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During the past six years, ten research topics were carried out with the aim of developing an integrated method to improve production and sustainability of dairy systems in Cameroon. This involved reviewing dairy research done in ...
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During the past six years, ten research topics were carried out with the aim of developing an integrated method to improve production and sustainability of dairy systems in Cameroon. This involved reviewing dairy research done in the country, carrying out a participatory rural appraisal and an economic opportunity survey in selected dairy farms, setting up on-farm interventions, investigating cow reproduction, evaluating milk quality and the impact of integrated interventions. Guidelines for improvement of the dairy sector were set up. It was found that the developed integrated method had a positive impact on dairy farms. Farmers who adopted interventions had nearly 200% higher economic returns. In order to boost the Cameroonian dairy sector, it is suggested that the government acts as a motivating force by organizing the market, ensuring the monitoring of epizootic diseases and providing artificial insemination services and organizing breeding societies. It is also suggested that the integrated method becomes a discipline in dairy science and be applied in other developing countries.
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Groundwater is the only reliable water resource for drinking, domestic, and agricultural purposes for the people living in the Mount Cameroon area. Hydrogeochemical and R-mode factor analysis were used to identify hydrogeochemical...
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Groundwater is the only reliable water resource for drinking, domestic, and agricultural purposes for the people living in the Mount Cameroon area. Hydrogeochemical and R-mode factor analysis were used to identify hydrogeochemical processes controlling spring water quality and assess its usability for the above uses. Main water types in the study area are Ca-Mg-HCO_3 and Na-HCO_3. This study reveals that three processes are controlling the spring water quality. CC_2driven silicate weathering and reverse cation exchange are the most important processes affecting the hydrochemistry of the spring waters.While tropical oceanic monsoon chloride-rich/sulfate-rich rainwater seems to affect spring water chemistry at low-altitude areas, strong correlations exist between major ions, dissolved silica and the altitude of springs. In general, the spring waters are suitable for drinking and domestic uses. Total hardness (TH) values indicate a general softness of the waters, which is linked to the development of cardiovascular diseases. Based on Na %, residual sodium carbonate, sodium adsorption ratio, and the USSL classification, the spring waters are considered suitable for irrigation. Though there is wide spread use of chemical fertilizers and intense urban settlements at the lower flanks of the volcano, anthropogenic activities for now seem to have little impact on the spring water quality.
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Background: Malaria remains a major public health problem in Cameroon; however, despite reports on the adaptation of anopheline species to urban habitats, there is still not enough information on malaria transmission pattern in ur...
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Background: Malaria remains a major public health problem in Cameroon; however, despite reports on the adaptation of anopheline species to urban habitats, there is still not enough information on malaria transmission pattern in urban settings. In the frame of a larval control trial in the city of Yaoundé, we conducted baseline surveys to assess malaria transmission dynamics in this city. Methods: Adult mosquitoes were collected indoors and outdoors using CDC light traps and human landing catches from March 2017 to March 2018 in 30 districts of Yaoundé, Cameroon. Mosquitoes were sorted by genus and identified to the species level using PCR. The TaqMan method and ELISA were used to determine mosquito infection status to Plasmodium. Bioassays were conducted to assess female Anopheles gambiae susceptibility to insecticides. Results: A total of 218,991 mosquitoes were collected. The main malaria vectors were An. gambiae s.l. (n=6154) and An. funestus s.l. (n=229). Of the 1476 An. gambiae s.l. processed by PCR, 92.19% were An. coluzzii and 7.81% An. gambiae. An. funestus s.l. was composed of 93.01% (173/186) An. funestus and 4.84% (13/186) An. leesoni. The average biting rate of anopheline was significantly high outdoor than indoor (P=0.013). Seasonal variation in mosquito abundance and biting rate was recorded. The infection rate by Plasmodium falciparum was 2.13% (104/4893 mosquitoes processed). The annual entomological inoculation rate wasfound to vary from 0 to 92 infective bites/man/year (ib/m/y). Malaria transmission risk was high outdoor (66.65 ib/m/y) compared to indoor (31.14 ib/m/y). An. gambiae s.l. was found highly resistant to DDT, permethrin and deltamethrin. High prevalence of the West Africa kdr allele 1014F was recorded and this was not found to influence An. gambiae s.l. infection status. Conclusion: The study suggests high malaria transmission occurring in the city of Yaoundé and call for immediate actions to improve control strategies.
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The aim of the study was to determine the morphological and physicochemical characteristics, classification, genesis and suitability of soils developed on pediplain around granitic hills in Minawao in the Far North region of Camer...
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The aim of the study was to determine the morphological and physicochemical characteristics, classification, genesis and suitability of soils developed on pediplain around granitic hills in Minawao in the Far North region of Cameroon. The studied soil profile had 450 cm thick. It is composed of two subsections formed by erosion and cumulization. The upper subsection classified as typic ustifluvents clayey isohyperthermic is characterized by the high content of coarse elements showing stratifications in some part of the horizons. It recovers the below subsection classified as thapto typic haplustalfs clayey isohyperthermic. They are clayey, with clay contents ranging from 45 to 49%, and slightly acidic. Total nitrogen and organic carbon contents are very low ranging respectively from 0.05 to 0.11 and 0.25 to 0.63. Available phosphorous contents are below critical level. Calcium and Magnesium dominate the exchange complex of these soils. Their values range respectively from 12.96 to 15.04 cmol (+)/kg and 3.52 to 6.56 cmol (+)/kg. The CEC values are high, ranging from 44.64 to 57.84 cmol(+)/kg of soil. The CEC clay range from 89.92 to 117.02 cmol(+)/kg of clay. Base saturation percentage values are low, ranging from 37.05 to 42%, corresponding to a mean value of 39.74%. The studied soils are globally subjected to problems of low organic matter content, high coarse material content and low pH for the cultivation of Sorghum, Cotton, Soya, Groundnut, Maize and Cowpea. These problems could be solved through introduction of DMC systems, addition of available organic substrates, restoration of the cation balance and liming.
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An ethnobotanical survey was carried out in eight villages around Mount Cameroon in the South West Region of Cameroon. It was focused on determining the uses of the members of the family Annonaceae in this region. Show and Tell Se...
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An ethnobotanical survey was carried out in eight villages around Mount Cameroon in the South West Region of Cameroon. It was focused on determining the uses of the members of the family Annonaceae in this region. Show and Tell Semi-structured Interviews employing a checklist of questions and direct observations were used. The results obtained enable the presentation of the rate of utilization of the members of that family in the study area. At least 70% of the 41 species recorded during field trips from the research area were found to be widely used in traditional medicine by local populations. Some 29 diseases were cured using 24 species. The bark and the wood of these species were the most commonly used plant parts. The check list and ethnomedicinal inventory was developed alphabetically by botanical name, followed by local name, part used, ethnomedicinal uses, mode of usage and information on species availability. Plant specimens were collected, identified, preserved, mounted and voucher was deposited in the Limbe Botanic Garden (SCA) for future references.
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~(40)Ar/~(39)Ar ages of three basalt dykes that intrude the Precambrian basement in the southern continental part of the Cretaceous Cameroon Line are presented. Specimen were sampled at Dschang, Maham and Kendem (Cameroon). The ag...
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~(40)Ar/~(39)Ar ages of three basalt dykes that intrude the Precambrian basement in the southern continental part of the Cretaceous Cameroon Line are presented. Specimen were sampled at Dschang, Maham and Kendem (Cameroon). The ages obtained are 421.3 ± 3.5 Ma (Dschang), 404.22 ± 3.51 Ma (Maham), and 192.10 ± 7.45 Ma (Kendem). The Dschang and Maham samples yield a relatively undisturbed spectrum while the Kendem sample shows an excess of argon but with plateau ages in the frame of the Mesozoic. Plateau ages at Dschang, Maham and Kendem represent more than 80% of the total ~(39)Ar released and are interpreted as emplacement ages. ~(40)Ar/~(39)Ar dating results confirm Devonian and Jurassic K/Ar ages obtained from similar dykes of the same region. Geochemically, the basalt dykes are subalkaline in composition with 45-50 wt.% SiO_2. Incompatible trace elements and rare earth elements are lower than that of the Cameroon Line basalts. Overall geochemical characteristics of the basalt dykes much more closely resemble those of tholeiites of the Benue Through in Nigeria that are interpreted as related to the opening of the Atlantic Ocean. The combination of ~(40)Ar/~(39)Ar ages, major, trace and rare earth elements geochemistry data demonstrate a magmatic phase that is significantly older and different of that of the Cretaceous Cameroon Line and younger than the dominantly granitic Neoproterozoic to early Paleozoic magmatism in the region. These findings offer new clues for a better understanding of the tectonic history of the region, particularly the origin of the Cameroon Line and Africa-South America pre-drift reconstitutions.
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A growing body of literature shows that social media plays a key role during crises and conflicts. In addition to traditional media, social media are used to mobilise people for a common cause and to communicate vital information....
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A growing body of literature shows that social media plays a key role during crises and conflicts. In addition to traditional media, social media are used to mobilise people for a common cause and to communicate vital information. Very little is known about social media use during crises in the sub-Saharan African context. This article presents how Twitter is being used in the ongoing Cameroon Anglophone Crisis by several groups including the government, Anglophone activists, media organisations, and everyday citizens. Using critical theoretical perspectives to examine tweets from 1 September 2016 to 31 December 2018, this article identifies key themes. These include: placement of the crisis in a contested, historical context; debates about naming the crisis; key concepts; depiction of several forms of violence; and potential options for resolution. Social media is being used by the government, Anglophone activists, and non-affiliated people to sway public opinions on the crisis and solicit the attention of local, Diaspora, and broader international communities. Social media use has loosened the grip of governmental control of media messaging and expanded the public narratives available in Cameroon, yet at the time of the writing, this does not appear to have lessened the impact of the crisis.
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The Cretaceous basins of the West and Central African Rift System (WCARS) are characterized by sinistral strike–slip movements observed between the Benue and Arabian–Nubian microplates. These basins share a similar basin‐fillin...
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The Cretaceous basins of the West and Central African Rift System (WCARS) are characterized by sinistral strike–slip movements observed between the Benue and Arabian–Nubian microplates. These basins share a similar basin‐filling structure, history, and tectonic processes. They have attracted a significant interest in the study of their geodynamics and subsurface structure through geophysical exploration methods. Nevertheless, North Cameroon located in this microplate confluence has not yet been investigated in terms of identifying geological structures, such as lineaments and faults. To contribute to a better understanding of the northern Cameroon structural framework and its tectonic context, we investigate the lineaments in northern Cameroon by using the EIGEN‐6C4 gravitational model and a variety of recent processing techniques (Tilt derivative [TDR], Theta Map [TM], Horizontal tilt angle [TDX], and Edge Detector [ED]). Our results show that the lineaments are trending in ENE–WSW, NW–SE, NE–SW, and WNW–ESE directions. These directions are consistent with the Cretaceous Garoua Rift and granitoids of the Cameroon‐Chad line. The presented result clearly delineates continuous architectonic features of the structural edges of the Saharan Metacraton, the Cretaceous Garoua Rift, the Bibemi‐Léré granitoids, and the Adamawa faults.
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The EGOV.CM programme, led by the National Agency for ICT (ANTIC) aims to promote access to government information and services, provide IT support to the public administration reform programme, promote the objectives of national ...
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The EGOV.CM programme, led by the National Agency for ICT (ANTIC) aims to promote access to government information and services, provide IT support to the public administration reform programme, promote the objectives of national policies and provide an appropriate legal and regulatory environment. However, government and citizen reliance on ICTs presents a security challenge, given the emergence of cybercrime across the globe. This requires changes to legislation drafted before the electronic age. Outdated laws result in impunity, with the country a safe haven for cybercriminals, while e-government transactions may be unprotected and may therefore be discouraged. Cameroon's e-laws of 2010 (cybersecurity and electronic communications) provide a legal framework for the protection of ICT networks and critical infrastructures, creating an enabling environment for e-government services. These research notes highlight the importance of the e-laws for effective Cameroonian public administration, and discuss the challenges for implementation of e-government.
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In the western Cameroon, crop out several dyke swarms of Paleozoic–Mesozoic age. These dykes intrude the Precambrian basement in the southern continental part of the Cretaceous Cameroon Volcanic Line. In the Njimom area, two grou...
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In the western Cameroon, crop out several dyke swarms of Paleozoic–Mesozoic age. These dykes intrude the Precambrian basement in the southern continental part of the Cretaceous Cameroon Volcanic Line. In the Njimom area, two groups of mafic dykes that crosscut the Neoproterozoic basement rocks have been observed. A first group intrudes the mylonites whereas the second group intrudes the granites. The dykes are alkaline basalts and hawaiites. The mineralogical assemblage of both groups of dykes consists of plagioclase, clinopyroxene, altered olivine, and opaque oxides. The dykes that cross-cut the Precambrian mylonitic gneisses show moderate TiO2 (1.7–2.0 wt.%), low MgO (4.4–7.1 wt.%), and compatible trace element concentrations (e.g., Cr = 70–180 ppm; Ni = 30–110 ppm). The dykes that intrude the granites have TiO2 contents between 2.3 and 2.5 wt.% and moderate compatible trace element concentrations (e.g., Cr = 260–280 ppm; Ni = 170–230 ppm). MgO varies from 5.9 to 9.2 wt.%. All mafic dykes are enriched in light lanthanide element and show moderate Zr/Nb and high Zr/Y, Nb/Yb, and Ti/V ratios similar to those of average ocean island basalt (OIB)-type magmas. Some dykes that intrude the mylonites show evidence of contamination by continental crust. The composition of the clinopyroxenes of the dykes that intrude the mylonites clearly indicate different and unrelated parental magmas from dykes that intrude the granites. Contents and fractionation of the least and the most incompatible elements suggest low degrees of partial melting (3–5%) of heterogeneous source slightly enriched in incompatible elements in the spinel stability field. The geochemical features of Njimom dykes (in particular the dykes that intrude the granites) are similar to those of Paleozoic and Mesozoic dykes recorded in the southern continental part of the Cameroon Volcanic Line, suggesting multiple reactivations of pre-existing fractures that resulted in the fragmentation of western Gondwana and the opening of the South Atlantic Ocean.
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