols alter the atmospheric radiative fluxes and act as cloud condensation nuclei in the process of emission, transportation and deposition. However, our understanding regarding how dust aerosols influence the present-day and future climate of West Africa is very limited. In this study, a regional climate model RegCM4.3.4-CLM4.5 is used to investigate the potential climatic effects of dust aerosols both in present (1981-2000) and future (2081-2100) periods over WA. First, the model performance and dust climatic effects are evaluated. The contribution of dust climatic effects under RCP8.5 scenario and their confounding effects with land use change are assessed. Our results indicate that the model can reproduce with reasonable accuracy the spatial and temporal distribution of climatology, aerosol optical depth and surface concentration over WA. The shortwave radiative forcing of dust is negative in the surface and positive in the atmosphere, with greater changes in JJA and MAM compared to those in SON and DJF. Over most of West Africa, cooling is the dominant effect on temperature. Their impact on precipitation features a dipole pattern, with decrease in the north and increase in the south of West Africa. Despite the dust-induced decrease of precipitation amount, dusts cause extreme precipitation to increase. To evaluate the uncertainties surrounding our modeling results, sensitivity experiments driven by ICBC from MIROC-ESM and CESM and their dynamic downscaling results are used for comparisons. Results from these sensitivity experiments indicate that the impact of dust aerosols on present and future climate is robust.

  11. Forest gradients in West Africa. A spatial gradient analysis.

    OpenAIRE

    Rompaey, van, R.S.A.R.

    1993-01-01

    The tropical rain forests of West Africa, west of the Dahomey interval, once covered some 40 million ha. Being on the western fringe of the African continent, they receive abundant rainfall from the SW monsoon. Further inland, rainfall gradually decreases and the forests give way to savanna and ultimately to the Sahara desert.This Upper Guinea forest block used to cover most of Liberia and parts of Côte d'Ivoire and Ghana. Here, deforestation rates are among the fastest in the world. Humans h...

  12. Research needs for lion conservation in West and Central Africa.

    Science.gov (United States)

    Bauer, Hans; De Iongh, Hans H; Princée, Frank P; Ngantou, Daniel

    2003-08-01

    The lion has historically probably been widespread at low densities in West and Central Africa, nowadays they are largely restricted to small isolated populations inside protected areas. The total number is probably between 1200 and 2700, the best possible guesstimate would be 1700. Mankind is the main cause for the suspected decline of lion populations, both inside and outside protected areas. Very little research has been done on West and Central African lions a few examples are summarized here. The international community is slowly becoming aware of threats to lions in the region and some initiatives for lion conservation have started.

  13. Sensory diversity of fonio landraces from West Africa

    OpenAIRE

    Fliedel, G.; Koreissi, Y.; Boré, F.; Dramé, D.; Brouwer, I.D.

    2013-01-01

    This study aims to establish if there is some sensory variability among fonio landraces. Fonio, the oldest indigenous and very tasty cereal growing in West Africa, is usually consumed as a couscous. Group interviews of consumers were conducted in Bamako, Mali to identify the main quality criteria of a cooked grain. Fonio grain must be swollen, not sticky with a soft consistency, pale and containing low impurities. Sensory properties of 20 fonio landraces from Mali, Guinea and Burkina Faso wer...

  14. Human Security and Developmental Crisis in the Contemporary West Africa

    OpenAIRE

    Ayodeji A. Aduloju; Omowunmi O. Pratt

    2014-01-01

    The last two decades were characterized by severe conflicts in the West Africa subregion. The era of conflict resolution, management and peace building thus came to define theregion. The destruction left by long years of protracted conflicts and the present state of devel opment is reason enough to warrant attention both from within and beyond. The study expounds, operationalizes and clarifies the concept of human security and development, and how human security issues lead to underdevelopmen...

  15. Intense convection over West Africa during AMMA SOP3 experiment

    Science.gov (United States)

    Lenouo, André; Sall, Saïdou Moustapha; Badiane, Daouda; Gaye, Amadou Thierno; Kamga Mkankam, F.

    2016-11-01

    ERA-Interim product from the European Center for Medium-Range Weather Forecast (ECMWF) assimilation of African Monsoon Multidisciplinary Analysis (AMMA) resources, Meteosat satellite images, and synoptic observations were used to study local- and regional-scale environments associated with intense convective systems during the AMMA-SOP3 experiment over West Africa in the Northern Hemisphere of summer 2006. The convective system, from the 21st to 23rd of August 2006, was more active at 0000 and 1800 UTC showing diurnal cycle of deep convection over West Africa where the African easterly waves (AEWs) are developed downstream. Downstream barotropic and baroclinic energy conversions associated with strong AEWs are important for the maintenance of AEW activity in West Africa. Barotropic energy conversions dominate south of the African easterly jet (AEJ), while baroclinic energy conversions are most important north of the AEJ. From a dynamical viewpoint, the low-level vorticity presents strong positive values over the sea and Sahara zone, indicating that exists on the cyclonic shear side of the African easterly jet, which is consistent with baroclinic growth. The 925-hPa equivalent potential temperature structure show a maximum over the Sahara which corresponds to the depression observed in this region. A mosaic of three hourly infrared (IR) satellite images, depicts a very distinct signal from an initial region of convection, developing through several stages and moving off the African coast. These observations, along with those available from the World Weather Watch, provide an opportunity to carry out numerical weather prediction (NWP) studies over West Africa utilizing high resolution limited area models.

  16. Seasonal TEC Variability in West Africa Equatorial Anomaly Region

    OpenAIRE

    ZOUNDI, Christian; Ouattara, Fréderic; FLEURY, Rolland; Amory-Mazaudier, Christine; Lassudrie-Duchesne, Patrick

    2012-01-01

    This paper presented the seasonal variability of TEC/ GPS data recorded at Ouagadougou a West Africa GPS station located near the magnetic equator. Seasonal data TEC time variations are compared to those of TEC derived from IGS GPS network maps. The present study showed that TEC map model predicts well data TEC during equinoctial months and fairly well during solstice months. The best prediction is obtained during spring and the worst during winter. The analysis of seasonal TEC profiles highl...

  17. Economics of Malaria Prevention in US Travelers to West Africa

    OpenAIRE

    Adachi, Kenji; Coleman, Margaret S.; Khan, Nomana; Jentes, Emily S.; Arguin, Paul; Rao, Sowmya R.; Regina C LaRocque; Sotir, Mark J.; Brunette, Gary; Ryan, Edward T.; Meltzer, Martin I.

    2013-01-01

    Background. Pretravel health consultations help international travelers manage travel-related illness risks through education, vaccination, and medication. This study evaluated costs and benefits of that portion of the health consultation associated with malaria prevention provided to US travelers bound for West Africa. Methods. The estimated change in disease risk and associated costs and benefits resulting from traveler adherence to malaria chemoprophylaxis were calculated from 2 perspectiv...

  18. Economics of Malaria Prevention in US Travelers to West Africa

    OpenAIRE

    Adachi, Kenji; Coleman, Margaret S.; Khan, Nomana; Jentes, Emily S.; Arguin, Paul; Rao, Sowmya R.; Regina C LaRocque; Sotir, Mark J.; Brunette, Gary; Ryan, Edward T.; Meltzer, Martin I.; ,

    2013-01-01

    Background.  Pretravel health consultations help international travelers manage travel-related illness risks through education, vaccination, and medication. This study evaluated costs and benefits of that portion of the health consultation associated with malaria prevention provided to US travelers bound for West Africa. Methods.  The estimated change in disease risk and associated costs and benefits resulting from traveler adherence to malaria chemoprophylaxis were calculated from 2 perspect...

  19. Vaccination against pneumococcus in West Africa: perspectives and prospects

    Directory of Open Access Journals (Sweden)

    Donkor ES

    2013-09-01

    Full Text Available Eric S Donkor,1 Nicholas TKD Dayie,1,2 Ebenezer V Badoe3 1Department of Microbiology, University of Ghana Medical School, Accra, Ghana; 2Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; 3Department of Child Health, University of Ghana Medical School, Accra, Ghana Background: Pneumococcal vaccination has become obligatory due to the enormous burden of pneumococcal diseases. Quite recently, pneumococcal conjugate vaccines have been developed, and have been shown to be superior to the previous polyvalent polysaccharide vaccine of the organism. Pneumococcal conjugate vaccines (PCVs are being introduced in many West African countries and it is important to understand the expected performance, relevance, and limitations of these vaccines in the subregion. Aim: The objective of the study presented here was to provide epidemiological insights into PCVs in West Africa based on the prevailing pneumococcal serotypes in the subregion. Methods: A systematic review was carried out on pneumococcal serotypes causing invasive and noninvasive diseases in West Africa. Studies included in the review were those that reported at least 20 serotyped pneumococcal isolates and which were conducted prior to the introduction of PCVs in the region in 2009. The proportion of pneumococcal disease associated with each serotype as well as the serotype coverage of various PCVs (PCV7, PCV10, and PCV13 were calculated. Results: The data covered 718 serotyped pneumococcal isolates from six West African countries: Burkina Faso, Ghana, Nigeria, Mali, Senegal, and The Gambia. The 718 isolates covered more than 20 serotypes. Serotype 1 was the most prevalent serotype (32%, followed by serotype 5 (15%, serotype 6 (7%, serotype 2 (6%, serotype 3 (6%, and serotype 12 (5%. The estimated serotype coverage of PCVs among the West African countries was 2%–36% for PCV7, 39%–80% for PCV10, and 65%–87% for PCV13

  20. A new inventory for two-wheel vehicle emissions in West Africa for 2002

    Science.gov (United States)

    Assamoi, Eric-Michel; Liousse, Catherine

    2010-10-01

    database does not properly account for regional specificities. Moreover, emission factors for black carbon (BC) and primary organic carbon (OCp) have been measured for two-stroke engines in Benin (Guinot, B., Liousse, C., Cachier, H., Guillaume, B., et al. New emission factor estimates for biofuels and mobile sources. Atmospheric Environment, in press.), giving significantly higher values than in Europe. This is particularly true for OCp, and consequently the calculated emissions for two-stroke engines are also significantly larger than total road traffic previously estimated in global inventories ( Junker and Liousse (2008) with United Nations database for 2002; Bond et al., 2004). The ensuing discussion illustrates the importance of two-stroke engines in the West Africa transport sector and the strong need for inventory updating.

  1. Nuclear axis. Secret collaboration between West Germany and South Africa

    International Nuclear Information System (INIS)

    Today there is virtually no doubt that the white racist minority government in Pretoria has-or shortly will have-its finger on the nuclear button, introducing a new and extremely volatile element into African politics and threatening the peace of the whole world. This book is the sinister story of how they are getting the bomb and who has helped them. Relying on hitherto top-secret government documents, informants, and the public record, Zdenek Cervenka of the Scandinavian Institute of Africa Affairs, and Barbara Rogers, formerly of the British Foreign Office and a consultant to the United Nations and the Congressional Subcommittee on Southern Africa, have pieced together the story of the clandestine collaboration between West Germany, and South Africa to develop operational nuclear weapons. The authors trace Germany's rise as a military nuclear power (only thirty years after unconditional surrender); the growth of its atomic cooperation with South Africa; the transfer of secret technological data; the way in which other countries-including the United States, Britain, France, Israel-have been involved. The authors show that the Germans, pledged never to develop nuclear weapons, have become a major nuclear power, and, together with the South African military-industrial complex, now have the power to alter the course of modern history in Europe, Africa, and the rest of the world. The authors conclude with a discussion of how the international system of nuclear safeguards failed and how the Western allies acquiesced in that failure

  2. Nuclear axis. Secret collaboration between West Germany and South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Cervenka, Z.; Rogers, B.

    1978-01-01

    Today there is virtually no doubt that the white racist minority government in Pretoria has-or shortly will have-its finger on the nuclear button, introducing a new and extremely volatile element into African politics and threatening the peace of the whole world. This book is the sinister story of how they are getting the bomb and who has helped them. Relying on hitherto top-secret government documents, informants, and the public record, Zdenek Cervenka of the Scandinavian Institute of Africa Affairs, and Barbara Rogers, formerly of the British Foreign Office and a consultant to the United Nations and the Congressional Subcommittee on Southern Africa, have pieced together the story of the clandestine collaboration between West Germany, and South Africa to develop operational nuclear weapons. The authors trace Germany's rise as a military nuclear power (only thirty years after unconditional surrender); the growth of its atomic cooperation with South Africa; the transfer of secret technological data; the way in which other countries-including the United States, Britain, France, Israel-have been involved. The authors show that the Germans, pledged never to develop nuclear weapons, have become a major nuclear power, and, together with the South African military-industrial complex, now have the power to alter the course of modern history in Europe, Africa, and the rest of the world. The authors conclude with a discussion of how the international system of nuclear safeguards failed and how the Western allies acquiesced in that failure.

  3. Increasing Use of Postpartum Family Planning and the Postpartum IUD: Early Experiences in West and Central Africa.

    Science.gov (United States)

    Pleah, Tsigue; Hyjazi, Yolande; Austin, Suzanne; Diallo, Abdoulaye; Dao, Blami; Waxman, Rachel; Karna, Priya

    2016-08-11

    A global resurgence of interest in the intrauterine device (IUD) as an effective long-acting reversible contraceptive and in improving access to a wide range of contraceptive methods, as well as an emphasis on encouraging women to give birth in health care facilities, has led programs to introduce postpartum IUD (PPIUD) services into postpartum family planning (PPFP) programs. We describe strategic, organizational, and technical elements that contributed to early successes of a regional initiative in West and Central Africa to train antenatal, maternity, and postnatal care providers in PPFP counseling for the full range of available methods and in PPIUD service delivery. In November 2013, the initiative provided competency-based training in Guinea for providers from the main public teaching hospital in 5 selected countries (Benin, Chad, Côte d'Ivoire, Niger, and Senegal) with no prior PPFP counseling or PPIUD capacity. The training was followed by a transfer-of-learning visit and monitoring to support the trained providers. One additional country, Togo, replicated the initiative's model in 2014. Although nascent, this initiative has introduced high-quality PPFP and PPIUD services to the region, where less than 1% of married women of reproductive age use the IUD. In total, 21 providers were trained in PPFP counseling, 18 of whom were also trained in PPIUD insertion. From 2014 to 2015, more than 15,000 women were counseled about PPFP, and 2,269 women chose and received the PPIUD in Benin, Côte d'Ivoire, Niger, Senegal, and Togo. (Introduction of PPIUD services in Chad has been delayed.) South-South collaboration has been central to the initiative's accomplishments: Guinea's clinical centers of excellence and qualified trainers provided a culturally resonant example of a PPFP/PPIUD program, and trainings are creating a network of regional trainers to facilitate expansion. Two of the selected countries (Benin and Niger) have expanded their PPFP/PPUID training

  4. Increasing Use of Postpartum Family Planning and the Postpartum IUD: Early Experiences in West and Central Africa

    Science.gov (United States)

    Pleah, Tsigue; Hyjazi, Yolande; Austin, Suzanne; Diallo, Abdoulaye; Dao, Blami; Waxman, Rachel; Karna, Priya

    2016-01-01

    ABSTRACT A global resurgence of interest in the intrauterine device (IUD) as an effective long-acting reversible contraceptive and in improving access to a wide range of contraceptive methods, as well as an emphasis on encouraging women to give birth in health care facilities, has led programs to introduce postpartum IUD (PPIUD) services into postpartum family planning (PPFP) programs. We describe strategic, organizational, and technical elements that contributed to early successes of a regional initiative in West and Central Africa to train antenatal, maternity, and postnatal care providers in PPFP counseling for the full range of available methods and in PPIUD service delivery. In November 2013, the initiative provided competency-based training in Guinea for providers from the main public teaching hospital in 5 selected countries (Benin, Chad, Côte d’Ivoire, Niger, and Senegal) with no prior PPFP counseling or PPIUD capacity. The training was followed by a transfer-of-learning visit and monitoring to support the trained providers. One additional country, Togo, replicated the initiative’s model in 2014. Although nascent, this initiative has introduced high-quality PPFP and PPIUD services to the region, where less than 1% of married women of reproductive age use the IUD. In total, 21 providers were trained in PPFP counseling, 18 of whom were also trained in PPIUD insertion. From 2014 to 2015, more than 15,000 women were counseled about PPFP, and 2,269 women chose and received the PPIUD in Benin, Côte d’Ivoire, Niger, Senegal, and Togo. (Introduction of PPIUD services in Chad has been delayed.) South–South collaboration has been central to the initiative’s accomplishments: Guinea’s clinical centers of excellence and qualified trainers provided a culturally resonant example of a PPFP/PPIUD program, and trainings are creating a network of regional trainers to facilitate expansion. Two of the selected countries (Benin and Niger) have expanded their PPFP

  5. Quaternary forest associations in lowland tropical West Africa

    Science.gov (United States)

    Miller, Charlotte S.; Gosling, William D.

    2014-01-01

    Terrestrial fossil pollen records are frequently used to reveal the response of vegetation to changes in both regional and global climate. Here we present a fossil pollen record from sediment cores extracted from Lake Bosumtwi (West Africa). This record covers the last c. 520 thousand years (ka) and represents the longest terrestrial pollen record from Africa published to date. The fossil pollen assemblages reveal dynamic vegetation change which can be broadly characterized as indicative of shifts between savannah and forest. Savannah formations are heavily dominated by grass (Poaceae) pollen (>55%) typically associated with Cyperaceae, Chenopodiaceae-Amaranthaceae and Caryophyllaceae. Forest formations are palynologically more diverse than the savannah, with the key taxa occurring in multiple forest zones being Moraceae, Celtis, Uapaca, Macaranga and Trema. The fossil pollen data indicate that over the last c. 520 ka the vegetation of lowland tropical West Africa has mainly been savannah; however six periods of forest expansion are evident which most likely correspond to global interglacial periods. A comparison of the forest assemblage composition within each interglacial suggests that the Holocene (11-0 ka) forest occurred under the wettest climate, while the forest which occurred at the time of Marine Isotope Stage 7 probably occurred under the driest climate.

  6. Ethanol Production from Hydrothermally-Treated Biomass from West Africa

    DEFF Research Database (Denmark)

    Bensah, Edem C.; Kádár, Zsófia; Mensah, Moses Y.

    2015-01-01

    Despite the abundance of diverse biomass resources in Africa, they have received little research and development focus. This study presents compositional analysis, sugar, and ethanol yields of hydrothermal pretreated (195 degrees C, 10 min) biomass from West Africa, including bamboo wood, rubber...... wood, elephant grass, Siam weed, and coconut husk, benchmarked against those of wheat straw. The elephant grass exhibited the highest glucose and ethanol yields at 57.8% and 65.1% of the theoretical maximums, respectively. The results show that the glucose yield of pretreated elephant grass was 3.......5 times that of the untreated material, while the ethanol yield was nearly 2 times higher. Moreover, the sugar released by the elephant grass (30.8 g/100 g TS) was only slightly lower than by the wheat straw (33.1 g/100 g TS), while the ethanol yield (16.1 g/100 g TS) was higher than that of the straw (15...

  7. Putting farmers first: reshaping agricultural research in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Pimbert, Michel

    2012-01-15

    How agricultural research is funded, organised, controlled and practised can have a huge impact on small-scale producers in the global South. In many countries, such research is driven by external funds, priorities and technological fixes, such as hybrid seeds, which can erode crop diversity. But food producers across the world are beginning to raise their voices to ensure that agricultural research better meets their needs and priorities. A series of farmer assessments and citizens' juries in West Africa has helped farmers assess existing approaches and articulate recommendations for policy and practice to achieve their own vision of agricultural research. In 2012, a high-level policy dialogue between farmers and the Alliance for a Green Revolution in Africa hopes to take this discussion to the next level and develop a shared agenda that can serve development and the public good.

  8. Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy: The IeDEA-West Africa HIV-2 Cohort Study.

    Directory of Open Access Journals (Sweden)

    Didier K Ekouevi

    Full Text Available HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework of the International epidemiological Databases to Evaluate AIDS (IeDEA.We collected data on all HIV-2 and HIV-1/HIV-2 dually seropositive patients (both ARV-naive and starting ART and followed-up in clinical centres in the IeDEA-WA network including a total of 13 clinics in five countries: Benin, Burkina-Faso Côte d'Ivoire, Mali, and Senegal, in the West Africa region.Data was merged for 1,754 patients (56% female, including 1,021 HIV-2 infected patients (551 on ART and 733 dually seropositive for both HIV-1 and HIV 2 (463 on ART. At ART initiation, the median age of HIV-2 patients was 45.3 years, IQR: (38.3-51.7 and 42.4 years, IQR (37.0-47.3 for dually seropositive patients (p = 0.048. Overall, 16.7% of HIV-2 patients on ART had an advanced clinical stage (WHO IV or CDC-C. The median CD4 count at the ART initiation is 166 cells/mm(3, IQR (83-247 among HIV-2 infected patients and 146 cells/mm(3, IQR (55-249 among dually seropositive patients. Overall, in ART-treated patients, the CD4 count increased 126 cells/mm(3 after 24 months on ART for HIV-2 patients and 169 cells/mm(3 for dually seropositive patients. Of 551 HIV-2 patients on ART, 5.8% died and 10.2% were lost to follow-up during the median time on ART of 2.4 years, IQR (0.7-4.3.This large multi-country study of HIV-2 and HIV-1/HIV-2 dual infection in West Africa suggests that routine clinical care is less than optimal and that management and treatment of HIV-2 could be further informed by ongoing studies and randomized clinical trials in this population.

  9. Comparative financial analysis of electricity utilities in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Fritsch, Remi, E-mail: fritschr@afd.fr [Centre d' Etudes Financieres, Economiques et Bancaires (CEFEB), BP 33401, 13567 Marseille cedex 02 (France)

    2011-10-15

    Access to electricity is a major issue in West Africa. Governments have a difficult equation to solve. They naturally seek to offer their people a cheap kWh. But they are constrained by a production based largely on oil and therefore highly volatile production costs. How to fix an acceptable tariff, taking into account the investment needs required to expand the network and increase production? This analysis should provide some answers. The study presented in this paper provides a financial analysis of electricity utilities in West Africa. It allows a comparison of performances on a number of key financial ratios related to operations (Earning Before Interest Taxes Debt and Amortization/sales, working capital requirement/sales, days of receivables or payables), investment (net fixed assets/gross fixed assets), bank financing (financial structure, debt/EBITDA, interest expense/EBITDA) and economic and financial returns (Return On Capital Employed, Return On Equity). The conclusion focuses on the growth opportunity that the electricity sector could represent for each country. But this opportunity may only materialize if the EBITDA margins are restored. The available options appear limited and must be assessed taking into account the context of each country: tariff increase, improvement of technical losses or diversification into means of production no longer based primarily on oil or gas. - Highlights: > The study provides a financial analysis of electricity distribution companies in West Africa. > The study highlights generally insufficient EBITDA margins. > The study raises the question of tariffs and contribution to Gross Domestic Product of the electricity sector. > The conclusion focuses on the growth opportunity that the electricity sector could represent for each country.

  10. Comparative financial analysis of electricity utilities in West Africa

    International Nuclear Information System (INIS)

    Access to electricity is a major issue in West Africa. Governments have a difficult equation to solve. They naturally seek to offer their people a cheap kWh. But they are constrained by a production based largely on oil and therefore highly volatile production costs. How to fix an acceptable tariff, taking into account the investment needs required to expand the network and increase production? This analysis should provide some answers. The study presented in this paper provides a financial analysis of electricity utilities in West Africa. It allows a comparison of performances on a number of key financial ratios related to operations (Earning Before Interest Taxes Debt and Amortization/sales, working capital requirement/sales, days of receivables or payables), investment (net fixed assets/gross fixed assets), bank financing (financial structure, debt/EBITDA, interest expense/EBITDA) and economic and financial returns (Return On Capital Employed, Return On Equity). The conclusion focuses on the growth opportunity that the electricity sector could represent for each country. But this opportunity may only materialize if the EBITDA margins are restored. The available options appear limited and must be assessed taking into account the context of each country: tariff increase, improvement of technical losses or diversification into means of production no longer based primarily on oil or gas. - Highlights: → The study provides a financial analysis of electricity distribution companies in West Africa. → The study highlights generally insufficient EBITDA margins. → The study raises the question of tariffs and contribution to Gross Domestic Product of the electricity sector. → The conclusion focuses on the growth opportunity that the electricity sector could represent for each country.

  11. Laboratory Response to Ebola - West Africa and United States.

    Science.gov (United States)

    Sealy, Tara K; Erickson, Bobbie R; Taboy, Céline H; Ströher, Ute; Towner, Jonathan S; Andrews, Sharon E; Rose, Laura E; Weirich, Elizabeth; Lowe, Luis; Klena, John D; Spiropoulou, Christina F; Rayfield, Mark A; Bird, Brian H

    2016-01-01

    The 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa highlighted the need to maintain organized laboratory systems or networks that can be effectively reorganized to implement new diagnostic strategies and laboratory services in response to large-scale events. Although previous Ebola outbreaks enabled establishment of critical laboratory practice safeguards and diagnostic procedures, this Ebola outbreak in West Africa highlighted the need for planning and preparedness activities that are better adapted to emerging pathogens or to pathogens that have attracted little commercial interest. The crisis underscored the need for better mechanisms to streamline development and evaluation of new diagnostic assays, transfer of material and specimens between countries and organizations, and improved processes for rapidly deploying health workers with specific laboratory expertise. The challenges and events of the outbreak forced laboratorians to examine not only the comprehensive capacities of existing national laboratory systems to recognize and respond to events, but also their sustainability over time and the mechanisms that need to be pre-established to ensure effective response. Critical to this assessment was the recognition of how response activities (i.e., infrastructure support, logistics, and workforce supplementation) can be used or repurposed to support the strengthening of national laboratory systems during the postevent transition to capacity building and recovery. This report compares CDC's domestic and international laboratory response engagements and lessons learned that can improve future responses in support of the International Health Regulations and Global Health Security Agenda initiatives.The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html). PMID:27389781

  12. EPIVAC International Conference on Financial Sustainability of Immunization Programs in sub-Saharan Africa, February 16-18, 2012, Ouidah, Benin.

    Science.gov (United States)

    Drach, Marcel; Le Gargasson, Jean-Bernard; Mathonnat, Jacky; Da Silva, Alfred; Kaddar, Miloud; Colombini, Anaïs

    2013-09-23

    The introduction of new vaccines with much higher prices than traditional vaccines results in increasing budgetary pressure on immunization programs in GAVI-eligible countries, increasing the need to ensure their financial sustainability. In this context, the third EPIVAC (Epidemiology and Vaccinology) technical conference was held from February 16 to 18, 2012 at the Regional Institute of Public Health in Ouidah, Benin. Managers of ministries of health and finance from 11 West African countries (GAVI eligible countries), as well as former EPIVAC students and European experts, shared their knowledge and best practices on immunization financing at district and country level. The conference concluded by stressing five major priorities for the financial sustainability of national immunization programs (NIPs) in GAVI-eligible countries. - Strengthen public financing by increasing resources and fiscal space, improving budget processes, increasing contribution of local governments and strengthen efficiency of budget spending. - Promote equitable community financing which was recognized as a significant and essential contribution to the continuity of EPI operations. - Widen private funding by exploring prospects offered by sponsorship through foundations dedicated to immunization and by corporate social responsibility programs. - Contain the potential crowding-out effect of GAVI co-financing and ensure that decisions on new vaccine introductions are evidence-based. - Seek out innovative financing mechanisms such as taxes on food products or a national solidarity fund. PMID:23892101

  13. Insects used for animal feed in West Africa

    OpenAIRE

    Kenis, M.; Koné, N.; Chrysostome, C. A. A. M.; E. Devic; G.K.D. Koko; V.A. Clottey; S. Nacambo; G.A. Mensah

    2014-01-01

    In West Africa, as in many parts of the world, livestock and fish farming suffer from the increasing cost of feed, especially protein ingredients, which are hardly available for village poultry farming and small-scale fish farming. Insects, which are a natural food source of poultry and fish and are rich in protein and other valuable nutrients, can be used to improve animal diets, a practice which is now strongly promoted by the FAO as a tool for poverty alleviation. This paper reviews practi...

  14. Risk Maps of Lassa Fever in West Africa

    OpenAIRE

    Elisabeth Fichet-Calvet; David John Rogers

    2009-01-01

    BACKGROUND: Lassa fever is caused by a viral haemorrhagic arenavirus that affects two to three million people in West Africa, causing a mortality of between 5,000 and 10,000 each year. The natural reservoir of Lassa virus is the multi-mammate rat Mastomys natalensis, which lives in houses and surrounding fields. With the aim of gaining more information to control this disease, we here carry out a spatial analysis of Lassa fever data from human cases and infected rodent hosts covering the peri...

  15. Testing Modeling Assumptions in the West Africa Ebola Outbreak

    Science.gov (United States)

    Burghardt, Keith; Verzijl, Christopher; Huang, Junming; Ingram, Matthew; Song, Binyang; Hasne, Marie-Pierre

    2016-01-01

    The Ebola virus in West Africa has infected almost 30,000 and killed over 11,000 people. Recent models of Ebola Virus Disease (EVD) have often made assumptions about how the disease spreads, such as uniform transmissibility and homogeneous mixing within a population. In this paper, we test whether these assumptions are necessarily correct, and offer simple solutions that may improve disease model accuracy. First, we use data and models of West African migration to show that EVD does not homogeneously mix, but spreads in a predictable manner. Next, we estimate the initial growth rate of EVD within country administrative divisions and find that it significantly decreases with population density. Finally, we test whether EVD strains have uniform transmissibility through a novel statistical test, and find that certain strains appear more often than expected by chance. PMID:27721505

  16. Embargo on Lion Hunting Trophies from West Africa: An Effective Measure or a Threat to Lion Conservation?

    Science.gov (United States)

    Bouché, Philippe; Crosmary, William; Kafando, Pierre; Doamba, Benoit; Kidjo, Ferdinand Claude; Vermeulen, Cédric; Chardonnet, Philippe

    2016-01-01

    The W-Arly-Pendjari (WAP) ecosystem, shared among Benin, Burkina Faso and Niger, represents the last lion stronghold of West Africa. To assess the impact of trophy hunting on lion populations in hunting areas of the WAP, we analyzed trends in harvest rates from 1999 to 2014. We also investigated whether the hunting areas with higher initial hunting intensity experienced steeper declines in lion harvest between 1999 and 2014, and whether lion densities in hunting areas were lower than in national parks. Lion harvest rate remained overall constant in the WAP. At initial hunting intensities below 1.5 lions/1000km2, most hunting areas experienced an increase in lion harvest rate, although that increase was of lower magnitude for hunting areas with higher initial hunting intensity. The proportion of hunting areas that experienced a decline in lion harvest rate increased at initial hunting intensities above 1.5 lions/1000km2. In 2014, the lion population of the WAP was estimated with a spoor count at 418 (230-648) adults and sub-adult individuals, comparable to the 311 (123-498) individuals estimated in the previous 2012 spoor survey. We found no significant lion spoor density differences between national parks and hunting areas. Hunting areas with higher mean harvest rates did not have lower lion densities. The ratio of large adult males, females and sub-adults was similar between the national parks and the hunting areas. These results suggested that the lion population was not significantly affected by hunting in the WAP. We concluded that a quota of 1 lion/1000km2 would be sustainable for the WAP. Based on our results, an import embargo on lion trophies from the WAP would not be justified. It could ruin the incentive of local actors to conserve lions in hunting areas, and lead to a drastic reduction of lion range in West Africa.

  17. Validating modeled soil moisture with in-situ data for agricultural drought monitoring in West Africa

    Science.gov (United States)

    McNally, A.; Yatheendradas, S.; Jayanthi, H.; Funk, C. C.; Peters-Lidard, C. D.

    2011-12-01

    The declaration of famine in Somalia on July 21, 2011 highlights the need for regional hydroclimate analysis at a scale that is relevant for agropastoral drought monitoring. A particularly critical and robust component of such a drought monitoring system is a land surface model (LSM). We are currently enhancing the Famine Early Warning Systems Network (FEWS NET) monitoring activities by configuring a custom instance of NASA's Land Information System (LIS) called the FEWS NET Land Data Assimilation System (FLDAS). Using the LIS Noah LSM, in-situ measurements, and remotely sensed data, we focus on the following question: How can Noah be best parameterized to accurately simulate hydroclimate variables associated with crop performance? Parameter value testing and validation is done by comparing modeled soil moisture against fortuitously available in-situ soil moisture observations in the West Africa. Direct testing and application of the FLDAS over African agropastoral locations is subject to some issues: [1] In many regions that are vulnerable to food insecurity ground based measurements of precipitation, evapotranspiration and soil moisture are sparse or non-existent, [2] standard landcover classes (e.g., the University of Maryland 5 km dataset), do not include representations of specific agricultural crops with relevant parameter values, and phenologies representing their growth stages from the planting date and [3] physically based land surface models and remote sensing rain data might still need to be calibrated or bias-corrected for the regions of interest. This research aims to address these issues by focusing on sites in the West African countries of Mali, Niger, and Benin where in-situ rainfall and soil moisture measurements are available from the African Monsoon Multidisciplinary Analysis (AMMA). Preliminary results from model experiments over Southern Malawi, validated with Normalized Difference Vegetation Index (NDVI) and maize yield data, show that the

  18. Genetic population study of Y-chromosome markers in Benin and Ivory Coast ethnic groups.

    Science.gov (United States)

    Fortes-Lima, Cesar; Brucato, Nicolas; Croze, Myriam; Bellis, Gil; Schiavinato, Stephanie; Massougbodji, Achille; Migot-Nabias, Florence; Dugoujon, Jean-Michel

    2015-11-01

    Ninety-six single nucleotide polymorphisms (SNPs) and seventeen short tandem repeat (STRs) were investigated on the Y-chromosome of 288 unrelated healthy individuals from populations in Benin (Bariba, Yoruba, and Fon) and the Ivory Coast (Ahizi and Yacouba). We performed a multidimensional scaling analysis based on FST and RST genetic distances using a large extensive database of sub-Saharan African populations. There is more genetic homogeneity in Ivory Coast populations compared with populations from Benin. Notably, the Beninese Yoruba are significantly differentiated from neighbouring groups, but also from the Yoruba from Nigeria (FST>0.05; P<0.01). The Y-chromosome dataset presented here provides new valuable data to understand the complex genetic diversity and human male demographic events in West Africa.

  19. Insects used for animal feed in West Africa

    Directory of Open Access Journals (Sweden)

    M. Kenis

    2014-10-01

    Full Text Available In West Africa, as in many parts of the world, livestock and fish farming suffer from the increasing cost of feed, especially protein ingredients, which are hardly available for village poultry farming and small-scale fish farming. Insects, which are a natural food source of poultry and fish and are rich in protein and other valuable nutrients, can be used to improve animal diets, a practice which is now strongly promoted by the FAO as a tool for poverty alleviation. This paper reviews practices and research on the use of insects as animal feed in West Africa and the perspectives to further develop the techniques, in particular for smallholder farmers and fish farmers. The most promising insects are flies, especially the house fly (Musca domestica (Diptera Muscidae and the black soldier fly (Hermetia illucens (Diptera Stratiomyiidae, which can be mass reared on-farm for domestic use, in small production units at the community or industrial level. Flies have the advantage over most other insects of developing on freely available waste material and could even contribute to rural sanitation. Termites are traditionally used by smallholder farmers to feed village poultry. While their mass production is problematic, methods to enhance populations on-farm and facilitate collection can be developed. In any case, new methods will need to demonstrate their economic profitability, social acceptability and environmental sustainability

  20. Challenges in meeting biomass energy needs in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Dianka, M. [GAA/RPTES, Dakar (Senegal)

    2001-07-01

    Biomass energy represents conciderable potential for West Africa. However, the traditional methods of tapping into this biomass have not only had grave consequences for the environment, but have only been able to partially resolve the crucial issue of how to sustainably supply households with domestic fuels. Nevertheless, recent progress made in the improvement of technologies enhancing biomass energy provides a glimpse at interesting perspectives fostering the modernisating and better assesment of the biocombustible and biofuel industries. Reflection conducted over these past years by a group of African experts, brought together around the ASG at the instigation of the RPTES Programme and founded on a new approach to forest resource management, illustrates the attention public powers are granting increasingly to biomass energy, which had been relegated to the back burner for so long, to the benefit of more 'conventional' energy sources. Considering the complexity of biomass energy issues, and their direct links to poverty, it is evident that isolated actions will never succeed in solving the problems currently faced. Thus it is essential to promote regional collaboration and partnerships for more effective actions and to capitalise on experiences, with the aim of ensuring sustainable development for the continent of Africa. Today, given the economic potential of more than US$6 billion generated by African forests, this implies the introduction of sustainable strategies which will result in increasing incomes and improving welfare in general. West Africa, masthead of the continent, will certainly not be an isolated case. Consequently, vigorous action supporting the sustainable management of natural resources as part of poverty alleviation programmes should be undertaken post-haste, in compliance with the Abuja Treaty establishing the African Economic Community. (au)

  1. Mapping the potential of cross-border cooperation in West Africa

    DEFF Research Database (Denmark)

    Walther, Olivier; Vollmer, Sebastian

    2015-01-01

    Mapping the socio-economic potential of border regions can provide great insights as to where cross-border co-operation could be intensified in West Africa.......Mapping the socio-economic potential of border regions can provide great insights as to where cross-border co-operation could be intensified in West Africa....

  2. Disease patterns and causes of death of hospitalized HIV-positive adults in West Africa

    DEFF Research Database (Denmark)

    Lewden, Charlotte; Drabo, Youssoufou J; Zannou, Djimon M;

    2014-01-01

    OBJECTIVE: We aimed to describe the morbidity and mortality patterns in HIV-positive adults hospitalized in West Africa. METHOD: We conducted a six-month prospective multicentre survey within the IeDEA West Africa collaboration in six adult medical wards of teaching hospitals in Abidjan, Ouagadou...

  3. Increasing Local Procurement By the Mining Industry in West Africa : Road-test version

    OpenAIRE

    World Bank

    2012-01-01

    Regional organizations and national governments are increasingly focusing on enhancing the benefits from mining sector investment. The Africa Union's African Mining Vision 2050 outlines a new resource-based industrialization and development strategy for Africa, based on downstream, upstream, and side stream linkages, and both Economic Community of West African States (ECOWAS) and West Afri...

  4. The Legacy of Christianity in West Africa, with Special Reference to Burkina Faso

    Science.gov (United States)

    Ouedraogo, Philippe

    2010-01-01

    In the following paper, I am going to discuss education and religion and consider the legacy of Christianity in education in West Africa with particular reference to the Evangelical churches in Burkina Faso. The paper will start with a general introduction to West Africa and the place of missionaries' activities in the region. I will then attempt…

  5. Uses, traditional management, perception of variation and preferences in ackee (Blighia sapida K.D. Koenig) fruit traits in Benin: implications for domestication and conservation

    OpenAIRE

    Eyog-Matig Oscar; Sinsin Brice; Ekué Marius RM; Finkeldey Reiner

    2010-01-01

    Abstract Background Blighia sapida is a woody perennial multipurpose fruit tree species native to the Guinean forests of West Africa. The fleshy arils of the ripened fruits are edible. Seeds and capsules of the fruits are used for soap-making and all parts of the tree have medicinal properties. Although so far overlooked by researchers in the region, the tree is highly valued by farmers and is an important component of traditional agroforestry systems in Benin. Fresh arils, dried arils and so...

  6. Obesity and cardio-metabolic risk factors in urban adults of Benin: Relationship with socio-economic status, urbanisation, and lifestyle patterns

    OpenAIRE

    Delisle Hélène; Agueh Victoire; Fayomi Benjamin; Sodjinou Roger

    2008-01-01

    Abstract Background There is a dearth of information on diet-related chronic diseases in West Africa. This cross-sectional study assessed the rate of obesity and other cardiovascular disease (CVD) risk factors in a random sample of 200 urban adults in Benin and explored the associations between these factors and socio-economic status (SES), urbanisation as well as lifestyle patterns. Methods Anthropometric parameters (height, weight and waist circumference), blood pressure, fasting plasma glu...

  7. 77 FR 74265 - In the Matter of the Designation of Movement for Unity and Jihad in West Africa; Also Known as...

    Science.gov (United States)

    2012-12-13

    ... Matter of the Designation of Movement for Unity and Jihad in West Africa; Also Known as Movement for Oneness and Jihad in West Africa; Also Known as Unity Movement for Jihad in West Africa; Also Known as... Movement for Unity and Jihad in West Africa, also known as Movement ] for Oneness and Jihad in West...

  8. The German Contribution to the Military History of South Africa and South-West Africa

    Directory of Open Access Journals (Sweden)

    H.J. Botha

    2012-02-01

    Full Text Available The Republic of South Africa is the spiritual. Cullural, econolll;c and military extension of the Occident on the Southern extremity of Africa.Situated where it is it does not only form an invaluable link between the East and the West, but at the same time it is one of the most important approaches to the Southern part of the African continent. The foundation of the white society at the Cape was laid by representatives from various Western European nations. In the course of time each one of them contributed towards the development of a young, vigorous nation in this vast land under the Southern Cross - a nation which since its birth, has always recognised the guidance of the Almighty God.

  9. Declining incidence of malaria imported into the UK from West Africa

    Directory of Open Access Journals (Sweden)

    Smith Valerie

    2008-11-01

    Full Text Available Abstract Background Two thirds of all falciparum malaria cases reported in the United Kingdom (UK are acquired in West Africa (WA. To ensure recommendations and guidelines for malaria prophylaxis in travellers to West Africa correlate to the risk of infection, a study was undertaken to examine recent trends and predict future patterns of imported malaria acquired by UK residents visiting West Africa and West African visitors to the UK between 1993 and 2006. Methods and Results Using passenger numbers and malaria surveillance reports, the data revealed a 2.3-fold increase in travel to West Africa with a five-fold increase in travelers visiting friends and relatives (VFR. Malaria incidence fell through the study period, the greatest decline noted in VFR with a fall from 196 cases/1,000 person-years to 52 cases/1,000 person-years, 9.8% per year p Discussion The reduction in incidence among all three groups of travellers may be explained by several factors; changing chemoprophylaxis usage and/or increased travel in urban areas where malaria risk has declined over the past decade, or widespread reduction in malaria transmission in West Africa. Conclusion With the reduction in malaria incidence seen in both visitors to and from West Africa, the most rational explanation for these findings is a fall in malaria transmission in West Africa, which may require a change in chemoprophylaxis policy for UK travelers over the next 5–10 years.

  10. Remote sensing needs and capabilities in West Africa

    Institute of Scientific and Technical Information of China (English)

    Edward M.Osei,Jr.

    2004-01-01

    The greatest advantage of remote sensing over conventional measurements lies in the opportunity to carry out detailed spatio-temporal analysis of land and ocean features on a very frequent basis. This paper analyses the contribution of satellite imagery to atmospheric, geophysical and ocean studies and management in West Africa since the early 1980s.The detailed application of data from optical sensors (e.g. Meteosat,NOAA/AVHRR, SPOT,L andsat TM, etc.) for weather prediction, hydrogeological, landuse/cover and cartographic studies has been acknowledged. However, the use of microwave (e.g. SAR) and optical data for ocean monitoring and studies in the sub-region is still very limited. Even though sufficient remote sensing expertise and infrastructure is perceived in the region, no clearly defined networking or database exists.

  11. Atlantic forcing of persistent drought in West Africa.

    Science.gov (United States)

    Shanahan, T M; Overpeck, J T; Anchukaitis, K J; Beck, J W; Cole, J E; Dettman, D L; Peck, J A; Scholz, C A; King, J W

    2009-04-17

    Although persistent drought in West Africa is well documented from the instrumental record and has been primarily attributed to changing Atlantic sea surface temperatures, little is known about the length, severity, and origin of drought before the 20th century. We combined geomorphic, isotopic, and geochemical evidence from the sediments of Lake Bosumtwi, Ghana, to reconstruct natural variability in the African monsoon over the past three millennia. We find that intervals of severe drought lasting for periods ranging from decades to centuries are characteristic of the monsoon and are linked to natural variations in Atlantic temperatures. Thus the severe drought of recent decades is not anomalous in the context of the past three millennia, indicating that the monsoon is capable of longer and more severe future droughts.

  12. Ebola in West Africa:an international medical emergency

    Institute of Scientific and Technical Information of China (English)

    Yasir; Waheed

    2014-01-01

    West Africa is facing the worst Ebola outbreak with 3685 cases and 1841 deaths reported from Liberia,Cuinea,Senegal,Sierra Leona and Nigeria.There is no vaccine or direct treatment available to treat the patients with Ebola.World Health Organization(WHO) has approved the use of experimental drugs for Ebola patients.Health workers are at high risk.The governments and WHO are responsible to provide necessary protective equipment to health workers dealing with Ebola.There is a strong need to identify the invisible chains of virus transmission.World Bank pledges $200 million to fight against Ebola,while WHO said $430 million are needed to control the Ebola outbreak.Ebola can be contained by early detection and isolation of case,contact tracing,monitoring of contacts and adaptation of rigorous procedures for virus control.

  13. Ebola in West Africa:an international medical emergency

    Institute of Scientific and Technical Information of China (English)

    Yasir Waheed

    2014-01-01

    West Africa is facing the worst Ebola outbreak with 3 685 cases and 1 841 deaths reported from Liberia, Guinea, Senegal, Sierra Leona and Nigeria. There is no vaccine or direct treatment available to treat the patients with Ebola. World Health Organization (WHO) has approved the use of experimental drugs for Ebola patients. Health workers are at high risk. The governments and WHO are responsible to provide necessary protective equipment to health workers dealing with Ebola. There is a strong need to identify the invisible chains of virus transmission. World Bank pledges$200 million to fight against Ebola, while WHO said$430 million are needed to control the Ebola outbreak. Ebola can be contained by early detection and isolation of case, contact tracing, monitoring of contacts and adaptation of rigorous procedures for virus control.

  14. Determinants of Commitment to Agricultural Cooperatives: Cashew Nuts Farmers in Benin

    OpenAIRE

    Mensah, Edouard R.; Karantininis, Kostas; Adegbidi, Anselme; Okello, Julius Juma

    2012-01-01

    Forming and using cooperatives as marketing channel is usually advised to African smallholder farmers for overcoming the constraint of market access. However, limited evidence of cooperative behavior in marketing has been observed. In this paper, we estimate a two-stage model of commitment to cooperatives by cashew nut farmers in Benin, West Africa. In the first stage, we use data on 109 non-members and 168 members and estimate a binary Logit model of farmer’s discrete choice with respect to ...

  15. WASCAL - West African Science Service Center on Climate Change and Adapted Land Use Regional Climate Simulations and Land-Atmosphere Simulations for West Africa at DKRZ and elsewhere

    Science.gov (United States)

    Hamann, Ilse; Arnault, Joel; Bliefernicht, Jan; Klein, Cornelia; Heinzeller, Dominikus; Kunstmann, Harald

    2014-05-01

    Changing climate and hydro-meteorological boundary conditions are among the most severe challenges to Africa in the 21st century. In particular West Africa faces an urgent need to develop effective adaptation and mitigation strategies to cope with negative impacts on humans and environment due to climate change, increased hydro-meteorological variability and land use changes. To help meet these challenges, the German Federal Ministry of Education and Research (BMBF) started an initiative with institutions in Germany and West African countries to establish together a West African Science Service Center on Climate Change and Adapted Land Use (WASCAL). This activity is accompanied by an establishment of trans-boundary observation networks, an interdisciplinary core research program and graduate research programs on climate change and related issues for strengthening the analytical capabilities of the Science Service Center. A key research activity of the WASCAL Competence Center is the provision of regional climate simulations in a fine spatio-temporal resolution for the core research sites of WASCAL for the present and the near future. The climate information is needed for subsequent local climate impact studies in agriculture, water resources and further socio-economic sectors. The simulation experiments are performed using regional climate models such as COSMO-CLM, RegCM and WRF and statistical techniques for a further refinement of the projections. The core research sites of WASCAL are located in the Sudanian Savannah belt in Northern Ghana, Southern Burkina Faso and Northern Benin. The climate in this region is semi-arid with six rainy months. Due to the strong population growth in West Africa, many areas of the Sudanian Savannah have been already converted to farmland since the majority of the people are living directly or indirectly from the income produced in agriculture. The simulation experiments of the Competence Center and the Core Research Program are

  16. Analysing MODIS Phenometrics Quality on Cropped Land in West Africa

    Science.gov (United States)

    Vintrou, Elodie; Begue, Agnes; Baron, Christian; Lo Seen, Danny; Alexandre, Saad; Traore, Seydou

    2012-04-01

    Crop phenology is essential information when evaluating crop production in the food insecure regions of West Africa. The only currently available global product that includes phenological variables is the MODIS Land Cover Dynamics Yearly (MCD12Q2) product. This product is produced each year at 500 m spatial resolution, from the 8-day vegetation index EVI (Enhanced Vegetation Index) calculated from the NBAR reflectance (Nadir Bidirectional Reflectance Distribution Function - Adjusted Reflectance). In order to analyze the information content of MODIS MCD12Q2 product, the phenological variables were extracted for areas previously identified as cropped on eight specific sites in Mali and compared to rainfall data and expert knowledge on Malian agriculture. MODIS MCD12Q2 data analysis showed that only 70% of the cropped pixels in Southern Mali had a complete phenology information on the whole vegetation cycle (four phenometrics values), and that a large part of the pixels displayed unrealistic late Start-Of-Season (SOS) values. A close analysis of the original EVI data indicated that these inconsistent SOS values were due to missing EVI data during the vegetation development phase (due to the presence of cloud cover) conducting to a false detection of SOS. We then proposed a simple way to correct the SOS values. In Africa, food security systems could benefit from such a phenology product, by utilizing its spatially continuous information in agro-meteorological modeling, and thus improving agricultural production estimation.

  17. Desertification, refugees and regional conflict in west Africa.

    Science.gov (United States)

    Nnoli, O

    1990-06-01

    This article documents the potential for inter-state conflict in the migration of hundreds of thousands of famine refugees across international borders in West Africa. Nigeria and Ghana, for example, have to deal not only with the effects of land degradation in their northern territories but also with the influx of famine victims from Mali, Niger, Chad and Burkino Faso. These migrations put an enormous extra burden on the fragile and already overstretched social and economic infrastructures of the host countries. The construction of dams for irrigation and electricity generation in international river basins, is another cause of inter-state conflict related to land degradation. The capacity of West African states to find peaceful solutions to these problems is being undermined by the increasing impoverishment and marginalisation of their populations. A self-serving neo-colonialist governing elite is caught in the economic stranglehold of the advanced capitalist nations. While there is thus no short term solution to the problem of land degradation, immediate steps should at least be taken to give legal protection to those who are forced to cross international borders because of drought and famine. PMID:20958699

  18. An interventional model to develop health professionals in West Africa.

    Science.gov (United States)

    Sanou, Anselme Simeon; Awoyale, Florence Adeola; Diallo, Abdoulaye

    2014-01-01

    The health sector is characterized by a human resource base lacking in numbers, specialized skills, and management skills. West African Health Organization (WAHO) recognizes the need within the West Africa sub-region for bilingual professionals who are skilled in public health, management, leadership, and information technology to build human capacity in public health and developed the Young Professionals Internship Program (YPIP). Our study explores the evolution of the programme. YPIP program has successfully carried out its original aims and objectives to equip young professionals with basic principles of public health, management, and leadership, acquire competence in a second official language (French, English, and Portuguese), information and communication technology. Contributing factors towards this successful evaluation included positive ratings and commentary from previous interns about the relevance, usefulness, and quality of the programme, encouraging feedback from WAHO management, trainers, administrators, and intern employers on the impact of the YPIP program on young professionals, supporting evidence that demonstrates increased knowledge in professional skills and language competency.

  19. Holocene mangrove swamps of West Africa sedimentology and soils

    Science.gov (United States)

    Marius, C.; Lucas, J.

    The mangrove swamps of West African Coast belong to the Atlantic type which is characterized by a small number of species. They colonize tidal environments which are dissected by numerous meandering tidal channels and are presently subject to a low rate of sediment accumulation. The mangrove vegetation exhibits a characteristic zonation pattern that basically reflects the adaptation of the various species to saline conditions. The typical zonation sequence is: Rhizophora racemosa (or Rh. mangle), Rh. mangle + Avicennia africana, Avicennia, flooded tanne, barren tanne, herbaceous tanne. The tannes are generated by aridic climatic conditions, heavy soil and water salt content, and are, in a way a peculiar feature of mangrove swamps in West Africa. The sediment colonized by the mangroves is relatively homogenous. Mineralogically, they are dominated by quartz and clay to which are associated halite, pyrite and jarosite. The clay suite is mainly composed of smectite and kaolinite. Smectite is predominant in the inlet areas and is replaced inland by kaolinite. Chemically, the sediments contain very low amounts of Ca, bases and trace elements. The mangrove swamp floodwaters have a chemical composition similar to that of seawater. It is dominated by sodium and chloride. Morphologically, the ripening of the soils appears with a chestnut mash colour horizon and buttery consistency in relation with the decomposition of fibrous roots of Rhizophora and also with pale yellow jarosite mottles in the top horizons of the tanne profiles due to the oxidation of pyrine. The two main properties of the mangrove soils of West Africa are acidity and salinity; the first is related to the high content of sulphur and the second to the sea influence. The acidity has to be connected mainly to the Rhizophora vegetation whose the root system is a real trap for catching the pyrites resulting from the reduction of the sulphates of sea water by the sulphate reducing bacteria, in a reduced

  20. Partnership research on nutrition transition and chronic diseases in West Africa – trends, outcomes and impacts

    Directory of Open Access Journals (Sweden)

    Fayomi Benjamin

    2011-11-01

    Full Text Available Abstract Background Nutrition-related chronic diseases (NRCD are rising quickly in developing countries, and the nutrition transition is a major contributor. Low-income countries have not been spared. Health issues related to nutritional deficiencies also persist, creating a double burden of malnutrition (DBM. There is still a major shortage of data on NRCD and DBM in Sub-Saharan Africa. A research program has been designed and conducted in partnership with West African institutions since 2003 to determine how the nutrition transition relates to NRCD and the DBM in order to support prevention efforts. Methods In Benin, cross-sectional studies among apparently healthy adults (n=540 from urban, semi-urban and rural areas have examined cardiometabolic risk (hypertension, obesity, dyslipidemia, insulin resistance in relation to diet and lifestyle, also factoring in socio-economic status (SES. Those studies were followed by a longitudinal study on how risk evolves, opening the way for mutual aid groups to develop a prevention strategy within an action research framework. In Burkina Faso, a cross-sectional study on the nutritional status and dietary patterns of urban school-age children (n=650 represented the initial stages of an action research project to prevent DBM in schools. A cross-sectional study among adults (n=330 from the capital of Burkina Faso explored the coexistence, within these individuals, of cardiometabolic risk factors and nutritional deficiencies (anemia, vitamin A deficiency, chronic energy deficiency, as they relate to diet, lifestyle and SES. Results The studies have shown that the prevalence of NRCD is high among the poor, thereby exacerbating social inequalities. The hypothesis of a positive socio-economic (and rural–urban gradient was confirmed only for obesity, whereas the prevalence of hypertension, insulin resistance and dyslipidemia did not prove to be higher among affluent city dwellers. Women were particularly

  1. Molecular Surveillance Identifies Multiple Transmissions of Typhoid in West Africa

    Science.gov (United States)

    Wong, Vanessa K.; Holt, Kathryn E.; Okoro, Chinyere; Baker, Stephen; Pickard, Derek J.; Marks, Florian; Page, Andrew J.; Olanipekun, Grace; Munir, Huda; Alter, Roxanne; Fey, Paul D.; Feasey, Nicholas A.; Weill, Francois-Xavier; Le Hello, Simon; Hart, Peter J.; Kariuki, Samuel; Breiman, Robert F.; Gordon, Melita A.; Heyderman, Robert S.; Jacobs, Jan; Lunguya, Octavie; Msefula, Chisomo; MacLennan, Calman A.; Keddy, Karen H.; Smith, Anthony M.; Onsare, Robert S.; De Pinna, Elizabeth; Nair, Satheesh; Amos, Ben; Dougan, Gordon; Obaro, Stephen

    2016-01-01

    Background The burden of typhoid in sub-Saharan African (SSA) countries has been difficult to estimate, in part, due to suboptimal laboratory diagnostics. However, surveillance blood cultures at two sites in Nigeria have identified typhoid associated with Salmonella enterica serovar Typhi (S. Typhi) as an important cause of bacteremia in children. Methods A total of 128 S. Typhi isolates from these studies in Nigeria were whole-genome sequenced, and the resulting data was used to place these Nigerian isolates into a worldwide context based on their phylogeny and carriage of molecular determinants of antibiotic resistance. Results Several distinct S. Typhi genotypes were identified in Nigeria that were related to other clusters of S. Typhi isolates from north, west and central regions of Africa. The rapidly expanding S. Typhi clade 4.3.1 (H58) previously associated with multiple antimicrobial resistances in Asia and in east, central and southern Africa, was not detected in this study. However, antimicrobial resistance was common amongst the Nigerian isolates and was associated with several plasmids, including the IncHI1 plasmid commonly associated with S. Typhi. Conclusions These data indicate that typhoid in Nigeria was established through multiple independent introductions into the country, with evidence of regional spread. MDR typhoid appears to be evolving independently of the haplotype H58 found in other typhoid endemic countries. This study highlights an urgent need for routine surveillance to monitor the epidemiology of typhoid and evolution of antimicrobial resistance within the bacterial population as a means to facilitate public health interventions to reduce the substantial morbidity and mortality of typhoid. PMID:27657909

  2. Ebola outbreak in West Africa: a neglected tropical disease

    Institute of Scientific and Technical Information of China (English)

    Alcides; Troncoso

    2015-01-01

    Neglected tropical diseases(NTDs) are remediable injustices of our times. Poverty is the starting point, and the ultimate outcome, of NTD. Ebola is just one of many NTDs that badly need attention. Ebola exacerbates West Africa’s poverty crisis. The virus spreading in Guinea,Liberia and Sierra Leone has led to food shortages and neglect of other devastating tropical illnesses. A health crisis that was ignored for months until it was out of control is now beginning to get the attention required, if not the resources. So far, the world′s nations have contributed far less than the $ 1 billion. The U.N. estimates would need to control the epidemic before it becomes endemic. Past outbreaks of Ebola have flared up in remote, forested communities, disconnected from much of the outside world. But the outbreak in West Africa has not slowed yet, and it worsens there the chances of it spreading to other countries. Ebola draws attention to NTD. Ebola is not only a health emergency, but also it′s a poverty crisis.The current Global Ebola crisis presents a multitude of challenges in terms of our capacity to respond; the future is even less predictable. Ebola outbreak represents inequity in health as the occurrence of health differences considered unnecessary, avoidable, unfair, and unjust, thus adding a moral and ethical dimension to health inequalities. Health equity does not refer only to the fairness in the distribution of health or the provision of health care; rather, it is linked with the larger issues of fairness and justice in social arrangements.

  3. Child fostering in West Africa: New perspectives on theory and practices

    NARCIS (Netherlands)

    Alber, E.; Martin, J.; Notermans, C.D.

    2013-01-01

    Introduction / Erdmute Alber, Jeannett Martin and Catrien Notermans -- A framework for the analysis of parent roles / Esther Goody -- Adoption, fosterage and marriage / Suzanne Lallemand -- The transfer of belonging: theories on child fostering in West Africa reviewed / Erdmute Alber -- Experiencing

  4. Population dynamics of freshwater oyster Etheria elliptica (Bivalvia: Etheriidae in the Pendjari River (Benin-Western Africa

    Directory of Open Access Journals (Sweden)

    Akélé G.D.

    2015-01-01

    Full Text Available Etheria elliptica (Bivalvia: Etheriidae is the only freshwater oyster occurring in Africa. The current study provides the first data on the population structure, growth, age, mortality and exploitation status of this species in the Pendjari River. E. elliptica length-frequency data were collected monthly from January to December 2009 and analyzed with FiSAT software. Population parameters including the asymptotic length (L∞ and growth coefficient (K were assessed to evaluate the stock status. The recruitment pattern was modeled with a FiSAT routine. The asymptotic length (L∞ was 14.75 cm, while the growth coefficient (K was 0.38 year-1. The growth performance index (ø′ reached 1.92. Specimens of Etheria elliptica reached a mean size of 4.66 cm and 6.41 cm at the end of one year and 1.5 years, respectively. We estimated total mortality (Z, natural mortality (M and fishing mortality (F to be 2.90 year-1, 1.16 year-1 and 1.74 year-1, respectively. The recruitment pattern was continuous over the year with one major peak event during the rainy season (July. The exploitation rate (E = 0.60 revealed that the freshwater oyster was probably facing overexploitation due to lack of a minimum limit size and also due to an increase in the harvesting effort. Therefore, efficient management methods were urgently required to conserve the species. The return of empty shells into the water to increase the recruitment surface, rotation planning among harvesting sites and the imposition of a minimum limit size were recommendations made in order to ensure the sustainable exploitation of wild stocks.

  5. The indigenous Somba cattle of the hilly Atacora region in North-West Benin: threats and opportunities for its sustainable use.

    Science.gov (United States)

    Dossa, Luc Hippolyte; Vanvanhossou, Fridaïus Ulrich Sèyi

    2016-02-01

    The objective of this study was to characterize the declining Somba cattle population in its production system context. Two-hundred-twenty-four (224) cattle farm-households were surveyed in the Boukombe district, the natural habitat of the breed in North-West Benin. Information on their socioeconomic characteristics and on their herd management practices were recorded using a semi-structured questionnaire. In addition, 15 body measurements were recorded from 102 adult cattle. Three types of breeders were distinguished: the owners-herders (54.0 %); the absentee owners (40.2 %) and the professional herders (5.8 %). The average cattle herd sizes were 4.7 ± 3.70 and 58.6 ± 22.83 heads for owner-managed and entrusted herds, respectively. Offtakes were more associated with sociocultural purposes (75.5 %) than market. While crop farming was the main occupation and income source of their owners, the Somba cattle were used for ploughing during the rainy season. In contrast to the widely accepted belief that this indigenous genetic resource is mainly threatened by crossbreeding and/or replacement, our findings suggest high mortalities due to diseases, feed and water shortages and poor reproduction management as the main causes of the decline of this cattle population. Somba cattle generally have short horns and a small body size. However, bulls have significantly (P ≤ 0.05) longer horns (21.2 ± 16.44 cm against 13.9 ± 7.21 cm), higher height at withers (99.7 ± 6.97 cm against 95.9 ± 5.76 cm) and body length (149.7 ± 12.87 cm against 146.8 ± 11.01 cm) than cows. All surveyed farmers expressed their willingness and readiness to participate in and contribute materially or financially to any program towards a sustainable use and preservation of this breed which they perceived as hardy and embedded in their culture. We therefore argue that strategies for its sustainable use and conservation should consist of simultaneously

  6. Farmer-Researcher Networks in West African Organic Value Chains. Economic and Sociological Challenges

    OpenAIRE

    Nicolay, Gian L.

    2014-01-01

    Farming in tropical Africa is getting more and more complex. Land shortages often lead to soil fertility decline, as the usual fallow can’t be practiced anymore. Organic farmers have to compete additionally with subsidized synthetic fertilizer programs, cost-rising GMO competition and policy preferences for conventional and non-organic practices. The EuropeAid funded Syprobio project in West Africa (Mali, Burkina Faso and Benin) involves organic farmers, researchers and technicians from farm ...

  7. Power sector restructuring in West Africa. The issues

    International Nuclear Information System (INIS)

    At independence, most countries in the West Africa sub-region adopted a development strategy which was spearheaded by the public sector. The aims at presenting discussions on some of the major issues on initiating the reform process and issues associated with the transition period. Section 2 looks at the energy resources for power development in the region and section 3 discusses some unsustainable trends in the sector. Section 4 presents the issues and discusses them, and finally, section 5 presents the conclusion and some policy implications. The discussions in the paper stress the point that reforming the power sector in the countries in the region is not simply a question of implementing consultants' recommendations, but rather a process that must be thought through, and also involves bringing all the shareholders along and putting the regulatory system and institution in place to ensure acceptability and implementatibility of the proposed changes. Governments in the region have a responsibility to build the capacity necessary to initiate and manage the reform process in the power sector, and understanding the issues involved will help to adopt the right approach to reforming the sector. (ARW) 11 refs

  8. An empirical analysis of the Ebola outbreak in West Africa

    CERN Document Server

    Khaleque, Abdul

    2016-01-01

    The data for the Ebola outbreak that occurred in 2014-2016 in three countries of West Africa are analysed within a common framework. The analysis is made using the results of an agent based Susceptible-Infected-Removed (SIR) model on a Euclidean network, where nodes at a distance $l$ are connected with probability $P(l) \\propto l^{-\\delta }$ in addition to nearest neighbors. The cumulative density of infected population here has the form $R(t) = \\frac{a\\exp(t/T)}{1+c\\exp(t/T)}$, where the parameters depend on $\\delta$ and the infection probability $q$. This form is seen to fit well with the data. Using the best fitting parameters, the time at which the peak is reached is estimated and is shown to be consistent with the data. We also show that in the Euclidean model, one can choose $\\delta$ and $q$ values which reproduce the data for the three countries qualitatively. These choices are correlated with population density, control schemes and other factors.

  9. Data Integration for Climate Vulnerability Mapping in West Africa

    Directory of Open Access Journals (Sweden)

    Alex de Sherbinin

    2015-11-01

    Full Text Available Vulnerability mapping reveals areas that are likely to be at greater risk of climate-related disasters in the future. Through integration of climate, biophysical, and socioeconomic data in an overall vulnerability framework, so-called “hotspots” of vulnerability can be identified. These maps can be used as an aid to targeting adaptation and disaster risk management interventions. This paper reviews vulnerability mapping efforts in West Africa conducted under the USAID-funded African and Latin American Resilience to Climate Change (ARCC project. The focus is on the integration of remotely sensed and socioeconomic data. Data inputs included a range of sensor data (e.g., MODIS NDVI, Landsat, SRTM elevation, DMSP-OLS night-time lights as well as high-resolution poverty, conflict, and infrastructure data. Two basic methods were used, one in which each layer was transformed into standardized indicators in an additive approach, and another in which remote sensing data were used to contextualize the results of composite indicators. We assess the benefits and challenges of data integration, and the lessons learned from these mapping exercises.

  10. Multi-level governance and adaptive capacity in West Africa

    Directory of Open Access Journals (Sweden)

    Maria Brockhaus

    2012-08-01

    Full Text Available In most regions in West Africa, livelihoods depend heavily on forest ecosystem goods and services, often in interplay with agricultural and livestock production systems. Numerous drivers of change are creating a range of fundamental economic, ecological, social and political challenges for the governance of forest commons. Climate change and its impacts on countries’ and regions’ development add a new dimension to an already challenging situation. Governance systems are challenged to set a frame for formulating, financing and implementing adaptation strategies at multiple layers, often in a context of ongoing institutional changes such as decentralisation. A deeper understanding of actors, institutions and networks is needed to overcome barriers in socio-ecological systems to adaptation and enable or enhance adaptive capacity. In this paper, we explore the relationship between governance and adaptive capacity, and characterise and assess the effects of a set of variables and indicators related to two core variables: Institutional flexibility, and individual and organisational understandings and perceptions. We present a comparative analysis with multiple methods based on a number of case studies undertaken at different levels in Burkina Faso and Mali. One of the key findings indicates the importance and influence of discourses and narratives, and how they affect adaptive capacity at different levels. Revealing the ideological character of discourses can help to enable adaptive capacity, as it would break the influence of the actors that employ these narratives to pursuit their own interests.

  11. Benin: country profile.

    Science.gov (United States)

    Gabriel, A

    1987-10-01

    Since 1972, Benin has had an official Marxist-Leninist ideology; however, centralized state control contributed to economic stagnation and a search for capital investment. A special section of the World Bank is advising the Government of Benin on public sector reform and privatization, and an agreement with the International Monetary Fund seems likely. At present, 65% of Benin's labor force is engaged in subsistence agriculture, most of which is collectivized, and the gross national product per capita is US$260. The main cash crops are seed cotton and palm oil kernels used in soap and margarine. While women occupy key trade positions in the south of Benin, they are very oppressed in the north. Benin has a population of 4 million. The infant mortality rate is 115/1000 lives births and life expectancy is 43 years. Only 21% of the population has access to clean water. 40% of men, compared to just 17% of women, are literate.

  12. Assessing climate change impacts on sorghum and millet yields in the Sudanian and Sahelian savannas of West Africa

    Science.gov (United States)

    Sultan, B.; Roudier, P.; Quirion, P.; Alhassane, A.; Muller, B.; Dingkuhn, M.; Ciais, P.; Guimberteau, M.; Traore, S.; Baron, C.

    2013-03-01

    Sub-Saharan West Africa is a vulnerable region where a better quantification and understanding of the impact of climate change on crop yields is urgently needed. Here, we have applied the process-based crop model SARRA-H calibrated and validated over multi-year field trials and surveys at eight contrasting sites in terms of climate and agricultural practices in Senegal, Mali, Burkina Faso and Niger. The model gives a reasonable correlation with observed yields of sorghum and millet under a range of cultivars and traditional crop management practices. We applied the model to more than 7000 simulations of yields of sorghum and millet for 35 stations across West Africa and under very different future climate conditions. We took into account 35 possible climate scenarios by combining precipitation anomalies from -20% to 20% and temperature anomalies from +0 to +6 °C. We found that most of the 35 scenarios (31/35) showed a negative impact on yields, up to -41% for +6 °C/ - 20% rainfall. Moreover, the potential future climate impacts on yields are very different from those recorded in the recent past. This is because of the increasingly adverse role of higher temperatures in reducing crop yields, irrespective of rainfall changes. When warming exceeds +2 °C, negative impacts caused by temperature rise cannot be counteracted by any rainfall change. The probability of a yield reduction appears to be greater in the Sudanian region (southern Senegal, Mali, Burkina Faso, northern Togo and Benin), because of an exacerbated sensitivity to temperature changes compared to the Sahelian region (Niger, Mali, northern parts of Senegal and Burkina Faso), where crop yields are more sensitive to rainfall change. Finally, our simulations show that the photoperiod-sensitive traditional cultivars of millet and sorghum used by local farmers for centuries seem more resilient to future climate conditions than modern cultivars bred for their high yield potential (-28% versus -40% for

  13. Can hospital audit teams identify case management problems, analyse their causes, identify and implement improvements? A cross-sectional process evaluation of obstetric near-miss case reviews in Benin.

    OpenAIRE

    Borchert Matthias; Goufodji Sourou; Alihonou Eusèbe; Delvaux Thérèse; Saizonou Jacques; Kanhonou Lydie; Filippi Véronique

    2012-01-01

    Abstract Background Obstetric near-miss case reviews are being promoted as a quality assurance intervention suitable for hospitals in low income countries. We introduced such reviews in five district, regional and national hospitals in Benin, West Africa. In a cross-sectional study we analysed the extent to which the hospital audit teams were able to identify case management problems (CMPs), analyse their causes, agree on solutions and put these solutions into practice. Methods We analysed ca...

  14. Interaction Of Mesoscale Convective Systems With The Land - Sea Breezes Along The Guinea Coast Of West Africa

    Science.gov (United States)

    Coulibaly, A.; Omotosho, B. J.; Sylla, M. B.; Fink, A. H.

    2015-12-01

    1-3 hourly METARS/SYNOP observation data of wind (speed and direction), air temperature over land, covering the period 1983-2012, were used in order to characterize land-sea breezes (LSB) over five coastline stations (Abidjan, Accra, Lomé, Cotonou and Ikeja-Lagos) in the Guinean Coast, West Africa. In additional to this, 8 years (2003-2010) sea surface temperature (SST) data from adjacent Atlantic Ocean and monthly METARS/SYNOP observation data of precipitation (1983-2012) were also used. Based on wind speed and direction, the wind roses of all months over all stations have been plotted. These wind roses reveal that, globally, the northerly winds occurred rarely for the months of February, March, and April at Cotonou (Benin Republic).This is seen for other stations (Lomé and Accra). The night/morning time northerly winds appear at all stations, except Accra where there is no northerly wind or is very weak. According to the stations basis, the period of that night/morning northerly winds varies, except in summer period (July - September), where the normal s/w monsoon winds can weaken override at all stations. Set criteria based on the diurnal reversal of wind direction, and the thermal gradient necessary to drive the wind circulation, was used to identify land-sea breeze days. On station-wide basis, sea-breezes occur, at least all period of year, but less frequent in the summer months, where the minimum value of monthly mean temperature gradient is observed for selected stations.

  15. Connecting Food Staples and Input Markets in West Africa

    OpenAIRE

    Maur, Jean-Christophe; Shepherd, Ben

    2015-01-01

    The report Africa Can Help Feed Africa (World Bank 2012) showed that increasing food staples1 supply can be met by better connecting African markets to each other. That report called for a stronger focus on removing trade barriers and building on the forces of regional integration. This report builds on the lessons of Africa Can Help Feed Africa by looking into the specific circum¬stances ...

  16. Modelling the impacts of deforestation on monsoon rainfall in West Africa

    International Nuclear Information System (INIS)

    The study found that deforestation causes more monsoon moisture to be retained in the mid-troposphere, thereby reducing the northward transport of moisture needed for rainfall over West Africa. Hence, deforestation has dynamical impacts on the West African monsoon and rainfall.

  17. Monitoring water stock variations by gravimetry in Benin

    Science.gov (United States)

    Seguis, L.; Galle, S.; Descloitres, M.; Laurent, J.-P.; Grippa, M.; Pfeffer, J.; Luck, B.; Genthon, P.; Hinderer, J.

    2009-04-01

    In Central Benin (wet Soudanian climate), in the frame of the AMMA (African Monsoon Multidisciplinary Analysis) program, an hydrological observatory has been set up since 2000. It is based on embedded catchments from a few to twelve thousand squared kilometers. At the local scale, 3 hillslopes with contrasted vegetation covers were selected in 2005 to study the water redistribution processes. With the aim to close the water budget at this scale, the instrumentation device was composed of instruments which monitored the 1st meter of the vadoze zone (succion, humidetric and temperature probes), the groundwater (piezometers screened at different depths) and a flux station to control evapotranspiration. Seasonal water storage changes can be monitored at this local scale but determination of the water budget at catchment scale is still difficult and needs modelling. A promising method seems to be the monitoring of the gravimetric variations. The GHYRAF French project (Gravity and Hydrology in Africa) started in 2008. It is devoted to the water storage variation assessment in sub-saharian Africa. In this aim it carries detailed comparison between models and multidisciplinary observations (ground and satellite gravity, geodesy, hydrology, meteorology). To perform this intercomparison, the main surface gravity experiment consists in periodic absolute gravity measurements at specific points along a north-south monsoonal gradient of rainfall in West Africa (Tamanrasset (20 mm annual rainfall depth) in southern Algeria, Niamey (500 mm) and a Soudanian site in Central Benin (1200 mm). In Benin, three gravity measurements have been already done on the key periods of the water cycle (July 2008 : on-set of the groundwater recharge, September 2008 : highest water table and wettest state in the vadoze zone, January 2009, low water table and dry state in the vadoze zone). We present here the preliminary comparisons of the water storage variation estimations deduced from the

  18. Response of the Water Cycle of West Africa and Atlantic to Radiative Forcing by Saharan Dust

    Science.gov (United States)

    Lau, K. M.; Kim, Kyu-Myong; Sud, Yogesh C.; Walker, Gregory L.

    2010-01-01

    The responses of the atmospheric water cycle and climate of West Africa and the Atlantic to radiative forcing of Saharan dust are studied using the NASA finite volume general circulation model (fvGCM), coupled to a mixed layer ocean. We find evidence in support of the "elevated heat pump" (EHP) mechanism that underlines the responses of the atmospheric water cycle to dust forcing as follow. During the boreal summer, as a result of large-scale atmospheric feed back triggered by absorbing dust aerosols, rainfall and cloudiness are enhanced over the West Africa/Easter Atlantic ITCZ, and suppressed over the West Atlantic and Caribbean. region. Shortwave radiation absorption by dust warms the atmosphere and cools the surface, while long wave has the opposite response. The elevated dust layer warms the air over Nest Africa and the eastern Atlantic. The condensation heating associated with the induced deep convection drives and maintains an anomalous large-scale east-west overturning circulation with rising motion over West Africa/eastern Atlantic, and sinking motion over the Caribbean region. The response also includes a strengthening of the West African monsoon, manifested in northward shift of the West Africa precipitation over land, increased low-level westerlies flow over West Africa at the southern edge of the dust layer, and a near surface energy fluxes, resulting in cooling of the Nest African land and the eastern Atlantic, and a warming in the West Atlantic and Caribbean. The EHP effect is most effective for moderate to highly absorbing dusts, and becomes minimized for reflecting dust with single scattering albedo at 0.95 or higher.

  19. Pheromone Blend Analysis and Cross-Attraction among Populations of Maruca vitrata from Asia and West Africa.

    Science.gov (United States)

    Schläger, Stefanie; Beran, Franziska; Groot, Astrid T; Ulrichs, Christian; Veit, Daniel; Paetz, Christian; Karumuru, Bhanu R M; Srinivasan, Ramasamy; Schreiner, Monika; Mewis, Inga

    2015-12-01

    The legume pod borer, Maruca vitrata, is a pantropical pest on leguminous crops. (E,E)-10,12-Hexadecadienal, (E,E)-10,12-hexadecadienol, and (E)-10-hexadecenal were described previously as sex pheromone components for this nocturnal moth. A blend of these components in a ratio of 100:5:5 attracted males in field trapping experiments in Benin, but not in Taiwan, Thailand, or Vietnam. This finding suggests geographic variation in the pheromone blend between Asian and West African populations of M. vitrata. We, therefore, determined the pheromone compositions of single pheromone glands of females from the three Asian regions and from Benin by gas chromatography-mass spectrometry. Additionally, we compared the responses of males from Taiwan and Benin to calling females and to gland extracts of females from both regions in laboratory no-choice and two-choice assays. Chemical analysis revealed the presence of (E,E)-10,12-hexadecadienal and (E,E)-10,12-hexadecadienol, as well as the absence of (E)-10-hexadecenal in all four populations. The relative amounts of the detected compounds did not vary significantly among the insect populations. The behavioral bioassays showed that Taiwanese and Beninese males were similarly attracted to females from both regions, as well as to their gland extracts. As a result, we did not find geographic variation in the sexual communication system of M. vitrata between West African and Asian insect populations.

  20. Groundwater Exploration for Rural Communities in Ghana, West Africa

    Science.gov (United States)

    McKay, W. A.

    2001-05-01

    Exploration for potable water in developing countries continues to be a major activity, as there are more than one billion people without access to safe drinking water. Exploration for groundwater becomes more critical in regions where groundwater movement and occurrence is controlled by secondary features such as fractures and faults. Drilling success rates in such geological settings are generally very low, but can be improved by integrating geological, hydrogeological, aerial photo interpretation with land-based geophysical technology in the selection of drilling sites. To help alleviate water supply problems in West Africa, the Conrad N. Hilton Foundation and other donors, since 1990, have funded the World Vision Ghana Rural Water Project (GRWP) to drill wells for potable water supplies in the Greater Afram Plains (GAP) of Ghana. During the first two years of the program, drilling success rates using traditional methods ranged from 35 to 80 percent, depending on the area. The average drilling success rate for the program was approximately 50 percent. In an effort to increase the efficiency of drilling operations, the Desert Research Institute evaluated and developed techniques for application to well-siting strategies in the GAP area of Ghana. A critical project element was developing technical capabilities of in-country staff to independently implement the new strategies. Simple cost-benefit relationships were then used to evaluate the economic advantages of developing water resources using advanced siting methods. The application of advanced methods in the GAP area reveal an increase of 10 to 15 percent in the success rate over traditional methods. Aerial photography has been found to be the most useful of the imagery products covering the GAP area. An effective approach to geophysical exploration for groundwater has been the combined use of EM and resistivity methods. Economic analyses showed that the use of advanced methods is cost-effective when success

  1. Observations of OH and HO2 radicals over West Africa

    Directory of Open Access Journals (Sweden)

    D. E. Heard

    2010-03-01

    Full Text Available The hydroxyl radical (OH plays a key role in the oxidation of trace gases in the troposphere. However, observations of OH and the closely related hydroperoxy radical (HO2 have been sparse, especially in the tropics. Based on a low-pressure laser-induced fluorescence technique (FAGE – Fluorescence Assay by Gas Expansion, an instrument has been developed to measure OH and HO2 aboard the Facility for Airborne Atmospheric Measurement (FAAM BAe-146 research aircraft. The instrument is described and the calibration method is discussed. During the African Monsoon Multidisciplinary Analyses (AMMA campaign, observations of OH and HO2 (HOx were made in the boundary layer and free troposphere over West Africa on 13 flights during July and August 2006. Mixing ratios of both OH and HO2 were found to be highly variable but followed a diurnal cycle, with a median HO2/OH ratio of 95. Daytime OH observations were compared with the primary production rate of OH from ozone photolysis in the presence of water vapour. Daytime HO2 observations were generally reproduced by a simple steady-state HOx calculation, where HOx was assumed to be formed from the primary production of OH and lost through HO2 self-reaction. Deviations between the observations and this simple model were found to be grouped into a number of specific cases: (a in the presence of high levels of isoprene in the boundary layer, (b within a biomass burning plume and (c within cloud. In the forested boundary layer, HO2 was underestimated at altitudes below 500 m but overestimated between 500 m and 2 km. In the biomass burning plume, OH and HO2 were both significantly reduced compared to calculations. HO2 was sampled in and around cloud, with significant short-lived reductions of HO2 observed. HO2 observations were better reproduced by a steady state calculation with heterogeneous loss of HO2 onto cloud droplets included. Up to 9 pptv of HO2 was observed at night, increasing early in the morning

  2. A Multivariate Analysis of Freshwater Variability over West Africa

    Science.gov (United States)

    Andam-Akorful, S. A.; He, X.; Ferreira, V. G.; Quaye-Ballard, J. A.

    2015-12-01

    As one of the most vulnerable regions to climate change, West Africa (WA) has since the 1970s suffered sustained reduction in rainfall amounts, leading to droughts and associated negative impacts on its water resources. Although rainfall rates have been reported to have experienced a degree of recovery, dry conditions persist. Additionally, the region faces perennial flooding, thus resulting in a highly variable hydrologic regime due to the extreme climate conditions. This therefore necessitates routine monitoring of the WA's freshwater reserves and its response to climate variations at the short and long term scales to aid sustainable use and management. However, this monitoring is hampered by data deficiency issues within the region. Consequently, dynamics leading to changes in water availability over the region are not completely understood. In this work, the recent flux and state of freshwater availability over WA from 1979 to 2013 is assessed by investigating the coupled variability of GRACE-derived terrestrial water storage (TWS) and its changes (TWSC) estimates with rainfall, evapotranspiration, and land surface air temperature (LSAT), as well as, major global and regional teleconnection indices using complex principal component analysis and wavelet transforms. Since GRACE covers a relatively short period, and thereby present challenges for long to medium term analyses, Artificial Neural Network (ANN) is employed to extend the GRACE series to 1979. The results from the ANN proved to be robust upon evaluation; spatially-averaged series for major basins and sub-climatic zones, as well as, the whole of WA presented RMSE, Nash-Sutcliffe efficient, and coefficient of determination (R2) of 11.83 mm, 0.76 and 0.89 respectively. Overall, the results obtained from this study indicate that, sustained increase in water flux, in terms of TWSC, contributed to a resurgence in freshwater reserves in the 21st century over WA from the low levels in the late 20th century

  3. Modeling the impact of changes in Atlantic sea surface temperature on the climate of West Africa

    Science.gov (United States)

    Adeniyi, Mojisola O.

    2016-08-01

    This study assesses the impacts of warming/cooling of the Atlantic sea surface temperature (SST) on the climate of West Africa using Version 4.4 of Regional Climate Model (RegCM4.4) of International Center for Theoretical Physics, Trieste, Italy. The 1-2 K cooling and warming of the Atlantic SST both result in tripole temperature and precipitation change structure, having a northwest-southeast orientation over West Africa. Findings reveal that the responses of precipitation and temperature to the Atlantic SST cooling are opposite to those for the Atlantic SST warming and these responses intensify with increased warming/cooling of the Atlantic SST. The structure of the change in climate is attributed to the response of atmospheric/soil moisture gradient and orientation of orography in West Africa.

  4. What factors might have led to the emergence of Ebola in West Africa?

    Directory of Open Access Journals (Sweden)

    Kathleen A Alexander

    Full Text Available An Ebola outbreak of unprecedented scope emerged in West Africa in December 2013 and presently continues unabated in the countries of Guinea, Sierra Leone, and Liberia. Ebola is not new to Africa, and outbreaks have been confirmed as far back as 1976. The current West African Ebola outbreak is the largest ever recorded and differs dramatically from prior outbreaks in its duration, number of people affected, and geographic extent. The emergence of this deadly disease in West Africa invites many questions, foremost among these: why now, and why in West Africa? Here, we review the sociological, ecological, and environmental drivers that might have influenced the emergence of Ebola in this region of Africa and its spread throughout the region. Containment of the West African Ebola outbreak is the most pressing, immediate need. A comprehensive assessment of the drivers of Ebola emergence and sustained human-to-human transmission is also needed in order to prepare other countries for importation or emergence of this disease. Such assessment includes identification of country-level protocols and interagency policies for outbreak detection and rapid response, increased understanding of cultural and traditional risk factors within and between nations, delivery of culturally embedded public health education, and regional coordination and collaboration, particularly with governments and health ministries throughout Africa. Public health education is also urgently needed in countries outside of Africa in order to ensure that risk is properly understood and public concerns do not escalate unnecessarily. To prevent future outbreaks, coordinated, multiscale, early warning systems should be developed that make full use of these integrated assessments, partner with local communities in high-risk areas, and provide clearly defined response recommendations specific to the needs of each community.

  5. Investigation on Bridges Connection to Network Carrefour in Existing Roads in Africa Big Cities: The Case of Cotonou in Benin Republic

    Directory of Open Access Journals (Sweden)

    Didier D. Boko-haya

    2016-04-01

    Full Text Available The rapid and continuous growth of populations and vehicles has caused very big traffic volume in most of African big cities. In order to ensure a better distribution of traffic and enables quick access to vehicles, reasonable interchange can be designed to allow greater connection and realizes rapid dividing of vehicles at existing road network carrefour. This paper uses Cotonou, which is the largest urban and economic city of Benin Republic as a case study. Firstly, the paper reviews literatures on history and development of interchanges bridge systems. Based on the case study, the paper then mainly introduces a typical interchange at Godomey carrefour, explains difficulties encountered in engineering design and realizes rapid dividing of vehicles by designing reasonable interchange at Godomey carrefour, so as to accumulate certain experience in the construction of interchange at existing road network carrefour. By studying this case, the research seeks to identify and expand on lessons learned under the first interchange bridge design in Benin. Using the lessons learned government agencies, engineering and construction communities could adopt reasonable structure and construction method according to local conditions based on current situations.

  6. Spatial genetic structuring of baobab (Adansonia digitata, Malvaceae) in the traditional agroforestry systems of West Africa.

    Science.gov (United States)

    Kyndt, Tina; Assogbadjo, Achille E; Hardy, Olivier J; Glele Kakaï, Romain; Sinsin, Brice; Van Damme, Patrick; Gheysen, Godelieve

    2009-05-01

    This study evaluates the spatial genetic structure of baobab (Adansonia digitata) populations from West African agroforestry systems at different geographical scales using AFLP fingerprints. Eleven populations from four countries (Benin, Ghana, Burkina Faso, and Senegal) had comparable levels of genetic diversity, although the two populations in the extreme west (Senegal) had less diversity. Pairwise F(ST) ranged from 0.02 to 0.28 and increased with geographic distance, even at a regional scale. Gene pools detected by Bayesian clustering seem to be a byproduct of the isolation-by-distance pattern rather than representing actual discrete entities. The organization of genetic diversity appears to result essentially from spatially restricted gene flow, with some influences of human seed exchange. Despite the potential for relatively long-distance pollen and seed dispersal by bats within populations, statistically significant spatial genetic structuring within populations (SGS) was detected and gave a mean indirect estimate of neighborhood size of ca. 45. This study demonstrated that relatively high levels of genetic structuring are present in baobab at both large and within-population level, which was unexpected in regard to its dispersal by bats and the influence of human exchange of seeds. Implications of these results for the conservation of baobab populations are discussed.

  7. Infection Prevention and Control for Ebola in Health Care Settings - West Africa and United States.

    Science.gov (United States)

    Hageman, Jeffrey C; Hazim, Carmen; Wilson, Katie; Malpiedi, Paul; Gupta, Neil; Bennett, Sarah; Kolwaite, Amy; Tumpey, Abbigail; Brinsley-Rainisch, Kristin; Christensen, Bryan; Gould, Carolyn; Fisher, Angela; Jhung, Michael; Hamilton, Douglas; Moran, Kerri; Delaney, Lisa; Dowell, Chad; Bell, Michael; Srinivasan, Arjun; Schaefer, Melissa; Fagan, Ryan; Adrien, Nedghie; Chea, Nora; Park, Benjamin J

    2016-01-01

    The 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa underscores the need for health care infection prevention and control (IPC) practices to be implemented properly and consistently to interrupt transmission of pathogens in health care settings to patients and health care workers. Training and assessing IPC practices in general health care facilities not designated as Ebola treatment units or centers became a priority for CDC as the number of Ebola virus transmissions among health care workers in West Africa began to affect the West African health care system and increasingly more persons became infected. CDC and partners developed policies, procedures, and training materials tailored to the affected countries. Safety training courses were also provided to U.S. health care workers intending to work with Ebola patients in West Africa. As the Ebola epidemic continued in West Africa, the possibility that patients with Ebola could be identified and treated in the United States became more realistic. In response, CDC, other federal components (e.g., Office of the Assistant Secretary for Preparedness and Response) and public health partners focused on health care worker training and preparedness for U.S. health care facilities. CDC used the input from these partners to develop guidelines on IPC for hospitalized patients with known or suspected Ebola, which was updated based on feedback from partners who provided care for Ebola patients in the United States. Strengthening and sustaining IPC helps health care systems be better prepared to prevent and respond to current and future infectious disease threats.The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html). PMID:27390018

  8. INTERNATIONALISATION OF BENIN ART WORKS

    Directory of Open Access Journals (Sweden)

    Chika Joseph Ananwa

    2014-07-01

    Full Text Available The artworks of Benin are all about events and achievements, actual or mythical that occurred in the past. These art works was grounded on traditional values and religious beliefs, which also displayed iconographic affinities. Until 15th century A.D, Benin art items were not known outside the ancient Benin kingdom and commanded very little monetary and aesthetic values.The internationalisation of Benin artworks first occurred by accident, because the Europeans that made it possible, were not aware of the art items before coming to the continent. The coming of the Portuguese in 1472 was the first of such event then the Benin artworks were used as exchange for Portuguese goods. The second was the looting of Benin art items, by the British soldiers, in 1897, in what was tagged Benin Punitive Expedition.Other aspects of internationalisation include the display of Benin art items at various museums across the world Benin artworks uploaded in the internet and artefacts on display at various private museums.The aim of this research is to find out why, when and how the Benin artworks became internationalised. This paper also looks at the extent, impact and significances of internationalisation of Benin artworks.

  9. Satellite-Based actual evapotranspiration over drying semiarid terrain in West-Africa

    NARCIS (Netherlands)

    Schuttemeyer, D.; Schillings, Ch.; Moene, A.F.; Bruin, de H.A.R.

    2007-01-01

    A simple satellite-based algorithm for estimating actual evaporation based on Makkink¿s equation is applied to a seasonal cycle in 2002 at three test sites in Ghana, West Africa: at a location in the humid tropical southern region and two in the drier northern region. The required input for the algo

  10. Alien Planorbid (Mollusca, Gastropoda Pulmonata) from South West Africa erroneously recorded as Biomphalaria Pfeifferi

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1974-01-01

    In 1970 I published a record of the freshwater snail Biomphalaria pfeifferi (Krauss, 1848) (fam. Planorbidae) for South West Africa: "Sandamap Farm, Spitzkoppe" (Van Bruggen, 1970: 45, figs. 1-13). Dr. D. S. Brown of the Medical Research Council (London) kindly drew my attention to the fact that jud

  11. Termite diversity across an anthropogenic disturbance gradient in the humid forest zone of West Africa

    NARCIS (Netherlands)

    Eggleton, P.; Bignell, D.E.; Hauser, S.; Dibog, L.; Norgrove, L.; Madong, B.

    2002-01-01

    Data are presented for termite assemblages across an anthropogenic disturbance gradient in the humid forest zone of West and Central Africa. Sampling was by standardised 100 mx2 m transects in: primary forest, several ages of regenerating forest, agroforestry plots, short fallows, mixed food crop fi

  12. Modelling riverflow in the Volta Basin of West Africa : a data-driven framework

    NARCIS (Netherlands)

    Amisigo, B.A.

    2006-01-01

    In this thesis, a riverflow modelling framework developed for monthly riverflow prediction in the 400,000 km2 Volta Basin of West Africa is presented. By analysing available catchment rainfall, runoff and potential evapotranspiration series in the basin using methods such as correlation plots, autor

  13. Vulnerability to changes in malaria transmission due to climate change in West Africa

    Science.gov (United States)

    Yamana, T. K.; Eltahir, E. A.

    2012-12-01

    Malaria transmission in West Africa is strongly tied to climate; temperature affects the development rate of the malaria parasite, as well as the survival of the mosquitoes that transmit the disease, and rainfall is tied to mosquito abundance, as the vector lays its eggs in rain-fed water pools. As a result, the environmental suitability for malaria transmission in this region is expected to change as temperatures rise and rainfall patterns are altered. The vulnerability to changes in transmission varies throughout West Africa. Areas where malaria prevalence is already very high will be less sensitive to changes in transmission. Increases in environmental suitability for malaria transmission in the most arid regions may still be insufficient to allow sustained transmission. However, areas were malaria transmission currently occurs at low levels are expected to be the most sensitive to changes in environmental suitability for transmission. Here, we use data on current environment and malaria transmission rates to highlight areas in West Africa that we expect to be most vulnerable to an increase in malaria under certain climate conditions. We then analyze climate predictions from global climate models in vulnerable areas, and make predictions for the expected change in environmental suitability for malaria transmission using the Hydrology, Entomology and Malaria Transmission Simulator (HYDREMATS), a mechanistic model developed to simulate village-scale response of malaria transmission to environmental variables in West Africa.

  14. Study Abroad in West Africa: An Interdisciplinary Program of International Education

    Science.gov (United States)

    Lowe, Tony B.; Dozier, Cheryl D.; Hunt-Hurst, Patricia; Smith, Bettye P.

    2008-01-01

    This article describes development of an interdisciplinary study abroad program to West Africa at the University of Georgia to help students gain a global perspective. The program is interdisciplinary with several disciplines including social work, clothing and textile, history, and teacher education. This article discusses/highlights a need for a…

  15. A contribution to the knowledge of non-marine Mollusca of South West Africa

    NARCIS (Netherlands)

    Bruggen, van A.C.

    1970-01-01

    The moment to collate scattered notes on South West African non-marine molluscs arrived last year when Mr. B. H. Lamoral of the Natal Museum, Pietermaritzburg (South Africa), entrusted the present author with the study of material obtained during a Council of Scientific and Industrial Research (C.S.

  16. Traditional Apprenticeship in West Africa: Recent Evidence and Policy Options. Discussion Paper No. 34.

    Science.gov (United States)

    Fluitman, Fred

    Apprenticeship is the main avenue to self-employment in micro-enterprises and thus a cornerstone of informal sector development in West Africa. Survey results for Ibadan, Lome, Dakar, Niamey, and other cities demonstrate that apprenticeship as practiced by informal sector artisans is often very similar from one country to the next. Dropout rates…

  17. Simulating malaria transmission in the current and future climate of West Africa

    Science.gov (United States)

    Yamana, T. K.; Bomblies, A.; Eltahir, E. A. B.

    2015-12-01

    Malaria transmission in West Africa is closely tied to climate, as rain fed water pools provide breeding habitat for the anopheles mosquito vector, and temperature affects the mosquito's ability to spread disease. We present results of a highly detailed, spatially explicit mechanistic modelling study exploring the relationships between the environment and malaria in the current and future climate of West Africa. A mechanistic model of human immunity was incorporated into an existing agent-based model of malaria transmission, allowing us to move beyond entomological measures such as mosquito density and vectorial capacity to analyzing the prevalence of the malaria parasite within human populations. The result is a novel modelling tool that mechanistically simulates all of the key processes linking environment to malaria transmission. Simulations were conducted across climate zones in West Africa, linking temperature and rainfall to entomological and epidemiological variables with a focus on nonlinearities due to threshold effects and interannual variability. Comparisons to observations from the region confirmed that the model provides a reasonable representation of the entomological and epidemiological conditions in this region. We used the predictions of future climate from the most credible CMIP5 climate models to predict the change in frequency and severity of malaria epidemics in West Africa as a result of climate change.

  18. Characteristics of Zircon in Placer Deposits along the West Coast of South Africa

    NARCIS (Netherlands)

    Philander, C.; Rozendaal, A.; de Meijer, R.J.

    1999-01-01

    Mining along the west coast of South Africa is dominated by the exploitation of onshore and offshore diamond deposits. The relatively recent discovery of vast resources of heavy minerals in the area has resulted in the establishment of a major related industry. Today, Namakwa Sands is a 10-million-t

  19. Sorghum Quality, Organic Matter Amendments, and Health: Farmers' Perception in Burkina Faso, West Africa

    NARCIS (Netherlands)

    Traore, K.; Stroosnijder, L.

    2005-01-01

    In West Africa, many people suffer from micronutrient deficiencies. Current interventions have low chances of succeeding. Therefore, a food chain approach including local practices is proposed. This article takes local ecological, cultural, and socio-economic aspects into account through a household

  20. Ebola Virus RNA Stability in Human Blood and Urine in West Africa's Environmental Conditions.

    Science.gov (United States)

    Janvier, Frédéric; Delaune, Deborah; Poyot, Thomas; Valade, Eric; Mérens, Audrey; Rollin, Pierre E; Foissaud, Vincent

    2016-02-01

    We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa's environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly.

  1. Potential impact of climate and socioeconomic changes on future agricultural land use in West Africa

    Directory of Open Access Journals (Sweden)

    K. F. Ahmed

    2015-07-01

    agricultural land use is primarily climate-driven in the western part of West Africa and socioeconomically driven in the eastern part. Analysis of results from multiple decision-making scenarios suggests that human adaptation characterized by science-informed decision making to minimize land use could be very effective in many parts of the region.

  2. Organised labour and neo-liberal economic and political reforms in West and Central Africa

    NARCIS (Netherlands)

    Konings, P.J.J.

    2003-01-01

    This article examines the impact of current neoliberal political reforms on trade union performance in West and Central Africa. To what extent have trade unions been involved in the political restructuring of the State? Has political liberalization constrained or enhanced their political influence a

  3. Soil quality improvement for crop production in semi-arid West Africa

    NARCIS (Netherlands)

    Ouédraogo, E.

    2004-01-01

    Soil quality maintenance and crop production improvement in semi-arid West Africa require appropriate cropping technologies, which are ecologically sound and economically viable. Thus, on-farm and on-station experiments have been carried out on the central plateau and in the south of Burkina Faso Th

  4. Climate variability and environmental stress in the Sudan-Sahel zone of West Africa

    DEFF Research Database (Denmark)

    Mertz, Ole; D'haen, Sarah Ann Lise; Maiga, Abdou;

    2012-01-01

    Environmental change in the Sudan-Sahel region of West Africa (SSWA) has been much debated since the droughts of the 1970s. In this article we assess climate variability and environmental stress in the region. Households in Senegal, Mali, Burkina Faso, Niger, and Nigeria were asked about climatic...

  5. World market or regional integration and food security in West Africa

    NARCIS (Netherlands)

    L.J. de Haan (Leo); A. Klaasse Bos (Andries); C. Lutz (Clemens)

    1994-01-01

    textabstractThe problem of food security in West Africa was put on the international agenda in 1974 at the international food conference in Rome following the Great Sahelian Drought of 1968-1973. In those years preoccupation with food security was limited mainly to the Sahel countries and concentrat

  6. The current capacity for training in public health nutrition in West Africa

    NARCIS (Netherlands)

    Pepping, F.

    2010-01-01

    This article is based on a paper prepared for the Workshop on Establishing a Regional Institute for Public Health Nutrition Research and Training in West Africa, convened in Dakar, Senegal, 26-28 March, 2009. Information was gathered mainly prior to this workshop; several responses, however, came in

  7. Epidemiological features and trends of Ebola virus disease in West Africa

    Directory of Open Access Journals (Sweden)

    Ligui Wang

    2015-09-01

    Full Text Available According to a World Health Organization report, the epidemiological features of Ebola virus disease (EVD have changed significantly in West Africa. In this study, the new epidemiological features and prevalence trends for EVD in Guinea, Liberia, and Sierra Leone are described. It was predicted that the Ebola outbreak would end in June 2015.

  8. The Suppression of Internal Unrest in South West Africa (Namibia 1921–1933

    Directory of Open Access Journals (Sweden)

    Andries M. Fokkens

    2013-02-01

    Full Text Available In 1915, the Union of South Africa was requested to administrate South West Africa (SWA (today Namibia on behalf of the British Crown and approved the South West Africa Mandate.  The policies of the Union strongly influenced the administration of SWA, and the administration met with indigenous opposition discontent with the maltreatment.  An attitude of master and servant was prevalent in the mandated territory and the maltreatment of the indigenous people in the mandated territory, racial prejudice, double standards in executing branding laws, enforced indentured labour, dog and hut tax were some of the grievances that the Bondelswarts, the Rehoboth Basters and the Ukuambi had against the SWA Administration.  The Administration perceived these actions as internal unrest and subdued it using police and military resources. Suppressing unrest through force was part of the military policing tradition prevalent in Southern Africa and abroad during the colonial era.  The tactical deployment of ground forces in conjunction with aircraft was an innovation that transformed future operations in SWA between the suppression of the Bondelswarts and the actions against Chief Ipumbu. This article discusses the utilisation of the Union Defence Force (UDF and South West Africa Forces against indigenous people of South West Africa between the two world wars focusing on three incidents over the period 1922 to 1932.  Tactical deployments of ground forces and the application of air power in support of ground forces to suppress internal unrest are explained and discussed.  These discussions provide the military historian with salient facts on physical conditions encountered, the tactics employed and the role of a new weapon system, aircraft, yet to be fully understood in its role as a force multiplier.

  9. Lessons of Risk Communication and Health Promotion - West Africa and United States.

    Science.gov (United States)

    Bedrosian, Sara R; Young, Cathy E; Smith, Laura A; Cox, Joanne D; Manning, Craig; Pechta, Laura; Telfer, Jana L; Gaines-McCollom, Molly; Harben, Kathy; Holmes, Wendy; Lubell, Keri M; McQuiston, Jennifer H; Nordlund, Kristen; O'Connor, John; Reynolds, Barbara S; Schindelar, Jessica A; Shelley, Gene; Daniel, Katherine Lyon

    2016-01-01

    During the response to the 2014-2016 Ebola virus disease (Ebola) epidemic in West Africa, CDC addressed the disease on two fronts: in the epidemic epicenter of West Africa and at home in the United States. Different needs drove the demand for information in these two regions. The severity of the epidemic was reflected not only in lives lost but also in the amount of fear, misinformation, and stigma that it generated worldwide. CDC helped increase awareness, promoted actions to stop the spread of Ebola, and coordinated CDC communication efforts with multiple international and domestic partners. CDC, with input from partners, vastly increased the number of Ebola communication materials for groups with different needs, levels of health literacy, and cultural preferences. CDC deployed health communicators to West Africa to support ministries of health in developing and disseminating clear, science-based messages and promoting science-based behavioral interventions. Partnerships in West Africa with local radio, television, and cell phone businesses made possible the dissemination of messages appropriate for maximum effect. CDC and its partners communicated evolving science and risk in a culturally appropriate way to motivate persons to adapt their behavior and prevent infection with and spread of Ebola virus. Acknowledging what is and is not known is key to effective risk communication, and CDC worked with partners to integrate health promotion and behavioral and cultural knowledge into the response to increase awareness of the actual risk for Ebola and to promote protective actions and specific steps to stop its spread. The activities summarized in this report would not have been possible without collaboration with many U.S. and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html). PMID:27386834

  10. Polyglots, Vernaculars and Global Markets: Variable Trends in West Africa

    Science.gov (United States)

    Adejunmobi, Moradewun

    2004-01-01

    Using a framework from cultural studies and focusing on theories put forward by Pierre Bourdieu, the goal in this paper is to consider how some West Africans interact with foreign languages and cultures in an era of global capital, especially when it comes to the activities of migrants venturing into overseas labour markets and to the production…

  11. Virtual Reference Service in Academic Libraries in West Africa

    Science.gov (United States)

    Sekyere, Kwabena

    2011-01-01

    As technology continues to advance, libraries in Europe and America continue to improve upon their virtual reference services by employing new Web technologies and applying them to existing services. West African academic libraries have begun providing resources electronically to their users but still typically lag behind in the services they…

  12. Forest climbing plants of West Africa: diversity, ecology and management

    NARCIS (Netherlands)

    Bongers, F.J.J.M.; Parren, M.P.E.; Traoré, D.

    2005-01-01

    Climbing plants, including lianas, represent a fascinating component of the ecology of tropical forests. This book focuses on the climbing plants of West African forests. Based on original research, it presents information on the flora (including a checklist), diversity (with overviews at several le

  13. FOREIGN DIRECT INVESTMENT IN AFRICA: SECURING CHINESE INVESTMENT FOR LASTING DEVELOPMENT, THE CASE OF WEST AFRICA

    OpenAIRE

    Paulin Houanye; Sibao Shen

    2012-01-01

    At the end of the 20th century, when investors were actively seeking a favorable and secure place for their capital investment, the African continent rarely crossed their minds. Recent misgivings experienced by financial markets around the world and the increased demand of natural supplies forced investors to focus on Africa. This circumstance, for over a decade, has put all Africa, including both developed and industrialized countries in an embarrassing position with very low foreign investm...

  14. Exploring climatic impacts on water resources in West Niger, Africa

    OpenAIRE

    Vieux, R.E.; Looper, J.P.; Cappelaere, Bernard; Peugeot, Christophe; Maia, A.

    1998-01-01

    Drought persisting in the Sahel for more than 25 years, impacting both surface and subsurface water resources, raises the question whether the hydrological impacts are proportional, dampened, or amplified in response to the climatic change manifested by the drought experienced since 1970. A physically-based distributed model, r.water.fea, applied to a 2.48 km2 endoreic drainage basin, typical of the Niamey area of West Niger, is used to evaluate the sensitivity of the hydrological system to s...

  15. GROWTH AND FORECASTS OF FDI INFLOWS TO NORTH AND WEST AFRICA - AN EMPIRICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    GULSHAN KUMAR

    2009-01-01

    Full Text Available The developing countries of Africa are in severe hunger of FDI inflows as these are receiving a meager 2.8 percent share of global FDI inflows and just 10 percent of aggregate FDI inflows to the developing world. The present study is an effort to examine the growth of FDI inflows to the two largest recipient regions of Africa, through the computation of compound annual growth rates by fitting an exponential function estimated by ordinary least square method. The study detected that during the last three decades, the growth of FDI inflows remained highest for Algeria and Cape Verde, in Northern Africa and West Africa respectively. Both these countries also remained ahead of the others, in their respective regions in growth of FDI as percentage of gross fixed capital formation. The forecasts of FDI inflows to the representative countries of North and West Africa have been generated by using Double Exponential Smoothing model for the period 2009 to 2020. The adequacy of the model is tested by computing autocorrelation coefficients and Ljung-Box Q statistics. The study revealed that in the ensuing decade, Egypt is expected to grow at the fastest pace as far as FDI inflows are concerned.

  16. Available technologies for soil fertility replenishment in East, West and Southern Africa

    International Nuclear Information System (INIS)

    Full text: The central issue for improving agricultural productivity in Africa is how to build up and maintain soil fertility despite the low incomes of smallholder farmers and the increasing land and labour constraints they face. Soil nutrient depletion is a major bottleneck to increased land productivity in the region and has largely contributed to poverty and food insecurity. Soil nutrient depletion occurs when nutrient inflows are less than outflows. Nutrient balances are negative for many cropping systems in Africa indicating that farmers are mining their soils. The critical issue for improving agricultural productivity in Africa is therefore how to build and maintain soil fertility under the different farming systems. Over the years, a number of potential soil fertility management practices have been developed and by researchers. This paper reviews the available technologies for soil fertility replenishment in east, west and southern Africa under the key areas: inorganic fertilizers, animal manures, grain legumes, agroforestry options, soil, water and nutrient conservation, inorganic fertilizers, and integrated nutrient management and highlights the experiences in the application of these options in East, West and Southern Africa. (author)

  17. Drought modes in West Africa and how well CORDEX RCMs simulate them

    Science.gov (United States)

    Diasso, Ulrich; Abiodun, Babatunde J.

    2015-12-01

    This study presents the spatial-temporal structure of droughts in West Africa and evaluates the capability of CORDEX regional climate models in simulating the droughts. The study characterize droughts with the standardized evapo-transpiration index (SPEI) computed using the monthly rainfall and temperature data from the Climatic Research Unit (CRU) and CORDEX models simulation datasets. To obtain the spatial-temporal structure of the droughts, we applied the principal component analysis on the observed and simulated SPEIs and retained the first four principal factors as the leading drought modes over West Africa. The relationship between the drought modes and atmospheric teleconnections was studied using wavelet coherence analysis, while the ability of the CORDEX models to simulate the drought modes was quantified with correlation analysis. The analysis of the relationship between drought modes and atmospheric teleconnections is based on SPEI from observation dataset (CRU). The study shows that about 60 % of spatial-temporal variability in SPEI over West Africa can be grouped into four drought modes. The first drought mode features drought over east Sahel, the second over west Sahel, the third over the Savanna, and the fourth over the Guinea coast. Each drought mode is linked to sea surface temperature anomalies (SSTAs) over tropical areas of Pacific, Atlantic, and Indian Oceans. Most CORDEX models reproduce at least two of the drought modes, but only two models (REMO and CNRM) reproduce all the four drought modes. REMO and WRF give the best simulation of the seasonal variation of the drought mode over the Sahel in March-May and June-August seasons, while CNRM gives the best simulation of seasonal variation in the drought pattern over the Savanna. Results of this study may guide in selecting appropriate CORDEX models for seasonal prediction of droughts and for downscaling projected impacts of global warming on droughts in West Africa.

  18. Understanding the nature and threats of drug trafficking to national and regional security in West Africa

    Directory of Open Access Journals (Sweden)

    Kwesi Aning

    2014-02-01

    Full Text Available Several West African states are threatened by increasingly powerful transnational organised criminal networks. Yet, scholarly work on the nature, characteristics and strength of these groups and how their activities threaten states remains sparse, leading to misunderstandings and inadequate appreciation of the precise nature of the threats they pose to West Africa. This paper seeks to fill these lacunae in our knowledge. It focuses on the nexus between drugs, crime and terrorism. It argues that, the financial spin-offs from criminal activities contribute to the development of opportunistic relationships between criminals and extremist groups that threatens West Africa’s fragile states. The analyses are based on evidence from several West African states, but employ the ongoing crisis in the Sahel, particularly Mali, as an empirical case, to demonstrate how ‘profitable collusion’ among different actors permits hollow states to become edifices that allows corruption, criminality and impunity to flourish.

  19. Rotavirus disease in Guinea-Bissau, West Africa: a review of longitudinal community and hospital studies

    DEFF Research Database (Denmark)

    Fischer, Thea Kølsen; Aaby, Peter; Mølbak, Kåre;

    2010-01-01

    Rotavirus is one of the most common causes of childhood diarrheal disease and deaths in sub-Saharan Africa. This article reviews community- and hospital-based surveillance of rotavirus disease in Bissau, Guinea-Bissau, West Africa. Here, rotavirus infections exhibit a seasonal pattern, with annual...... epidemics occurring during the relatively dry and cooler months, from January to April, and few cases registered from May to December. Most children (74%) experience their first infection before the age of 2 years, and rotavirus has been identified as the most pathogenic of all diarrheal agents during 2...

  20. Social structure of lions (Panthera leo is affected by management in Pendjari Biosphere Reserve, Benin.

    Directory of Open Access Journals (Sweden)

    Etotépé A Sogbohossou

    Full Text Available Lion populations have undergone a severe decline in West Africa. As baseline for conservation management, we assessed the group structure of lions in the Pendjari Biosphere Reserve in Benin. This reserve, composed of one National Park and two Hunting Zones, is part of the WAP transboundary complex of protected areas. Overall mean group size was 2.6±1.7 individuals (n = 296, it was significantly higher in the National Park (2.7±1.7, n = 168 than in the Hunting Zones (2.2±1.5, n = 128. Overall adult sex ratio was even, but significantly biased towards females (0.67 in the National Park and towards males (1.67 in the Hunting Zones. Our results suggest that the Pendjari lion population is affected by perturbations, such as trophy hunting.

  1. Social Structure of Lions (Panthera leo) Is Affected by Management in Pendjari Biosphere Reserve, Benin

    Science.gov (United States)

    Sogbohossou, Etotépé A.; Bauer, Hans; Loveridge, Andrew; Funston, Paul J.; De Snoo, Geert R.; Sinsin, Brice; De Iongh, Hans H.

    2014-01-01

    Lion populations have undergone a severe decline in West Africa. As baseline for conservation management, we assessed the group structure of lions in the Pendjari Biosphere Reserve in Benin. This reserve, composed of one National Park and two Hunting Zones, is part of the WAP transboundary complex of protected areas. Overall mean group size was 2.6±1.7 individuals (n = 296), it was significantly higher in the National Park (2.7±1.7, n = 168) than in the Hunting Zones (2.2±1.5, n = 128). Overall adult sex ratio was even, but significantly biased towards females (0.67) in the National Park and towards males (1.67) in the Hunting Zones. Our results suggest that the Pendjari lion population is affected by perturbations, such as trophy hunting. PMID:24416263

  2. Strategies for regional integration of electricity supply in West Africa

    International Nuclear Information System (INIS)

    To improve peoples' living conditions in West African countries national governments have to considerably reinforce the electricity supply infrastructures. Rehabilitation of the existing installations and construction of new power generation facilities and transmission lines require substantial resources which are tremendously difficult to raise due to the region's specific economical and political conditions. This paper examines the long-term prospects for integrated development of the regional electricity industry and evaluates its advantages by using PLANELEC-Pro, a 'bottom-up' electricity system expansion planning optimisation model. The evolution of regional electricity market is analysed on the basis of two strategies. The 'autarkical' strategy consists in adequate expansion of national power generation systems and the exchanges of electricity between the countries in sub-zones. Another approach referred to as 'integration' strategy is recommended in this article. It leads to fast retirement of the obsolete power plants and the integration of new investment projects at the level of whole West African sub-region. The main finding is that the regional integration strategy is capable to bring about additional benefits in terms of reduced capital expenditures, lower electricity supply cost and the enhanced system's reliability compared to the autarkical strategy

  3. Education and Indigenous Knowledge in Africa: Traditional Bonesetting and Orthopaedic Medicine in West Africa

    Science.gov (United States)

    Ezeanya, Chika A.

    The underlying philosophy of education in contemporary Africa has been established to be alien, and detached from the indigenous knowledge of the people. Modern day formal education in sub-Saharan Africa came about, for the most part, as a result of missionary activities and colonial efforts of Europe. The education bequeathed to Africa was, therefore, fundamentally European in paradigm and lacking in authenticity. The end of colonialism across sub-Saharan Africa did not herald any tangible transformation in the curriculum of study. Education in Africa is still dependent on foreign input for sustainability, thereby stifling research, creativity and innovation. Sustainable development is founded on indigenous knowledge. When such grassroots knowledge assumes the foundation of learning, home-grown development is easily fostered in all sectors of a national economy. In the field of medicine, indigenous knowledge of healing has been considered unscientific by western biomedical practitioners. Since the days of the missionaries, many Africans have considered indigenous medicine to be fetish; the Christian converts would not be associated with its practice and patronage. However, traditional bonesetting has been proven to be highly efficacious with little supernatural content, it continues to attract huge patronage from Africans, cutting across social and religious boundaries. This study attempts an exploration of the disconnect between indigenous knowledge, practices and learning, on the one hand, and formal education in Africa, on the other. With a focus on traditional bonesetting, the study seeks to determine why that branch of indigenous medicine attracts huge patronage, but is granted very little recognition by modern orthopaedic medical education.

  4. Lifestyle and Dietary Factors Associated with the Evolution of Cardiometabolic Risk over Four Years in West-African Adults: The Benin Study

    Directory of Open Access Journals (Sweden)

    Charles Sossa

    2013-01-01

    Full Text Available Aim. To assess in adults from Benin changes in cardiometabolic risk (CMR using both the Framingham risk score (FRS and metabolic syndrome (MetS and to examine the effects of diet, and lifestyles, controlling for location and socioeconomic status. Methods. Apparently healthy subjects (n=541 aged 25–60 years and randomly selected in the largest city, a small town, and rural areas were included in the four-year longitudinal study. Along with CMR factors, socioeconomic, diet and lifestyle data were collected in individual interviews. A food score based on consumption frequency of four “sentinel” food groups (meat and poultry, dairy, eggs, and vegetables was developed. Lifestyle included physical activity, alcohol and tobacco use. Education and income (proxy were the socioeconomic variables. Results. Among the subjects with four-year follow-up data (n=416, 13.5% were at risk at baseline, showing MetS or FRS ≥ 10%. The incidence of MetS and FRS ≥ 10% during follow-up was 8.2% and 5%, respectively. CMR deteriorated in 21% of subjects. Diet and lifestyle mediated location and income effects on CMR evolution. Low food scores and inactivity increased the likelihood of CMR deterioration. Conclusion. Combining MetS and FRS might be appropriate for surveillance purposes in order to better capture CMR and inform preventive measures.

  5. Foraging behaviour of the egg parasitoid Uscana lariophaga towards biological control of bruchid pests in stored cowpea in West Africa.

    NARCIS (Netherlands)

    Alebeek, van F.A.N.

    1996-01-01

    Seed beetles cause considerable losses in traditionally stored cowpea ( Vigna unguiculata Walp.) under subsistence farming conditions in West Africa. The indigenous egg parasitoid Uscana lariophaga Steffan (Hymenoptera; Trichogrammatidae) is evaluated as a candidate for a conservation strategy of bi

  6. Reasons for hospitalization in HIV-infected children in West Africa

    DEFF Research Database (Denmark)

    Dicko, Fatoumata; Desmonde, Sophie; Koumakpai, Sikiratou;

    2014-01-01

    INTRODUCTION: Current knowledge on morbidity and mortality in HIV-infected children comes from data collected in specific research programmes, which may offer a different standard of care compared to routine care. We described hospitalization data within a large observational cohort of HIV...... hospitalized; median age was 3 years [1-8]. Among them, 90 (58%) were confirmed for HIV infection during their stay; 138 (89%) were already receiving cotrimoxazole prophylaxis and 64 children (40%) had initiated antiretroviral therapy (ART). The median length of stay was 13 days (IQR: 7-23); 25 children (16......-infected children in West Africa (IeDEA West Africa collaboration). METHODS: We performed a six-month prospective multicentre survey from April to October 2010 in five HIV-specialized paediatric hospital wards in Ouagadougou, Accra, Cotonou, Dakar and Bamako. Baseline and follow-up data during hospitalization were...

  7. Predicted impacts of climate change on malaria transmission in West Africa

    Science.gov (United States)

    Yamana, T. K.; Eltahir, E. A. B.

    2014-12-01

    Increases in temperature and changes in precipitation due to climate change are expected to alter the spatial distribution of malaria transmission. This is especially true in West Africa, where malaria prevalence follows the current north-south gradients in temperature and precipitation. We assess the skill of GCMs at simulating past and present climate in West Africa in order to select the most credible climate predictions for the periods 2030-2060 and 2070-2100. We then use the Hydrology, Entomology and Malaria Transmission Simulator (HYDREMATS), a mechanistic model of malaria transmission, to translate the predicted changes in climate into predicted changes availability of mosquito breeding sites, mosquito populations, and malaria prevalence. We investigate the role of acquired immunity in determining a population's response to changes in exposure to the malaria parasite.

  8. The possible role of local air pollution in climate change in West Africa

    Science.gov (United States)

    Knippertz, Peter; Evans, Mat J.; Field, Paul R.; Fink, Andreas H.; Liousse, Catherine; Marsham, John H.

    2015-09-01

    The climate of West Africa is characterized by a sensitive monsoon system that is associated with marked natural precipitation variability. This region has been and is projected to be subject to substantial global and regional-scale changes including greenhouse-gas-induced warming and sea-level rise, land-use and land-cover change, and substantial biomass burning. We argue that more attention should be paid to rapidly increasing air pollution over the explosively growing cities of West Africa, as experiences from other regions suggest that this can alter regional climate through the influences of aerosols on clouds and radiation, and will also affect human health and food security. We need better observations and models to quantify the magnitude and characteristics of these impacts.

  9. Dirhinus giffardii (Hymenoptera: Chalcididae, parasitoid affecting Black Soldier Fly production systems in West Africa

    Directory of Open Access Journals (Sweden)

    Emilie Devic

    2015-12-01

    Full Text Available Interest for insect farming is currently growing globally. Conditions in West Africa appear suitable for developing such farming systems that can benefit communities by improving livelihoods, food and feed security or sanitation. In Ghana and Mali, the Black Soldier Fly (Hermetia illucens Linnaeus, 1758 is being produced for waste recycling and animal feed. In a two stages process (egg and larvae production, egg production was hampered by a pupal parasitoid, Dirhinus giffardii Silvestri, 1913 (Hymenoptera: Chalcididae, which reduced future broodstock by almost 72%. This is the first time D. giffardii is reported as a parasitoid of H. illucens pupae and one of the first reports of parasitism in this commercially important fly species. The introduction of precautionary measures is highly recommended for the success of H. illucens production systems in West Africa.

  10. Evaluating the performance of remotely sensed and reanalysed precipitation data over West Africa using HBV light

    Science.gov (United States)

    Jütten, Thomas; Jackisch, Dominik; Diekkrüger, Bernd; Kusche, Jürgen; Eicker, Annette; Springer, Anne

    2016-04-01

    Water is one of the most crucial natural resources in West Africa, where the livelihoods of large parts of the population rely heavily on rain-fed agriculture. Therefore, the modelling of the water balance is an important tool to aid in water resource management. Precipitation is one of most important atmospheric drivers of hydrological models. However, ground-based observation networks are sparse in Western Africa and a further decline in station numbers due to a variety of reasons such as the deterioration of stations or political unrest has been observed in recent years. In ungauged river basins, or basins with insufficiently available precipitation data, several studies have shown that remotely sensed or reanalysed precipitation data may be used to compliment or replace missing information. However, the uncertainties of these datasets over Western Africa are not well examined and a need for further studies is apparent. For validation purposes, precipitation datasets are traditionally compared to in-situ ground measurements. This is not possible in ungauged basins. A new approach to assess the quality of satellite and reanalysis data which is gaining popularity among researchers compares different precipitation datasets using hydrological models. In this so-called hydrological evaluation, ground-truth data is no longer necessary in order to validate a product. The chosen model is calibrated for different precipitation products and the simulated streamflow generated for each product is compared to the measured streamflow. Multiple state of the art satellite and reanalysis precipitation datasets with various spatial resolutions were used in this study, namely: CFSR (0.3125°), CHIRPS (0.05°), CMORPH (0.25°), PERSIANN (0.25°), RFE 2.0 (0.1°), TAMSAT (0.0375°), TRMM 3B42 v7 (0.25°) and TRMM 3B42RT (real time) (0.25°). These datasets were evaluated at the regional as well as local scale using the HBV light conceptual hydrological model for several basins

  11. Understanding changes in terrestrial water storage over West Africa between 2002 and 2014

    Science.gov (United States)

    Ndehedehe, Christopher; Awange, Joseph; Agutu, Nathan; Kuhn, Michael; Heck, Bernhard

    2016-02-01

    With the vast water resources of West Africa coming under threat due to the impacts of climate variability and human influence, the need to understand its terrestrial water storage (TWS) changes becomes very important. Due to the lack of consistent in-situ hydrological data to assist in the monitoring of changes in TWS, this study takes advantage of the Gravity Recovery and Climate Experiment (GRACE) monthly gravity fields to provide estimates of vertically integrated changes in TWS over the period 2002-2014, in addition to satellite altimetry data for the period 1993-2014. In order to understand TWS variability over West Africa, Principal Component Analysis (PCA), a second order statistical technique, and Multiple Linear Regression Analysis (MLRA) are employed. Results show that dominant patterns of GRACE-derived TWS changes are observed mostly in the West Sahel, Guinea Coast, and Middle Belt regions of West Africa. This is probably caused by high precipitation rates at seasonal and inter-annual time scales induced by ocean circulations, altitude and physiographic features. While the linear trend for the spatially averaged GRACE-derived TWS changes over West Africa for the study period shows an increase of 6.85 ± 1.67 mm/yr, the PCA result indicates a significant increase of 20.2 ± 5.78 mm/yr in Guinea, a region with large inter-annual variability in seasonal rainfall, heavy river discharge, and huge groundwater potentials. The increase in GRACE-derived TWS during this period in Guinea, though inconsistent with the lack of a significant positive linear trend in TRMM based precipitation, is attributed to a large water surplus from prolonged wet seasons and lower evapotranspiration rates, leading to an increase in storage and inundated areas over the Guinea region. This increase in storage, which is also the aftermath of cumulative increase in the volume of water not involved in surface runoff, forms the huge freshwater availability in this region. However, the

  12. Overview of main challenges for EarlyWarning Systems for Food Security inWest Africa

    OpenAIRE

    Genesio, L.; Bacci, M.; C. Baron; Diarra, B.; Di Vecchia, A.; Traoré, S.; Hassane, I.; Ndiaye, M.; Philippon, Nathalie; Tarchiani, V.

    2010-01-01

    In West Africa Early Warning Systems (EWSs) for food security have been widely recognized to have contributed in the last twenty years to better face famine emergencies. The improved understanding of the environmental and socio-economic dynamics of the region, a change in the causes for food insecurity and the evolution of Information and Communication Technologies (ICT) have favored the introduction of new approaches and the involvement of a network of stakeholders. In recent years the impro...

  13. Assessment of Undiscovered Oil and Gas Resources of Four West Africa Geologic Provinces

    Science.gov (United States)

    Brownfield, Michael E.; Charpentier, Ronald R.; Cook, Troy A.; Klett, Timothy R.; Pitman, Janet K.; Pollastro, Richard M.; Schenk, Christopher J.; Tennyson, Marilyn E.

    2010-01-01

    Four geologic provinces located along the northwest and west-central coast of Africa recently were assessed for undiscovered oil, natural gas, and natural gas liquids resources as part of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment. Using a geology-based assessment methodology, the USGS estimated mean volumes of 71.7 billion barrels of oil, 187.2 trillion cubic feet of natural gas, and 10.9 billion barrels of natural gas liquids.

  14. Dirhinus giffardii (Hymenoptera: Chalcididae), parasitoid affecting Black Soldier Fly production systems in West Africa

    OpenAIRE

    Emilie Devic; Pierre-Olivier Maquart

    2015-01-01

    Interest for insect farming is currently growing globally. Conditions in West Africa appear suitable for developing such farming systems that can benefit communities by improving livelihoods, food and feed security or sanitation. In Ghana and Mali, the Black Soldier Fly (Hermetia illucens Linnaeus, 1758) is being produced for waste recycling and animal feed. In a two stages process (egg and larvae production), egg production was hampered by a pupal parasitoid, Dirhinus giffardii Silvestri, 19...

  15. Relationships between women's work and demographic behaviour: some research evidence in West Africa.

    OpenAIRE

    Oppong C

    1991-01-01

    Focuses on the inter-relationship between women's labour force participation and the sexual division of labour on the one hand and demographic behavior, especially fertility, on the other in the context of West Africa. Examines linkages between women's roles using data from biographies of women collected in two Ghanaian towns. Highlights the need for new research, e.g. changing patterns of child feeding and child spacing in non-contracepting, agriculturally-based populations. Bibliography.

  16. The Economic Impact of the 2014 Ebola Epidemic : Short and Medium Term Estimates for West Africa

    OpenAIRE

    World Bank Group

    2014-01-01

    The 2014 outbreak of the Ebola virus disease in West Africa has taken a devastating human toll. Although the outbreak originated in rural Guinea, it has hit hardest in Liberia and Sierra Leone, in part because it has reached urban areas in these two countries, a factor that distinguishes this outbreak from previous episodes elsewhere. As of October 3, 2014, there had been 3,431 recorded de...

  17. FOREIGN AID, AID UNCERTAINTY AND PRIVATE INVESTMENT IN WEST AFRICA: AN UNOBSERVED COUNTRY EFFECTS MODEL

    OpenAIRE

    EBERECHUKWU UNEZE

    2012-01-01

    This paper examines whether foreign aid has any impact on private investment in West Africa, taking other determinants of private investment into account. Following from this, the paper investigates whether multilateral aid and bilateral aid affect private investment differently. In a related analysis, the paper examines the impact of aid uncertainty (aid volatility) on private investment. The results show that multilateral aid affects private investment positively, but not bilateral aid, and...

  18. Lassa fever in West Africa: evidence for an expanded region of endemicity.

    Science.gov (United States)

    Sogoba, N; Feldmann, H; Safronetz, D

    2012-09-01

    Lassa virus (LASV) is endemic in Sierra Leone, Guinea and Liberia (known as the Mano River region) and Nigeria and Lassa fever cases from these countries are being reported annually. Recent investigations have found evidence for an expanded endemicity zone between the two known Lassa endemic regions indicating that LASV is more widely distributed throughout the Tropical Wooded Savanna ecozone in West Africa. PMID:22958249

  19. Legume Diversity Patterns in West Central Africa: Influence of Species Biology on Distribution Models

    OpenAIRE

    Manuel de la Estrella; Mateo, Rubén G.; Wieringa, Jan J.; Barbara Mackinder; Jesús Muñoz

    2012-01-01

    OBJECTIVES: Species Distribution Models (SDMs) are used to produce predictions of potential Leguminosae diversity in West Central Africa. Those predictions are evaluated subsequently using expert opinion. The established methodology of combining all SDMs is refined to assess species diversity within five defined vegetation types. Potential species diversity is thus predicted for each vegetation type respectively. The primary aim of the new methodology is to define, in more detail, areas of sp...

  20. Agricultural Land Use Mapping in West Africa Using Multi-sensor Satellite Imagery

    OpenAIRE

    Forkuor, Gerald

    2015-01-01

    Rapid population growth in West Africa has led to expansion in croplands due to the need to grow more food to meet the rising food demand of the burgeoning population. These expansions negatively impact the sub-region's ecosystem, with implications for water and soil quality, biodiversity and climate. In order to appropriately monitor the changes in croplands and assess its impact on the ecosystem and other environmental processes, accurate and up-to-date information on agricultural land use ...

  1. Potential impact of climate and socioeconomic changes on future agricultural land use in West Africa

    OpenAIRE

    Ahmed, Kazi Farzan; Wang, Guiling; You, Liangzhi; Yu, Miao

    2016-01-01

    Agriculture is a key component of anthropogenic land use and land cover changes that influence regional climate. Meanwhile, in addition to socioeconomic drivers, climate is another important factor shaping agricultural land use. In this study, we compare the contributions of climate change and socioeconomic development to potential future changes of agricultural land use in West Africa using a prototype land use projection (LandPro) algorithm. The algorithm is based on a bal...

  2. Matter flows and balances in urban vegetable gardens of Bobo Dioulasso, Burkina Faso (West Africa)

    OpenAIRE

    Lompo, Désiré Jean-Pascal

    2012-01-01

    Many efforts are undertaken for sustaining urban agriculture in African cities. This study therefore investigated nutrient management practices in urban vegetable gardens of Bobo Dioulasso, Burkina Faso (West Africa). Nitrogen (N), phosphorus (P), potassium (K), and carbon (C) fluxes were quantified and nutrient balances calculated for three gardens representing the typical commercial gardening + field crops and livestock system (cGCL) and three gardens representing the commercial gardening +...

  3. Yield gaps and potential agricultural growth in West and Central Africa:

    OpenAIRE

    Nin-Pratt, Alejandro; Johnson, Michael; Magalhaes, Eduardo; You, Liangzhi; DIAO, Xinshen; Chamberlin, Jordan

    2011-01-01

    The authors identify a set of development priorities for agriculture that cut across West Africa at both the country and regional levels to achieve economywide growth goals in the region. To do this we adopt a modeling and analytical framework that involves the integration of spatial analysis to identify yield gaps determining the growth potential of different agricultural activities for areas with similar conditions and an economywide multimarket model to simulate ex ante the economic effect...

  4. Soil fertility management in irrigated rice system in the Sahel and Savana regions of West Africa

    OpenAIRE

    Donovan, C.; Wopereis, M.C.S.; Guindo, D.; Nebie, B.

    1999-01-01

    In irrigated rice production in West Africa, nitrogen (N) and phosphorus (P) fertilizers make up about 20% of total production costs. This research seeks to evaluate whether those fertilizers are profitable under current use by farmers and to identify the factors that may improve fertilizer efficiency and profitability. A combination of farmer surveys and on-farm trials were used to determine actual fertilizer use, costs, and net revenues from fertilizer in key irrigated system in Mali (Offic...

  5. Producer Organizations and Agricultural Technology in West Africa: Institutions that give farmers a voice

    OpenAIRE

    Karim Hussein

    2001-01-01

    Karim Hussein draws on a multi-country study of agricultural research-extension-producer organization linkages in West Africa to argue that producer organizations (POs) have key roles to play in technology development and improving the livelihoods of the poor in developing countries. The role of POs is especially important in the context of globalization. Practical lessons for sustainable livelihoods approaches and promoting empowerment through organization are drawn from this study. Developm...

  6. Fighting Fe deficiency malnutrition in West Africa : an interdisciplinary programme on a food chain approach

    OpenAIRE

    Slingerland, M.A.; TRAORE, K.; Kayodé, A.P.P.; Mitchikpe, C.E.S.

    2006-01-01

    About 2 billion people, mainly women and young children, suffer from iron deficiency. The supply of iron (Fe) falls short when consumed foods have a low Fe content or when absorption of Fe is inhibited by the presence of phytic acid and polyphenols in the diet. Current interventions are dietary diversification, supplementation, fortification and biofortification. In West Africa these interventions have only moderate chances of success due to low purchasing power of households, lack of element...

  7. Potential impact of climate and socioeconomic changes on future agricultural land use in West Africa

    OpenAIRE

    K. F. Ahmed; Wang, G; You, L.; M. Yu

    2015-01-01

    Agriculture is a key component of anthropogenic land use and land cover changes that influence regional climate. Meanwhile, in addition to socioeconomic drivers, climate is another important factor shaping agricultural land use. In this study, we compare the contributions of climate change and socioeconomic development to potential future changes of agricultural land use in West Africa using a prototype land use projection (LandPro) algorithm. The algorithm...

  8. Perspectives on West Africa Ebola Virus Disease Outbreak, 2013–2016

    OpenAIRE

    Jessica R. Spengler; Ervin, Elizabeth D.; Towner, Jonathan S.; Rollin, Pierre E.; Nichol, Stuart T.

    2016-01-01

    The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013–2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations an...

  9. Water Sources in Cape Verde and West Africa. Water in Africa.

    Science.gov (United States)

    Maher, Robert

    The Water in Africa Project was realized over a 2-year period by a team of Peace Corps volunteers, World Wise Schools (WWS) classroom teachers, and WWS staff members. As part of an expanded, detailed design, resources were collected from over 90 volunteers serving in African countries, photos and stories were prepared, and standards-based learning…

  10. Climate change mitigation by carbon stock - the case of semi-arid West Africa

    Science.gov (United States)

    Lykke, A. M.; Barfod, A. S.; Tinggaard Svendsen, G.; Greve, M.; Svenning, J.-C.

    2009-11-01

    Semi-arid West Africa has not been integrated into the afforestation/reforestation (AR) carbon market. Most projects implemented under the Clean Development Mechanism (CDM) have focused on carbon emission reductions from industry and energy consumption, whereas only few (only one in West Africa) have been certified for AR carbon sequestration. A proposed mechanism, Reducing Emissions from Deforestation and Degradation (REDD) to be discussed under COP15 aims to reduce emissions by conserving already existing forests. REDD has high potential for carbon stocking at low costs, but focuses primarily on rain forest countries and excludes semi-arid West Africa from the preliminary setup. African savannas have potential to store carbon in the present situation with degrading ecosystems and relatively low revenues from crops and cattle, especially if it is possible to combine carbon stocking with promotion of secondary crops such as food resources and traditional medicines harvested on a sustainable basis. Methods for modelling and mapping of potential carbon biomass are being developed, but are still in a preliminary state. Although economic benefits from the sale of carbon credits are likely to be limited, carbon stocking is an interesting option if additional benefits are considered such as improved food security and protection of biodiversity.

  11. Safe and Effective Deployment of Personnel to Support the Ebola Response - West Africa.

    Science.gov (United States)

    Rouse, Edward N; Zarecki, Shauna Mettee; Flowers, Donald; Robinson, Shawn T; Sheridan, Reed J; Goolsby, Gary D; Nemhauser, Jeffrey; Kuwabara, Sachiko

    2016-07-08

    From the initial task of getting "50 deployers within 30 days" into the field to support the 2014-2016 Ebola virus disease (Ebola) epidemic response in West Africa to maintaining well over 200 staff per day in the most affected countries (Guinea, Liberia, and Sierra Leone) during the peak of the response, ensuring the safe and effective deployment of international responders was an unprecedented accomplishment by CDC. Response experiences shared by CDC deployed staff returning from West Africa were quickly incorporated into lessons learned and resulted in new activities to better protect the health, safety, security, and resiliency of responding personnel. Enhanced screening of personnel to better match skill sets and experience with deployment needs was developed as a staffing strategy. The mandatory predeployment briefings were periodically updated with these lessons to ensure that staff were aware of what to expect before, during, and after their deployments. Medical clearance, security awareness, and resiliency programs became a standard part of both predeployment and postdeployment activities. Response experience also led to the identification and provision of more appropriate equipment for the environment. Supporting the social and emotional needs of deployed staff and their families also became an agency focus for care and communication. These enhancements set a precedent as a new standard for future CDC responses, regardless of size or complexity.The activities summarized in this report would not have been possible without collaboration with many U.S and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html).

  12. Nutrient content of four edible wild plants from west Africa.

    Science.gov (United States)

    Glew, Robert S; Vanderjagt, Dorothy J; Chuang, L-T; Huang, Y-S; Millson, M; Glew, Robert H

    2005-12-01

    Non-cereal plant foods in the Western Sahel of Africa contribute significantly to the diets of local residents, especially during periods of grain shortages. In this paper, we analyze four such plant foods including diyan kwakwa (nut of coconut palm, Cocos nucifera L.), muricin giginya (young shoot of Borassus aethiopum), tsamiya biri (fruit of the tree, Tamarindus indica), and yari (a mixture of lichens, mainly Rimelia reticulate) that grows on ebony trees (Diospyros mespiliformis). They were analyzed for their content of amino acids, fatty acids, and minerals. Although diyan kwakwa contained the highest protein content (27.1%), its protein quality fell below the WHO standard in 3 of 8 essential amino acid categories. Yari and muricin giginya contained moderate levels of good quality protein. Only diyan kwakwa contained calorically significant amount of total fatty acid (24.7%); however, none of the plants contained useful amounts of the essential fatty acids, linoleic acid, or alpha-linolenic acid. All four plants contained useful amounts of zinc (> 12 microg/g dry weight), while yari contained the most calcium (14.7 mg/g dry weight) and iron (1.41 mg/g), and diyan kwakwa the most copper. All the four plant foods contained lesser amounts of magnesium, molybdenum, or selenium. These data indicate that the four plants contain useful amounts of various essential nutrients that could supplement the diets of populations inhabiting the Western Sahel.

  13. International Commodity Markets, Local Food Prices and Environment in West Africa

    Science.gov (United States)

    Brown, M. E.; Hintermann, B.; Higgins, N.

    2008-12-01

    The recent massive increase in food and energy prices in the past five years, coupled with the awareness of the long term challenges of climate change to small holder agriculture in Africa has brought the issue of food security for the world's poorest people to the forefront once again. Asymmetric and limited integration of local commodity markets in West Africa highlights the weak position of Africa's rural countries in the face of climate change and demographic expansion. This paper will describe the functioning of local informal food markets in West African over the past twenty years and evaluate the impact of their limited integration with each other and with global commodity markets. Satellite remote sensing of vegetation has been used as a proxy for agricultural production in economic models to improve prediction of large swings in prices from year to year due to differences in supply. As demand increases, improvements in market functioning will be necessary to counter likely increases in production variability. Increasing Africa's stability in the face of climate change will require investment in agricultural production and transportation infrastructure in order to ensure an affordable flow of food to people in these extremely poor, landlocked countries.

  14. Air mass origins influencing TTL chemical composition over West Africa during 2006 summer monsoon

    Directory of Open Access Journals (Sweden)

    K. S. Law

    2010-11-01

    Full Text Available Trace gas and aerosol data collected in the tropical tropopause layer (TTL between 12–18.5 km by the M55 Geophysica aircraft as part of the SCOUT-AMMA campaign over West Africa during the summer monsoon in August 2006 have been analysed in terms of their air mass origins. Analysis of domain filling back trajectories arriving over West Africa, and in the specific region of the flights, showed that the M55 flights were generally representative of air masses arriving over West Africa during the first 2 weeks of August, 2006. Air originating from the mid-latitude lower stratosphere was under-sampled (in the mid-upper TTL whilst air masses uplifted from central Africa (into the lower TTL were over-sampled in the latter part of the campaign. Signatures of recent (previous 10 days origins were superimposed on the large-scale westward flow over West Africa. In the lower TTL, air masses were impacted by recent local deep convection over Africa at the level of main convective outflow (350 K, 200 hPa and on certain days up to 370 K (100 hPa. Estimates of the fraction of air masses influenced by local convection vary from 10 to 50% depending on the method applied and from day to day during the campaign. The analysis shows that flights on 7, 8 and 11 August were more influenced by local convection than on 4 and 13 August allowing separation of trace gas and aerosol measurements into "convective" and "non-convective" flights. Strong signatures, particularly in species with short lifetimes (relative to CO2 like CO, NO and fine-mode aerosols were seen during flights most influenced by convection up to 350–365 K. Observed profiles were also constantly perturbed by uplift (as high as 39% of air masses from the mid to lower troposphere over Asia, India, and oceanic regions resulting in import of clean oceanic (e.g. O3-poor or polluted air masses from Asia (high O3, CO, CO2 into West Africa. Thus, recent uplift of CO

  15. Air mass origins influencing TTL chemical composition over West Africa during 2006 summer monsoon

    Directory of Open Access Journals (Sweden)

    K. S. Law

    2010-06-01

    Full Text Available Trace gas and aerosol data collected in the tropical tropopause layer (TTL between 12–18.5 km by the M55 Geophysica aircraft as part of the SCOUT-AMMA campaign over West Africa during the summer monsoon in August 2006 have been analysed in terms of their air mass origins. Analysis of domain filling back trajectories arriving over West Africa, and in the specific region of the flights, showed that the M55 flights were generally representative of air masses arriving over West Africa during the first 2 weeks of August, 2006. Air originating from the mid-latitude lower stratosphere was under-sampled (in the mid-upper TTL whilst air masses uplifted from central Africa (into the lower TTL were over-sampled in the latter part of the campaign. Signatures of recent (previous 10 days origins were superimposed on the large-scale westerly flow over West Africa. In the lower TTL, air masses were impacted by recent local deep convection over Africa at the level of main convective outflow (350 K, 200 hPa and on certain days up to 370 K (100 hPa. Estimates of the fraction of air masses influenced by local convection vary from 10 to 50% depending on the method applied and from day to day during the campaign. The analysis shows that flights on 7, 8 and 11 August were more influenced by local convection than on 4 and 13 August allowing separation of trace gas and aerosol measurements into ''convective'' and ''non-convective'' flights. Strong signatures, particularly in short-lived species like CO, NO and fine-mode aerosols were seen during flights most influenced by convection up to 350–365 K. Observed profiles were also constantly perturbed by uplift (as high as 39% of air masses from the mid to lower troposphere over Asia, India, and oceanic regions resulting in import of clean oceanic (e.g., O3-poor or polluted air masses from Asia (high O3, CO, CO2 into West Africa. Thus, recent uplift of CO2 over Asia may

  16. The impact of civil war on forest wildlife in West Africa: Mammals in Gola Forest, Sierra Leone

    NARCIS (Netherlands)

    Lindsell, J.A.; Klop, E.; Siaka, A.M.

    2011-01-01

    Human conflicts may sometimes benefit wildlife by depopulating wilderness areas but there is evidence from Africa that the impacts tend to be negative. The forested states of West Africa have experienced much recent human conflict but there have been no assessments of impacts on the wildlife. We con

  17. Prostate cancer disparities in Black men of African descent: a comparative literature review of prostate cancer burden among Black men in the United States, Caribbean, United Kingdom, and West Africa

    Directory of Open Access Journals (Sweden)

    Reams R Renee

    2009-02-01

    Full Text Available Abstract Background African American men have the highest prostate cancer morbidity and mortality rates than any other racial or ethnic group in the US. Although the overall incidence of and mortality from prostate cancer has been declining in White men since 1991, the decline in African American men lags behind White men. Of particular concern is the growing literature on the disproportionate burden of prostate cancer among other Black men of West African ancestry in the Caribbean Islands, United Kingdom and West Africa. This higher incidence of prostate cancer observed in populations of African descent may be attributed to the fact that these populations share ancestral genetic factors. To better understand the burden of prostate cancer among men of West African Ancestry, we conducted a review of the literature on prostate cancer incidence, prevalence, and mortality in the countries connected by the Transatlantic Slave Trade. Results Several published studies indicate high prostate cancer burden in Nigeria and Ghana. There was no published literature for the countries Benin, Gambia and Senegal that met our review criteria. Prostate cancer morbidity and/or mortality data from the Caribbean Islands and the United Kingdom also provided comparable or worse prostate cancer burden to that of US Blacks. Conclusion The growing literature on the disproportionate burden of prostate cancer among other Black men of West African ancestry follows the path of the Transatlantic Slave Trade. To better understand and address the global prostate cancer disparities seen in Black men of West African ancestry, future studies should explore the genetic and environmental risk factors for prostate cancer among this group.

  18. Chemical composition and insecticidal activity of plant essential oils from Benin against Anopheles gambiae (Giles)

    OpenAIRE

    Bossou, Annick; Mangelinckx, Sven; Yedomonhan, Hounnankpon; Boko, Pelagie M; Akogbeto, Martin C; De Kimpe, Norbert; Avlessi, Felicien; Sohounhloue, Dominique CK

    2013-01-01

    Background Insecticide resistance in sub-Saharan Africa and especially in Benin is a major public health issue hindering the control of the malaria vectors. Each Anopheles species has developed a resistance to one or several classes of the insecticides currently in use in the field. Therefore, it is urgent to find alternative compounds to conquer the vector. In this study, the efficacies of essential oils of nine plant species, which are traditionally used to avoid mosquito bites in Benin, we...

  19. Impact of climate change on drylands with a focus on West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, A.J.; Verhagen, A.; Ruben, R. (eds.) [Impact of Climate Change on Drylands ICCD, Wageningen (Netherlands)

    2001-07-01

    The research effort started with a geographical inventory of all tropical and sub-tropical drylands to map the diversity in aridity, land degradation, population densities and urbanisation of the world's drylands, and to put the drylands of West Africa in perspective. It also guided a choice of in-depth study regions within West Africa. The scenario analysis shows a wide variety of outcomes, but with rather strong suggestions that most of dryland West Africa is expected to become a lot dryer. The consequences of these projections are an increase in high-risk environments for agriculture, including a southward shift of the and and semi-arid zones. Changes in rainfall distribution could mean an additional stress on agricultural production in these areas. Simulation studies clearly reveal a shift of the onset of the growing season and lower yield levels. To understand farmers' behaviour in West African drylands in preparing (Insuring) for dryer conditions and for agro-climatological droughts, in coping with droughts and adverse production conditions, and in adapting to changed conditions afterwards, we looked at their performance before, during and after drought years in the past identifying several adaptation strategies and policy recommendations. The conclusions are not very grim, contrary to the much-painted 'picture of doom' for Africa. West Africa's shock experience in the 1970s and 1980s did have the result that it became much better prepared for possible new drought shocks, and that its agricultural production performance in the 1990s (when rainfall became considerably better) improved. The future for the Sahel is not necessarily gloomy. However, system breakdown can occur during droughts. One may fear that in those situations religion will be used as a major catalyst for political support to exclusive claims (Islam versus Christianity and religious sub-groups versus sub-groups) and may result in massive violence and rapid deterioration

  20. THE QUEST FOR A SUPRANATIONAL ENTITY IN WEST AFRICA: CAN THE ECONOMIC COMMUNITY OF WEST AFRICAN STATES ATTAIN THE STATUS?

    Directory of Open Access Journals (Sweden)

    Jadesola O Lokulo-Sodipe

    2013-08-01

    Full Text Available To reflect the growing trends in the international scene and in furtherance of the objective of its Revised 1993 Treaty, the Economic Community of West African States (ECOWAS summit in December 2006 revolutionised the structure of ECOWAS by re-designating the Executive Secretariat into a quasi-independent commission headed by a President with a Vice President and seven commissioners. The rationale behind the revision was to make ECOWAS a supranational entity. This article considers whether or not a supranational system is essential for the attainment of ECOWAS' objectives. It asks if the conditions for an effective supranational system are in place in the West African sub-region which could provide a solid foundation for its success and why the quest for a supranational system has not yielded any fruitful result in West Africa. It argues that a retreat from the quest for supranationalism and a return to an inter-governmental system would be a retreat rather than the way forward, and expresses the need for the course of action to be sustained courageously till the impact of integration begins to emerge, and the disguised, patriotic impulse of states to protect their national sovereignty gives way to the full manifestation of ECOWAS as a supranational entity.

  1. The problem of suboptimal complementary feeding practices in West Africa: what is the way forward?

    Science.gov (United States)

    Issaka, Abukari I; Agho, Kingsley E; Page, Andrew N; Burns, Penelope L; Stevens, Garry J; Dibley, Michael J

    2015-10-01

    The objective of this paper was to review the policy implications of inadequate complementary feeding among children aged 6-23 months in West Africa. The review was undertaken from the initial results and findings from a series of studies on the comparison of complementary feeding indicators among children aged 6-23 months in four anglophone and seven francophone West African countries. It also examined a study of the determinants of suboptimal complementary feeding practices among children aged 6-23 months in those countries. Among the four complementary feeding indicators, it was only the introduction of solid, semi-solid or soft foods that was adequate among children in all the West African countries surveyed. The rates of the other complementary feeding indicators were found to be inadequate in all countries surveyed, although relatively better among children in the anglophone countries. Alarmingly, low rates of minimum acceptable diet were reported among children from both the anglophone and the francophone countries. Infants 6-11 months of age, children living in poor households, administrative/geographical regional differences and mothers' access to the media were some of the common risk factors for optimal complementary feeding practices in these countries. Assessing complementary feeding indicators and determinants of suboptimal complementary feeding practices in these West African countries is crucial to improving infant and young child feeding practices. It is recommended that governments and stakeholders of the West African countries studied make greater efforts to improve these critical practices in order to reduce child morbidity and mortality in the West Africa sub-region. Intervention studies on complementary feeding should target those socio-demographic factors that pose risks to optimal complementary feeding. PMID:26364791

  2. The WASCAL regional climate simulations for West Africa - how to add value to existing climate projections

    Science.gov (United States)

    Arnault, J.; Heinzeller, D.; Klein, C.; Dieng, D.; Smiatek, G.; Bliefernicht, J.; Sylla, M. B.; Kunstmann, H.

    2015-12-01

    With climate change being one of the most severe challenges to rural Africa in the 21st century, West Africa is facing an urgent need to develop effective adaptation and mitigation measures to protect its constantly growing population. WASCAL (West African Science Service Center on Climate Change and Adapted Land Use) is a large-scale research-focused program designed to enhance the resilience of human and environmental systems to climate change and increased variability. An integral part of its climate services is the provisioning of a new set of high resolution, ensemble-based regional climate change scenarios for the region of West Africa. In this contribution, we present the overall concept of the WASCAL regional climate projections and provide information on the dissemination of the data. We discuss the model performance over the validation period for two of the three regional climate models employed, the Weather Research & Forecasting Tool (WRF) and the Consortium for Small-scale Modeling Model COSMO in Climate Mode (COSMO-CLM), and give details about a novel precipitation database used to verify the models. Particular attention is paid to the representation of the dynamics of the West African Summer Monsoon and to the added value of our high resolution models over existing data sets. We further present results on the climate change signal obtained from the WRF model runs for the periods 2020-2050 and 2070-2100 and compare them to current state-of-the-art projections from the CORDEX project. As an example, the figure shows the different climate change signals obtained for the total annual rainfall with respect to the 1980-2010 mean (WRF-E: WASCAL 12km high-resolution run MPI-ESM + WRFV3.5.1, CORDEX-E: 50km medium-resolution run MPI-ESM + RCA4, CORDEX-G: 50km medium-resolution run GFDL-ESM + RCA4).

  3. Effects of vegetation feedback on future climate change over West Africa

    Science.gov (United States)

    Yu, Miao; Wang, Guiling; Pal, Jeremy S.

    2016-06-01

    This study investigates the impact of climate-vegetation interaction on future climate changes over West Africa using a regional climate model with synchronous coupling between climate and natural vegetation, the RegCM4.3.4-CLM-CN-DV. Based on the lateral boundary conditions supplied by MIROC-ESM and CESM under the greenhouse gas Representative Concentration Pathway 8.5, significant increase of vegetation density is projected over the southern part of Sahel, with an increase of leaf area index and a conversion from grass to woody plants around 7-10°N of Sahel. Regardless of whether the model treats vegetation as static or dynamic, it projects an increase of precipitation in eastern Sahel and decrease in the west. The feedback due to projected vegetation change tends to cause a wet signal, enhancing the projected increase or alleviate the decrease of precipitation in JJA in the areas of projected vegetation increase. Its impact is negligible in DJF. Vegetation feedback slightly enhances projected warming in most of West Africa during JJA, but has a significant cooling effect during DJF in regions of strong vegetation changes. Future changes of surface runoff are projected to follow the direction of precipitation changes. While dynamic vegetation feedback enhances the projected increase of soil water content in JJA, it has a drying effect in DJF. The magnitude of projected ET changes is reduced in JJA and increased in DJF due to vegetation dynamics. A high sensitivity of climate projection to dynamic vegetation feedback was found mainly in semiarid areas of West Africa, with little signal in the wet tropics.

  4. Trends in floods in West Africa: analysis based on 11 catchments in the region

    Science.gov (United States)

    Nka, B. N.; Oudin, L.; Karambiri, H.; Paturel, J. E.; Ribstein, P.

    2015-11-01

    After the drought of the 1970s in West Africa, the variability in rainfall and land use changes mostly affected flow, and recently flooding has been said to be an increasingly common occurrence throughout the whole of West Africa. These changes have raised many questions about the impact of climate change on the flood regimes in West African countries. This paper investigates whether floods are becoming more frequent or more severe and to what extent climate patterns have been responsible for these changes. We analyzed the trends in the floods occurring in 11 catchments within West Africa's main climate zones. The methodology includes two methods for sampling flood events, namely the AM (annual maximum) method and the POT (peak over threshold), and two perspectives of analysis are presented: long-term analysis based on two long flood time series and a regional perspective involving 11 catchments with shorter series. The Mann-Kendall trend test and the Pettitt break test were used to detect nonstationarities in the time series. The trends detected in flood time series were compared to the rainfall index trends and vegetation indices using contingency tables in order to identify the main driver of change in flood magnitude and flood frequency. The relation between the flood index and the physiographic index was evaluated through a success criterion and the Cramer criterion calculated from the contingency tables. The results show the existence of trends in flood magnitude and flood frequency time series, with two main patterns. Sahelian floods show increasing flood trends and one Sudanian. catchment presents decreasing flood trends. For the overall catchments studied, trends in the maximum 5-day consecutive rainfall index (R5d) show good coherence with trends in flood, while the trends in normalized difference vegetation indices (NDVIs) do not show a significant agreement with flood trends, meaning that this index has possibly no impact on the behavior of floods in

  5. Determinants of soybean [Glycine max (L.) Merrill] production system in Benin

    OpenAIRE

    Charlotte Carmelle Zoundji; Pascal Houngnandan; Houinsou Dedehouanou; Fatiou Toukourou

    2015-01-01

    Present study was conducted to analyze the soybean production system in Benin. Data were collected from 324 soybean producers selected from the three major soybean-producing agro-ecological areas i.e. agro-ecological zone 3 (southern Borgou), agro-ecological zone 4 (West Atacora) and agro-ecological zone 5 (Cotton zone of the Centre of Benin). A participatory research approach with group discussions followed by individual interviews was carried out for extracting the information f...

  6. Forecasting droughts in West Africa: Operational practice and refined seasonal precipitation forecasts

    Science.gov (United States)

    Bliefernicht, Jan; Siegmund, Jonatan; Seidel, Jochen; Arnold, Hanna; Waongo, Moussa; Laux, Patrick; Kunstmann, Harald

    2016-04-01

    Precipitation forecasts for the upcoming rainy seasons are one of the most important sources of information for an early warning of droughts and water scarcity in West Africa. The meteorological services in West Africa perform seasonal precipitation forecasts within the framework of PRESAO (the West African climate outlook forum) since the end of the 1990s. Various sources of information and statistical techniques are used by the individual services to provide a harmonized seasonal precipitation forecasts for decision makers in West Africa. In this study, we present a detailed overview of the operational practice in West Africa including a first statistical assessment of the performance of the precipitation forecasts for drought situations for the past 18 years (1998 to 2015). In addition, a long-term hindcasts (1982 to 2009) and a semi-operational experiment for the rainy season 2013 using statistical and/or dynamical downscaling are performed to refine the precipitation forecasts from the Climate Forecast System Version 2 (CFSv2), a global ensemble prediction system. This information is post-processed to provide user-oriented precipitation indices such as the onset of the rainy season for supporting water and land use management for rain-fed agriculture. The evaluation of the individual techniques is performed focusing on water-scarce regions of the Volta basin in Burkina Faso and Ghana. The forecasts of the individual techniques are compared to state-of-the-art global observed precipitation products and a novel precipitation database based on long-term daily rain-gage measurements provided by the national meteorological services. The statistical assessment of the PRESAO forecasts indicates skillful seasonal precipitation forecasts for many locations in the Volta basin, particularly for years with water deficits. The operational experiment for the rainy season 2013 illustrates the high potential of a physically-based downscaling for this region but still shows

  7. Assessing climate adaptation options and uncertainties for cereal systems in West Africa

    Science.gov (United States)

    Guan, K.; Sultan, B.; Biasutti, M.; Lobell, D. B.

    2015-12-01

    The already fragile agriculture production system in West Africa faces further challenges in meeting food security in the coming decades, primarily due to a fast increasing population and risks of climate change. Successful adaptation of agriculture should not only benefit in the current climate but should also reduce negative (or enhance positive) impacts for climate change. Assessment of various possible adaptation options and their uncertainties provides key information for prioritizing adaptation investments. Here, based on the several robust aspects of climate projections in this region (i.e. temperature increases and rainfall pattern shifts), we use two well-validated crop models (i.e. APSIM and SARRA-H) and an ensemble of downscaled climate forcing to assess five possible and realistic adaptation options (late sowing, intensification, thermal time increase, water harvesting and increased resilience to heat stress) in West Africa for the staple crop production of sorghum. We adopt a new assessment framework to account for both the impacts of adaptation options in current climate and their ability to reduce impacts of future climate change, and also consider changes in both mean yield and its variability. Our results reveal that most proposed "adaptation options" are not more beneficial in the future than in the current climate, i.e. not really reduce the climate change impacts. Increased temperature resilience during grain number formation period is the main adaptation that emerges. We also find that changing from the traditional to modern cultivar, and later sowing in West Sahel appear to be robust adaptations.

  8. Geochemical mapping using stream sediments in west-central Nigeria: Implications for environmental studies and mineral exploration in West Africa

    International Nuclear Information System (INIS)

    This paper provides an overview of regional geochemical mapping using stream sediments from central and south-western Nigeria. A total of 1569 stream sediment samples were collected and 54 major and trace elements determined by ICP-MS and Au, Pd and Pt by fire assay. Multivariate statistical techniques (e.g., correlation analysis and principal factor analysis) were used to explore the data, following appropriate data transformation, to understand the data structure, investigate underlying processes controlling spatial geochemical variability and identify element associations. Major geochemical variations are controlled by source geology and provenance, as well as chemical weathering and winnowing processes, more subtle variations are a result of land use and contamination from anthropogenic activity. This work has identified placer deposits of potential economic importance for Au, REE, Ta, Nb, U and Pt, as well as other primary metal deposits. Areas of higher As and Cr (>2 mg/kg and >70 mg/kg respectively) are associated with Mesozoic and younger coastal sediments in SW Nigeria. High stream sediment Zr concentrations (mean >0.2%), from proximal zircons derived from weathering of basement rocks, have important implications for sample preparation and subsequent analysis due to interferences. Associated heavy minerals enriched in high field strength elements, and notably rare earths, may also have important implications for understanding magmatic processes within the basement terrain of West Africa. This study provides important new background/baseline geochemical values for common geological domains in Nigeria (which extend across other parts of West Africa) for assessment of contamination from urban/industrial land use changes and mining activities. Regional stream sediment mapping is also able to provide important new information with applications across a number of sectors including agriculture, health, land use and planning.

  9. Local cost sharing in Bamako Initiative systems in Benin and Guinea: assuring the financial viability of primary health care.

    Science.gov (United States)

    Soucat, A; Levy-Bruhl, D; Gbedonou, P; Drame, K; Lamarque, J P; Diallo, S; Osseni, R; Adovohekpe, P; Ortiz, C; Debeugny, C; Knippenberg, R

    1997-06-01

    centres. This analysis showed that the size of the target population of the health centre is a key determinant of cost-recovery in both countries. In addition, in Guinea the utilization of curative care linked to geographical access and in Benin the average revenue per case linked to the number of deliveries proved to be additional factors of importance. In best performing centres, financial viability improved over time in both countries between 1990 and 1993. Finally, the implications of these conclusions for the planning of health centre revitalization in West Africa are discussed.

  10. Social and Cutural Aspects of HIV and AIDS in West Africa

    DEFF Research Database (Denmark)

    Samuelsen, Helle; Ostergaard, Lise Rosendal; Norgaard, Ole

    2012-01-01

    through a literature search in seven scientific, bibliographical databases. Searches included terms related to qualitative studies combined with various terms related to HIV/AIDS. The results of this narrative review show that there was a geographical concentration on Nigeria, Ghana, Burkina Faso...... and the non-optimal access to treatment in West Africa. Also, more research is needed on men and their exposure to HIV/AIDS, as well as on the role of concurrent partnership in the spread of HIV.......With the increasing focus on the role of social aspects of the HIV epidemic in sub-Saharan Africa, the need for an overview of existing research dealing with such issues has become more urgent. The objective of this article is to provide a thematic overview of existing qualitative research on HIV...

  11. Discovering Karima (Euphorbiaceae, a New Crotonoid Genus from West Tropical Africa Long Hidden within Croton.

    Directory of Open Access Journals (Sweden)

    Martin Cheek

    Full Text Available Croton scarciesii (Euphorbiaceae-Crotonoideae, a rheophytic shrub from West Africa, is shown to have been misplaced in Croton for 120 years, having none of the diagnostic characters of that genus, but rather a set of characters present in no known genus of the family. Pollen analysis shows that the new genus Karima belongs to the inaperturate crotonoid group. Analysis of a concatenated molecular dataset combining trnL-F and rbcL sequences positioned Karima as sister to Neoholstia from south eastern tropical Africa in a well-supported clade comprised of genera of subtribes Grosserineae and Neoboutonieae of the inaperturate crotonoid genera. Several morphological characters support the relationship of Karima with Neoholstia, yet separation is merited by numerous characters usually associated with generic rank in Euphorbiaceae. Quantitative ecological data and a conservation assessment supplement illustrations and descriptions of the taxon.

  12. Discovering Karima (Euphorbiaceae), a New Crotonoid Genus from West Tropical Africa Long Hidden within Croton

    Science.gov (United States)

    Cheek, Martin; Challen, Gill; Lebbie, Aiah; Banks, Hannah; Barberá, Patricia; Riina, Ricarda

    2016-01-01

    Croton scarciesii (Euphorbiaceae-Crotonoideae), a rheophytic shrub from West Africa, is shown to have been misplaced in Croton for 120 years, having none of the diagnostic characters of that genus, but rather a set of characters present in no known genus of the family. Pollen analysis shows that the new genus Karima belongs to the inaperturate crotonoid group. Analysis of a concatenated molecular dataset combining trnL-F and rbcL sequences positioned Karima as sister to Neoholstia from south eastern tropical Africa in a well-supported clade comprised of genera of subtribes Grosserineae and Neoboutonieae of the inaperturate crotonoid genera. Several morphological characters support the relationship of Karima with Neoholstia, yet separation is merited by numerous characters usually associated with generic rank in Euphorbiaceae. Quantitative ecological data and a conservation assessment supplement illustrations and descriptions of the taxon. PMID:27049519

  13. Safe and Effective Deployment of Personnel to Support the Ebola Response - West Africa.

    Science.gov (United States)

    Rouse, Edward N; Zarecki, Shauna Mettee; Flowers, Donald; Robinson, Shawn T; Sheridan, Reed J; Goolsby, Gary D; Nemhauser, Jeffrey; Kuwabara, Sachiko

    2016-01-01

    From the initial task of getting "50 deployers within 30 days" into the field to support the 2014-2016 Ebola virus disease (Ebola) epidemic response in West Africa to maintaining well over 200 staff per day in the most affected countries (Guinea, Liberia, and Sierra Leone) during the peak of the response, ensuring the safe and effective deployment of international responders was an unprecedented accomplishment by CDC. Response experiences shared by CDC deployed staff returning from West Africa were quickly incorporated into lessons learned and resulted in new activities to better protect the health, safety, security, and resiliency of responding personnel. Enhanced screening of personnel to better match skill sets and experience with deployment needs was developed as a staffing strategy. The mandatory predeployment briefings were periodically updated with these lessons to ensure that staff were aware of what to expect before, during, and after their deployments. Medical clearance, security awareness, and resiliency programs became a standard part of both predeployment and postdeployment activities. Response experience also led to the identification and provision of more appropriate equipment for the environment. Supporting the social and emotional needs of deployed staff and their families also became an agency focus for care and communication. These enhancements set a precedent as a new standard for future CDC responses, regardless of size or complexity.The activities summarized in this report would not have been possible without collaboration with many U.S and international partners (http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/partners.html). PMID:27387289

  14. Potential impact of climate and socioeconomic changes on future agricultural land use in West Africa

    Science.gov (United States)

    Farzan Ahmed, Kazi; Wang, Guiling; You, Liangzhi; Yu, Miao

    2016-02-01

    Agriculture is a key component of anthropogenic land use and land cover changes that influence regional climate. Meanwhile, in addition to socioeconomic drivers, climate is another important factor shaping agricultural land use. In this study, we compare the contributions of climate change and socioeconomic development to potential future changes of agricultural land use in West Africa using a prototype land use projection (LandPro) algorithm. The algorithm is based on a balance between food supply and demand, and accounts for the impact of socioeconomic drivers on the demand side and the impact of climate-induced crop yield changes on the supply side. The impact of human decision-making on land use is explicitly considered through multiple "what-if" scenarios. In the application to West Africa, future crop yield changes were simulated by a process-based crop model driven with future climate projections from a regional climate model, and future changes of food demand is projected using a model for policy analysis of agricultural commodities and trade. Without agricultural intensification, the climate-induced decrease in crop yield together with future increases in food demand is found to cause a significant increase in cropland areas at the expense of forest and grassland by the mid-century. The increase in agricultural land use is primarily climate-driven in the western part of West Africa and socioeconomically driven in the eastern part. Analysis of results from multiple scenarios of crop area allocation suggests that human adaptation characterized by science-informed decision-making can potentially minimize future land use changes in many parts of the region.

  15. Model-Based Geostatistical Mapping of the Prevalence of Onchocerca volvulus in West Africa.

    Directory of Open Access Journals (Sweden)

    Simon J O'Hanlon

    2016-01-01

    Full Text Available The initial endemicity (pre-control prevalence of onchocerciasis has been shown to be an important determinant of the feasibility of elimination by mass ivermectin distribution. We present the first geostatistical map of microfilarial prevalence in the former Onchocerciasis Control Programme in West Africa (OCP before commencement of antivectorial and antiparasitic interventions.Pre-control microfilarial prevalence data from 737 villages across the 11 constituent countries in the OCP epidemiological database were used as ground-truth data. These 737 data points, plus a set of statistically selected environmental covariates, were used in a Bayesian model-based geostatistical (B-MBG approach to generate a continuous surface (at pixel resolution of 5 km x 5km of microfilarial prevalence in West Africa prior to the commencement of the OCP. Uncertainty in model predictions was measured using a suite of validation statistics, performed on bootstrap samples of held-out validation data. The mean Pearson's correlation between observed and estimated prevalence at validation locations was 0.693; the mean prediction error (average difference between observed and estimated values was 0.77%, and the mean absolute prediction error (average magnitude of difference between observed and estimated values was 12.2%. Within OCP boundaries, 17.8 million people were deemed to have been at risk, 7.55 million to have been infected, and mean microfilarial prevalence to have been 45% (range: 2-90% in 1975.This is the first map of initial onchocerciasis prevalence in West Africa using B-MBG. Important environmental predictors of infection prevalence were identified and used in a model out-performing those without spatial random effects or environmental covariates. Results may be compared with recent epidemiological mapping efforts to find areas of persisting transmission. These methods may be extended to areas where data are sparse, and may be used to help inform the

  16. Climate factors play a limited role for past adaptation strategies in West Africa

    DEFF Research Database (Denmark)

    Mertz, Ole; Mbow, Cheikh; Nielsen, Jonas Østergaard;

    2010-01-01

    The Sudano-Sahelian zone of West Africa has experienced recurrent droughts since the mid-1970s and today there is considerable concern for how this region will be able to adapt to future climate change. To develop well targeted adaptation strategies, the relative importance of climate factors...... as drivers of land use and livelihood change need to be better understood. Based on the perceptions of 1249 households in five countries across an annual rainfall gradient of 400-900 mm, we provide an estimate of the relative weight of climate factors as drivers of changes in rural households during the past...

  17. Uses of graminaceous plants as food by man in West Africa

    Directory of Open Access Journals (Sweden)

    M. S. Chuah

    1983-12-01

    Full Text Available The family Gramineae, with over 7 000 species is the fifth largest family in the plant kingdom, and has over the years played a very important role in providing food for man in the form of cereals among which the most important and well-known examples are rice, wheat, maize and others. The principal graminaceous plants in man’s diet in West Africa are rice (Oryza spp.; maize (Zea mays L. and a variety of species belonging to the sorghums and millets (species of Pennisetum, Digitaria and Eleusine. Plants collected in times of famine include species of  Echinochloa, Panicum, Paspalum etc.

  18. Challenges faced by grandparents caring for AIDS orphans in Koster, North West Province of South Africa

    OpenAIRE

    Phetlhu, Deliwe; Watson, Mada

    2014-01-01

    Caring for orphans who have lost their parents due to AIDS, and some of whom are infected, is an enormous challenge. This immense responsibility often resides with the grandparents, who are in most cases sickly and not financially capable to undertake the task. The objectives of this study were to explore and describe challenges faced by such grandparents and their needs while caring for AIDS orphans in Koster, North West province, South Africa. Maslow’s theory of human needs was used as a th...

  19. Optimal control strategies for the spread of Ebola in West Africa

    CERN Document Server

    Rachah, Amira

    2016-01-01

    The spread of Ebola virus in 2014 is unprecedented. The epidemic is still affecting West Africa, exacerbated by extraordinary socioeconomic disadvantages and health system inadequacies. With the aim of understanding, predicting, and control the propagation of the virus in the populations of affected countries, it is crucial to model the dynamics of the virus and study several strategies to control it. In this paper, we present a very simple mathematical model that describes quite well the spread of Ebola. Then, we discuss several strategies for the control of the propagation of this lethal virus into populations, in order to predict the impact of vaccine programmes, treatment, and the impact of educational campaigns.

  20. Agriculture in West Africa in the Twenty-First Century: Climate Change and Impacts Scenarios, and Potential for Adaptation.

    Science.gov (United States)

    Sultan, Benjamin; Gaetani, Marco

    2016-01-01

    West Africa is known to be particularly vulnerable to climate change due to high climate variability, high reliance on rain-fed agriculture, and limited economic and institutional capacity to respond to climate variability and change. In this context, better knowledge of how climate will change in West Africa and how such changes will impact crop productivity is crucial to inform policies that may counteract the adverse effects. This review paper provides a comprehensive overview of climate change impacts on agriculture in West Africa based on the recent scientific literature. West Africa is nowadays experiencing a rapid climate change, characterized by a widespread warming, a recovery of the monsoonal precipitation, and an increase in the occurrence of climate extremes. The observed climate tendencies are also projected to continue in the twenty-first century under moderate and high emission scenarios, although large uncertainties still affect simulations of the future West African climate, especially regarding the summer precipitation. However, despite diverging future projections of the monsoonal rainfall, which is essential for rain-fed agriculture, a robust evidence of yield loss in West Africa emerges. This yield loss is mainly driven by increased mean temperature while potential wetter or drier conditions as well as elevated CO2 concentrations can modulate this effect. Potential for adaptation is illustrated for major crops in West Africa through a selection of studies based on process-based crop models to adjust cropping systems (change in varieties, sowing dates and density, irrigation, fertilizer management) to future climate. Results of the cited studies are crop and region specific and no clear conclusions can be made regarding the most effective adaptation options. Further efforts are needed to improve modeling of the monsoon system and to better quantify the uncertainty in its changes under a warmer climate, in the response of the crops to such

  1. Agriculture in West Africa in the Twenty-First Century: Climate Change and Impacts Scenarios, and Potential for Adaptation.

    Science.gov (United States)

    Sultan, Benjamin; Gaetani, Marco

    2016-01-01

    West Africa is known to be particularly vulnerable to climate change due to high climate variability, high reliance on rain-fed agriculture, and limited economic and institutional capacity to respond to climate variability and change. In this context, better knowledge of how climate will change in West Africa and how such changes will impact crop productivity is crucial to inform policies that may counteract the adverse effects. This review paper provides a comprehensive overview of climate change impacts on agriculture in West Africa based on the recent scientific literature. West Africa is nowadays experiencing a rapid climate change, characterized by a widespread warming, a recovery of the monsoonal precipitation, and an increase in the occurrence of climate extremes. The observed climate tendencies are also projected to continue in the twenty-first century under moderate and high emission scenarios, although large uncertainties still affect simulations of the future West African climate, especially regarding the summer precipitation. However, despite diverging future projections of the monsoonal rainfall, which is essential for rain-fed agriculture, a robust evidence of yield loss in West Africa emerges. This yield loss is mainly driven by increased mean temperature while potential wetter or drier conditions as well as elevated CO2 concentrations can modulate this effect. Potential for adaptation is illustrated for major crops in West Africa through a selection of studies based on process-based crop models to adjust cropping systems (change in varieties, sowing dates and density, irrigation, fertilizer management) to future climate. Results of the cited studies are crop and region specific and no clear conclusions can be made regarding the most effective adaptation options. Further efforts are needed to improve modeling of the monsoon system and to better quantify the uncertainty in its changes under a warmer climate, in the response of the crops to such

  2. Agriculture in West Africa in the Twenty-First Century: Climate Change and Impacts Scenarios, and Potential for Adaptation

    Science.gov (United States)

    Sultan, Benjamin; Gaetani, Marco

    2016-01-01

    West Africa is known to be particularly vulnerable to climate change due to high climate variability, high reliance on rain-fed agriculture, and limited economic and institutional capacity to respond to climate variability and change. In this context, better knowledge of how climate will change in West Africa and how such changes will impact crop productivity is crucial to inform policies that may counteract the adverse effects. This review paper provides a comprehensive overview of climate change impacts on agriculture in West Africa based on the recent scientific literature. West Africa is nowadays experiencing a rapid climate change, characterized by a widespread warming, a recovery of the monsoonal precipitation, and an increase in the occurrence of climate extremes. The observed climate tendencies are also projected to continue in the twenty-first century under moderate and high emission scenarios, although large uncertainties still affect simulations of the future West African climate, especially regarding the summer precipitation. However, despite diverging future projections of the monsoonal rainfall, which is essential for rain-fed agriculture, a robust evidence of yield loss in West Africa emerges. This yield loss is mainly driven by increased mean temperature while potential wetter or drier conditions as well as elevated CO2 concentrations can modulate this effect. Potential for adaptation is illustrated for major crops in West Africa through a selection of studies based on process-based crop models to adjust cropping systems (change in varieties, sowing dates and density, irrigation, fertilizer management) to future climate. Results of the cited studies are crop and region specific and no clear conclusions can be made regarding the most effective adaptation options. Further efforts are needed to improve modeling of the monsoon system and to better quantify the uncertainty in its changes under a warmer climate, in the response of the crops to such

  3. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

    Directory of Open Access Journals (Sweden)

    Leticia Franco

    2011-08-01

    Full Text Available Dengue virus (DENV circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF with thrombocytopenia (13000/µl, a raised hematocrit (32% above baseline and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain.

  4. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

    Science.gov (United States)

    Franco, Leticia; Palacios, Gustavo; Martinez, José Antonio; Vázquez, Ana; Savji, Nazir; De Ory, Fernando; Sanchez-Seco, María Paz; Martín, Dolores; Lipkin, W Ian; Tenorio, Antonio

    2011-08-01

    Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain.

  5. A review of mangrove and coastal ecosystems in West Africa and their possible relationships

    Science.gov (United States)

    John, D. M.; Lawson, G. W.

    1990-11-01

    Mangrove forest, which in West Africa covers an area of over 27 000 km 2 of deltas, estuaries and lagoons, is intimately linked to the offshore coastal ecosystem. Regularly influenced and disturbed by seasonal freshwater and diurnal tidal flooding, it exhibits features of an immature ecosystem, namely low species diversity and high productivity. The excess organic production is exploited by many marine species especially fishes and crustaceans that enter the mangrove environment as juveniles and return to the sea as adults for reproductive purposes. The beneficial effects on marine fisheries of this net energy outflow are at risk from anthropogenic influences causing pollution or destruction of the mangrove ecosystem. Intense interdisciplinary work on this problem is in progress on the lagoons of the Ivory Coast but further research on other parts of the West African mangrove ecosystem, especially on the Niger delta, needs to be undertaken to provide the scientific basis for the proper management of this valuable natural resource.

  6. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

    Science.gov (United States)

    Franco, Leticia; Palacios, Gustavo; Martinez, José Antonio; Vázquez, Ana; Savji, Nazir; De Ory, Fernando; Sanchez-Seco, María Paz; Martín, Dolores; Lipkin, W Ian; Tenorio, Antonio

    2011-08-01

    Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above baseline) and mucosal bleeding in a 27-year-old male returning to Spain in November 2009 after visiting his home country Guinea Bissau. Sylvatic DENV-2 West African lineage was isolated from blood and sera. This is the first case of DHF associated with sylvatic DENV-2 in Africa and the second case worldwide of DHF caused by a sylvatic strain. PMID:21829739

  7. The DACCIWA Project: Dynamics-Aerosol-Chemistry-Cloud interactions in West Africa

    Science.gov (United States)

    Knippertz, Peter

    2014-05-01

    Massive economic and population growth and urbanisation are expected to lead to a tripling of anthropogenic emissions from southern West Africa (SWA) between 2000 and 2030, the impacts of which on human health, ecosystems, food security and the regional climate are largely unknown. An assessment of these impacts is complicated by (a) a superposition with effects of global climate change, (b) the strong dependence of SWA on the sensitive West African monsoon, (c) incomplete scientific understanding of interactions between emissions, clouds, radiation, precipitation and regional circulations and (d) by a lack of observations to advance our understanding and improve predictions. The purpose of this contribution is to introduce the research consortium DACCIWA (Dynamics-Aerosol-Chemistry-Cloud interactions in West Africa), which comprises 16 partners in six European and West African countries. The interdisciplinary DACCIWA team will build on the scientific and logistical foundations established by the African Monsoon Multidisciplinary Analysis (AMMA) project and collaborate closely with operational centres. DACCIWA will receive funding of about M8.75€ from the European Commission as part of Framework Programme 7 from 2015 until 2018. The DACCIWA project will conduct extensive fieldwork in SWA to collect high-quality observations, spanning the entire process chain from surface-based natural and anthropogenic emissions to impacts on health, ecosystems and climate. This will include a major field campaign in summer 2015 with three research aircrafts and two ground-based supersites. Combining the resulting benchmark dataset with a wide range of modelling activities will allow us: (a) to assess all relevant physical and chemical processes, (b) to improve the monitoring of climate and compositional parameters from space, (c) to determine health impacts from air pollution, and (d) to develop the next generation of weather and climate models capable of representing coupled

  8. Robust features of future climate change impacts on sorghum yields in West Africa

    Science.gov (United States)

    Sultan, B.; Guan, K.; Kouressy, M.; Biasutti, M.; Piani, C.; Hammer, G. L.; McLean, G.; Lobell, D. B.

    2014-10-01

    West Africa is highly vulnerable to climate hazards and better quantification and understanding of the impact of climate change on crop yields are urgently needed. Here we provide an assessment of near-term climate change impacts on sorghum yields in West Africa and account for uncertainties both in future climate scenarios and in crop models. Towards this goal, we use simulations of nine bias-corrected CMIP5 climate models and two crop models (SARRA-H and APSIM) to evaluate the robustness of projected crop yield impacts in this area. In broad agreement with the full CMIP5 ensemble, our subset of bias-corrected climate models projects a mean warming of +2.8 °C in the decades of 2031-2060 compared to a baseline of 1961-1990 and a robust change in rainfall in West Africa with less rain in the Western part of the Sahel (Senegal, South-West Mali) and more rain in Central Sahel (Burkina Faso, South-West Niger). Projected rainfall deficits are concentrated in early monsoon season in the Western part of the Sahel while positive rainfall changes are found in late monsoon season all over the Sahel, suggesting a shift in the seasonality of the monsoon. In response to such climate change, but without accounting for direct crop responses to CO2, mean crop yield decreases by about 16-20% and year-to-year variability increases in the Western part of the Sahel, while the eastern domain sees much milder impacts. Such differences in climate and impacts projections between the Western and Eastern parts of the Sahel are highly consistent across the climate and crop models used in this study. We investigate the robustness of impacts for different choices of cultivars, nutrient treatments, and crop responses to CO2. Adverse impacts on mean yield and yield variability are lowest for modern cultivars, as their short and nearly fixed growth cycle appears to be more resilient to the seasonality shift of the monsoon, thus suggesting shorter season varieties could be considered a potential

  9. Propagation of Satelite Rainfall Products uncertainties in hydrological applications : Examples in West-Africa in the framework of the Megha-Tropiques Satellite Mission

    Science.gov (United States)

    Casse, C.; Gosset, M.; Peugeot, C.; Boone, A.; Pedinotti, V.

    2013-12-01

    rainfall products are carried out. A simple method based on probability matching is applied to correct the RT products from their main biases. Several sensitivity studies have also been carried out in the Oueme Basin in Benin, West Africa, one of the instrumented basin used for MT products direct and hydrological validation. The tests highlight the fact that not only total biases but also the distribution of rain rates are key players for explaining the hydrological model sensitivity. (a) TMPAv7 total rainfall in 2010 in West Africa. Solid gray line delimits Niger river catchment, and dotted lines delimit Niger right bank tributary catchments. (b) Observed and simulated discharge at Niamey station. Preliminary results using the SURFEX hydrological model over Niger catchment and different satellite rainfall products as forcing.

  10. Clinical manifestations of Waardenburg syndrome in a male adolescent in Mali, West Africa.

    Science.gov (United States)

    Imperato, Pascal James; Imperato, Gavin H

    2015-02-01

    Waardenburg syndrome (WS) is a genetic disorder of which there are four distinct types. These four types are differentiated by the physical defects which they produce. Presented here is the case of a 13-year-old boy with WS Type I who was observed and physically assessed in Mali, West Africa in 1969. His physical findings included a bright blue coloring to the irises of the eyes, profound sensorineural deafness, mutism, dystopia canthorum (lateral displacement of the inner canthi of the eyes), broad nasal root, bushy eyebrows, and scaphoid deformities of the supraorbital portions of the frontal bone. Because family members were not available for interviews or physical examinations, it was not possible to determine if this patient was suffering from a congenital form of the disorder or from a spontaneous mutation. Given the patient's then location in a remote rural area of Mali where electricity was absent, it was not possible to perform additional diagnostic tests. The patient described here is the first with WS in Mali, West Africa to have been medically observed and evaluated and later documented in the medical literature. A second case of the syndrome in Mali was described in the medical literature in 2011 in an 18-month-old infant who did not have sensorineural hearing loss, but who did have a bilateral cleft lip. An historical overview of WS is presented along with details concerning the characteristics of the four types of the disorder. PMID:25224968

  11. Distance, Borders, and Time: The Diffusion and Permeability of Political Violence in North and West Africa

    DEFF Research Database (Denmark)

    Skillicorn, David; Walther, Olivier; Zheng, Quan;

    This paper explores the spatial and temporal diffusion of political violence in North and West Africa. It does so by endeavoring to represent the mental landscape that lives in the back of a group leader’s mind as he contemplates strategic targeting. We assume that this representation is a combin......This paper explores the spatial and temporal diffusion of political violence in North and West Africa. It does so by endeavoring to represent the mental landscape that lives in the back of a group leader’s mind as he contemplates strategic targeting. We assume that this representation...... is a combination of the physical geography of the target environment, and the mental and physical cost of following a seemingly random pattern of attacks. Focusing on the distance and time between attacks and taking into consideration the transaction costs that state boundaries impose, we wish to understand what...... distance, undirected edges representing borders, and directed edges representing consecutive attacks by the same group at the two endpoints. We analyze the resulting network using novel spectral embedding techniques that are able to account fully for the different types of edges. The result is a “map...

  12. Viral bioterrorism: Learning the lesson of Ebola virus in West Africa 2013-2015.

    Science.gov (United States)

    Cenciarelli, Orlando; Gabbarini, Valentina; Pietropaoli, Stefano; Malizia, Andrea; Tamburrini, Annalaura; Ludovici, Gian Marco; Carestia, Mariachiara; Di Giovanni, Daniele; Sassolini, Alessandro; Palombi, Leonardo; Bellecci, Carlo; Gaudio, Pasquale

    2015-12-01

    Among the potential biological agents suitable as a weapon, Ebola virus represents a major concern. Classified by the CDC as a category A biological agent, Ebola virus causes severe hemorrhagic fever, characterized by high case-fatality rate; to date, no vaccine or approved therapy is available. The EVD epidemic, which broke out in West Africa since the late 2013, has got the issue of the possible use of Ebola virus as biological warfare agent (BWA) to come to the fore once again. In fact, due to its high case-fatality rate, population currently associates this pathogen to a real and tangible threat. Therefore, its use as biological agent by terrorist groups with offensive purpose could have serious repercussions from a psychosocial point of view as well as on closely sanitary level. In this paper, after an initial study of the main characteristics of Ebola virus, its potential as a BWA was evaluated. Furthermore, given the spread of the epidemic in West Africa in 2014 and 2015, the potential dissemination of the virus from an urban setting was evaluated. Finally, it was considered the actual possibility to use this agent as BWA in different scenarios, and the potential effects on one or more nation's stability.

  13. Distance, Borders, and Time: The Diffusion and Permeability of Political Violence in North and West Africa

    CERN Document Server

    Skillicorn, David; Zheng, Quan; Leuprecht, Christian

    2016-01-01

    This paper explores the spatial and temporal diffusion of political violence in North and West Africa. It does so by endeavoring to represent the mental landscape that lives in the back of a group leader's mind as he contemplates strategic targeting. We assume that this representation is a combination of the physical geography of the target environment, and the mental and physical cost of following a seemingly random pattern of attacks. Focusing on the distance and time between attacks and taking into consideration the transaction costs that state boundaries impose, we wish to understand what constrains a group leader to attack at a location other than the one that would seem to yield the greatest overt payoff. By its very nature, the research problem defies the collection of a full set of structural data. Instead, we leverage functional data from the Armed Conflict Location and Event Data project (ACLED) dataset that, inter alia, meticulously catalogues violent extremist incidents in North and West Africa si...

  14. Distribution of HBV genotypes among HBV carriers in Benin:phylogenetic analysis and virological characteristics of HBV genotype E

    Institute of Scientific and Technical Information of China (English)

    Kei Fujiwara; Atsushi Ozasa; Yuko Sakamoto; Isao Arita; Ahmed El-Gohary; Agossou Benoit; Sophie I Ogoundele-Akplogan; Namiko Yoshihara; Ryuzo Ueda; Masashi Mizokami; Yasuhito Tanaka; Etsuro Orito; Tomoyoshi Ohno; Takanobu Kato; Kanji Sugihara; Izumi Hasegawa; Mayumi Sakurai; Kiyoaki Ito

    2005-01-01

    AIM: To determine the distribution of Hepatitis B virus (HBV) genotypes in Benin, and to clarify the virological characteristics of the dominant genotype.METHODS: Among 500 blood donors in Benin, 21 HBsAg-positive donors were enrolled in the study. HBV genotypes were determined by enzyme immunoassay and restriction fragment length polymorphism. Complete genome sequences were determined by PCR and direct sequencing.RESULTS: HBV genotype E (HBV/E) was detected in 20/21 (95.2%), and HBV/A in 1/21 (4.8%). From the age-specific prevalence of HBeAg to anti-HBe seroconversion (SC) in 19 HBV/E subjects, SC was estimated to occur frequently in late teens in HBV/E.The comparison of four complete HBV/E genomes from HBeAg-positive subjects in this study and five HBV/E sequences recruited from the database revealed that HBV/E was distributed throughout West Africa with very low genetic divers ity (nucleotide homology 96.7-99.2%).Based on the sequences in the basic core promoter (BCP)to precore region of the nine HBV/E isolates compared to those of the other genotypes, a nucleotide substitution in the BCP, G1757A, was observed in HBV/E.CONCLUSION: HBV/E is predominant in the Republic of Benin, and SC is estimated to occur in late teens in HBV/E. The specific nucleotide substitution G1757A in BCP, which might influence the virological characteristics,is observed in HBV/E.

  15. Sociocultural aspects of risk to pregnant women during the 2013-2015 multinational Ebola virus outbreak in West Africa.

    Science.gov (United States)

    Strong, Adrienne; Schwartz, David A

    2016-08-01

    Researchers reflect on sociocultural aspects of the Ebola outbreak in West Africa and critically analyze the epidemic's effects on pregnant mothers and their babies. We address structural inequalities contributing to poor maternal health in lower-income countries, while reflecting on how the Ebola outbreak highlights the still-marginalized role of pregnant women. Drawing on prior research in West and East Africa, we discuss health care providers' responses to risk of infection during maternity work under normal circumstances and in times of crisis. We end with recommendations for preventing such detrimental effects on the health of pregnant women in the case of another epidemic. PMID:26985811

  16. Survey of the livestock ticks of the North West province, South Africa

    Directory of Open Access Journals (Sweden)

    Arthur M. Spickett

    2011-02-01

    Full Text Available Ticks, as vectors of disease and damage agents, impact directly and indirectly on the economy of the livestock industry in southern Africa. This study surveyed the occurrence and distribution of ticks infesting livestock across the North West province, South Africa. During three phases in consecutive years, officers of the provincial Veterinary Department collected specimens monthly from livestock hosts at specified sites across the province. Data analysis constituted the fourth phase of the study. A total of 1090 collections from 265 sites yielded 42 566 tick specimens, comprising 22 different tick species (18 ixodids, 4 argasids. The specimens represent all of the major tick vectors of disease that occur in South Africa. The major tick-borne diseases (i.e. heartwater, both African and Asiatic bovine babesiosis and anaplasmosis were found to be prevalent mainly in the north-eastern region of the province, which also displayed the highest tick species diversity. The central region appears transitory to some of the major vectors. Although some tick species were contained within specific regions, others were widespread across the province. Associated serology data show that most herds sampled in areas endemic for babesiosis and anaplasmosis in the north-eastern region are endemically unstable and at risk to these tick-borne diseases should vector control measures become ineffective.

  17. National-level differences in the adoption of environmental health technologies: a cross-border comparison from Benin and Togo.

    Science.gov (United States)

    Wendland, Kelly J; Pattanayak, Subhrendu K; Sills, Erin O

    2015-03-01

    Environmental health problems such as malaria, respiratory infections, diarrhoea and malnutrition pose very high burdens on the poor rural people in much of the tropics. Recent research on key interventions-the adoption and use of relatively cheap and effective environmental health technologies-has focused primarily on the influence of demand-side household-level drivers. Relatively few studies of the promotion and use of these technologies have considered the role of contextual factors such as governance, the enabling environment and national policies because of the challenges of cross-country comparisons. We exploit a natural experimental setting by comparing household adoption across the Benin-Togo national border that splits the Tamberma Valley in West Africa. Households across the border share the same culture, ethnicity, weather, physiographic features, livelihoods and infrastructure; however, they are located in countries at virtually opposite ends of the institutional spectrum of democratic elections, voice and accountability, effective governance and corruption. Binary choice models and rigorous non-parametric matching estimators confirm that households in Benin are more likely than households in Togo to plant soybeans, build improved cookstoves and purchase mosquito nets, ceteris paribus. Although we cannot identify the exact mechanism for the large and significant national-level differences in technology adoption, our findings suggest that contextual institutional factors can be more important than household characteristics for technology adoption. PMID:24436179

  18. Violent Conflicts and Civil Strife in West Africa: Causes, Challenges and Prospects

    Directory of Open Access Journals (Sweden)

    Nancy Annan

    2014-01-01

    Full Text Available The advent of intra-state conflicts or ‘new wars’ in West Africa has brought many of its economies to the brink of collapse, creating humanitarian casualties and concerns. For decades, countries such as Liberia, Sierra Leone, Côte d’Ivoire and Guinea- Bissau were crippled by conflicts and civil strife in which violence and incessant killings were prevalent. While violent conflicts are declining in the sub-region, recent insurgencies in the Sahel region affecting the West African countries of Mali, Niger and Mauritania and low intensity conflicts surging within notably stable countries such as Ghana, Nigeria and Senegal sends alarming signals of the possible re-surfacing of internal and regional violent conflicts. These conflicts are often hinged on several factors including poverty, human rights violations, bad governance and corruption, ethnic marginalization and small arms proliferation. Although many actors including the ECOWAS, civil society and international community have been making efforts, conflicts continue to persist in the sub-region and their resolution is often protracted. This paper posits that the poor understanding of the fundamental causes of West Africa’s violent conflicts and civil strife would likely cause the sub-region to continue experiencing and suffering the brunt of these violent wars.

  19. Evaluation of rainfall retrievals from SEVIRI reflectances over West Africa using TRMM-PR and CMORPH

    Directory of Open Access Journals (Sweden)

    E. L. A. Wolters

    2011-02-01

    Full Text Available This paper describes the evaluation of the KNMI Cloud Physical Properties – Precipitation Properties (CPP-PP algorithm over West Africa. The algorithm combines condensed water path (CWP, cloud phase (CPH, cloud particle effective radius (re, and cloud-top temperature (CTT retrievals from visible, near-infrared and thermal infrared observations of the Spinning Enhanced Visible and Infrared Imager (SEVIRI onboard the Meteosat Second Generation (MSG satellites to estimate rain occurrence frequency and rain rate. For the 2005 and 2006 monsoon seasons, it is investigated whether the CPP-PP algorithm is capable of retrieving rain occurrence frequency and rain rate over West Africa with sufficient accuracy, using Tropical Monsoon Measurement Mission Precipitation Radar (TRMM-PR as reference. As a second goal, it is assessed whether SEVIRI is capable of monitoring the seasonal and daytime evolution of rainfall during the West African monsoon (WAM, using Climate Prediction Center Morphing Technique (CMORPH rainfall observations. The SEVIRI-detected rainfall area agrees well with TRMM-PR, with the areal extent of rainfall by SEVIRI being ~10% larger than from TRMM-PR. The mean retrieved rain rate from CPP-PP is about 8% higher than from TRMM-PR. Examination of the TRMM-PR and CPP-PP cumulative frequency distributions revealed that differences between CPP-PP and TRMM-PR are generally within +/−10%. Relative to the AMMA rain gauge observations, CPP-PP shows very good agreement up to 5 mm h−1. However, at higher rain rates (5–16 mm h−1 CPP-PP overestimates compared to the rain gauges. With respect to the second goal of this paper, it was shown that both the accumulated precipitation and the seasonal progression of rainfall throughout the WAM is in good agreement with CMORPH, although CPP-PP retrieves higher amounts in the coastal region of West Africa. Using latitudinal Hovmüller diagrams, a fair

  20. A Mycobacterial Perspective on Tuberculosis in West Africa: Significant Geographical Variation of M. africanum and Other M. tuberculosis Complex Lineages.

    Directory of Open Access Journals (Sweden)

    Florian Gehre

    2016-03-01

    Full Text Available Phylogenetically distinct Mycobacterium tuberculosis lineages differ in their phenotypes and pathogenicity. Consequently, understanding mycobacterial population structures phylogeographically is essential for design, interpretation and generalizability of clinical trials. Comprehensive efforts are lacking to date to establish the West African mycobacterial population structure on a sub-continental scale, which has diagnostic implications and can inform the design of clinical TB trials.We collated novel and published genotyping (spoligotyping data and classified spoligotypes into mycobacterial lineages/families using TBLineage and Spotclust, followed by phylogeographic analyses using statistics (logistic regression and lineage axis plot analysis in GenGIS, in which a phylogenetic tree constructed in MIRU-VNTRplus was analysed. Combining spoligotyping data from 16 previously published studies with novel data from The Gambia, we obtained a total of 3580 isolates from 12 countries and identified 6 lineages comprising 32 families. By using stringent analytical tools we demonstrate for the first time a significant phylogeographic separation between western and eastern West Africa not only of the two M. africanum (West Africa 1 and 2 but also of several major M. tuberculosis sensu stricto families, such as LAM10 and Haarlem 3. Moreover, in a longitudinal logistic regression analysis for grouped data we showed that M. africanum West Africa 2 remains a persistent health concern.Because of the geographical divide of the mycobacterial populations in West Africa, individual research findings from one country cannot be generalized across the whole region. The unequal geographical family distribution should be considered in placement and design of future clinical trials in West Africa.

  1. The prevalence, awareness, and control of hypertension among workers in West Africa: a systematic review

    Directory of Open Access Journals (Sweden)

    William K. Bosu

    2015-01-01

    Full Text Available Background: Interventions in workplace settings are considered to be cost-effective in preventing cardiovascular diseases. A systematic review was conducted to assess the prevalence of hypertension and the level of awareness and control among workers in West Africa. Design: A systematic search for studies on formal and informal sector workers aged ≥15 years in West Africa published between 1980 and September 2014 was undertaken using the Ovid Medline, Embase, PubMed, and Google Scholar databases. Clinical and obstetric studies and studies that did not report prevalence were excluded. Data on study settings, characteristics of workers, blood pressure (BP levels, prevalence of hypertension, and associated demographic factors were extracted. Results: A total of 45 studies from six countries were identified involving 30,727 formal and informal sector workers. In 40 studies with a common definition of hypertension, the prevalence ranged from 12.0% among automobile garage workers to 68.9% among traditional chiefs. In 15 of these studies, the prevalence exceeded 30%. Typically sedentary workers such as traders, bank workers, civil servants, and chiefs were at high risk. Among health care workers, the prevalence ranged from 17.5 to 37.5%. The prevalence increased with age and was higher among males and workers with higher socio-economic status. Complications of hypertension, co-morbidities, and clustering of risk factors were common. The crude prevalence of hypertension increased progressively from 12.9% in studies published in the 1980s to 34.4% in those published in 2010–2014. The proportion of hypertensives who were previously aware of their diagnosis, were on treatment or had their BP controlled was 19.6–84.0%, 0–79.2%, and 0–12.7%, respectively. Hypertensive subjects, including health workers, rarely checked their BP except when they were ill. Conclusions: There is a high prevalence of hypertension among West Africa's workforce, of which

  2. Tailoring conservation agriculture technologies to West Africa semi-arid zones: Building on traditional local practices for soil restoration

    NARCIS (Netherlands)

    Lahmar, R.; Bationo, B.A.; Lamso, N.D.; Guéro, Y.; Tittonell, P.A.

    2012-01-01

    Low inherent fertility of tropical soils and degradation, nutrient deficiency and water stress are the key factors that hamper rainfed agriculture in semi-arid West Africa. Conservation Agriculture (CA) is currently promoted in the region as a technology to reduce soil degradation, mitigate the effe

  3. Mapping transmission risk of Lassa fever in West Africa: the importance of quality control, sampling bias, and error weighting.

    Directory of Open Access Journals (Sweden)

    A Townsend Peterson

    Full Text Available Lassa fever is a disease that has been reported from sites across West Africa; it is caused by an arenavirus that is hosted by the rodent M. natalensis. Although it is confined to West Africa, and has been documented in detail in some well-studied areas, the details of the distribution of risk of Lassa virus infection remain poorly known at the level of the broader region. In this paper, we explored the effects of certainty of diagnosis, oversampling in well-studied region, and error balance on results of mapping exercises. Each of the three factors assessed in this study had clear and consistent influences on model results, overestimating risk in southern, humid zones in West Africa, and underestimating risk in drier and more northern areas. The final, adjusted risk map indicates broad risk areas across much of West Africa. Although risk maps are increasingly easy to develop from disease occurrence data and raster data sets summarizing aspects of environments and landscapes, this process is highly sensitive to issues of data quality, sampling design, and design of analysis, with macrogeographic implications of each of these issues and the potential for misrepresenting real patterns of risk.

  4. Common challenges in gum arabic production and commercialization in West Africa: a comparative study of Cameroon, Niger and Senegal

    NARCIS (Netherlands)

    Mujawamariya, G.; Madi, O.P.; Zoubeirou, A.M.; Sene, A.; Maisharou, A.; Haese, D' M.F.C.

    2013-01-01

    As gum arabic is widely used in food and non-food industries, demand is high all over the world. Still, smaller production countries in West Africa such as Cameroon, Niger and Senegal seem to have so many difficulties producing and commercializing gum arabic that their market shares have declined si

  5. The mineralogy of global magnetic anomalies. [rock magnetic signatures and MAGSAT geological, and gravity correlations in West Africa

    Science.gov (United States)

    Haggerty, S. E. (Principal Investigator)

    1982-01-01

    Problems with the Curie balance, which severely hindered the acquisition of data, were rectified. Chemical analytical activities are proceeding satisfactorily. The magnetization characteristics of metamorphic suites were analyzed and susceptibility data for a wide range of metamorphic and igneous rocks. These rock magnetic signatures are discussed as well as the relationships between geology, gravity and MAGSAT anomalies of West Africa.

  6. Mapping transmission risk of Lassa fever in West Africa: the importance of quality control, sampling bias, and error weighting.

    Science.gov (United States)

    Peterson, A Townsend; Moses, Lina M; Bausch, Daniel G

    2014-01-01

    Lassa fever is a disease that has been reported from sites across West Africa; it is caused by an arenavirus that is hosted by the rodent M. natalensis. Although it is confined to West Africa, and has been documented in detail in some well-studied areas, the details of the distribution of risk of Lassa virus infection remain poorly known at the level of the broader region. In this paper, we explored the effects of certainty of diagnosis, oversampling in well-studied region, and error balance on results of mapping exercises. Each of the three factors assessed in this study had clear and consistent influences on model results, overestimating risk in southern, humid zones in West Africa, and underestimating risk in drier and more northern areas. The final, adjusted risk map indicates broad risk areas across much of West Africa. Although risk maps are increasingly easy to develop from disease occurrence data and raster data sets summarizing aspects of environments and landscapes, this process is highly sensitive to issues of data quality, sampling design, and design of analysis, with macrogeographic implications of each of these issues and the potential for misrepresenting real patterns of risk. PMID:25105746

  7. Mapping Transmission Risk of Lassa Fever in West Africa: The Importance of Quality Control, Sampling Bias, and Error Weighting

    Science.gov (United States)

    Peterson, A. Townsend; Moses, Lina M.; Bausch, Daniel G.

    2014-01-01

    Lassa fever is a disease that has been reported from sites across West Africa; it is caused by an arenavirus that is hosted by the rodent M. natalensis. Although it is confined to West Africa, and has been documented in detail in some well-studied areas, the details of the distribution of risk of Lassa virus infection remain poorly known at the level of the broader region. In this paper, we explored the effects of certainty of diagnosis, oversampling in well-studied region, and error balance on results of mapping exercises. Each of the three factors assessed in this study had clear and consistent influences on model results, overestimating risk in southern, humid zones in West Africa, and underestimating risk in drier and more northern areas. The final, adjusted risk map indicates broad risk areas across much of West Africa. Although risk maps are increasingly easy to develop from disease occurrence data and raster data sets summarizing aspects of environments and landscapes, this process is highly sensitive to issues of data quality, sampling design, and design of analysis, with macrogeographic implications of each of these issues and the potential for misrepresenting real patterns of risk. PMID:25105746

  8. Systems development in agricultural mechanization with special reference to soil tillage and weed control. A case study for West Africa

    NARCIS (Netherlands)

    Curfs, H.P.F.

    1976-01-01

    IntroductionMechanization in West Africa has been of limited importance and influence for farming and manual labour is the dominant power input. At present only about 0.07 kW per ha is applied, while at least about 0.37 kW is desirable to obtain high yield levels.In this mechanization study a review

  9. Climate change, climate variability and adaptation options in smallholder cropping systems of the Sudano - Sahel region in West Africa

    NARCIS (Netherlands)

    Traore, B.

    2014-01-01

    Key words: crop production, maize, millet, sorghum, cotton, fertilizer, rainfall, temperature, APSIM, Mali,   In the Sudano-Sahelian zone of West Africa (SSWA) agricultural production remains the main source of livelihood for rural communities, providing employment to more than 60 percent of

  10. Critical Limit of Extractable Phosphorous in a Gleysol for Rice Production in the Senegal River Valley of West Africa

    NARCIS (Netherlands)

    Bado, B.V.; Vries, de M.E.; Haefele, S.M.; Marco, M.C.S.; Ndiaye, M.K.

    2008-01-01

    Soil-test correlation and calibration, a useful tool for fertilizer recommendations, has been little used in West Africa. Soils from a long-term fertility experiment have been used to study the relationship between rice yields and soil extractable phosphorus (P) with Bray 1 and Olsen methods. The Ca

  11. The spatial genetic differentiation of the legume pod borer, Maruca vitrata F. (Lepidoptera: Pyralidae) populations in West Africa

    Science.gov (United States)

    The legume pod borer, Maruca vitrata, is an endemic insect pest that causes significant yield loss to the cowpea crop in West Africa, and contributes to food shortages and malnutrition in native human populations. The genetic structure of Maruca vitrata was investigated among five sites from Burkin...

  12. Termite and earthworm abundance and taxonomic richness under long-term conservation soil management in Saria, Burkina Faso, West Africa

    NARCIS (Netherlands)

    Zida, Z.; Ouedraogo, E.; Mando, A.; Stroosnijder, L.

    2011-01-01

    Unsustainable crop and soil management practices are major causes of soil degradation and declining soil biodiversity in West Africa. Identifying soil management practices that favor macrofauna abundance is highly desirable for long-term soil health. This study investigates the effects of long-term

  13. Organic resources and earthworms affect phosphorus availability to sorghum after phosphate rock addition in semi-arid West Africa

    NARCIS (Netherlands)

    Ouédraogo, E.; Brussaard, L.; Mando, A.; Stroosnijder, L.

    2005-01-01

    A field experiment was laid out in Burkina Faso (West Africa) on an Eutric Cambisol to investigate the interaction of organic resource quality and phosphate rock on crop yield and to assess the contribution of earthworms (Millsonia inermis Michaelsen) to P availability after phosphate rock applicati

  14. The effect of temporal variation on inputs and outputs of future-oriented land use systems in West Africa

    NARCIS (Netherlands)

    Hengsdijk, H.; Keulen, van H.

    2002-01-01

    The (semi-) arid area of West Africa is characterized by erratic rainfall that causes highly variable performances of cropping systems. This creates difficulties in strategic decision-making based on future-oriented production systems. In this paper, the degree of variation in inputs and outputs of

  15. Perspectives on West Africa Ebola Virus Disease Outbreak, 2013–2016

    Science.gov (United States)

    Spengler, Jessica R.; Ervin, Elizabeth D.; Towner, Jonathan S.; Rollin, Pierre E.

    2016-01-01

    The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013–2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community’s insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Continued efforts during the outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research. PMID:27070842

  16. Remote sensing of biomass burning in West Africa with NOAA-AVHRR

    International Nuclear Information System (INIS)

    Remote sensing measurements provide a valuable means of determining the extent of burning areas and estimating the overall distribution of the sources in time and space. The Advanced Very High Resolution Radiometer (NOAA-AVHRR) satellite is well adapted to a wide coverage of the large African savanna regions. It is necessary to watch the whole area even at times other then during the dry season, since two consecutive weeks without precipitation may be sufficient to allow the bushes to catch fire. The images examined in this chapter include the whole of West Africa - namely, within latitudes 5 degree and 14 degree N and 1 degree and 11 degree W. The study has been focused on a region that contains part of the Guinea territory, Mali, the Ivory Coast, and Burkina Faso

  17. Mineralogical, crystallographic and morphological characteristics of natural kaolins from the Ivory Coast (West Africa)

    Science.gov (United States)

    Sei, J.; Morato, F.; Kra, G.; Staunton, S.; Quiquampoix, H.; Jumas, J. C.; Olivier-Fourcade, J.

    2006-10-01

    Thirteen clay samples from four deposits in the Ivory Coast (West Africa) were studied using X-ray diffraction, thermogravimetric analysis and chemical analysis. Mineralogical, crystallographic and morphological characteristics of these samples are given. Kaolinite is the principal mineral but other minerals are present in small quantities: illite, quartz, anatase and iron oxides (oxides and oxyhydroxides). The crystallographic, morphological and surface characteristics are influenced by the presence of these impurities. In particular, the presence of iron oxides was associated with reduced structural ordering and thermal stability of kaolinite and increased specific surface area. These clays could be used in the ceramics industry to make tiles and bricks, and also in agronomy as supports for chemical fertilizers or for environmental protection by immobilising potentially toxic waste products.

  18. Development of a Pain Management Protocol for a Paediatric Ward in the Gambia, West Africa

    Directory of Open Access Journals (Sweden)

    Lisa M. Puchalski Ritchie

    2010-01-01

    Full Text Available Despite recent advances in our understanding of paediatric pain and its management, pain continues to be undertreated globally, particularly in children and in low income countries. This article describes the development of a paediatric analgesia and sedation protocol, tailored to the specific setting of the Medical Research Council (MRC paediatric ward in the Gambia, West Africa. An iterative process was used throughout development, with inputs from the medical literature, local providers, and pain experts, incorporated to ensure a safe, effective, and locally appropriate protocol. We demonstrate that evidence-based published guidelines, can and should be adapted to allow for optimal pain management given the resources and capabilities of specific health care settings. It is hoped that the process and protocol described here, will not only help to improve care on the MRC ward, but serve as an example to others working toward improving pain management in similar health care settings.

  19. Perspectives on West Africa Ebola Virus Disease Outbreak, 2013-2016.

    Science.gov (United States)

    Spengler, Jessica R; Ervin, Elizabeth D; Towner, Jonathan S; Rollin, Pierre E; Nichol, Stuart T

    2016-06-01

    The variety of factors that contributed to the initial undetected spread of Ebola virus disease in West Africa during 2013-2016 and the difficulty controlling the outbreak once the etiology was identified highlight priorities for disease prevention, detection, and response. These factors include occurrence in a region recovering from civil instability and lacking experience with Ebola response; inadequate surveillance, recognition of suspected cases, and Ebola diagnosis; mobile populations and extensive urban transmission; and the community's insufficient general understanding about the disease. The magnitude of the outbreak was not attributable to a substantial change of the virus. Continued efforts during the outbreak and in preparation for future outbreak response should involve identifying the reservoir, improving in-country detection and response capacity, conducting survivor studies and supporting survivors, engaging in culturally appropriate public education and risk communication, building productive interagency relationships, and continuing support for basic research. PMID:27070842

  20. Sawah Rice Eco-technology and Actualization of Green Revolution in West Africa: Experience from Nigeria and Ghana

    Institute of Scientific and Technical Information of China (English)

    O. I. OLADELE; T. WAKATSUKI

    2010-01-01

    The development and dissemination of sawah rice eco-technology in Nigeria and Ghana as prerequisites for the actualization of green revolution in West Africa were described. It showed that the neglect of the eco-technology and the overemphasis of the biotechnology have rendered the ineffective transferability of the green revolution process from Asia to Africa. The sawah eco-technology increases yield up to 5 t/hm2 through bunding and the use of inlet and outlet connecting irrigation and drainage, which enhances effective water control and management, improves the efficiency of fertilizer, improves nitrogen fixation by soil microbes and algae, increases the use of wetlands, improves soil organic matter accumulation, suppresses weed growth, and enhances immune mechanism of rice through nutrient supply. The current experience has therefore established that the technology overcomes the constraints that have limited the realization of green revolution in West Africa.

  1. The Response of Environmental Capacity for Malaria Transmission in West Africa to Climate Change

    Science.gov (United States)

    Yamana, T. K.; Eltahir, E. A.

    2011-12-01

    The climate of West Africa is characterized by north-south gradients in temperature and rainfall. Environmental capacity for malaria transmission (e.g. as measured by vectorial capacity) is strongly tied to these two variables; temperature affects the development rate of the malaria parasite, as well as the lifespan of the mosquitoes that transmit the disease, and rainfall is tied to mosquito abundance, as the vector lays its eggs in rain-fed water pools. A change in climate is therefore expected to lead to changes in the distribution of malaria transmission. Current general circulation models agree that the temperature in West Africa is expected to increase by several degrees in the next century. However they predict a wide range of possible rainfall scenarios in the future, from intense drying to significant increases in rainfall (Christensen et al., 2007). The effects these changes will have on environmental capacity for malaria transmission depend on the magnitude and direction of the changes, and on current conditions. For example, malaria transmission will be more sensitive to positive changes in rainfall in dry areas where mosquito populations are currently limited by water availability than in relatively wet areas. Here, we analyze combinations of changes in rainfall and temperature within the ranges predicted by GCMs, and assess the impact these combinations will have on the environmental capacity for malaria transmission. In particular, we identify climate change scenarios that are likely to have the greatest impact on environmental capacity for malaria transmission, as well as geographic "hot spots" where the greatest changes are to be expected. Christensen, J. H., Busuioc, A., & et al. (2007). Regional climate projections. In S. Solomon (Ed.), Climate change 2007: The physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.

  2. Regional assessment of the hydropower potential of rivers in West Africa

    Science.gov (United States)

    Kling, Harald; Stanzel, Philipp; Fuchs, Martin

    2016-04-01

    The 15 countries of the Economic Community of West African States (ECOWAS) face a constant shortage of energy supply, which limits sustained economic growth. Currently there are about 50 operational hydropower plants and about 40 more are under construction or refurbishment. The potential for future hydropower development - especially for small-scale plants in rural areas - is assumed to be large, but exact data are missing. This study supports the energy initiatives of the "ECOWAS Centre for Renewable Energy and Energy Efficiency" (ECREEE) by assessing the hydropower potential of all rivers in West Africa. For more than 500,000 river reaches the hydropower potential was computed from channel slope and mean annual discharge. In large areas there is a lack of discharge observations. Therefore, an annual water balance model was used to simulate discharge. The model domain covers 5 Mio km², including e.g. the Niger, Volta, and Senegal River basins. The model was calibrated with observed data of 410 gauges, using precipitation and potential evapotranspiration data as inputs. Historic variations of observed annual discharge between 1950 and 2010 are simulated well by the model. As hydropower plants are investments with a lifetime of several decades we also assessed possible changes in future discharge due to climate change. To this end the water balance model was driven with bias-corrected climate projections of 15 Regional Climate Models for two emission scenarios of the CORDEX-Africa ensemble. The simulation results for the river network were up-scaled to sub-areas and national summaries. This information gives a regional quantification of the hydropower potential, expected climate change impacts, as well as a regional classification for general suitability (or non-suitability) of hydropower plant size - from small-scale to large projects.

  3. Climatic and Human Influence on Tropical Forest Degradation in West Africa

    Science.gov (United States)

    Liu, Z., Sr.; Wimberly, M. C.; Dwomoh, F. K.

    2015-12-01

    The Upper Guinean Forests of West Africa encompass one of most fragmented and endangered tropical forest ecosystems on earth. However, relatively little is known about the extent and causes of forest degradation in this heavily human affected region. We used the tasseled cap wetness (TCW) index to detect forest degradation using dry-season imagery from 2001 to 2015. TCW was calculated from MODIS (or Moderate Resolution Imaging Spectroradiometer) Nadir BRDF-Adjusted Reflectance (NBAR) at 500 meter resolution. The TCW index was compared with field data and high-resolution imagery and was found to have a strong relationship with different level of forest degradation, with lower TCW index values indicating higher levels of degradation. Mann-Kendall tests were used to detect the monotonic decreases in TCW index. Results indicated that about 12.9% of tropical forest in West Africa has been degraded during past 15 years, and most of these areas were located in isolated forest patches and on the periphery of intact forest. The boosted regression tree (BRT) method was then used to assess the influence of climate and human influence on forest degradation. BRT analysis indicated that climatic variations, human activities, and their interactions were important contributors to forest degradation. Major drivers of forest degradation included distance to cropland, rainfall trend, and rate of population growth.. Our results show that times series of coarse-resolution MODIS imagery can be used for broad-scale assessment of tropical forest degradation, and human activities need to be taken into account when assessing potential forest responses to climate change in this region.

  4. Accuracy of individual rapid tests for serodiagnosis of gambiense sleeping sickness in West Africa.

    Directory of Open Access Journals (Sweden)

    Vincent Jamonneau

    2015-02-01

    Full Text Available Individual rapid tests for serodiagnosis (RDT of human African trypanosomiasis (HAT are particularly suited for passive screening and surveillance. However, so far, no large scale evaluation of RDTs has been performed for diagnosis of Trypanosoma brucei gambiense HAT in West Africa. The objective of this study was to assess the diagnostic accuracy of 2 commercial HAT-RDTs on stored plasma samples from West Africa.SD Bioline HAT and HAT Sero-K-Set were performed on 722 plasma samples originating from Guinea and Côte d'Ivoire, including 231 parasitologically confirmed HAT patients, 257 healthy controls, and 234 unconfirmed individuals whose blood tested antibody positive in the card agglutination test but negative by parasitological tests. Immune trypanolysis was performed as a reference test for trypanosome specific antibody presence. Sensitivities in HAT patients were respectively 99.6% for SD Bioline HAT, and 99.1% for HAT Sero-K-Set, specificities in healthy controls were respectively 87.9% and 88.3%. Considering combined positivity in both RDTs, increased the specificity significantly (p ≤ 0.0003 to 93.4%, while 98.7% sensitivity was maintained. Specificities in controls were 98.7-99.6% for the combination of one or two RDTs with trypanolysis, maintaining a sensitivity of at least 98.1%.The observed specificity of the single RDTs was relatively low. Serial application of SD Bioline HAT and HAT Sero-K-Set might offer superior specificity compared to a single RDT, maintaining high sensitivity. The combination of one or two RDTs with trypanolysis seems promising for HAT surveillance.

  5. New evidence for hybrid zones of forest and savanna elephants in Central and West Africa.

    Science.gov (United States)

    Mondol, Samrat; Moltke, Ida; Hart, John; Keigwin, Michael; Brown, Lisa; Stephens, Matthew; Wasser, Samuel K

    2015-12-01

    The African elephant consists of forest and savanna subspecies. Both subspecies are highly endangered due to severe poaching and habitat loss, and knowledge of their population structure is vital to their conservation. Previous studies have demonstrated marked genetic and morphological differences between forest and savanna elephants, and despite extensive sampling, genetic evidence of hybridization between them has been restricted largely to a few hybrids in the Garamba region of northeastern Democratic Republic of Congo (DRC). Here, we present new genetic data on hybridization from previously unsampled areas of Africa. Novel statistical methods applied to these data identify 46 hybrid samples--many more than have been previously identified--only two of which are from the Garamba region. The remaining 44 are from three other geographically distinct locations: a major hybrid zone along the border of the DRC and Uganda, a second potential hybrid zone in Central African Republic and a smaller fraction of hybrids in the Pendjari-Arli complex of West Africa. Most of the hybrids show evidence of interbreeding over more than one generation, demonstrating that hybrids are fertile. Mitochondrial and Y chromosome data demonstrate that the hybridization is bidirectional, involving males and females from both subspecies. We hypothesize that the hybrid zones may have been facilitated by poaching and habitat modification. The localized geography and rarity of hybrid zones, their possible facilitation from human pressures, and the high divergence and genetic distinctness of forest and savanna elephants throughout their ranges, are consistent with calls for separate species classification. PMID:26577954

  6. New evidence for hybrid zones of forest and savanna elephants in Central and West Africa.

    Science.gov (United States)

    Mondol, Samrat; Moltke, Ida; Hart, John; Keigwin, Michael; Brown, Lisa; Stephens, Matthew; Wasser, Samuel K

    2015-12-01

    The African elephant consists of forest and savanna subspecies. Both subspecies are highly endangered due to severe poaching and habitat loss, and knowledge of their population structure is vital to their conservation. Previous studies have demonstrated marked genetic and morphological differences between forest and savanna elephants, and despite extensive sampling, genetic evidence of hybridization between them has been restricted largely to a few hybrids in the Garamba region of northeastern Democratic Republic of Congo (DRC). Here, we present new genetic data on hybridization from previously unsampled areas of Africa. Novel statistical methods applied to these data identify 46 hybrid samples--many more than have been previously identified--only two of which are from the Garamba region. The remaining 44 are from three other geographically distinct locations: a major hybrid zone along the border of the DRC and Uganda, a second potential hybrid zone in Central African Republic and a smaller fraction of hybrids in the Pendjari-Arli complex of West Africa. Most of the hybrids show evidence of interbreeding over more than one generation, demonstrating that hybrids are fertile. Mitochondrial and Y chromosome data demonstrate that the hybridization is bidirectional, involving males and females from both subspecies. We hypothesize that the hybrid zones may have been facilitated by poaching and habitat modification. The localized geography and rarity of hybrid zones, their possible facilitation from human pressures, and the high divergence and genetic distinctness of forest and savanna elephants throughout their ranges, are consistent with calls for separate species classification.

  7. West Africa - a safe haven for frogs? A sub-continental assessment of the chytrid fungus (Batrachochytrium dendrobatidis.

    Directory of Open Access Journals (Sweden)

    Johannes Penner

    Full Text Available A putative driver of global amphibian decline is the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd. While Bd has been documented across continental Africa, its distribution in West Africa remains ambiguous. We tested 793 West African amphibians (one caecilian and 61 anuran species for the presence of Bd. The samples originated from seven West African countries - Bénin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Liberia, Sierra Leone - and were collected from a variety of habitats, ranging from lowland rainforests to montane forests, montane grasslands to humid and dry lowland savannahs. The species investigated comprised various life-history strategies, but we focused particularly on aquatic and riparian species. We used diagnostic PCR to screen 656 specimen swabs and histology to analyse 137 specimen toe tips. All samples tested negative for Bd, including a widespread habitat generalist Hoplobatrachus occipitalis which is intensively traded on the West African food market and thus could be a potential dispersal agent for Bd. Continental fine-grained (30 arc seconds environmental niche models suggest that Bd should have a broad distribution across West Africa that includes most of the regions and habitats that we surveyed. The surprising apparent absence of Bd in West Africa indicates that the Dahomey Gap may have acted as a natural barrier. Herein we highlight the importance of this Bd-free region of the African continent - especially for the long-term conservation of several threatened species depending on fast flowing forest streams (Conraua alleni ("Vulnerable" and Petropedetes natator ("Near Threatened" as well as the "Critically Endangered" viviparous toad endemic to the montane grasslands of Mount Nimba (Nimbaphrynoides occidentalis.

  8. A GCM Study of Responses of the Atmospheric Water Cycle of West Africa and the Atlantic to Saharan Dust Radiative Forcing

    Science.gov (United States)

    Lau, K. M.; Kim, K. M.; Sud, Y. C.; Walker, G. K.

    2009-01-01

    The responses of the atmospheric water cycle and climate of West Africa and the Atlantic to radiative forcing of Saharan dust are studied using the NASA finite volume general circulation model (fvGCM), coupled to a mixed layer ocean. We find evidence of an "elevated heat pump" (EHP) mechanism that underlines the responses of the atmospheric water cycle to dust forcing as follow. During the boreal summerr, as a result of large-scale atmospheric feedback triggered by absorbing dust aerosols, rainfall and cloudiness are ehanIed over the West Africa/Eastern Atlantic ITCZ, and suppressed over the West Atlantic and Caribbean region. Shortwave radiation absorption by dust warms the atmosphere and cools the surface, while longwave has the opposite response. The elevated dust layer warms the air over West Africa and the eastern Atlantic. As the warm air rises, it spawns a large-scale onshore flow carrying the moist air from the eastern Atlantic and the Gulf of Guinea. The onshore flow in turn enhances the deep convection over West Africa land, and the eastern Atlantic. The condensation heating associated with the ensuing deep convection drives and maintains an anomalous large-scale east-west overturning circulation with rising motion over West Africa/eastern Atlantic, and sinking motion over the Caribbean region. The response also includes a strengthening of the West African monsoon, manifested in a northward shift of the West Africa precipitation over land, increased low-level westerlies flow over West Africa at the southern edge of the dust layer, and a near surface westerly jet underneath the dust layer overr the Sahara. The dust radiative forcing also leads to significant changes in surface energy fluxes, resulting in cooling of the West African land and the eastern Atlantic, and warming in the West Atlantic and Caribbean. The EHP effect is most effective for moderate to highly absorbing dusts, and becomes minimized for reflecting dust with single scattering albedo at0

  9. Probabilistic Impact Assessment of Domestic Rainwater Harvesting in Urban Slums: West Africa Case Study

    Science.gov (United States)

    Cowden, J. R.; Watkins, D. W.; Mihelcic, J. R.; Fry, L. M.

    2007-12-01

    Urban populations now exceed rural populations worldwide, creating unique challenges in providing basic services, especially in developing countries where informal or illegal settlements grow in peri-urban areas. West Africa is an acute example of the problems created by rapid urban growth, with high levels of urban poverty and low water and sanitation access rates. Although considerable effort has been made in providing improved water access and urban services to slum communities, research indicates that clean water access rates are not keeping up with urbanization rates in several areas of the world and that rapidly growing slum communities are beginning to overwhelm many prior water improvements projects. In the face of these challenges, domestic rainwater harvesting is proposed as a technologically appropriate and economically viable option for enhancing water supplies to urban slum households. However, assessing the reliability, potential health impacts, and overall cost-effectiveness of these systems on a regional level is difficult for several reasons. First, long daily rainfall records are not readily available in much of the developing world, including many regions of sub-Saharan Africa. Second, significant uncertainties exist in the relevant cost, water use, and health data. Third, to estimate the potential future impacts at the regional scale, various global change scenarios should be investigated. Finally, in addition to these technical challenges, there is also a need to develop relatively simple and transparent assessment methods for informing policy makers. A procedure is presented for assessment of domestic rainwater harvesting systems using a combination of scenario, sensitivity, and trade-off analyses. Using data from West Africa, simple stochastic weather models are developed to generate rainfall sequences for the region, which are then used to estimate the reliability of providing a range of per capita water supplies. Next, a procedure is

  10. Vulnerability to climate change of cocoa in West Africa: Patterns, opportunities and limits to adaptation.

    Science.gov (United States)

    Schroth, Götz; Läderach, Peter; Martinez-Valle, Armando Isaac; Bunn, Christian; Jassogne, Laurence

    2016-06-15

    The West African cocoa belt, reaching from Sierra Leone to southern Cameroon, is the origin of about 70% of the world's cocoa (Theobroma cacao), which in turn is the basis of the livelihoods of about two million farmers. We analyze cocoa's vulnerability to climate change in the West African cocoa belt, based on climate projections for the 2050s of 19 Global Circulation Models under the Intergovernmental Panel on Climate Change intermediate emissions scenario RCP 6.0. We use a combination of a statistical model of climatic suitability (Maxent) and the analysis of individual, potentially limiting climate variables. We find that: 1) contrary to expectation, maximum dry season temperatures are projected to become as or more limiting for cocoa as dry season water availability; 2) to reduce the vulnerability of cocoa to excessive dry season temperatures, the systematic use of adaptation strategies like shade trees in cocoa farms will be necessary, in reversal of the current trend of shade reduction; 3) there is a strong differentiation of climate vulnerability within the cocoa belt, with the most vulnerable areas near the forest-savanna transition in Nigeria and eastern Côte d'Ivoire, and the least vulnerable areas in the southern parts of Cameroon, Ghana, Côte d'Ivoire and Liberia; 4) this spatial differentiation of climate vulnerability may lead to future shifts in cocoa production within the region, with the opportunity of partially compensating losses and gains, but also the risk of local production expansion leading to new deforestation. We conclude that adaptation strategies for cocoa in West Africa need to focus at several levels, from the consideration of tolerance to high temperatures in cocoa breeding programs, the promotion of shade trees in cocoa farms, to policies incentivizing the intensification of cocoa production on existing farms where future climate conditions permit and the establishment of new farms in already deforested areas. PMID:26974571

  11. Vulnerability to climate change of cocoa in West Africa: Patterns, opportunities and limits to adaptation.

    Science.gov (United States)

    Schroth, Götz; Läderach, Peter; Martinez-Valle, Armando Isaac; Bunn, Christian; Jassogne, Laurence

    2016-06-15

    The West African cocoa belt, reaching from Sierra Leone to southern Cameroon, is the origin of about 70% of the world's cocoa (Theobroma cacao), which in turn is the basis of the livelihoods of about two million farmers. We analyze cocoa's vulnerability to climate change in the West African cocoa belt, based on climate projections for the 2050s of 19 Global Circulation Models under the Intergovernmental Panel on Climate Change intermediate emissions scenario RCP 6.0. We use a combination of a statistical model of climatic suitability (Maxent) and the analysis of individual, potentially limiting climate variables. We find that: 1) contrary to expectation, maximum dry season temperatures are projected to become as or more limiting for cocoa as dry season water availability; 2) to reduce the vulnerability of cocoa to excessive dry season temperatures, the systematic use of adaptation strategies like shade trees in cocoa farms will be necessary, in reversal of the current trend of shade reduction; 3) there is a strong differentiation of climate vulnerability within the cocoa belt, with the most vulnerable areas near the forest-savanna transition in Nigeria and eastern Côte d'Ivoire, and the least vulnerable areas in the southern parts of Cameroon, Ghana, Côte d'Ivoire and Liberia; 4) this spatial differentiation of climate vulnerability may lead to future shifts in cocoa production within the region, with the opportunity of partially compensating losses and gains, but also the risk of local production expansion leading to new deforestation. We conclude that adaptation strategies for cocoa in West Africa need to focus at several levels, from the consideration of tolerance to high temperatures in cocoa breeding programs, the promotion of shade trees in cocoa farms, to policies incentivizing the intensification of cocoa production on existing farms where future climate conditions permit and the establishment of new farms in already deforested areas.

  12. Genetic structure of the population of Cabo Verde (west Africa): evidence of substantial European admixture.

    Science.gov (United States)

    Parra, E J; Ribeiro, J C; Caeiro, J L; Riveiro, A

    1995-08-01

    The population of Cabo Verde was founded in the fifteenth century (1462), on the basis of slaves brought from the West African coast and a few Europeans, mainly from Portugal. The polymorphism of six red cell enzymes (ADA, AK1, ALAD, ESD, GLO1, and PGD) and ten plasma proteins (AHSG, BF, F13A, F13B, GC, HP, ORM, PLG, TBG, and TF) was studied in a sample of 268 individuals from Cabo Verde (West Africa). There is no statistical evidence of genetic heterogeneity between the two groups of islands which constitute the archipelago, Barlavento and Sotavento. The gene frequency distribution observed in Cabo Verde differs, in many markers, from that of West African populations, suggesting an important European influence. The proportion of Caucasian genes in the population of Cabo Verde has been calculated to be M = 0.3634 +/- 0.0510, and the considerable dispersion of the locus-specific admixture estimates seems to indicate random drift has also played a role in the evolution of the allele frequencies in the archipelago. Partition of the variance of the mean estimate in evolutionary and sampling variance shows the evolutionary variance is more than ten times higher than the sampling variance. When dendrograms are constructed on the basis of different genetic distances, the population of Cabo Verde clusters with Afro-Americans, forming a different group from the populations of the African continent. This is interpreted as a consequence of the importance of Caucasian admixture both in Afro-Americans and in the population of Cabo Verde. PMID:7485435

  13. Extensive nitrogen loss from permeable sediments off North-West Africa

    Science.gov (United States)

    Sokoll, Sarah; Lavik, Gaute; Sommer, Stefan; Goldhammer, Tobias; Kuypers, Marcel M. M.; Holtappels, Moritz

    2016-04-01

    The upwelling area off North-West Africa is characterized by high export production, high nitrate and low oxygen concentration in bottom waters. The underlying sediment consists of sands that cover most of the continental shelf. Due to their permeability sands allow for fast advective pore water transport and can exhibit high rates of nitrogen (N) loss via denitrification as reported for anthropogenically eutrophied regions. However, N loss from sands underlying naturally eutrophied waters is not well studied, and in particular, N loss from the North-West African shelf is poorly constrained. During two research cruises in April/May 2010/2011, sediment was sampled along the North-West African shelf and volumetric denitrification rates were measured in sediment layers down to 8 cm depth using slurry incubations with 15N-labeled nitrate. Areal N loss was calculated by integrating volumetric rates down to the nitrate penetration depth derived from pore water profiles. Areal N loss was neither correlated with water depth nor with bottom water concentrations of nitrate and oxygen but was strongly dependent on sediment grain size and permeability. The derived empirical relation between benthic N loss and grains size suggests that pore water advection is an important regulating parameter for benthic denitrification in sands and further allowed extrapolating rates to an area of 53,000 km2 using detailed sediment maps. Denitrification from this region amounts to 995 kt yr-1 (average 3.6 mmol m-2 d-1) which is 4 times higher than previous estimates based on diffusive pore water transport. Sandy sediments cover 50-60% of the continental shelf and thus may contribute significantly to the global benthic N loss.

  14. [An approach to food consumption in an urban environment. The case of west Africa].

    Science.gov (United States)

    Ag Bendech, M; Gerbouin-Rerolle, P; Chauliac, M; Malvy, D

    1996-01-01

    West Africa has undergone rapid economic and political changes during the last 20 years. After the failure of economic policies implemented since independence, programs for structural adjustment have strongly influenced the economy. Food problems affect each country differently. The Sahel has experienced food shortages and starvation whereas in forested countries the food supply has remained stable. Nevertheless, food policies have not succeeded in contributing to urban and rural development. The rate of urbanization in west Africa is generally low but the rate of urban population growth is particularly high, much more than the growth rates of industry and infrastructure. Although metropolitan areas are affected by poverty, they offer more hope and opportunities than rural areas. Urban markets have expanded and diversified as social differences have also increased and contributed to changes in consumption structure. Urban growth has contributed to the increase of imported food: this is indicated by both the strong dependency and the change of food habits towards western food patterns. Recently however, west African urban dwellers are still preferring local items if they are affordable. When imported products are used, they are integrated within a stable meal plan consisting of a single dish with a base and a sauce, which is typical of African food preparation. Surveys of consumption-budgets are still only available on a national scale. These can provide accurate information about food consumption patterns of families, particularly for significant trends. However, they do not provide information about the dynamics of food consumption, neither for urban areas or the individual. Now a significant proportion of individual food consumption occurs outside of the home, mainly with food provided by street vendors. This new consumption habit is a response to the urban food crisis. Consumption of street-vendor-food comprises one component but this cannot be dissociated from

  15. The nutrition and health impact of cash cropping in west Africa: a historical perspective.

    Science.gov (United States)

    Brun, T A

    1991-01-01

    The impact of cash cropping in West Africa cannot be isolated from its social and historical background. Among the many changes brought to West African economies by cash cropping since the beginning of the century, the present document shows how the extension of trade with European merchants and colonizers created new sets of values and criteria for wealth. Food crops gradually lost their prominent cultural and economics roles to the benefit of export crops or goods. Traditional systems of agricultural production were profoundly disrupted by military actions. They imposed colonial rule and control of trade of tropical crops and goods. Forced labor and compulsory (poorly paid) work assignments were instituted for private and public enterprises: construction of roads, railways, public buildings and plantations. The main justification was the need for cheap labor to cultivate, transport and build roads for the extraction of raw materials. This in turn caused massive migrations from countries such as Burkina Faso (Upper Volta) to Ivory Coast. Cash cropping made systematic collection of taxes possible. An imposition on a per capita basis became the rule and the major incentive of small farmers to engage in commercial farming. Cash cropping made also possible extensive monetarization of West Africa. This results in both favorable and unfavorable effects on the quality of the diet. In profoundly disrupted traditional societies, the diffusion of new consumption patterns was easier and faster. It led to massive food imports of wheat, rice, sugar, alcohol, etc. Cash cropping was (and still is) practiced as a 'mining' agriculture, exhausting soils and deteriorating their fertility for extended periods of time. In the Sudanian and Sahelian zones cash cropping conflicted with the cultivation of grains because peak demands for labor were similar. Therefore, millet and sorghum production declined. Cash cropping was developed in response to the need of European economies for

  16. The nutrition and health impact of cash cropping in west Africa: a historical perspective.

    Science.gov (United States)

    Brun, T A

    1991-01-01

    The impact of cash cropping in West Africa cannot be isolated from its social and historical background. Among the many changes brought to West African economies by cash cropping since the beginning of the century, the present document shows how the extension of trade with European merchants and colonizers created new sets of values and criteria for wealth. Food crops gradually lost their prominent cultural and economics roles to the benefit of export crops or goods. Traditional systems of agricultural production were profoundly disrupted by military actions. They imposed colonial rule and control of trade of tropical crops and goods. Forced labor and compulsory (poorly paid) work assignments were instituted for private and public enterprises: construction of roads, railways, public buildings and plantations. The main justification was the need for cheap labor to cultivate, transport and build roads for the extraction of raw materials. This in turn caused massive migrations from countries such as Burkina Faso (Upper Volta) to Ivory Coast. Cash cropping made systematic collection of taxes possible. An imposition on a per capita basis became the rule and the major incentive of small farmers to engage in commercial farming. Cash cropping made also possible extensive monetarization of West Africa. This results in both favorable and unfavorable effects on the quality of the diet. In profoundly disrupted traditional societies, the diffusion of new consumption patterns was easier and faster. It led to massive food imports of wheat, rice, sugar, alcohol, etc. Cash cropping was (and still is) practiced as a 'mining' agriculture, exhausting soils and deteriorating their fertility for extended periods of time. In the Sudanian and Sahelian zones cash cropping conflicted with the cultivation of grains because peak demands for labor were similar. Therefore, millet and sorghum production declined. Cash cropping was developed in response to the need of European economies for

  17. Isoprene emissions modelling for West Africa: MEGAN model evaluation and sensitivity analysis

    Directory of Open Access Journals (Sweden)

    J. Ferreira

    2010-09-01

    Full Text Available Isoprene emissions are the largest source of reactive carbon to the atmosphere, with the tropics being a major source region. These natural emissions are expected to change with changing climate and human impact on land use. As part of the African Monsoon Multidisciplinary Analyses (AMMA project the Model of Emissions of Gases and Aerosols from Nature (MEGAN has been used to estimate the spatial and temporal distribution of isoprene emissions over the West African region. During the AMMA field campaign, carried out in July and August 2006, isoprene mixing ratios were measured on board the FAAM BAe-146 aircraft. These data have been used to make a qualitative evaluation of the model performance.

    MEGAN was firstly applied to a large area covering much of West Africa from the Gulf of Guinea in the south to the desert in the north and was able to capture the large scale spatial distribution of isoprene emissions as inferred from the observed isoprene mixing ratios. In particular the model captures the transition from the forested area in the south to the bare soils in the north, but some discrepancies have been identified over the bare soil, mainly due to the emission factors used. Sensitivity analyses were performed to assess the model response to changes in driving parameters, namely Leaf Area Index (LAI, Emission Factors (EF, temperature and solar radiation.

    A high resolution simulation was made of a limited area south of Niamey, Niger, where the higher concentrations of isoprene were observed. This is used to evaluate the model's ability to simulate smaller scale spatial features and to examine the influence of the driving parameters on an hourly basis through a case study of a flight on 17 August 2006.

    This study highlights the complex interactions between land surface processes and the meteorological dynamics and chemical composition of the PBL. This has implications for quantifying the impact of biogenic emissions

  18. Microbiological and physicochemical characterization of shea butter sold on Benin markets

    NARCIS (Netherlands)

    Honfo, G.F.; Hell, K.; Akissoe, N.H.; Linnemann, A.R.; Coulibaly, O.

    2012-01-01

    Shea butter, a fat from the nuts of shea tree, is of great nutritional and commercial value for local communities of Africa. The sanitary and physicochemical qualities of shea butter sold in Benin markets are unknown. This study assesses the quality characteristics of 54 samples of shea butter colle

  19. South Atlantic continental margins of Africa: a comparison of the tectonic vs climate interplay on the evolution of equatorial west Africa and SW Africa margins

    CERN Document Server

    Seranne, M; Seranne, Michel; Anka, Zahie

    2005-01-01

    The comparative review of 2 representative segments of Africa continental margin: the equatorial western Africa and the SW Africa margins, helps in analysing the main controlling factors on their development. Early Cretaceous active rifting S of the Walvis Ridge resulted in the formation of the SW Africa volcanic margin. The non-volcanic rifting N of the Walvis ridge, led to the formation of the equatorial western Africa margin, with thick and extensive, synrift basins. Regressive erosion of SW Africa prominent shoulder uplift accounts for high clastic sedimentation rate in Late Cretaceous - Eocene, while dominant carbonate production on equatorial western Africa shelf suggests little erosion of a low hinterland. The early Oligocene climate change had contrasted response in both margins. Emplacement of the Congo deep-sea fan reflects increased erosion in equatorial Africa, under the influence of wet climate, whereas establishment of an arid climate over SW Africa induced a drastic decrease of denudation, and ...

  20. WJH 6th Anniversary Special Issues(2): Hepatocellular carcinoma Problem of hepatocellular carcinoma in West Africa

    Institute of Scientific and Technical Information of China (English)

    Nimzing; G; Ladep; Olufunmilayo; A; Lesi; Pantong; Mark; Maud; Lemoine; Charles; Onyekwere; Mary; Afihene; Mary; ME; Crossey; Simon; D; Taylor-Robinson

    2014-01-01

    The incidence of hepatocellular carcinoma(HCC) isknown to be high in West Africa with an approximateyearly mortality rate of 200000. Several factors are responsible for this. Early acquisition of risk factors; with vertical or horizontal transmission of hepatitis B(HBV), environmental food contaminants(aflatoxins), poor management of predisposing risk factors and poorlymanaged strategies for health delivery. There has been a low uptake of childhood immunisation for hepatitis B in many West African countries. Owing to late presentations, most sufferers of HCC die within weeks of their diagnosis. Highlighted reasons for the specific disease pattern of HCC in West Africa include:(1) high rate of risk factors;(2) failure to identify at risk populations;(3) lack of effective treatment; and(4) scarce resources for timely diagnosis. This is contrasted to the developed world, which generally has sufficient resources to detect cases early for curative treatment. Provision of palliative care for HCC patients is limited by availability and affordability of potent analgesics. Regional efforts, as well as collaborative networking activities hold promise that could change the epidemiology of HCC in West Africa.

  1. Slave trade and hepatitis B virus genotypes and subgenotypes in Haiti and Africa.

    Science.gov (United States)

    Andernach, Iris E; Nolte, Claudine; Pape, Jean W; Muller, Claude P

    2009-08-01

    In Haiti, >90% of the population descended from African slaves. Of 7,147 Haitian pregnant women sampled, 44% of hepatitis B virus (HBV) infections were caused by genotype A1, which today is found mainly in eastern Africa. Twenty percent belong to a rare subgenotype, A5, which has been found only in the former Bight of Benin, a former primary slave trading post. Haitian A subgenotypes appear to have separated early from the African subgenotypes; the most prevalent genotype and subgenotype in West Africa today (E and A3, respectively) are rare in Haiti. This difference indicates that the dominant subgenotypes in Africa emerged in the general population only after the slave trade and explains the low genetic diversity of genotype E. The high prevalence of HBV genotype E in much of Africa further suggests that HBV hyperendemicity is a recent phenomenon, probably resulting from extensive use of unsafe needles. PMID:19751583

  2. Slave Trade and Hepatitis B Virus Genotypes and Subgenotypes in Haiti and Africa

    Science.gov (United States)

    Andernach, Iris E.; Nolte, Claudine; Pape, Jean W.

    2009-01-01

    In Haiti, >90% of the population descended from African slaves. Of 7,147 Haitian pregnant women sampled, 44% of hepatitis B virus (HBV) infections were caused by genotype A1, which today is found mainly in eastern Africa. Twenty percent belong to a rare subgenotype, A5, which has been found only in the former Bight of Benin, a former primary slave trading post. Haitian A subgenotypes appear to have separated early from the African subgenotypes; the most prevalent genotype and subgenotype in West Africa today (E and A3, respectively) are rare in Haiti. This difference indicates that the dominant subgenotypes in Africa emerged in the general population only after the slave trade and explains the low genetic diversity of genotype E. The high prevalence of HBV genotype E in much of Africa further suggests that HBV hyperendemicity is a recent phenomenon, probably resulting from extensive use of unsafe needles. PMID:19751583

  3. Three and half million year vegetation history of South West Africa and its implications for human evolution

    Science.gov (United States)

    Maslin, M. A.; Pancost, R. D.

    2010-12-01

    Ocean Drilling Program Site 1085 provides a continuous marine sediment record off South West Africa for at least the last three and half million years. The n-alkane carbon isotope record from this site records past vegetation and provides an indication of the moisture availability of SW Africa over this time period. We compared the n-alkane carbon isotope record with the soil carbonate carbon isotope records of East Africa to better understand the vegetation dynamics of Africa over the Plio-Pleistocene. In SW Africa very little variation, and no trend, is observed in the n-alkane carbon isotope record over 3 million years, suggesting stable long-term conditions despite large changes in East African tectonics and global climate. Slightly higher n-alkane carbon isotope values occur between 3.5 and 2.7 Ma suggesting slightly drier conditions than today. Between 2.5 and 2.7 Ma there is a shift to more negative n-alkane carbon isotope values suggesting slightly wetter conditions during a ~0.2 Ma episode that coincides with the intensification of Northern Hemisphere Glaciation (iNHG). From 2.5 to 0.4 Ma the n-alkane carbon isotope values are very consistent, varying by less than ±0.5 per mil and suggesting little or no long-term change in the moisture availability of South West Africa over the last 2.5 million years. This is in marked contrast to the East African long-term drying trend that was punctuated by periodic extreme wet and dry periods. The comparison of the climate history of these two regions suggests that Southern Africa may have been a safe refuge for hominins and other animals during the last 3.5 Myrs and thus important implications for our understand of early human evolution.

  4. Monitoring and Threat Assessment of the Spotted-Necked Otter (Lutra maculicollis) in Southern Benin Wetlands

    OpenAIRE

    Mensah, G A; Sinsin, B.; H.A. Akpona

    2011-01-01

    Otters are a very poorly studied species in most of Africa and Benin is no exception. This is due to their inaccessible habitat (river valleys), their retiring behaviour, and the difficulty of having no specific survey methods. An interview survey of local people was carried out in 2004 by the Laboratory of Applied Ecology in Southern Benin wetlands (6°28’N to 7°N; 2°23’E to 2°35’E) to assess the threats to spotted-necked otters. The results showed that yearlings dominated the demographic str...

  5. Onchocerciasis in West Africa after 2002: a challenge to take up

    Directory of Open Access Journals (Sweden)

    Hougard J.M.

    2002-06-01

    Full Text Available Initially planned for a 20 year life time, the Onchocerciasis Control Programme in West Africa (OCP will have finally continued its activities for nearly three decades (vector control alone from 1975 to 1989, then vector control and/or therapeutic treatment until 2002. Although onchocerciasis is no longer a problem of public health importance nor an obstacle to socioeconomic development in the OCP area, the control of this filariasis is not over because OCP never aimed at eradication, neither of the parasite (Onchocerca volvulus, nor of its vector (Simulium damnosum s.l.. In 2003, the eleven Participating countries of OCP will take over the responsibility of carrying out the residual activities of monitoring and the control of this disease. This mission is of great importance because any recrudescence of the transmission could lead in the long run to the reappearance of the clinical signs of onchocerciasis, if not its most serious manifestations. For epidemiological and operational reasons, and given the disparity in national health policies and infrastructures, the capacities of the countries to take over the residual activities of monitoring and control of onchocerciasis are very unequal. Indeed, the interventions to be carried out are very different from one country to another and the process of integrating the residual activities into the national health systems is not taking place at the same pace. This inequality among the countries vis-a-vis the challenges to be met does not, however, prejudge the epidemiological situation after 2002 whose evolution will also depend on the effectiveness of the provisions made before that date by OCP, then after 2002, by the Regional Office for Africa of the World Health Organization which is currently setting up a sub-regional multidisease surveillance centre.

  6. Radiative impact of mineral dust on monsoon precipitation variability over West Africa

    Directory of Open Access Journals (Sweden)

    C. Zhao

    2010-11-01

    Full Text Available The radiative forcing of dust and its impact on precipitation over the West Africa monsoon (WAM region is simulated using a coupled meteorology and aerosol/chemistry model (WRF-Chem. During the monsoon season, dust is a dominant contributor to aerosol optical depth (AOD over West Africa. In the control simulation, on 24-h domain average, dust has a cooling effect (−6.11 W/m2 at the surface, a warming effect (6.94 W/m2 in the atmosphere, and a relatively small TOA forcing (0.83 W/m2. Dust modifies the surface energy budget and atmospheric diabatic heating and hence causes lower atmospheric cooling in the daytime but warming in the nighttime. As a result, atmospheric stability is increased in the daytime and reduced in the nighttime, leading to a reduction of late afternoon precipitation by up to 0.14 mm/h (25% and an increase of nocturnal and early morning precipitation by up to 0.04 mm/h (45% over the WAM region. Dust-induced reduction of diurnal precipitation variation improves the simulated diurnal cycle of precipitation when compared to measurements. However, daily precipitation is only changed by a relatively small amount (−0.17 mm/day or −4%. The dust-induced change of WAM precipitation is not sensitive to interannual monsoon variability. On the other hand, sensitivity simulations show that, from weaker to stronger absorbing dust representing the uncertainty in dust solar absorptivity, dust longwave warming effect in the nighttime surpasses its shortwave cooling effect in the daytime at the surface, leading to a less stable atmosphere associated with more convective precipitation in the nighttime. As a result, the dust-induced change of daily WAM precipitation varies from a significant reduction of −0.52 mm/day (−12%, weaker absorbing dust to a small increase of 0.03 mm/day (1%, stronger absorbing dust. This variation originates from the competition between dust impact on daytime and nighttime

  7. Vertical structure of aerosols and water vapor over West Africa during the African monsoon dry season

    Directory of Open Access Journals (Sweden)

    S.-W. Kim

    2009-10-01

    Full Text Available We present observations of tropospheric aerosol and water vapor transport over West Africa and the associated meteorological conditions during the AMMA SOP-0 dry season experiment, which was conducted in West Africa in January–February 2006. This study combines data from ultra-light aircraft (ULA-based lidar, airborne in-situ aerosol and gas measurements, standard meteorological measurements, satellite-based aerosol measurements, airmass trajectories, and radiosonde measurements. At Niamey (13.5° N, 2.2° E the prevailing surface wind (i.e. Harmattan was from the northeast bringing dry dusty air from the Sahara desert. High concentrations of mineral dust aerosol were typically observed from the surface to 1.5 or 2 km associated with the Saharan airmasses. At higher altitudes the prevailing wind veered to the south or southeast bringing relatively warm and humid airmasses from the biomass burning regions to the Sahel (<10° N. These elevated layers had high concentrations of biomass burning aerosol and were typically observed between altitudes of 2–5 km. Meteorological analyses show these airmasses were advected upwards over the biomass burning regions through ascent in Inter-Tropical Discontinuity (ITD zone. Aerosol vertical profiles obtained from the space-based lidar CALIOP onboard CALIPSO during January 2007 also showed the presence of dust particles (particle depolarization (δ~30%, lidar Ångström exponent (LAE<0, aerosol backscatter to extinction ratio (BER: 0.026~0.028 sr−1 at low levels (<1.5 km and biomass burning smoke aerosol (δ<10%, LAE: 0.6~1.1, BER: 0.015~0.018 sr−1 between 2 and 5 km. CALIOP data indicated that these distinct continental dust and biomass burning aerosol layers likely mixed as they advected further south over the tropical Atlantic Ocean, as indicated an intermediate values of δ (10~17%, LAE (0.16~0.18 and BER (0.0021~0.0022 sr−1.

  8. A disseminated case of Buruli ulcer at Macenta in the forest region of Guinea in West Africa

    Institute of Scientific and Technical Information of China (English)

    Bafende Aombe Eric; Strahm Stefan; Loua Richard.; Beavogui Galada Daniel; Kolie Valentin; Guilavogui Raphael; Keita Samba

    2012-01-01

    The author report a confirmed case of Buruli ulcer at Macenta in the forest region of Guinea in West Africa. An 8 years old girl came to the general hospital of Macenta located in the forest region of Guinea at 800km south-west of Conakry. Her story reveals that she used to swim in the local river of Man region in Ivory Coast. There is no notion of trauma or insect bite .The disease started 2 years ago by a nodule of the skin in her right leg which had ulcerated; she received various traditional treatments.

  9. The use of seasonal forecasts in a crop failure early warning system for West Africa

    Science.gov (United States)

    Nicklin, K. J.; Challinor, A.; Tompkins, A.

    2011-12-01

    Seasonal rainfall in semi-arid West Africa is highly variable. Farming systems in the region are heavily dependent on the monsoon rains leading to large variability in crop yields and a population that is vulnerable to drought. The existing crop yield forecasting system uses observed weather to calculate a water satisfaction index, which is then related to expected crop yield (Traore et al, 2006). Seasonal climate forecasts may be able to increase the lead-time of yield forecasts and reduce the humanitarian impact of drought. This study assesses the potential for a crop failure early warning system, which uses dynamic seasonal forecasts and a process-based crop model. Two sets of simulations are presented. In the first, the crop model is driven with observed weather as a control run. Observed rainfall is provided by the GPCP 1DD data set, whilst observed temperature and solar radiation data are given by the ERA-Interim reanalysis. The crop model used is the groundnut version of the General Large Area Model for annual crops (GLAM), which has been designed to operate on the grids used by seasonal weather forecasts (Challinor et al, 2004). GLAM is modified for use in West Africa by allowing multiple planting dates each season, replanting failed crops and producing parameter sets for Spanish- and Virginia- type West African groundnut. Crop yields are simulated for three different assumptions concerning the distribution and relative abundance of Spanish- and Virginia- type groundnut. Model performance varies with location, but overall shows positive skill in reproducing observed crop failure. The results for the three assumptions are similar, suggesting that the performance of the system is limited by something other than information on the type of groundnut grown. In the second set of simulations the crop model is driven with observed weather up to the forecast date, followed by ECMWF system 3 seasonal forecasts until harvest. The variation of skill with forecast date

  10. Effects of climate variability on savannah fire regimes in West Africa

    Science.gov (United States)

    N'Datchoh, E. T.; Konaré, A.; Diedhiou, A.; Diawara, A.; Quansah, E.; Assamoi, P.

    2015-04-01

    The main objective of this work is to investigate at regional scale the variability in burned areas over the savannahs of West Africa and their links with the rainfall and the large-scale climatic indexes such as the Southern Oscillation Index (SOI), Multivariate ENSO Index (MEI), North Atlantic Oscillation (NAO) and sea surface temperature gradient (SSTG). Daily satellite products (L3JRC) of burned areas from the SPOT Vegetation sensor at a moderate spatial resolution of 1 km x 1 km between 2000 and 2007 were analyzed over the West African savannah in this paper. Results from seasonal analysis revealed a large increase in burned areas from November to February, with consistent peaks in December at the regional scale. In addition, about 30% of the pixels are burned at least four times within the 7-year period. Positive correlations were found between burned areas and rainfall values obtained from the TRMM satellite over savannahs located above 8° N, meaning that a wet rainfall season over these regions was favorable to biomass availability in the next dry season and therefore may induce an increase in burned areas in this region. Moreover, our results showed a nonlinear relationship between the large-scale climatic indexes SOI, MEI, NAO and SSTG and burned-area anomalies. Positive (negative) correlations between burned areas and SOI (MEI) were consistent over the Sahel and Sudano-Sahelian areas. Negative correlations with Atlantic SSTG were significant over the Guinea subregion. Correlations between burned areas over Sudano-Guinean subregion and all the large-scale indexes were weak and may be explained by the fact that this subregion had a mean rainfall greater than 800 mm yr-1 with permanent biomass availability and an optimal amount of soil moisture favorable to fire practice irrespective of the climate conditions. The teleconnection with NAO was not clear and needed to be investigated further.

  11. Facilitating institutional change in West Africa: the CoS–SIS experience

    OpenAIRE

    Adjei-Nsiah, S.; O. Sakyi-Dawson; Klerkx, L.W.A.

    2014-01-01

    The Convergence of Sciences–Strengthening Innovation Systems (CoS–SIS) programme is based on the premise that the livelihood of the African smallholder farmer is constrained by the existence and/or performance of formal and informal institutions that are not conducive to small-farm development. CoS–SIS employs nine platforms in Ghana, Benin and Mali – “Concertation and Innovation Groups” (CIGs) – that aim to facilitate institutional change above the farm level (e.g. rules and regulations, byl...

  12. Mycobiota and identification of aflatoxin gene cluster in marketed spices in West Africa

    DEFF Research Database (Denmark)

    Gnonlonfin, G. J. B.; Adjovi, Y. C.; Tokpo, A. F.;

    2013-01-01

    Fungal infection and aflatoxin contamination were evaluated on 114 samples of dried and milled spices such as ginger, garlic and black pepper from southern Benin and Togo collected in November 2008 -January 2009. These products are dried to preserve them for lean periods available throughout...... the year. Fungal contamination was evaluated after plating on selective media with a total of 20 fungal genera identified, ranging from 7 in garlic to 14 in ginger. Ginger and pepper showed high incidence of fungal contamination compared to garlic that had lower levels of fungal contamination. Species...

  13. The Quest for the Africa-Eurasia plate boundary West of the Strait of Gibraltar

    Science.gov (United States)

    Zitellini, N.

    2009-04-01

    A new swath bathymetry compilation of the Gulf of Cadiz Area and SW Iberia is presented. The new map is the result of a collaborative research performed after year 2000 by teams from 7 European countries and 14 research institutions. This new dataset allow for the first time to present and to discuss the missing link in the plate boundary between Eurasia and Africa in the Central Atlantic. A set of almost linear and sub parallel dextral strike-slip faults, the SWIM Faults (SWIM is the acronym of the ESF EuroMargins project "Earthquake and Tsunami hazards of active faults at the South West Iberian Margin: deep structure, high-resolution imaging and paleoseismic signature") was mapped using a the new swath bathymetry compilation available in the area. The SWIM Faults form a narrow band of deformation over a length of 600 km coincident with a small circle centred on the pole of rotation of Africa with respect to Eurasia, This narrow band of deformation connects the Gloria Fault to the Rif-Tell Fault Zone, two segments of the plate boundary between Africa and Eurasia. In addition, the SWIM faults cuts across the Gulf of Cadiz, in the Atlantic Ocean, where the 1755 Great Lisbon earthquake, M~8.5-8.7, and tsunami were generated, providing a new insights on its source location. SWIM Team: E. Gràcia (2), L. Matias (3), P. Terrinha (4), M.A. Abreu (5), G. DeAlteriis(6), J.P. Henriet (7), J.J. Dañobeitia (2), D.G. Masson (8), T. Mulder (9), R. Ramella (10), L. Somoza (11) and S. Diez (2) (2) Unitat de Tecnologia Marina (CSIC), Centre Mediterrani d'Investigacions Marines i Ambientals, Barcelona, Spain (3) Centro Geofísica da Universidade de Lisboa (CGUL, IDL), Lisboa, Portugal (4) National Institute for Engineering, Technology and Innovation (INETI, LATTEX), Departamento de Geologia Marinha, Amadora, Portugal (5) Estrutura de Missão para a Extensão da Plataforma Continental, Lisboa, Portugal (6) Geomare Sud IAMC, CNR, Napoli, Italy (7) Renard Centre of Marine Geology

  14. Improving the management of reproduction of indigenous cattle in the semiarid and subhumid zones of West Africa

    International Nuclear Information System (INIS)

    The traditional systems of management of reproduction of cattle indigenous to West Africa and various improvement strategies employed are reviewed. Strategies have been evolved to facilitate early attainment of puberty and first conception, reduce inter-calving intervals and control oestrous and the oestrous cycle. Among the strategies and techniques used to achieve various degrees of improvement in these reproductive parameters are improved nutrition, diagnosis and control of diseases, determination of hormonal profiles and semen characteristics, and administration of drugs as well as strategic management practices. More investigations are required for a full understanding of the factors influencing reproductive performance and identification of the most appropriate management practices necessary to improve the reproductive efficiency of cattle indigenous to West Africa. (author). 97 refs, 4 figs, 10 tabs

  15. THE IMPACT OF HOUSEHOLD-LEVEL DETERMINANTS OF CHILD HEALTH AND NUTRITION: CROSS-COUNTRY EVIDENCE FROM WEST AFRICA

    OpenAIRE

    Penders, Christopher L.; Staatz, John M.

    2001-01-01

    Poor child health and nutrition persist throughout West Africa. This research analyzes the impact of key economic variables, including income, education and background characteristics, on child health and nutrition across nine different countries. The results are interpreted in the context of differing levels of economic development among these nations. The findings do not show wealth and parental education to be robust across the sample, but maternal background characteristics have a positiv...

  16. Physiology and development of the M and S molecular forms of Anopheles gambiae in Burkina Faso (West Africa)

    OpenAIRE

    Mouline, Karine; Mamai, W.; Agnew, P.; Tchonfienet, M.; Brengues, Cécile; Dabiré, R.; Robert, Vincent; Simard, Frédéric

    2012-01-01

    In West Africa, M and S molecular forms of Anopheles gambiae sensu stricto (Diptera: Culicidae) Giles, frequently occur together, although with different population bionomics. The S form typically breeds in rain-dependant water collections and is present during the rainy season only whereas the M form can thrive all year long in areas with permanent breeding opportunities. In the present study, we explored physiological and developmental trade-offs at play in laboratory colonies and field pop...

  17. Utilisation of traditional and indigenous foods in the North West Province of South Africa / Sarah Tshepho Pona Matenge

    OpenAIRE

    Matenge, Sarah Tshepho Pona

    2011-01-01

    AIM AND OBJECTIVES The main aim of this thesis was to explore the possibilities of promoting the cultivation, utilisation and consumption of indigenous and traditional plant foods (ITPF) among urban and rural communities in the North West Province of South Africa that could possibly lead to increased IK and dietary diversity. The objectives were the following: Assess consumption of TLV in the rural and urban communities. Compare nutritional status of consumers and non-consumers of ...

  18. First GIS Analysis of Modern Stone Tools Used by Wild Chimpanzees (Pan troglodytes verus) in Bossou, Guinea, West Africa

    OpenAIRE

    Alfonso Benito-Calvo; Susana Carvalho; Adrian Arroyo; Tetsuro Matsuzawa; Ignacio de la Torre

    2015-01-01

    Stone tool use by wild chimpanzees of West Africa offers a unique opportunity to explore the evolutionary roots of technology during human evolution. However, detailed analyses of chimpanzee stone artifacts are still lacking, thus precluding a comparison with the earliest archaeological record. This paper presents the first systematic study of stone tools used by wild chimpanzees to crack open nuts in Bossou (Guinea-Conakry), and applies pioneering analytical techniques to such artifacts. Aut...

  19. Raising livestock in resource-poor communities of the North West Province of South Africa - a participatory rural appraisal study

    OpenAIRE

    J.K. Getchell; A.F. Vatta; P.W. Motswatswe; R.C. Krecek; R. Moerane; A. N. Pell; Tucker, T. W.; S. Leshomo

    2002-01-01

    A participatory research model was used in six village communities in the Central Region of the North West Province of South Africa in order to achieve the following broad objectives : to obtain information on the challenges owners face in raising livestock in these areas and to evaluate the livestock owners' level of knowledge of internal parasites in their animals. Information obtained at participatory workshops clearly indicated a need for improvements in water supply, schools, job creatio...

  20. Improving SME access to finance in the North-West Province of South Africa / Imraan G.H. Bakhas.

    OpenAIRE

    Bakhas, Imraan Goolam Hoosen

    2009-01-01

    The purpose of this study is to provide empirical, qualitative evidence concerning the factors within the supply, demand and institutional support environments that hinder SME access to finance as well as the interventions necessary to improve access to finance for SMEs in the North West Province (NWP) of South Africa. The semi-structured interview technique was used to collect data from a sample of 25 organisations. A response rate of 56% comprising two financial institutions and 12 SME sup...

  1. Agricultural innovation platforms in West Africa: How does strategic institutional entrepreneurship unfold in different value chain contexts?

    OpenAIRE

    Paassen, van, R.A.; Klerkx, L.W.A.; Adjei-Nsiah, S.; Adu-Acheampong, R.; Ouologuem, B.; Zannou, E.

    2014-01-01

    Inspired by Innovation System theory, donors promote Innovation Platforms (IP) to enhance collaboration for development. However, the question arises whether this is the best approach to facilitate change. The article presents the experience of an action-research programme (2009-2013) on the value of IPs for creating institutional change for the benefit of smallholders, in various value chain contexts in West Africa. We analyse the cases from a dialectic perspective on institutional entrepren...

  2. Urban nature conservation: vegetation of natural areas in the Potchefstroom municipal area, North West Province, South Africa

    OpenAIRE

    Cilliers, S.S.; Van Wyk, E; G.J. Bredenkamp

    1999-01-01

    This study on the natural and degraded natural vegetation of natural areas in the Potchefstroom Municipal Area, forms part of a research programme on spontaneous vegetation in urban open spaces in the North West Province, South Africa. Using a numerical classification technique (TWINSPAN) as a first approximation, the classification was refined by applying Braun-Blanquet procedures. The result is a phytosociological table from which 6 plant communities were recognised, which are subdivided in...

  3. Problems and prospects in the utilisation of animal traction in semi-arid West Africa: Evidence from Niger

    OpenAIRE

    Williams, T. O.

    1998-01-01

    Sustained adoption of animal traction for crop cultivation in the semi-arid zone of West Africa has been slow despite deliberate attempts by governments, development agencies and research organizations. to promote its use among small-scale farmers. The low adoption rates are partly due to demand and supply constraints, combined with the absence of certain preconditions (e.g appropriate climatic and biophysical attributes, and farming practices). On the demand side, factors like the short term...

  4. Natural infection of cowpea (Vigna unguiculata (L.) Walp.) by toxigenic fungi and mycotoxin contamination in Benin, West Africa

    DEFF Research Database (Denmark)

    Houssou, P.A.; Ahohuendo, B.C.; Fandohan, P.;

    2009-01-01

    for the two periods. About 23 fungal species were identified on cowpea seed samples across zones of which Aspergillus flavus, a fungus that produces aflatoxins, was most frequently encountered. Fusarium species shown to produce fumonisins were not recorded from cowpea seeds. Overall incidence of A. flavus...... infection was found to increase after storage from 7.6% at T0 to 28.25% at T3. In spite of this natural infection of cowpea, very low levels of fumonisin and aflatoxin were detected. Only three out of the 92 cowpea samples, all collected at T0, were found to be fumonisin B1 positive with a mean level of 0.......03 mg/g. Similarly, only six samples out of the 92, all collected at T3, were aflatoxin B1 positive with mean levels of 3.58 µg/kg. Fumonisin (B2 and B3) and aflatoxin (B2, G1 and G2) were not detected in any of the samples. Contrary to the situation with maize and groundnut where high levels of toxin...

  5. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

    NARCIS (Netherlands)

    A.F.V. Howard; R. N'Guessan; C.J.M. Koenraadt; A. Asidi; M. Farenhorst; M. Akogbeto; M.B. Thomas; B.G.J. Knols; W. Takken

    2010-01-01

    Background: Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show tha

  6. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

    NARCIS (Netherlands)

    Howard, A.F.V.; N'Guessan, R.; Koenraadt, C.J.M.; Asidi, A.; Farenhorst, M.; Akogbéto, M.; Thomas, M.B.; Knols, B.G.J.; Takken, W.

    2010-01-01

    Background Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show that

  7. Lions of West Africa : ecology of lion (Panthera leo Linnaeus 1975) populations and human-lion conflicts in Pendjari Biosphere Reserve, North Benin

    NARCIS (Netherlands)

    Sogbohossou, Etotépé Aïkpémi

    2011-01-01

    The Earth’s biodiversity is disappearing at an alarming rate in the last decades. Many species, including carnivores, are becoming endangered. The lion was one of the most widely distributed terrestrial mammals and is today restricted to Gir ecosystem in India and to more or less fragmented populati

  8. Impact of acadja fisheries on the population dynamics of Sarotherodon melanotheron and Hemichromis fasciatus in a Lake Nokoué (Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Niyonkuru C.

    2010-08-01

    Full Text Available In Lake Nokoué fishermen have developed the acadjas system which operates as an extensive aquaculture practice. Little is known about the population dynamics of fish fauna which colonizes those acadjas. Therefore, population parameters of two cichlids of Lake Nokoué, Sarotherodon melanotheron and Hemichromis fasciatus, sampled in areas within and without acadjas were investigated using length-frequency data collected between June 2003 and December 2004. For the two species, asymptotic length, L∞ was higher within than without acadjas (26.8 cm and 24.1 cm respectively for S. melanotheron; 18.5 cm and 16.5 cm respectively for H. faciatus. K and Φ′ values recorded outside acadjas were higher than inside acadjas for H. fasciatus whereas the same values were very slightly different without and within acadjas for S. melanotheron. H. fasciatus is a fish predator and branches or woody debris of acadjas are not favourable for its hunting activities.The total and natural mortality rates for the two species were higher outside than inside acadjas showing so the role of protection insured by acadjas systems. Acadjas have more impact on H. fasciatus than on S. melanotheron. A possibility of management is to reorganize the distribution of acadjas over Lake Nokoué in order to keep some areas in which no acadjas would be allowed for fish species that growth is better without acadjas.

  9. Governance of Protected Areas in West Africa - The case of the W-Arly-Pendjari (WAP) Complex in Benin and Burkina Faso

    OpenAIRE

    Konrad, Tillmann

    2015-01-01

    Protected areas are the central strategy for preserving biodiversity in the face of overexploitation and global change. To ensure their long-term survival, however, these areas may not be regarded as last havens of wilderness, but as complex social-ecological systems. Modern approaches of protected area (PA) management support this view by balancing conservation and development issues in a sustainable way and adapted to the local context. However, success of these strategies in achieving thei...

  10. Deciphering Dynamics of Recent Epidemic Spread and Outbreak in West Africa: The Case of Ebola Virus

    Science.gov (United States)

    Upadhyay, Ranjit Kumar; Roy, Parimita

    Recently, the 2014 Ebola virus (EBOV) outbreak in West Africa was the largest outbreak to date. In this paper, an attempt has been made for modeling the virus dynamics using an SEIR model to better understand and characterize the transmission trajectories of the Ebola outbreak. We compare the simulated results with the most recent reported data of Ebola infected cases in the three most affected countries Guinea, Liberia and Sierra Leone. The epidemic model exhibits two equilibria, namely, the disease-free and unique endemic equilibria. Existence and local stability of these equilibria are explored. Using central manifold theory, it is established that the transcritical bifurcation occurs when basic reproduction number passes through unity. The proposed Ebola epidemic model provides an estimate to the potential number of future cases. The model indicates that the disease will decline after peaking if multisectorial and multinational efforts to control the spread of infection are maintained. Possible implication of the results for disease eradication and its control are discussed which suggests that proper control strategies like: (i) transmission precautions, (ii) isolation and care of infectious Ebola patients, (iii) safe burial, (iv) contact tracing with follow-up and quarantine, and (v) early diagnosis are needed to stop the recurrent outbreak.

  11. IASI-derived Surface Temperature Under Dusty Conditions: Application to the West Africa Region.

    Science.gov (United States)

    Mechri, Rihab; Capelle, Virginie; Chedin, Alain

    2016-04-01

    Giving access to energy and water budgets, Surface Temperature (ST) is considered as a key variable for a wide range of applications in particular for meteorology and climatology. An accurate knowledge of this variable should significantly improve the monitoring of numerous atmospheric and surface processes as well as their interactions. Even-though satellite sensors bring ST global fields at different spatial and temporal scales, the accuracy of these products is still questionable especially over land or for complex atmospheric conditions (presence of clouds, of aerosols, etc.). At LMD, the ST is determined through the simultaneous "Look-up-Table" inversion of satellite METOP/IASI radiances in terms of Aerosol Optical Depth (AOD), dust layer mean altitude and surface temperature . The main aim of this work is to validate IASI ST product and to analyze its spatial and temporal variability, in particular in the presence of dust aerosols. This approach has been first applied to the West Africa region. The accuracy of this ST product will be assessed in terms of bias and standard deviation against ST products from ECMWF forecast, from other satellite products (MODIS AQUA/TERRA, AATSR,…) and from in-situ measurements for different periods ranging from July 2007 to today according to the availability of these validation data.

  12. Oxygen, hydrogen, and helium isotopes for investigating groundwater systems of the Cape Verde Islands, West Africa

    Science.gov (United States)

    Heilweil, V.M.; Solomon, K.D.; Gingerich, S.B.; Verstraeten, Ingrid M.

    2009-01-01

    Stable isotopes (??18O, ??2H), tritium (3H), and helium isotopes (3He, 4He) were used for evaluating groundwater recharge sources, flow paths, and residence times of three watersheds in the Cape Verde Islands (West Africa). Stable isotopes indicate the predominance of high-elevation precipitation that undergoes little evaporation prior to groundwater recharge. In contrast to other active oceanic hotspots, environmental tracers show that deep geothermal circulation does not strongly affect groundwater. Low tritium concentrations at seven groundwater sites indicate groundwater residence times of more than 50 years. Higher tritium values at other sites suggest some recent recharge. High 4He and 3He/4He ratios precluded 3H/3He dating at six sites. These high 3He/4He ratios (R/Ra values of up to 8.3) are consistent with reported mantle derived helium of oceanic island basalts in Cape Verde and provided end-member constraints for improved dating at seven other locations. Tritium and 3H/3He dating shows that S??o Nicolau Island's Ribeira Faj?? Basin has groundwater residence times of more than 50 years, whereas Fogo Island's Mosteiros Basin and Santo Ant??o Island's Ribeira Paul Basin contain a mixture of young and old groundwater. Young ages at selected sites within these two basins indicate local recharge and potential groundwater susceptibility to surface contamination and/or salt-water intrusion. ?? Springer-Verlag 2009.

  13. Intercomparison of Evapotranspiration Over the Savannah Volta Basin in West Africa Using Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    T. P. Burt

    2008-04-01

    Full Text Available This paper compares evapotranspiration estimates from two complementary satellite sensors – NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS and ESA’s ENVISAT Advanced Along-Track Scanning Radiometer (AATSR over the savannah area of the Volta basin in West Africa. This was achieved through solving for evapotranspiration on the basis of the regional energy balance equation, which was computationally-driven by the Surface Energy Balance Algorithm for Land algorithm (SEBAL. The results showed that both sensors are potentially good sources of evapotranspiration estimates over large heterogeneous landscapes. The MODIS sensor measured daily evapotranspiration reasonably well with a strong spatial correlation (R2=0.71 with Landsat ETM+ but underperformed with deviations up to ~2.0 mm day-1, when compared with local eddy correlation observations and the Penman-Monteith method mainly because of scale mismatch. The AATSR sensor produced much poorer correlations (R2=0.13 with Landsat ETM+ and conventional ET methods also because of differences in atmospheric correction and sensor calibration over land.

  14. The Global Politics of Gay Rights: The Straining Relations between the West and Africa

    Directory of Open Access Journals (Sweden)

    Hakeem Onapajo

    2016-01-01

    Full Text Available This article analyses the contemporary global politics of gay rights as it relates to the straining relations between the Western powers and many African states that oppose sexual minorities’ rights. While the West (with emphasis on the United States, EU, and Britain advocates for the protection of gay rights in the world, Africa provides the largest concentration of states opposed to them. Therefore, there has been rising tension between both regions. This became more apparent after Nigeria and Uganda, respectively, signed their anti-gay bills into law in January and February 2014. In response to this, the Western powers decided to take some punitive measures, especially imposition of sanctions, against the countries to pressurise them to repeal their laws. In an unusual manner, the African states are radically determined to go ahead with their anti-gay laws in open defiance to the demands of the Western powers. This development, which is informed by a number of factors, shows a rather new pattern of behaviour by African states in global politics.

  15. Farmer-Managed Natural Regeneration Enhances Rural Livelihoods in Dryland West Africa

    Science.gov (United States)

    Weston, Peter; Hong, Reaksmey; Kaboré, Carolyn; Kull, Christian A.

    2015-06-01

    Declining agricultural productivity, land clearance and climate change are compounding the vulnerability of already marginal rural populations in West Africa. `Farmer-Managed Natural Regeneration' (FMNR) is an approach to arable land restoration and reforestation that seeks to reconcile sustained food production, conservation of soils, and protection of biodiversity. It involves selecting and protecting the most vigorous stems regrowing from live stumps of felled trees, pruning off all other stems, and pollarding the chosen stems to grow into straight trunks. Despite widespread enthusiasm and application of FMNR by environmental management and development projects, to date, no research has provided a measure of the aggregate livelihood impact of community adoption of FMNR. This paper places FMNR in the context of other agroforestry initiatives, then seeks to quantify the value of livelihood outcomes of FMNR. We review published and unpublished evidence about the impacts of FMNR, and present a new case study that addresses gaps in the evidence-base. The case study focuses on a FMNR project in the district of Talensi in the semi-arid Upper East Region in Ghana. The case study employs a social return on investment analysis, which identifies proxy financial values for non-economic as well as economic benefits. The results demonstrate income and agricultural benefits, but also show that asset creation, increased consumption of wild resources, health improvements, and psycho-social benefits created more value in FMNR-adopting households during the period of the study than increases in income and agricultural yields.

  16. Population genetic structure of Plasmodium falciparum across a region of diverse endemicity in West Africa

    Directory of Open Access Journals (Sweden)

    Mobegi Victor A

    2012-07-01

    Full Text Available Abstract Background Malaria parasite population genetic structure varies among areas of differing endemicity, but this has not been systematically studied across Plasmodium falciparum populations in Africa where most infections occur. Methods Ten polymorphic P. falciparum microsatellite loci were genotyped in 268 infections from eight locations in four West African countries (Republic of Guinea, Guinea Bissau, The Gambia and Senegal, spanning a highly endemic forested region in the south to a low endemic Sahelian region in the north. Analysis was performed on proportions of mixed genotype infections, genotypic diversity among isolates, multilocus standardized index of association, and inter-population differentiation. Results Each location had similar levels of pairwise genotypic diversity among isolates, although there were many more mixed parasite genotype infections in the south. Apart from a few isolates that were virtually identical, the multilocus index of association was not significant in any population. Genetic differentiation between populations was low (most pairwise FST values  Conclusions Although proportions of mixed genotype infections varied with endemicity as expected, population genetic structure was similar across the diverse sites. Very substantial reduction in transmission would be needed to cause fragmented or epidemic sub-structure in this region.

  17. Mercury, hydroquinone and clobetasol propionate in skin lightening products in West Africa and Canada.

    Science.gov (United States)

    Gbetoh, Mètogbé Honoré; Amyot, Marc

    2016-10-01

    Skin lightening products are types of cosmetics (creams, gels, lotions and soaps) applied voluntarily on skin. Several of these products contain a variety of active ingredients that are highly toxic. Among those toxic agents, the present study focuses on mercury, hydroquinone, and clobetasol propionate. Out of the 93 lightening soaps and 98 creams purchased in large city markets in sub-Saharan West Africa and in small ethnic shops in Canada, 68-84% of all creams and 7.5-65% of all soaps exceeded regulatory guidelines for at least one active ingredient when considering different regulations. Mercury was found in high concentrations mainly in soaps, while hydroquinone and clobetasol propionate concentrations exceeded US FDA standards in some creams for all countries included in our study. Concentrations of the three compounds declared on labels of soaps and creams usually did not correspond to concentrations actually measured, particularly for mercury and hydroquinone. Overall, our results indicate that most studied skin-lightening products are potentially toxic and that product labels are frequently inaccurate with respect to the presence of toxic agents. PMID:27372064

  18. HIV-2 integrase variation in integrase inhibitor-naive adults in Senegal, West Africa.

    Directory of Open Access Journals (Sweden)

    Geoffrey S Gottlieb

    Full Text Available BACKGROUND: Antiretroviral therapy for HIV-2 infection is hampered by intrinsic resistance to many of the drugs used to treat HIV-1. Limited studies suggest that the integrase inhibitors (INIs raltegravir and elvitegravir have potent activity against HIV-2 in culture and in infected patients. There is a paucity of data on genotypic variation in HIV-2 integrase that might confer intrinsic or transmitted INI resistance. METHODS: We PCR amplified and analyzed 122 HIV-2 integrase consensus sequences from 39 HIV-2-infected, INI-naive adults in Senegal, West Africa. We assessed genetic variation and canonical mutations known to confer INI-resistance in HIV-1. RESULTS: No amino acid-altering mutations were detected at sites known to be pivotal for INI resistance in HIV-1 (integrase positions 143, 148 and 155. Polymorphisms at several other HIV-1 INI resistance-associated sites were detected at positions 72, 95, 125, 154, 165, 201, 203, and 263 of the HIV-2 integrase protein. CONCLUSION: Emerging genotypic and phenotypic data suggest that HIV-2 is susceptible to the new class of HIV integrase inhibitors. We hypothesize that intrinsic HIV-2 integrase variation at "secondary" HIV-1 INI-resistance sites may affect the genetic barrier to HIV-2 INI resistance. Further studies will be needed to assess INI efficacy as part of combination antiretroviral therapy in HIV-2-infected patients.

  19. Modelling social vulnerability in sub-Saharan West Africa using a geographical information system

    Directory of Open Access Journals (Sweden)

    Olanrewaju Lawal

    2015-02-01

    Full Text Available In recent times, disasters and risk management have gained significant attention, especially with increasing awareness of the risks and increasing impact of natural and other hazards especially in the developing world. Vulnerability, the potential for loss of life or property from disaster, has biophysical or social dimensions. Social vulnerability relates to societal attributes which has negative impacts on disaster outcomes. This study sought to develop a spatially explicit index of social vulnerability, thus addressing the dearth of research in this area in sub-Saharan Africa. Nineteen variables were identified covering various aspects. Descriptive analysis of these variables revealed high heterogeneity across the South West region of Nigeria for both the state and the local government areas (LGAs. Feature identification using correlation analysis identified six important variables. Factor analysis identified two dimensions, namely accessibility and socioeconomic conditions, from this subset. A social vulnerability index (SoVI showed that Ondo and Ekiti have more vulnerable LGAs than other states in the region. About 50% of the LGAs in Osun and Ogun have a relatively low social vulnerability. Distribution of the SoVI shows that there are great differences within states as well as across regions. Scores of population density, disability and poverty have a high margin of error in relation to mean state scores. The study showed that with a geographical information system there are opportunities to model social vulnerability and monitor its evolution and dynamics across the continent.

  20. Poverty, health and satellite-derived vegetation indices: their inter-spatial relationship in West Africa

    Science.gov (United States)

    Sedda, Luigi; Tatem, Andrew J.; Morley, David W.; Atkinson, Peter M.; Wardrop, Nicola A.; Pezzulo, Carla; Sorichetta, Alessandro; Kuleszo, Joanna; Rogers, David J.

    2015-01-01

    Background Previous analyses have shown the individual correlations between poverty, health and satellite-derived vegetation indices such as the normalized difference vegetation index (NDVI). However, generally these analyses did not explore the statistical interconnections between poverty, health outcomes and NDVI. Methods In this research aspatial methods (principal component analysis) and spatial models (variography, factorial kriging and cokriging) were applied to investigate the correlations and spatial relationships between intensity of poverty, health (expressed as child mortality and undernutrition), and NDVI for a large area of West Africa. Results This research showed that the intensity of poverty (and hence child mortality and nutrition) varies inversely with NDVI. From the spatial point-of-view, similarities in the spatial variation of intensity of poverty and NDVI were found. Conclusions These results highlight the utility of satellite-based metrics for poverty models including health and ecological components and, in general for large scale analysis, estimation and optimisation of multidimensional poverty metrics. However, it also stresses the need for further studies on the causes of the association between NDVI, health and poverty. Once these relationships are confirmed and better understood, the presence of this ecological component in poverty metrics has the potential to facilitate the analysis of the impacts of climate change on the rural populations afflicted by poverty and child mortality. PMID:25733559

  1. Estimating Trends in the Total Fertility Rate with Uncertainty Using Imperfect Data: Examples from West Africa

    Directory of Open Access Journals (Sweden)

    Leontine Alkema

    2012-04-01

    Full Text Available BACKGROUND Estimating the total fertility rate is challenging for many developing countries because of limited data and varying data quality. A standardized, reproducible approach to produce estimates that include an uncertainty assessment is desired. METHODS We develop a method to estimate and assess uncertainty in the total fertility rate over time, based on multiple imperfect observations from different data sources including surveys and censuses. We take account of measurement error in observations by decomposing it into bias and variance and assess both by linear regression on a variety of data quality covariates. We estimate the total fertility rate using a local smoother, and assess uncertainty using the weighted likelihood bootstrap. RESULTS We apply our method to data from seven countries in West Africa and construct estimates and uncertainty intervals for the total fertility rate. Based on cross-validation exercises, we find that accounting for differences in data quality between observations gives better calibrated confidence intervals and reduces bias. CONCLUSIONS When working with multiple imperfect observations from different data sources to estimate the total fertility rate, or demographic indicators in general, potential biases and differences in error variance have to be taken into account to improve the estimates and their uncertainty assessment.

  2. Microcredit in West Africa: how small loans make a big impact on poverty.

    Science.gov (United States)

    Gbezo, B E

    1999-01-01

    This article examines the impact of microfinancing schemes in West Africa and the role of the International Labor Organization (ILO) in their development. Microfinancing or microcredit schemes are meant to create the kind of jobs that can keep households severely hit by the economic crisis afloat. They affect not only the financial, but also the agricultural, crafts, financing of social economy, and social protection sectors of the society. Thus, they contribute to improved access to basic social, health and family planning services and to drinking water. The challenge then, is for institutes to adopt microfinancing and to reach out to more than 100 million families in the region. To realize this, nongovernmental organizations are setting up as veritable microfinancing institutions, which are able to realize the resulting benefits so as to be economically viable. In the context of its role in the development of microfinancing schemes, ILO manages a portfolio of technical cooperation and research projects aimed at identifying and removing constraints in the access to credit, savings, insurance, and other financial services through its Social Finance Unit. In addition, ILO is promoting women's entrepreneurship through the International Small Enterprise Programme and the International Programme on More and Better Jobs for Women. PMID:12295602

  3. Marine incursion: the freshwater herring of Lake Tanganyika are the product of a marine invasion into west Africa.

    Directory of Open Access Journals (Sweden)

    Anthony B Wilson

    Full Text Available The spectacular marine-like diversity of the endemic fauna of Lake Tanganyika, the oldest of the African Great Lakes, led early researchers to suggest that the lake must have once been connected to the ocean. Recent geophysical reconstructions clearly indicate that Lake Tanganyika formed by rifting in the African subcontinent and was never directly linked to the sea. Although the Lake has a high proportion of specialized endemics, the absence of close relatives outside Tanganyika has complicated phylogeographic reconstructions of the timing of lake colonization and intralacustrine diversification. The freshwater herring of Lake Tanganyika are members of a large group of pellonuline herring found in western and southern Africa, offering one of the best opportunities to trace the evolutionary history of members of Tanganyika's biota. Molecular phylogenetic reconstructions indicate that herring colonized West Africa 25-50MYA, at the end of a major marine incursion in the region. Pellonuline herring subsequently experienced an evolutionary radiation in West Africa, spreading across the continent and reaching East Africa's Lake Tanganyika during its early formation. While Lake Tanganyika has never been directly connected with the sea, the endemic freshwater herring of the lake are the descendents of an ancient marine incursion, a scenario which may also explain the origin of other Tanganyikan endemics.

  4. 西非海岸盆地深水区油气地质特征和勘探前景%Deep water petroleum geology and exploration potential of West Africa coastal basins

    Institute of Scientific and Technical Information of China (English)

    徐志诚; 吕福亮; 范国章; 毛超林; 张勇刚; 吴敬武

    2012-01-01

    On the basis of plate tectonic theory and petroleum geology theory,we analyzed the formation and evolution of West Africa coastal basins, studied deepwater exploration data and typical deepwater oil & gas fields, and discussed petroleum geologic characteristics and exploration potential of deepwater areas in West Africa. The evolution of West Africa coastal basins can be divided into pre-rift stage, syn-rift stage, and post-rift stage. Controlled by formation and evolution of the hasins, most of deepwater fields developed in post-rift stage and oil fields are predominant. Oil and gas found in West Africa deepwater settings are generated from Lower Cretaceous (syn-rift stage) lacustrine source rocks, Upper Cretaceous and Tertiary (post-rift stage) marine source rocks. The most important deepwater reservoirs are turbidite channel sandstone. The main types of deepwater traps are combined stratigraphic-structural traps, followed by structural traps and stratigraphic traps. Deepwater exploration potential is best in Lower Congo basin and Niger Delta, and is good in Cote D'ivoire basin, Benin basin and Senegal basin. Douala basin and Rio Muni basin have fair deepwater exploration potential, whereas, deepwater exploration may be highly risky in Kwanza basin.%以板块构造理论和石油地质学理论为基础,通过分析西非海岸盆地的形成和演化,结合西非深水区油气勘探现状和深水油气藏研究结果,总结了西非深水区油气地质特征,并探讨了深水区油气勘探前景.西非海岸盆地的形成演化可以分为前裂谷、裂谷和后裂谷3个阶段.受盆地形成演化的控制,西非海岸盆地烃源岩主要包括裂谷阶段下白垩统湖相烃源岩、后裂谷阶段上白垩统海相烃源岩和古近系一新近系海相烃源岩3套;深水区储层以后裂谷阶段上白垩统和古近系一新近系深水浊积砂岩为主;主要圈闭类型为构造-地层或构造-岩性圈闭,其次为构造圈闭和地

  5. Simulation of efficiency impact of drainage water reuse: case of small-scale vegetable growers in North West Province, South Africa

    NARCIS (Netherlands)

    Speelman, S.; Haese, D' M.F.C.; Haese, D' L.

    2011-01-01

    This paper focuses on estimating the effect of drainage water reuse on the technical efficiency of small-scale vegetable growers in South Africa applying a data envelopment analysis (DEA). In the semi-arid North West Province of South Africa water scarcity and the soon to be implemented water charge

  6. University-level nutrition training in West Africa: cost and financing issues

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2015-11-01

    Full Text Available Background: There is a serious shortage of skilled nutrition professionals in West Africa. Investing in nutrition training is one of the strategies for strengthening the human resource base in nutrition. However, little is known about how nutrition training in the region is financed and the levels of tuition fees charged. The purpose of this study was to provide a comprehensive assessment about the levels of tuition fees charged for nutrition training in the West Africa region and to determine to what extent this is of reach to the average student. Methodology: The data for this study were obtained from 74 nutrition degree programs operating in nine West African countries in 2013 through semi-structured interviews during on-site visits or through self-administered questionnaires. They included the age of the programs, school ownership, tuition fees, financial assistance, and main sources of funding. Tuition fees (in 2013 US$ were expressed per program to enable uniformity and comparability. Simple descriptive and bivariate analyses were performed. Results: Results from 74 nutrition training programs in nine countries showed a wide variation in tuition fees within and between countries. The tuition fees for bachelor's, master's, and doctoral programs, respectively, ranged from 372 to 4,325 (mean: 2,353; 162 to 7,678 (mean: 2,232; and 369 to 5,600 (mean: 2,208. The tuition fees were significantly higher (p<0.05 in private institutions than in public institutions (mean: US$3,079 vs. US$2,029 for bachelor's programs; US$5,118 vs. US$1,820 for master's programs; and US$3,076 vs. US$1,815 for doctoral programs. The difference in the tuition fees between Francophone and Anglophone countries was not statistically significant (mean: US$2,570 vs. US$2,216 for bachelor's programs; US$2,417 vs. US$2,147 for master's programs; US$3,285 vs. US$2,055 for doctoral programs. In most countries, the tuition fees appeared to be out of reach of the average student

  7. Indigenous knowledge on landraces and fonio-based food in Benin.

    Science.gov (United States)

    Ballogou, Vénérande Y; Soumanou, Mohamed M; Toukourou, Fatiou; Hounhouigan, Joseph D

    2014-01-01

    Fonio is a traditional cereal cultivated in many West African countries, where farmers are often the guardians of a rich diversity of landraces or traditional varieties. An investigation conducted in northwest of Benin on indigenous knowledge about fonio landraces and fonio-based traditional foods allowed us to inventory 35 landraces identified by the farmers. Ipormoa, Namba, Icantoni or Kopognakè or Icantoga and Iporhouwan landraces were good to cook paste and couscous and easy to dehusk. Besides, Ipormoa and Iporhouwan landraces had interesting agronomic characteristics. Paste, porridge, and couscous were the main fonio-based foods consumed by farmers in northwest of Benin. PMID:24884554

  8. Field efficacy of a new mosaic long-lasting mosquito net (PermaNet (R) 3.0) against pyrethroid-resistant malaria vectors : a multi centre study in Western and Central Africa

    OpenAIRE

    Corbel, Vincent; Chabi, Joseph; Dabiré, R. K.; Etang, J.; Nwane, P.; Pigeon, O.; Akogbeto, M.; Hougard, Jean-Marc

    2010-01-01

    Background: Due to the spread of pyrethroid-resistance in malaria vectors in Africa, new strategies and tools are urgently needed to better control malaria transmission. The aim of this study was to evaluate the performances of a new mosaic long-lasting insecticidal net (LLIN), i.e. PermaNet (R) 3.0, against wild pyrethroid-resistant Anopheles gambiae s.l. in West and Central Africa. Methods: A multi centre experimental hut trial was conducted in Malanville (Benin), Vallee du Kou (Burkina Fas...

  9. Field efficacy of a new mosaic long-lasting mosquito net (PermaNet® 3.0) against pyrethroid-resistant malaria vectors: a multi centre study in Western and Central Africa

    OpenAIRE

    Pigeon Olivier; Nwane Philippe; Etang Josiane; Dabiré Roch K; Chabi Joseph; Corbel Vincent; Akogbeto Martin; Hougard Jean-Marc

    2010-01-01

    Abstract Background Due to the spread of pyrethroid-resistance in malaria vectors in Africa, new strategies and tools are urgently needed to better control malaria transmission. The aim of this study was to evaluate the performances of a new mosaic long-lasting insecticidal net (LLIN), i.e. PermaNet® 3.0, against wild pyrethroid-resistant Anopheles gambiae s.l. in West and Central Africa. Methods A multi centre experimental hut trial was conducted in Malanville (Benin), Vallée du Kou (Burkina...

  10. Understanding the encounter between Africa and the West in a profound way

    OpenAIRE

    L. Nyirongo

    2003-01-01

    VAN DER WALT, B.J. 2003. Understanding and rebuilding Africa; from desperation today towards expectation for tomorrow. Potchefstroom : Institute of Contemporary Christianity in Africa. 553 p. Price: R150. ISBN: 1-86822-419-8.

  11. Characteristics of HIV-2 and HIV-1/HIV-2 Dually Seropositive Adults in West Africa Presenting for Care and Antiretroviral Therapy

    DEFF Research Database (Denmark)

    Ekouevi, Didier K; Coffie, Patrick A; Messou, Eugene;

    2013-01-01

    HIV-2 is endemic in West Africa. There is a lack of evidence-based guidelines on the diagnosis, management and antiretroviral therapy (ART) for HIV-2 or HIV-1/HIV-2 dual infections. Because of these issues, we designed a West African collaborative cohort for HIV-2 infection within the framework o...

  12. Regional climate change and the impact on hydrology in the Volta Basin of West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Jung, G.

    2006-10-15

    The Volta Basin is a climate sensitive, semi-arid to sub-humid region in West Africa. Livelihood of the population is mainly dependent on agriculture and therefore highly vulnerable to rainfall variability and climate change. For an investigation of the impact of a possible global climate change to regional climate and surface, as well as sub-surface hydrology in the region of the Volta Basin, coupled regional climate-hydrology simulations were performed. Therefore, the mesoscale meteorological model MM5 was set up, fully coupled to a 1-dimensional SVAT (Soil Vegetation Atmosphere Transfer) model, to account for soilatmosphere feedback mechanisms. After a validation was performed, MM5 was used as a regional climate model to simulated two 10-years time slices: 1991-2000 and 2030-2039. The emission scenario IS92a output of the global climate model ECHAM4 was downscaled dynamically, to a final resolution of 9km, for the Volta Basin. These regional climate simulations were then coupled to the physically based, distributed hydrological model WaSiM, after the calibration and adaptation of the hydrological model to the study region. A comparison the GCM output, as well as the RCM output for present-day climate simulation to observations showed a wet bias over the Sahel and a sufficient accuracy in temperature representation for the ECHAM4, present-day simulation (1961-1990). In the regional climate simulations, the displacement of the Inter Tropical Discontinuity (ITD) to the North at the beginning of the rainy season, as well as the displacement South, at the end occur too early. Rainfall also showed a negative deviation along the coast but a sufficient accuracy in the Volta Basin. The study demonstrates the ability of the coupled modelling system to reasonably simulate West African climate and hydrology conditions. For the selected scenario and time slices, the change signal in precipitation, as well as surface and subsurface hydrology variables lies with few exceptions

  13. Assessments for the impact of mineral dust on the meningitis incidence in West Africa

    Science.gov (United States)

    Martiny, Nadège; Chiapello, Isabelle

    2013-05-01

    Recently, mineral dust has been suspected to be one of the important environmental risk factor for meningitis epidemics in West Africa. The current study is one of the first which relies on long-term robust aerosol measurements in the Sahel region to investigate the possible impact of mineral dust on meningitis cases (incidence). Sunphotometer measurements, which allow to derive aerosol and humidity parameters, i.e., aerosol optical thickness, Angström coefficient, and precipitable water, are combined with quantitative epidemiological data in Niger and Mali over the 2004-2009 AMMA (African Monsoon Multidisciplinary Analysis) program period. We analyse how the extremely high aerosol loads in this region may influence both the calendar (onset, peaks, end) and the intensity of meningitis. We highlight three distinct periods: (i) from November to December, beginning of the dry season, humidity is weak, there is no dust and no meningitis cases; (ii) from January to April, humidity is still weak, but high dust loads occur in the atmosphere and this is the meningitis season; (iii) from May to October, humidity is high and there is no meningitis anymore, in presence of dust or not, which flow anyway in higher altitudes. More specifically, the onset of the meningitis season is tightly related to mineral dust flowing close to the surface at the very beginning of the year. During the dry, and the most dusty season period, from February to April, each meningitis peak is preceded by a dust peak, with a 0-2 week lead-time. The importance (duration, intensity) of these meningitis peaks seems to be related to that of dust, suggesting that a cumulative effect in dust events may be important for the meningitis incidence. This is not the case for humidity, confirming the special contribution of dust at this period of the year. The end of the meningitis season, in May, coincides with a change in humidity conditions related to the West African Monsoon. These results, which are

  14. Energy balance closure and footprint analysis using Eddy Covariance measurements in Eastern Burkina Faso, West Africa

    Directory of Open Access Journals (Sweden)

    F. Bagayoko

    2006-09-01

    Full Text Available The quality and the representativeness of the first long-term Eddy Covariance measurements in the savanna zone of West Africa were investigated using the energy balance closure and the footprint analysis. The quality and representativeness of the first long-term Eddy Covariance measurements over the West African savanna were investigated using the energy balance closure and the footprint analysis. The analysis covered four contrasting periods such as the complete dry season (January to March 2004, the dry to wet transition period (April to May 2004, the rainy season (June to September 2004 and the wet to dry transition period (October to November 2004.

    The results show that the overall energy balance closure can be considered as satisfactory over the whole dataset. The regression fit between (Rn−G and (H+λE was significant (P<0.05 with a coefficient of determination (r2 of 0.80 and a slope of 0.88, while the intercept was 25W/m2. The energy balance closure was affected by rain during the rainy season (r2=0.69, and by sampling problems during the transition periods (R2 were 0.80 and 0.86, respectively.

    The footprint analysis shows that the fetch ranged between 20 m (daytime and 800 m (nighttime. This range showed that the fetch was adequate and fluxes sampled were representative, especially during the rainy season when the vegetal cover was dominated by crops and grasses with scale length of a few meters. During the dry season when the surface is free from crops and grasses, the measurements were also representative as about 60% of the trees around the station were contributing to the measured fluxes. However, during the transition periods some sampling problems appeared, less than 30% of the trees were contributing to the measured fluxes. The relevance of the dominant wind direction in the representativeness of the measurements was also discussed.

  15. Parameter identification of the SWAT model on the BANI catchment (West Africa) under limited data condition

    Science.gov (United States)

    Chaibou Begou, Jamilatou; Jomaa, Seifeddine; Benabdallah, Sihem; Rode, Michael

    2015-04-01

    Due to the climate change, drier conditions have prevailed in West Africa, since the seventies, and the consequences are important on water resources. In order to identify and implement management strategies of adaptation to climate change in the sector of water, it is crucial to improve our physical understanding of water resources evolution in the region. To this end, hydrologic modelling is an appropriate tool for flow predictions under changing climate and land use conditions. In this study, the applicability and performance of the recent version of Soil and Water Assessment Tool (SWAT2012) model were tested on the Bani catchment in West Africa under limited data condition. Model parameters identification was also tested using one site and multisite calibration approaches. The Bani is located in the upper part of the Niger River and drains an area of about 101, 000 km2 at the outlet of Douna. The climate is tropical, humid to semi-arid from the South to the North with an average annual rainfall of 1050 mm (period 1981-2000). Global datasets were used for the model setup such as: USGS hydrosheds DEM, USGS LCI GlobCov2009 and the FAO Digital Soil Map of the World. Daily measured rainfall from nine rain gauges and maximum and minimum temperature from five weather stations covering the period 1981-1997 were used for model setup. Sensitivity analysis, calibration and validation are performed within SWATCUP using GLUE procedure at Douna station first (one site calibration), then at three additional internal stations, Bougouni, Pankourou and Kouoro1 (multi-site calibration). Model parameters were calibrated at daily time step for the period 1983-1992, then validated for the period 1993-1997. A period of two years (1981-1982) was used for model warming up. Results of one-site calibration showed that the model performance is evaluated by 0.76 and 0.79 for Nash-Sutcliffe (NS) and correlation coefficient (R2), respectively. While for the validation period the performance

  16. Sediment budget of cratons: insights from West Africa over the Cenozoic

    Science.gov (United States)

    Jean-Louis, G.; Chardon, D.; Rouby, D.; Beauvais, A.

    2015-12-01

    The sediment load of rivers constitutes the material that builds the stratigraphic successions found from continental margins to the deep ocean. Measure of this flux is relevant to understanding continental controls on denudation, riverine transport and basin filling. An increasing number of sediment yield measures is available but whether these modern values can be extrapolated at geological timescales for large watersheds is still questioned. One reason is the lack of long-term data. Here, we present a sediment budget for Sub-Saharan West Africa over the Cenozoic to compare with the modern rates. The denudation of this cratonic area is constrained using three regional lateritic paleo-landsurfaces that formed during periods of enhanced weathering since the Paleocene-Eocene greenhouse peak. The 3D interpolation of these surfaces allowed building three successive denudation maps for the 45-24, 24-11 and 11-0 Ma intervals together with reconstructions of the paleo-drainage. The regional distribution of erosion suggests the influence of lithospheric deformation, concentrated around a southern marginal upwarp and eastern hotspot swells. The export of large-scale drainages was calculated by converting denudated volumes into sediment fluxes using the porosity and density of lateritic regolith. Exported volumes calculated for the Niger watershed fall within the same range as the Cenozoic clastic accumulations of the Niger delta. Comparisons also show that modern fluxes can be an order of magnitude above the long-term fluxes for moderately large watersheds but that modern and long-term yields are similar for the largest watersheds (e.g. Niger, Volta, Senegal). These results suggest that the export of very large cratonic watersheds is independent of the measurement timescale and that their modern yields can be extrapolated at long-timescale. Finally, it allows assessing the relative contribution of cratons, i.e. non-active orogenic areas, to the global sediment budgets at

  17. How model and input uncertainty impact maize yield simulations in West Africa

    Science.gov (United States)

    Waha, Katharina; Huth, Neil; Carberry, Peter; Wang, Enli

    2015-02-01

    Crop models are common tools for simulating crop yields and crop production in studies on food security and global change. Various uncertainties however exist, not only in the model design and model parameters, but also and maybe even more important in soil, climate and management input data. We analyze the performance of the point-scale crop model APSIM and the global scale crop model LPJmL with different climate and soil conditions under different agricultural management in the low-input maize-growing areas of Burkina Faso, West Africa. We test the models’ response to different levels of input information from little to detailed information on soil, climate (1961-2000) and agricultural management and compare the models’ ability to represent the observed spatial (between locations) and temporal variability (between years) in crop yields. We found that the resolution of different soil, climate and management information influences the simulated crop yields in both models. However, the difference between models is larger than between input data and larger between simulations with different climate and management information than between simulations with different soil information. The observed spatial variability can be represented well from both models even with little information on soils and management but APSIM simulates a higher variation between single locations than LPJmL. The agreement of simulated and observed temporal variability is lower due to non-climatic factors e.g. investment in agricultural research and development between 1987 and 1991 in Burkina Faso which resulted in a doubling of maize yields. The findings of our study highlight the importance of scale and model choice and show that the most detailed input data does not necessarily improve model performance.

  18. [Organisation of Veterinary Services in the developing countries of West Africa].

    Science.gov (United States)

    Coulibaly, H

    2004-04-01

    The Veterinary Services in West Africa focused on animal health and production activities, which up until the beginning of the 1990s, were exclusively their responsibility. They were supported by many projects, conducted with notable successes. Veterinary public health activities were considered to be less of a priority because the major objective was improving productivity and because the concept of food safety was perceived by stakeholders to be much less important. The major challenges and issues that the weakened Veterinary Services will have to face are complying with the requirements of the World Trade Organization, negotiating new economic partnership agreements and dealing with the consequences of the implementation of structural adjustment programmes in the agricultural sector. The reorganisation of these Services is therefore taking place in the context of the globalisation of health problems, and in a trading framework that requires the application of the current international standards and regulations. Veterinary Services and their governments will have to meet these challenges by initiating discussions that lead to effective operational structures that can implement public health measures, satisfy the expectations of consumers and partner countries and withstand assessment by other countries. However, such reform depends upon several factors, such as a demonstration of political will, the development of an approach based on regional economic unions, and the indispensable support of financial backers. To add to the debate, the author offers recommendations and guidelines on the institutional framework, veterinary personnel and equipment and material needs. Creating effective Veterinary Services that have efficient operational structures and procedures is an ongoing process; how long this process takes depends on the ability of Veterinary Services to respond to the various challenges. Underlying these challenges and issues, in this region of the world as

  19. Temporal and spatial analysis of the 2014-2015 Ebola virus outbreak in West Africa.

    Science.gov (United States)

    Carroll, Miles W; Matthews, David A; Hiscox, Julian A; Elmore, Michael J; Pollakis, Georgios; Rambaut, Andrew; Hewson, Roger; García-Dorival, Isabel; Bore, Joseph Akoi; Koundouno, Raymond; Abdellati, Saïd; Afrough, Babak; Aiyepada, John; Akhilomen, Patience; Asogun, Danny; Atkinson, Barry; Badusche, Marlis; Bah, Amadou; Bate, Simon; Baumann, Jan; Becker, Dirk; Becker-Ziaja, Beate; Bocquin, Anne; Borremans, Benny; Bosworth, Andrew; Boettcher, Jan Peter; Cannas, Angela; Carletti, Fabrizio; Castilletti, Concetta; Clark, Simon; Colavita, Francesca; Diederich, Sandra; Donatus, Adomeh; Duraffour, Sophie; Ehichioya, Deborah; Ellerbrok, Heinz; Fernandez-Garcia, Maria Dolores; Fizet, Alexandra; Fleischmann, Erna; Gryseels, Sophie; Hermelink, Antje; Hinzmann, Julia; Hopf-Guevara, Ute; Ighodalo, Yemisi; Jameson, Lisa; Kelterbaum, Anne; Kis, Zoltan; Kloth, Stefan; Kohl, Claudia; Korva, Miša; Kraus, Annette; Kuisma, Eeva; Kurth, Andreas; Liedigk, Britta; Logue, Christopher H; Lüdtke, Anja; Maes, Piet; McCowen, James; Mély, Stéphane; Mertens, Marc; Meschi, Silvia; Meyer, Benjamin; Michel, Janine; Molkenthin, Peter; Muñoz-Fontela, César; Muth, Doreen; Newman, Edmund N C; Ngabo, Didier; Oestereich, Lisa; Okosun, Jennifer; Olokor, Thomas; Omiunu, Racheal; Omomoh, Emmanuel; Pallasch, Elisa; Pályi, Bernadett; Portmann, Jasmine; Pottage, Thomas; Pratt, Catherine; Priesnitz, Simone; Quartu, Serena; Rappe, Julie; Repits, Johanna; Richter, Martin; Rudolf, Martin; Sachse, Andreas; Schmidt, Kristina Maria; Schudt, Gordian; Strecker, Thomas; Thom, Ruth; Thomas, Stephen; Tobin, Ekaete; Tolley, Howard; Trautner, Jochen; Vermoesen, Tine; Vitoriano, Inês; Wagner, Matthias; Wolff, Svenja; Yue, Constanze; Capobianchi, Maria Rosaria; Kretschmer, Birte; Hall, Yper; Kenny, John G; Rickett, Natasha Y; Dudas, Gytis; Coltart, Cordelia E M; Kerber, Romy; Steer, Damien; Wright, Callum; Senyah, Francis; Keita, Sakoba; Drury, Patrick; Diallo, Boubacar; de Clerck, Hilde; Van Herp, Michel; Sprecher, Armand; Traore, Alexis; Diakite, Mandiou; Konde, Mandy Kader; Koivogui, Lamine; Magassouba, N'Faly; Avšič-Županc, Tatjana; Nitsche, Andreas; Strasser, Marc; Ippolito, Giuseppe; Becker, Stephan; Stoecker, Kilian; Gabriel, Martin; Raoul, Hervé; Di Caro, Antonino; Wölfel, Roman; Formenty, Pierre; Günther, Stephan

    2015-08-01

    West Africa is currently witnessing the most extensive Ebola virus (EBOV) outbreak so far recorded. Until now, there have been 27,013 reported cases and 11,134 deaths. The origin of the virus is thought to have been a zoonotic transmission from a bat to a two-year-old boy in December 2013 (ref. 2). From this index case the virus was spread by human-to-human contact throughout Guinea, Sierra Leone and Liberia. However, the origin of the particular virus in each country and time of transmission is not known and currently relies on epidemiological analysis, which may be unreliable owing to the difficulties of obtaining patient information. Here we trace the genetic evolution of EBOV in the current outbreak that has resulted in multiple lineages. Deep sequencing of 179 patient samples processed by the European Mobile Laboratory, the first diagnostics unit to be deployed to the epicentre of the outbreak in Guinea, reveals an epidemiological and evolutionary history of the epidemic from March 2014 to January 2015. Analysis of EBOV genome evolution has also benefited from a similar sequencing effort of patient samples from Sierra Leone. Our results confirm that the EBOV from Guinea moved into Sierra Leone, most likely in April or early May. The viruses of the Guinea/Sierra Leone lineage mixed around June/July 2014. Viral sequences covering August, September and October 2014 indicate that this lineage evolved independently within Guinea. These data can be used in conjunction with epidemiological information to test retrospectively the effectiveness of control measures, and provides an unprecedented window into the evolution of an ongoing viral haemorrhagic fever outbreak. PMID:26083749

  20. Dictating participation? Rethinking the adaptive co-management of socio-ecological systems in West Africa

    Science.gov (United States)

    El Vilaly, Audra; Abd salam El Vilaly, Mohamed

    2015-04-01

    In the face of environmental change, enhancing adaptive capacity relies on stakeholder engagement. But the participatory process, while critical to the translation, transfer, and application of scientific knowledge to society, is not without its own contradictions. These include the asymmetrical relations of power that prevail between environmental scientists, managers, and local users; discrepant understandings of knowledge and its appropriate uses; and conflicting social, economic, and ecological values, to name only a few. Our research examines five major transboundary river basin organizations in West Africa and their efforts to improve adaptive basin management via stakeholder collaboration. In particular, we evaluate the participatory strategies of these organizations to measure non-linear, multi-directional feedbacks between the social and biophysical factors of land use/land cover change, as well as the impacts of this change on basins and their dependent populations. Our research suggests that oftentimes, these methods paradoxically produce a hierarchical and marginalizing effect on local stakeholders in relation to the scientists that study them. In seeking to address these limitations, we assess the potential costs and benefits of integrating select components of a Participatory Action Research (PAR) framework (see, for example, Reason & Bradbury-Huang, 2007) into studies of complex socio-ecological problems. This approach, used widely in the social sciences, promotes critical reflection on and minimization of the power inequities inherent in science-society collaborations. It instead favors more horizontal forms of knowledge co-production that support and foster the expansion of local, existing movements for social and environmental justice. A PAR framework may therefore improve the efficiency, sustainability, and equitability of land-based adaptation to environmental change; further research is thus recommended to test this hypothesis. References

  1. The influence of woody thickening on SOM dynamics along a precipitation gradient in West Africa

    Science.gov (United States)

    Saiz, Gustavo; Bird, Michael; Wurster, Christopher; Ascough, Philippa; Veenendaal, Elmar; Butterbach-Bahl, Klaus; Schrodt, Franziska; Domingues, Tomas; Feldpausch, Ted; Braojos, Victor; Lloyd, Jonathan

    2014-05-01

    We made use of the carbon isotopic composition of soil organic matter (SOM) in bulk and fractionated samples to assess the influence of C3/C4 vegetation on SOM dynamics in semi-natural tropical ecosystems sampled along a precipitation gradient in West Africa. The non-linear nature of the relationship between δ13C and SOC content observed across the latitudinal gradient strongly suggests that in addition to the inherent differences in the input rates and turnover times of tree and grass-derived carbon, the broad range of edaphic characteristics may have a major effect in both the physical protection of particulate organic carbon and the chemical stabilization of 13C enriched microbial metabolites. The stable carbon isotopic composition of SOM with depth indicated that there was a larger proliferation in woody vegetation with increasing precipitation, with such trend being also heavily dependent on the characteristics of the soils. An unbiased assessment of the potential impact of tropical vegetation thickening on SOM dynamics is characteristically difficult given the confounding effects posed by the interaction of varying climatic and edaphic factors. Therefore, in order to minimize the impact of those factors, we selected two neighboring transitional ecosystems (a closed savanna woodland and a semideciduous dry forest) occurring in soils of comparable characteristics. Both sites showed varying degrees of δ13C enrichment with depth in bulk and fractionated SOM. Moreover, radiocarbon analyses of sand-size aggregates (>53 μm HF) yielded relatively short MRT, which shows highly dynamic SOM processes even in fairly deep locations. Interestingly, the most stable SOM fraction associated to silt and clay (

  2. The geology and geochemistry of some epigenetic uranium deposits near the Swakop River, South West Africa

    International Nuclear Information System (INIS)

    This study comprises a geological and geochemical investigation of the uranium deposits in the region near the Swakop River which extends from the Langer Heinrich Mountain in the east to the end of the Tumas River in the west. The general geology of the basement rocks in the Langer Heinrich region only is discussed. The general geology of the younger duricrust formations is discussed. Analytical methods were developed for the separation of thorium, protactinium and uranium from geological materials using various chromatographic procedures. Alpha spectrometry, neutron activation analysis and delayed neutron counting were the main techniques used. The occurrence of uranium in the region of study follows a unique geochemical cycle, and the geochemistry at each stage in the cycle was examined. The first stage in the uranium-geochemical cycle was the basement rocks. The second stage in the geochemical cycle of uranium was the subsurface water. The third stage in the geochemical cycle of uranium concerns its occurrence in the duricrust deposits. Isotopic disequilibrium measurements showed that uranium is still migrating, and that the age of the carnotite precipitation is 30 000 years, based on the open-system model of uranium migration. In the final stage of the geochemical cycle, the geochemistry of uranium in seawater and the diatomaceous muds is discussed. A classification system for the uranium deposits near the Swakop River, based on genetic relationships, is proposed and described in terms of the geochemical cycle of uranium, the mode of transport and mode of deposition. The relationships between the duricrust uranium deposits and the other uranium deposits of South Africa are compared

  3. Calculating crop water requirement satisfaction in the West Africa Sahel with remotely sensed soil moisture

    Science.gov (United States)

    McNally, Amy; Gregory J. Husak; Molly Brown; Mark Carroll; Funk, Christopher C.; Soni Yatheendradas; Kristi Arsenault; Christa Peters-Lidard; Verdin, James

    2015-01-01

    The Soil Moisture Active Passive (SMAP) mission will provide soil moisture data with unprecedented accuracy, resolution, and coverage, enabling models to better track agricultural drought and estimate yields. In turn, this information can be used to shape policy related to food and water from commodity markets to humanitarian relief efforts. New data alone, however, do not translate to improvements in drought and yield forecasts. New tools will be needed to transform SMAP data into agriculturally meaningful products. The objective of this study is to evaluate the possibility and efficiency of replacing the rainfall-derived soil moisture component of a crop water stress index with SMAP data. The approach is demonstrated with 0.1°-resolution, ~10-day microwave soil moisture from the European Space Agency and simulated soil moisture from the Famine Early Warning Systems Network Land Data Assimilation System. Over a West Africa domain, the approach is evaluated by comparing the different soil moisture estimates and their resulting Water Requirement Satisfaction Index values from 2000 to 2010. This study highlights how the ensemble of indices performs during wet versus dry years, over different land-cover types, and the correlation with national-level millet yields. The new approach is a feasible and useful way to quantitatively assess how satellite-derived rainfall and soil moisture track agricultural water deficits. Given the importance of soil moisture in many applications, ranging from agriculture to public health to fire, this study should inspire other modeling communities to reformulate existing tools to take advantage of SMAP data.

  4. Ebola or Not? Evaluating the Ill Traveler From Ebola-Affected Countries in West Africa.

    Science.gov (United States)

    Fairley, Jessica K; Kozarsky, Phyllis E; Kraft, Colleen S; Guarner, Jeannette; Steinberg, James P; Anderson, Evan; Jacob, Jesse T; Meloy, Patrick; Gillespie, Darria; Espinoza, Tamara R; Isakov, Alexander; Vanairsdale, Sharon; Baker, Esther; Wu, Henry M

    2016-01-01

    Background.  The 2014-2015 Ebola epidemic in West Africa had global impact beyond the primarily affected countries of Guinea, Liberia, and Sierra Leone. Other countries, including the United States, encountered numerous patients who arrived from highly affected countries with fever or other signs or symptoms consistent with Ebola virus disease (EVD). Methods.  We describe our experience evaluating 25 travelers who met the US Centers for Disease Control and Prevention case definition for a person under investigation (PUI) for EVD from July 20, 2014 to January 28, 2015. All patients were triaged and evaluated under the guidance of institutional protocols to the emergency department, outpatient tropical medicine clinic, or Emory's Ebola treatment unit. Strict attention to infection control and early involvement of public health authorities guided the safe evaluation of these patients. Results.  None were diagnosed with EVD. Respiratory illnesses were common, and 8 (32%) PUI were confirmed to have influenza. Four patients (16%) were diagnosed with potentially life-threatening infections or conditions, including 3 with Plasmodium falciparum malaria and 1 with diabetic ketoacidosis. Conclusions.  In addition to preparing for potential patients with EVD, Ebola assessment centers should consider other life-threatening conditions requiring urgent treatment, and travelers to affected countries should be strongly advised to seek pretravel counseling. Furthermore, attention to infection control in all aspects of PUI evaluation is paramount and has presented unique challenges. Lessons learned from our evaluation of potential patients with EVD can help inform preparations for future outbreaks of highly pathogenic communicable diseases. PMID:26925428

  5. The Impact of the West Africa Ebola Outbreak on Obstetric Health Care in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Kim J Brolin Ribacke

    Full Text Available As Sierra Leone celebrates the end of the Ebola Virus Disease (EVD outbreak, we can begin to fully grasp its impact on already weak health systems. The EVD outbreak in West Africa forced many hospitals to close down or reduce their activity, either to prevent nosocomial transmission or because of staff shortages. The aim of this study is to assess the potential impact of EVD on nationwide access to obstetric care in Sierra Leone.Community health officers collected weekly data between January 2014-May 2015 on in-hospital deliveries and caesarean sections (C-sections from all open facilities (public, private for-profit and private non-profit sectors offering emergency obstetrics in Sierra Leone. This was compared to official data of EVD cases per district. Logistic and Poisson regression analyses were used to compute risk and rate estimates. Nationwide, the number of in-hospital deliveries and C-sections decreased by over 20% during the EVD outbreak. The decline occurred early on in the EVD outbreak and was mainly attributable to the closing of private not-for-profit hospitals rather than government facilities. Due to difficulties in collecting data in the midst of an epidemic, limitations of this study include some missing data points.Both the number of in-hospital deliveries and C-sections substantially declined shortly after the onset of the EVD outbreak. Since access to emergency obstetric care, like C-sections, is associated with decreased maternal mortality, many women are likely to have died due to the reduced access to appropriate care during childbirth. Future research on indirect health effects of health system breakdown should ideally be nationwide and continue also into the recovery phase. It is also important to understand the mechanisms behind the deterioration so that important health services can be reestablished.

  6. Optimal feeding systems for small-scale dairy herds in the North West Province, South Africa

    Directory of Open Access Journals (Sweden)

    N. Patience Manzana

    2014-02-01

    Full Text Available Land redistribution was legislated in 1994; it was designed to resolve historical imbalances inland ownership in South Africa. Between 2002 and 2006, a longitudinal observational studywas conducted with 15 purposively selected small-scale dairy farmers in a land redistributionproject in Central North West Province. Four farmers left the project over the period. For thepurposes of this study, a small-scale dairy farm was defined as a farm that produces less than500 L of milk a day, irrespective of the number of cows or size of the farm. The study wasconducted in three phases. In the first phase, situational analysis using participatory ruralappraisal (PRA and observation was used to outline the extent of the constraints and designappropriate interventions. Feeds that were used were tested and evaluated. In the secondphase, three different feeding systems were designed from the data obtained from PRA. Thesewere: (1 A semi-intensive farm-based ration using available crops, pastures and crop residueswith minimal rations purchased. (2 An intensive, zero-grazing dairy system using a totalmixed ration. (3 A traditional, extensive or dual-purpose system, where the calf drank fromthe cow until weaning and milking was done only once a day. In the third phase, adoptionwas monitored. By July 2006, all remaining farmers had changed to commercially formulatedrations or licks and the body condition score of the cows had improved. It was concluded thatveterinary extension based on PRA and a holistic systems approach was a good option forsuch complex problems. Mentoring by commercial dairy farmers, veterinary and extensionservices appeared to be viable. Further research should be done to optimise the traditionalmodel of dairy farming, as this was relatively profitable, had a lower risk and was less labourintensive.

  7. Characteristics of Droughts in South Africa: A Case Study of Free State and North West Provinces

    Directory of Open Access Journals (Sweden)

    Christina M. Botai

    2016-10-01

    Full Text Available The Free State (FS and North West (NW Provinces are often hard hit by droughts with impacts on water availability, farm production and livestock holdings. The South African government declared the two Provinces drought disaster areas in the 2015/2016 hydrological year. This is a major drawback, since both the Provinces play an important role to South African economy as they are a haven to agricultural production and have major water reservoirs in South Africa. This study was undertaken to investigate the historical evolution of drought within the FS and NW Provinces over the past 30 years. The Standardized Precipitation Index (SPI and Standardized Precipitation Evapotranspiration Index (SPEI calculated based on monthly meteorological data from 14 weather/climate stations within the FS and NW Provinces were used to explore and characterize variation in drought intensity, duration, frequency and severity in FS and NW Provinces during 1985–2015. Results indicate that there exist localized positive and negative trends with spatial dependence across the selected stations. In particular, about 60% of the weather stations exhibiting a decreasing trend are located in FS Province, suggesting that FS has being experiencing increasing drought during the analyzed period compared to NW Province. Results from the analysis of drought evaluation indicators (DEIs calculated from SPEI suggest that drought severity and frequency was more pronounced in FS while the intensity of the drought was more in NW Province during 1985–2015. In addition, based on SPEI calculations, moderate drought occurrences increased during 1985–1994 and 1995–2004 periods and decreased thereafter (2005–2015 in both Provinces. Drought classification based on parameters derived from SPEI produced similar results for mild drought occurrences during the same time scales.

  8. Overview of main challenges for Early Warning Systems for Food Security in West Africa

    Science.gov (United States)

    Genesio, Lorenzo; Bacci, Maurizio; Baron, Christian; Diarra, Birama; di Vecchia, Andrea; Traoré, Seydou; Hassane, Idrissa; Ndiaye, Mamadou; Philippon, Nathalie; Tarchiani, Vieri

    2010-05-01

    In West Africa Early Warning Systems (EWSs) for food security have been widely recognized to have contributed in the last twenty years to better face famine emergencies. The improved understanding of the environmental and socio-economic dynamics of the region, a change in the causes for food insecurity and the evolution of Information and Communication Technologies (ICT) have favored the introduction of new approaches and the involvement of a network of stakeholders. In recent years the improvement of EWS has been concentrated in the adaptation and the transfer of existing tools rather than the development of the overall design of EWS in function of users needs, at the same time key scientific areas to be improved to provide major operational advancements needs to be better identified. This partially due to a difficulty of the research community to be in direct connection with operational processes and on the other side by an evident limit in following a demand driven approach due to the difficulties in modelling bio and social phenomena in a unique environment. In this context AMMA project had the ambitious objective of bridging the gap between state of the art research in the domains of geo-science and human related disciplines, and the operational EWS. The work carried out in AMMA, while improving the understanding of monsoon system, allowed to better orient research challenges in order to provide EWS with improved products effectively meeting the needs of end-users at different levels. In this work, advancements in providing appropriate information for the identification of agricultural risk zones by using short to long time forecasts are illustrated highlighting critical aspects still demanding scientific improvements.

  9. Ebola or Not? Evaluating the Ill Traveler From Ebola-Affected Countries in West Africa

    Science.gov (United States)

    Fairley, Jessica K.; Kozarsky, Phyllis E.; Kraft, Colleen S.; Guarner, Jeannette; Steinberg, James P.; Anderson, Evan; Jacob, Jesse T.; Meloy, Patrick; Gillespie, Darria; Espinoza, Tamara R.; Isakov, Alexander; Vanairsdale, Sharon; Baker, Esther; Wu, Henry M.

    2016-01-01

    Background. The 2014–2015 Ebola epidemic in West Africa had global impact beyond the primarily affected countries of Guinea, Liberia, and Sierra Leone. Other countries, including the United States, encountered numerous patients who arrived from highly affected countries with fever or other signs or symptoms consistent with Ebola virus disease (EVD). Methods. We describe our experience evaluating 25 travelers who met the US Centers for Disease Control and Prevention case definition for a person under investigation (PUI) for EVD from July 20, 2014 to January 28, 2015. All patients were triaged and evaluated under the guidance of institutional protocols to the emergency department, outpatient tropical medicine clinic, or Emory's Ebola treatment unit. Strict attention to infection control and early involvement of public health authorities guided the safe evaluation of these patients. Results. None were diagnosed with EVD. Respiratory illnesses were common, and 8 (32%) PUI were confirmed to have influenza. Four patients (16%) were diagnosed with potentially life-threatening infections or conditions, including 3 with Plasmodium falciparum malaria and 1 with diabetic ketoacidosis. Conclusions. In addition to preparing for potential patients with EVD, Ebola assessment centers should consider other life-threatening conditions requiring urgent treatment, and travelers to affected countries should be strongly advised to seek pretravel counseling. Furthermore, attention to infection control in all aspects of PUI evaluation is paramount and has presented unique challenges. Lessons learned from our evaluation of potential patients with EVD can help inform preparations for future outbreaks of highly pathogenic communicable diseases. PMID:26925428

  10. Stabilization of large drainage basins over geological time scales: Cenozoic West Africa, hot spot swell growth, and the Niger River

    Science.gov (United States)

    Chardon, Dominique; Grimaud, Jean-Louis; Rouby, Delphine; Beauvais, Anicet; Christophoul, Frédéric

    2016-03-01

    Reconstructing the evolving geometry of large river catchments over geological time scales is crucial to constraining yields to sedimentary basins. In the case of Africa, it should further help deciphering the response of large cratonic sediment routing systems to Cenozoic growth of the basin-and-swell topography of the continent. Mapping of dated and regionally correlated lateritic paleolandscape remnants complemented by onshore sedimentological archives allows the reconstruction of two physiographic configurations of West Africa in the Paleogene. Those reconstructions show that the geometry of the drainage is stabilized by the late early Oligocene (29 Ma) and probably by the end of the Eocene (34 Ma), allowing to effectively link the inland morphoclimatic record to offshore sedimentation since that time, particularly in the case of the Niger catchment—delta system. Mid-Eocene paleogeography reveals the antiquity of the Senegambia catchment back to at least 45 Ma and suggests that a marginal upwarp forming a continental divide preexisted early Oligocene connection of the Niger and Volta catchments to the Equatorial Atlantic Ocean. Such a drainage rearrangement was primarily enhanced by the topographic growth of the Hoggar hot spot swell and caused a stratigraphic turnover along the Equatorial margin of West Africa.

  11. The Foraging Ecology of the Endangered Cape Verde Shearwater, a Sentinel Species for Marine Conservation off West Africa.

    Science.gov (United States)

    Paiva, Vitor H; Geraldes, Pedro; Rodrigues, Isabel; Melo, Tommy; Melo, José; Ramos, Jaime A

    2015-01-01

    Large Marine Ecosystems such as the Canary Current system off West Africa sustains high abundance of small pelagic prey, which attracts marine predators. Seabirds are top predators often used as biodiversity surrogates and sentinel species of the marine ecosystem health, thus frequently informing marine conservation planning. This study presents the first data on the spatial (GPS-loggers) and trophic (stable isotope analysis) ecology of a tropical seabird-the endangered Cape Verde shearwater Calonectris edwardsii-during both the incubation and the chick-rearing periods of two consecutive years. This information was related with marine environmental predictors (species distribution models), existent areas of conservation concern for seabirds (i.e. marine Important Bird Areas; marine IBAs) and threats to the marine environment in the West African areas heavily used by the shearwaters. There was an apparent inter-annual consistency on the spatial, foraging and trophic ecology of Cape Verde shearwater, but a strong alteration on the foraging strategies of adult breeders among breeding phases (i.e. from incubation to chick-rearing). During incubation, birds mostly targeted a discrete region off West Africa, known by its enhanced productivity profile and thus also highly exploited by international industrial fishery fleets. When chick-rearing, adults exploited the comparatively less productive tropical environment within the islands of Cape Verde, at relatively close distance from their breeding colony. The species enlarged its trophic niche and increased the trophic level of their prey from incubation to chick-rearing, likely to provision their chicks with a more diversified and better quality diet. There was a high overlap between the Cape Verde shearwaters foraging areas with those of European shearwater species that overwinter in this area and known areas of megafauna bycatch off West Africa, but very little overlap with existing Marine Important Bird Areas. Further

  12. The Foraging Ecology of the Endangered Cape Verde Shearwater, a Sentinel Species for Marine Conservation off West Africa.

    Directory of Open Access Journals (Sweden)

    Vitor H Paiva

    Full Text Available Large Marine Ecosystems such as the Canary Current system off West Africa sustains high abundance of small pelagic prey, which attracts marine predators. Seabirds are top predators often used as biodiversity surrogates and sentinel species of the marine ecosystem health, thus frequently informing marine conservation planning. This study presents the first data on the spatial (GPS-loggers and trophic (stable isotope analysis ecology of a tropical seabird-the endangered Cape Verde shearwater Calonectris edwardsii-during both the incubation and the chick-rearing periods of two consecutive years. This information was related with marine environmental predictors (species distribution models, existent areas of conservation concern for seabirds (i.e. marine Important Bird Areas; marine IBAs and threats to the marine environment in the West African areas heavily used by the shearwaters. There was an apparent inter-annual consistency on the spatial, foraging and trophic ecology of Cape Verde shearwater, but a strong alteration on the foraging strategies of adult breeders among breeding phases (i.e. from incubation to chick-rearing. During incubation, birds mostly targeted a discrete region off West Africa, known by its enhanced productivity profile and thus also highly exploited by international industrial fishery fleets. When chick-rearing, adults exploited the comparatively less productive tropical environment within the islands of Cape Verde, at relatively close distance from their breeding colony. The species enlarged its trophic niche and increased the trophic level of their prey from incubation to chick-rearing, likely to provision their chicks with a more diversified and better quality diet. There was a high overlap between the Cape Verde shearwaters foraging areas with those of European shearwater species that overwinter in this area and known areas of megafauna bycatch off West Africa, but very little overlap with existing Marine Important Bird

  13. Seismic architecture and morphology of Neogenic sediment waves and drifts, offshore West Africa

    Science.gov (United States)

    Baglioni, Luca; Bonamini, Enrico

    2013-04-01

    fill SW troughs. The positive relief of wave crests guided sediment gravity flows, inducing erosion and deposition focused along wave troughs. The shallower interval is fully dominated by bottom current deposits. A succession of SW around 300 ms thick covers the central-eastern sector of the study area. The described SW field is about 5 km wide and continuous over a distance of 30 km, and the average wavelength between two crests is 2 km. It is connected updip with a time equivalent rectilinear canyon-shaped erosive feature, whose genetic relation with the SW is now matter of discussion. The presence of upslope migrating SW indicates deposition by bottom current flowing upslope, under the influence of the Coriolis force. Such landwards-directed bottom currents on the slope probably represent the still active South-East Atlantic Upwelling, which has been present along the West Africa margin throughout the Neogene.

  14. The 2014 Ebola virus outbreak in West Africa highlights no evidence of rapid evolution or adaptation to humans

    Science.gov (United States)

    Li, Xingguang; Zai, Junjie; Liu, Haizhou; Feng, Yi; Li, Fan; Wei, Jing; Zou, Sen; Yuan, Zhiming; Shao, Yiming

    2016-01-01

    Following its immergence in December 2013, the recent Zaire Ebola virus (EBOV) outbreak in West Africa has spread and persisted for more than two years, making it the largest EBOV epidemic in both scale and geographical region to date. In this study, a total of 726 glycoprotein (GP) gene sequences of the EBOV full-length genome obtained from West Africa from the 2014 outbreak, combined with 30 from earlier outbreaks between 1976 and 2008 were used to investigate the genetic divergence, evolutionary history, population dynamics, and selection pressure of EBOV among distinct epidemic waves. Results from our dataset showed that no non-synonymous substitutions occurred on the GP gene coding sequences of EBOV that were likely to have affected protein structure or function in any way. Furthermore, the significantly different dN/dS ratios observed between the 2014 West African outbreak and earlier outbreaks were more likely due to the confounding presence of segregating polymorphisms. Our results highlight no robust evidence that the 2014 EBOV outbreak is fast-evolving and adapting to humans. Therefore, the unprecedented nature of the 2014 EBOV outbreak might be more likely related to non-virological elements, such as environmental and sociological factors. PMID:27767073

  15. West African colonial civil servants in the nineteenth century : African participation in British colonial expansion in West Africa

    NARCIS (Netherlands)

    Arhin, K.

    1985-01-01

    From the 1850's to mid 1890's Africans were employed in top positions in the embryonic West African colonial services. This book contains the biographies of three of them: Ferguson on the Gold Coast, Lawson in Sierra Leone and Payne in Nigeria. All three had in common that they believed in British r

  16. Conservation of soil organic carbon, biodiversity and the provision of other ecosystem services along climatic gradients in West Africa

    Science.gov (United States)

    Marks, E.; Aflakpui, G. K. S.; Nkem, J.; Poch, R. M.; Khouma, M.; Kokou, K.; Sagoe, R.; Sebastiã, M.-T.

    2009-08-01

    Terrestrial carbon resources are major drivers of development in West Africa. The distribution of these resources co-varies with ecosystem type and rainfall along a strong Northeast-Southwest climatic gradient. Soil organic carbon, a strong indicator of soil quality, has been severely depleted in some areas by human activities, which leads to issues of soil erosion and desertification, but this trend can be altered with appropriate management. There is significant potential to enhance existing soil carbon stores in West Africa, with benefits at the global and local scale, for atmospheric CO2 mitigation as well as supporting and provisioning ecosystem services. Three key factors impacting carbon stocks are addressed in this review: climate, biotic factors, and human activities. Climate risks must be considered in a framework of global change, especially in West Africa, where landscape managers have few resources available to adapt to climatic perturbations. Among biotic factors, biodiversity conservation paired with carbon conservation may provide a pathway to sustainable development, and biodiversity conservation is also a global priority with local benefits for ecosystem resilience, biomass productivity, and provisioning services such as foodstuffs. Finally, human management has largely been responsible for reduced carbon stocks, but this trend can be reversed through the implementation of appropriate carbon conservation strategies in the agricultural sector, as shown by multiple studies. Owing to the strong regional climatic gradient, country-level initiatives will need to consider carbon sequestration approaches for multiple ecosystem types. Given the diversity of environments, global policies must be adapted and strategies developed at the national or sub-national levels to improve carbon storage above and belowground. Initiatives of this sort must act locally at farmer scale, and focus on ecosystem services rather than on carbon sequestration solely.

  17. Conservation of soil organic carbon, biodiversity and the provision of other ecosystem services along climatic gradients in West Africa

    Directory of Open Access Journals (Sweden)

    E. Marks

    2008-11-01

    Full Text Available Terrestrial carbon resources are major drivers of development in West Africa. The distribution of these resources co-varies with ecosystem type and rainfall along a strong Northeast-Southwest climatic gradient. Soil organic carbon, a strong indicator of soil quality, has been severely depleted in some areas by human activities, which leads to issues of soil erosion and desertification, but this trend can be altered via appropriate management. There is significant potential to enhance existing soil carbon stores in West Africa, with benefits at the global and local scales, for atmospheric CO2 mitigation and supporting, and provisioning ecosystem services, respectively. Three key factors impacting carbon stocks are addressed in this review: climate, biotic factors, and human activities. Climate risks must be considered in a framework of global change, especially in West Africa, where landscape managers have few resources available to adapt to climatic perturbations. Among biotic factors, biodiversity conservation paired with carbon conservation may provide a pathway to sustainable development, as evidence suggests that both may be inter-linked, and biodiversity conservation is also a global priority with local benefits for ecosystem resilience, biomass productivity, and provisioning services such as foodstuffs. Finally, human management has largely been responsible for reduced carbon stocks, but this trend can be reversed through the implementation of appropriate carbon conservation strategies in the agricultural sector, as shown by multiple studies. Owing to the strong regional climatic gradient, country-level initiatives will need to consider carbon sequestration approaches for multiple ecosystem types. Given the diversity of environments, global policies must be adapted and strategised at the national or sub-national levels to improve C storage above and belowground. Initiatives of this sort must act locally at farmer scale, and

  18. West Africa Extreme Rainfall Events and Large-Scale Ocean Surface and Atmospheric Conditions in the Tropical Atlantic

    Directory of Open Access Journals (Sweden)

    S. Ta

    2016-01-01

    Full Text Available Based on daily precipitation from the Global Precipitation Climatology Project (GPCP data during April–October of the 1997–2014 period, the daily extreme rainfall trends and variability over West Africa are characterized using 90th-percentile threshold at each grid point. The contribution of the extreme rainfall amount reaches ~50–90% in the northern region while it is ~30–50% in the south. The yearly cumulated extreme rainfall amount indicates significant and negative trends in the 6°N–12°N; 6°N–12°N; 17°W–10°W and 4°N–7°N; 4°N–7°N; 6°E–10°E 4°N–7°N; 6°E–10°E 4°N–7°N; 6°E–10°E domains, while the number of days exhibits nonsignificant trends over West Africa. The empirical orthogonal functions performed on the standardized anomalies show four variability modes that include all West Africa with a focus on the Sahelian region, the eastern region including the south of Nigeria, the western part including Guinea, Sierra Leone, Liberia, and Guinea-Bissau, and finally a small region at the coast of Ghana and Togo. These four modes are influenced differently by the large-scale ocean surface and atmospheric conditions in the tropical Atlantic. The results are applicable in planning the risks associated with these climate hazards, particularly on water resource management and civil defense.

  19. Using Seasonal Climate Forecasts to Guide Disaster Management: The Red Cross Experience during the 2008 West Africa Floods

    Directory of Open Access Journals (Sweden)

    Arame Tall

    2012-01-01

    Full Text Available In 2008, the seasonal forecast issued at the Seasonal Climate Outlook Forum for West Africa (PRESAO announced a high risk of above-normal rainfall for the July–September rainy season. With probabilities for above-normal rainfall of 0.45, this forecast indicated noteworthy increases in the risk of heavy rainfall. When this information reached the International Federation of Red Cross and Red Crescent Societies (IFRC West and Central Africa Office, it led to significant changes in the organization’s flood response operations. The IFRC regional office requested funds in advance of anticipated floods, prepositioned disaster relief items in strategic locations across West Africa to benefit up to 9,500 families, updated its flood contingency plans, and alerted vulnerable communities and decision-makers across the region. This forecast-based preparedness resulted in a decrease in the number of lives, property, and livelihoods lost to floods, compared to just one year prior in 2007 when similar floods claimed above 300 lives in the region. This article demonstrates how a science-based early warning informed decisions and saved lives by triggering action in anticipation of forecast events. It analyses what it took to move decision-makers to action, based on seasonal climate information, and to overcome traditional barriers to the uptake of seasonal climate information in the region, providing evidence that these barriers can be overcome. While some institutional, communication and technical barriers were addressed in 2008, many challenges remain. Scientists and humanitarians need to build more common ground.

  20. Marine communities on oil platforms in Gabon, West Africa: high biodiversity oases in a low biodiversity environment.

    Science.gov (United States)

    Friedlander, Alan M; Ballesteros, Enric; Fay, Michael; Sala, Enric

    2014-01-01

    The marine biodiversity of Gabon, West Africa has not been well studied and is largely unknown. Our examination of marine communities associated with oil platforms in Gabon is the first scientific investigation of these structures and highlights the unique ecosystems associated with them. A number of species previously unknown to Gabonese waters were recorded during our surveys on these platforms. Clear distinctions in benthic communities were observed between older, larger platforms in the north and newer platforms to the south or closer to shore. The former were dominated by a solitary cup coral, Tubastraea sp., whereas the latter were dominated by the barnacle Megabalanus tintinnabulum, but with more diverse benthic assemblages compared to the northerly platforms. Previous work documented the presence of limited zooxanthellated scleractinian corals on natural rocky substrate in Gabon but none were recorded on platforms. Total estimated fish biomass on these platforms exceeded one ton at some locations and was dominated by barracuda (Sphyraena spp.), jacks (Carangids), and rainbow runner (Elagatis bipinnulata). Thirty-four percent of fish species observed on these platforms are new records for Gabon and 6% are new to tropical West Africa. Fish assemblages closely associated with platforms had distinct amphi-Atlantic affinities and platforms likely extend the distribution of these species into coastal West Africa. At least one potential invasive species, the snowflake coral (Carijoa riisei), was observed on the platforms. Oil platforms may act as stepping stones, increasing regional biodiversity and production but they may also be vectors for invasive species. Gabon is a world leader in terrestrial conservation with a network of protected areas covering >10% of the country. Oil exploration and biodiversity conservation currently co-exist in terrestrial and freshwater ecosystems in Gabon. Efforts to increase marine protection in Gabon may benefit by including oil

  1. Reflections on the Upheaval of West Asia and North Africa%西亚北非变局的反思

    Institute of Scientific and Technical Information of China (English)

    刘小勤

    2011-01-01

    Political unrests triggered in the countries in West Asia and North Africa are neither unexpected events,nor "endogenous events" declared by some scholars in an early period.It results from the conflicts in the political,economic,and social development of the countries in West Asia and north Africa,and the outside inducement of the Middle East reforming policy and the network diplomacy propelled by The United States and other western countries.It is an all-round social oscillation intertwined with internal and external factors.Reflections on West Asia and North Africa upheavals have deep enlightenments on the social and economic development of the developing countries,including our country.%引发西亚北非等国的政治动荡并不是偶然的突发性事件,也不是一些学者在早期所断言的"内生性事件",究其原因,有西亚北非国家自身政治、经济、社会发展矛盾的集中凸显,也有美国等西方国家推行改造中东、推行网络外交的外部诱因,是一场内外因素相互交织、综合作用下的社会全面动荡。西亚北非变局对于包括我国在内的发展中国家的社会经济发展具有深刻的启示。

  2. The influences of cropping systems on weed communities of rice in Côte d'Ivoire, West Africa

    OpenAIRE

    Kent, R.; Johnson, D E; Becker, M

    2001-01-01

    In West Africa agricultural land use for rice production is changing rapidly with increased cropping intensity in some areas. Studies were conducted to examine how the different cropping systems are reflected in rice weed populations. Weed species were surveyed on 126 rice farms in the humid forest to the moist savannah zones of Côte d'Ivoire. Two additional surveys were undertaken in a peri-urban area of the savannah zone to examine the effects water control and cropping diversification on w...

  3. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation, challenges, and way forward

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2014-01-01

    Full Text Available Background: There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. Objective: This study was conducted to provide baseline data on university-level nutrition training programs that exist in the 16 countries in West Africa. It also aimed to identify existing gaps in nutrition training and propose solutions to address them. Design: Participating institutions were identified based on information provided by in-country key informants, UNICEF offices or through internet searches. Data were collected through semi-structured interviews during on-site visits or through self-administered questionnaires. Simple descriptive and bivariate analyses were performed. Results: In total, 83 nutrition degree programs comprising 32 B.Sc. programs, 34 M.Sc. programs, and 17 Ph.D. programs were identified in the region. More than half of these programs were in Nigeria. Six countries (Cape Verde, Guinea-Bissau, Liberia, Mali, The Gambia, and Togo offered no nutrition degree program. The programs in francophone countries were generally established more recently than those in anglophone countries (age: 3.5 years vs. 21.4 years. Programs were predominantly (78% run by government-supported institutions. They did not provide a comprehensive coverage of all essential aspects of human nutrition. They were heavily oriented to food science (46%, with little emphasis on public health nutrition (24% or overnutrition (2%. Annual student intakes per program in 2013 ranged from 3 to 262; 7 to 40; and 3 to 10, respectively, for bachelor's, master's, and doctoral programs while the number of graduates produced annually per country ranged from 6 to 271; 3 to 64; and 1 to 18, respectively. External collaboration only existed in 15% of the programs. In-service training programs on

  4. The prevalence of helminth and arthropod parasites of warthog, Phacochoerus aethiopicus, in South West Africa/Namibia.

    Science.gov (United States)

    Horak, I G; Biggs, H C; Hanssen, T S; Hanssen, R E

    1983-06-01

    A total of 38 warthog, Phacochoerus aethiopicus, shot on a farm in northern South West Africa/Namibia were examined for internal and external parasites at monthly intervals over a period of 13 months. They harboured cestodes, 9 nematode species, 6 ixodid tick species and 1 species each of an argasid tick, a flea, a louse and larvae of a dipteran fly. Clear patterns of seasonal abundance could be determined only for the spirurid stomach worm, Physocephalus sexalatus, and the sucking louse, Haematopinus phachoeri. PMID:6634088

  5. The Sahel Region of West Africa: Examples of Climate Analyses Motivated By Drought Management Needs

    Science.gov (United States)

    Ndiaye, O.; Ward, M. N.; Siebert, A. B.

    2011-12-01

    The Sahel is one of the most drought-prone regions in the world. This paper focuses on climate sources of drought, and some new analyses mostly driven by users needing climate information to help in drought management strategies. The Sahel region of West Africa is a transition zone between equatorial climate and vegetation to the south, and desert to the north. The climatology of the region is dominated by dry conditions for most of the year, with a single peak in rainfall during boreal summer. The seasonal rainfall total contains both interannual variability and substantial decadal to multidecadal variability (MDV). This brings climate analysis and drought management challenges across this range of timescales. The decline in rainfall from the wet decades of the 1950s and 60s to the dry decades of the 1970s and 80s has been well documented. In recent years, a moderate recovery has emerged, with seasonal totals in the period 1994-2010 significantly higher than the average rainfall 1970-1993. These MDV rainfall fluctuations have expression in large-scale sea-surface temperature fluctuations in all ocean basins, placing the changes in drought frequency within broader ocean-atmosphere climate fluctuation. We have evaluated the changing character of low seasonal rainfall total event frequencies in the Sahel region 1950-2010, highlighting the role of changes in the mean, variance and distribution shape of seasonal rainfall totals as the climate has shifted through the three observed phases. We also consider the extent to which updating climate normals in real-time can damp the bias in expected event frequency, an important issue for the feasibility of index insurance as a drought management tool in the presence of a changing climate. On the interannual timescale, a key factor long discussed for agriculture is the character of rainfall onset. An extended dry spell often occurs early in the rainy season before the crop is fully established, and this often leads to crop

  6. Changes in Intense Precipitation Events in West Africa and the central U.S. under Global Warming

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Kerry H. [Univ. of Texas, Austin, TX (United States); Vizy, Edward [Univ. of Texas, Austin, TX (United States)

    2016-02-08

    The purpose of the proposed project is to improve our understanding of the physical processes and large-scale connectivity of changes in intense precipitation events (high rainfall rates) under global warming in West Africa and the central U.S., including relationships with low-frequency modes of variability. This is in response to the requested subject area #2 “simulation of climate extremes under a changing climate … to better quantify the frequency, duration, and intensity of extreme events under climate change and elucidate the role of low frequency climate variability in modulating extremes.” We will use a regional climate model and emphasize an understanding of the physical processes that lead to an intensification of rainfall. The project objectives are as follows: 1. Understand the processes responsible for simulated changes in warm-season rainfall intensity and frequency over West Africa and the Central U.S. associated with greenhouse gas-induced global warming 2. Understand the relationship between changes in warm-season rainfall intensity and frequency, which generally occur on regional space scales, and the larger-scale global warming signal by considering modifications of low-frequency modes of variability. 3. Relate changes simulated on regional space scales to global-scale theories of how and why atmospheric moisture levels and rainfall should change as climate warms.

  7. The monetary value of human milk in Francophone west Africa: a PROFILES analysis for nutrition policy communication.

    Science.gov (United States)

    Aguayo, Víctor M; Ross, Jay

    2002-06-01

    Using a simple and conservative methodology, we estimated the volume and monetary value of the human milk produced by lactating women in Francophone West Africa. In that region, children zero to 35.9 months old consume over 1.1 billion liters of human milk per year. However, suboptimal breastfeeding practices account for the loss of 175 million liters of human milk annually. If the human milk consumed by children zero to 35.9 months old were to be adequately replaced using commercial breastmilk substitutes, an annual expenditure of about 2 billion US dollars would be needed. At the household level, the annual replacement cost of human milk would amount to US$412 per infant. This is beyond the reach of most families in West Africa, where as many as 61% of families in some countries live on less than one US dollar per day. Appropriate policies to foster breastfeeding need to be developed and adequately implemented. Such policy action is more likely to occur if decision makers fully appreciate the monetary value of human milk.

  8. Evaluating climate change impacts and adaptation options for agriculture in West Africa: a multi-model comparison

    Science.gov (United States)

    Sultan, B.; Lobell, D. B.; Biasutti, M.; Guan, K.; Roudier, P.; Piani, C.

    2013-12-01

    Climate change is likely to stress food production in many parts of the developing world over the next few decades. In areas such as West Africa, where poor communities are highly dependent on the direct use of local natural resources, the effects of climate change on food security could be particularly devastating. Given these concerns, there is great interest in identifying and investing in technologies or practices that could help farmers adapt to climate variability and change. Recent studies found a robust agreement across the various climate models of the IPCC Coupled Models Inter-comparison Program ensemble on the seasonal distribution of Sahel rainfall changes (with a drying of the early season and positive rainfall anomaly at the end) in contrast with a large uncertainty for summertime rainfall totals. These changes will therefore certainly impact agriculture strategy (selection of new cultivars, later sowing) and output. This study estimates such impacts by using a series of climate scenarios as input for two crop models for multiple locations within West Africa. Simulations are run for the two major crops in the region - sorghum and millets. Building on the above simulations, we then simulate different scenarios of adaptation that could be used to cope with climate changes.

  9. The monetary value of human milk in Francophone west Africa: a PROFILES analysis for nutrition policy communication.

    Science.gov (United States)

    Aguayo, Víctor M; Ross, Jay

    2002-06-01

    Using a simple and conservative methodology, we estimated the volume and monetary value of the human milk produced by lactating women in Francophone West Africa. In that region, children zero to 35.9 months old consume over 1.1 billion liters of human milk per year. However, suboptimal breastfeeding practices account for the loss of 175 million liters of human milk annually. If the human milk consumed by children zero to 35.9 months old were to be adequately replaced using commercial breastmilk substitutes, an annual expenditure of about 2 billion US dollars would be needed. At the household level, the annual replacement cost of human milk would amount to US$412 per infant. This is beyond the reach of most families in West Africa, where as many as 61% of families in some countries live on less than one US dollar per day. Appropriate policies to foster breastfeeding need to be developed and adequately implemented. Such policy action is more likely to occur if decision makers fully appreciate the monetary value of human milk. PMID:12094665

  10. Solar drying of mangoes: preservation of an important source of vitamin A in French-speaking West Africa.

    Science.gov (United States)

    Rankins, Jenice; Sathe, Shridhar K; Spicer, Maria T

    2008-06-01

    Vitamin A deficiency, which is especially widespread among children younger than age 5 years, is a major barrier to reducing child mortality rates in French-speaking West Africa. A large amount of an indigenous plant source of provitamin A carotenoids are lost to postharvest waste. For example, the postharvest loss of mangoes in the region exceeds an annual total of 100,000 metric tons. In our study, 3.75 metric tons of fresh mangoes were dried using a solar dryer to a final moisture content of 10% to 12%, yielding a total of 360 kg dried mango. The product analysis revealed 4,000+/-500 microg beta carotene/100 g and 3,680+/-150 microg beta carotene/100 g after 2 and 6 months of storage, respectively. Thus, one greenhouse solar dryer is capable of reducing postharvest mango waste by 3.75 tons providing up to 1.15 million retinol activity equivalents of dietary vitamin A. The use of this technology that requires solar energy and manpower has the potential of increasing dietary vitamin A supply by up to 27,000-fold, compared to the currently available vitamin A in the region. Moreover, mango is a fruit that is well-liked by the population in this geographic area increasing the likelihood of its ready acceptance. Reducing postharvest loss of mangoes by using greenhouse model solar dryers is a promising strategy to help combat vitamin A deficiency in French-speaking West Africa. PMID:18502231

  11. High rates of parasite recrudescence following intermittent preventive treatment with sulphadoxine-pyrimethamine during pregnancy in Benin

    DEFF Research Database (Denmark)

    Moussiliou, Azizath; Sissinto-Savi De Tove, Yolande; Doritchamou, Justin;

    2013-01-01

    BACKGROUND: Despite widespread parasite resistance to sulphadoxine-pyrimethamine (SP) its use for intermittent preventative treatment during pregnancy remains the policy in Benin and throughout most of sub-Saharan Africa. METHODS: In a prospective study, 982 pregnant women were recruited in Benin...... the persistence of parasites and malaria consequences, were investigated. Recurrent parasites were genotyped to identify recrudescences from re-infections. RESULTS: The prevalence of pfdhfr/pfdhps quadruple mutants (triple pfdhfr + single pfdhps) was consistently above 80% while quintuple and sextuple mutants...

  12. Geostatistical model-based estimates of Schistosomiasis prevalence among individuals aged ≤ 20 years in West Africa.

    Directory of Open Access Journals (Sweden)

    Nadine Schur

    2011-06-01

    Full Text Available BACKGROUND: Schistosomiasis is a water-based disease that is believed to affect over 200 million people with an estimated 97% of the infections concentrated in Africa. However, these statistics are largely based on population re-adjusted data originally published by Utroska and colleagues more than 20 years ago. Hence, these estimates are outdated due to large-scale preventive chemotherapy programs, improved sanitation, water resources development and management, among other reasons. For planning, coordination, and evaluation of control activities, it is essential to possess reliable schistosomiasis prevalence maps. METHODOLOGY: We analyzed survey data compiled on a newly established open-access global neglected tropical diseases database (i to create smooth empirical prevalence maps for Schistosoma mansoni and S. haematobium for individuals aged ≤ 20 years in West Africa, including Cameroon, and (ii to derive country-specific prevalence estimates. We used Bayesian geostatistical models based on environmental predictors to take into account potential clustering due to common spatially structured exposures. Prediction at unobserved locations was facilitated by joint kriging. PRINCIPAL FINDINGS: Our models revealed that 50.8 million individuals aged ≤ 20 years in West Africa are infected with either S. mansoni, or S. haematobium, or both species concurrently. The country prevalence estimates ranged between 0.5% (The Gambia and 37.1% (Liberia for S. mansoni, and between 17.6% (The Gambia and 51.6% (Sierra Leone for S. haematobium. We observed that the combined prevalence for both schistosome species is two-fold lower in Gambia than previously reported, while we found an almost two-fold higher estimate for Liberia (58.3% than reported before (30.0%. Our predictions are likely to overestimate overall country prevalence, since modeling was based on children and adolescents up to the age of 20 years who are at highest risk of infection. CONCLUSION

  13. The perception of radioactive waste among the people of Africa

    International Nuclear Information System (INIS)

    Full text: West Africa is one of the Africa's most populated regions, with a total population of approximately 200 million people. The West African sub-region comprises of sixteen different countries, which are as follows: Nigeria, Benin, Togo, Ghana, Code Ivore, Guinea, Guinea Bissau, Liberia, Sierra-Leone, Gambia, Senegal, Mauritania, Western Sahara, Mali, Burkina Faso and Niger Republique. Apart from Nigeria, Senegal and Ghana all the other remaining' countries are extremely poor and unviable. As a result of this the sub-region has been experiencing a lot of civil unrest, countries like Liberia, Sierra Leon and Code Ivore have been experiencing civil wars since the early 1990s. In addition to the already existing problems of trafficking in drugs, arms, humans and weaponry trade within the sub-region. Today the sub-region is experiencing the coming of a new evil deal called 'Trade in radio active waste'; which involves the transporting Of radioactive wastes from the developed countries to it's waste bin in West Africa, where it is unsafely buried after collecting millions of dollars from It's original owners. Recent statistics have revealed that most of the people involved in the evil businesses of trafficking in drugs, human, arms and trading in weaponry, are diverting in to the so called evil business of 'Trade in Radioactive waste' because this new illegal trade financially exceeds the rest of the above listed evil businesses

  14. Characterization of African Bush Mango trees with emphasis on the differences between sweet and bitter trees in the Dahomey Gap (West Africa)

    OpenAIRE

    Vihotogbe, R.

    2012-01-01

     African bush mango trees (ABMTs) are economically the most important species within the family of Irvingiaceae. They are priority trees producing non-timber forest products (NTFPs) and widely distributed in the humid lowland forests of West and Central Africa. To boost their production and develop them towards a major crop for rural communities in Africa, a domestication program was initiated in the 2000s which is being coordinated by the World Agroforestry Centre. ABMTs belong to two t...

  15. Water availability and demand in West Africa in the 21st century: impacts of climate change and population growth

    Science.gov (United States)

    Wisser, Dominik; Oyerinde, Ganiyu; Ibrahim, Moussa; Ibrahim, Boubacar

    2014-05-01

    The countries in West Africa are highly dependent on rainfed agriculture. Changes in the magnitude and timing of precipitation will affect the agricultural output and the economies as a whole. Irrigation is increasingly being considered an important adaptation option to help improve food security of the population that is expected to double in less than 50 years. West Africa is one of the regions where general circulation models (GCM) show the highest disagreements in the direction of future trends of precipitation, making assessments of water availability and the potential for irrigation a difficult task. We use output from a set of dynamically downscaled climate data sets from regional climate modes (RCM) from the CORDEX CMIP5 collection to drive WBMplus, a macroscale hydrological model and simultaneously calculate water demand (livestock, domestic, and irrigation) and availability for a set of land use, and socio economic scenarios around the 2050's for river basins in the ten countries participating in the West African Science Service Center on Climate Change and Adapted Land Use (WASCAL) project. Contrary to earlier results from GCMs, the set of RCMs suggest a consistent increase (~5-10%) in annual precipitation for a majority of the land area in West Africa that translates to slight increases in river flow under natural conditions for most river basins and a opportunities for increasing irrigation during the dry season. However, water demand is projected to more than double for livestock and domestic needs as a result of population growth. Demand for irrigation will rise sharply if irrigation is expanded from the current area (representing less than 3% of all croplands in the region), closer to its potential which is multiple times higher than the existing area. The pressures on water resources in the region will therefore be dominated by pressures arising from increased demand rather than changes in the availability of water and can potentially lead to

  16. A systematic assessment of the current capacity to act in nutrition in West Africa: cross-country similarities and differences

    Directory of Open Access Journals (Sweden)

    Roger Sodjinou

    2014-07-01

    Full Text Available Background: Although it is widely accepted that lack of capacity is one of the barriers to scaling up nutrition in West Africa, there is a paucity of information about what capacities exist and the capacities that need to be developed to accelerate progress toward improved nutrition outcomes in the region. Objective: To systematically assess the current capacity to act in nutrition in the West Africa region and explore cross-country similarities and differences. Design: Data were collected from 13 West African countries through interviews with government officials, key development partners, tertiary-level training institutions, and health professional schools. The assessment was based on a conceptual framework of four interdependent levels (tools; skills; staff and infrastructure; and structures, systems and roles. In each of the surveyed countries, we assessed capacity assets and gaps at individual, organizational, and systemic levels. Results: Important similarities and differences in capacity assets and gaps emerged across all the surveyed countries. There was strong momentum to improve nutrition in nearly all the surveyed countries. Most of the countries had a set of policies on nutrition in place and had set up multisectoral, multi-stakeholder platforms to coordinate nutrition activities, although much remained to be done to improve the effectiveness of these platforms. Many initiatives aimed to reduce undernutrition were ongoing in the region, but there did not seem to be clear coordination between them. Insufficient financial resources to implement nutrition activities were a major problem in all countries. The bulk of financial allocations for nutrition was provided by development partners, even though some countries, such as Niger, Nigeria, and Senegal, had a national budget line for nutrition. Sporadic stock-outs of nutrition supplies were reported in most of the countries as a result of a weak logistic and supply chain system. They

  17. Aid and trade for livestock development and food security in West Africa

    NARCIS (Netherlands)

    Lee, van der J.; Schiere, J.B.; Bosma, R.H.; Olde, de E.; Bol, S.; Cornelissen, J.M.R.

    2014-01-01

    Veehouderij is in West Afrika van oudsher erg belangrijk. Het kent vele vormen en dient veel doelen, die vooral verschuiven van noord naar zuid. Deze analyse van de West Afrikaanse veehouderij is een quickscan geschreven door Wageningen UR Livestock Research en La Ventana consulting. Zij dient met n

  18. Identification and Characterization of CRF02_AG, CRF06_cpx, and CRF09_cpx Recombinant Subtypes in Mali, West Africa

    Science.gov (United States)

    Koita, Ousmane; Dabitao, Djeneba; Dao, Sounkalo; Ibrah, Mahamadou; Sogoba, Dramane; Dewar, Robin L.; Berg, Steve C.; Jiang, Min-Kang; Parta, Mark; Washington, Janice A.; Polis, Michael A.; Lane, H. Clifford; Tounkara, Anatole

    2009-01-01

    Abstract Multiple HIV-1 subtypes and circulating recombinant forms (CRFs) are known to cocirculate in Africa. In West Africa, the high prevalence of CRF02_AG, and cocirculation of subtype A, CRF01_AE, CRF06_cpx, and other complex intersubtype recombinants has been well documented. Mali, situated in the heart of West Africa, is likely to be affected by the spread of recombinant subtypes. However, the dynamics of the spread of HIV-1 recombinant subtypes as well as nonrecombinant HIV-1 group M subtypes in this area have not been systematically assessed. Herein, we undertook genetic analyses on full-length env sequences derived from HIV-1-infected individuals living in the capital city of Mali, Bamako. Of 23 samples we examined, 16 were classified as CRF02_AG and three had a subsubtype A3. Among the remaining HIV-1 strains, CRF06_cpx and CRF09_cpx were each found in two patients. Comparison of phylogenies for six matched pol and full-length env sequences revealed that two strains had discordant subtype/CRF designations between the pol and env regions: one had A3polCRF02_AGenv and the other had CRF02_AGpolA3env. Taken together, our study demonstrated the high prevalence of CRF02_AG and complexity of circulating HIV-1 strains in Mali. It also provided evidence of ongoing virus evolution of CRF02_AG, as illustrated by the emergence of more complex CRF02_AG/A3 intersubtype recombinants in this area. PMID:19182920

  19. The importance of baobab (Adansonia digitata L.) in rural West African subsistence--suggestion of a cautionary approach to international market export of baobab fruits.

    Science.gov (United States)

    Buchmann, Christine; Prehsler, Sarah; Hartl, Anna; Vogl, Christian R

    2010-01-01

    The European Commission recently authorized the import of baobab (Adansonia digitata L.) fruit pulp as a novel food. In rural West Africa the multipurpose baobab is used extensively for subsistence. Three hundred traditional uses of the baobab were documented in Benin, Mali, and Senegal across 11 ethnic groups and 4 agroecological zones. Baobab fruits and leaves are consumed throughout the year. The export of baobab fruits could negatively influence livelihoods, including reduced nutritional intake, change of power relations, and access rights. Capacity building and certification could encourage a sustainable and ethical trade of baobab fruits without neglecting baobab use in subsistence.

  20. An analysis of knowledge and opinions on xenophobia among North West University students, Mafikeng Campus, South Africa (2008-2010) / Onyebukwa Ogochukwu Laura.

    OpenAIRE

    Laura, Onyebukwa Ogochukwu

    2011-01-01

    The main objective of this study was to analyze the knowledge and opinions on Xenophobia among Students in North West University, Mafikeng Campus, North-West Province, South Africa. The hypotheses tested by the research were that negative opinions about foreigners lead to inclination to xenophobia; positive opinions about foreigners lead to non-inclination toward xenophobia and that economic and sociological factors influence negative opinions about foreigners. The results of the study ...

  1. Retinal vein occlusion in Benin City, Nigeria

    OpenAIRE

    Uhumwangho, Odarosa M.; Darlingtess Oronsaye

    2016-01-01

    Background: Retinal vein occlusion (RVO) is the most common occlusive retinal vascular disorder and results in varying degrees of visual loss. Aim: To determine the pattern of presentation, risk factors, and treatment outcomes in a group of patients with RVO seen in a tertiary hospital in Nigeria. Materials and Methods: Medical records of patients who presented to the University of Benin Teaching Hospital, Benin City, Nigeria in whom a diagnosis of RVO was made over a 5 years period were revi...

  2. The UNEP Shelf Programme: Highlighting efforts in West Africa and the Pacific Islands

    Science.gov (United States)

    Baker, E.; Beaudoin, Y. C.; Brekke, H.; Fabres, J.; Halvorsen, O.; Harris, P. T.; Lonne, O.; Nilsen, R.; Sorensen, M.; Thygesen, K.

    2013-12-01

    The UNEP Shelf Programme, coordinated by GRID-Arendal (a center collaborating with UNEP) was established in 2003 in response to Article 76 of the UN Convention on the Law of the Sea (UNCLOS) and UN General Assembly resolution 57/141. The Programme provides scientific and technical support to developing countries to assist in making timely submissions under the Convention to establish the outer limits of their continental shelf. The deadline for most states was midnight on 12 May 2009. All states that were expected to submit, managed to meet the deadline, and almost all developing states received support from the UNEP Shelf Programme. The support ranged from comprehensive capacity building and tailor-made training, to access to data from GRID-Arendal's One Stop Data Shop (OSDS). Two case studies will be presented and discussed: In the period from 8 December 2011 to 20 June 2012, the ship 'Sea Surveyor' of Gardline Hydro carried out a regional marine acquisition program off West Africa. The acquisition program was part of a joint project between seven African states (Mauretania, Senegal, the Gambia, Cape Verde, Guinea Bissau, Guinea and Sierra Leone) in cooperation with the Government of Norway. The data were acquired for the purpose of delineating and documenting the outer limits of the continental shelf of the seven states in accordance with article 76 of UNCLOS. Multibeam bathymetry (40 000 km) was acquired for the identification of the base of slope (BOS) and for the detailed foot of slope (FOS) analyses. Single channel reflection seismic (36 000 km) and sub bottom profiler data (40 000 km) were acquired for the interpretation of the general geology (including basement characteristics and sediment thickness) and recent sedimentary processes, respectively, as supportive evidence in the establishment of the BOS. In two areas, multi channel reflection seismic (4 000 km) data were acquired for the purpose of detailed sediment thickness analyses. Wide-angle reflection

  3. Full-Genome Sequence of a Neuroinvasive West Nile Virus Lineage 2 Strain from a Fatal Horse Infection in South Africa.

    Science.gov (United States)

    Mentoor, Juliet L D; Lubisi, Alison B; Gerdes, Truuska; Human, Stacey; Williams, June H; Venter, Marietjie

    2016-01-01

    We report here the complete genome sequence of a lineage 2 West Nile virus (WNV) strain that resulted in fatal neurological disease in a horse in South Africa. Several recent reports exist of neurological disease associated with lineage 2 WNV in humans and horses in South Africa and Europe; however, there are a lack of sequencing data from recent fatal cases in Southern Africa, where these strains likely originate. A better understanding of the genetic composition of highly neuroinvasive lineage 2 strains may facilitate the identification of putative genetic factors associated with increased virulence. PMID:27469963

  4. Full-Genome Sequence of a Neuroinvasive West Nile Virus Lineage 2 Strain from a Fatal Horse Infection in South Africa

    Science.gov (United States)

    Mentoor, Juliet L. D.; Lubisi, Alison B.; Gerdes, Truuska; Human, Stacey; Williams, June H.

    2016-01-01

    We report here the complete genome sequence of a lineage 2 West Nile virus (WNV) strain that resulted in fatal neurological disease in a horse in South Africa. Several recent reports exist of neurological disease associated with lineage 2 WNV in humans and horses in South Africa and Europe; however, there are a lack of sequencing data from recent fatal cases in Southern Africa, where these strains likely originate. A better understanding of the genetic composition of highly neuroinvasive lineage 2 strains may facilitate the identification of putative genetic factors associated with increased virulence. PMID:27469963

  5. Nutrients, technological properties and genetic relationships among twenty cowpea landraces cultivated in West Africa

    NARCIS (Netherlands)

    Madode, Y.E.E.; Linnemann, A.R.; Nout, M.J.R.; Vosman, B.J.; Hounhouigan, D.J.; Boekel, van T.

    2012-01-01

    The genetic relationships among twenty phenotypically different cowpea landraces were unravelled regarding their suitability for preparing West African dishes. Amplified fragment length polymorphism classified unpigmented landraces (UPs) as highly similar (65%, one cluster), contrary to pigmented la

  6. Masked millennial-scale climate variations in South West Africa during the last glaciation

    Directory of Open Access Journals (Sweden)

    I. Hessler

    2012-04-01

    Full Text Available To address the connection between tropical African vegetation development and high-latitude climate change we present a high-resolution pollen record from ODP Site 1078 (off Angola covering the period 50–10 ka BP. Although several tropical African vegetation and climate reconstructions indicate an impact of Heinrich Stadials (HSs in Southern Hemisphere Africa, our vegetation record shows no response. Model simulations conducted with an Earth System Model of Intermediate Complexity including a dynamical vegetation component provide one possible explanation. Because both precipitation and evaporation increased during HSs and their effects nearly cancelled each other, there was a negligible change in moisture supply. Consequently, the resulting climatic response to HSs might have been too weak to noticeably affect the vegetation composition in the study area. Our results also show that the response to HSs in southern tropical Africa neither equals nor mirrors the response to abrupt climate change in northern Africa.

  7. The consequences of appointment policies for court legitimacy in Benin: A network analysis approach

    OpenAIRE

    Stroh, Alexander

    2016-01-01

    The paper seeks to explain how courts in new and vulnerable democracies acquire legitimacy and thus become credible actors able to facilitate or even foster the consolidation of democracy. It analyses the case of the Constitutional Court of Benin (CCB), demonstrating that governmental appointment policies have had an important impact on the court's legitimacy. This West African country is considered to have been continuously democratic since 1991, and the court was established by consensus du...

  8. Determinants of soybean [Glycine max (L. Merrill] production system in Benin

    Directory of Open Access Journals (Sweden)

    Charlotte Carmelle Zoundji

    2015-10-01

    Full Text Available Present study was conducted to analyze the soybean production system in Benin. Data were collected from 324 soybean producers selected from the three major soybean-producing agro-ecological areas i.e. agro-ecological zone 3 (southern Borgou, agro-ecological zone 4 (West Atacora and agro-ecological zone 5 (Cotton zone of the Centre of Benin. A participatory research approach with group discussions followed by individual interviews was carried out for extracting the information from respondents. Information mainly referred to the socio-demographic characteristics of soybean producers, production practices, extent of yields and constraints. Descriptive statistics were then used to analyze the data. Ordered Probit regression was further carried out to assess the determinants of soybean yield levels in Benin. Results of this study revealed that soybean producers of the three agro ecological zones have most of the common demographic characteristics. They equally revealed that farmers do not follow correct soybean cropping practices. Improved seeds, plant density, fertilizers, fallow, and sex of farmers have significantly (P<0.05, P<0.01, P<0.001 influenced the yields of soybean in Benin. Within the context of sustainable agricultural production practices, it is recommended to develop appropriate technologies for soybean cultivation. The extension services should focus more on the appropriate combination of input resources which are found to contribute more to the soybean production

  9. First record of a white rough-toothed dolphin (Steno bredanensis) off West Africa including notes on rough-toothed dolphin surface behaviour

    NARCIS (Netherlands)

    Boer, de M.N.

    2010-01-01

    In June 2009, a white rough-toothed dolphin (Steno bredanensis) calf was photographed in a group of at least 50 dolphins in the southern Gulf of Guinea, 95 nauticol miles off the Gabon coast (01°45'S 007°29'E), West Africa. Reports of unusually pigmented cetaceans are infrequent and this record repr

  10. Exploring the diversity of urban and peri-urban agricultural systems in Sudano-Sahelian West Africa: An attempt towards a regional typology

    NARCIS (Netherlands)

    Dossa, L.C.; Abdulkadir, A.; Amadou, H.; Sangare, S.; Schlecht, E.

    2011-01-01

    Developing appropriate and innovative technologies and policies to respond to the challenges that urban and peri-urban agriculture (UPA) faces in West Africa requires a better understanding of the existing production systems. Although there is an increasing recognition of the importance of UPA in th

  11. Development of reference transcriptomes for the major insect pests of cowpea: a toolbox for insect pest management approaches in West Africa

    Science.gov (United States)

    Cowpea crops are widely cultivated and a major nutritional source of protein for indigenous human populations in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include Anoplocnemis curvipes, Aphis craccivora, Cl...

  12. Black-tailed Godwit Demographic Project - Why should Black-tailed Godwits still winter in West-Africa if Southern Iberia is just as good?

    NARCIS (Netherlands)

    Hooijmeijer, Joslyn; Valkema, Haije; Loos, Bob; Piersma, Theun

    2014-01-01

    In November 2014 the University of Groningen, in cooperation with Global Flyway Network and financially supported by Birdlife Netherlands, embarked upon a 19 days expedition to the wintering grounds in West-Africa. We aim to set up a demographic research project in this area. Most important goal of

  13. Characterization of African Bush Mango trees with emphasis on the differences between sweet and bitter trees in the Dahomey Gap (West Africa)

    NARCIS (Netherlands)

    Vihotogbe, R.

    2012-01-01

     African bush mango trees (ABMTs) are economically the most important species within the family of Irvingiaceae. They are priority trees producing non-timber forest products (NTFPs) and widely distributed in the humid lowland forests of West and Central Africa. To boost their production and dev

  14. An introduction to the SCOUT-AMMA stratospheric aircraft, balloons and sondes campaign inWest Africa, August 2006: rationale and roadmap

    NARCIS (Netherlands)

    Cairo, F.; Kerstel, E.R.T.; Roeckmann, T.

    2010-01-01

    A multi-platform field measurement campaign involving aircraft and balloons took place overWest Africa between 26 July and 25 August 2006, in the frame of the concomitant AMMA Special Observing Period and SCOUT-O3 African tropical activities. Specifically aiming at sampling the upper troposphere and

  15. An introduction to the SCOUT-AMMA stratospheric aircraft, balloons and sondes campaign in West Africa, August 2006 : rationale and roadmap

    NARCIS (Netherlands)

    Cairo, F.; Pommereau, J. P.; Law, K. S.; Schlager, H.; Garnier, A.; Fierli, F.; Ern, M.; Streibel, M.; Arabas, S.; Borrmann, S.; Berthelier, J. J.; Blom, C.; Christensen, T.; D'Amato, F.; Di Donfrancesco, G.; Deshler, T.; Diedhiou, A.; Durry, G.; Engelsen, O.; Goutail, F.; Harris, N. R. P.; Kerstel, E. R. T.; Khaykin, S.; Konopka, P.; Kylling, A.; Larsen, N.; Lebel, T.; Liu, X.; MacKenzie, A. R.; Nielsen, J.; Oulanowski, A.; Parker, D. J.; Pelon, J.; Polcher, J.; Pyle, J. A.; Ravegnani, F.; Riviere, E. D.; Robinson, A. D.; Rockmann, T.; Schiller, C.; Simoes, F.; Stefanutti, L.; Stroh, F.; Some, L.; Siegmund, P.; Sitnikov, N.; Vernier, J. P.; Volk, C. M.; Voigt, C.; von Hobe, M.; Viciani, S.; Yushkov, V.

    2010-01-01

    A multi-platform field measurement campaign involving aircraft and balloons took place over West Africa between 26 July and 25 August 2006, in the frame of the concomitant AMMA Special Observing Period and SCOUT-O-3 African tropical activities. Specifically aiming at sampling the upper troposphere a

  16. Region-wide assessment of the capacity for human nutrition training in West Africa: current situation,challenges, and way forward

    NARCIS (Netherlands)

    Sodjinou, R.; Fanou, N.; Deart, L.; Pepping, F.

    2014-01-01

    Background: There is a dearth of information on existing nutrition training programs in West Africa. A preliminary step in the process of developing a comprehensive framework to strengthen human capacity for nutrition is to conduct an inventory of existing training programs. Objective: This study wa

  17. Rainfall retrievals over West Africa using SEVIRI: evaluation with TRMM-PR and monitoring of the daylight time monsoon progression

    Directory of Open Access Journals (Sweden)

    E. L. A. Wolters

    2010-08-01

    Full Text Available This paper describes the application of the KNMI cloud physical properties – precipitation properties (CPP-PP algorithm over West Africa. The algorithm combines condensed water path (CWP, cloud phase (CPH, cloud particle effective radius (re, and cloud-top temperature (CTT information, retrieved from visible, near-infrared and infrared observations of the Spinning Enhanced Visible and Infrared Imager (SEVIRI onboard Meteosat-9 to estimate precipitation occurrence and intensity. It is investigated whether the CPP-PP algorithm is capable of retrieving rain occurrence and intensity over West Africa with a sufficient accuracy, using tropical monsoon measurement mission precipitation radar (TRMM-PR and a small number of rain gauge observations as reference. As a second goal, it is assessed whether SEVIRI is capable of monitoring both the seasonal and synoptical evolution of the West African monsoon (WAM. It is shown that the SEVIRI-detected rainfall area agrees well with TRMM-PR, having a correlation coefficient of 0.86, with the areal extent of rainfall by SEVIRI being ~10% larger than TRMM-PR. The mean retrieved rain rate from CPP-PP is about 8% higher than from TRMM-PR. The frequency distributions of rain rate reveal that the median rain rates of CPP-PP and TRMM-PR are similar. However, rain rates >7 mm h−1 are retrieved more frequently by SEVIRI than by TRMM-PR, which is partly explained by known biases in TRMM-PR. Finally, it is illustrated that both the seasonal and synoptical time scale of the WAM can be well detected from SEVIRI daytime observations. It was found that the daytime westward MCS travel speed fluctuates between 50 and 60 km h−1. Furthermore, the ratio of MCS precipitation to the total precipitation was estimated to be about 27%. Our results indicate that rainfall retrievals from SEVIRI can be used to monitor the West African monsoon.

  18. Radiative Effects and Feedbacks of Saharan Dust and Biomass Burning Aerosol over West Africa and the Northern Tropical Atlantic

    Science.gov (United States)

    Heinold, Bernd; Tegen, Ina; Bauer, Stefan; Wendisch, Manfred

    2010-05-01

    Soil dust aerosol from the world's arid and semi-arid regions and land fire smoke represent major components of the atmospheric aerosol load. They influence the climate system by changing the atmospheric radiation balance through direct and indirect effects and play an important role in the biogeochemical and hydrological cycle. However, in particular the magnitude and sign of the radiative effects are highly uncertain due to still existing uncertainties in their optical properties and the variability and complexity of the spatio-temporal distribution. The dust and biomass burning aerosol from Africa is of particular interest since the continent harbours the largest and most active sources of both aerosol types. The Saharan and Sahel regions contribute at least 50% to the global dust emissions and a considerable amount of smoke originates from active biomass burning areas in west and central Africa. Within continuous aerosol outbreaks, the Saharan dust and land fire smoke are transported towards the West African Monsoon region and across the tropical Atlantic Ocean. In boreal winter, when the most land fires are active, the Saharan dust layer merges with the West African smoke plumes resulting in a complex aerosol layering. Here, the results of a regional model study on direct radiative forcing and dynamic atmospheric response due to dust and biomass burning aerosol will be presented. Particular focus will be on radiative impacts on regional circulation patterns and implications for the aerosol transport. For simulations of the complex spatial distribution of the West African aerosol and estimates of direct radiative effects and feedbacks, the regional model system COSMO-MUSCAT is used. The model allows online interaction of the computed dust and biomass burning aerosol load with the solar and thermal radiation and with the model dynamics. The simulations are performed for the second field campaign of the SAharan Mineral dUst experiMent (SAMUM) that was conducted

  19. Kyllinga cataphyllata (Cyperaceae), a new species from the highlands of West and Central Africa

    NARCIS (Netherlands)

    Huygh, W.; Schouppe, D.; Larridon, I.; Simpson, D.A.; Goetghebeur, P.

    2010-01-01

    Kyllinga cataphyllata, a new species of Cyperaceae from the highlands of Western and Central Africa, is described and illustrated. This new species is easy recognized by the ascending rhizome densely covered by large cataphylls. The head-like inflorescence consisting of a single spike with spikelets

  20. Long-term effects of conservation soil management in Saria, Burkina Faso, West Africa

    NARCIS (Netherlands)

    Zacharie, Z.

    2011-01-01

    The negative degradation spiral that currently leads to deteriorating soil properties in African drylands is a serious problem that limits food production and threatensthe livelihoods of the people. Nutrient depletion and water and wind erosion are the main factors in soil degradation in Africa. Thi

  1. Integrated water pollution assessment of the Ebrié Lagoon, Ivory Coast, West Africa

    NARCIS (Netherlands)

    Scheren, P.A.G.M.; Kroeze, C.; Jansen, F.J.J.G.; Hordijk, L.; Ptasinski, K.J.

    2004-01-01

    An environmental pollution assessment of the Ebrie lagoon, the largest coastal ecosystem in Western Africa, was executed by applying the Driving force-Pressure-State-Impacts-Response (DPSIR) framework. The domestic and industrial activities in Abidjan and agricultural activities in the wider catchme

  2. Strengthening malaria prevention and control: integrating West African militaries' malaria control efforts. The inaugural meeting of the West African Malaria Task Force, April 24-26, 2013, Accra, Ghana.

    Science.gov (United States)

    McCollum, Jeffrey T; Hanna, Refaat; Halbach, Alaina C; Cummings, James F

    2015-01-01

    From April 24 to 26, 2013, the Armed Forces Health Surveillance Center and the U.S. Africa Command cosponsored the inaugural meeting of the West Africa Malaria Task Force in Accra, Ghana. The meeting's purpose was to identify common challenges, explore regional and transcontinental collaborations, and to share knowledge about best practices in the fight against malaria in West Africa. Military representatives from Benin, Burkina Faso, Ghana, Liberia, Niger, Nigeria, Senegal, and Togo participated in the Task Force; various U.S. Government agencies were also represented, including the Department of Defense, the Centers for Disease Control and Prevention, and the Agency for International Development. African nation participants presented brief overviews of their military's malaria prevention and control measures, surveillance programs, diagnostic capabilities, and treatment regimens emphasizing gaps within existing programs. Representatives from U.S. agencies discussed activities and capabilities relevant for the region, challenges and lessons learned regarding malaria, and highlighted opportunities for enhanced partnerships to counter malaria in West Africa. This article summarizes the major conclusions of the Task Force meeting, identifies relevant focus areas for future Task Force activities, and outlines opportunities for further inclusion of West African militaries to improve regional malaria surveillance and control efforts.

  3. Ectoparasites of dogs belonging to people in resource-poor communities in North West Province, South Africa

    Directory of Open Access Journals (Sweden)

    N.R. Bryson

    2000-07-01

    Full Text Available A total of 344 dogs belonging to people in resource-poor communities in North West Province, South Africa, was examined for ectoparasites, and all visible arthropods were collected from the left side of each dog. By doubling these numbers it was estimated that the dogs harboured 14 724 ixodid ticks, belonging to 6 species, 1028 fleas, belonging to 2 species, and 26 lice. Haemaphysalis leachi accounted for 420 and Rhipicephalus sanguineus for 14 226 of the ticks. Pure infestations of H. leachi were present on 14 dogs and of R. sanguineus on 172 dogs. Small numbers of Amblyomma hebraeum, R. appendiculatus, R. evertsi evertsi and R. simus were also collected. The predominance of R. sanguineus accounts for the high prevalence of canine ehrlichiosis (Ehrlichia canis within the survey region, compared to canine babesiosis (Babesia canis, which is transmitted by H. leachi, and is a much rarer disease.

  4. Policies to improve the local impact from hydrocarbon extraction: Observations on West Africa and possible lessons for Central Asia

    International Nuclear Information System (INIS)

    The paper offers specific inputs to the debate on local content promotion in the oil industries of West Africa and Central Asia. To this end, we document the international experience with local content promotion to derive best practices in the field. We then use a case study approach to devise a simple analytical framework for rationalizing the selection of viable sectors for local content promotion, in an attempt to make operational one of the best practice principles (efficiency) developed before. By proposing specific rules regarding the acceptability of a project, the analysis seeks to add rigor and address distortions on localization outcomes from rent-seeking. The emphasis is not on supporting efforts to 'pick winners' and subsidize them through a range of by and large discredited instruments. Rather, the paper focuses on the specific public inputs the government would have to provide to support an otherwise market-driven process

  5. Review on the Molecular Tools for the Understanding of the Epidemiology of Animal Trypanosomosis in West Africa

    Directory of Open Access Journals (Sweden)

    Duvallet G

    1999-01-01

    Full Text Available The epidemiology of animal trypanosomosis around Bobo-Dioulasso (Burkina Faso, West Africa benefited a lot in the last years from the progress of molecular tools. The two most used molecular techniques were the polymerase chain reaction for the diagnosis of the disease in cattle and the characterization of the trypanosomes in the host and the vector on one hand, and the microsatellite DNA polymorphism in tsetse flies to study the intraspecific genetic variability of the vector on the other hand. The results obtained in the Sideradougou area during a recent two year survey with these techniques, associated with many other georeferenced informations concerning vector and cattle distribution, natural environment, landuse, ground occupation, livestock management, were combined in a Geographical Information System. This new approach of a complex pathogenic system led to a better evaluation of the risk of trypanosome transmission.

  6. Report of the workshop on strategic planning of area-wide tsetse and trypanosomiasis control in West Africa

    International Nuclear Information System (INIS)

    science-based standards for designing viable, sustainable T and T interventions in West Africa. The workshop was attended by staff of FAO, IAEA, CIRDES, ITC, ILRI specialists in the field of T and T and related development, field workers and those involved in the administration of PATTEC

  7. Heterogeneity in District-Level Transmission of Ebola Virus Disease during the 2013-2015 Epidemic in West Africa

    Science.gov (United States)

    Gsteiger, Sandro; Low, Nicola; Hansen, Christian H.; Althaus, Christian L.

    2016-01-01

    The Ebola virus disease (EVD) epidemic in West Africa in 2013–2015 spread heterogeneously across the three hardest-hit countries Guinea, Liberia and Sierra Leone and the estimation of national transmission of EVD provides little information about local dynamics. To investigate district-level transmissibility of EVD, we applied a statistical modelling approach to estimate the basic reproduction number (R0) for each affected district and each country using weekly incident case numbers. We estimated growth rates during the early exponential phase of the outbreak using exponential regression of the case counts on the first eight weeks since onset. To take into account the heterogeneity between and within countries, we fitted a mixed effects model and calculated R0 based on the predicted individual growth rates and the reported serial interval distribution. At district level, R0 ranged from 0.36 (Dubréka) to 1.72 (Beyla) in Guinea, from 0.53 (Maryland) to 3.37 (Margibi) in Liberia and from 1.14 (Koinadugu) to 2.73 (Western Rural) in Sierra Leone. At national level, we estimated an R0 of 0.97 (95% CI 0.77–1.18) for Guinea, 1.26 (95% CI 0.98–1.55) for Liberia and 1.66 (95% CI 1.32–2.00) for Sierra Leone. Socio-demographic variables related to urbanisation such as high population density and high wealth index were found positively associated with R0 suggesting that the consequences of fast urban growth in West Africa may have contributed to the increased spread of EVD. PMID:27434164

  8. The spatial genetic differentiation of the legume pod borer, Maruca vitrata F. (Lepidoptera: Crambidae) populations in West Africa

    KAUST Repository

    Agunbiade, Tolulope A.

    2012-04-17

    The legume pod borer, Maruca vitrata, is an endemic insect pest that causes significant yield loss to the cowpea crop in West Africa. The application of population genetic tools is important in the management of insect pests but such data on M. vitrata is lacking. We applied a set of six microsatellite markers to assess the population structure of M. vitrata collected at five sites from Burkina Faso, Niger and Nigeria. Observed polymorphisms ranged from one (marker 3393) to eight (marker 32008) alleles per locus. Observed and expected heterozygosities ranged from 0.0 to 0.8 and 0.0 to 0.6, respectively. Three of the loci in samples from Nigeria and Burkina Faso deviated significantly from Hardy-Weinberg Equilibrium (HWE), whereas no loci deviated significantly in samples from Niger. Analysis of molecular variance (AMOVA) indicated that 67.3% level of the genetic variation was within individuals compared to 17.3% among populations. A global estimate of F ST=0.1 (ENA corrected F ST=0.1) was significant (Pa=0.05) and corroborated by pairwise F ST values that were significant among all possible comparisons. A significant correlation was predicted between genetic divergence and geographic distance between subpopulations (R2=0.6, P=0.04), and cluster analysis by the program STRUCTURE predicted that co-ancestry of genotypes were indicative of three distinct populations. The spatial genetic variance among M. vitrata in West Africa may be due to limited gene flow, south-north seasonal movement pattern or other reproductive barriers. This information is important for the cultural, chemical and biological control strategies for managing M. vitrata. Copyright © 2012 Cambridge University Press.

  9. Heterogeneity in District-Level Transmission of Ebola Virus Disease during the 2013-2015 Epidemic in West Africa.

    Science.gov (United States)

    Krauer, Fabienne; Gsteiger, Sandro; Low, Nicola; Hansen, Christian H; Althaus, Christian L

    2016-07-01

    The Ebola virus disease (EVD) epidemic in West Africa in 2013-2015 spread heterogeneously across the three hardest-hit countries Guinea, Liberia and Sierra Leone and the estimation of national transmission of EVD provides little information about local dynamics. To investigate district-level transmissibility of EVD, we applied a statistical modelling approach to estimate the basic reproduction number (R0) for each affected district and each country using weekly incident case numbers. We estimated growth rates during the early exponential phase of the outbreak using exponential regression of the case counts on the first eight weeks since onset. To take into account the heterogeneity between and within countries, we fitted a mixed effects model and calculated R0 based on the predicted individual growth rates and the reported serial interval distribution. At district level, R0 ranged from 0.36 (Dubréka) to 1.72 (Beyla) in Guinea, from 0.53 (Maryland) to 3.37 (Margibi) in Liberia and from 1.14 (Koinadugu) to 2.73 (Western Rural) in Sierra Leone. At national level, we estimated an R0 of 0.97 (95% CI 0.77-1.18) for Guinea, 1.26 (95% CI 0.98-1.55) for Liberia and 1.66 (95% CI 1.32-2.00) for Sierra Leone. Socio-demographic variables related to urbanisation such as high population density and high wealth index were found positively associated with R0 suggesting that the consequences of fast urban growth in West Africa may have contributed to the increased spread of EVD. PMID:27434164

  10. Projecting Future Land Use Changes in West Africa Driven by Climate and Socioeconomic Factors: Uncertainties and Implications for Adaptation

    Science.gov (United States)

    Wang, G.; Ahmed, K. F.; You, L.

    2015-12-01

    Land use changes constitute an important regional climate change forcing in West Africa, a region of strong land-atmosphere coupling. At the same time, climate change can be an important driver for land use, although its importance relative to the impact of socio-economic factors may vary significant from region to region. This study compares the contributions of climate change and socioeconomic development to potential future changes of agricultural land use in West Africa and examines various sources of uncertainty using a land use projection model (LandPro) that accounts for the impact of socioeconomic drivers on the demand side and the impact of climate-induced crop yield changes on the supply side. Future crop yield changes were simulated by a process-based crop model driven with future climate projections from a regional climate model, and future changes of food demand is projected using a model for policy analysis of agricultural commodities and trade. The impact of human decision-making on land use was explicitly considered through multiple "what-if" scenarios to examine the range of uncertainties in projecting future land use. Without agricultural intensification, the climate-induced decrease of crop yield together with increase of food demand are found to cause a significant increase in agricultural land use at the expense of forest and grassland by the mid-century, and the resulting land use land cover changes are found to feed back to the regional climate in a way that exacerbates the negative impact of climate on crop yield. Analysis of results from multiple decision-making scenarios suggests that human adaptation characterized by science-informed decision making to minimize land use could be very effective in many parts of the region.

  11. Prescribing practice for malaria following introduction of artemether-lumefantrine in an urban area with declining endemicity in West Africa

    Directory of Open Access Journals (Sweden)

    Conway David J

    2010-06-01

    Full Text Available Abstract Background The decline in malaria coinciding with the introduction of newer, costly anti-malarials has prompted studies into the overtreatment for malaria mostly in East Africa. The study presented here describes prescribing practices for malaria at health facilities in a West African country. Methods Cross-sectional surveys were carried out in two urban Gambian primary health facilities (PHFs during and outside the malaria transmission season. Facilities were comparable in terms of the staffing compliment and capability to perform slide microscopy. Patients treated for malaria were enrolled after consultations and blood smears collected and read at a reference laboratory. Slide reading results from the PHFs were compared to the reference readings and the proportion of cases treated but with a negative test result at the reference laboratory was determined. Results Slide requests were made for 33.2% (173 of those enrolled, being more frequent in children (0-15 yrs than adults during the wet season (p = 0.003. In the same period, requests were commoner in under-fives compared to older children (p = 0.022; however, a positive test result was 4.4 times more likely in the latter group (p = 0.010. Parasitaemia was confirmed for only 4.7% (10/215 and 12.5% (37/297 of patients in the dry and wet seasons, respectively. The negative predictive value of a PHF slide remained above 97% in both seasons. Conclusions The study provides evidence for considerable overtreatment for malaria in a West African setting comparable to reports from areas with similar low malaria transmission in East Africa. The data suggest that laboratory facilities may be under-used, and that adherence to negative PHF slide results could significantly reduce the degree of overtreatment. The "peak prevalence" in 5-15 year olds may reflect successful implementation of malaria control interventions in under-fives, but point out the need to extend such interventions to older

  12. The spatial genetic differentiation of the legume pod borer, Maruca vitrata F. (Lepidoptera: Crambidae) populations in West Africa.

    Science.gov (United States)

    Agunbiade, T A; Coates, B S; Kim, K S; Forgacs, D; Margam, V M; Murdock, L L; Ba, M N; Binso-Dabire, C L; Baoua, I; Ishiyaku, M F; Tamò, M; Pittendrigh, B R

    2012-10-01

    The legume pod borer, Maruca vitrata, is an endemic insect pest that causes significant yield loss to the cowpea crop in West Africa. The application of population genetic tools is important in the management of insect pests but such data on M. vitrata is lacking. We applied a set of six microsatellite markers to assess the population structure of M. vitrata collected at five sites from Burkina Faso, Niger and Nigeria. Observed polymorphisms ranged from one (marker 3393) to eight (marker 32008) alleles per locus. Observed and expected heterozygosities ranged from 0.0 to 0.8 and 0.0 to 0.6, respectively. Three of the loci in samples from Nigeria and Burkina Faso deviated significantly from Hardy-Weinberg Equilibrium (HWE), whereas no loci deviated significantly in samples from Niger. Analysis of molecular variance (AMOVA) indicated that 67.3% level of the genetic variation was within individuals compared to 17.3% among populations. A global estimate of F ST=0.1 (ENA corrected F ST=0.1) was significant (P⩽0.05) and corroborated by pairwise F ST values that were significant among all possible comparisons. A significant correlation was predicted between genetic divergence and geographic distance between subpopulations (R2=0.6, P=0.04), and cluster analysis by the program STRUCTURE predicted that co-ancestry of genotypes were indicative of three distinct populations. The spatial genetic variance among M. vitrata in West Africa may be due to limited gene flow, south-north seasonal movement pattern or other reproductive barriers. This information is important for the cultural, chemical and biological control strategies for managing M. vitrata.

  13. Heterogeneity in District-Level Transmission of Ebola Virus Disease during the 2013-2015 Epidemic in West Africa.

    Directory of Open Access Journals (Sweden)

    Fabienne Krauer

    2016-07-01

    Full Text Available The Ebola virus disease (EVD epidemic in West Africa in 2013-2015 spread heterogeneously across the three hardest-hit countries Guinea, Liberia and Sierra Leone and the estimation of national transmission of EVD provides little information about local dynamics. To investigate district-level transmissibility of EVD, we applied a statistical modelling approach to estimate the basic reproduction number (R0 for each affected district and each country using weekly incident case numbers. We estimated growth rates during the early exponential phase of the outbreak using exponential regression of the case counts on the first eight weeks since onset. To take into account the heterogeneity between and within countries, we fitted a mixed effects model and calculated R0 based on the predicted individual growth rates and the reported serial interval distribution. At district level, R0 ranged from 0.36 (Dubréka to 1.72 (Beyla in Guinea, from 0.53 (Maryland to 3.37 (Margibi in Liberia and from 1.14 (Koinadugu to 2.73 (Western Rural in Sierra Leone. At national level, we estimated an R0 of 0.97 (95% CI 0.77-1.18 for Guinea, 1.26 (95% CI 0.98-1.55 for Liberia and 1.66 (95% CI 1.32-2.00 for Sierra Leone. Socio-demographic variables related to urbanisation such as high population density and high wealth index were found positively associated with R0 suggesting that the consequences of fast urban growth in West Africa may have contributed to the increased spread of EVD.

  14. Access to Risk Mitigating Weather Forecasts and Changes in Farming Operations in East and West Africa: Evidence from a Baseline Survey

    Directory of Open Access Journals (Sweden)

    Abayomi Samuel Oyekale

    2015-10-01

    Full Text Available Unfavorable weather currently ranks among the major challenges facing agricultural development in many African countries. Impact mitigation through access to reliable and timely weather forecasts and other adaptive mechanisms are foremost in Africa’s policy dialogues and socio-economic development agendas. This paper analyzed the factors influencing access to forecasts on incidence of pests/diseases (PD and start of rainfall (SR. The data were collected by Climate Change Agriculture and Food Security (CCAFS and analyzed with Probit regression separately for East Africa, West Africa and the combined dataset. The results show that 62.7% and 56.4% of the farmers from East and West Africa had access to forecasts on start of rainfall, respectively. In addition, 39.3% and 49.4% of the farmers from East Africa indicated that forecasts on outbreak of pests/diseases and start of rainfall were respectively accompanied with advice as against 18.2% and 41.9% for West Africa. Having received forecasts on start of rainfall, 24.0% and 17.6% of the farmers from East and West Africa made decisions on timing of farming activities respectively. Probabilities of having access to forecasts on PD significantly increased with access to formal education, farm income and previous exposure to climatic shocks. Furthermore, probabilities of having access to forecasts on SR significantly increased (p < 0.05 with access to business income, radio and perception of more erratic rainfall, among others. It was recommended that promotion of informal education among illiterate farmers would enhance their climatic resilience, among others.

  15. The impact of human conflict on the genetics of Mastomys natalensis and Lassa virus in West Africa.

    Directory of Open Access Journals (Sweden)

    Aude Lalis

    Full Text Available Environmental changes have been shown to play an important role in the emergence of new human diseases of zoonotic origin. The contribution of social factors to their spread, especially conflicts followed by mass movement of populations, has not been extensively investigated. Here we reveal the effects of civil war on the phylogeography of a zoonotic emerging infectious disease by concomitantly studying the population structure, evolution and demography of Lassa virus and its natural reservoir, the rodent Mastomys natalensis, in Guinea, West Africa. Analysis of nucleoprotein gene sequences enabled us to reconstruct the evolutionary history of Lassa virus, which appeared 750 to 900 years ago in Nigeria and only recently spread across western Africa (170 years ago. Bayesian demographic inferences revealed that both the host and the virus populations have gone recently through severe genetic bottlenecks. The timing of these events matches civil war-related mass movements of refugees and accompanying environmental degradation. Forest and habitat destruction and human predation of the natural reservoir are likely explanations for the sharp decline observed in the rodent populations, the consequent virus population decline, and the coincident increased incidence of Lassa fever in these regions. Interestingly, we were also able to detect a similar pattern in Nigeria coinciding with the Biafra war. Our findings show that anthropogenic factors may profoundly impact the population genetics of a virus and its reservoir within the context of an emerging infectious disease.

  16. Relative severity of aflatoxin contamination of cereal crops in West Africa.

    Science.gov (United States)

    Bandyopadhyay, Ranajit; Kumar, Manjula; Leslie, John F

    2007-10-01

    Aflatoxins are a common contaminant of cereals that can cause cancer, liver disease, immune suppression, retarded growth and development, and death, depending on the level and duration of exposure. Maize is an introduced crop to Africa and there have been efforts over the last 20 years or so to replace traditional cereal crops, such as sorghum (Sorghum bicolor) and pearl millet (Pennisetum glaucum), with maize. We found that maize was significantly more heavily colonized by aflatoxin-producing Aspergillus spp. than either sorghum or millet, with overall aflatoxin levels being correspondingly higher. On average, Nigerians consume 138 kg cereals annually. If the primary cereal is sorghum instead of maize, then the risk of aflatoxin-related problems is reduced 4-fold; if it is pearl millet, then the risks are reduced 8-fold. Development programs and other ventures to increase maize production in marginal cropping areas of Africa should be reconsidered and, instead, efforts to improve/maintain traditional crops encouraged.

  17. Morphological Characterization of African Bush Mango trees (Irvingia species) in the Dahomey Gap (West Africa)

    NARCIS (Netherlands)

    Vihotogbe, R.; Berg, van den R.G.; Sosef, M.S.M.

    2013-01-01

    The variation of the morphological characters of bitter and sweet African bush mango trees (Irvingia species) was investigated in the Dahomey Gap which is the West African savannah woodland area separating the Upper and the Lower Guinean rain forest blocks. African bush mangoes have been rated as th

  18. Land Tenure and the Potential for the Adoption of Alley Farming in West Africa

    OpenAIRE

    Lawry, S; Steinberger, D; Jabbar, Mohammad A.

    1994-01-01

    Alley farming was developed as a means of maintaining soil fertility in fields under permanent cultivation in Africa, as population pressure makes the traditional practice of slash-and-burn combined with fallowing unsustainable. It is an agroforestry system under which food crops are grown in alleys formed by hedgerows of leguminous trees and shrubs. Studies have shown that it works, but farmers are only taking it up very slowly. Recent work suggests that land tenure might be a factor in the ...

  19. Epidemiology of Syphilis in regional blood transfusion centres in Burkina Faso, West Africa

    OpenAIRE

    Bisseye, Cyrille; Sanou, Mahamoudou; Nagalo, Bolni Marius; Kiba, Alice; Compaoré, Tegwindé Rebeca; Tao, Issoufou; Simpore, Jacques

    2013-01-01

    Introduction Syphilis remains a major public health problem in sub-Saharan Africa, including Burkina Faso. However, few published data are available on the prevalence of syphilis in the general population. This study had two main objectives: to determine the seroprevalence of syphilis in a cohort of 37,210 first time blood donors and to study socio-demographic factors associated with the risk of infection by Treponema pallidum. Methods Antibodies to Treponema pallidum were screened for, by us...

  20. Improvement and Comparative Assessment of a New Hydrological Modelling Approach for the Ouémé River Basin (Bénin), West Africa

    Science.gov (United States)

    GABA, C. O. U.

    2015-12-01

    Assessing water resources is still an important issue especially in the context of climatic changes. Although numerous hydrological models exist, new approaches are still under investigation. In this context, we propose a new modelling approach based on the Physics Principle of Least Action. A first version of a Least Action based model, in its deterministic version has already given very good results on simulating the Bétérou catchment in the Ouémé basin, Benin. The paper presents new hypotheses to go further in the model development with a view of widening its application. The improved version of the model MODYPMA was applied on 22 subcatchments in Africa, in Bénin, Côte d'Ivoire, Ethiopia; in Europe, and in the USA. Its performance was compared to two well known lumped conceptual models, the GR4J and HBV models. The model could be successfully calibrated and validated; it shows a good performance for a range of scales but a limited applicability to catchments smaller than 500 km2 . The analysis revealed that the three models have similar performance and timing errors. The parameter uncertainty was analysed using the GLUE methodology. It is concluded that model uncertainty is higher during high flows and that uncertainty analysis should include the uncertainty of the discharge data. Finally, some aspects that further research must address are brought out.

  1. Transactional sex and sexual harassment between professors and students at an urban university in Benin.

    Science.gov (United States)

    Eller, Amanda

    2016-07-01

    This paper adds to discussion of transactional sex relationships in Africa by examining the distinction between transactional sex and sexual harassment in the context of professor-student relationships and their inherent power dynamics. By exploring the ways in which female university students in urban Benin toe the line between empowered agent and victim, I show how the power differential between professor and student obstructs the professor's ability to objectively determine consent, and examine why, in spite of this differential, male professors are frequently perceived as the victims of these relationships. Ethnographic data were gathered through participant observation on a public university campus in Benin and in-depth interviews and focus groups with 34 students and 5 professors from that university. Findings suggest that the problem of sexual harassment on campus will be difficult to address so long as transactional sex relationships between professors and students are permitted to continue. PMID:26808397

  2. Processes underpinning development and maintenance of diversity in rice in West Africa: evidence from combining morphological and molecular markers.

    Directory of Open Access Journals (Sweden)

    Alfred Mokuwa

    Full Text Available We assessed the interplay of artificial and natural selection in rice adaptation in low-input farming systems in West Africa. Using 20 morphological traits and 176 molecular markers, 182 farmer varieties of rice (Oryza spp. from 6 West African countries were characterized. Principal component analysis showed that the four botanical groups (Oryza sativa ssp. indica, O. sativa ssp. japonica, O. glaberrima, and interspecific farmer hybrids exhibited different patterns of morphological diversity. Regarding O. glaberrima, morphological and molecular data were in greater conformity than for the other botanical groups. A clear difference in morphological features was observed between O. glaberrima rices from the Togo hills and those from the Upper Guinea Coast, and among O. glaberrima rices from the Upper Guinea Coast. For the other three groups such clear patterns were not observed. We argue that this is because genetic diversity is shaped by different environmental and socio-cultural selection pressures. For O. glaberrima, recent socio-cultural selection pressures seemed to restrict genetic diversity while this was not observed for the other botanical groups. We also show that O. glaberrima still plays an important role in the selection practices of farmers and resulting variety development pathways. This is particularly apparent in the case of interspecific farmer hybrids where a relationship was found between pericarp colour, panicle attitude and genetic diversity. Farmer varieties are the product of long and complex trajectories of selection governed by local human agency. In effect, rice varieties have emerged that are adapted to West African farming conditions through genotype × environment × society interactions. The diversity farmers maintain in their rice varieties is understood to be part of a risk-spreading strategy that also facilitates successful and often serendipitous variety innovations. We advocate, therefore, that farmers and

  3. First report of sylvatic DENV-2-associated dengue hemorrhagic fever in West Africa.

    OpenAIRE

    Leticia Franco; Gustavo Palacios; José Antonio Martinez; Ana Vázquez; Nazir Savji; Fernando De Ory; María Paz Sanchez-Seco; Dolores Martín; W Ian Lipkin; Antonio Tenorio

    2011-01-01

    Dengue virus (DENV) circulates in human and sylvatic cycles. Sylvatic strains are both ecologically and evolutionarily distinct from endemic viruses. Although sylvatic dengue cycles occur in West African countries and Malaysia, only a few cases of mild human disease caused by sylvatic strains and one single case of dengue hemorrhagic fever in Malaysia have been reported. Here we report a case of dengue hemorrhagic fever (DHF) with thrombocytopenia (13000/µl), a raised hematocrit (32% above ba...

  4. Pan-African Paleostresses and Reactivation of the Eburnean Basement Complex in Southeast Ghana (West Africa

    Directory of Open Access Journals (Sweden)

    Mahaman Sani Tairou

    2012-01-01

    Full Text Available This faulting tectonics analysis concerns the southernmost segment of the Dahomeyide Orogen and the West-African craton eastern margin in southeast Ghana. The analysis of strike-slip faults in the frontal units of the Dahomeyide Belt indicates that four distinct compressive events (NE-SW, ENE-WSW to E-W, ESE-WNW to SE-NW and SE-NW to SSE-NNW originated the juxtaposition of the Pan-African Mobile Zone and the West-African craton. These paleostress systems define a clockwise rotation of the compressional axis during the structuring of the Dahomeyide Orogen (650–550 Ma. The SE-NW and SSE-NNW to N-S compressional axes in the cratonic domain and its cover (Volta Basin suggest that the reactivation of the eastern edge of the West African craton is coeval with the last stages of the Pan-African tectogenesis in southeast Ghana. An extensional episode expressed as late normal faulting is also recorded in this study. This E-W to SE-NW extension, which is particular to the southernmost part of the Dahomeyide Belt, appears to be post-Pan-African. This extension probably contributed to the formation of a major Jurassic rifting zone that originated the Central Atlantic and the Benue Trough.

  5. RELATION BETWEEN GLOBAL RADIATION AND FOOD PRODUCTION IN A HUMID TROPICAL CLIMATE OF WEST AFRICA

    Directory of Open Access Journals (Sweden)

    Chineke THEO CHIDIEZIE

    2006-02-01

    Full Text Available Obvious is the fact that globally the climate is changing. Solar energy and water availability are the key factors affecting agricultural productivity in Subtropical Africa. In this paper is presented the global radiation for Owerri, Nigeria (latitude 5.48oN, longitude 7.03oE between 1985-1997 which has a mean annual value of 76.17 W/m2 per day. With appropriate crop specie selection and management, food production, including poultry output can be boosted in this high solar radiation area. The introduction of solar egg incubator, solar manure dryer and brooder has been strongly advocated.

  6. West African pholcid spiders: an overview, with descriptions of five new species (Araneae, Pholcidae

    Directory of Open Access Journals (Sweden)

    Bernhard A. Huber

    2013-10-01

    Full Text Available This paper summarizes current knowledge about West African pholcids. West Africa is here defined as the area south of 17°N and west of 5°E, including mainly the Upper Guinean subregion of the Guineo-Congolian center of endemism. This includes all of Senegal, The Gambia, Guinea Bissau, Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana, Togo and Benin. An annotated list of the 14 genera and 38 species recorded from this area is given, together with distribution maps and an identification key to genera. Five species are newly described: Anansus atewa sp. nov., Artema bunkpurugu sp. nov., Leptopholcus kintampo sp. nov., Spermophora akwamu sp. nov., and S. ziama sp. nov. The female of Quamtana kitahurira is newly described. Additional new records are given for 16 previously described species, including 33 new country records. Distribution patterns of West African pholcids are discussed, as well as possible explanations for relatively low West African pholcid species diversity as compared to Central and East Africa.

  7. Reviving the African wolf Canis lupus lupaster in North and West Africa : a mitochondrial lineage ranging more than 6,000 km wide

    OpenAIRE

    Philippe Gaubert; Cécile Bloch; Slim Benyacoub; Adnan Abdelhamid; Paolo Pagani; Chabi Adéyèmi Marc Sylvestre Djagoun; Arnaud Couloux; Sylvain Dufour

    2012-01-01

    The recent discovery of a lineage of gray wolf in North-East Africa suggests the presence of a cryptic canid on the continent, the African wolf Canis lupus lupaster. We analyzed the mtDNA diversity (cytochrome b and control region) of a series of African Canis including wolf-like animals from North and West Africa. Our objectives were to assess the actual range of C. l. lupaster, to further estimate the genetic characteristics and demographic history of its lineage, and to question its taxono...

  8. Uses, traditional management, perception of variation and preferences in ackee (Blighia sapida K.D. Koenig fruit traits in Benin: implications for domestication and conservation

    Directory of Open Access Journals (Sweden)

    Eyog-Matig Oscar

    2010-03-01

    Full Text Available Abstract Background Blighia sapida is a woody perennial multipurpose fruit tree species native to the Guinean forests of West Africa. The fleshy arils of the ripened fruits are edible. Seeds and capsules of the fruits are used for soap-making and all parts of the tree have medicinal properties. Although so far overlooked by researchers in the region, the tree is highly valued by farmers and is an important component of traditional agroforestry systems in Benin. Fresh arils, dried arils and soap are traded in local and regional markets in Benin providing substantial revenues for farmers, especially women. Recently, ackee has emerged as high-priority species for domestication in Benin but information necessary to elaborate a clear domestication strategy is still very sketchy. This study addresses farmers' indigenous knowledge on uses, management and perception of variation of the species among different ethnic groups taking into account also gender differences. Methods 240 randomly selected persons (50% women belonging to five different ethnic groups, 5 women active in the processing of ackee fruits and 6 traditional healers were surveyed with semi-structured interviews. Information collected refer mainly to the motivation of the respondents to conserve ackee trees in their land, the local uses, the perception of variation, the preference in fruits traits, the management practices to improve the production and regenerate ackee. Results People have different interests on using ackee, variable knowledge on uses and management practices, and have reported nine differentiation criteria mainly related to the fruits. Ackee phenotypes with preferred fruit traits are perceived by local people to be more abundant in managed in-situ and cultivated stands than in unmanaged wild stands, suggesting that traditional management has initiated a domestication process. As many as 22 diseases have been reported to be healed with ackee. In general, indigenous

  9. Test of validity of a dynamic soil carbon model using data from leaf litter decomposition in a West African tropical forest

    Directory of Open Access Journals (Sweden)

    G. H. S. Guendehou

    2013-05-01

    Full Text Available We evaluated the applicability of the dynamic soil carbon model Yasso07 in tropical conditions in West Africa by simulating the litter decomposition process using as required input into the model litter mass, litter quality, temperature and precipitation collected during a litterbag experiment. The experiment was conducted over a six-month period on leaf litter of five dominant tree species, namely Afzelia africana, Anogeissus leiocarpa, Ceiba pentandra, Dialium guineense and Diospyros mespiliformis in a semi-deciduous vertisol forest in Southern Benin. Since the predictions of Yasso07 were not consistent with the observations on mass loss and chemical composition of litter, Yasso07 was fitted to the dataset composed of global data and the new experimental data from Benin. The re-parameterized versions of Yasso07 had a good predictive ability and refined the applicability of the model in Benin to estimate soil carbon stocks, its changes and CO2 emissions from heterotrophic respiration as main outputs of the model. The findings of this research support the hypothesis that the high variation of litter quality observed in the tropics is a major driver of the decomposition and needs to be accounted in the model parameterization.

  10. Euros vs. yuan: comparing European and Chinese fishing access in West Africa.

    Science.gov (United States)

    Belhabib, Dyhia; Sumaila, U Rashid; Lam, Vicky W Y; Zeller, Dirk; Le Billon, Philippe; Abou Kane, Elimane; Pauly, Daniel

    2015-01-01

    We compare the performance of European Union (EU) and Chinese fisheries access agreements with West African countries in terms of illegal and unreported fishing, economic equity, and patterns of exploitation. Bottom-up re-estimations of catch reveal that the EU (1.6 million t•year(-1)) and China (2.3 million t•year(-1)) report only 29% and 8%, respectively, of their estimated total catches (including estimated discards whenever possible) from West African countries between 2000 and 2010. EU catches are declining, while Chinese catches are increasing and are yet to reach the historic maximum level of EU catches (3 million t•year(-1) on average in the 1970s-1980s). The monetary value of EU fishing agreements, correlated in theory with reported catches, is straightforward to access, in contrast to Chinese agreements. However, once quantified, the value of Chinese agreements is readily traceable within the African economy through the different projects they directly cover, in contrast to the funds disbursed [to host governments] by the EU. Overall, China provides resources equivalent to about 4% of the ex-vessel value [value at landing] of the catch taken by Chinese distant-water fleets from West African waters, while the EU pays 8%. We address the difficulties of separating fees directly related to fishing from other economic or political motivations for Chinese fees, which could introduce a bias to the present findings as this operation is not performed for EU access fees officially related to fishing. Our study reveals that the EU and China perform similarly in terms of illegal fishing, patterns of exploitation and sustainability of resource use, while under-reporting by the EU increases and that by China decreases. The EU agreements provide, in theory, room for improving scientific research, monitoring and surveillance, suggesting a better performance than for Chinese agreements, but the end-use of the EU funds are more difficult, and sometime impossible to

  11. Euros vs. yuan: comparing European and Chinese fishing access in West Africa.

    Directory of Open Access Journals (Sweden)

    Dyhia Belhabib

    Full Text Available We compare the performance of European Union (EU and Chinese fisheries access agreements with West African countries in terms of illegal and unreported fishing, economic equity, and patterns of exploitation. Bottom-up re-estimations of catch reveal that the EU (1.6 million t•year(-1 and China (2.3 million t•year(-1 report only 29% and 8%, respectively, of their estimated total catches (including estimated discards whenever possible from West African countries between 2000 and 2010. EU catches are declining, while Chinese catches are increasing and are yet to reach the historic maximum level of EU catches (3 million t•year(-1 on average in the 1970s-1980s. The monetary value of EU fishing agreements, correlated in theory with reported catches, is straightforward to access, in contrast to Chinese agreements. However, once quantified, the value of Chinese agreements is readily traceable within the African economy through the different projects they directly cover, in contrast to the funds disbursed [to host governments] by the EU. Overall, China provides resources equivalent to about 4% of the ex-vessel value [value at landing] of the catch taken by Chinese distant-water fleets from West African waters, while the EU pays 8%. We address the difficulties of separating fees directly related to fishing from other economic or political motivations for Chinese fees, which could introduce a bias to the present findings as this operation is not performed for EU access fees officially related to fishing. Our study reveals that the EU and China perform similarly in terms of illegal fishing, patterns of exploitation and sustainability of resource use, while under-reporting by the EU increases and that by China decreases. The EU agreements provide, in theory, room for improving scientific research, monitoring and surveillance, suggesting a better performance than for Chinese agreements, but the end-use of the EU funds are more difficult, and sometime

  12. Euros vs. yuan: comparing European and Chinese fishing access in West Africa.

    Science.gov (United States)

    Belhabib, Dyhia; Sumaila, U Rashid; Lam, Vicky W Y; Zeller, Dirk; Le Billon, Philippe; Abou Kane, Elimane; Pauly, Daniel

    2015-01-01

    We compare the performance of European Union (EU) and Chinese fisheries access agreements with West African countries in terms of illegal and unreported fishing, economic equity, and patterns of exploitation. Bottom-up re-estimations of catch reveal that the EU (1.6 million t•year(-1)) and China (2.3 million t•year(-1)) report only 29% and 8%, respectively, of their estimated total catches (including estimated discards whenever possible) from West African countries between 2000 and 2010. EU catches are declining, while Chinese catches are increasing and are yet to reach the historic maximum level of EU catches (3 million t•year(-1) on average in the 1970s-1980s). The monetary value of EU fishing agreements, correlated in theory with reported catches, is straightforward to access, in contrast to Chinese agreements. However, once quantified, the value of Chinese agreements is readily traceable within the African economy through the different projects they directly cover, in contrast to the funds disbursed [to host governments] by the EU. Overall, China provides resources equivalent to about 4% of the ex-vessel value [value at landing] of the catch taken by Chinese distant-water fleets from West African waters, while the EU pays 8%. We address the difficulties of separating fees directly related to fishing from other economic or political motivations for Chinese fees, which could introduce a bias to the present findings as this operation is not performed for EU access fees officially related to fishing. Our study reveals that the EU and China perform similarly in terms of illegal fishing, patterns of exploitation and sustainability of resource use, while under-reporting by the EU increases and that by China decreases. The EU agreements provide, in theory, room for improving scientific research, monitoring and surveillance, suggesting a better performance than for Chinese agreements, but the end-use of the EU funds are more difficult, and sometime impossible to

  13. Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

    Directory of Open Access Journals (Sweden)

    C. E. Reeves

    2010-03-01

    Full Text Available During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons and points to some of the important findings discussed in more detailed in other papers in this special issue.

    The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of O3-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the Southern Hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow.

    Mineral dust was found to be the most abundant and ubiquitous aerosol type in the

  14. Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

    Science.gov (United States)

    Reeves, C. E.; Formenti, P.; Afif, C.; Ancellet, G.; Attié, J.-L.; Bechara, J.; Borbon, A.; Cairo, F.; Coe, H.; Crumeyrolle, S.; Fierli, F.; Flamant, C.; Gomes, L.; Hamburger, T.; Jambert, C.; Law, K. S.; Mari, C.; Jones, R. L.; Matsuki, A.; Mead, M. I.; Methven, J.; Mills, G. P.; Minikin, A.; Murphy, J. G.; Nielsen, J. K.; Oram, D. E.; Parker, D. J.; Richter, A.; Schlager, H.; Schwarzenboeck, A.; Thouret, V.

    2010-08-01

    During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA) project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons) and points to some of the important findings discussed in more detail in other papers in this special issue. The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of ozone-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the southern hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow. Mineral dust was found to be the most abundant and ubiquitous aerosol type in the atmosphere over Western Africa. Data

  15. Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

    Directory of Open Access Journals (Sweden)

    C. E. Reeves

    2010-08-01

    Full Text Available During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons and points to some of the important findings discussed in more detail in other papers in this special issue.

    The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of ozone-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the southern hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow.

    Mineral dust was found to be the most abundant and ubiquitous aerosol type in the

  16. Catalyzing Gender Equality-Focused Clean Energy Development in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    2016-06-01

    The Economic Community of West African States (ECOWAS) Regional Center for Renewable Energy and Energy Efficiency (ECREEE) partnered with the Clean Energy Solutions Center (Solutions Center), the African Development Bank and other institutions to develop a Situation Analysis of Energy and Gender Issues in ECOWAS Member States. Through a systematic approach to assess interlinked gender and energy issues in the region, the report puts forth a number of key findings. This brochure highlights ECREEE's partnership with the Solutions Center and key findings from the report.

  17. Improving livelihoods in West Africa through a natural resource - The case of Parkia biglobosa and soumbala

    DEFF Research Database (Denmark)

    Kronborg, Mette

    In this thesis we bridge the gap between science and international development work by looking into the life improving prospects of the natural resource Parkia biglobosa. Parkia biglobosa is important for economic and subsistence reasons in Burkina Faso. However, P. biglobosa and its associated......-west Burkina Faso together with the women organisation Mousso Ta Yiri. These plantations will soon be CO2 certified through the certification organisation Plan Vivo. The economic benefits associated with the P. biglobosa plantations will be two-sided; women will get an extra income from soumbala sale...

  18. Soil carbon and plant diversity distribution at the farm level in the savannah region of Northern Togo (West Africa

    Directory of Open Access Journals (Sweden)

    M.-T. Sebastià

    2008-10-01

    Full Text Available In western Africa, soil organic matter is a source of fertility for food provision and a tool for climate mitigation. In the Savannah region, strong soil degradation linked to an increase in population threatens organic matter conservation and agricultural yield. Soil degradation is also expected to impact biodiversity and, with it, increase the vulnerability of ecosystem goods and services, including the storage of soil organic carbon. Studies of land use, plant species composition and soil fertility were conducted for a conservation project at a demonstration farm in Northern Togo (West Africa, host to various management regimes. Results showed a low organic matter content of the surface soil horizons, often around 0.5%. The highest values were found in a sacred forest within the farm (2.2%. Among crops, rice had the highest soil organic matter, around 1%. In a survey of grasslands, pastures showed the highest organic matter content, with vegetation composition differing from grazed fallows and abandoned grasslands. Plant species richness showed a positive relationship with soil organic matter (R2adj=41.2%, but only by the end of the wet season, when species richness was also highest. Sampling date had a strong effect on vegetation composition. Results showed a strong influence of human activity on soil formation and distribution, and also on plant diversity. The soil characteristics found under the permanent forest suggest a high potential of the soils of the region for improvement of both agricultural yields and as a potential carbon sink relevant to global change policies.

  19. Wetland plant communities in the Potchefstroom Municipal Area, North-West, South Africa

    Directory of Open Access Journals (Sweden)

    S. S. Cilliers

    1998-12-01

    Full Text Available Wetlands in natural areas in South Africa have been described before, but no literature exists concerning the phyto­sociology of urban wetlands. The objective of this study was to conduct a complete vegetation analysis of the wetlands in the Potchefstroom Municipal Area. Using a numerical classification technique (TWINSPAN as a first approximation, the classification was refined by using Braun-Blanquet procedures. The result is a phytosociological table from which a number of unique plant communities are recognised. These urban wetlands are characterised by a high species diversity, which is unusual for wetlands. Reasons for the high species diversity could be the different types of disturbances occurring in this area. Results of this study can be used to construact more sensible management practises for these wetlands.  

  20. Solid waste characterization in Kétao, a rural town in Togo, West Africa

    DEFF Research Database (Denmark)

    Edjabou, Vincent Maklawe Essonanawe; Møller, Jacob; Christensen, Thomas Højlund

    2012-01-01

    In Africa the majority of solid waste data is for big cities. Small and rural towns are generally neglected and waste data from these areas are often unavailable, which makes planning a proper solid waste management difficult. This paper presents the results from two waste characterization projects...... conducted in Kétao, a rural town in Togo during the rainy season and the dry season in 2010. The seasonal variation has a significant impact on the waste stream. The household waste generation rate was estimated at 0.22 kg person−1 day−1 in the dry season and 0.42 in the rainy season. Likewise, the waste...... moisture content was 4% in the dry season while it was 33–63% in the rainy season. The waste consisted mainly of soil and dirt characterized as ‘other’ (41%), vegetables and putrescibles (38%) and plastic (11%). In addition to these fractions, considerable amounts of material are either recycled or reused...

  1. Ebola Virus Disease Epidemic: What Can the World Learn and Not Learn from West Africa?

    Directory of Open Access Journals (Sweden)

    Romuladus E. Azuine, DrPH, RN

    2015-03-01

    Full Text Available WITH over 4,500 deaths and counting, and new cases identified in two developed countries that are struggling and faltering in their handling of the epidemic, the 2014 Ebola Virus Disease (EVD epidemic is unlike any of its kind ever encountered. The ability of some poor, resource-limited, developing countries in sub-Saharan Africa to efficiently handle the epidemic within their shores provides some lessons learned for the global health community. Among others, the 2014 EVD epidemic teaches us that it is time to put the “P” back in public and population health around the world. The global health community must support a sustainable strategy to mitigate Ebola virus and other epidemics both within and outside their shores, even after the cameras are gone. Ebola virus must not be called the disease of the poor and developing world.

  2. Non-falciparum malaria infections in pregnant women in West Africa

    DEFF Research Database (Denmark)

    Williams, John; Njie, Fanta; Cairns, Matthew;

    2016-01-01

    BACKGROUND: Non-Plasmodium falciparum malaria infections are found in many parts of sub-Saharan Africa but little is known about their importance in pregnancy. METHODS: Blood samples were collected at first antenatal clinic attendance from 2526 women enrolled in a trial of intermittent screening...... and treatment of malaria in pregnancy (ISTp) versus intermittent preventive treatment (IPTp) conducted in Burkina Faso, The Gambia, Ghana and Mali. DNA was extracted from blood spots and tested for P. falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium ovale using a nested PCR test. Risk...... factors for a non-falciparum malaria infection were investigated and the influence of these infections on the outcome of pregnancy was determined. RESULTS: P. falciparum infection was detected frequently (overall prevalence by PCR: 38.8 %, [95 % CI 37.0, 40.8]), with a prevalence ranging from 10.8 % in...

  3. Non-falciparum malaria infections in pregnant women in West Africa

    DEFF Research Database (Denmark)

    Williams, John; Njie, Fanta; Cairns, Matthew;

    2016-01-01

    and treatment of malaria in pregnancy (ISTp) versus intermittent preventive treatment (IPTp) conducted in Burkina Faso, The Gambia, Ghana and Mali. DNA was extracted from blood spots and tested for P. falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium ovale using a nested PCR test. Risk factors......BACKGROUND: Non-Plasmodium falciparum malaria infections are found in many parts of sub-Saharan Africa but little is known about their importance in pregnancy. METHODS: Blood samples were collected at first antenatal clinic attendance from 2526 women enrolled in a trial of intermittent screening...... for a non-falciparum malaria infection were investigated and the influence of these infections on the outcome of pregnancy was determined. RESULTS: P. falciparum infection was detected frequently (overall prevalence by PCR: 38.8 %, [95 % CI 37.0, 40.8]), with a prevalence ranging from 10.8 % in The Gambia...

  4. Triple Helix of university-industry-government relationships in West Africa

    Directory of Open Access Journals (Sweden)

    Eustache Mêgnigbêto

    2013-01-01

    Full Text Available The West African countries′ scientific publications data are downloaded from Web of Science. Analyses focus on university-industry-government collaboration. We compute data on each sector′s production and collaboration among them. Particularly, the industrial production is extracted; the network, it induces is built and its structure analyzed with social network analysis methods and techniques, using Pajek. Results show that the university is the biggest information producer, followed by government; the number of industrial publications is meaningless; even some countries have no industrial output. Consequently, collaboration between the university and government is more visible. Collaboration between the three Triple Helix spheres occurred only in Nigeria. The mutual information between university, industry, and government is weak, illustrating the low level of knowledge flow between innovation actors in the region. These results could explain the negligible share of the developing countries in general and African and West African countries particularly to the World economy, and also the low level of development the region.

  5. Chinese Public Attention to the Outbreak of Ebola in West Africa: Evidence from the Online Big Data Platform

    Science.gov (United States)

    Liu, Kui; Li, Li; Jiang, Tao; Chen, Bin; Jiang, Zhenggang; Wang, Zhengting; Chen, Yongdi; Jiang, Jianmin; Gu, Hua

    2016-01-01

    Objective: The outbreak of the Ebola epidemic in West Africa in 2014 exerted enormous global public reaction via the Internet and social media. This study aimed to investigate and evaluate the public reaction to Ebola in China and identify the primitive correlation between possible influence factors caused by the outbreak of Ebola in West Africa and Chinese public attention via Internet surveillance. Methods: Baidu Index (BDI) and Sina Micro Index (SMI) were collected from their official websites, and the disease-related data were recorded from the websites of the World Health Organization (WHO), U.S. Centers for Disease Control and Prevention (CDC), and U.S. National Ministries of Health. The average BDI of Internet users in different regions were calculated to identify the public reaction to the Ebola outbreak. Spearman’s rank correlation was used to check the relationship of epidemic trends with BDI and SMI. Additionally, spatio-temporal analysis and autocorrelation analysis were performed to detect the clustered areas with the high attention to the topic of “Ebola”. The related news reports were collected from authoritative websites to identify potential patterns. Results: The BDI and the SMI for “Ebola” showed a similar fluctuating trend with a correlation coefficient = 0.9 (p < 0.05). The average BDI in Beijing, Tibet, and Shanghai was higher than other cities. However, the disease-related indicators did not identify potential correlation with both indices above. A hotspot area was detected in Tibet by local autocorrelation analysis. The most likely cluster identified by spatiotemporal cluster analysis was in the northeast regions of China with the relative risk (RR) of 2.26 (p ≤ 0.01) from 30 July to 14 August in 2014. Qualitative analysis indicated that negative news could lead to a continuous increase of the public’s attention until the appearance of a positive news report. Conclusions: Confronted with the risk of cross-border transmission of

  6. Regional Climate Simulations with COSMO-CLM for West Africa using three different soil-vegetation-atmosphere-transfer (SVAT) module

    Science.gov (United States)

    Breil, Marcus; Panitz, Hans-Jürgen

    2014-05-01

    Climate predictions on decadal timescales constitute a new field of research, closing the gap between short-term and seasonal weather predictions and long-term climate projections. Therefore, the Federal Ministry of Education and Research in Germany (BMBF) has recently funded the research program MiKlip (Mittelfristige Klimaprognosen), which aims to create a model system that can provide reliable decadal climate forecasts. Recent studies have suggested that one region with high potential decadal predictability is West Africa. Therefore, the project DEPARTURE (DEcadal Prediction of African Rainfall and ATlantic HURricanE Activity) was established within the MiKlip program to assess the feasibility and the potential added value of regional decadal climate predictions for West Africa. To quantify the potential decadal climate predictability, a multi-model approach with the three different regional climate models REMO, WRF and COSMO-CLM (CCLM) will be realized. The presented research will contribute to DEPARTURE by performing hindcast ensemble simulations with CCLM, driven by global decadal MPI-ESM-LR simulations. Thereby, one focus is on the dynamic soil-vegetation-climate interaction on decadal timescales. Recent studies indicate that there are significant feedbacks between the land-surface and the atmosphere, which might influence the decadal climate variability substantially. To investigate this connection, two different SVATs (Community Land Model (CLM), and VEG3D) will be coupled with the CCLM, replacing TERRA_ML, the standard SVAT implemented in CCLM. Thus, sensitive model parameters shall be identified, whereby the understanding of important processes might be improved. As a first step, TERRA_ML is substituted by VEG3D, a SVAT developed at the IMK-TRO, Karlsruhe, Germany. Compared to TERRA_ML, VEG3D includes an explicit vegetation layer by using a big leaf approach, inducing higher correlations with observations as it has been shown in previous studies. The

  7. Chinese Public Attention to the Outbreak of Ebola in West Africa: Evidence from the Online Big Data Platform

    Science.gov (United States)

    Liu, Kui; Li, Li; Jiang, Tao; Chen, Bin; Jiang, Zhenggang; Wang, Zhengting; Chen, Yongdi; Jiang, Jianmin; Gu, Hua

    2016-01-01

    Objective: The outbreak of the Ebola epidemic in West Africa in 2014 exerted enormous global public reaction via the Internet and social media. This study aimed to investigate and evaluate the public reaction to Ebola in China and identify the primitive correlation between possible influence factors caused by the outbreak of Ebola in West Africa and Chinese public attention via Internet surveillance. Methods: Baidu Index (BDI) and Sina Micro Index (SMI) were collected from their official websites, and the disease-related data were recorded from the websites of the World Health Organization (WHO), U.S. Centers for Disease Control and Prevention (CDC), and U.S. National Ministries of Health. The average BDI of Internet users in different regions were calculated to identify the public reaction to the Ebola outbreak. Spearman’s rank correlation was used to check the relationship of epidemic trends with BDI and SMI. Additionally, spatio-temporal analysis and autocorrelation analysis were performed to detect the clustered areas with the high attention to the topic of “Ebola”. The related news reports were collected from authoritative websites to identify potential patterns. Results: The BDI and the SMI for “Ebola” showed a similar fluctuating trend with a correlation coefficient = 0.9 (p disease-related indicators did not identify potential correlation with both indices above. A hotspot area was detected in Tibet by local autocorrelation analysis. The most likely cluster identified by spatiotemporal cluster analysis was in the northeast regions of China with the relative risk (RR) of 2.26 (p ≤ 0.01) from 30 July to 14 August in 2014. Qualitative analysis indicated that negative news could lead to a continuous increase of the public’s attention until the appearance of a positive news report. Conclusions: Confronted with the risk of cross-border transmission of the infectious disease, online surveillance might be used as an innovative approach to perform

  8. High Resolution Simulations of Future Climate in West Africa Using a Variable-Resolution Atmospheric Model

    Science.gov (United States)

    Adegoke, J. O.; Engelbrecht, F.; Vezhapparambu, S.

    2013-12-01

    In previous work demonstrated the application of a var¬iable-resolution global atmospheric model, the conformal-cubic atmospheric model (CCAM), across a wide range of spatial and time scales to investigate the ability of the model to provide realistic simulations of present-day climate and plausible projections of future climate change over sub-Saharan Africa. By applying the model in stretched-grid mode the versatility of the model dynamics, numerical formulation and physical parameterizations to function across a range of length scales over the region of interest, was also explored. We primarily used CCAM to illustrate the capability of the model to function as a flexible downscaling tool at the climate-change time scale. Here we report on additional long term climate projection studies performed by downscaling at much higher resolutions (8 Km) over an area that stretches from just south of Sahara desert to the southern coast of the Niger Delta and into the Gulf of Guinea. To perform these simulations, CCAM was provided with synoptic-scale forcing of atmospheric circulation from 2.5 deg resolution NCEP reanalysis at 6-hourly interval and SSTs from NCEP reanalysis data uses as lower boundary forcing. CCAM 60 Km resolution downscaled to 8 Km (Schmidt factor 24.75) then 8 Km resolution simulation downscaled to 1 Km (Schmidt factor 200) over an area approximately 50 Km x 50 Km in the southern Lake Chad Basin (LCB). Our intent in conducting these high resolution model runs was to obtain a deeper understanding of linkages between the projected future climate and the hydrological processes that control the surface water regime in this part of sub-Saharan Africa.

  9. Negative density dependence of sympatric Hinge-back Tortoises (Kinixys erosa and K. homeana in West Africa

    Directory of Open Access Journals (Sweden)

    Luca Luiselli

    2008-05-01

    Full Text Available A series of 59 transect surveys was conducted in selected wet forest habitats, along the coast of West Africa, to estimate the density distribution of African Hinge-back tortoises (Kinixys homeana and K. erosa. Line transect data were fed into a simple model to derive a detection function. The parameters estimated by the model produced an elaborate characterisation of tortoise distribution, which proved to be useful in the formulation of hypotheses about tortoise densities. Line transect data were analysed by DISTANCE, with a series of key and the series adjustment: the uniform function, the 1-parameter half-normal function, and the 2-parameter hazard-rate function were considered as key functions; the cosine series, simple polynomials, and Hermite polynomials were considered as series expansions. The detection function was estimated separately for Kinixys homeana and K. erosa, and for transects grouped for each study area by considering all the combinations of the above key functions and series expansions. The Akaike Information Criterion (AIC was computed for each candidate model and used for model selection. The best model of the detection function, for both the tortoise species was the uniform function with no series expansion. Model results indicated that the density of the two species was inversely related at the local scale, and complementary across the region; such that the density of one species increases from West to East while the other one declines. Overall, the comparison of density estimates between the two tortoises is consistent with a former hypothesis suggesting inter-specific competition and consequent resource partitioning. Other causes may contribute to explain the observed patterns, including the low productivity of rainforest habitats and long-term human perturbation.

  10. Determination of the water quality index ratings of water in the Mpumalanga and North West provinces, South Africa

    Science.gov (United States)

    Wanda, Elijah M. M.; Mamba, Bhekie B.; Msagati, Titus A. M.

    2016-04-01

    This study reports on the water quality index (WQI) of wastewater and drinking water in the Mpumalanga and North West provinces of South Africa. The WQI is one of the most effective tools available to water sustainability researchers, because it provides an easily intelligible ranking of water quality on a rating scale from 0 to 100, based on the ascription of different weightings to several different parameters. In this study the WQI index ratings of wastewater and drinking water samples were computed according to the levels of pH, electrical conductivity (EC), biochemical oxygen demand (BOD), E. coli, temperature, turbidity and nutrients (nitrogen and phosphates) found in water samples collected from the two provinces between June and December, 2014. This study isolated three groups of WQ-rated waters, namely: fair (with a WQI range = 32.87-38.54%), medium (with a WQI range = 56.54-69.77%) and good (with a WQI range = 71.69-81.63%). More specifically, 23%, 23% and 54% of the sampled sites registered waters with fair, medium and good WQ ratings respectively. None of the sites sampled during the entire period of the project registered excellent or very good water quality ratings, which would ordinarily indicate that no treatment is required to make it fit for human consumption. Nevertheless, the results obtained by the Eerstehoek and Schoemansville water treatment plants in Mpumalanga and North West provinces, respectively, suggest that substantial improvement in the quality of water samples is possible, since the WQI values for all of the treated samples were higher than those for raw water. Presence of high levels of BOD, low levels of dissolved oxygen (DO), E. coli, nitrates and phosphates especially in raw water samples greatly affected their overall WQ ratings. It is recommended that a point-of-use system should be introduced to treat water intended for domestic purposes in the clean-water-deprived areas.

  11. Ecological assessment of riparian forests in Benin

    NARCIS (Netherlands)

    Natta, A.K.

    2003-01-01

    The present research deals with the flora, phytosociology and ecology of riparian forests. The overall objective of this research is to contribute to a better knowledge of the flora, diversity and ecology of riparian forests inBenin

  12. Verbal art of the Fon (Benin)

    NARCIS (Netherlands)

    Aalders Grool, Marjolijn Cornelia

    2013-01-01

    This publication aims at the analysis of the performance of a corpus of Fongbe stories that I collected in three villages in the south of Benin in 1976 and 1977. The corpus consists of 37 stories (57.000 words). The stories aim at children’s education. Seven stories in my corpus are similar, althou

  13. Livelihood transitions and the changing nature of farmer-herder conflict in Sahelian West Africa.

    Science.gov (United States)

    Turner, Matthew D; Ayantunde, Augustine A; Patterson, Kristen P; Patterson III, E Daniel

    2011-01-01

    The accommodation of livestock husbandry with crop agriculture is crucial for the future of the West African Sahel. Present trends are leading to greater restrictions on livestock husbandry and a growing convergence of livelihood practices among groups whose identities are tied to herding and farming. Using the cases of four rural communities in Niger, this study adopts an 'access to resources' framework to analyse the causal connections among: rural peoples' livelihood strategies, everyday social relations of production, perceptions of social groups' identities, and the potential for farmer-herder conflict. While the convergence of livelihoods arguably increases the frequency of conflict triggers, it has also, through the expansion of shared common interests and cross-group, production-related relationships, improved the ability of communities to effectively manage these incipient conflicts. PMID:21495287

  14. Ethnic differences in use values and use patterns of Parkia biglobosa in Northern Benin

    OpenAIRE

    Koura Kourouma; Ganglo Jean C; Assogbadjo Achille E; Agbangla Clément

    2011-01-01

    Abstract Background African locust bean tree (Parkia biglobosa) is a multipurpose species used widely in arid Africa by local communities. The present study focused on ethnic differences in use values and use patterns of P. biglobosa in Northern Benin, where the species widely grows. The use values according to the various ethnic groups in the study area have been evaluated in detail for P. biglobosa. Methods From 13 ethnic groups, 1587 people were interviewed in the study area using semi-str...

  15. Pathology of fatal lineage 1 and 2 West Nile virus infections in horses in South Africa

    Directory of Open Access Journals (Sweden)

    June H. Williams

    2014-02-01

    Full Text Available Since 2007, West Nile virus (WNV has been reported in South African horses, causing severe neurological signs. All cases were of lineage 2, except for one case that clustered with lineage 1 viruses. In the present study, gross and microscopic lesions of six South African lineage 2-infected horses and the one lineage 1 case are described. Diagnoses were confirmed by real-time reverse-transcriptase polymerase chain reaction (RT-PCR of central nervous system (CNS tissue and one by RT-PCR of a brain virus isolate. The CNS of all cases was negative by RT-PCR or immunohistochemistry (IHC for African horse sickness (AHS, equine encephalosis virus, equine herpes viruses 1 and 4, other zoonotic flaviviruses, alphaviruses, and shunivirus, and either by immunofluorescence or IHC for rabies. Gross visceral lesions were nonspecific but often mimicked those of AHS. The CNS histopathology of WNV lineage 2 cases resembled the nonsuppurative polioencephalomyelitis reported in the Northern Hemisphere lineage 1 and recent Hungarian lineage 2 cases. Occasional meningitis, focal spinal ventral horn poliomalacia, dorsal and lateral horn poliomyelitis, leucomyelitis, asymmetrical ventral motor spinal neuritis and frequent olfactory region involvement were also seen. Lineage 2 cases displayed marked variations in CNS lesion severity, type and distribution, and suggested various viral entry routes into the CNS, based on findings in experimental mice and hamsters. Lineage 1 lesions were comparable to the milder lineage 2 cases. West Nile virus IHC on CNS sections with marked lesions from all cases elicited only two antigen-positive cells in the olfactory cortex of one case. The presence in the CNS of T-lymphocytes, B-lymphocytes, plasma cells and macrophage-monocytes was confirmed by cluster of differentiation (CD 3, CD20, multiple myeloma oncogene 1 (MUM1 and macrophage (MAC 387 IHC.

  16. Evaluation of Iron Toxicity on Lowland Irrigated Rice in West Africa

    Directory of Open Access Journals (Sweden)

    Chérif, M.

    2009-01-01

    Full Text Available In tropical areas, lowland rice (Oryza sativa L. cultivation (with or without irrigation is often hampered by iron toxicity. This edaphic stress is common in West African savanna and forest lowlands. It is a nutrient disorder associated with high iron concentrations in the soil solution. The reducing conditions of waterlogged lowland soils boost iron toxicity through solubilization of almost all iron in its ferrous form (Fe2+. This iron toxicity promoting edaphic features of lowland soils depends on the soil and climatic conditions, thus explaining the high spatiotemporal variability. The high quantity of ferrous ions in the soil solution upsets the mineral element balance in the rice and affects its growth. Ferrous iron (Fe2+ is abundantly taken up by the plant and becomes concentrated in the leaves, causing limb discoloration, reduced tillering, stunted growth, while substantially reducing yields. A survey was conducted to quantify the effects of iron toxicity on rice in three countries (Guinea, Ivory Coast and Ghana in the West African subregion. It was confirmed that iron toxicity is a major edaphic constraint in cultivated lowlands as it affects more than 50% of lowlands and about 60% of cultivated rice plots on average. About 10% of lowland crop fields were even abandoned due to high iron toxicity stress. Studies have also shown that more than 55% of rice-growing areas are affected by excess iron. There is also a significant impact on yield since affected plots were found to have a mean 54% lower yield as compared to healthy plots.

  17. Development of Reference Transcriptomes for the Major Field Insect Pests of Cowpea: A Toolbox for Insect Pest Management Approaches in West Africa

    OpenAIRE

    Tolulope A Agunbiade; Weilin Sun; Coates, Brad S; Rousseau Djouaka; Manuele Tamò; Ba, Malick N; Clementine Binso-Dabire; Ibrahim Baoua; Olds, Brett P; Pittendrigh, Barry R.

    2013-01-01

    Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrip...

  18. Pilanesberg National Park, North West Province, South Africa: Uniting economic development with ecological design – A history, 1960s to 1984

    OpenAIRE

    Jane Carruthers

    2011-01-01

    In the late 1970s, a ground-breaking project began in the Pilanesberg district in what is now the North West Province of South Africa to create a wildlife conservation and eco-tourism venture from degraded marginal farmland in an aesthetically attractive extinct volcanic crater. The establishment of this national park was innovative in a number of respects, including a partnership between landscape and ecological designers, local community development and participation, regional tourist ...

  19. Tourism SMME adoption of Information and Communication Technology in Ngaka Modiri Molema district of the North West province of South Africa / S.H. Phetlhe

    OpenAIRE

    Phetlhe, S H

    2011-01-01

    This paper reports on the investigation of ICT adoption of tourism SMMEs in Ngaka Modiri Molema District of the North West Province in South Africa. Self-administered questionnaires were distributed to 200 tourism enterprises with the response rate of 68%. The results indicate, that the level of adoption of ICT is highly influenced by the perception of ICT adoption of tourism SMMEs. Most of the tourism SMMEs use ICT for business purpose and factors such as size of enterprise...

  20. The availability of recreation policies and strategies for the provision of recreation service delivery in the North West Province, South Africa

    OpenAIRE

    Mogajane, V.S.; Meyer, C.; Monyeki, M.A.; Toriola, A. L.; Amusa, L.O.

    2014-01-01

    The promotion of recreation and leisure through coherent strategies and policy development is a significant move towards changing the quality lives of communities. The unavailability of recreation strategies and policies are associated with negative effect on the delivery of recreation services. The purpose of the study was therefore, to determine the availability of recreation strategies and policies in for the provision of recreation service delivery in North-West Province, South Africa. A ...