Science.gov

Sample records for malawi southern africa

  1. Groundwater supply and demand from southern Africa's crystalline basement aquifer: evidence from Malawi

    NASA Astrophysics Data System (ADS)

    Robins, Nick; Davies, Jeffrey; Farr, John

    2013-06-01

    Failure of borehole sources in weathered and fractured crystalline basement aquifers in Malawi in southern Africa has been linked with poor borehole design, mechanical failure and badly sited boreholes. However, recent work in Malawi indicates that demand may now exceed long-term resource potential in some places and that this is also a cause of water point failure. An 11-year climate cycle (including a wet and dry period) necessitates overdraft from groundwater storage during the dry-cycle years before episodic rainfall events in the wetter part of the cycle again recharge the aquifers. Data, particularly groundwater hydrograph data, are sparse, but sufficient to evaluate the long-term renewable groundwater potential for both fractured and weathered basement-aquifer types in each of the 15 management areas in Malawi. The groundwater potential or long-term renewable resource (recharge) is given by the sum of Darcian throughflow and dry-season depletion of storage. Estimated rural demand exceeds the renewable resource in the fractured-rock aquifer in two management units and in the weathered-rock aquifer in two other units. Although there is inherent uncertainty in the water-balance estimates, the likelihood that rural demand is exceeding long-term average recharge in some areas is cause for concern.

  2. Discipline in the Context of Development: A Case of the Social Sciences in Malawi, Southern Africa

    ERIC Educational Resources Information Center

    Holland, Dana G.

    2008-01-01

    Changes in research production precipitated by the globalization have generally been theorized as applying across nations and disciplinary projects. This article examines the relation of discipline to research production from the situational vantage point of the developing world, specifically the Southern African country of Malawi, and from the…

  3. Barriers to Uptake of Conservation Agriculture in southern Africa: Multi-level Analyses from Malawi

    NASA Astrophysics Data System (ADS)

    Dougill, Andrew; Stringer, Lindsay; Whitfield, Stephen; Wood, Ben; Chinseu, Edna

    2015-04-01

    Conservation agriculture is a key set of actions within the growing body of climate-smart agriculture activities being advocated and rolled out across much of the developing world. Conservation agriculture has purported benefits for environmental quality, food security and the sustained delivery of ecosystem services. In this paper, new multi-level analyses are presented, assessing the current barriers to adoption of conservation agriculture practices in Malawi. Despite significant donor initiatives that have targeted conservation agriculture projects, uptake rates remain low. This paper synthesises studies from across 3 levels in Malawi: i.) national level- drawing on policy analysis, interviews and a multi-stakeholder workshop; ii.) district level - via assessments of development plans and District Office and extension service support, and; iii) local level - through data gained during community / household level studies in Dedza District that have gained significant donor support for conservation agriculture as a component of climate smart agriculture initiatives. The national level multi-stakeholder Conservation Agriculture workshop identified three areas requiring collaborative research and outlined routes for the empowerment of the National Conservation Agriculture Task Force to advance uptake of conservation agriculture and deliver associated benefits in terms of agricultural development, climate adaptation and mitigation. District level analyses highlight that whilst District Development Plans are now checked against climate change adaptation and mitigation criteria, capacity and knowledge limitations exist at the District level, preventing project interventions from being successfully up-scaled. Community level assessments highlight the need for increased community participation at the project-design phase and identify a pressing requirement for conservation agriculture planning processes (in particular those driven by investments in climate

  4. Southern Africa

    Atmospheric Science Data Center

    2013-04-16

    article title:  Southern Africa     View larger JPEG image ... These Multi-angle Imaging SpectroRadiometer (MISR) images of Africa were acquired on August 25, 2000, during Terra orbit 3655. The left ... of smoke plumes and haze. The southern tip of South Africa is at the bottom of the image, and Zambia is at the top. Distinctive ...

  5. Typhoid fever and invasive nontyphoid salmonellosis, Malawi and South Africa.

    PubMed

    Feasey, Nicholas A; Archer, Brett N; Heyderman, Robert S; Sooka, Arvinda; Dennis, Brigitte; Gordon, Melita A; Keddy, Karen H

    2010-09-01

    To determine the prevalence of invasive nontyphoid salmonellosis and typhoid fever in Malawi and South Africa, we compared case frequency and patient age distribution. Invasive nontyphoid salmonellosis showed a clear bimodal age distribution; the infection developed in women at a younger age than in men. Case frequency for typhoid fever was lower than for salmonellosis. PMID:20735930

  6. Typhoid Fever and Invasive Nontyphoid Salmonellosis, Malawi and South Africa

    PubMed Central

    Feasey, Nicholas A.; Archer, Brett N.; Heyderman, Robert S.; Sooka, Arvinda; Dennis, Brigitte; Keddy, Karen H.

    2010-01-01

    To determine the prevalence of invasive nontyphoid salmonellosis and typhoid fever in Malawi and South Africa, we compared case frequency and patient age distribution. Invasive nontyphoid salmonellosis showed a clear bimodal age distribution; the infection developed in women at a younger age than in men. Case frequency for typhoid fever was lower than for salmonellosis. PMID:20735930

  7. Risk Communication of Groundwater Quality in Northern Malawi, Africa

    NASA Astrophysics Data System (ADS)

    Holm, R.

    2011-12-01

    Malawi lies in Africa's Great Rift Valley. Its western border is defined by Lake Malawi, the third largest lake in Africa. Over 80% of Malawians live in rural areas and 90% of the labor force is associated with agriculture. More than half of the population lives below the poverty line. Area characteristics indicate a high likelihood of nitrate and total coliform in community drinking water. Infants exposed to high nitrate are at risk of developing methemoglobinemia. In addition, diarrheal diseases from unsafe drinking water are one of the top causes of mortality in children under five. Without sufficient and sustainable supplies of clean water, these challenges will continue to threaten Malawi's ability to overcome the devastating impact of diarrheal diseases on its population. Therefore, Malawi remains highly dependent on outside assistance and influence to reduce or eliminate the threat posed by unsafe drinking water. This research presents a literature review of nitrate and total coliform groundwater quality and a proposed risk communication plan for drinking water in northern Malawi.

  8. Headteacher Preparation in Mzuzu, Malawi, Africa

    ERIC Educational Resources Information Center

    Wamba, Nathalis

    2015-01-01

    The purpose of this researcher was to examine the in-service experiences of seven headteachers in Luwinga ward in Mzuzu, Malawi, and the challenges they encountered in their first year on the job. A modified version of the questionnaire and interview guide developed by the members of the International Study of the Preparation of Principals at the…

  9. Crustal Structure in Northern Malawi and Southern Tanzania surrounding Lake Malawi and the Rungwe Volcanic Province

    NASA Astrophysics Data System (ADS)

    Borrego, D.; Kachingwe, M.; Nyblade, A.; Shillington, D. J.; Gaherty, J. B.; Ebinger, C. J.; Accardo, N. J.; O'Donnell, J. P.; Mbogoni, G. J.; Mulibo, G. D.; Chindandali, P. R. N.; Mphepo, F.; Ferdinand-Wambura, R.; Tepp, G.

    2015-12-01

    Crustal Structure in Northern Malawi and Southern Tanzania surrounding Lake Malawi and the Rungwe Volcanic Province David Borrego, Marsella Kachingwe, Andrew Nyblade, Donna Shillington, James Gaherty, Cynthia Ebinger, Natalie Accardo, J.P. O'Donnell, Gabriel Mbogoni, Gabriel Mulibo, Richard Ferdinand, Patrick Chindandali, Felix Mphepo, Gabrielle Tepp, Godson Kamihanda We investigate crustal structure around the northern end of Lake Malawi and in the Rungwe Volcanic Province using teleseismic receiver functions from the SEGMeNT broadband seismic network. The SEGMeNT network includes 55 broadband stations deployed in northern Malawi and southern Tanzania, with station spacing of 20-50 km. Fourteen stations were deployed in August 2013, and an additional of 41 stations were added to the study region beginning June/July 2014. Fifteen stations are located in Malawi and 40 stations in Tanzania. Data from teleseismic earthquakes with magnitude 5.5 or greater in the 30 to 90 degrees distance range have been used to calculate P-wave receiver functions. Estimates of Moho depth and Vp/Vs ratios have been obtained by using the H-k stacking method and by jointly inverting the receiver functions with Rayleigh wave phase velocities. Preliminary results show an average Moho depth of 40 km and an average Vp/Vs ratio of 1.72. Little evidence is found for magmatic underplating beneath the Rungwe Volcanic Province.

  10. Literacy for Revitalization in the SADCC Countries of Southern Africa.

    ERIC Educational Resources Information Center

    Bhola, H. S.

    The role of literacy in the revitalization of societies is particularly meaningful in the context of the Southern African Development Coordination Conference (SADCC), a group of nine countries (Angola, Botswana, Lesotho, Malawi, Mozambique, Swaziland, Tanzania, Zambia, and Zimbabwe) surrounding or surrounded by the Republic of South Africa (RSA).…

  11. Barriers to pilot mobile teleophthalmology in a rural hospital in Southern Malawi

    PubMed Central

    Pérez, Guillermo Martínez; Swart, Wayne; Munyenyembe, Jimmy Kondwani; Saranchuk, Peter

    2014-01-01

    Introduction Malawi has one of the highest HIV prevalences in Sub-Saharan Africa. The rate of eligible HIV-infected people being initiated on antiretroviral therapy (ART) and retained in HIV-care is currently far from adequate. Consequently, many people continue present with advanced immunosuppression at public health facilities, often with undiagnosed opportunistic infections (OIs). Methods In this context, mHealth was the innovation chosen to assist Eye Clinical Officers in early diagnosis of HIV-related diseases having eye manifestations in a rural hospital in Thyolo, Southern Malawi. Results The mTeleophthalmology program began in October 2013, but was stopped prematurely due to organizational and technological barriers that compromised its feasibility. Conclusion Sharing these barriers might be useful to inform the design of similar innovations in other resource-limited settings with a high HIV prevalence and a dearth of eye specialists with capacity to diagnose HIV-related retinopathies. PMID:25767656

  12. Smoke in Southern Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This SeaWiFS true-color image acquired over Southern Africa on Sept. 4, 2000, shows a thick shroud of smoke and haze blanketing much of the southern half of the continent. The smoke in this scene is being generated by a tremendous number of fires burning over a large area across the countries of Angola, Zambia, Mozambique, Zimbabwe, Botswana, and the Northern Province of South Africa. In this image, the smoke (grey pixels) is easily distinguished from clouds (bright white pixels). Refer to the Images and Data section for a larger scale view of the fires in Southern Africa. Data from both the SeaWiFS and Terra satellites are being used by an international team of scientists participating in the SAFARI field experiment. The objective of SAFARI is to measure the effects of windblown smoke and dust on air quality and the Earth's radiant energy budget. This image was produced using SeaWiFS channels 6, 5, and 1 (centered at 670 nm, 555 nm , and 412 nm, respectively). The data were acquired and provided by the Satellite Applications Center in Pretoria, South Africa. Image courtesy Gene Feldman, SeaWiFS Project and Orbital Sciences

  13. Energy resources in southern Africa: a select bibliography

    SciTech Connect

    Cavan, A.

    1981-01-01

    The aims, progress, and possibilities involved in Southern Africa's energy development are the subject of this 473-item bibliography. The primary items of information described in this document are relatively recent (1975-81), originate from both indigenous and international sources, and are mostly in English, although a few are in French and Portuguese. The presented information focuses on the African continent, the Southern African region, and the nations of Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, Swaziland, South Africa, Tanzania, Zambia, and Zimbabwe. The energy source topics include alcohol, coal, gas, oil, solar, uranium, water, wind, and wood; as well as a general energy-development category.

  14. Astrophysics in Southern Africa

    NASA Astrophysics Data System (ADS)

    Whitelock, Patricia

    2008-03-01

    The government of South Africa has identified astronomy as a field in which their country has a strategic advantage and is consequently investing very significantly in astronomical infrastructure. South Africa now operates a 10-m class optical telescope, the Southern African Large Telescope (SALT), and is one of two countries short listed to host the Square Kilometre Array (SKA), an ambitious international project to construct a radio telescope with a sensitivity one hundred times that of any existing telescope. The challenge now is to produce an indigenous community of users for these facilities, particularly from among the black population which was severely disadvantaged under the apartheid regime. In this paper I briefly describe the observing facilities in Southern Africa before going on to discuss the various collaborations that are allowing us to use astronomy as a tool for development, and at the same time to train a new generation of astronomers who will be well grounded in the science and linked to their colleagues internationally.

  15. Sex, money, and premarital partnerships in southern Malawi.

    PubMed

    Poulin, Michelle

    2007-12-01

    In this paper, I argue two main points. First, in premarital, sexual partnerships in rural Malawi, the purpose of money exchange extends beyond the alleviation of female partners' economic constraints, and, second, by clarifying this broader purpose, it becomes possible to recognize where women exert control over their own sexual selves. These findings come from field observations and a rich set of in-depth interviews (N=54), bolstered on occasion by survey data, conducted with young women and men, aged 15-24 years, in the Balaka district in the southern region of the country. This research demonstrates that, contrary to typical expectations, money and gift transfers in sexual partnerships are part and parcel of the courting practices of young Malawian women and men. Transfers are as much about the expression of love and commitment as they are about meeting the financial needs of women or the acquisition of sex for men. Using narrative information to shed light on the semiotics of the sex-money link, these findings from Malawi offer a new perspective that broadens usual interpretations of transactional sex, the understanding of which is critical in fighting AIDS. PMID:17764797

  16. Sex, Money, and Premarital Relationships in Southern Malawi

    PubMed Central

    Poulin, Miss Michelle J.

    2009-01-01

    In this paper, I argue two main points: (1), the purpose of money exchange in premarital, sexual partnerships in rural Malawi extends beyond the alleviation of female partners’ economic constraints, and (2), by elucidating this broader purpose, it becomes possible to recognize where women exert control over their own sexual selves. These findings come from field observations and a rich set of in-depth interviews (N=54), bolstered on occasion by survey data, conducted with young women and men, aged 15 to 24 years, in the Balaka district in the southern region of the country. My research demonstrates that, contrary to typical expectations, money and gift transfers in sexual partnerships are part and parcel of the courting practices of young Malawian women and men. Transfers are as much about the expression of love and commitment as they are about meeting the financial “needs” of women or the acquisition of sex for men. Using narrative information to shed light on the semiotics of the sex-money link, these findings from Malawi offer a new perspective that broadens usual interpretations of “transactional” sex, the understanding of which is critical in fighting AIDS. PMID:17764797

  17. A ~1.3Ma paleoecological record from scientific drilling at Lake Malawi, East Africa

    NASA Astrophysics Data System (ADS)

    Cohen, Andrew S.; Blome, Margaret; Ivory, Sarah; King, John; Cole, Julie; McGlue, Michael

    2016-04-01

    Long records of Quaternary ecological and climatic change are critical to understanding the range of potential responses of ecosystems to environmental forcing. Here we present an integrated lake and watershed paleoecological analysis from drill core records obtained by the Lake Malawi Drilling Project, documenting extraordinary fluctuations in climate, hydrology and ecosystem response for the southern tropics of Africa. High resolution lacustrine and terrestrial paleoecology and sedimentology data sets from these Early Pleistocene-Holocene drill cores provide the most complete record of this duration currently available from Africa. Time series analyses of these records demonstrate strong orbital forcing of regional hydroclimate that drives high-amplitude changes in Malawi ecosystems. Prior to ~600ka we also observe a secondary overprint of watershed processes involving river capture or diversion that may have a tectonic origin. We observe shifts between more arid conditions (shallow alkaline and well mixed lake, with discontinuous desert vegetation) and more humid environments (deep, stratified, freshwater lake with dense forest). These broadly synchronous changes in lake paleoecology, lake sedimentology, and watershed vegetation demonstrate the major role of climate in regulating this system. Transitions between these lake/watershed state extremes is often very abrupt, suggesting that the combined lake/watershed repeatedly passed through hydroclimate thresholds, with important implications for the evolution of the lake's endemic biodiversity and ecosystem. The tempo of lake/watershed state fluctuations changes at the Mid-Pleistocene Transition, altering from one of higher frequency/lower amplitude variability prior to 900ka to lower frequency/higher amplitude variability after that time.

  18. Assessment of groundwater quality in shallow wells within the southern districts of Malawi

    NASA Astrophysics Data System (ADS)

    Pritchard, M.; Mkandawire, T.; O'Neill, J. G.

    Lack of safe drinking water is a major problem in developing countries. Within Africa most people rely mainly on local groundwater sources for their water needs. These can be deep boreholes or shallow wells, the latter are normally found in poorer communities as they are the least expensive to construct. Over time water from these sources can be contaminated leading to fatal consequences. Previous monitoring of the quality of water from boreholes and shallow wells have been irregular, with the focus being mainly on boreholes. Information on seasonal water quality changes in shallow wells used by rural communities in Malawi has generally been lacking. A study was conducted from 2006 to 2007 to determine the quality of water from shallow wells in three districts in southern Malawi namely, Balaka, Chikwawa and Zomba districts. Water samples from 21 covered and five open shallow wells were analysed for chemical, microbiological and physical parameters using a portable water testing kit. Sampling was carried out at four different times of the year i.e. in August and October 2006 (dry season) and February and April 2007 (wet season). Microbiological data indicated that around 80% of the samples, obtained from the covered wells, failed to meet safe drinking water limits, set by World Health Organisation guidelines and Malawi Bureau of Standards, of zero total and faecal colony forming units (cfu)/100 ml. Values in excess of 1000 cfu/100 ml were noted in 10% of the samples, indicating gross contamination and the probability of pathogens being present. Contamination levels were higher during the wet season than the dry season in all three districts. Arsenic, ammonia, nitrate, nitrite and sulphate were all within the acceptable limits. Elevated levels of hardness, turbidity were noted in certain wells.

  19. Universal Basic Education and the Provision of Quality Mathematics in Southern Africa

    ERIC Educational Resources Information Center

    Kazima, Mercy

    2014-01-01

    In this paper, I discuss Universal Basic Education (UBE) in relation to the teaching and learning of mathematics in Southern Africa. I present the status of UBE for all countries in the region and then use 3 selected examples: Botswana, Malawi, and Zambia, to illustrate the provision of mathematics in the general framework of UBE in the countries.…

  20. Central and southern Africa

    SciTech Connect

    McGrew, H.J.

    1981-10-01

    Exploration in central and southern Africa continued to expand during 1980. The greatest concentration of activity was in Nigeria. However, there was considerable increase in the level of exploratory work in Cameroon and Congo. Significant new finds have been made in Ivory Coast. Geological and geophysical activity was carried out in 18 of the countries, with those in the western part having the largest share. Seismic work involved 225 party months of operation. Most of this time was spent on land, but marine operations accounted for 73,389 km of new control. Gravity and magnetic data were recorded during the marine surveys, and several large aeromagnetic projects were undertaken to obtain a total of 164,498 line km of data. Exploratory and development drilling accounted for a total of 304 wells and 2,605,044 ft (794,212 m) of hole. The 92 exploratory wells that were drilled resulted in 47 oil and gas discoveries. In development drilling 89% of the 212 wells were successful. At the end of the year, 27 exploratory wells were underway, and 34 development wells were being drilled for a total of 61. Oil production from the countries that this review covers was 918,747,009 bbl in 1980, a drop of about 9% from the previous year. Countries showing a decline in production were Nigeria, Gabon, Cabinda, and Zaire. Increases were recorded in Cameroon, Congo, and Ghana. A new country was added to the list of producers when production from the Belier field in Ivory Coast came on stream. 33 figures, 15 tables.

  1. Adaptive strategies to climate change in Southern Malawi

    NASA Astrophysics Data System (ADS)

    Chidanti-Malunga, J.

    Climate change poses a big challenge to rural livelihoods in the Shire Valley area of Southern Malawi, where communities have depended almost entirely on rain-fed agriculture for generations. The Shire Valley area comprises of low-altitude dambo areas and uplands which have been the main agricultural areas. Since early to mid 1980s, the uplands have experienced prolonged droughts and poor rainfall distribution, while the dambos have experienced recurrent seasonal floods. This study assessed some of the adaptive strategies exercised by small-scale rural farmers in response to climate change in the Shire Valley. The methodology used in collecting information includes group discussions, household surveys in the area, secondary data, and field observations. The results show that small-scale rural farmers exercise a number of adaptive strategies in response to climate change. These adaptive strategies include: increased use of water resources for small-scale irrigation or wetland farming, mostly using simple delivery techniques; increased management of residual moisture; and increased alternative sources of income such as fishing and crop diversity. It was also observed that government promoted the use of portable motorized pumps for small-scale irrigation in order to mitigate the effects of climate change. However, these external interventions were not fully adopted; instead the farmers preferred local interventions which mostly had indigenous elements.

  2. The High Burden of Malaria in Primary School Children in Southern Malawi

    PubMed Central

    Mathanga, Don P.; Halliday, Katherine E.; Jawati, Mpumulo; Verney, Allison; Bauleni, Andrew; Sande, John; Ali, Doreen; Jones, Rebecca; Witek-McManus, Stefan; Roschnik, Natalie; Brooker, Simon J.

    2015-01-01

    Malaria among school children has received increased attention recently, yet there remain few detailed data on the health and educational burden of malaria, especially in southern Africa. This paper reports a survey among school children in 50 schools in Zomba District, Malawi. Children were assessed for Plasmodium infection, anemia, and nutritional status and took a battery of age-appropriate tests of attention, literacy, and numeracy. Overall, 60.0% of children were infected with Plasmodium falciparum, 32.4% were anemic and 32.4% reported sleeping under a mosquito net the previous night. Patterns of P. falciparum infection and anemia varied markedly by school. In multivariable analysis, higher odds of P. falciparum infection were associated with younger age and being stunted, whereas lower odds were associated with reported net use, higher parental education, and socioeconomic status. The odds of anemia were significantly associated with P. falciparum infection, with a dose–response relationship between density of infection and odds of anemia. No clear relationship was observed between health status and cognitive and educational outcomes. The high burden of malaria highlights the need to tackle malaria among school children. PMID:26283750

  3. The High Burden of Malaria in Primary School Children in Southern Malawi.

    PubMed

    Mathanga, Don P; Halliday, Katherine E; Jawati, Mpumulo; Verney, Allison; Bauleni, Andrew; Sande, John; Ali, Doreen; Jones, Rebecca; Witek-McManus, Stefan; Roschnik, Natalie; Brooker, Simon J

    2015-10-01

    Malaria among school children has received increased attention recently, yet there remain few detailed data on the health and educational burden of malaria, especially in southern Africa. This paper reports a survey among school children in 50 schools in Zomba District, Malawi. Children were assessed for Plasmodium infection, anemia, and nutritional status and took a battery of age-appropriate tests of attention, literacy, and numeracy. Overall, 60.0% of children were infected with Plasmodium falciparum, 32.4% were anemic and 32.4% reported sleeping under a mosquito net the previous night. Patterns of P. falciparum infection and anemia varied markedly by school. In multivariable analysis, higher odds of P. falciparum infection were associated with younger age and being stunted, whereas lower odds were associated with reported net use, higher parental education, and socioeconomic status. The odds of anemia were significantly associated with P. falciparum infection, with a dose-response relationship between density of infection and odds of anemia. No clear relationship was observed between health status and cognitive and educational outcomes. The high burden of malaria highlights the need to tackle malaria among school children. PMID:26283750

  4. Atmospheric chemistry over southern Africa

    NASA Astrophysics Data System (ADS)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2012-03-01

    Changing Chemistry in a Changing Climate: Human and Natural Impacts Over Southern Africa (C4-SAR); Midrand, South Africa, 31 May to 3 June 2011 During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semipermanent atmospheric gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite- derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission on Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from Eskom, the South African power utility; and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa.

  5. Cyclists' helmet usage and characteristics in central and southern Malawi: a cross-sectional study.

    PubMed

    Kraemer, John D; Honermann, Brian J; Roffenbender, Jason S

    2012-01-01

    The objective of this study was to determine the prevalence of, and factors associated with, bicycle helmet usage in southern and central Malawi. This study was across-sectional observation of public behaviour. The urban and rural roadways in southern and central Malawi were studied during the dry season. In total, 1900 bicyclists were observed along the roadways of southern and central Malawi over a four-day period. Observer ascertainment of cyclists' helmet status, approximate age, sex and bicycle operator or passenger status were measured. Of the 1900 cyclists observed, no cyclist was identified as wearing a helmet (exact 95% CI: 0.0-0.2%). There was no variation by age, sex or operator/passenger status. Nearly, 91.5% of observed cyclists were males and 87.7% were operating the bicycle. The sizeable majority of male cyclists were classified as young adults from adolescence to 25 years old (47.2%) or adults over age 25 (44.9%); 7.9% of male cyclists were pre-adolescent. Passengers were more likely to be female than operators (39.1% versus 4.2%), though, even for passengers, a higher proportion were males than females (p < 0.001). In Malawi, helmet usage is so rare as to be non-existent. This suggests an opportunity for significant improvement. Based on the observed cyclists' characteristics, interventions should be targeted to adult and young adult males. PMID:22394127

  6. Atmospheric Chemistry Over Southern Africa

    NASA Technical Reports Server (NTRS)

    Gatebe, Charles K.; Levy, Robert C.; Thompson, Anne M.

    2011-01-01

    During the southern African dry season, regional haze from mixed industrial pollution, biomass burning aerosol and gases from domestic and grassland fires, and biogenic sources from plants and soils is worsened by a semi-permanent atmosphere gyre over the subcontinent. These factors were a driver of several major international field campaigns in the 1990s and early 2000s, and attracted many scientists to the region. Some researchers were interested in understanding fundamental processes governing chemistry of the atmosphere and interaction with climate change. Others found favorable conditions for evaluating satellite-derived measurements of atmospheric properties and a changing land surface. With that background in mind a workshop on atmospheric chemistry was held in South Africa. Sponsored by the International Commission for Atmospheric Chemistry and Global Pollution (ICACGP; http://www.icacgp.org/), the workshop received generous support from the South African power utility, Eskom, and the Climatology Research Group of the University of the Witwatersrand, Johannesburg, South Africa. The purpose of the workshop was to review some earlier findings as well as more recent findings on southern African climate vulnerability, chemical changes due to urbanization, land-use modification, and how these factors interact. Originally proposed by John Burrows, president of ICACGP, the workshop was the first ICACGP regional workshop to study the interaction of air pollution with global chemical and climate change. Organized locally by the University of the Witwatersrand, the workshop attracted more than 60 delegates from South Africa, Mozambique, Botswana, Zimbabwe, France, Germany, Canada, and the United States. More than 30 presentations were given, exploring both retrospective and prospective aspects of the science. In several talks, attention was focused on southern African chemistry, atmospheric pollution monitoring, and climate processes as they were studied in the field

  7. Sedimentary deposits in response to rift geometry in Malawi, Africa

    SciTech Connect

    Bishop, M.G. )

    1991-03-01

    Sedimentary deposits of the Malawi continental rift basin are a direct result of topography and tectonics unique to rift structure. Recent models describe rifts as asymmetric half-graben connected in series by transfer of accommodation zones. Half-graben consist of roughly parallel, tilted fault blocks stepping up from the bounding fault zone where maximum subsidence occurs. The rift becomes a local baselevel and depocenter as regional drainage is shed away by the rift shoulders. Most of the sediments are derived locally due to internal drainage of connected basins, individual basins, and individual fault blocks. The patterns of sedimentation and facies associations depend on structural position at both fault block and half-graben scales. Drainage is directed and dammed by tilted fault blocks. Forward-tilted fault blocks form basinward-thickening sediment wedges filled with facies of axial fluvial systems, alluvial fault-scarp fans, and ponded swamp and lake deposits. These deposits are asymmetrically shifted toward the controlling fault and onlap the upthrown side of the block, ordinarily the site of erosion or nondeposition. Rivers entering the lake on back tilted fault blocks form large deltas resulting in basinward fining and thinning sediment wedges. Lacustrine, nearshore, shoreline, and lake shore plain deposits over multiple fault blocks record lake levels, water chemistry, and tectonic episodes. Tectonic movement periodically changes the basin depth, configuration, and baselevel. This movement results in widespread unconformities deposition and reworking of sediments within the rift.

  8. ARE LITERACY SKILLS ASSOCIATED WITH YOUNG ADULTS’ HEALTH IN AFRICA? EVIDENCE FROM MALAWI

    PubMed Central

    Smith-Greenaway, Emily

    2014-01-01

    This study investigates whether literacy skills are a distinct dimension of education that influences young adults’ health in the southeast African context of Malawi. It uses new data from Tsogolo la Thanzi, a study of young adults in southern Malawi, to achieve three aims. The first is descriptive: to demonstrate a direct assessment for measuring literacy in a population-based survey, and show that it captures variability in skills among young adults, including those with comparable levels of educational attainment. The second aim is to identify whether literacy influences young adults’ health—net of their educational attainment and other confounding factors. Multivariate analyses reveal that literacy is associated with two measures of physical health: self-rated health and prolonged sickness. Because literacy is a key determinant of health, the third aim is to provide insight into how to measure it: can commonly used indirect approaches to estimating literacy (e.g., based on educational attainment or self-reports), accurately capture its prevalence and relationship with health? In a second set of analyses, bivariate results show whether, and the extent to which, indirect measures of literacy overestimate literacy’s prevalence, and multivariate models assess whether indirect estimates of literacy capture its relationship with health. The findings support future efforts to incorporate literacy assessments into population surveys to accurately estimate literacy’s prevalence and health benefits, particularly in contexts like Malawi where access to high-quality schools remains limited. PMID:25164414

  9. Are literacy skills associated with young adults' health in Africa? Evidence from Malawi.

    PubMed

    Smith-Greenaway, Emily

    2015-02-01

    This study investigates whether literacy skills are a distinct dimension of education that influences young adults' health in the southeast African context of Malawi. It uses new data from Tsogolo la Thanzi, a study of young adults in southern Malawi, to achieve three aims. The first is descriptive: to demonstrate a direct assessment for measuring literacy in a population-based survey, and show that it captures variability in skills among young adults, including those with comparable levels of educational attainment. The second aim is to identify whether literacy influences young adults' health - net of their educational attainment and other confounding factors. Multivariate analyses reveal that literacy is associated with two measures of physical health: self-rated health and prolonged sickness. Because literacy is a key determinant of health, the third aim is to provide insight into how to measure it: can commonly used indirect approaches to estimating literacy (e.g., based on educational attainment or self-reports), accurately capture its prevalence and relationship with health? In a second set of analyses, bivariate results show whether, and the extent to which, indirect measures of literacy overestimate literacy's prevalence, and multivariate models assess whether indirect estimates of literacy capture its relationship with health. The findings support future efforts to incorporate literacy assessments into population surveys to accurately estimate literacy's prevalence and health benefits, particularly in contexts like Malawi where access to high-quality schools remains limited. PMID:25164414

  10. Emigration dynamics in southern Africa.

    PubMed

    Milazi, D

    1995-01-01

    This review of the dynamics of international migration in Southern Africa focuses on four aspects of labor migration: 1) while migrant workers suffer from discrimination and lack of protection, there are few alternatives for them; 2) the regulations imposed by the Chamber of Mines in South Africa favor the mining industry at the expense of the workers; 3) worker supplier states have few options for negotiating a commercialized migration policy to achieve economic benefits; and 4) foreign mine workers must unionize in order to escape perpetual subordination. The review opens with a consideration of how migrant mine workers from Botswana, Lesotho, and Swaziland have provided a source of cheap labor which has enhanced the economic prosperity of South Africa. The role of the Chamber of Mines in regulating the supply of labor and employment policy for its members is described. Attention is then turned to Lesotho where land pressure has exacerbated poverty levels. Large-scale migration has led the citizens of Lesotho to consider it a place to live or retire to, not a place to work. Labor migration from Lesotho is organized, is supported by the government, is recurrent, and remains a viable alternative despite faltering demand. The discussion of Lesotho includes a consideration of its political, economic, and demographic situation as well as of ecological factors. Briefer analyses are then provided for Botswana, Swaziland, and Mozambique. The receiving country, South Africa, is shown to be suffering a decline in economic growth which is marked by widespread unemployment. More than 250,000 Whites are prospective emigrants from South Africa. After considering the issues surrounding refugees, regional concerns created by changing economic and political scenarios, and labor strategies which could be adopted by supplier states, the report reiterates a series of recommendations which arose from two major conferences on the problem of unemployment. It is concluded that the

  11. Unprecedented Fires in Southern Africa

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The fires that raged across southern Africa this August and September produced a thick 'river of smoke' over the region. NASA-supported studies currently underway on the event will contribute to improved air pollution policies in the region and a better understanding of its impact on climate change. This year the southern African fire season peaked in early September. The region is subject to some of the highest levels of biomass burning in the world. The heaviest burning was in western Zambia, southern Angola, northern Namibia, and northern Botswana. Some of the blazes had fire fronts 20 miles long that lasted for days. In this animation, multiple fires are burning across the southern part of the African continent in September 2000. The fires, indicated in red, were observed by the Advanced Very High Resolution Radiometer (AVHRR) instrument on board the NOAA-14 satellite. The fires generated large amounts of heat-absorbing aerosols (the dark haze), which were observed with the Earth Probe Total Ozone Mapping Spectrometer (TOMS) instrument. These observations were collected as part of a NASA-supported field campaign called SAFARI 2000 (Southern African Regional Science Initiative). The recent six-week 'dry-season' portion of this experiment was planned to coincide with the annual fires. SAFARI 2000 planners tracked the changing location of fires with daily satellite maps provided by researchers at NASA's Goddard Space Flight Center. 'Every year African biomass burning greatly exceeds the scale of the fires seen this year in the western United States,' says Robert Swap of the University of Virginia, one of the campaign organizers. 'But the southern African fire season we just observed may turn out to be an extreme one even by African standards. It was amazing how quickly this region went up in flames.' The thick haze layer from these fires was heavier than campaign participants had seen in previous field studies in the Amazon Basin and during the Kuwati oil fires

  12. Developing national treatment policy for falciparum malaria in Africa: Malawi experience.

    PubMed

    Malenga, Grace; Wirima, Jack; Kazembe, Peter; Nyasulu, Yohane; Mbvundula, Michael; Nyirenda, Cooper; Sungani, Francis; Campbell, Carl; Molyneux, Malcolm; Bronzan, Rachel; Dodoli, Wilfred; Ali, Doreen; Kabuluzi, Storn

    2009-04-01

    The emergence and spread across sub-Saharan Africa of Plasmodium falciparum resistant to the inexpensive antimalarials chloroquine and sulfadoxine-pyrimethamine has worsened the health and hampered the socio-economic development of affected countries, a situation that calls for urgent review of malaria treatment policies in these countries. The Roll Back Malaria (RBM) initiative promotes strong partnerships for implementing effective malaria control measures. The development of clear policies to guide such implementation at country level offers a way of assessing the achievement of set milestones in this collaborative venture. In this article we describe the policy development process for the treatment of falciparum malaria in Africa, based on experience in Malawi, where the first-line drug treatment was recently changed from sulfadoxine-pyrimethamine to an artemisinin combination therapy. PMID:19285699

  13. Conference on Resource Sharing in Southern and Central Africa (Dar-es-Salaam, Tanzania, December 16-19, 1985). Final Report.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific and Cultural Organization, Paris (France). General Information Programme.

    This document summarizes the activities of a conference held at the Institute of Finance Management in Tanzania on information resource sharing in Southern and Central Africa. Delegates and observers from Lesotho, Swaziland, Mozambique, Botswana, Zimbabwe, Malawi, Zambia, and Tanzania attended the conference. The 15 participants, 8 sponsored by…

  14. Did the 8.2 ka event affect southern Africa?

    NASA Astrophysics Data System (ADS)

    Shaw, Paul

    2014-05-01

    Palaeoenvironmental reconstruction of southern Africa over the past 4 decades has focused largely on the last glacial cycle, and, more recently, events during to Holocene, interpreted largely at the millennial scale. Little attention has been given to sub-millenial drivers and impacts, other than the Little Ice Age (HolmgreN et al 2001). The 8.2ka event has been recognized in Europe for over half a century from peat cores and dendrochronology. A Bond Event caused by disruption of the Gulf Stream by melting Laurentian ice, it lasted around 100 years and resulted in a fall in temperature in northern Europe of up to 6o C. Recently published high-resolution speleothem records have indicated significant short-term change over a much wider area than previously thought, including the Caribbean, eastern Brazil, Spain, Oman and China. A recent paper on Trinidad (Boyd et al, in press) emphasizes a period of prolonged drought in the southern Caribbean due to a southerly emplacement of the ITCZ. The question then arises whether this shift affected the southern hemisphere, and if so, what would be the likely impacts and evidence. A study of late Quaternary lake levels in Lake Chilwa, Malawi (Thomas et al 2009) noted a correspondence between high lake stands and Heinrich events, whilst modeling of Atlantic freshwater influx using the HadCM3 GCM indicates negative precipitation anomalies in the Caribbean and west Africa, with a significant positive anomaly in the interior of southern Africa, possibly linked to enhanced monsoonal activity in the Indian Ocean. These patterns in southern and western Africa have been suggested around 8.2 ka in a review of early Holocene data (Burrough & Thomas 2013), but the chronological resolution is not sufficient to conclude the observation. The only speleothem record for this period, T8 in Cold Air Cave, Makapansgat Valley (Holmgren et al 2003) shows an anomaly, but with temporal resolution at a 50 yr sampling interval, this again is speculative

  15. Waxing and Waning of Forests: Late Quaternary Biogeography of Lake Malawi, Southeast Africa

    NASA Astrophysics Data System (ADS)

    Ivory, S.; Lézine, A. M.; Vincens, A.; Cohen, A. S.

    2014-12-01

    African ecosystems are at great risk due to climate and land-use change. Despite the status of several of these regions as biodiversity hotspots, long-standing ideas about African ecology and biogeography have been unable to be tested until now due to lack of sufficiently long records. Here, we present the first long, continuous terrestrial record of vegetation from Lake Malawi, East Africa which goes back to the early Late Quaternary, permitting us to investigate changes in physiognomy and forest composition over many transitions. In this record, we observe eight phases of forest expansion and collapse. Although diversity is much greater during forest phases, composition varies little from phase to phase. Very high abundances of afromontane taxa suggest frequent widespread colonization of the lowlands by modern high elevation trees. Although there are clear successional stages within each forest such that turnover is great within a single phase, among forest samples between phases, there is little dissimilarity. Each forest phase is interrupted by rapid decline of arboreal taxa and expansion of semi-arid grasslands or woodlands whose composition varies greatly from phase to phase. The variable composition of the more open phases, all occurring during arid periods, is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling within the watershed. This vegetation is unlike any found at Malawi today, with assemblages suggesting strong Somali-Masai affinities. Furthermore, nearly all semi-arid assemblages contain small abundances of forest taxa typically growing in areas with wetter edaphic conditions, suggesting that moist lowland gallery forests were present but restricted to waterways during exceptionally arid times. The waxing and waning of forests throughout this interval has important implications for early human biogeography across Africa as well as disturbance regimes that are crucial for the maintenance of

  16. Global Cicada Sound Collection I: Recordings from South Africa and Malawi by B. W. Price & M. H. Villet and harvesting of BioAcoustica data by GBIF

    PubMed Central

    Price, Benjamin Wills; Rycroft, Simon; Villet, Martin H.

    2015-01-01

    Abstract Background Sound collections for singing insects provide important repositories that underpin existing research (e.g. Price et al. 2007 at http://bio.acousti.ca/node/11801; Price et al. 2010) and make bioacoustic collections available for future work, including insect communication (Ordish 1992), systematics (e.g. David et al. 2003), and automated identification (Bennett et al. 2015). The BioAcoustica platform (Baker et al. 2015) is both a repository and analysis platform for bioacoustic collections: allowing collections to be available in perpetuity, and also facilitating complex analyses using the BioVeL cloud infrastructure (Vicario et al. 2011). The Global Cicada Sound Collection is a project to make recordings of the world's cicadas (Hemiptera: Cicadidae) available using open licences to maximise their potential for study and reuse. This first component of the Global Cicada Sound Collection comprises recordings made between 2006 and 2008 of Cicadidae in South Africa and Malawi. New information This collection of sounds includes 219 recordings of 133 voucher specimens, comprising 42 taxa (25 identified to species, all identified to genus) from South Africa and Malawi. The recordings have been used to underpin work on the species limits of cicadas in southern Africa, including Price et al. (2007) and Price et al. (2010). The specimens are deposited in the Albany Museum, Grahamstown, South Africa (AMGS). The harvesting of acoustic data as occurrence records by GBIF has been implemented by the Scratchpads Team at the Natural History Museum, London. This link increases the value of individual recordings and the BioAcoustica platform within the global infrastructure of biodiversity informatics by making specimen/occurence records from BioAcoustica available to a wider audience, and allowing their integration with other occurence datasets that also contribute to GBIF. PMID:26379465

  17. Determinants of Antiretroviral Therapy Adherence among Women in Southern Malawi: Healthcare Providers' Perspectives

    PubMed Central

    Modeste, Naomi N.; Lee, Jerry W.; Gleason, Peter C.; Maynard-Tucker, Gisele

    2014-01-01

    Background. The purpose of this study was to explore healthcare providers' perspectives on antiretroviral (ART) adherence in two ART clinics in southern Malawi. Nonadherence to ART is a significant hindrance to the success of HIV/AIDS treatment. Methods. A one-on-one semistructured interview was conducted with eight healthcare providers in two ART clinics in rural and urban southern Malawi. The interviews were focused on factors facilitating or hindering ART adherence and strategies to improve adherence. Interviews were audio-recorded, transcribed, and content-analyzed with the use of the constant comparison approach. Results. Of the eight participants, 63% were between the ages of 20 and 30 years and 37% were HIV counselors. Factors facilitating adherence include patients' belief and knowledge, HIV/AIDS education, and a supportive network. Barriers to adherence include discrimination, nondisclosure of HIV status, food insecurity, medication side effects, religion, misinformation, and staff and drug shortages. Strategies to improve adherence were identified by participants to include nutritional/food supplementation for malnourished or undernourished patients and patient counseling. Conclusions. There is a need for collaborative efforts between healthcare providers, patients, and faith-based organizations to identify and address hindrances and facilitators to patients' adherence. Further research is needed to develop strategies addressing religion, staff, and drug shortages. PMID:25610641

  18. Determinants of Antiretroviral Therapy Adherence among Women in Southern Malawi: Healthcare Providers' Perspectives.

    PubMed

    McKinney, Ogbochi; Modeste, Naomi N; Lee, Jerry W; Gleason, Peter C; Maynard-Tucker, Gisele

    2014-01-01

    Background. The purpose of this study was to explore healthcare providers' perspectives on antiretroviral (ART) adherence in two ART clinics in southern Malawi. Nonadherence to ART is a significant hindrance to the success of HIV/AIDS treatment. Methods. A one-on-one semistructured interview was conducted with eight healthcare providers in two ART clinics in rural and urban southern Malawi. The interviews were focused on factors facilitating or hindering ART adherence and strategies to improve adherence. Interviews were audio-recorded, transcribed, and content-analyzed with the use of the constant comparison approach. Results. Of the eight participants, 63% were between the ages of 20 and 30 years and 37% were HIV counselors. Factors facilitating adherence include patients' belief and knowledge, HIV/AIDS education, and a supportive network. Barriers to adherence include discrimination, nondisclosure of HIV status, food insecurity, medication side effects, religion, misinformation, and staff and drug shortages. Strategies to improve adherence were identified by participants to include nutritional/food supplementation for malnourished or undernourished patients and patient counseling. Conclusions. There is a need for collaborative efforts between healthcare providers, patients, and faith-based organizations to identify and address hindrances and facilitators to patients' adherence. Further research is needed to develop strategies addressing religion, staff, and drug shortages. PMID:25610641

  19. Climate and Southern Africa's Water-Energy-Food Nexus

    NASA Astrophysics Data System (ADS)

    Conway, D.; Osborn, T.; Dorling, S.; Ringler, C.; Lankford, B.; Dalin, C.; Thurlow, J.; Zhu, T.; Deryng, D.; Landman, W.; Archer van Garderen, E.; Krueger, T.; Lebek, K.

    2014-12-01

    Numerous challenges coalesce to make Southern Africa emblematic of the connections between climate and the water-energy-food nexus. Rainfall and river flows in the region show high levels of variability across a range of spatial and temporal scales. Physical and socioeconomic exposure to climate variability and change is high, for example, the contribution of electricity produced from hydroelectric sources is over 30% in Madagascar and Zimbabwe and almost 100% in the DRC, Lesotho, Malawi, and Zambia. The region's economy is closely linked with that of the rest of the African continent and climate-sensitive food products are an important item of trade. Southern Africa's population is concentrated in regions exposed to high levels of hydro-meteorological variability, and will increase rapidly over the next four decades. The capacity to manage the effects of climate variability tends, however, to be low. Moreover, with climate change annual precipitation levels, soil moisture and runoff are likely to decrease and rising temperatures will increase evaporative demand. Despite high levels of hydro-meteorological variability, the sectoral and cross-sectoral water-energy-food linkages with climate in Southern Africa have not been considered in detail. Lack of data and questionable reliability are compounded by complex dynamic relationships. We review the role of climate in Southern Africa's nexus, complemented by empirical analysis of national level data on climate, water resources, crop and energy production, and economic activity. Our aim is to examine the role of climate variability as a driver of production fluctuations in the nexus, and to improve understanding of the magnitude and temporal dimensions of their interactions. We first consider national level exposure of food, water and energy production to climate in aggregate economic terms and then examine the linkages between interannual and multi-year climate variability and economic activity, focusing on food and

  20. Modeling rain-fed maize vulnerability to droughts using the standardized precipitation index from satellite estimated rainfall—Southern Malawi case study

    USGS Publications Warehouse

    Funk, Christopher C.; Verdin, James; Adams Chavula; Gregory J. Husak; Harikishan Jayanthi; Tamuka Magadzire

    2013-01-01

    During 1990s, disaster risk reduction emerged as a novel, proactive approach to managing risks from natural hazards. The World Bank, USAID, and other international donor agencies began making efforts to mainstream disaster risk reduction in countries whose population and economies were heavily dependent on rain-fed agriculture. This approach has more significance in light of the increasing climatic hazard patterns and the climate scenarios projected for different hazard prone countries in the world. The Famine Early Warning System Network (FEWS NET) has been monitoring the food security issues in the sub-Saharan Africa, Asia and in Haiti. FEWS NET monitors the rainfall and moisture availability conditions with the help of NOAA RFE2 data for deriving food security status in Africa. This paper highlights the efforts in using satellite estimated rainfall inputs to develop drought vulnerability models in the drought prone areas in Malawi. The satellite RFE2 based SPI corresponding to the critical tasseling and silking phases (in the months of January, February, and March) were statistically regressed with drought-induced yield losses at the district level. The analysis has shown that the drought conditions in February and early March lead to most damage to maize yields in this region. The district-wise vulnerabilities to drought were upscaled to obtain a regional maize vulnerability model for southern Malawi. The results would help in establishing an early monitoring mechanism for drought impact assessment, give the decision makers additional time to assess seasonal outcomes, and identify potential food-related hazards in Malawi.

  1. What are the constraints and opportunities for HIVST scale-up in Africa? Evidence from Kenya, Malawi and South Africa

    PubMed Central

    van Rooyen, Heidi; Tulloch, Olivia; Mukoma, Wanjiru; Makusha, Tawanda; Chepuka, Lignet; Knight, Lucia C; Peck, Roger B; Lim, Jeanette M; Muturi, Nelly; Chirwa, Ellen; Taegtmeyer, Miriam

    2015-01-01

    Introduction HIV self-testing (HIVST) has the potential to increase uptake of HIV testing among untested populations in sub-Saharan Africa and is on the brink of scale-up. However, it is unclear to what extent HIVST would be supported by stakeholders, what policy frameworks are in place and how variations between contexts might influence country-preparedness for scale-up. This qualitative study assessed the perceptions of HIVST among stakeholders in three sub-Saharan countries. Methods Fifty-four key informant interviews were conducted in Kenya (n=16), Malawi (n=26) and South Africa (n=12) with government policy makers, academics, activists, donors, procurement specialists, laboratory practitioners and health providers. A thematic analysis was conducted in each country and a common coding framework allowed for inter-country analysis to identify common and divergent themes across contexts. Results Respondents welcomed the idea of an accurate, easy-to-use, rapid HIV self-test which could increase testing across all populations. High-risk groups, such as men, Men who have sex with men (MSM), couples and young people in particular, could be targeted through a range of health facility and community-based distribution points. HIVST is already endorsed in Kenya, and political support for scale-up exists in South Africa and Malawi. However, several caveats remain. Further research, policy and ensuing guidelines should consider how to regulate, market and distribute HIVST, ensure quality assurance of tests and human rights, and critically, link testing to appropriate support and treatment services. Low literacy levels in some target groups would also need context-specific consideration before scale up. World Health Organization (WHO) policy and regulatory frameworks are needed to guide the process in those areas which are new or specific to self-testing. Conclusions Stakeholders in three HIV endemic sub-Saharan countries felt that HIVST will be an important complement to

  2. Mantle Flow Implications across Easter and Southern Africa from Shear Wave Splitting Measurements

    NASA Astrophysics Data System (ADS)

    Ramirez, C.; Nyblade, A.; Bagley, B. C.; Mulibo, G. D.; Tugume, F.; Wysession, M. E.; Wiens, D.; van der Meijde, M.

    2015-12-01

    In this study, we present new shear wave splitting results from broadband seismic stations in Botswana and Namibia, and combine them with previous results from stations in Kenya, Uganda, Tanzania, Malawi, Zambia, South Africa, Mozambique, Zimbabwe, and Angola to further examine the pattern of seismic anisotropy across southern Africa. The new results come from stations in northern Namibia and Botswana, which help to fill in large gaps in data coverage. Our preliminary results show that fast polarization directions overall trend in a NE orientation. The most noticeable measurements that deviate from this pattern are located around the Archean Tanzania Craton in eastern Africa. The general NE pattern of fast polarization directions is attributed to mantle flow linked to the African superplume. Smaller scale variations from this general direction can be explained by shape anisotropy in the lithosphere in magmatic regions in the East African rift system and to fossil anisotropy in the Precambrian lithosphere.

  3. Spatial Distribution, Sources, and Age of Sedimentary Carbon in Lake Malawi, East Africa

    NASA Astrophysics Data System (ADS)

    Kruger, B. R.; Minor, E. C.; Werne, J. P.; Johnson, T. C.

    2011-12-01

    Currently, the source of organic matter to surface sediments of Lake Malawi (East Africa) is unclear; studies of offshore north-basin cores (363 m to 403 m water depth) have produced conflicting results regarding the proportion of aquatic versus terrestrial organic carbon (OC) contained in these sediments. To address this question, ten multi-cores were recovered from the north basin of Lake Malawi along a transect that follows a major river delta into the lake's deep basin, from 82 m to 386 m water depth. Bulk surface sediment data indicate that while the C/N ratio of organic matter decreases with distance from shore (ranging from 9.8 to 8.3, R2 = 0.58), and stable carbon isotope values become increasingly 13C-depleted (ranging from -21.65 to -25.25, R2 = 0.80), the concentration of OC (wt %) generally increases (ranging from 1.9% to 4.5%, R2 = 0.77). These combined trends suggest substantial carbon contribution from aquatic sources, particularly in the deeper-water, open-lake sites. This trend is supported by preliminary biomarker results. N-alcohols from surface sediments were isolated and grouped into aquatically sourced (C20, C22, and C24) and terrestrially sourced (C28 and C30) fractions for quantification as well as radiocarbon dating. N-alcohol abundance results indicate consistent contribution of terrestrial n-alcohols to surface sediments as distance from shore increases, while aquatic n-alcohol input appears to increase. Preliminary results from compound class specific radiocarbon dating indicate that aquatically sourced n-alcohols isolated from surface sediments may be significantly aged relative to bulk surface sediment.

  4. Indigenous Astronomy in Southern Africa

    NASA Astrophysics Data System (ADS)

    Medupe, Thebe Rodney

    The cultural Astronomy of Southern African peoples has been a subject of many studies spanning atleast over a century. Some of the studies were biased against the notion that Southern African could have any interest in studying the natural environment to benefit their societies. In this chapter, I summarize the current knowledge about cultural Astronomy of Southern African peoples and highlight points of further research.

  5. Emissions from savanna fires in southern Africa

    NASA Astrophysics Data System (ADS)

    Sinha, Parikhit

    2004-12-01

    Airborne measurements are presented of emissions from savanna fires in southern Africa during the dry season. Measurements were obtained aboard the University of Washington Convair-580 research aircraft during the SAFARI 2000 field project in August and September 2000. Savanna fires in southern Africa emit a wide range of gaseous and particulate species including carbon, sulfur, nitrogen, halogen, and oxygenated compounds. Emission factors, emission ratios, and regional emissions of fifty trace gas and particulate species were derived, including eight species not previously reported in the literature (dimethyl sulfide, methyl nitrate, five species of hydrocarbons, and particles with diameters from 0.1--3 mum diameter). The physical, chemical, and radiative properties of the plume from a large savanna fire in South Africa are characterized, including plume dimensions, secondary formation of ozone and organic acids, oxidation of hydrocarbons, coagulation of particles, and gas-to-particle conversion in aged smoke. Numerous fires, thermodynamically stable layers aloft, and large-scale anticylonic flow result in high concentrations of air pollution distributed throughout the lower troposphere over southern Africa during the dry season. Average regional concentrations of CO (261 +/- 81 ppbv), SO2 (2.5 +/- 1.6 ppbv), O3 (64 +/- 13 ppbv), black particulate carbon (2.3 +/- 1.9 mug m-3), organic particulate carbon (6.2 +/- 5.2 mug m-3), total particle mass (26.0 +/- 4.7 mug m-3) are comparable to those found in polluted urban environments. The GEOS-CHEM model of tropospheric chemistry is used to characterize the transport of biomass burning emissions from southern Africa to the neighboring Atlantic and Indian Oceans during the dry season (May--October) of 2000. A large quantity of biomass burning emissions from southern Africa is transported westward over the latitudes 0--20°S to the southern Atlantic Ocean (˜40 Tg CO from May--October), contributing to a pollution anomaly

  6. An evaluation of soil erosion hazard: A case study in Southern Africa using geomatics technologies

    NASA Astrophysics Data System (ADS)

    Eiswerth, Barbara Alice

    Accelerated soil erosion in Malawi, Southern Africa, increasingly threatens agricultural productivity, given current and projected population growth trends. Previous attempts to document soil erosion potential have had limited success, lacking appropriate information and diagnostic tools. This study utilized geomatics technologies and the latest available information from topography, soils, climate, vegetation, and land use of a watershed in southern Malawi. The Soil Loss Estimation Model for Southern Africa (SLEMSA), developed for conditions in Zimbabwe, was evaluated and used to create a soil erosion hazard map for the watershed under Malawi conditions. The SLEMSA sub-models of cover, soil loss, and topography were computed from energy interception, rainfall energy, and soil erodibility, and slope length and steepness, respectively. Geomatics technologies including remote sensing and Geographic Information Systems (GIS) provided the tools with which land cover/land use, a digital elevation model, and slope length and steepness were extracted and integrated with rainfall and soils spatial information. Geomatics technologies enable rapid update of the model as new and better data sets become available. Sensitivity analyses of the SLEMSA model revealed that rainfall energy and slope steepness have the greatest influence on soil erosion hazard estimates in this watershed. Energy interception was intermediate in sensitivity level, whereas slope length and soil erodibility ranked lowest. Energy interception and soil erodibility were shown by parameter behavior analysis to behave in a linear fashion with respect to soil erosion hazard, whereas rainfall energy, slope steepness, and slope length exhibit non-linear behavior. When SLEMSA input parameters and results were compared to alternative methods of soil erosion assessment, such as drainage density and drainage texture, the model provided more spatially explicit information using 30 meter grid cells. Results of this

  7. Comparing the job satisfaction and intention to leave of different categories of health workers in Tanzania, Malawi, and South Africa

    PubMed Central

    Blaauw, Duane; Ditlopo, Prudence; Maseko, Fresier; Chirwa, Maureen; Mwisongo, Aziza; Bidwell, Posy; Thomas, Steve; Normand, Charles

    2013-01-01

    Background Job satisfaction is an important determinant of health worker motivation, retention, and performance, all of which are critical to improving the functioning of health systems in low- and middle-income countries. A number of small-scale surveys have measured the job satisfaction and intention to leave of individual health worker cadres in different settings, but there are few multi-country and multi-cadre comparative studies. Objective The objective of this study was to compare the job satisfaction and intention to leave of different categories of health workers in Tanzania, Malawi, and South Africa. Methods We undertook a cross-sectional survey of a stratified cluster sample of 2,220 health workers, 564 from Tanzania, 939 from Malawi, and 717 from South Africa. Participants completed a self-administered questionnaire, which included demographic information, a 10-item job satisfaction scale, and one question on intention to leave. Multiple regression was used to identify significant predictors of job satisfaction and intention to leave. Results There were statistically significant differences in job satisfaction and intention to leave between the three countries. Approximately 52.1% of health workers in South Africa were satisfied with their jobs compared to 71% from Malawi and 82.6% from Tanzania (χ2=140.3, p<0.001). 18.8% of health workers in Tanzania and 26.5% in Malawi indicated that they were actively seeking employment elsewhere, compared to 41.4% in South Africa (χ2=83.5, p<0.001). The country differences were confirmed by multiple regression. The study also confirmed that job satisfaction is statistically related to intention to leave. Conclusions We have shown differences in the levels of job satisfaction and intention to leave between different groups of health workers from Tanzania, Malawi, and South Africa. Our results caution against generalising about the effectiveness of interventions in different contexts and highlight the need for less

  8. Archean sedimentation and tectonics in southern Africa

    NASA Technical Reports Server (NTRS)

    Kidd, W. S. F.

    1984-01-01

    Sequences in the Barberton Mountain Land greenstone belt (southern Africa) were examined to determine the nature of the sedimentary rocks, their tectonic implications, and their bearing on the present large-scale structural condition of the belt. Also assessed was whether there was evidence for a significant component of shallow-water-deposited sedimentary rocks in the parent materials of the Limpopo belt. The nature of a largehigh strain zone on the southern margin of the central Limpopo belt was examined.

  9. Stable isotope-based Plio-Pleistocene southern hemisphere climate and vegetation reconstructions (Chiwondo Beds, Northern Malawi)

    NASA Astrophysics Data System (ADS)

    Luedecke, T.; Thiemeyer, H.; Schrenk, F.; Mulch, A.

    2013-12-01

    Oxygen and carbon isotope geochemistry of multi-proxy archives is a powerful tool to reconstruct paleoclimatic and paleoenvironmental conditions in particular when climate seasonality plays a key role in the evolution of ecosystems. Here we present the first pedogenic Plio-Pleistocene long-term East-African carbon, oxygen and clumped isotope (Δ47) records from some of the earliest hominid fossil sites in Eastern Africa. The studied 5.0 to 0.6 Ma paleosol, fluviatile, and lacustrine deposits of the Chiwondo Beds (Karonga-Chilumba area, NE shore of Lake Malawi) comprise abundant pedogenic carbonates and fossil remains of a diverse fauna which are dominated by large terrestrial mammals. The sediments are also home to two hominid fossil finds, a maxillary fragment of Paranthropus boisei and a mandible of Homo rudolfensis, both dated around 2.4 Ma. Here, we present stable carbon (δ13C) and oxygen (δ18O) isotope data from fossil enamel of different suid, bovid, and equid species as well as δ13C and δ18O values of pedogenic carbonate. We complement the latter by clumped isotope data as proxy for soil temperature. Our data represent the first southern hemisphere record in the East African Rift (EAR), a region particularly interesting for reconstructing vegetation patterns and correlating these across the ITCZ with data on the evolution and migration of early hominids. As our study site is situated between the well-known hominid-bearing sites of eastern and southern Africa it fills an important geographical gap for early hominid research. The δ13C values of enamel and pedogenic carbonate assess the evolutionary history of C3 and C4 biomass which is closely linked to climate patterns in the Malawi Rift Valley during the time of early hominid evolution. The reconstruction of the development of C4-grasslands give insights of changing atmospheric CO2-concentration, seasonality and distribution of precipitation, and the retreat of tree cover. Results of almost 500

  10. Ash from the Toba supereruption in Lake Malawi shows no volcanic winter in East Africa at 75 ka

    PubMed Central

    Lane, Christine S.; Chorn, Ben T.; Johnson, Thomas C.

    2013-01-01

    The most explosive volcanic event of the Quaternary was the eruption of Mt. Toba, Sumatra, 75,000 y ago, which produced voluminous ash deposits found across much of the Indian Ocean, Indian Peninsula, and South China Sea. A major climatic downturn observed within the Greenland ice cores has been attributed to the cooling effects of the ash and aerosols ejected during the eruption of the Youngest Toba Tuff (YTT). These events coincided roughly with a hypothesized human genetic bottleneck, when the number of our species in Africa may have been reduced to near extinction. Some have speculated that the demise of early modern humans at that time was due in part to a dramatic climate shift triggered by the supereruption. Others have argued that environmental conditions would not have been so severe to have such an impact on our ancestors, and furthermore, that modern humans may have already expanded beyond Africa by this time. We report an observation of the YTT in Africa, recovered as a cryptotephra layer in Lake Malawi sediments, >7,000 km west of the source volcano. The YTT isochron provides an accurate and precise age estimate for the Lake Malawi paleoclimate record, which revises the chronology of past climatic events in East Africa. The YTT in Lake Malawi is not accompanied by a major change in sediment composition or evidence for substantial temperature change, implying that the eruption did not significantly impact the climate of East Africa and was not the cause of a human genetic bottleneck at that time. PMID:23630269

  11. Exposure to violence predicts poor educational outcomes in young children in South Africa and Malawi

    PubMed Central

    Sherr, L.; Hensels, I. S.; Skeen, S.; Tomlinson, M.; Roberts, K. J.; Macedo, A.

    2016-01-01

    Background Violence during childhood may affect short and long-term educational factors. There is scant literature on younger children from resource poor settings. Methods This study assessed child violence experiences (harsh punishment and exposure to domestic or community violence) and school enrolment, progress and attendance in children attending community-based organisations in South Africa and Malawi (n=989) at baseline and at 15 months' follow-up, examining differential experience of HIV positive, HIV affected and HIV unaffected children. Results Violence exposure was high: 45.4% experienced some form of psychological violence, 47.8% physical violence, 46.7% domestic violence and 41.8% community violence. Primary school enrolment was 96%. Violence was not associated with school enrolment at baseline but, controlling for baseline, children exposed to psychological violence for discipline were more than ten times less likely to be enrolled at follow-up (OR 0.09; 95% CI 0.01 to 0.57). Harsh discipline was associated with poor school progress. For children HIV positive a detrimental effect of harsh physical discipline was found on school performance (OR 0.10; 95% CI 0.02 to 0.61). Conclusion Violence experiences were associated with a number of educational outcomes, which may have long-term consequences. Community-based organisations may be well placed to address such violence, with a particular emphasis on the challenges faced by children who are HIV positive. PMID:26678567

  12. River Knick Points of Southern Africa

    NASA Astrophysics Data System (ADS)

    Crossley, R.; Markwick, P.

    2005-12-01

    Successful interpretation of the longitudinal profiles of rivers in southern Africa requires identification of the relative roles of bedrock geology, tectonics, river capture history, climatic change and eustasy. Knick points, expressed as waterfalls or as changes in gradient, are examined for the Kunene, Orange, Zambezi and Shire Rivers utilising Shuttle Imaging Radar topographic data, Gtopo 30 topographic data, Hydro 1K drainage data, satellite imagery, zoogeography and fieldwork. The results provide insights into what can, and cannot, be inferred about the uplift history of Africa.

  13. Retinitis pigmentosa in southern Africa.

    PubMed

    Greenberg, J; Bartmann, L; Ramesar, R; Beighton, P

    1993-11-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal disorders which are a common cause of genetic blindness. The relative frequencies of the different forms of RP in South Africa, as determined from the register at the DNA banking centre for RP at the Department of Human Genetics, University of Cape Town, are presented and discussed. Of the 125 families analysed, 29 (23%) showed autosomal dominant, 33 (27%) autosomal recessive and 3 (3%) X-linked inheritance. In 10 families the pedigree data were insufficient to allow accurate genetic subtyping and a further 50 patients were sporadic without a family history of RP or other syndromic features which would allow categorization. PMID:8313621

  14. A Progressively Wetter Climate in Southern East Africa Over the Past 1.3 Million Years

    NASA Astrophysics Data System (ADS)

    Berke, M. A.; Johnson, T. C.; Werne, J. P.; Contreras, S.; Brown, E. T.

    2015-12-01

    We present a 1.3 million year record of hydroclimate in the basin of Lake Malawi, the second deepest lake in Africa, located at ~10 - 15ºS latitude in the East African Rift Valley. The lake is ~550 km long, has a maximum depth of 706 m, and is presently anoxic below ~200 m. While the lake is an open basin today with outflow through the Shire River at its southern end, the surface of Lake Malawi has dropped well below the elevation of its outlet on several occasions in its past. We examined a 380 m sediment sequence taken from a water depth of 590 m, from Cores MAL05-1B and MAL05-1C of the Lake Malawi Drilling Project. Sediment samples were analyzed for the carbon isotopic composition of the C29 - C33 n-alkanes derived from fossil leaf waxes, which primarily reflect the relative abundance of C3 (mostly trees and shrubs) and C4 (mostly grass) vegetation, i.e., relatively humid or arid conditions, respectively, in the lake basin. The δ13Cwax record portrays a transition from a highly variable and predominantly arid climate prior to 900 ka to a progressively more humid environment after the Mid-Pleistocene Transition, dominated by 100 ky cycles consisting of warm, wet interglacial periods alternating with relatively cool, dry glacial periods. This shift towards more humid conditions in the Lake Malawi basin contrasts with the well-documented progression towards a more arid environment in North Africa over the same period, as reflected in the carbon isotopic record of soil carbonates and in dust records from marine sediment recovered from the Atlantic Ocean and Gulf of Aden. Aridification in the Horn of Africa has been attributed to a cooling of the Indian Ocean. Model results suggest that this would be accompanied by a weakening of a localized Walker circulation over the Indian Ocean, less ascending air over the western Indian Ocean and coastal Africa, and more precipitation in the Rift Valley.

  15. The Seismotectonic Model of Southern Africa

    NASA Astrophysics Data System (ADS)

    Midzi, Vunganai; Mulabisana, Thifelimbulu; Manzunzu, Brassnavy

    2013-04-01

    Presented in this report is a summary of the major structures and seismotectonic zones in Southern Africa (Botswana, Lesotho, Namibia, South Africa and Swaziland), which includes available information on fault plane solutions and stress data. Reports published by several experts contributed much to the prepared zones. The work was prepared as part of the requirements for the SIDA/IGCP Project 601 titled "Seismotectonics and Seismic Hazards in Africa" as well as part of the seismic source characterisation of the GEM-Africa Seismic hazard study. The seismic data used are part of the earthquake catalogue being prepared for the GEM-Africa project, which includes historical and instrumental records as collected from various agencies. Seventeen seismic zones/sources were identified and demarcated using all the available information. Two of the identiied sources are faults with reliable evidence of their activity. Though more faults have been identified in unpublished material as being active, more work is being carried out to obtain information that can be used to characterise them before they are included in the seismotectonic model. Explanations for the selected boundaries of the zones are also given in the report. It should be noted that this information is the first draft of the seismic source zones of the region. Futher interpreation of the data is envisaged which might result in more than one version of the zones.

  16. HIV Risk Perceptions, the Transition to Marriage, and Divorce in Southern Malawi.

    PubMed

    Grant, Monica J; Soler-Hampejsek, Erica

    2014-09-01

    Little is known about whether the timing of marriage is used as a strategy to avoid HIV infection among young people in sub-Saharan Africa. Analyzing five rounds of longitudinal data from the Malawi Schooling and Adolescent Survey, we do not find support for the hypothesis that young women's perceived chances of future HIV infection are associated with the transition to marriage, but we do find evidence that young married women who see themselves as at risk of future infection have a greater likelihood of divorcing than do women who perceive no chance of future infection. We also use individual-level fixed-effects regressions to examine how the transition to marriage affects respondents' expectations of future HIV infection. Respondents are consistently more likely to perceive any chance of future HIV infection in the years following marriage than in the years preceding it. Our findings suggest that young women revise their risk perceptions based on their marital experiences and that divorce may serve as a protective strategy for young married women concerned about their chance of future HIV infection. PMID:25207495

  17. Middle to Late Pleistocene vegetation and climate change in subtropical southern East Africa

    NASA Astrophysics Data System (ADS)

    Castañeda, Isla S.; Caley, Thibaut; Dupont, Lydie; Kim, Jung-Hyun; Malaizé, Bruno; Schouten, Stefan

    2016-09-01

    In this study we investigate Pleistocene vegetation and climate change in southern East Africa by examining plant leaf waxes in a marine sediment core that receives terrestrial runoff from the Limpopo River. The plant leaf wax records are compared to a multi-proxy sea surface temperature (SST) record and pollen assemblage data from the same site. We find that Indian Ocean SST variability, driven by high-latitude obliquity, exerted a strong control on the vegetation of southern East Africa during the past 800,000 yr. Interglacial periods were characterized by relatively wetter and warmer conditions, increased contributions of C3 vegetation, and higher SST, whereas glacial periods were marked by cooler and arid conditions, increased contributions of C4 vegetation, and lower SST. We find that Marine Isotope Stages (MIS) 5e, 11c, 15e and 7a-7c are strongly expressed in the plant leaf wax records but MIS 7e is absent while MIS 9 is rather weak. Our plant leaf wax records also record the climate transition associated with the Mid-Brunhes Event (MBE) suggesting that the pre-MBE interval (430-800 ka) was characterized by higher inputs from grasses in comparison to relatively higher inputs from trees in the post-MBE interval (430 to 0 ka). Differences in vegetation and SST of southern East Africa between the pre- and post-MBE intervals appear to be related to shifts in the location of the Subtropical Front. Comparison with vegetation records from tropical East Africa indicates that the vegetation of southern East Africa, while exhibiting glacial-interglacial variability and notable differences between the pre- and post-MBE portions of the record, likely did not experience such dramatic extremes as occurred to the north at Lake Malawi.

  18. AIDS in Southern Africa: a major factor in planning for the region.

    PubMed

    Place, J L

    1990-01-01

    This article discusses the spread and impact of AIDS in Southern Africa, as well as government responses to the pandemic. A with a total of 14,325 reported AIDS cases as of September 1990, the countries the Southern Africa (Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Zambia, and Zimbabwe) now account for 20% of all AIDS cases in Africa. This represents an eightfold increase in just over 2 years. Because of the young age structure of the population, which in the next few years will become sexually active, experts fear rapid increases in the rate of infection. With the exception of South Africa, AIDS has struck men and women alike. The region has also witnessed a growing number of HIV-infected babies and children orphaned by the disease. Besides its cost in human lives, the spread of AIDs threatens the economic development of the region, as it effects the most productive segment of the population, and as the resources to combat the disease dwindle, while its destructive potential grows. Surveillance of the disease has proven difficult, especially among refugees and returning exiles. Government responses to the pandemic have differed. In Zambia, where President Kaunda's own son died of the disease, the government has adopted an extensive AIDS program. Kaunda has appealed for a compassionate treatment of people with AIDS. The South African response, however, has met great skepticism. Most of the AIDS cases have been among blacks and homosexuals, 2 groups that have been marginalized by society. Nonetheless, the region has seen a bright note with the formation of the Southern Africa Network of AIDS Service Organization, which is designed to promote cooperation in combating the spread of AIDS. PMID:12284198

  19. Malaria epidemiology and control in Southern Africa.

    PubMed

    Mharakurwa, Sungano; Thuma, Philip E; Norris, Douglas E; Mulenga, Modest; Chalwe, Victor; Chipeta, James; Munyati, Shungu; Mutambu, Susan; Mason, Peter R

    2012-03-01

    The burden of malaria has decreased dramatically within the past several years in parts of sub-Saharan Africa, following the scale-up of interventions supported by the Roll Back Malaria Partnership, the President's Malaria Initiative and other partners. It is important to appreciate that the reductions in malaria have not been uniform between and within countries, with some areas experiencing resurgence instead. Furthermore, while interventions have greatly reduced the burden of malaria in many countries, it is also recognized that the malaria decline pre-dated widespread intervention efforts, at least in some cases where data are available. This raises more questions as what other factors may have been contributing to the reduction in malaria transmission and to what extent. The International Center of Excellence for Malaria Research (ICEMR) in Southern Africa aims to better understand the underlying malaria epidemiology, vector ecology and parasite genomics using three contrasting settings of malaria transmission in Zambia and Zimbabwe: an area of successful malaria control, an area of resurgent malaria and an area where interventions have not been effective. The Southern Africa ICEMR will capitalize on the opportunity to investigate the complexities of malaria transmission while adapting to intervention and establish the evidence-base to guide effective and sustainable malaria intervention strategies. Key approaches to attain this goal for the region will include close collaboration with national malaria control programs and contribution to capacity building at the individual, institutional and national levels. PMID:21756864

  20. The Relationship between Partners’ Family-Size Preferences in Southern Malawi

    PubMed Central

    Yeatman, Sara; Sennott, Christie

    2015-01-01

    Studies of the relative influence of partners’ fertility preferences on behaviors tend to treat preferences as fixed, largely independent traits despite existing theoretical arguments and empirical evidence suggesting that they are moving targets that may be jointly developed within relationships. In this study, we use couple-level panel data from married and unmarried young adults in southern Malawi to examine the relationship between partners’ family-size preferences. We find evidence of assortative mating: young Malawians are more likely to partner with individuals who have similar family-size goals. Additionally, although partners’ family-size preferences do not perfectly converge, changes among men’s and women’s preferences are significantly more likely to be “toward” than “away from” those of their partner. Our findings point to a need for studies regarding the relative influence of partners on reproductive outcomes to consider the interdependence of partners’ preferences and the varied ways in which partners can influence shared reproductive behaviors. PMID:25207497

  1. Orbital- versus glacial-mode forcing of tropical African climate: Results of scientific drilling in Lake Malawi, East Africa

    NASA Astrophysics Data System (ADS)

    Scholz, C. A.; Cohen, A. S.; Johnson, T. C.; King, J. W.; Brown, E. T.; Lyons, R. P.; Stone, J. R.; Beuning, K. R.

    2007-12-01

    Lake Malawi extends from 9-14 degrees S within the East African Rift Valley, and at 700 m deep, contains more than 20 percent of the surface water on the African continent. In 2005 the Lake Malawi Scientific Drilling Project drilled 7 holes at two sites in the lake, recovering a continuous sediment record that samples much of the Quaternary. Detailed studies completed to date on sediments deposited during the past 145 ka indicate periods of severe aridity at precessional frequency between 135 and 75 ka, when the lake's water volume was periodically reduced by at least 95 percent. These dramatic drops in lake level (more than 550 m), signifying markedly arid conditions in the catchment, are documented in sediment lithology (decreased organic carbon content and increased authigenic carbonate content during severe lowstands), aquatic microfossils (appearance of a littoral ostracode fauna, and saline/alkaline lake diatom flora during extreme low lake stages), as well as in dramatic reductions in catchment pollen production. These intervals of pronounced tropical African aridity in the early late-Pleistocene were much more severe than the Last Glacial Maximum, and are consistent with sediment records from Lakes Tanganyika (East Africa) and Bosumtwi (West Africa). In all three lakes a major rise in water levels and a shift to more humid conditions is observed after ~70 ka. The transition to wetter, more stable conditions coincides with the relaxation of orbital eccentricity and a reduction in the amplitude of precession. The observed climate mode switch to decreased environmental variability is consistent with terrestrial and marine records from in and around tropical Africa, but these new drill cores provide evidence for dramatically drier conditions prior to 70 ka that have not as yet been detected in marine sediment records. Such climate change may have stimulated the expansion and migrations of early modern human populations.

  2. Climate change and wildfire around southern Africa

    NASA Astrophysics Data System (ADS)

    Kimura, K.

    2013-12-01

    When the climate change in southern Africa is analyzed, the effects of rainfall by Inter Tropical Convergence Zone(ITCZ) and cyclone are important. In this study, the rainfall patterns are analyzed with synoptic analysis. The southern limit of ITCZ is around the arid zone around Namibia, Botswana, Zimbabwe and Mozambique. This zone has some effects of both ITCZ and extratropical cyclones by season. As well as this, the eastern part of this area has heavy rainfall by the cyclone from the Indian Ocean once in several years. In the other hand, a lot of wildfire occurs in this area. The main cause of the wildfire is anthropogenic misbehavior of the fire by the slash-and-burn agriculture. Recently we can find the wildfire detected with the satellite imagery like Terra/Aqua MODIS. We can compare the weather environment and the wildfire occurrence with Geographical Information System. We have tried making the fire weather index suitable for the southern African semi-arid area.

  3. Hydrological projections under climate change in the near future by RegCM4 in Southern Africa using a large-scale hydrological model

    NASA Astrophysics Data System (ADS)

    Li, Lu; Diallo, Ismaïla; Xu, Chong-Yu; Stordal, Frode

    2015-09-01

    This study aims to provide model estimates of changes in hydrological elements, such as EvapoTranspiration (ET) and runoff, in Southern Africa in the near future until 2029. The climate change scenarios are projected by a high-resolution Regional Climate Model (RCM), RegCM4, which is the latest version of this model developed by the Abdus Salam International Centre for Theoretical Physics (ICTP). The hydrological projections are performed by using a large-scale hydrological model (WASMOD-D), which has been tested and customized on this region prior to this study. The results reveal that (1) the projected temperature shows an increasing tendency over Southern Africa in the near future, especially eastward of 25°E, while the precipitation changes are varying between different months and sub-regions; (2) an increase in runoff (and ET) was found in eastern part of Southern Africa, i.e. Southern Mozambique and Malawi, while a decrease was estimated across the driest region in a wide area encompassing Kalahari Desert, Namibia, southwest of South Africa and Angola; (3) the strongest climate change signals are found over humid tropical areas, i.e. north of Angola and Malawi and south of Dem Rep of Congo; and (4) large spatial and temporal variability of climate change signals is found in the near future over Southern Africa. This study presents the main results of work-package 2 (WP2) of the 'Socioeconomic Consequences of Climate Change in Sub-equatorial Africa (SoCoCA)' project, which is funded by the Research Council of Norway.

  4. Projected changes in Malawi's growing season

    NASA Astrophysics Data System (ADS)

    Vizy, Edward K.; Cook, Kerry H.; Chimphamba, James; McCusker, Brent

    2015-09-01

    Regional climate model projections at 30-km resolution are used to predict future mid-century and late-century growing season changes over Malawi due to global warming under the Representative Concentration Pathway 8.5 business-as-usual emissions forcing scenario. Three different methods for estimating growing season characteristics are applied and evaluated. All three methods yield reasonable growing season length, onset, and demise date estimates over Malawi given the wide range of uncertainty of the observations. The projections indicate the likelihood for a shorter growing season in the future over Malawi south of 13.5°S. At mid-century the growing season length is predicted to be 20-40 % (20-55 days) shorter over the southernmost districts and 5-20 % (5-30 days) shorter over the central districts. By late-century the length is predicted to be 25-55 % (20-70 days) shorter with significant differences extending into northern Malawi. The shorter growing season is primarily associated with an earlier demise date, as no significant change in the onset date is predicted. Analysis of the regional circulation and horizontal moisture flux transport indicates that the earlier demise is associated with an intensification of the thermal low over the Kalahari Desert to the south and west of Malawi and an expansion of the mid-tropospheric Kalahari anticyclone over southern Africa. The stronger thermal low/anticyclone enhances the moisture flux divergence over Malawi suppressing the convective activity at the end of the wet season.

  5. Hydrological model uncertainty assessment in southern Africa

    NASA Astrophysics Data System (ADS)

    Hughes, D. A.; Kapangaziwiri, E.; Sawunyama, T.

    2010-06-01

    The importance of hydrological uncertainty analysis has been emphasized in recent years and there is an urgent need to incorporate uncertainty estimation into water resources assessment procedures used in the southern Africa region. The region is characterized by a paucity of accurate data and limited human resources, but the need for informed development decisions is critical to social and economic development. One of the main sources of uncertainty is related to the estimation of the parameters of hydrological models. This paper proposes a framework for establishing parameter values, exploring parameter inter-dependencies and setting parameter uncertainty bounds for a monthly time-step rainfall-runoff model (Pitman model) that is widely used in the region. The method is based on well-documented principles of sensitivity and uncertainty analysis, but recognizes the limitations that exist within the region (data scarcity and accuracy, model user attitudes, etc.). Four example applications taken from different climate and physiographic regions of South Africa illustrate that the methods are appropriate for generating behavioural stream flow simulations which include parameter uncertainty. The parameters that dominate the model response and their degree of uncertainty vary between regions. Some of the results suggest that the uncertainty bounds will be too wide for effective water resources decision making. Further work is required to reduce some of the subjectivity in the methods and to investigate other approaches for constraining the uncertainty. The paper recognizes that probability estimates of uncertainty and methods to include input climate data uncertainties need to be incorporated into the framework in the future.

  6. Evidence of nutrition transition in Southern Africa.

    PubMed

    Nnyepi, Maria S; Gwisai, Namo; Lekgoa, Malebogo; Seru, Tumelo

    2015-11-01

    Nutrition transition is characterised by shift to highly refined diets high in fat, salt and caloric sweeteners and low in fibre in rapidly growing economies. Dietary shifts occur almost concurrently with demographic and epidemiologic shifts, urbanisation and industrialisation and together contribute to increased prevalence of nutrition related (NR)-non-communicable disease (NCR). The emergence of nutrition transition in Southern Africa countries (SAC) was examined using anthropometric, NCD prevalence, and food consumption data. The findings reveal growing prevalence of overweight and obesity (OWOB) across SAC, with national prevalence estimated between 30 and 60 % in all but two SAC. Overweight prevalence in excess of 60 % has been reported in some sub-population groups. Hypertension prevalence of at least 30 % has also been reported. Further, the prevalence of OWOB and hypertension in many SAC exceeds that of HIV and is often at par with stunting in children. NCD are equally serious public health problems as stunting and HIV. Collectively, NR-NCD explain 20-31 % of mortality for Botswana, South Africa, Swaziland, Mozambique and Zambia. At least 72 % of adults in SAC have fewer servings of fruit and vegetable servings daily than recommended. Additionally, adults in SAC do poorly in physical activity; 31-75 % do not exercise regularly. Not surprisingly, 15-40 % of adults in SAC have at least three risk factors of CVD. SAC are grappling with NR-NCD which threaten to surpass infectious diseases burden. SAC are at various levels in interventions for moving their populations to stage 5, but there is room for much improvement. PMID:25686639

  7. National and Local Sources of Power: Important Considerations for Teacher Education Reforms in Rural Malawi

    ERIC Educational Resources Information Center

    Chazema, Jacqueline; O'Meara, James

    2011-01-01

    The establishment of formal teacher training systems is a relatively new innovation in some parts of Africa. Formal training of secondary teachers in Malawi commenced when the government of Malawi opened the University of Malawi in 1965. The contribution of Malawi's ruling parties to the development of teacher education in Malawi since then is an…

  8. Stars and Seasons in Southern Africa

    NASA Astrophysics Data System (ADS)

    Snedegar, K. V.

    Although the indigenous people of Southern Africa traditionally viewed the sky as a place quite apart from the Earth, they believed celestial phenomena to be natural signs united with those of the Earth in a harmonious synchronicity. There is no substantial evidence that the precolonial Africans imagined a casual relationship between celestial bodies and the seasonal patterns of life on Earth. They did, however, recognize a coincidental relationship. The traditional African cosmos, then, worked as a noetic principle unifying the observed motions of celestial bodies, the sequence of seasons, and the behavior of plants and animals. Such a cosmos, with local peculiarities, was widely understood in Southern Africa before the end of the last century. By the early 20th century European colonial paradigms had largely obliterated this African worldview. This paper will offer a partial reconstruction. Pre-colonial South African people viewed time as a sequence of discrete natural events; through annual repetition these events served as a guide for proper human action. The South Africans analyzed the passage of time in terms of the motions of celestial bodies, the maturation of beneficial plants, and the mating patterns of animals. The rightful course of human life was seen to fit within the seasonal context of these natural phenomena. The visibility of conspicuous stars and asterisms marked significant times of year. For instance, the Lovedu people greeted the dawn rising of Canopus with joy: "The boy has come out." The star was a signal for rainmaking and boys' initiation ceremonies to proceed. The Venda constellation Thutlwa, the giraffes, comprises α and β Crucis and α and β Centauri. In October Thutlwa skims the trees of the evening horizon. The Venda Thutlwa literally means 'rising above the trees,' an allusion to the majestic vegetarian creatures and the stars advising the people to be done with their spring planting. This paper will describe stellar associations

  9. Assessing indigenous knowledge systems and climate change adaptation strategies in agriculture: A case study of Chagaka Village, Chikhwawa, Southern Malawi

    NASA Astrophysics Data System (ADS)

    Nkomwa, Emmanuel Charles; Joshua, Miriam Kalanda; Ngongondo, Cosmo; Monjerezi, Maurice; Chipungu, Felistus

    In Malawi, production from subsistence rain fed agriculture is highly vulnerable to climate change and variability. In response to the adverse effects of climate change and variability, a National Adaptation Programme of Action is used as framework for implementing adaptation programmes. However, this framework puts limited significance on indigenous knowledge systems (IKS). In many parts of the world, IKS have shown potential in the development of locally relevant and therefore sustainable adaptation strategies. This study was aimed at assessing the role of IKS in adaptation to climate change and variability in the agricultural sector in a rural district of Chikhwawa, southern Malawi. The study used both qualitative data from focus group and key informant interviews and quantitative data from household interviews and secondary data to address the research objectives. The study established that the local communities are able to recognise the changes in their climate and local environment. Commonly mentioned indicators of changing climatic patterns included delayed and unpredictable onset of rainfall, declining rainfall trends, warming temperatures and increased frequency of prolonged dry spells. An analysis of empirical data corroborates the people's perception. In addition, the community is able to use their IKS to adapt their agricultural systems to partially offset the effects of climate change. Like vulnerability to climate change, IKS varies over a short spatial scale, providing locally relevant adaptation to impacts of climate change. This paper therefore advocates for the integration of IKS in programmes addressing adaptation to climate change and vulnerability. This will serve to ensure sustainable and relevant adaptation strategies.

  10. Educational Reform and the Transformation of Southern Africa.

    ERIC Educational Resources Information Center

    Mungazi, Dickson A.; Walker, L. Kay

    The purpose of this study is to furnish evidence supporting the conclusion that the thrust for the transformation of southern Africa, that region of Africa south of the equator, cannot be initiated without responding to the need for fundamental educational reform. In this study, transformation is defined as basic change in the structure of…

  11. Clean Air Slots Amid Dense Atmospheric Pollution in Southern Africa

    NASA Technical Reports Server (NTRS)

    Hobbs, Peter V.

    2003-01-01

    During the flights of the University of Washington's Convair-580 in the Southern African Regional Science Initiative (SAFARI 2000) in southern Africa, a phenomenon was observed that has not been reported previously. This was the occurrence of thin layers of remarkably clean air, sandwiched between heavily polluted air, which persisted for many hours during the day. Photographs are shown of these clean air slots (CAS), and particle concentrations and light scattering coefficients in and around such slot are presented. An explanation is proposed for the propensity of CAS to form in southern Africa during the dry season.

  12. A continental scale water balance model: a GIS-approach for Southern Africa

    NASA Astrophysics Data System (ADS)

    Alemaw, B. F.; Chaoka, T. R.

    A distributed GIS-based hydrological model is developed using GIS and computational hydrology techniques. The model is based on water balance consideration of the surface and subsurface processes. The surface water balance processes include precipitation infiltration, overland runoff, evapo-transpiration and canopy surface interception losses on daily time steps; The subsurface process considers soil moisture accounting on a monthly basis. The model was used to estimate generated runoff from matrix of specific geo-referenced grids representing Southern Africa. All regional and seasonal dispensation of water balances have been based on standard GIS formats for storage, spatial display and interpretation of results. Considering the 1961-1990 climatic period, we have mapped the regional variation of the mean annual soil moisture (SM), actual evapo-transpiration (AET), and generated runoff (ROF) across Southern Africa or known as the SADC region. The model estimates the mean SM of the region to be about 148 mm/year. There is a wide spatial range in the distribution of SM over the region due to the fact that the absolute soil moisture is dependent on the water retention properties of the soils considered across the region. The model prediction of the mean annual AET in the region reaches a maximum of 1500 mm, with mean 420 mm. The mean annual generated runoff from the land catchment in the region is about 151 mm/year although there is a significant inter-regional variation among the SADC countries, which is a function of the variation in the vegetation cover, soil and climate variation. Lower runoff regimes are dominant in arid areas in Botswana, Namibia and south-western part of the Republic of South Africa. Higher runoff regimes are the Northern and Western Tanzania, along the east coastal portions of Mozambique, central Mozambique, western Zambia and Malawi.

  13. Investigating Preterm Care at the Facility Level: Stakeholder Qualitative Study in Central and Southern Malawi.

    PubMed

    Gondwe, Austrida; Munthali, Alister; Ashorn, Per; Ashorn, Ulla

    2016-07-01

    Objectives Malawi is estimated to have one of the highest preterm birth rates in the world. However, care of preterm infants at facility level in Malawi has not been explored. We aimed to explore the views of health stakeholders about the care of preterm infants in health facilities and the existence of any policy protocol documents guiding the delivery of care to these infants. Methods We conducted 16 in-depth interviews with health stakeholders (11 service providers and 5 policy makers) using an interview guide and asked for any existing policy protocol documents guiding care for preterm infants in the health facilities in Malawi. The collected documents were reviewed and all the interviews were digitally recorded, transcribed and translated. All data were analysed using content analysis approach. Results We identified four policy protocol documents and out of these, one had detailed information explaining the care of preterm infants. Policy makers reported that policy protocol documents to guide care for preterm infants were available in the health facilities but majority (63.6 %) of the service providers lacked knowledge about the existence of these documents. Health stakeholders reported several challenges in caring for preterm infants including lack of trained staff in preterm infant care, antibiotics, space, supervision and poor referral system. Conclusions Our study highlights that improving health care service provider knowledge of preterm infant care is an integral part in preterm child birth. Our findings suggests that policy makers and health decision makers should retain those trained in preterm new born care in the health facility's preterm unit. PMID:26976282

  14. Deltas of the Lake Malawi rift, east Africa: Seismic expression and exploration implications

    SciTech Connect

    Scholz, C.A.

    1995-11-01

    High-resolution, air-gun-sourced seismic reflection surveys over the offshore regions of five river deltas in Lake Malawi in the East African rift system reveal considerable variability in acoustic facies and stratigraphic architecture. This variability can largely be attributed to the influences of different structural settings, and to a lesser degree to high-amplitude (100-400 m) and high-frequency (1000 to 100,000 yr) fluctuations in lake level. Deltas on flexural and axial margins in the rift lake show well-developed progradational geometries. In contrast, a delta on a steep, accommodation zone margin distributes coarse sediments over a broad depositional apron, rather than concentrating sediment in discrete progradational lobes as on the other deltas. A large border fault margin river delta displays the most complex tectonic and stratigraphic architecture of all the deltas studied. It contains several delta-associated facies, including prograding clinoform packages, fan deltas stacked against a boundary fault, and extensive subaqueous fans. Flexural margin lowstand deltas may be the most prospective for hydrocarbon exploration due to their large, internally well-organized, progradational lobes and their close proximity to deep-water, high total organic carbon lacustrine source facies.

  15. Livestock First Reached Southern Africa in Two Separate Events

    PubMed Central

    Sadr, Karim

    2015-01-01

    After several decades of research on the subject, we now know when the first livestock reached southern Africa but the question of how they got there remains a contentious topic. Debate centres on whether they were brought with a large migration of Khoe-speakers who originated from East Africa; or whether the livestock were traded down-the-line among hunter-gatherer communities; or indeed whether there was a long history of diverse small scale population movements in this part of the world, one or more of which ‘infiltrated’ livestock into southern Africa. A new analysis of the distribution of stone toolkits from a sizeable sample of sub-equatorial African Later Stone Age sites, coupled with existing knowledge of the distribution of the earliest livestock remains and ceramics vessels, has allowed us to isolate two separate infiltration events that brought the first livestock into southern Africa just over 2000 years ago; one infiltration was along the Atlantic seaboard and another entered the middle reaches of the Limpopo River Basin. These findings agree well with the latest results of genetic research which together indicate that multiple, small-scale infiltrations probably were responsible for bringing the first livestock into southern Africa. PMID:26295347

  16. Livestock First Reached Southern Africa in Two Separate Events.

    PubMed

    Sadr, Karim

    2015-01-01

    After several decades of research on the subject, we now know when the first livestock reached southern Africa but the question of how they got there remains a contentious topic. Debate centres on whether they were brought with a large migration of Khoe-speakers who originated from East Africa; or whether the livestock were traded down-the-line among hunter-gatherer communities; or indeed whether there was a long history of diverse small scale population movements in this part of the world, one or more of which 'infiltrated' livestock into southern Africa. A new analysis of the distribution of stone toolkits from a sizeable sample of sub-equatorial African Later Stone Age sites, coupled with existing knowledge of the distribution of the earliest livestock remains and ceramics vessels, has allowed us to isolate two separate infiltration events that brought the first livestock into southern Africa just over 2000 years ago; one infiltration was along the Atlantic seaboard and another entered the middle reaches of the Limpopo River Basin. These findings agree well with the latest results of genetic research which together indicate that multiple, small-scale infiltrations probably were responsible for bringing the first livestock into southern Africa. PMID:26295347

  17. Human Rights Violations among Men Who Have Sex with Men in Southern Africa: Comparisons between Legal Contexts

    PubMed Central

    Zahn, Ryan; Grosso, Ashley; Scheibe, Andrew; Bekker, Linda-Gail; Ketende, Sosthenes; Dausab, Friedel; Iipinge, Scholastica; Beyrer, Chris; Trapance, Gift; Baral, Stefan

    2016-01-01

    In 1994, South Africa approved a constitution providing freedom from discrimination based on sexual orientation. Other Southern African countries, including Botswana, Malawi, and Namibia, criminalize same-sex behavior. Men who have sex with men (MSM) have been shown to experience high levels of stigma and discrimination, increasing their vulnerability to negative health and other outcomes. This paper examines the relationship between criminalization of same-sex behavior and experiences of human rights abuses by MSM. It compares the extent to which MSM in peri-urban Cape Town experience human rights abuses with that of MSM in Gaborone, Botswana; Blantyre and Lilongwe, Malawi; and Windhoek, Namibia. In 2008, 737 MSM participated in a cross-sectional study using a structured survey collecting data regarding demographics, human rights, HIV status, and risk behavior. Participants accrued in each site were compared using bivariate and multivariate logistic regression. Encouragingly, the results indicate MSM in Cape Town were more likely to disclose their sexual orientation to family or healthcare workers and less likely to be blackmailed or feel afraid in their communities than MSM in Botswana, Malawi, or Namibia. However, South African MSM were not statistically significantly less likely experience a human rights abuse than their peers in cities in other study countries, showing that while legal protections may reduce experiences of certain abuses, legislative changes alone are insufficient for protecting MSM. A comprehensive approach with interventions at multiple levels in multiple sectors is needed to create the legal and social change necessary to address attitudes, discrimination, and violence affecting MSM. PMID:26764467

  18. Human Rights Violations among Men Who Have Sex with Men in Southern Africa: Comparisons between Legal Contexts.

    PubMed

    Zahn, Ryan; Grosso, Ashley; Scheibe, Andrew; Bekker, Linda-Gail; Ketende, Sosthenes; Dausab, Friedel; Iipinge, Scholastica; Beyrer, Chris; Trapance, Gift; Baral, Stefan

    2016-01-01

    In 1994, South Africa approved a constitution providing freedom from discrimination based on sexual orientation. Other Southern African countries, including Botswana, Malawi, and Namibia, criminalize same-sex behavior. Men who have sex with men (MSM) have been shown to experience high levels of stigma and discrimination, increasing their vulnerability to negative health and other outcomes. This paper examines the relationship between criminalization of same-sex behavior and experiences of human rights abuses by MSM. It compares the extent to which MSM in peri-urban Cape Town experience human rights abuses with that of MSM in Gaborone, Botswana; Blantyre and Lilongwe, Malawi; and Windhoek, Namibia. In 2008, 737 MSM participated in a cross-sectional study using a structured survey collecting data regarding demographics, human rights, HIV status, and risk behavior. Participants accrued in each site were compared using bivariate and multivariate logistic regression. Encouragingly, the results indicate MSM in Cape Town were more likely to disclose their sexual orientation to family or healthcare workers and less likely to be blackmailed or feel afraid in their communities than MSM in Botswana, Malawi, or Namibia. However, South African MSM were not statistically significantly less likely experience a human rights abuse than their peers in cities in other study countries, showing that while legal protections may reduce experiences of certain abuses, legislative changes alone are insufficient for protecting MSM. A comprehensive approach with interventions at multiple levels in multiple sectors is needed to create the legal and social change necessary to address attitudes, discrimination, and violence affecting MSM. PMID:26764467

  19. Parenting experiences of couples living with human immunodeficiency virus: A qualitative study from rural Southern Malawi

    PubMed Central

    Gombachika, Belinda Chimphamba; Sundby, Johanne; Chirwa, Ellen; Malata, Address

    2014-01-01

    Abstract The advent of antiretroviral therapy (ART) has allowed couples living with human immunodeficiency virus (HIV) to live longer and healthier lives. The reduction in the mother-to-child transmission of HIV has encouraged some people living with HIV (PLWH) to have children. However, little is known about the parenting experiences of couples living with HIV (CLWH). The aim of this qualitative study was to explore and describe parenting experiences of seroconcordant couples who have a child while living with HIV in Malawi. Data were collected using in-depth interviews with 14 couples purposively sampled in matrilineal Chiradzulu and patrilineal Chikhwawa communities from July to December 2010. The research findings shows that irrespective of kinship organization, economic hardships, food insecurity, gender-specific role expectations and conflicting information from health institutions and media about sources of support underpin their parenting roles. In addition, male spouses are directly involved in household activities, childcare and child feeding decisions, challenging the existing stereotyped gender norms. In the absence of widow inheritance, widows from patrilineal communities are not receiving the expected support from the deceased husband relatives. Finally, the study has shown that CLWH are able to find solutions for the challenges they encounter. Contrary to existing belief that such who have children depend solely on public aid. Such claims without proper knowledge of local social cultural contexts, may contribute to stigmatizing CLWH who continue to have children. The study is also relevant to PLWH who, although not parents themselves, are confronted with a situation where they have to accept responsibility for raising children from their kin. We suggest the longer-term vision for ART wide access in Malawi to be broadened beyond provision of ART to incorporate social and economic interventions that support the rebuilding of CLWH social and economic

  20. Hydrochemical characteristics of rural community groundwater supply in Blantyre, southern Malawi

    NASA Astrophysics Data System (ADS)

    Mapoma, Harold Wilson Tumwitike; Xie, Xianjun; Zhang, Liping; Nyirenda, Mathews Tananga; Maliro, Albert; Chimutu, Darlington

    2016-02-01

    The purpose of this research was to characterize the quality of groundwater for drinking and irrigation in Blantyre, Malawi as well as identify some geochemical processes governing mineralization of major and some minor elements. The aquifer studied is part of the extensive crystalline basement complex. The suitability and classification involved confirmatory analysis of the results with World Health Organization and Malawi Standards Board groundwater guideline values. The water samples were analyzed for major descriptors (pH, Temperature, turbidity, major ions, total dissolved solids and electrical conductivity (EC), using standard methods. Besides, arsenic, iron and fluoride were analyzed as well. Multivariate statistics (especially Hierarchical Cluster Analysis and Factor Analysis), hydrographical methods (i.e. Piper diagram) and geochemical modeling programs (AquaChem and PHREEQC) were used to characterize the quality and explain the sources and evolution of groundwater. Suitability of groundwater for irrigation was assessed using Wilcox method which identified BH01, BH16 and BH21 as high salinity areas. Incidentally, the three boreholes had relatively higher sulfate and nitrate concentrations than the rest. Nevertheless, the groundwater was found to be within acceptable limits for drinking quality except elevated concentrations of nitrate, fluoride and iron in some boreholes compared with WHO standards, despite meeting the national standards. Borehole BH01, BH02, BH07, BH13 and BH18 exhibited nitrate concentrations greater than national standards (45 mg/L) an indication of groundwater contamination. Furthermore, the groundwater is slightly acidic to slightly above neutral with total dissolved solids less than 500 mg/l. Generally, groundwater was undersaturated with respect to both calcite and dolomite while oversaturated with respect to halite, goethite and hematite. Silicate and carbonate weathering were identified as main mineral sources for major ions in

  1. Parenting experiences of couples living with human immunodeficiency virus: a qualitative study from rural Southern Malawi.

    PubMed

    Gombachika, Belinda Chimphamba; Sundby, Johanne; Chirwa, Ellen; Malata, Address

    2014-01-01

    The advent of antiretroviral therapy (ART) has allowed couples living with human immunodeficiency virus (HIV) to live longer and healthier lives. The reduction in the mother-to-child transmission of HIV has encouraged some people living with HIV (PLWH) to have children. However, little is known about the parenting experiences of couples living with HIV (CLWH). The aim of this qualitative study was to explore and describe parenting experiences of seroconcordant couples who have a child while living with HIV in Malawi. Data were collected using in-depth interviews with 14 couples purposively sampled in matrilineal Chiradzulu and patrilineal Chikhwawa communities from July to December 2010. The research findings shows that irrespective of kinship organization, economic hardships, food insecurity, gender-specific role expectations and conflicting information from health institutions and media about sources of support underpin their parenting roles. In addition, male spouses are directly involved in household activities, childcare and child feeding decisions, challenging the existing stereotyped gender norms. In the absence of widow inheritance, widows from patrilineal communities are not receiving the expected support from the deceased husband relatives. Finally, the study has shown that CLWH are able to find solutions for the challenges they encounter. Contrary to existing belief that such who have children depend solely on public aid. Such claims without proper knowledge of local social cultural contexts, may contribute to stigmatizing CLWH who continue to have children. The study is also relevant to PLWH who, although not parents themselves, are confronted with a situation where they have to accept responsibility for raising children from their kin. We suggest the longer-term vision for ART wide access in Malawi to be broadened beyond provision of ART to incorporate social and economic interventions that support the rebuilding of CLWH social and economic lives. The

  2. Applications of the IRI in Southern Africa

    NASA Astrophysics Data System (ADS)

    Coetzee, P. J.

    2004-01-01

    The IRI forms the basis of the Single Site Location Direction Finding networks of the South African Defence Force as well as theNational Intelligence Agency. It is also used in "Path Analysis" applications where the possible transmitter coverage is calculated. Another application of the IRI is in HF frequency predictions, especially for the South African Defence Force involved in peace keeping duties in Africa. The IRI is either used independently or in conjunction with vertical ionosondes. In the latter case the scaled F2 peak parameters (foF2, hmF2) are used as inputs to the IRI. The IRI thus gets "calibrated" to extend the area covered by the ionosonde(s). The IRI has proved to be a very important tool in South Africa and Africa in the fight against crime, drug trafficking, political instability and maintaining the peace in potentially unstable countries.

  3. Transport of Biomass Burning Emissions from Southern Africa

    NASA Technical Reports Server (NTRS)

    Sinha, Parikhit; Jaegle,Lyatt; Hobbs, Peter V.; Liang, Qing

    2004-01-01

    The transport of biomass burning emissions from southern Africa to the neighboring Atlantic and Indian Oceans during the dry season (May-October) of 2000 is characterized using ground, ozonesonde, and aircraft measurements of carbon monoxide (CO) and ozone (O3) in and around southern Africa, together with the GEOS-CHEM global model of tropospheric chemistry. The model shows a positive bias of approximately 20% for CO and a negative bias of approximately 10-25% for O3 at oceanic sites downwind of fire emissions. Near areas of active fire emissions the model shows a negative bias of approximately 60% and approximately 30% for CO and O3, respectively, likely due to the coarse spatial (2 deg. x 2.5 deg.) and temporal (monthly) resolution of the model compared to that of active fires. On average, from 1994 to 2000, approximately 60 Tg of carbon monoxide (CO) from biomass burning in southern Africa was transported eastward to the Indian Ocean across the latitude band 0 deg. -60 S during the 6 months of the dry season. Over the same time period, approximately 40 Tg of CO from southern African biomass burning was transported westward to the Atlantic Ocean over the latitudes 0 deg. -20 S during the 6-month dry season, but most of that amount was transported back eastward over higher latitudes to the south (21 deg. -60 S). Eastward transport of biomass burning emissions from southern Africa enhances CO concentrations by approximately 4- 13 ppbv per month over the southern subtropical Indian Ocean during the dry season, with peak enhancements in September. Carbon monoxide from southern African and South American biomass burning is seen in the model simulations as far away as Australia, contributing approximately 8 ppbv and approximately 12-15 ppbv CO, respectively, and thus explaining the approximately 20- 25 ppbv observed enhancement of CO over Melbourne in mid-September 2000.

  4. Creating Cultural Competence: An Outreach Immersion Experience in Southern Africa

    ERIC Educational Resources Information Center

    West-Olatunji, Cirecie; Goodman, Rachael D.; Mehta, Sejal; Templeton, Laura

    2011-01-01

    With disasters on the rise, counselors need to increase their cultural awareness, knowledge, and skills to work with affected communities. This study reports outcomes of a four-week immersion experience in southern Africa with six counselor-trainees. Data sources for this qualitative study were: daily journals and demographic forms. Outcomes…

  5. Primary School Literacy in Southern Africa: African Perspectives

    ERIC Educational Resources Information Center

    Perry, Kristen H.

    2008-01-01

    This research review examines trends in recent scholarship concerning primary school literacy instruction in Southern Africa. Past scholarship, particularly that which originated from western researchers, focused on technical or structural issues facing literacy instruction in the region, such as language of instruction, school conditions,…

  6. Environmental Education Research in Southern Africa: Dilemmas of Interpretation

    ERIC Educational Resources Information Center

    Gough, Annette; Gough, Noel

    2004-01-01

    These multiple framings of our reflections on environmental education research in southern Africa are written as dilemmas of interpretation that aim to disrupt any temptation to generalise or essentialise its qualities and characteristics. Recognising that research is a textual practice, we use J. M. Coetzee's portrayal of the dilemmas faced by…

  7. Seismic Hazard Implication of the Seismotectonics of southern Africa

    NASA Astrophysics Data System (ADS)

    Midzi, Vunganai; Mulabisana, Thifelimbilu; Manzunzu, Brassnavy

    2014-05-01

    The work presented in this report / presentation was prepared as part of the requirements for the SIDA/IGCP Project 601 titled "Seismotectonics and Seismic Hazards in Africa" as well as part of the seismic source characterisation of the GEM-Africa Seismic hazard study. An effort was made to compile information necessary to prepare a seismotectonic map of Africa which can then be used in carrying out a seismic hazard assessment of the continent or locations within the continent. Information on major faults, fault plane solutions, geophysical data as well as stress data has so far been collected and included in a database for the southern Africa region. Reports published by several experts contributed much to the collected information. The seismicity data used are part of the earthquake catalogue being prepared for the GEM-Africa project, which includes historical and instrumental records as collected from various sources. An effort has been made to characterise the identified major faults and through further analysis investigate their possible impact on the seismic hazard of southern Africa.

  8. Phytoliths Used to Investigate the Effects of the Indonesian Mount Toba Super-Eruption (~75 kyr) in East Africa: A Subdecadal Record from Lake Malawi

    NASA Astrophysics Data System (ADS)

    Yost, C. L.; Cohen, A. S.

    2014-12-01

    The recent discovery of cryptotephra visually and chemically matched to the Youngest Toba Tuff (YTT, 75.0 ± 0.9 kyr) in Lake Malawi drill core sediments has spurred renewed interest in this period of time in East Africa. The YTT is the most recent and largest of the four Mount Toba eruptions, and is the only super-eruption to have taken place during the Quaternary. The timing of the YTT approximately coincides with a hypothesized human genetic bottleneck. Several climate models have proposed an episode of global cooling following the YTT; however, the magnitude and duration of the cooling is much debated, ranging from just a few degrees of cooling to a state of volcanic winter. Cored sediments from Lake Malawi provide an excellent record of local variability in the lake's watershed that may be linked to specific climatic events. To investigate the possible effects of the YTT in East Africa, we continuously sampled Lake Malawi drill core 2A-10H-2 at 2-4 mm (~6 yr) intervals above and below the first occurrence of the YTT. Poaceae phytoliths were grouped into plant functional types (C3, C4, xerophytic, mesophytic, arboreal, etc.), revealing mostly subtle changes in terrestrial vegetation over the ~400 yr time period examined. Abrupt increases in concentration values for phytoliths derived from riverine Podostemaceae plants appear to signal increased discharge from rivers draining the surrounding uplands. Perhaps most significant is the increasing trend in burned phytoliths and decreasing trend in tree phytoliths post-YTT. Although there appears to be a very weak cooling signal synchronous with the YTT, the most abrupt terrestrial vegetation changes appear to be better correlated with the deposition of a slightly older cryptotephra horizon derived from the local Rungwe Volcanic Province. A potential complication with this record is the existence of a turbidite pre-YTT that encompasses the Rungwe horizon.

  9. 'It was caused by the carelessness of the parents': cultural models of child malnutrition in southern Malawi.

    PubMed

    Flax, Valerie L

    2015-01-01

    Parents' conceptions of child growth, health and malnutrition are culturally bound, making information about local understandings of malnutrition and its causes necessary for designing effective nutrition programmes. This study used ethnographic methods to elucidate cultural models of child care and malnutrition among the Yao of southern Malawi. Data were collected in six rural villages from 28 key informant interviews with village chiefs and traditional healers among others and 18 focus group discussions with parents and grandmothers of young children. For the Yao, lack of parental care is a key cause of poor child health and can lead to thinness (kunyililika) or swelling (kuimbangana). Parents are said to be careless if they are not attentive to the child's needs, are unable to provide adequate quality or quantity of food, or fail to follow sexual abstinence rules. Maintaining abstinence protects the family and failure to do so causes the transfer of 'heat' from a sexually active parent to a 'cold' child and results in child health problems, including signs and symptoms of malnutrition. These findings indicate that the Yao understanding of care is much broader than the concept of care during feeding described in the nutrition literature. In addition, the Yao note the importance of several key feeding practices supported by international agencies and understand the influence of illness on child nutritional status. These congruencies with the public health frame should be used together with information about the cultural context to design more socially and emotionally relevant care and nutrition programmes among the Yao. PMID:23941316

  10. Population genetic structure, linkage disequilibrium and effective population size of conserved and extensively raised village chicken populations of Southern Africa

    PubMed Central

    Khanyile, Khulekani S.; Dzomba, Edgar F.; Muchadeyi, Farai C.

    2015-01-01

    Extensively raised village chickens are considered a valuable source of biodiversity, with genetic variability developed over thousands of years that ought to be characterized and utilized. Surveys that can reveal a population's genetic structure and provide an insight into its demographic history will give valuable information that can be used to manage and conserve important indigenous animal genetic resources. This study reports population diversity and structure, linkage disequilibrium and effective population sizes of Southern African village chickens and conservation flocks from South Africa. DNA samples from 312 chickens from South African village and conservation flocks (n = 146), Malawi (n = 30) and Zimbabwe (n = 136) were genotyped using the Illumina iSelect chicken SNP60K BeadChip. Population genetic structure analysis distinguished the four conservation flocks from the village chicken populations. Of the four flocks, the Ovambo clustered closer to the village chickens particularly those sampled from South Africa. Clustering of the village chickens followed a geographic gradient whereby South African chickens were closer to those from Zimbabwe than to chickens from Malawi. Different conservation flocks seemed to have maintained different components of the ancestral genomes with a higher proportion of village chicken diversity found in the Ovambo population. Overall population LD averaged over chromosomes ranged from 0.03 ± 0.07 to 0.58 ± 0.41 and averaged 0.15 ± 0.16. Higher LD, ranging from 0.29 to 0.36, was observed between SNP markers that were less than 10 kb apart in the conservation flocks. LD in the conservation flocks steadily decreased to 0.15 (PK) and 0.24 (VD) at SNP marker interval of 500 kb. Genomewide LD decay in the village chickens from Malawi, Zimbabwe and South Africa followed a similar trend as the conservation flocks although the mean LD values for the investigated SNP intervals were lower. The results suggest low effective

  11. The decision to vaccinate a child: an economic perspective from southern Malawi.

    PubMed

    Holte, Jon H; Mæstad, Ottar; Jani, Jagrati V

    2012-07-01

    The dynamics of childhood vaccination uptake in developing countries are unclear. Numerous studies document the relationship between vaccination coverage and access, socio economic and demographic factors. However, there is less knowledge about the relationship between vaccination coverage and carers' motivation and willingness to seek childhood vaccinations. The aim of this paper is to introduce a framework for studying demand for childhood vaccination and to examine the coherence between theoretical predictions and empirical findings in a rural area in Malawi. We interviewed 635 carers with children aged 18-59 months. About 96 percent of the respondents reported to have fully vaccinated their youngest eligible child for all routine vaccinations scheduled in the Expanded Program on Immunization. This paper concludes that easy access to vaccination services cannot explain why demand is high. Many carers had to travel long distances to reach vaccination delivery points and a considerable share of the respondents scored waiting and travelling time as long. Results from the present study, in combination with theoretical predictions, suggest that a high level of trust in distributors of information and vaccines may be an essential explanatory factor for why carers seek immunization for their children, even in the presence of considerable costs. Trust may be an important explanatory factor as it can be seen to generate positive perceived benefits. PMID:22571892

  12. Climatology of Aerosol Optical Properties in Southern Africa

    NASA Technical Reports Server (NTRS)

    Queface, Antonio J.; Piketh, Stuart J.; Eck, Thomas F.; Tsay, Si-Chee

    2011-01-01

    A thorough regionally dependent understanding of optical properties of aerosols and their spatial and temporal distribution is required before we can accurately evaluate aerosol effects in the climate system. Long term measurements of aerosol optical depth, Angstrom exponent and retrieved single scattering albedo and size distribution, were analyzed and compiled into an aerosol optical properties climatology for southern Africa. Monitoring of aerosol parameters have been made by the AERONET program since the middle of the last decade in southern Africa. This valuable information provided an opportunity for understanding how aerosols of different types influence the regional radiation budget. Two long term sites, Mongu in Zambia and Skukuza in South Africa formed the core sources of data in this study. Results show that seasonal variation of aerosol optical thicknesses at 500 nm in southern Africa are characterized by low seasonal multi-month mean values (0.11 to 0.17) from December to May, medium values (0.20 to 0.27) between June and August, and high to very high values (0.30 to 0.46) during September to November. The spatial distribution of aerosol loadings shows that the north has high magnitudes than the south in the biomass burning season and the opposite in none biomass burning season. From the present aerosol data, no long term discernable trends are observable in aerosol concentrations in this region. This study also reveals that biomass burning aerosols contribute the bulk of the aerosol loading in August-October. Therefore if biomass burning could be controlled, southern Africa will experience a significant reduction in total atmospheric aerosol loading. In addition to that, aerosol volume size distribution is characterized by low concentrations in the non biomass burning period and well balanced particle size contributions of both coarse and fine modes. In contrast high concentrations are characteristic of biomass burning period, combined with

  13. Complex Patterns of Genomic Admixture within Southern Africa

    PubMed Central

    Petersen, Desiree C.; Libiger, Ondrej; Tindall, Elizabeth A.; Hardie, Rae-Anne; Hannick, Linda I.; Glashoff, Richard H.; Mukerji, Mitali; Fernandez, Pedro; Haacke, Wilfrid; Schork, Nicholas J.; Hayes, Vanessa M.

    2013-01-01

    Within-population genetic diversity is greatest within Africa, while between-population genetic diversity is directly proportional to geographic distance. The most divergent contemporary human populations include the click-speaking forager peoples of southern Africa, broadly defined as Khoesan. Both intra- (Bantu expansion) and inter-continental migration (European-driven colonization) have resulted in complex patterns of admixture between ancient geographically isolated Khoesan and more recently diverged populations. Using gender-specific analysis and almost 1 million autosomal markers, we determine the significance of estimated ancestral contributions that have shaped five contemporary southern African populations in a cohort of 103 individuals. Limited by lack of available data for homogenous Khoesan representation, we identify the Ju/'hoan (n = 19) as a distinct early diverging human lineage with little to no significant non-Khoesan contribution. In contrast to the Ju/'hoan, we identify ancient signatures of Khoesan and Bantu unions resulting in significant Khoesan- and Bantu-derived contributions to the Southern Bantu amaXhosa (n = 15) and Khoesan !Xun (n = 14), respectively. Our data further suggests that contemporary !Xun represent distinct Khoesan prehistories. Khoesan assimilation with European settlement at the most southern tip of Africa resulted in significant ancestral Khoesan contributions to the Coloured (n = 25) and Baster (n = 30) populations. The latter populations were further impacted by 170 years of East Indian slave trade and intra-continental migrations resulting in a complex pattern of genetic variation (admixture). The populations of southern Africa provide a unique opportunity to investigate the genomic variability from some of the oldest human lineages to the implications of complex admixture patterns including ancient and recently diverged human lineages. PMID:23516368

  14. Canine rabies ecology in southern Africa.

    PubMed

    Bingham, John

    2005-09-01

    Rabies is a widespread disease in African domestic dogs and certain wild canine populations. Canine rabies became established in Africa during the 20th century, coinciding with ecologic changes that favored its emergence in canids. I present a conceptual and terminologic framework for understanding rabies ecology in African canids. The framework is underpinned by 2 distinct concepts: maintenance and persistence. Maintenance encompasses the notion of indefinite transmission of infection within a local population and depends on an average transmission ratio > or =1. Maintenance in all local populations is inherently unstable, and the disease frequently becomes extinct. Persistence, the notion of long-term continuity, depends on the presence of rabies in > or =1 local population within the canine metapopulation at any time. The implications for understanding rabies ecology and control are reviewed, as are previous studies on rabies ecology in African canids. PMID:16229759

  15. Proposed new International Space Geodesy Facility for southern Africa

    NASA Astrophysics Data System (ADS)

    Combrinck, W. L.; Combrink, A. Z. A.

    The National Research Foundation (NRF) of South Africa is planning to construct a new International Space Geodesy Facility to serve the southern African region and international science community. The station will host satellite and lunar laser ranging equipment, a GPS network, geodetic VLBI equipment, as well as geophysical instrumentation. One of the many objectives of the new facility is capacity building in the Southern African Development Community (SADC) region. This will ensure active and high-level participation of universities and institutes throughout SADC in collaboration with the international community. An overview of this project, including an initial site survey, as well as scientific objectives will be discussed.

  16. Factors Driving the HIV Epidemic in Southern Africa.

    PubMed

    McKinnon, Lyle R; Karim, Quarraisha Abdool

    2016-06-01

    The HIV pandemic has disproportionately impacted sub-Saharan Africa and Southern Africa in particular. The concurrent presence of overlapping epidemic drivers likely underpins how and why the HIV epidemic is so explosive in this region, with implications for understanding approaches to reduce transmission. In this review, we discuss the relative contribution and interaction between epidemic drivers in the Southern African context, including factors both distally and proximally associated with the likelihood and degree of exposure to HIV and factors that increase the probability of transmission when exposure occurs. In particular, we focus on young women as a key population in need of HIV prevention and highlight factors that increase their risk on several levels. PMID:27137200

  17. Maternal Death Surveillance and Response in East and Southern Africa.

    PubMed

    Scott, Heather; Dairo, Akinyele

    2015-10-01

    Maternal death surveillance and response (MDSR) is one of several low cost, high impact strategies to reduce maternal mortality. This initiative is supported in eastern and southern Africa by the United Nations Population Fund (UNFPA) and other partners. Currently, South Africa is the leading country in the institutionalization of MDSR through the Confidential Enquiry into Maternal Deaths (CEMD). With the support of UNFPA and other partners, at least 15 countries in the region have introduced MDSR into maternal and newborn health care programs. The report from the knowledge-sharing meeting and the findings of the evaluation of the South African MDSR show that MDSR is still not at an optimal level in most countries in sub-Saharan Africa, despite the efforts of national authorities and support from a number of development partners. Additional work is required on the part of national authorities, communities, and development organizations, and the challenges being faced were highlighted at the knowledge-sharing meeting. PMID:26606709

  18. El Niño–Southern Oscillation diversity and Southern Africa teleconnections during Austral Summer

    USGS Publications Warehouse

    Hoell, Andrew; Funk, Christopher C.; Magadzire, Tamuka; Zinke, Jens; Husak, Gregory J.

    2014-01-01

    A wide range of sea surface temperature (SST) expressions have been observed during the El Niño–Southern Oscillation events of 1950–2010, which have occurred simultaneously with different global atmospheric circulations. This study examines the atmospheric circulation and precipitation during December–March 1950–2010 over the African Continent south of 15∘S, a region hereafter known as Southern Africa, associated with eight tropical Pacific SST expressions characteristic of El Niño and La Niña events. The self-organizing map method along with a statistical distinguishability test was used to isolate the SST expressions of El Niño and La Niña. The seasonal precipitation forcing over Southern Africa associated with the eight SST expressions was investigated in terms of the horizontal winds, moisture budget and vertical motion. El Niño events, with warm SST across the east and central Pacific Ocean and warmer than average SST over the Indian Ocean, are associated with precipitation reductions over Southern Africa. The regional precipitation reductions are forced primarily by large-scale mid-tropospheric subsidence associated with anticyclonic circulation in the upper troposphere. El Niño events with cooler than average SST over the Indian Ocean are associated with precipitation increases over Southern Africa associated with lower tropospheric cyclonic circulation and mid-tropospheric ascent. La Niña events, with cool SST anomalies over the central Pacific and warm SST over the west Pacific and Indian Ocean, are associated with precipitation increases over Southern Africa. The regional precipitation increases are forced primarily by lower tropospheric cyclonic circulation, resulting in mid-tropospheric ascent and an increased flux of moisture into the region.

  19. Tracing pastoralist migrations to southern Africa with lactase persistence alleles.

    PubMed

    Macholdt, Enrico; Lede, Vera; Barbieri, Chiara; Mpoloka, Sununguko W; Chen, Hua; Slatkin, Montgomery; Pakendorf, Brigitte; Stoneking, Mark

    2014-04-14

    Although southern African Khoisan populations are often assumed to have remained largely isolated during prehistory, there is growing evidence for a migration of pastoralists from eastern Africa some 2,000 years ago, prior to the arrival of Bantu-speaking populations in southern Africa. Eastern Africa harbors distinctive lactase persistence (LP) alleles, and therefore LP alleles in southern African populations may be derived from this eastern African pastoralist migration. We sequenced the lactase enhancer region in 457 individuals from 18 Khoisan and seven Bantu-speaking groups from Botswana, Namibia, and Zambia and additionally genotyped four short tandem repeat (STR) loci that flank the lactase enhancer region. We found nine single-nucleotide polymorphisms, of which the most frequent is -14010(∗)C, which was previously found to be associated with LP in Kenya and Tanzania and to exhibit a strong signal of positive selection. This allele occurs in significantly higher frequency in pastoralist groups and in Khoe-speaking groups in our study, supporting the hypothesis of a migration of eastern African pastoralists that was primarily associated with Khoe speakers. Moreover, we find a signal of ongoing positive selection in all three pastoralist groups in our study, as well as (surprisingly) in two foraging groups. PMID:24704073

  20. Climate and southern Africa's water-energy-food nexus

    NASA Astrophysics Data System (ADS)

    Conway, Declan; van Garderen, Emma Archer; Deryng, Delphine; Dorling, Steve; Krueger, Tobias; Landman, Willem; Lankford, Bruce; Lebek, Karen; Osborn, Tim; Ringler, Claudia; Thurlow, James; Zhu, Tingju; Dalin, Carole

    2015-09-01

    In southern Africa, the connections between climate and the water-energy-food nexus are strong. Physical and socioeconomic exposure to climate is high in many areas and in crucial economic sectors. Spatial interdependence is also high, driven, for example, by the regional extent of many climate anomalies and river basins and aquifers that span national boundaries. There is now strong evidence of the effects of individual climate anomalies, but associations between national rainfall and gross domestic product and crop production remain relatively weak. The majority of climate models project decreases in annual precipitation for southern Africa, typically by as much as 20% by the 2080s. Impact models suggest these changes would propagate into reduced water availability and crop yields. Recognition of spatial and sectoral interdependencies should inform policies, institutions and investments for enhancing water, energy and food security. Three key political and economic instruments could be strengthened for this purpose: the Southern African Development Community, the Southern African Power Pool and trade of agricultural products amounting to significant transfers of embedded water.

  1. Land Cover Mapping for the Development of Green House Gas (GHG) Inventories in the Eastern and Southern Africa Region

    NASA Astrophysics Data System (ADS)

    Wakhayanga, J. A.; Oduor, P.; Korme, T.; Farah, H.; Limaye, A. S.; Irwin, D.; Artis, G.

    2014-12-01

    Anthropogenic activities are responsible for the largest share of green house gas (GHG) emissions. Research has shown that greenhouse gases cause radioactive forcing in the stratosphere, leading to ozone depletion. Different land cover types act as sources or sinks of carbon dioxide (CO2), the most dominant GHG.Under the oversight of the United Nations Framework Convention on Climate Change (UNFCCC) the Eastern and Southern Africa (ESA) region countries are developing Sustainable National GHG Inventory Management Systems. While the countries in the ESA region are making substantial progress in setting up GHG inventories, there remains significant constraints in the development of quality and sustainable National GHG Inventory Systems. For instance, there are fundamental challenges in capacity building and technology transfer, which can affect timely and consistent reporting on the land use, land-use change and forestry (LULUCF) component of the GHG inventory development. SERVIR Eastern and Southern Africa is a partnership project between the National Aeronautics and Space Administration (NASA) and the Regional Center for Mapping of Resources for Development (RCMRD), an intergovernmental organization in Africa, with 21 member states in the ESA region. With support from the United States Agency for International Development (USAID), SERVIR ESA is implementing the GHG Project in 9 countries. The main deliverables of the project are land cover maps for the years 2000 and 2010 (also 1990 for Malawi and Rwanda), and related technical reports, as well as technical training in land cover mapping using replicable methodologies. Landsat imagery which is freely available forms the main component of earth observation input data, in addition to ancillary data collected from each country. Supervised classification using maximum likelihood algorithm is applied to the Landsat images. The work is completed for the initial 6 countries (Malawi, Zambia, Rwanda, Tanzania, Botswana, and

  2. Notes on southern Africa Jerusalem crickets (Orthoptera: Stenopelmatidae: Sia).

    PubMed

    Weissman, David B; Bazelet, Corinna S

    2013-01-01

    The Old World Jerusalem cricket (JC) subfamily Siinae contains one genus, Sia, with two subgenera: Sia (Sia) with two fully winged species from southeast Asia, and Sia (Maxentius) with four wingless species from southern Africa. Because there is a dearth of published data about the behavior and biology of these insects, we present new field and laboratory research on southern African Sia (Maxentius), gather museum and literature information, and present guidelines for collecting and rearing specimens. While we make no taxonomic decisions, this review should be useful for future studies, including a needed taxonomic revision. We also compare results from these southern African JCs with recent investigations on related New World taxa, where fascinating biological traits and extensive cryptic biodiversity have been uncovered. DNA analysis reveals that these Old and New World JCs are polyphyletic. PMID:24758791

  3. 3.5 billion years of reshaped Moho, southern Africa

    NASA Astrophysics Data System (ADS)

    Stankiewicz, Jacek; de Wit, Maarten

    2013-12-01

    According to some previous studies, Archean continental crust is, on global average, apparently thinner than Proterozoic crust. Subsequently, the validity of this statement has been questioned. To provide an additional perspective on this issue, we present analyses of Moho signatures derived from recent seismic data along swaths 2000 km in length across southern Africa and its flanking ocean. The imaged crust has a near continuous age range between ca. 0.1 and 3.7 billion years, and the seismic data allow direct comparison of Moho depths between adjacent Archean, Proterozoic and Phanerozoic crust. We find no simple secular change in depth to Moho over this time period. In contrast, there is significant variation in depth to Moho beneath both Archean and Proterozoic crust; Archean crust of southern Africa displays as much crustal diversity in thickness as the adjacent Proterozoic crust. The Moho beneath all crustal provinces that we have analysed has been severely altered by tectono-metamorphic and igneous processes, in many cases more than once, and cannot provide unequivocal data for geodynamic models dealing with secular changes in continental crust formation. These results and conclusions are similar to those documented along ca. 2000 km swaths across the Canadian Shield recorded by Lithoprobe. Tying the age and character of the Precambrian crust of southern Africa to their depth diversities is clearly related to manifold processes of tectono-thermal ‘surgery’ subsequent to their origin, the details of which are still to be resolved, as they are in most Precambrian terranes. Reconstructing pristine Moho of the early Earth therefore remains a formidable challenge. In South Africa, better knowledge of ‘fossilised’ Archean crustal sections ‘turned-on-edge’, such as at the Vredefort impact crater (for the continental crust), and from the Barberton greenstone belt (for oceanic crust) is needed to characterize potential pristine Archean Moho transitions.

  4. Multi-Country Analysis of Treatment Costs for HIV/AIDS (MATCH): Facility-Level ART Unit Cost Analysis in Ethiopia, Malawi, Rwanda, South Africa and Zambia

    PubMed Central

    Tagar, Elya; Sundaram, Maaya; Condliffe, Kate; Matatiyo, Blackson; Chimbwandira, Frank; Chilima, Ben; Mwanamanga, Robert; Moyo, Crispin; Chitah, Bona Mukosha; Nyemazi, Jean Pierre; Assefa, Yibeltal; Pillay, Yogan; Mayer, Sam; Shear, Lauren; Dain, Mary; Hurley, Raphael; Kumar, Ritu; McCarthy, Thomas; Batra, Parul; Gwinnell, Dan; Diamond, Samantha; Over, Mead

    2014-01-01

    Background Today's uncertain HIV funding landscape threatens to slow progress towards treatment goals. Understanding the costs of antiretroviral therapy (ART) will be essential for governments to make informed policy decisions about the pace of scale-up under the 2013 WHO HIV Treatment Guidelines, which increase the number of people eligible for treatment from 17.6 million to 28.6 million. The study presented here is one of the largest of its kind and the first to describe the facility-level cost of ART in a random sample of facilities in Ethiopia, Malawi, Rwanda, South Africa and Zambia. Methods & Findings In 2010–2011, comprehensive data on one year of facility-level ART costs and patient outcomes were collected from 161 facilities, selected using stratified random sampling. Overall, facility-level ART costs were significantly lower than expected in four of the five countries, with a simple average of $208 per patient-year (ppy) across Ethiopia, Malawi, Rwanda and Zambia. Costs were higher in South Africa, at $682 ppy. This included medications, laboratory services, direct and indirect personnel, patient support, equipment and administrative services. Facilities demonstrated the ability to retain patients alive and on treatment at these costs, although outcomes for established patients (2–8% annual loss to follow-up or death) were better than outcomes for new patients in their first year of ART (77–95% alive and on treatment). Conclusions This study illustrated that the facility-level costs of ART are lower than previously understood in these five countries. While limitations must be considered, and costs will vary across countries, this suggests that expanded treatment coverage may be affordable. Further research is needed to understand investment costs of treatment scale-up, non-facility costs and opportunities for more efficient resource allocation. PMID:25389777

  5. Shear Wave Splitting Across Eastern, Western and Southern Africa

    NASA Astrophysics Data System (ADS)

    Nyblade, A.; Ramirez, C.; Bagley, B. C.; Mulibo, G. D.; Tugume, F.; Wysession, M. E.; Wiens, D. A.

    2014-12-01

    The expansion of the AfricaArray network across eastern, western and southern Africa, in conjunction with seismic data from many PASSCAL deployments over the past 20 years, is helping to fill in major gaps in the global coverage of shear wave splitting measurements. New results from stations in Ghana, Nigeria, Mozambique, Botswana, Angola, Namibia and South Africa are presented in this study that when combined with previously published measurements help to map the pattern of seismic anisotropy over much of the African continent. A general pattern of fast polarization directions, characterized by NE orientations, is found, and superimposed on this subcontinental-scale pattern is local and regional variability, most notably around the Archean Tanzania craton in eastern Africa. The subcontinental-scale pattern, as well as local and regional variations in this pattern, are interpreted in terms of large-scale mantle flow from the African Superplume, fossil anisotropy in the lithosphere, and shape anisotropy in magmatic regions of the East African rift system.

  6. Otavipithecus namibiensis, first Miocene hominoid from southern Africa.

    PubMed

    Conroy, G C; Pickford, M; Senut, B; Van Couvering, J; Mein, P

    1992-03-12

    We report here the discovery of a Miocene hominoid from Berg Aukas, Namibia, the first known from the African continent south of equatorial East Africa. This represents a major range extension of Miocene Hominoidea in Africa to latitude 20 degrees S. The holotype, a right mandibular corpus preserving the crowns of the P4-M3, partial crown and root of the P3, partial root of the canine, alveoli for all four incisors, and partial alveolus for the left canine, was found during paleontological explorations of karst-fill breccias in the Otavi region of northern Namibia. The mandible has unique characteristics that differentiate it from other middle Miocene hominoids of Africa and Eurasia and represents the only fossil evidence documenting a pre-australopithecine stage of hominoid evolution in southern Africa. Faunal analyses indicate that the breccia block containing the specimen accumulated during the latter part of the middle Miocene, about 13 +/- 1 Myr. Fauna from other breccia blocks at Berg Aukas are of diverse ages, including the earlier part of the middle Miocene, the upper Miocene, Plio-Pleistocene and Holocene. PMID:1545864

  7. Pre-exposure prophylaxis in Southern Africa: feasible or not?

    PubMed Central

    Venter, Willem Daniel François; Cowan, Frances; Black, Vivian; Rebe, Kevin; Bekker, Linda-Gail

    2015-01-01

    Introduction Southern and Eastern Africa bear the brunt of the AIDS epidemic, and current prevention interventions remain inadequate. Antiretroviral-based pre-exposure prophylaxis (PrEP) is gaining momentum as an effective prevention intervention. Discussion Discussions have been started on how this strategy could be employed in Africa such that the populations most in need can be reached urgently for the greatest impact. This requires the selection of specific risk groups and service environments in which PrEP can be distributed safely and cost effectively while being mindful of any ethical issues. Conclusions Given the need for an integrated public health approach to this, a number of potential populations and opportunities for PrEP distribution exist and are discussed in this commentary. PMID:26198344

  8. Southern Africa Validation of NASA's Earth Observing System (SAVE EOS)

    NASA Technical Reports Server (NTRS)

    Privette, Jeffrey L.

    2000-01-01

    Southern Africa Validation of EOS (SAVE) is 4-year, multidisciplinary effort to validate operational and experimental products from Terra-the flagship satellite of NASA's Earth Observing System (EOS). At test sites from Zambia to South Africa, we are measuring soil, vegetation and atmospheric parameters over a range of ecosystems for comparison with products from Terra, Landsat 7, AVHRR and SeaWiFS. The data are also employed to parameterize and improve vegetation process models. Fixed-point and mobile "transect" sampling are used to collect the ground data. These are extrapolated over larger areas with fine-resolution multispectral imagery. We describe the sites, infrastructure, and measurement strategies developed underSAVE, as well as initial results from our participation in the first Intensive Field Campaign of SAFARI 2000. We also describe SAVE's role in the Kalahari Transect Campaign (February/March 2000) in Zambia and Botswana.

  9. The ecology of Praomys (Mastomys) natalensis in southern Africa

    PubMed Central

    Isaäcson, Margaretha

    1975-01-01

    The only non-human host of Lassa virus so far identified is the multimammate mouse, Praomys (Mastomys) natalensis, but its precise role in the natural Lassa fever cycle remains to be determined. This species is also an important link in the plague cycle in southern Africa and is one of the commonest rodents of Africa. It is a prolific breeder and can be kept and bred easily in captivity. It is thus an excellent laboratory animal, although it needs to be handled with care because it is aggressive towards man and bites readily. The current status of knowledge of its taxonomy, ecology, distribution, and role as a disease vector is reviewed, but attention is drawn to the possibly disastrous consequences of attempting to eradicate a vector species before the natural cycle of the disease and the ecology of the vector are fully understood. ImagesFig. 2 PMID:1085218

  10. Transactional sex and HIV: understanding the gendered structural drivers of HIV in fishing communities in Southern Malawi

    PubMed Central

    MacPherson, Eleanor E; Sadalaki, John; Njoloma, Macdonald; Nyongopa, Victoria; Nkhwazi, Lawrence; Mwapasa, Victor; Lalloo, David G; Desmond, Nicola; Seeley, Janet; Theobald, Sally

    2012-01-01

    Background In Southern Malawi, the fishing industry is highly gendered, with men carrying out the fishing and women processing, drying and selling the fish. Research has shown that individuals living in fishing communities in low-income countries are particularly vulnerable to HIV infection. One of the key drivers of HIV in fishing communities is transactional sex. In the fishing industry this takes the form of “fish-for-sex” networks where female fish traders exchange sex with fishermen for access to or more favourable prices of fish. By controlling the means of production, the power dynamics in these exchanges favour men and can make it more difficult for women to negotiate safe sex. Methods Qualitative methods were used to collect data on gendered drivers of transactional sex in the fishing community and how different groups perceive HIV risk in these transactions. Observation, focus group discussions and semi-structured interviews were undertaken with members of the fishing communities, including men and women directly and indirectly involved in fishing. Results In fishing communities transactional sex was prevalent across a spectrum ranging from gift giving within relationships, to sex for fish exchanges, to sex worker encounters. Power differences between couples in transactional sexual encounters shape individual’s abilities to negotiate condom use (with women being at a particularly disadvantaged negotiating position). The context and motivations for transactional sex varied and was mediated by economic need and social position both of men and women. Female fish traders new to the industry and boat crew members who travelled for work and experienced difficult living conditions often engaged in transactional sex. Conclusions Transactional sex is common in Malawian fishing communities, with women particularly vulnerable in negotiations because of existing gendered power structures. Although knowledge and understanding of the HIV risk associated with

  11. Out-of-Pocket Expenditure on Chronic Non-Communicable Diseases in Sub-Saharan Africa: The Case of Rural Malawi

    PubMed Central

    Wang, Qun; Fu, Alex Z.; Brenner, Stephan; Kalmus, Olivier; Banda, Hastings Thomas; De Allegri, Manuela

    2015-01-01

    In Sub-Saharan Africa (SSA) the disease burden of chronic non-communicable diseases (CNCDs) is rising considerably. Given weaknesses in existing financial arrangements across SSA, expenditure on CNCDs is often borne directly by patients through out-of-pocket (OOP) payments. This study explored patterns and determinants of OOP expenditure on CNCDs in Malawi. We used data from the first round of a longitudinal household health survey conducted in 2012 on a sample of 1199 households in three rural districts in Malawi. We used a two-part model to analyze determinants of OOP expenditure on CNCDs. 475 respondents reported at least one CNCD. More than 60% of the 298 individuals who reported seeking care incurred OOP expenditure. The amount of OOP expenditure on CNCDs comprised 22% of their monthly per capita household expenditure. The poorer the household, the higher proportion of their monthly per capita household expenditure was spent on CNCDs. Higher severity of disease was significantly associated with an increased likelihood of incurring OOP expenditure. Use of formal care was negatively associated with the possibility of incurring OOP expenditure. The following factors were positively associated with the amount of OOP expenditure: being female, Alomwe and household head, longer duration of disease, CNCDs targeted through active screening programs, higher socio-economic status, household head being literate, using formal care, and fewer household members living with a CNCD within a household. Our study showed that, in spite of a context where care for CNCDs should in principle be available free of charge at point of use, OOP payments impose a considerable financial burden on rural households, especially among the poorest. This suggests the existence of important gaps in financial protection in the current coverage policy. PMID:25584960

  12. The Lithospheric Structure of Southern Africa from Magnetotelluric Sounding

    NASA Astrophysics Data System (ADS)

    Evans, R. L.; Jones, A. G.; Atekwana, E. A.

    2014-12-01

    Measurements of mantle electrical conductivity, made through the magnetotelluric method, offer considerable insight into the structure of cratonic lithosphere. A particularly expansive data set has been collected in Southern Africa, started through the Southern Africa Magnetotelluric Experiment (SAMTEX) experiment, now continuing north through Zambia as part of the Project for Rift Initiation Development and Evolution (PRIDE) experiment. The combined data set highlights large variability in lithospheric structure that broadly correlates with surface geology: cratonic lithosphere is generally thick and electrically resistive, while much thinner lithosphere is seen beneath mobile belts. In areas of relatively uniform resistivity structure, we have constructed resistivity-depth profiles and use new laboratory data to place constraints on the water content of lithospheric mantle. Uncertainty in our estimates arises from differences between different laboratory results, but our data are generally consistent with a slightly damp upper lithospheric mantle above a dry and strong cratonic root. Other areas show complexity of structure that is difficult to understand using current knowledge of conductivity -the Bushveld complex, where the mantle is highly conductive, is one such example. In southwestern Zambia, the lithosphere is seen to be very thin (around 50km) beneath mobile belt terrain, as was inferred nearly 40 years ago on the basis of high heatflow. The mantle is highly conductive, most likely due to a combination of elevated temperatures, water content and perhaps a trace amount of melting. This anomalous structure may be linked to the southwest propagation of the East African Rift system.

  13. Intracontinental deformation in southern Africa during the Late Cretaceous

    NASA Astrophysics Data System (ADS)

    Brown, Roderick; Summerfield, Michael; Gleadow, Andrew; Gallagher, Kerry; Carter, Andrew; Beucher, Romain; Wildman, Mark

    2014-12-01

    Intracontinental deformation accommodated along major lithospheric scale shear zone systems and within associated extensional basins has been well documented within West, Central and East Africa during the Late Cretaceous. The nature of this deformation has been established by studies of the tectonic architecture of sedimentary basins preserved in this part of Africa. In southern Africa, where the post break-up history has been dominated by major erosion, little evidence for post-break-up tectonics has been preserved in the onshore geology. Here we present the results of 38 new apatite fission track analyses from the Damara region of northern Namibia and integrate these new data with our previous results that were focused on specific regions or sections only to comprehensively document the thermo-tectonic history of this region since continental break-up in the Early Cretaceous. The apatite fission track ages range from 449 ± 20 Ma to 59 ± 3 Ma, with mean confined track lengths between 14.61 ± 0.1 μm (SD 0.95 μm) to 10.83 ± 0.33 μm (SD 2.84 μm). The youngest ages (c. 80-60 Ma) yield the longest mean track lengths, and combined with their spatial distribution, indicate major cooling during the latest Cretaceous. A simple numerical thermal model is used to demonstrate that this cooling is consistent with the combined effects of heating caused by magmatic underplating, related to the Paraná-Etendeka continental flood volcanism associated with rifting and the opening of the South Atlantic, and enhanced erosion caused by major reactivation of major lithospheric structures within southern Africa during a key period of plate kinematic change that occurred in the South Atlantic and SW Indian ocean basins between 87 and 56 Ma. This phase of intraplate tectonism in northern Namibia, focused in discrete structurally defined zones, is coeval with similar phases elsewhere in Africa and suggests some form of trans-continental linkage between these lithospheric zones.

  14. The Southern and Eastern Africa Consortium for Monitoring Educational Quality. Assessment GEMs No. 8

    ERIC Educational Resources Information Center

    Australian Council for Educational Research, 2015

    2015-01-01

    The Southern and Eastern Africa Consortium for Monitoring Educational Quality (SACMEQ) carries out large-scale cross-national research studies in member countries in the Southern and Eastern Africa region. It aims to assess the conditions of schooling and performance levels of learners and teachers in the areas of literacy and numeracy. SACMEQ has…

  15. New Technology Tools for Human Development? Towards Policy and Practice for Knowledge Societies in Southern Africa.

    ERIC Educational Resources Information Center

    Johnson, Phyllis

    2002-01-01

    Explores the interface of technology and education for human development in southern Africa. Uses the case of Mozambique to describe the challenges presented by the global marketplace and local policy. Outlines the vision of the New Partnership for Africa's Development Centre (SARDC) to reduce the digital divide for Africa. (CAJ)

  16. Distance Education in Southern Africa Conference, 1987. Papers 2: Issues in Education and Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Eighteen papers from the University of South Africa's Conference on Distance Education are presented on issues in education and distance education. They include: "Distance Education in Africa's Educational Development: The Case of Ghana" (Joe K. Ansere); "Distance Education: A Solution to the Economic Problems of Education in Southern Africa"…

  17. Atmospheric Transport and Photochemistry of Ozone Over Central Southern Africa During the Southern Africa Fire-Atmosphere Research Initiative

    NASA Technical Reports Server (NTRS)

    Tyson, P. D.; Garstang, M.; Thompson, A. M.; DAbreton, P.; Diab, R. D.; Browell, E. V.

    1997-01-01

    Vertically integrated back and forward trajectories for the 300-200, 700-500 and surface-800 hPa levels are calculated using Pretoria as point of origin for the Southern Africa Fire-Atmosphere Research Initiative (SAFARI) period September-October 1992. The transport fields are then combined to show both horizontal and vertical transport of air to and from Pretoria at the different levels. Air transport patterns in the vertical are linked to the occurrence of absolutely stable layers which are also evident in the 16 ozonesonde profiles recorded at Pretoria during SAFARI. The coherence of the stratification based on dynamical and ozone analysis permits the use of mean ozone profiles with air volume fluxes to interpret the ozone in terms of photochemistry and transport within stable layers. Extensive recirculation across the meridional plane at Pretoria implies that advection of ozone is slow and that photochemistry is responsible for the observed vertical structure over central southern Africa in September and October 1992. Requisite ozone formation rates are supported by model analysis of ozone and ozone precursors measured from SAFARI and Transport and Atmospheric Research Chemistry near the Equator-Atlantic aircraft.

  18. Overcoming constraints to the implementation of water demand management in southern Africa

    NASA Astrophysics Data System (ADS)

    Mwendera, E. J.; Hazelton, D.; Nkhuwa, D.; Robinson, P.; Tjijenda, K.; Chavula, G.

    This paper presents results of a study on water demand management status and overcoming constraints to implementation of water demand management in the southern African region, as part of Phase II of water demand management (WDM) programme implemented by the IUCN (The World Conservation Union). The study was conducted in Malawi, Namibia, South Africa, Swaziland, Zambia and Zimbabwe. The study methodology consisted of a survey of literature, and interviewing and communicating with stakeholders in order to learn from stakeholders on the critical constraints to WDM implementation and strategies to overcome them. The study has shown that, despite the potential savings that would accrue from implementation of WDM, the water sector across the southern African region continues to focus on water supply augmentation. There are inadequate financial and human resources for rehabilitation, operation and maintenance of water conveyance systems resulting in system leaks, which contribute to high levels of unaccounted-for water, a situation that masks the potential benefits of WDM. In most countries, the water sector operates on ad-hoc sub-sector water user objectives, which provided guidelines only for development and management purposes. Most of the institutional frameworks have remained diffuse, resulting into poor performance in the sector, and into crisis management in the water resources development. Though the WDM policy in most countries is already accessible through guidelines for catchment management institutions and water supply institutions; there is a lack of broad commitment to implementing them. In other countries the instruments are relatively new and have not been applied widely. Similarly, the effectiveness of instruments has not been well evaluated in most countries. In countries where policy is weak there is often a lack of clarity as to who is responsible for WDM implementation, and even less clarity on who is responsible for facilitating and monitoring

  19. Terrestrial heat flow in east and southern Africa

    NASA Astrophysics Data System (ADS)

    Nyblade, Andrew A.; Pollack, Henry N.; Jones, D. L.; Podmore, Francis; Mushayandebvu, Martin

    1990-10-01

    We report 26 new heat flow and 13 radiogenic heat production measurements from Zimbabwe, Zambia and Tanzania, together with details and some revisions of 18 previous heat flow measurements by other investigators from Kenya and Tanzania. These measurements come from Archean cratons, Proterozoic mobile belts, and Mesozoic and Cenozoic rifts. Heat flow data from eight new sites in the Archean Zimbabwe Craton are consistent with previous measurements in the Archean Kaapvaal-Zimbabwe Craton and Limpopo Belt (Kalahari Craton) and do not change the mean heat flow of 47±2 mW m-2 (standard error of the mean) in the Kalahari Craton based on 53 previous measurements. Eight new sites in the Archean Tanzania Craton give a mean heat flow of 34±4 mW m-2. The mean heat flow from nine sites in the Proterozoic Mozambique Belt to the east of the Tanzania Craton in Kenya and Tanzania is 47±4 mW m-2. Twelve measurements in the Mesozoic rifted continental margin in east Africa give a mean heat flow of 68±4 mW m-2; four measurements in the Mesozoic Luangwa and Zambezi Rifts range from 44 to 110 mW m-2 with a mean of 76±14 mW m-2. In comparing heat flow in east and southern Africa, we observe a common heat flow pattern of increasing heat flow away from the centers of the Archean cratons. This pattern suggests a fundamental difference in lithospheric thermal structure between the Archean cratons and the Proterozoic and early Paleozoic mobile belts which surround them. Superimposed on this common pattern are two regional variations in heat flow. Heat flow in the Tanzania Craton is lower by about 13 mW m-2 than in the Kalahari Craton, and in the Mozambique Belt in east Africa heat flow is somewhat lower than in the southern African mobile belts at similar distances from the Archean cratonic margin. The two regional variations can be explained in several ways, none of which can as yet be elevated to a preferred status: (1) by variations in crustal heat production, (2) by thin

  20. New Seismic Images of Crustal Structure Beneath Southern Africa

    NASA Astrophysics Data System (ADS)

    Delph, J. R.; Fouch, M. J.

    2012-12-01

    The deep and complex history of southern Africa makes it a geological nexus for understanding how crust forms, evolves, and survives plate tectonic processes over billions of years. The goal of this study is to provide new constraints on crustal thickness and composition across the Kaapvaal and Zimbabwe Cratons and surrounding mobile belts across a range of geologic terranes ranging in age from the Archean to the Paleozoic. We use data gathered from the 1997-1999 Southern Africa Seismic Experiment (SASE), a broadband seismometer deployment with ~75 km station spacing. We generated P-wave receiver functions for 79 stations using the iterative deconvolution method of Ligorria and Ammon (1999) with a Gaussian pulse width of 2.5, which corresponds to a dominant period of ~2 sec in the receiver functions. We utilized the Funclab receiver function analysis software of Eagar and Fouch (2012) to trace edit receiver functions, and subsequently perform H-κ stacking and Common Conversion Point (CCP) imaging. The use of CCP stacking differentiates our study from previous studies using these data (e.g. Nguuri et al., 2001, Nair et al., 2006), as it provides us with a continuous three-dimensional image of crustal variations throughout southern Africa. We find that crustal thickness in mobile belt regions is thick compared to the cratons, with the exception of the area affected by the Bushveld Complex. The Kaapvaal and eastern Zimbabwe Cratons have a well-defined average Moho depth of ~34 km and Vp/Vs of ~1.73, indicative of intermediate average crustal composition. These results are consistent with a relatively unmodified continental crust due to limited deformation history of these regions since formation. Conversely, the Archean Okwa-Magondi belt, western Zimbabwe Craton, Proterozoic Kheiss thrust belt and Namaqua-Natal, and Paleozoic Cape-Fold belts have Moho depths with a wide range of values from ~36 km to ~47 km, and Vp/Vs values ranging from 1.74 to 1.85 which seem to

  1. Assessing and Responding to Palliative Care Needs in Rural Sub-Saharan Africa: Results from a Model Intervention and Situation Analysis in Malawi

    PubMed Central

    Kalanga, Noel; Keck, James W.; Wroe, Emily B.; Phiri, Atupere; Mayfield, Alishya; Chingoli, Felix; Beste, Jason A.; Tengatenga, Listern; Bazile, Junior

    2014-01-01

    Introduction Palliative care is rarely accessible in rural sub-Saharan Africa. Partners In Health and the Malawi government established the Neno Palliative Care Program (NPCP) to provide palliative care in rural Neno district. We conducted a situation analysis to evaluate early NPCP outcomes and better understand palliative care needs, knowledge, and preferences. Methods Employing rapid evaluation methodology, we collected data from 3 sources: 1) chart review of all adult patients from the NPCP’s first 9 months; 2) structured interviews with patients and caregivers; 3) semi-structured interviews with key stakeholders. Results The NPCP enrolled 63 patients in its first 9 months. Frequent diagnoses were cancer (n = 50, 79%) and HIV/AIDS (n = 37 of 61, 61%). Nearly all (n = 31, 84%) patients with HIV/AIDS were on antiretroviral therapy. Providers registered 112 patient encounters, including 22 (20%) home visits. Most (n = 43, 68%) patients had documented pain at baseline, of whom 23 (53%) were treated with morphine. A majority (n = 35, 56%) had ≥1 follow-up encounter. Mean African Palliative Outcome Scale pain score decreased non-significantly between baseline and follow-up (3.0 vs. 2.7, p = 0.5) for patients with baseline pain and complete pain assessment documentation. Providers referred 48 (76%) patients for psychosocial services, including community health worker support, socioeconomic assistance, or both. We interviewed 36 patients referred to the NPCP after the chart review period. Most had cancer (n = 19, 53%) or HIV/AIDS (n = 10, 28%). Patients frequently reported needing income (n = 24, 67%) or food (n = 22, 61%). Stakeholders cited a need to make integrated palliative care widely available. Conclusions We identified a high prevalence of pain and psychosocial needs among patients with serious chronic illnesses in rural Malawi. Early NPCP results suggest that comprehensive palliative care can be provided in rural

  2. El Niño Southern Oscillation (ENSO) and annual malaria incidence in Southern Africa.

    PubMed

    Mabaso, Musawenkosi L H; Kleinschmidt, Immo; Sharp, Brian; Smith, Thomas

    2007-04-01

    We evaluated the association between annual malaria incidence and El Niño Southern Oscillation (ENSO) as measured by the Southern Oscillation Index (SOI) in five countries in Southern Africa from 1988 to 1999. Below normal incidence of malaria synchronised with a negative SOI (El Niño) and above normal incidence with a positive SOI (La Niña), which lead to dry and wet weather conditions, respectively. In most countries there was a positive relationship between SOI and annual malaria incidence, especially where Anopheles arabiensis is a major vector. This mosquito breeds in temporary rain pools and is highly sensitive to fluctuations in weather conditions. South Africa and Swaziland have the most reliable data and showed the strongest associations, but the picture there may also be compounded by the moderating effect of other oscillatory systems in the Indian Ocean. The impact of ENSO also varies over time within countries, depending on existing malaria control efforts and response capacity. There remains a need for quantitative studies that at the same time consider both ENSO-driven climate anomalies and non-ENSO factors influencing epidemic risk potential to assess their relative importance in order to provide an empirical basis for malaria epidemic forecasting models. PMID:17064744

  3. Upper Permian fluviolacustrine deposits of southern Africa and the late Permian climate southern Gondwana

    SciTech Connect

    Yemane, K. . Dept. of Geology Bryn Mawr Coll., PA . Dept. of Geology)

    1993-03-01

    Upper Permian-age fluviolacustrine deposits are widespread throughout southern Africa. In the southern part of the subcontinent, where deposition took place in foreland basin settings, the sequences are thicker and fluvial-dominated whereas, lacustrine-dominated deposits accumulated in settings of low relief, broad warping and mild faulting at the northern end. The geographic extent and lateral correlatability of these deposits suggest the existence of concurrent, perhaps interconnected, giant lakes within major fluvial frameworks throughout the subcontinent, thousands of miles inland from the sea. This period of major lake development within fluvial depositional settings suggests climatic conditions that sustained a uniquely wet continental environment, deep in the heart of the Gondwanan supercontinent. Simulations based on various general circulation and energy balance climate models predict extreme seasonal temperatures and aridity for Gondwana at the palaeolatitudes of southern Africa during the Late Permian. On the other hand, distribution of climate-sensitive rocks, palynologic and palaeobotanic data and vertebrate fossils, coroborate the temperature climate documented by sedimentologic studies. The erroneous modeling results may have arisen from the fact that the models do not employ palaeogeographies that accommodate the existence of the vast lakes and rivers of Gondwana. The Late Permian palaeogeography of series of giant lakes within major fluvial frameworks would have had considerable influences on the regional climate. This suggests that it is imperative that numerical modeling studies incorporate accurate palaeogeographies, constructed based on available geological data, in order to recreate past climates with acceptable degree of accuracy.

  4. Uranium isotopes in surface waters from southern Africa

    NASA Astrophysics Data System (ADS)

    Kronfeld, J.; Vogel, J. C.

    1991-07-01

    The 234U/ 238U activity ratio in river water in southern Africa is generally higher than that reported for rivers in other regions of the world. This is interpreted as due to the prevailing environmental conditions: in this warm dry region mechanical weathering predominates over chemical weathering, causing the isotope activity ratio of leached uranium to be, on average, 2.03 ± 0.42 as compared to a ratio of 1.20 for river water in the more humid tropical and temperate regions. The isotopic composition of leachable uranium from river sediment is similar to that in the water. Rivers draining the Witwatersrand gold and uranium mining area clearly show pollution inputs characterised by high uranium content and low activity ratios.

  5. Women's stories of abortion in southern Gabon, Africa.

    PubMed

    Hess, Rosanna F

    2007-01-01

    The purpose of this study was to explore the reasons women in rural, southern Gabon, Africa, chose to terminate their pregnancies, the methods used to induce abortions, and postabortion effects experienced by these women. Abortion is illegal in this country. A descriptive qualitative design guided the methodology for this study. Five women with a history of induced abortion were interviewed in-depth for their abortion story. Reasons cited for an abortion included lack of financial and partner support. Abortion methods included oral, rectal, and vaginal concoctions of leaves, bark, and water and over-the-counter medications, including misoprostol. Affects were physical, spiritual, and relational. Health care professionals need to provide women with guidance for appropriate contraceptive usage. Abortion after-care of women with physical and spiritual needs is important. Future research is suggested on the use of misoprostol in Gabon to understand its affects on women's reproductive health. PMID:17202528

  6. How community trust was gained by an NGO in Malawi, Central Africa, to mitigate the impact of HIV/AIDS.

    PubMed

    MacIntyre, Linda M; Waters, Catherine M; Rankin, Sally H; Schell, Ellen; Laviwa, Jones; Luhanga, Melton Richard

    2013-07-01

    Trust is valuable social capital that is essential for effective partnerships to improve a community's health. Yet, how to establish trust in culturally diverse communities is elusive for many researchers, practitioners, and agencies. The purpose of this qualitative study was to obtain perspectives of individuals working for a nongovernmental organization (NGO) about gaining community trust in Malawi in order to mitigate the impact of HIV/AIDS. Twenty-six interviews were conducted over 12 months. Content analysis revealed the relationship between NGO staff and the community is crucial to gaining community trust. Gender, social context, and religious factors influence the establishment of trust within the relationship, but NGO assumptions about the community can erode community trust. Nurses and other health professionals working with the NGOs can help create conditions to build trust in an ethically and culturally sensitive manner whereby communities can develop processes to address their own health concerns. PMID:23610161

  7. The current status of neurocysticercosis in Eastern and Southern Africa.

    PubMed

    Mafojane, N A; Appleton, C C; Krecek, R C; Michael, L M; Willingham, A L

    2003-06-01

    Some information has been documented on the epidemiology of neurocysticercosis in Eastern and Southern Africa through the monitoring of hospital-based patients with neurocysticercosis, community-based serological surveys of particular socio-economic groups of people and surveys of porcine cysticercosis. Studies have revealed that non-pork eaters have as great a chance of infection as a pork eater, the Xhosa-speaking people of the Eastern Cape Province have the highest prevalence of cysticercosis/taeniosis in South Africa probably due to the common practice of free-range pig farming and the lack of sanitation in these areas. Several studies have revealed high prevalence rates in children and interestingly, patients with active cysts suffering from epilepsy. A startling mode of transmission is where self-trained healers use Taenia segments either for benevolent (e.g. in the treatment of severe intestinal tapeworm infections) or malevolent (evil) purposes (e.g. women "poisoning" an unfaithful husband or lover by adding the contents of Taenia solium segments to beer). PMID:12781375

  8. Multi-scale investigation of shrub encroachment in southern Africa

    NASA Astrophysics Data System (ADS)

    Aplin, Paul; Marston, Christopher; Wilkinson, David; Field, Richard; O'Regan, Hannah

    2016-04-01

    There is growing speculation that savannah environments throughout Africa have been subject to shrub encroachment in recent years, whereby grassland is lost to woody vegetation cover. Changes in the relative proportions of grassland and woodland are important in the context of conservation of savannah systems, with implications for faunal distributions, environmental management and tourism. Here, we focus on southern Kruger National Park, South Africa, and investigate whether or not shrub encroachment has occurred over the last decade and a half. We use a multi-scale approach, examining the complementarity of medium (e.g. Landsat TM and OLI) and fine (e.g. QuickBird and WorldView-2) spatial resolution satellite sensor imagery, supported by intensive field survey in 2002 and 2014. We employ semi-automated land cover classification, involving a hybrid unsupervised clustering approach with manual class grouping and checking, followed by change detection post-classification comparison analysis. The results show that shrub encroachment is indeed occurring, a finding evidenced through three fine resolution replicate images plus medium resolution imagery. The results also demonstrate the complementarity of medium and fine resolution imagery, though some thematic information must be sacrificed to maintain high medium resolution classification accuracy. Finally, the findings have broader implications for issues such as vegetation seasonality, spatial transferability and management practices.

  9. Gender, ageing & carework in East and Southern Africa: A review

    PubMed Central

    Seeley, Janet

    2016-01-01

    An estimated 58 million persons aged 60-plus live in sub-Saharan Africa; by 2050 that number will rise sharply to 215 million. Older Africans traditionally get care in their old age from the middle generation. But in East and Southern Africa, HIV has hollowed out that generation, leaving many older persons to provide care for their children’s children without someone to care for him or herself in old age. Simultaneously, the burden of disease among older persons is changing in this region. The result is a growing care deficit. This article examines the existing literature on care for and by older persons in this region, highlighting understudied aspects of older persons’ experiences of ageing and care – including the positive impacts of carework, variation in the region, and the role of resilience and pensions. We advance a conceptual framework of gendered identities – for both men and women – and intergenerational social exchange to help focus and understand the complex interdependent relationships around carework, which are paramount in addressing the needs of older persons in the current care deficit in this region, and the Global South more generally. PMID:25947225

  10. Semivolatile Particulate Organic Material Southern Africa during SAFARI 2000

    NASA Technical Reports Server (NTRS)

    Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.

    2005-01-01

    During August and September 2000, the University of Washington's Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the h e troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna frre emissions averaged 130 micrograms per cubic meter. This aerosol was 85% carbonaceous mated.

  11. Semivolatile particulate organic material in southern Africa during SAFARI 2000

    NASA Astrophysics Data System (ADS)

    Eatough, D. J.; Eatough, N. L.; Pang, Y.; Sizemore, S.; Kirchstetter, T. W.; Novakov, T.; Hobbs, P. V.

    2003-07-01

    During August and September 2000, the University of Washington's (UW) Cloud and Aerosol Research Group (CARG) with its Convair-580 research aircraft participated in the Southern African Fire-Atmosphere Research Initiative (SAFARI) 2000 field study in southern Africa. Aboard this aircraft was a Particle Concentrator-Brigham Young University Organic Sampling System (PC-BOSS), which was used to determine semivolatile particulate material with a diffusion denuder sampler. Denuded quartz filters and sorbent beds in series were used to measure nonvolatile and semivolatile materials, respectively. Results obtained with the PC-BOSS are compared to those obtained with conventional quartz-quartz and Teflon-quartz filter pack samplers. Various 10-120 min integrated samples were collected during flights through the free troposphere, in the atmospheric boundary layer, and in plumes from savanna fires. Significant fine particulate semivolatile organic compounds (SVOC) were found in all samples. The SVOC was not collected by conventional filter pack samplers and therefore would not have been determined in previous studies that used only filter pack samplers. The SVOC averaged 24% of the fine particulate mass in emissions from the fires and 36% of the fine particulate mass in boundary layer samples heavily impacted by aged emissions from savanna fires. Concentrations of fine particulate material in the atmospheric mixed layer heavily impacted by aged savanna fire emissions averaged 130 μg m-3. This aerosol was 85% carbonaceous material.

  12. The Colposcopic Atlas of Schistosomiasis in the Lower Female Genital Tract Based on Studies in Malawi, Zimbabwe, Madagascar and South Africa

    PubMed Central

    Norseth, Hanne M.; Ndhlovu, Patricia D.; Kleppa, Elisabeth; Randrianasolo, Bodo S.; Jourdan, Peter M.; Roald, Borghild; Holmen, Sigve D.; Gundersen, Svein G.; Bagratee, Jayanthilall; Onsrud, Mathias; Kjetland, Eyrun F.

    2014-01-01

    Background Schistosoma (S.) haematobium is a neglected tropical disease which may affect any part of the genital tract in women. Female genital schistosomiasis (FGS) may cause abnormal vaginal discharge, contact bleeding, genital tumours, ectopic pregnancies and increased susceptibility to HIV. Symptoms may mimic those typical of sexually transmitted infections (STIs) and women with genital schistosomiasis may be incorrectly diagnosed. An expert consensus meeting suggested that the following findings by visual inspection should serve as proxy indicators for the diagnosis of schistosomiasis of the lower genital tract in women from S. haematobium endemic areas: sandy patches appearing as (1) single or clustered grains or (2) sandy patches appearing as homogenous, yellow areas, or (3) rubbery papules. In this atlas we aim to provide an overview of the genital mucosal manifestations of schistosomiasis in women. Methodology/Principal findings Photocolposcopic images were captured from women, between 1994 and 2012 in four different study sites endemic for S. haematobium in Malawi, Zimbabwe, South Africa and Madagascar. Images and specimens were sampled from sexually active women between 15 and 49 years of age. Colposcopic images of other diseases are included for differential diagnostic purposes. Significance This is the first atlas to present the clinical manifestations of schistosomiasis in the lower female genital tract. It will be freely available for online use, downloadable as a presentation and for print. It could be used for training purposes, further research, and in clinical practice. PMID:25412334

  13. Upper mantle shear and compressional velocity structures beneath southern Africa

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Wen, L.; Weidner, D.

    2005-12-01

    The velocity structures in the upper mantle play an important role in understanding mantle composition and temperature. In this study, we constrain the fine seismic shear and compressional velocity structures in the upper mantle beneath southern Africa by waveform modeling the seismic data recorded in the Kaapvaal array at the distance range of 9°-28° for an event occurring near Lake Tanganyika in east Africa. We then explore mineralogical models that would explain the inferred seismic structures. The seismic data recorded at this distance range provide excellent sampling of both the SH and P velocity structures in the top 800 km of the mantle. The first direct arrivals in both the P and SH data become weak at an epicentral distance of about 20°, indicating presence of a low velocity zone beneath southern Africa at a depth of about 150 km. In the SH data, the observed travel times of the reflected and triplicated phases off the 410-km discontinuity require a large shear velocity reduction in the low velocity zone and a small shear velocity jump across the 410-km discontinuity; the observed triplications at the 660-km discontinuity require a large shear velocity jump across the 660-km discontinuity. In the P wave data, the observed travel times of the triplication at the 410-km discontinuity suggest a small P wave velocity reduction in the low velocity zone, a large velocity jump across the 410-km discontinuity and a high Vp/Vs ratio in the transition zone; the triplication at the 660-km discontinuity is indiscernible, suggesting a small P wave velocity jump across the 660-km discontinuity. Overall, the seismic data can be explained by a 150-km thick high-velocity lid overlying a low velocity zone between 150 km and 405 km depths with a P wave velocity reduction of -1.5% and an SH wave velocity reduction of -9%, followed by a small shear velocity jump of 3% and a large P velocity jump of 10% across the 410-km discontinuity, a transition zone with a high Vp

  14. Circulation patterns associated with droughts over southern Africa

    NASA Astrophysics Data System (ADS)

    Garanganga, B.

    2002-12-01

    The paper highlights the circulation patterns associated with droughts that have demonstrated the vulnerability of the socioeconomic development of around 200 million people from 14 the Southern African Development Community (SADC) countries to the vagaries of the climate system. The recent, apparently perennial droughts juxtaposed with floods across southern Africa have to be seen against the background of advances made by the scientific community in the understanding of the global ocean-atmosphere system. The paper seeks to contribute to such advances science is making in order to make humankind benefit from the knowledge science has provided. The data used in the analyses include actual rainfall from the SADC countries and those from the United States NOAA (NCEP/NCAR Reanalysis) data banks. The paper briefly looks at the regional climatology of the SADC countries, which shows that rains fall within the period October during one year to March of the following year. Most of the damaging droughts have tended to occur during January to March. Thus, the more detailed analysis of the circulation characteristics has a focus of composite of these months. A few recent drought years are selected for analyzing of the dynamical structures of the regional circulation patterns and the tropical ocean and global atmosphere. These tended to coincide with El Ninos. However, the selected years include the recent drought during the 2001/2002 rainfall season, which occurred in a neutral El Nino-Southern Oscillation (ENSO) phase. There emerged significant similarity between rainfall anomaly variability and the ENSO signals. The many parameters of the atmosphere showed consistent characteristics in different drought years. The regional circulation patterns associated with droughts show similarities in both active and neutral ENSO years. The study also shows how possible generators of the climate anomalies can be grouped together. Thus the diagnosis of the various fields contributes to

  15. An assessment of the utility of optically-stimulated luminescence to date sediments from Lakes Malawi, Bosumtwi, and Tanganyika, Africa

    NASA Astrophysics Data System (ADS)

    Gomez, J.; Forman, S. L.; Pierson, J.; Scholz, C.; Peck, J.; Heil, C.; King, J.; Shanahan, T.; Overpeck, J.; Koeberl, C.; Milkereit, B.

    2005-12-01

    An exciting recent development in geochronology is the advent of optically-stimulated luminescence (OSL) for dating late Quaternary sediments. OSL signal of mineral grains is reset by exposure to sunlight prior to deposition and a time-sensitive charge is acquired from exposure to ionizing radiation post burial. The OSL signal is highly sensitive to solar resetting, with background counts rendered after few minutes of sunlight exposure. OSL geochronology can yield decadal resolution in the past 1000 years, a period of limited precision for radiocarbon dating and potentially date sediment spanning the past 200 to 400 ka. Nearly continuous sedimentary records from African lakes provide unparalleled opportunities to develop new OSL dating approaches to constrain hydro-climatic events in the tropics. A variety of OSL geochronologic approaches are attempted for sediments from Lakes Malawi, Bosumtwi and Tanganyika providing an internal test of reproducibility. Accuracy is assessed by OSL dating levels with radiocarbon ages and with correlated chronologic control e.g. from the sediment magnetic signature or sediment carbon to atmosphere methane relations. The fine-grained (3-11 micron) polymineral and quartz fractions and for coarser levels the quartz fine sand is extracted for dating. Additive and regenerative dose procedures using multiple and single aliquots under blue, green and infrared light exposure are used to estimate the post-burial paleodose. A regenerative procedure with dose normalization and stepped preheating (140-180° C) provides a particularly robust approach for dating sediments greater than 75 ka. OSL emissions for sediment from Lake Malawi for the past ca. 100 ka are not at saturated dose and are amenable for dating by a variety of methods. In contrast sediments from Lake Bosumtwi, with a probable Sahel dust source, exhibit saturation in OSL signal for sediments ca. 100 ka old, necessitating the using of regenerative approaches. The concordance

  16. Carbon isotope ratios and impurities in diamonds from Southern Africa

    NASA Astrophysics Data System (ADS)

    Kidane, Abiel; Koch-Müller, Monika; Morales, Luiz; Wiedenbeck, Michael; De Wit, Maarten

    2015-04-01

    We are investigating the sources of diamonds from southern Africa by studying both their carbon isotopic composition and chemical impurities. Our samples include macro-sized diamonds from River Ranch kimberlite in Zimbabwe and the Helam and Klipspringer kimberlitic deposits from South Africa, as well as micro-sized diamonds from Klipspringer and Premier kimberlites in South Africa. We have characterized the samples for their structurally bounded nitrogen, hydrogen and platelets defect using a Fourier Transmission Infrared Spectroscopy (FTIR). Using the DiaMap routine, open source software (Howell et al., 2012), IR spectra were deconvulated and quantified for their nitrogen (A, B and D components) and hydrogen contents. High to moderate nitrogen concentrations (1810 to 400 µg/g; 400 to 50 µg/g respectively) were found in diamonds from Klipspringer and Helam. Moderate to low (<50 µg/g) nitrogen concentrations were observed in diamonds from Premier and River Ranch. Type II diamonds, i.e. diamonds with no N impurities, which are presumed to have been derived from ultramafic sources, are found in the River Ranch deposit. The macro- and micro-size diamonds from the Klipspringer deposit display similar nitrogen defects, with higher nitrogen concentration and more frequent D components found in the macro-size diamonds. One of the first steps towards reliable carbon isotope studies is the development of calibration materials for SIMS carbon isotopic analyses. We have investigated candidate materials both from a polycrystalline synthetic diamond sheet and two natural gem quality diamonds from Juina (Brazil). Electron-based images of the synthetic diamond sheet, obtained using GFZ Potsdam's dual beam FIB instrument, show many diamond grains with diameters greater than 35 µm. SIMS testing of the isotopic homogeneity of the back and front sides of the synthetic sheets reveal similar 13C/12C ratio within a RSD of <1 ‰ . SIMS isotopic analyses of the two natural diamond RMs

  17. How are health professionals earning their living in Malawi?

    PubMed Central

    Muula, Adamson S; Maseko, Fresier C

    2006-01-01

    Background The migration of health professionals from southern Africa to developed nations is negatively affecting the delivery of health care services in the source countries. Oftentimes however, it is the reasons for the out-migration that have been described in the literature. The work and domestic situations of those health professionals continuing to serve in their posts have not been adequately studied. Methods The present study utilized a qualitative data collection and analysis method. This was achieved through focus group discussions and in-depth interviews with health professionals and administrators to determine the challenges they face and the coping systems they resort to and the perceptions towards those coping methods. Results Health professionals identified the following as some of the challenges there faced: inequitable and poor remuneration, overwhelming responsibilities with limited resources, lack of a stimulating work environment, inadequate supervision, poor access to continued professionals training, limited career progression, lack of transparent recruitment and discriminatory remuneration. When asked what kept them still working in Malawi when the pressures to emigrate were there, the following were some of the ways the health professionals mentioned as useful for earning extra income to support their families: working in rural areas where life was perceived to be cheaper, working closer to home village so as to run farms, stealing drugs from health facilities, having more than one job, running small to medium scale businesses. Health professionals would also minimize expenditure by missing meals and walking to work. Conclusion Many health professionals in Malawi experience overly challenging environments. In order to survive some are involved in ethically and legally questionable activities such as receiving "gifts" from patients and pilfering drugs. The efforts by the Malawi government and the international community to retain health

  18. Next Year Will Be a Good Year--Southern Africa's Dreadful Dryland Farming Disaster.

    ERIC Educational Resources Information Center

    Johns, Maria

    1992-01-01

    Discusses how agricultural productivity in drought stricken southern Africa is diminished by economically and ecologically unsustainable agricultural practices. A vignette provides alternative farming techniques appropriate for dry regions with an emphasis on respect for the land. (MCO)

  19. Language Policy and Practice in the Multilingual Southern African Development Community

    ERIC Educational Resources Information Center

    Mooko, Theophilus

    2009-01-01

    This study explores the language policy and practice of the Southern African Development Community (SADC), an African regional economic organisation made up of 14 member states (Angola, Botswana, Democratic Republic of Congo, Lesotho, Madagascar, Malawi, Mauritius, Mozambique, Namibia, South Africa, Swaziland, United Republic of Tanzania, Zambia…

  20. Variations in Reading Achievement across 14 Southern African School Systems: Which Factors Matter?

    ERIC Educational Resources Information Center

    Hungi, Njora; Thuku, Florence W.

    2010-01-01

    In this study the authors employed a multilevel analysis procedure in order to examine the pupil and school levels factors that contributed to variation in reading achievement among Grade 6 primary school pupils in 14 southern African school systems (Botswana, Kenya, Lesotho, Malawi, Mauritius, Mozambique, Namibia, Seychelles, South Africa,…

  1. "That Indefinable Something Besides": Southern Africa, British Identity, and the Authorial Informant, 1883-1924

    ERIC Educational Resources Information Center

    Free, Melissa

    2009-01-01

    This project examines the role of southern Africa (from the Cape to the Zambezi) in the constitution of British identity from the rise of the systematic exploitation of the region's mineral deposits through the close of World War One. Reading a wide variety of print culture produced by South Africa's "authorial informants"--British authors who…

  2. Africana Acquisitions; Report of a Publication Survey Trip to Nigeria, Southern Africa, and Europe, 1972.

    ERIC Educational Resources Information Center

    Witherell, Julian W.

    A publication survey trip to Nigeria, Southern Africa, and Europe was taken by Julian W. Witherell of the African Section of the Library of Congress in 1972. The purpose of the trip was to improve the flow of publications about Africa to the Library of Congress. The trip was successful in that personal contacts helpful in obtaining local materials…

  3. Potential plant poisonings in dogs and cats in southern Africa.

    PubMed

    Botha, C J; Penrith, M L

    2009-06-01

    Plant poisoning occurs less commonly in dogs and cats than in herbivorous livestock, but numerous cases have been documented worldwide, most of them caused by common and internationally widely cultivated ornamental garden and house plants. Few cases of poisoning of cats and dogs have been reported in southern Africa, but many of the plants that have caused poisoning in these species elsewhere are widely available in the subregion and are briefly reviewed in terms of toxic principles, toxicity, species affected, clinical signs, and prognosis. The list includes Melia azedarach (syringa), Brunfelsia spp. (yesterday, today and tomorrow), Datura stramonium (jimsonweed, stinkblaar), a wide variety of lilies and lily-like plants, cycads, plants that contain soluble oxalates, plants containing cardiac glycosides and other cardiotoxins and euphorbias (Euphorbia pulcherrima, E. tirucalli). Poisoning by plant products such as macadamia nuts, onions and garlic, grapes and raisins, cannabis (marijuana, dagga) or hashish and castor oil seed or seedcake is also discussed. Many of the poisonings are not usually fatal, but others frequently result in death unless rapid action is taken by the owner and the veterinarian, underlining the importance of awareness of the poisonous potential of a number of familiar plants. PMID:19831265

  4. Globalization and occupational health: a perspective from southern Africa.

    PubMed Central

    Loewenson, R.

    2001-01-01

    Increased world trade has generally benefited industrialized or strong economies and marginalized those that are weak. This paper examines the impact of globalization on employment trends and occupational health, drawing on examples from southern Africa. While the share of world trade to the world's poorest countries has decreased, workers in these countries increasingly find themselves in insecure, poor-quality jobs, sometimes involving technologies which are obsolete or banned in industrialized countries. The occupational illness which results is generally less visible and not adequately recognized as a problem in low-income countries. Those outside the workplace can also be affected through, for example, work-related environmental pollution and poor living conditions. In order to reduce the adverse effects of global trade reforms on occupational health, stronger social protection measures must be built into production and trade activities, including improved recognition, prevention, and management of work-related ill-health. Furthermore, the success of production and trade systems should be judged on how well they satisfy both economic growth and population health. PMID:11584735

  5. Petroleum developments in central and southern Africa in 1979

    SciTech Connect

    Rachwal, C.A.; Destefano, E.R.

    1980-11-01

    This review presents developments in petroleum exploration and production during 1979 in 44 countries of central and southern Africa. Petroleum production from 7 countries increased 16.6% to a new record 1,006,846,691 bbl (2.758 million b/d). Nigeria increased production 21% to 845 million, Congo 11.5% to 19 million, and Cameroon 17.6% to 12.5 million bbl. Gabon continued to show a decline in production, off 7.6% at 70.5 million bbl. Surface exploration work decreased 17.5% to 174.9 party-months, though figures on Nigeria are incomplete. Exploration drilling yielded 43 oil and 10 gas wells out of 111 drilled, a 47.7% success rate. Cameroon had 21 and Congo 8 new-field discovery and appraisal wells, up from 11 and 1 respectively in 1978. Development wells numbered 137 of which 86% were successful completions; 45 rigs were operating at year end.

  6. Understanding Models of Palliative Care Delivery in Sub-Saharan Africa: Learning From Programs in Kenya and Malawi.

    PubMed

    Downing, Julia; Grant, Liz; Leng, Mhoira; Namukwaya, Elizabeth

    2015-09-01

    The need for palliative care has never been greater. From being significantly present in only five African countries in 2004, palliative care is now delivered in nearly 50% of African countries; however, less than 5% of people in need receive it. To scale-up palliative care, we need greater knowledge about how different models of palliative care work within different health systems. A case study evaluation was undertaken in Kenya and Malawi to define the models used, contextualize them, and identify challenges, best practices, and transferable lessons for scale-up. Visits were made to seven sites and, using an audit tool, data were collected from program staff, hospital staff, and local stakeholders, and care observed as appropriate. Three models of palliative care service delivery were identified, which supports the existing literature, that is, specialist, district hospital level, and community level. However, in looking further, findings show that the major determinants for each model were a set of philosophical questions and assumptions underpinning each and influencing staff and patient decision-making, planning, and allocation of resources. The health system structure and the beliefs about palliative care determined, and were determined most by, referrals, the patient journey, the centeredness of the model, and role definition and training. The models are also closely associated with the physical setting of services. Understanding how the services have developed because of, and indeed despite the geographical setting and the system level, provides us with a different set of indicators of program structure incorporated into the three models. The analysis of models provides pointers to future planning for palliative care. PMID:25936938

  7. Persistent C3 vegetation accompanied Plio-Pleistocene hominin evolution in the Malawi Rift (Chiwondo Beds, Malawi).

    PubMed

    Lüdecke, Tina; Schrenk, Friedemann; Thiemeyer, Heinrich; Kullmer, Ottmar; Bromage, Timothy G; Sandrock, Oliver; Fiebig, Jens; Mulch, Andreas

    2016-01-01

    The development of East African savannas is crucial for the origin and evolution of early hominins. These ecosystems, however, vary widely in their fraction of woody cover and today range from closed woodland to open grassland savanna. Here, we present the first Plio-Pleistocene long-term carbon isotope (δ(13)C) record from pedogenic carbonate and Suidae teeth in the southern East African Rift (EAR). These δ(13)C data from the Chiwondo and Chitimwe Beds (Karonga Basin, Northern Malawi) represent a southern hemisphere record in the EAR, a key region for reconstructing vegetation patterns in today's Zambezian Savanna, and permit correlation with data on the evolution and migration of early hominins in today's Somali-Masai Endemic Zone. The sediments along the northwestern shore of Lake Malawi contain fossils attributed to Homo rudolfensis and Paranthropus boisei. The associated hominin localities (Uraha, Malema) are situated between the well-known hominin bearing sites of the Somali-Masai Endemic Zone in the Eastern Rift and the Highveld Grassland in southern Africa, and fill an important geographical gap for hominin research. Persistent δ(13)C values around -9‰ from pedogenic carbonate and suid enamel covering the last ∼4.3 Ma indicate a C3-dominated closed environment with regional patches of C4-grasslands in the Karonga Basin. The overall fraction of woody cover of 60-70% reflects significantly higher canopy density in the Malawi Rift than the Eastern Rift through time. The discrepancy between the two savanna types originated in the Late Pliocene, when the Somali-Masai ecosystem started to show increasing evidence for open, C4-dominated landscapes. Based on the Malawi δ(13)C data, the evolution of savanna ecosystems in Eastern Africa followed different patterns along the north-south extent of the EAR. The appearance of C4-grasses is considered a driver of evolutionary faunal shifts, but despite the difference of ecosystem evolution in the north, similar

  8. 21st Century African Philosophy of Adult and Human Resource Education in Southern Africa

    ERIC Educational Resources Information Center

    Mutamba, Charlene

    2012-01-01

    This paper will attempt to define a philosophy of adult education for the purpose of workforce development in Southern Africa. The different influences such as Ubuntu and communalism, indigenous education, diversity western philosophy, globalization and technology are explored in the context of the Southern African region.

  9. Population growth and environmental degradation in Malawi.

    PubMed

    Kalipeni, E

    1992-01-01

    Malawi has been ranked by the World Bank as one of the poorest countries in Africa. Malawi's only resources are its people and fertile soil, which comprises about 55% of land area. Environmental degradation and population growth conditions in Malawi were used to illustrate the model of environmental degradation linked to population pressure on land resources and government development strategies that favored large-scale agricultural farms. The result has been deforestation, overgrazing, overuse of land for subsistence, and increased population density. The argument was that population growth in some developing countries has been so rapid that environmental collapse is the result. The theoretical framework linking population growth, environment, and resources emphasized processes: 1) the precursor stage of underlying causes; 2) the problem phase with potential ecological and economic decline; and 3) consequences (environmental decline, reduction in food production systems, and reduction in standard of living). The precursors were identified as an agrarian society, lack of a population policy, and emphasis on large families. The problems were rapid population growth and immigration from Mozambique, which led to increased demand for trees for fuel and consequent deforestation, increased demand for arable land and consequent landlessness, increased investment in livestock and consequent overgrazing, and continued population momentum which was a financial burden to government and resulted in increased labor competition. The ecological consequences were soil erosion, degradation of vegetation, and water supply contamination and decline. Eventually, famines will occur and lead to disease, migration, deserted villages, urbanization, unemployment, ethnic conflicts, and political unrest. Population was estimated at 8.75 million in 1990, with exponential growth expected. Completed family size was 6.6 children per woman. Even replacement fertility would mean growth for 50 more

  10. Exposure to violence and psychological well-being over time in children affected by HIV/AIDS in South Africa and Malawi.

    PubMed

    Skeen, S; Macedo, A; Tomlinson, M; Hensels, I S; Sherr, L

    2016-03-01

    Many of the risk factors for violence against children are particularly prevalent in families and communities affected by HIV/AIDS. Yet, in sub-Saharan Africa, where HIV rates are high, efforts to prevent or address violence against children and its long-lasting effects are hampered by a lack of evidence. We assessed the relationship between violence exposure and mental health among HIV-affected children attending community-based organisations in South Africa (n = 834) and Malawi (n = 155, total sample n = 989) at baseline and 12-15-month follow-up. Exposure to violence in the home and in the community was high. HIV-negative children who lived with an HIV-positive person experienced most violence overall, followed by HIV-positive children. Children unaffected by HIV experienced least violence (all p < .05). Interpersonal violence in the home predicted child depression (β = 0.17, p < .001), trauma symptoms (β = 0.17, p < .001), lower self-esteem (β = -0.17, p < .001), and internalising and externalising behavioural problems (β = 0.07, p < .05), while exposure to community violence predicted trauma symptoms (β = 0.16, p < .001) and behavioural problems (β = 0.07, p < .05). Harsh physical discipline predicted lower self-esteem (β = -0.18, p < .001) and behavioural problems for children (β = 0.24, p < .001). Exposure to home (OR: 1.89, 95% CI: 1.23-2.85) and community violence predicted risk behaviour (OR: 2.39, 95% CI: 1.57-3.62). Over time, there was a decrease in depressed mood and problem behaviours, and an increase in self-esteem for children experiencing different types of violence at baseline. This may have been due to ongoing participation in the community-based programme. These data highlight the burden of violence in these communities and possibilities for programmes to include violence prevention to improve psychosocial well-being in HIV-affected children. PMID:27002770

  11. Exposure to violence and psychological well-being over time in children affected by HIV/AIDS in South Africa and Malawi

    PubMed Central

    Skeen, S.; Macedo, A.; Tomlinson, M.; Hensels, I. S.; Sherr, L.

    2016-01-01

    ABSTRACT Many of the risk factors for violence against children are particularly prevalent in families and communities affected by HIV/AIDS. Yet, in sub-Saharan Africa, where HIV rates are high, efforts to prevent or address violence against children and its long-lasting effects are hampered by a lack of evidence. We assessed the relationship between violence exposure and mental health among HIV-affected children attending community-based organisations in South Africa (n = 834) and Malawi (n = 155, total sample n = 989) at baseline and 12–15-month follow-up. Exposure to violence in the home and in the community was high. HIV-negative children who lived with an HIV-positive person experienced most violence overall, followed by HIV-positive children. Children unaffected by HIV experienced least violence (all p < .05). Interpersonal violence in the home predicted child depression (β = 0.17, p < .001), trauma symptoms (β = 0.17, p < .001), lower self-esteem (β = −0.17, p < .001), and internalising and externalising behavioural problems (β = 0.07, p < .05), while exposure to community violence predicted trauma symptoms (β = 0.16, p < .001) and behavioural problems (β = 0.07, p < .05). Harsh physical discipline predicted lower self-esteem (β = −0.18, p < .001) and behavioural problems for children (β = 0.24, p < .001). Exposure to home (OR: 1.89, 95% CI: 1.23–2.85) and community violence predicted risk behaviour (OR: 2.39, 95% CI: 1.57–3.62). Over time, there was a decrease in depressed mood and problem behaviours, and an increase in self-esteem for children experiencing different types of violence at baseline. This may have been due to ongoing participation in the community-based programme. These data highlight the burden of violence in these communities and possibilities for programmes to include violence prevention to improve psychosocial well-being in HIV-affected children. PMID:27002770

  12. Emigration and development in Southern Africa, with special reference to Lesotho.

    PubMed

    Cobbe, J

    1982-01-01

    "The introduction defines development and describes the scope of the paper. Section two briefly describes the historical evolution of [labor] migration in southern Africa, the ambiguities of data, and recent quantitative trends. Section three discusses alternative theoretical perspectives. Section four examines the case of Lesotho as an extreme example of a sending country and provides occasional allusions to other southern African sending countries. Section five concludes that the most important effect of [labor] migration on development in southern Africa has been to trade short run income benefits for long run development difficulties." PMID:12265313

  13. Post Rift Evolution of the Indian Margin of Southern Africa

    NASA Astrophysics Data System (ADS)

    Baby, Guillaume; Guillocheau, François; Robin, Cécile; Dall'asta, Massimo

    2016-04-01

    The objective of this study is to discuss the evolution of the South African Plateau along the Indian margin of Southern Africa. Since the classical works of A. du Toit and L.C. King and the improvement of thermochronological methods and numerical models, the question of the uplift of South African Plateau was highly debated with numerous scenarios: early Cretaceous at time of rifting (Van der Beek et al., J.Geophys.Res., 2002), late Cretaceous (Braun et al., Solid Earth, 2014), late Cenozoic (Burke & Gunnell, Geol.Soc.of America, 2008). Limited attention has been paid on the constraints provided by the offshore stratigraphic record of the surrounding margins. The objective of our study is to integrate onshore and offshore data (seismic profiles and industrial wells) to (1) analyse the infill of the whole margin (21°S to 31°S) from its hinterland to the distal deep water basin, (2) to constrain and quantify the vertical movements. We discuss the impact on accommodation and sediments partitioning, and their significance on South African Plateau uplift history. 1. Sedimentary basins of the Indian margin of Southern Africa are related to the break-up of Gondwana during late Jurassic, resulting in rifts and flexural basins. First marine incursions started during early Cretaceous times (oldest marine outcropping sediments are of Barremian age ~128 Ma). The region developed as a normal continental shelf at the Aptian-Albian transition (~113 Ma). 2. The Cretaceous geological history of the basins is characterized by differential uplift and subsidence of the basement, controlled by structures inherited from break up. As example, major early Cretaceous depocenters of the margin are located on the north of Save-Limpopo uplift (Forster, Paleogography, Paleoclimatology, Paleoecology, 1975) showing an eastward drainage pattern, maybe related to a proto Limpopo drainage. Those observations suggest that the escarpment bordering the Bushveld depression is an old relief inherited

  14. Carbon Monoxide Distributions and Atmosphere Transports over Southern Africa. Pt-2

    NASA Technical Reports Server (NTRS)

    Garstang, Michael; Swap, Robert J.; Piketh, Stuart; Mason, Simon; Connors, Vickie

    1999-01-01

    Sources and transports of CO as measured by the Measurement of Air Pollution from Space (MAPS) over a substantial sector of the southern hemisphere between South America and southern Africa are described by air parcel trajectories based upon European Center for Medium Range Weather Forecasts (ECMWF) model data fields. Observations, made by NASA Shuttle astronauts during the October 1994 mission, of vegetation fires suggest a direct relationship between in situ biomass burning, at least over South America and southern Africa, and coincident tropospheric measurements of CO. Results of this paper indicate that the transport of CO from the surface to the levels of maximum MAPS sensitivity (about 450 hPa) over these regions is not of a direct nature due largely to the well stratified atmospheric environment. The atmospheric transport of CO from biomass burning within this region is found to occur over intercontinental scales over numbers of days to more than a week. Three distinct synoptic circulation and transport classes are found to have occurred over southern Africa during the October 1994 MAPS experiment: (1) transport from South America and Africa to southern Africa associated with elevated MAPS measured CO (> 150 ppbv); (2) weakening anticyclonic transport from South America associated with moderate CO (< 150 ppbv and > 105 ppbv); and (3) transport from the high southern latitudes associated with low CO (<105 ppbv).

  15. Cape diversification and repeated out-of-southern-Africa dispersal in paper daisies (Asteraceae-Gnaphalieae).

    PubMed

    Bergh, Nicola G; Linder, H Peter

    2009-04-01

    The large daisy tribe Gnaphalieae occurs in extra-tropical habitats worldwide, but is most diverse in southern Africa and in Australia. We explore the age and evolutionary history of the tribe by means of a phylogenetic hypothesis based on Bayesian analysis of plastid and nuclear DNA sequences, maximum likelihood reconstruction of ancestral areas, and relaxed Bayesian dating. Early diversification occurred in southern Africa in the Eocene-Oligocene, resulting in a grade of mostly Cape-centred lineages which subsequently began speciating in the Miocene, consistent with diversification times for many Cape groups. Gnaphalieae from other geographic regions are embedded within a southern African paraphylum, indicating multiple dispersals out of southern Africa since the Oligocene to Miocene which established the tribe in the rest of the world. Colonisation of Australia via direct long-distance trans-oceanic dispersal in the Miocene resulted in the radiation which produced the Australasian gnaphalioid flora. The similarly diverse regional gnaphalioid floras of Australasia and southern Africa thus exhibit very different temporal species accumulation histories. An examination of the timing and direction of trans-Indian Ocean dispersal events in other angiosperms suggests a role for the West Wind Drift in long-distance dispersal eastwards from southern Africa. PMID:18822381

  16. Prognosis of Children with HIV-1 Infection Starting Antiretroviral Therapy in Southern Africa: A Collaborative Analysis of Treatment Programs

    PubMed Central

    Davies, Mary-Ann; May, Margaret; Bolton-Moore, Carolyn; Chimbetete, Cleophas; Eley, Brian; Garone, Daniela; Giddy, Janet; Moultrie, Harry; Ndirangu, James; Phiri, Sam; Rabie, Helena; Technau, Karl; Wood, Robin; Boulle, Andrew; Egger, Matthias; Keiser, Olivia

    2014-01-01

    Background Prognostic models for children starting antiretroviral therapy (ART) in Africa are lacking. We developed models to estimate the probability of death during the first year receiving ART in Southern Africa. Methods We analyzed data from children ≤10 years old who started ART in Malawi, South Africa, Zambia or Zimbabwe from 2004–2010. Children lost to follow-up or transferred were excluded. The primary outcome was all-cause mortality in the first year of ART. We used Weibull survival models to construct two prognostic models: one with CD4%, age, WHO clinical stage, weight-for-age z-score (WAZ) and anemia and one without CD4%, because it is not routinely measured in many programs. We used multiple imputation to account for missing data. Results Among 12655 children, 877 (6.9%) died in the first year of ART. 1780 children were lost to follow-up/transferred and excluded from main analyses; 10875 children were included. With the CD4% model probability of death at 1 year ranged from 1.8% (95% CI: 1.5–2.3) in children 5–10 years with CD4% ≥10%, WHO stage I/II, WAZ ≥−2 and without severe anemia to 46.3% (95% CI: 38.2–55.2) in children <1 year with CD4% <5%, stage III/IV, WAZ< −3 and severe anemia. The corresponding range for the model without CD4% was 2.2% (95% CI: 1.8–2.7) to 33.4% (95% CI: 28.2–39.3). Agreement between predicted and observed mortality was good (C-statistics=0.753 and 0.745 for models with and without CD4% respectively). Conclusion These models may be useful to counsel children/caregivers, for program planning and to assess program outcomes after allowing for differences in patient disease severity characteristics. PMID:24378936

  17. Sources of Information on HIV and Sexual and Reproductive Health for Couples Living with HIV in Rural Southern Malawi

    PubMed Central

    Gombachika, Belinda Chimphamba; Chirwa, Ellen; Malata, Address; Maluwa, Alfred

    2013-01-01

    With wider access to antiretroviral therapy, people living with HIV are reconsidering their reproductive decisions: remarrying and having children. The purpose of the paper is to explore sources of information for reproductive decision used by couples living with HIV in patrilineal and matrilineal districts of Malawi. Data were collected from forty couples from July to December 2010. Our results illuminate five specific issues: some of the informants (1) remarry after divorce/death of a spouse, (2) establish new marriage relationship with spouses living with HIV, and (3) have children hence the need for information to base their decisions. There are (4) shared and interactive couple decisions, and (5) informal networks of people living with HIV are the main sources of information. In addition, in matrilineal community, cultural practices about remarriage set up structures that constrained information availability unlike in patrilineal community where information on sexual and reproductive health, HIV, and AIDS was disseminated during remarriage counselling. However, both sources are not able to provide comprehensive information due to complexity and lack of up to date information. Therefore, health workers should, offer people living with HIV comprehensive information that takes into consideration the cultural specificity of groups, and empower already existing and accepted local structures with sexual and reproductive health, HIV, and AIDS knowledge. PMID:23662206

  18. Sources of Information on HIV and Sexual and Reproductive Health for Couples Living with HIV in Rural Southern Malawi.

    PubMed

    Gombachika, Belinda Chimphamba; Chirwa, Ellen; Malata, Address; Maluwa, Alfred

    2013-01-01

    WITH WIDER ACCESS TO ANTIRETROVIRAL THERAPY, PEOPLE LIVING WITH HIV ARE RECONSIDERING THEIR REPRODUCTIVE DECISIONS: remarrying and having children. The purpose of the paper is to explore sources of information for reproductive decision used by couples living with HIV in patrilineal and matrilineal districts of Malawi. Data were collected from forty couples from July to December 2010. Our results illuminate five specific issues: some of the informants (1) remarry after divorce/death of a spouse, (2) establish new marriage relationship with spouses living with HIV, and (3) have children hence the need for information to base their decisions. There are (4) shared and interactive couple decisions, and (5) informal networks of people living with HIV are the main sources of information. In addition, in matrilineal community, cultural practices about remarriage set up structures that constrained information availability unlike in patrilineal community where information on sexual and reproductive health, HIV, and AIDS was disseminated during remarriage counselling. However, both sources are not able to provide comprehensive information due to complexity and lack of up to date information. Therefore, health workers should, offer people living with HIV comprehensive information that takes into consideration the cultural specificity of groups, and empower already existing and accepted local structures with sexual and reproductive health, HIV, and AIDS knowledge. PMID:23662206

  19. The Changing Roles of Non-Governmental Organisations in Education in Malawi.

    ERIC Educational Resources Information Center

    Kadzamira, Esme Chipo; Kunje, Demis

    A study was commissioned by the United States Agency for International Development (USAID), Bureau for Africa, to investigate the changing roles of nongovernmental organizations (NGOs) in basic education in Africa. This Malawi case study was conducted by the Centre for Educational Research and Training of the University of Malawi. Information for…

  20. "When I Grow up I Would Like to Be …": Factors Affecting Career Choice of Community Disability Workers in Southern Africa

    ERIC Educational Resources Information Center

    Rule, Sarah; Kahonde, Callista; Lorenzo, Theresa

    2015-01-01

    The effectiveness of community based rehabilitation (CBR) programmes depends on the calibre of staff recruited and employed. Therefore, this study aimed to understand how the life experiences of community disability workers (CDWs) in Malawi, Botswana and South Africa influenced their choice of career. A life history approach was used to gather…

  1. New mineralogical and chemical data on the Machinga (L6) chondrite, Malawi

    NASA Technical Reports Server (NTRS)

    Koeberl, Christian; Reimold, Wolf Uwe; Horsch, Hanna E.; Merkle, Roland K. W.

    1990-01-01

    The Machinga, southern Malawi, Africa, L6 chondrite (observed fall, January 22, 1981) contains accessory phases of metal, troilite, chromite, and native Cu (which is associated with limonite and found in zones of aqueous alteration). Rare accessory phases are apatite and pentlandite, which are uncommon in L6 chondrites. Major mineral constituents (olivine, orthopyroxene, and plagioclase) indicate shock effects at a level of about 15-20 GPa shock pressure. The meteorite is thus classified to be of L6d type. Melt pockets of widely variable composition are abundant.

  2. A lithofacies terrain model for the Blantyre Region: Implications for the interpretation of palaeosavanna depositional systems and for environmental geology and economic geology in southern Malawi

    NASA Astrophysics Data System (ADS)

    Dill, H. G.; Ludwig, R.-R.; Kathewera, A.; Mwenelupembe, J.

    2005-06-01

    The Blantyre City Area is part of the African savanna in southern Malawi. Sedimentological, geomorphological, chemical and mineralogical studies were conducted to create a lithofacies terrain model. The project involves mapping, cross-sectioning, grain size, heavy mineral analysis, XRD and the study of sedimentary textures under the petrographic microscope. These classical techniques were combined with GIS-based field and office works. The combined efforts led to 2-D maps and 3-D block diagrams that illustrate the geomorphological and sedimentological evolution of the landscape in southern Malawi during the late Mesozoic and Cenozoic. The results obtained through integrated geomorphological-sedimentological studies form the basis for land management (planning of residential areas, waste disposal sites, assessment of bearing capacity of rocks), geohazard prediction (delineation of high risk zones in terms of mass flow and inundation) and the evaluation of high-place (ceramic raw materials) and high-unit value (placers of precious metals and gemstones) mineral commodities in the study area. The study addresses regional and general aspects alike. In regional terms, the study aimed at unraveling the evolution of landforms at the southern end of the East African Rift System during the most recent parts of the geological past. Four stages of peneplanation were established in the working area. Planation was active from the Cretaceous to the Quaternary (stage I: early to mid-Cretaceous, stage II: early Tertiary, stage III: early to mid-Tertiary, stage IV: mid- to late Tertiary). During the most recent parts of the Quaternary, strong fluvial incision was triggered by the base-level lowering of the Shire River. Geomorphological alteration of the landscape goes along with a phyllosilicate-sesquioxide transformation from minerals indicative of more acidic meteoric fluids (e.g., gibbsite, kaolinite) to those typical of more alkaline conditions (e.g. smectite, vermiculite

  3. Tropospheric Ozone Increases over the Southern Africa Region: Bellwether for Rapid Growth in Southern Hemisphere Pollution?

    NASA Technical Reports Server (NTRS)

    Thompson, Anne M.; Balashov, Nikolay V.; Witte, J. C.; Coetzee, J. G. R.; Thouret, V.; Posny, F.

    2014-01-01

    Increases in free-tropospheric (FT) ozone based on ozonesonde records from the early 1990s through 2008 over two subtropical stations, Irene (near Pretoria, South Africa) and Réunion (21 deg. S, 55 deg. E; approx. 2800 km NE of Irene in the Indian Ocean), have been reported. Over Irene a large increase in the urban-influenced boundary layer (BL, 1.5-4 km) was also observed during the 18-year period, equivalent to 30%decade-1. Here we show that the Irene BL trend is at least partly due to a gradual change in the sonde launch times from early morning to the midday period. The FT ozone profiles over Irene in 1990-2007 are re-examined, filling in a 1995-1999 gap with ozone profiles taken during the Measurements of Ozone by Airbus In-service Aircraft (MOZAIC) project over nearby Johannesburg. A multivariate regression model that accounts for the annual ozone cycle, El Niño-Southern Oscillation (ENSO) and possible tropopause changes was applied to monthly averaged Irene data from 4 to 11 km and to 1992-2011 Réunion sonde data from 4 to 15 km. Statistically significant trends appear predominantly in the middle and upper troposphere (UT; 4-11 km over Irene, 4-15 km over Réunion) in winter (June-August), with increases 1 ppbv yr(exp. -1) over Irene and approx. 2 ppbv yr(exp. -1) over Réunion. These changes are equivalent to approx. 25 and 35-45%decade( exp. -1), respectively. Both stations also display smaller positive trends in summer, with a 45%decade(exp. -1) ozone increase near the tropopause over Réunion in December. To explain the ozone increases, we investigated a time series of dynamical markers, e.g., potential vorticity (PV) at 330-350 K. PV affects UT ozone over Irene in November-December but displays little relationship with ozone over Réunion. A more likely reason for wintertime FT ozone increases over Irene and Réunion appears to be long-range transport of growing pollution in the Southern Hemisphere. The ozone increases are consistent with trajectory

  4. Tropospheric ozone increases over the southern Africa region: bellwether for rapid growth in Southern Hemisphere pollution?

    NASA Astrophysics Data System (ADS)

    Thompson, A. M.; Balashov, N. V.; Witte, J. C.; Coetzee, J. G. R.; Thouret, V.; Posny, F.

    2014-09-01

    Increases in free-tropospheric (FT) ozone based on ozonesonde records from the early 1990s through 2008 over two subtropical stations, Irene (near Pretoria, South Africa) and Réunion (21° S, 55° E; ~2800 km NE of Irene in the Indian Ocean), have been reported. Over Irene a large increase in the urban-influenced boundary layer (BL, 1.5-4 km) was also observed during the 18-year period, equivalent to 30% decade-1. Here we show that the Irene BL trend is at least partly due to a gradual change in the sonde launch times from early morning to the midday period. The FT ozone profiles over Irene in 1990-2007 are re-examined, filling in a 1995-1999 gap with ozone profiles taken during the Measurements of Ozone by Airbus In-service Aircraft (MOZAIC) project over nearby Johannesburg. A multivariate regression model that accounts for the annual ozone cycle, El Niño-Southern Oscillation (ENSO) and possible tropopause changes was applied to monthly averaged Irene data from 4 to 11 km and to 1992-2011 Réunion sonde data from 4 to 15 km. Statistically significant trends appear predominantly in the middle and upper troposphere (UT; 4-11 km over Irene, 4-15 km over Réunion) in winter (June-August), with increases ~1 ppbv yr-1 over Irene and ~2 ppbv yr-1 over Réunion. These changes are equivalent to ~25 and 35-45% decade-1, respectively. Both stations also display smaller positive trends in summer, with a 45% decade-1 ozone increase near the tropopause over Réunion in December. To explain the ozone increases, we investigated a time series of dynamical markers, e.g., potential vorticity (PV) at 330-350 K. PV affects UT ozone over Irene in November-December but displays little relationship with ozone over Réunion. A more likely reason for wintertime FT ozone increases over Irene and Réunion appears to be long-range transport of growing pollution in the Southern Hemisphere. The ozone increases are consistent with trajectory origins of air parcels sampled by the sondes and

  5. Comparison of Interglacial fire dynamics in Southern Africa

    NASA Astrophysics Data System (ADS)

    Brücher, Tim; Daniau, Anne-Laure

    2016-04-01

    Responses of fire activity to a change in climate are still uncertain and biases exist by integrating this non-linear process into global modeling of the Earth system. Warming and regional drying can force fire activity in two opposite directions: an increase in fire in fuel supported ecosystems or a fire reduction in fuel-limited ecosystems. Therefore, climate variables alone can not be used to estimate the fire risk because vegetation variability is an important determinant of fire dynamics and responds itself to change in climate. Southern Africa (south of 20°S) paleofire history reconstruction obtained from the analysis of microcharcoal preserved in a deep-sea core located off Namibia reveals changes of fire activity on orbital timescales in the precession band. In particular, increase in fire is observed during glacial periods, and reduction of fire during interglacials such as the Eemian and the Holocene. The Holocene was characterized by even lower level of fire activity than Eemian. Those results suggest the alternance of grass-fueled fires during glacials driven by increase in moisture and the development of limited fueled ecosystems during interglacials characterized by dryness. Those results question the simulated increase in the fire risk probability projected for this region under a warming and drying climate obtained by Pechony and Schindell (2010). To explore the validity of the hypotheses we conducted a data-model comparison for both interglacials from 126.000 to 115.000 BP for the Eemian and from 8.000 to 2.000 BP for the Holocene. Data out of a transient, global modeling study with a Vegetation-Fire model of full complexity (JSBACH) is used, driven by a Climate model of intermediate complexity (CLIMBER). Climate data like precipitation and temperature as well as vegetation data like soil moisture, productivity (NPP) on plant functional type level are used to explain trends in fire activity. The comparison of trends in fire activity during the

  6. Moho depth and crustal composition in Southern Africa

    NASA Astrophysics Data System (ADS)

    Youssof, M.; Thybo, H.; Artemieva, I. M.; Levander, A.

    2013-12-01

    We present new results on structure, thickness, and composition of the crust in southern Africa based on 6300 seismic receiver functions at 85 stations. Application of Hk-stacking to the entire SASE dataset and use of multi-frequency bands improve resolution substantially. We observe a highly heterogeneous crustal structure with short wavelength variations in thickness (H), Vp/Vs-ratio (composition), and Moho sharpness, which defines ~ 20 blocks that do not everywhere coincide with surface tectonic features. In the Zimbabwe Craton, the Tokwe block has H = 35-38 km and Vp/Vs = 1.74-1.79 whereas the thicker crust in the Tati block (H = 47-51 km) may be related to deformation of the Archean crust along the cratonic margin. Two distinct crustal blocks with similar crustal thickness (42-46 km) but significantly different Vp/Vs-ratios are recognized in the Limpopo Belt. Extreme values of 1.90-1.94 at the dyke swarms in eastern Limpopo, and 1.84 at the Olifants River Dyke Swarm and easternmost Bushveld Intrusion Complex (BIC) indicate voluminous magmatic intrusions in the whole crust. We find no evidence for magmatic intrusions in the central (inferred) part of BIC, where the crust is thick (45-50 km) and Vp/Vs is low (1.68-1.70). This thick crustal root may have deflected rising magmas to form the two BIC lobes. Most of central Kaapvaal has thin (35-40 km) crust and Vp/Vs ~ 1.74. These characteristics are similar to the Tokwe block in Zimbabwe Craton and may indicate delamination of pre-existing lower crust, which is further supported by a very sharp Moho transition. The exposed cross-section in the Vredefort impact crater is non-representative of cratonic crust due to shallow Moho (34 km) and high Vp/Vs ~ 1.80 attributed to shock metamorphism. High Vp/Vs = 1.76 is typical of the Witwatersrand Basin, and anomalously low Vp/Vs = 1.66-1.67 marks the Kaapvaal-Kheis-Namaqua transition. Highly heterogeneous crust, both in thickness and Vp/Vs-ratio is typical of the Namaqua

  7. THE WEIGHT OF SUCCESS: THE BODY MASS INDEX AND ECONOMIC WELL-BEING IN SOUTHERN AFRICA

    PubMed Central

    Wittenberg, Martin

    2015-01-01

    We show that body mass increases with economic resources among most Southern Africans, although not all. Among Black South Africans the relationship is non-decreasing over virtually the entire range of incomes/wealth. Furthermore in this group other measures of “success” (e.g., employment and education) are also associated with increases in body mass. This is true in both 1998 (the Demographic and Health Survey) and 2008 (National Income Dynamics Survey). A similar relationship holds among residents of Lesotho, Swaziland, Mozambique, Malawi, and Namibia. This suggests that body mass can be used as a crude measure of well-being. This allows us to examine the vexed question in South African labor economics whether there is involuntary unemployment. The fact that the unemployed are lighter than the employed, even when we control for household fixed effects, suggests that they are not choosing this state. PMID:26199456

  8. ERTS imagery as a source of environmental information for southern Africa

    NASA Technical Reports Server (NTRS)

    Williamson, D. T.; Gilbertson, B.

    1974-01-01

    Southern Africa is faced with a variety of environmental problems that reflect the different states of development of countries in the region. The task of the environmental planner is in many instances complicated by a lack of basic resource information. The acquisition of the necessary data is often impeded by shortage of trained personnel and lack of funds, particularly in developing nations of the region. The range of environmental problems in Southern Africa are described and specific examples are shown of how ERTS type imagery can materially assist in solving these problems. These examples demonstrate that ERTS type data will be of substantial value to both the industrialized and the developing nations of Southern Africa, provided that problems of availability and user education are overcome.

  9. Lead Toxicosis in a Southern Ground Hornbill Bucorvus leadbeateri in South Africa.

    PubMed

    Koeppel, Katja N; Kemp, Lucy V

    2015-12-01

    The southern ground hornbill (Bucorvus leadbeateri) has been classified as globally vulnerable and, in South Africa, regionally endangered, with a negative population trend. Factors contributing to the population decline in South Africa are poisoning, electrocution, and illegal capture for trade, coupled with slow reproductive rates and extensive habitat requirements. Lead toxicosis is a previously undescribed threat for the population. An adult southern ground hornbill presented with acute lead toxicosis due to lead particles in the gizzard, which required intensive treatment. Two other hornbills were likely exposed. The source of the lead in these cases was likely a carcass of a porcupine that was killed with lead shot. This report highlights the importance of the use of lead-free ammunition within the habitat of the southern ground hornbill in South Africa. PMID:26771324

  10. Shear wave velocity structure of the southern African upper mantle with implications for the uplift of southern Africa

    NASA Astrophysics Data System (ADS)

    Adams, Aubreya; Nyblade, Andrew

    2011-08-01

    Broad-band seismic data from the southern African seismic experiment and the AfricaArray network are used to investigate the seismic velocity structure of the upper mantle beneath southern Africa, and in particular beneath the Kaapvaal Craton. A two-plane approximation method that includes a finite frequency sensitivity kernel is employed to measure Rayleigh wave phase velocities, which are inverted to obtain a quasi-3-D shear wave velocity model of the upper mantle. We find phase velocities for the Kaapvaal Craton and surrounding mobile belts that are comparable to those reported by previous studies, and we find little evidence for variation from east to west across the Namaqua-Natal Belt, a region not well imaged in previous studies. A high-velocity upper-mantle lid is found beneath the Kaapvaal Craton and most of southern Africa. For the Kaapvaal Craton, the thickness of the lid (˜150-200 km) is consistent with the lid thicknesses reported in many previous studies. The cratonic lid is underlain by a ˜100-km thick low-velocity zone with a 3.9 per cent maximum velocity reduction. By comparing the velocity model to those published for other Archean cratons, we find few differences, and therefore conclude that there is little evidence in the shear wave velocity structure of the mantle to indicate that the southern African plateau is supported by an upper-mantle thermal anomaly.

  11. Evaluating environmental and social influences on iron and zinc status of pregnant subsistence farmers in two geographically contrasting regions of Southern Malawi.

    PubMed

    Dickinson, N; Rankin, J; Pollard, M; Maleta, K; Robertson, C; Hursthouse, A

    2014-12-01

    Micronutrient deficiency affects over 4.5 billion people worldwide, the majority in developing countries. Deficiencies of iron (and associated anaemia) and zinc in pregnancy are associated with complications, maternal and neonatal mortality, and developmental disorders in the foetus and growing child. We report the results of pilot study which used an interdisciplinary approach to explore environmental and sociocultural factors influencing the micronutrient status in the soil-plant-human transfer for pregnant subsistence farmers in two geographically contrasting regions of Southern Malawi. It evaluated micronutrient status in soil and the staple crop and explored the context for their transfer to pregnant women. Scientific and social science methods were used to collect data, following full sensitisation of the communities. A total of 99 participants were recruited from Chiradzulu (plateau) and Chikwawa (floodplain). Soil, maize and blood samples were collected, along with food frequency and health behaviour questionnaires and anthropological observation. Statistical analysis revealed that soil iron was significantly higher in Chiradzulu than in Chikwawa; total iron concentration is not deemed to be deficient in either area. Soil zinc was not significantly different between areas. Maize concentrations of iron and zinc were not significantly different between areas, and were not deficient relative to improved cultivars. Blood iron deficiency and associated anaemia were problematic in both areas, but more so in Chikwawa than in Chiradzulu, and zinc deficiency was similar in both areas. The study has identified a significant difference in the blood iron status of the participants of the two communities, and has shown that this difference is not accounted for by the staple crop maize. Socio-geographical factors appear to play a significant role in the micronutrient health of the populations. The findings lend support to multifaceted community intervention studies which

  12. Key Issues in Library and Information Science for Southern Africa: A Handbook for Library and Information Specialists.

    ERIC Educational Resources Information Center

    Mncube, Stephen Sipho

    Designed to provide a conceptual and workable framework for the development of interdisciplinary information systems in Southern Africa, this handbook focuses on Southern Africa's information needs and addresses the problems between theory and practice in information transfer and utilization. The handbook is divided into two major parts. The four…

  13. Modulation of the Southern Africa precipitation response to the El Niño Southern Oscillation by the subtropical Indian Ocean Dipole

    NASA Astrophysics Data System (ADS)

    Hoell, Andrew; Funk, Chris; Zinke, Jens; Harrison, Laura

    2016-06-01

    The climate of Southern Africa, defined as the land area bound by the region 15°S-35°S; 12.5°E-42.5°E, during the December-March rainy season is driven by Indo-Pacific sea surface temperature (SST) anomalies associated with the El Niño Southern Oscillation (ENSO) and the Subtropical Indian Ocean Dipole (SIOD). The observed December-March 1979-2014 Southern Africa precipitation during the four ENSO and SIOD phase combinations suggests that the phase of the SIOD can disrupt or enhance the Southern Africa precipitation response to ENSO. Here, we use a large ensemble of model simulations driven by global SST and ENSO-only SST to test whether the SIOD modifies the relationship between Southern Africa precipitation and ENSO. Since ENSO-based precipitation forecasts are used extensively over Southern Africa, an improved understanding of how other modes of SST variability modulate the regional response to ENSO is important. ENSO, in the absence of the SIOD, forces an equivalent barotropic Rossby wave over Southern Africa that modifies the regional mid-tropospheric vertical motions and precipitation anomalies. El Niño (La Niña) is related with high (low) pressure over Southern Africa that produces anomalous mid-tropospheric descent (ascent) and decreases (increases) in precipitation relative to average. When the SIOD and ENSO are in opposite phases, the SIOD compliments the ENSO-related atmospheric response over Southern Africa by strengthening the regional equivalent barotropic Rossby wave, anomalous mid-tropospheric vertical motions and anomalous precipitation. By contrast, when the SIOD and ENSO are in the same phase, the SIOD disrupts the ENSO-related atmospheric response over Southern Africa by weakening the regional equivalent barotropic Rossby wave, anomalous mid-tropospheric vertical motions and anomalous precipitation.

  14. Dust from southern Africa: rates of emission and biogeochemical properties

    NASA Astrophysics Data System (ADS)

    Bhattachan, A.; D'Odorico, P.; Zobeck, T. M.; Okin, G. S.; Dintwe, K.

    2012-12-01

    The stabilized linear dunefields in the southern Kalahari show signs of reactivation due to reduced vegetation cover owing to drought and/or overgrazing. It has been demonstrated with a laboratory dust generator that the southern Kalahari soils are good emitters of dust and that large-scale dune reactivation can potentially make the region an important dust source in the relatively low-dust Southern Hemisphere. We show that emergence of the southern Kalahari as a new dust source may affect ocean biogeochemistry as the soils are rich in soluble iron and the dust from the southern Kalahari commonly reaches the Southern Ocean. We investigate the biogeochemical properties of the fine fraction of soil from the Kalahari dunes and compare them to those of currently active dust sources such as the Makgadikgadi and the Etosha pans as well as other smaller pans in the region. Using field measurements of sediment fluxes and satellite images, we calculate the rates of dust emission from the southern Kalahari under different land cover scenarios. To assess the reversibility of dune reactivation in the southern Kalahari, we investigate the resilience of dunefield vegetation by looking at changes in soil nutrients, fine soil fractions, and seed bank in areas affected by intense denudation.

  15. Dust from southern Africa: rate of emission and biogeochemical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The stabilized linear dunefields in the southern Kalahari show signs of reactivation due to reduced vegetation cover owing to drought and/or overgrazing. It has been demonstrated with a laboratory dust generator that the southern Kalahari soils are good emitters of dust and that large-scale dune rea...

  16. Simulating the link between ENSO and summer drought in Southern Africa using regional climate models

    NASA Astrophysics Data System (ADS)

    Meque, Arlindo; Abiodun, Babatunde J.

    2015-04-01

    This study evaluates the capability of regional climate models (RCMs) in simulating the link between El Niño Southern Oscillation (ENSO) and Southern African droughts. It uses the Standardized Precipitation-Evapotranspiration Index (SPEI, computed using rainfall and temperature data) to identify 3-month drought over Southern Africa, and compares the observed and simulated correlation between ENSO and SPEI. The observation data are from the Climate Research Unit, while the simulation data are from ten RCMs (ARPEGE, CCLM, HIRHAM, RACMO, REMO, PRECIS, RegCM3, RCA, WRF, and CRCM) that participated in the regional climate downscaling experiment (CORDEX) project. The study analysed the rainy season (December-February) data for 19 years (1989-2008). The results show a strong link between ENSO and droughts (SPEI) over Southern Africa. The link is owing to the influence of ENSO on both rainfall and temperature fields, but the correlation between ENSO and temperature is stronger than the correlation between ENSO and rainfall. Hence, using only rainfall to monitor droughts in Southern Africa may underestimate the influence of ENSO on the droughts. Only few CORDEX RCMs simulate the influence of ENSO on Southern African drought as observed. In this regard, the ARPEGE model shows the best simulation, while CRCM shows the worst. The different in the performance may be due to their lateral boundary conditions. The RCA-simulated link between ENSO and Southern African droughts is sensitive to the global dataset used as the lateral boundary conditions. In some cases, using RCA to downscale global circulation models (GCM) simulations adds value to the simulated link between ENSO and the droughts, but in other cases the downscaling adds no value to the link. The added value of RCA to the simulated link decreases as the capability of the GCM to simulate the link increases. This study suggests that downscaling GCM simulations with RCMs over Southern Africa may improve or depreciate the

  17. Patterns of stress and strain rate in southern Africa

    NASA Astrophysics Data System (ADS)

    Bird, Peter; Ben-Avraham, Zvi; Schubert, Gerald; Andreoli, Marco; Viola, Giulio

    2006-08-01

    The southward propagation of the East Africa rift presents an opportunity to study plate boundary formation. We tabulate orientation data which confirm the province of NW-SE directed most compressive horizontal principal stress ("Wegener stress anomaly") earlier tentatively attributed to ridge push. We also collect information on stress "regime," described by the associated Andersonian fault type(s). We use thin shell finite element models with realistic rheology to test three causes of stress: (1) lateral variations in density moment, (2) resistance of unbroken lithosphere to relative plate rotation, and (3) stress concentration ahead of a crack tip. Models with stress due primarily to variations in density moment are unsuccessful in their predictions (59-73% incorrect regimes; 32-40° azimuth errors). Models in which Africa-Somalia spreading is regulated at realistic rates by remote boundary conditions are more accurate (18-41% incorrect regimes; 25-35° azimuth errors). Treating the East Africa rift as a frictionless crack degrades the fit in either case. Apparently, the Wegener stress anomaly is caused primarily by resistance to the relative rotation between the Somalia and Africa plates. The East Africa rift north of 21°S may be weakened by strain but has residual friction ≥0.1. Greater strength of oceanic lithosphere is likely to cause stress increases, reorientations, and regime changes offshore. The predicted strain rate map has high rates along the rift, curving at 12°S into a western arc through Angola-Namibia-South Africa. Seismic hazard in Namibia may be greater than the instrumental catalog suggests. However, a number of unfit data indicate that these models represent only a first step.

  18. Tamarix (Tamaricaceae) hybrids: most dominant invasive genotype in southern Africa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybridization can potentially enhance invasiveness. Tamarix (Tamaricaceae) hybrids appear to be the dominant genotypes in their invasions. Exotic Tamarix are declared invasive in South Africa and the exotic T. chinensis and T. ramosissima are known to hybridize between themselves, and with the nativ...

  19. Novel Arenavirus Isolates from Namaqua Rock Mice, Namibia, Southern Africa

    PubMed Central

    Kallies, René; Hoveka, Julia; Auste, Brita; Ithete, Ndapewa L.; Šoltys, Katarína; Szemes, Tomáš; Drosten, Christian; Preiser, Wolfgang; Klempa, Boris; Mfune, John K.E.; Kruger, Detlev H.

    2015-01-01

    Arenaviruses are feared as agents that cause viral hemorrhagic fevers. We report the identification, isolation, and genetic characterization of 2 novel arenaviruses from Namaqua rock mice in Namibia. These findings extend knowledge of the distribution and diversity of arenaviruses in Africa. PMID:26079174

  20. Delivering Lifelong Learning for Sustainable Development in Southern Africa: Problems and Prospects

    ERIC Educational Resources Information Center

    Maruatona, Tonic L.

    2012-01-01

    Southern African Development Community (SADC) nations in principle endorse lifelong learning (LLL) as a useful framework for sustainable development. However, in spite of the rhetoric, only a few member states such as South Africa, Botswana and Namibia have officially endorsed LLL in their educational policies. The sub-region is plagued by social…

  1. Language Choice and Education Quality in Eastern and Southern Africa: A Review

    ERIC Educational Resources Information Center

    Trudell, Barbara

    2016-01-01

    In 2014, UNICEF commissioned a review of language policy and education quality in the 21 countries of UNICEF's Eastern and Southern Africa Region. This paper examines findings from the review, related to the role of English and local languages in current education practice in the region. National language policies and implementation practices are…

  2. Can Inclusive Education in South(ern) Africa Survive the HIV and AIDS Pandemic?

    ERIC Educational Resources Information Center

    Beyers, Christa; Hay, Johnnie

    2007-01-01

    Fagan (1986, p. 859) stated many years ago that "school psychology has survived the complex interaction between education and psychology, and will continue to do so in future". Applied and adapted to South(ern) Africa of 2007, one may ask whether inclusive education will survive the complex interaction with the HIV and AIDS pandemic, and whether…

  3. Steps Forward and New Challenges: Indigenous Communities and Mother-Tongue Education in Southern Africa

    ERIC Educational Resources Information Center

    Hays, Jennifer

    2009-01-01

    Two international conferences held in southern Africa in 2005 gathered education and language experts to discuss practical, theoretical, and political aspects of the development of African languages for education. Despite the diversity of the participants, there was unanimous agreement that the economic and social benefits of providing…

  4. Language Policy and Orthographic Harmonization across Linguistic, Ethnic and National Boundaries in Southern Africa

    ERIC Educational Resources Information Center

    Banda, Felix

    2016-01-01

    Drawing on online and daily newspapers, speakers' language and writing practices, official government documents and prescribed spelling systems in Southern Africa, the paper explores the challenges and possibilities of orthographic reforms allowing for mobility across language clusters, ethnicity, regional and national borders. I argue that this…

  5. Diffusion of the National Qualifications Framework and Outcomes-Based Education in Southern and Eastern Africa

    ERIC Educational Resources Information Center

    Chisholm, Linda

    2007-01-01

    This article explores policy and curriculum diffusion in southern and eastern Africa through an examination of the National Qualifications Framework (NQF) and outcomes-based education. The article argues that the NQF was adopted for different reasons in different contexts, but that discourse coalitions and conferences have been critical in…

  6. Lest the rhetoric begin: migration, population and the environment in Southern Africa.

    PubMed

    Mcdonald, D A

    1999-02-01

    In the spirited debate over cross-border migration in southern Africa there is one issue that has been conspicuously absent: the environment. The issue is raised in this article not because it necessarily deserves to be part of the debate--it will be argued, in fact that one needs to tread very carefully when drawing any linkages between migration and the environment--but because it has received an inordinate amount of attention in the academic and popular press in other parts of the world (particularly in the US) and could influence South African immigration policy and debates. In this article the authors look specifically at Thomas Homer-Dixon's influential work on environmental scarcity and migration and critically assess its relevance in the southern African context. A brief review of the history of migration and immigration policy in the region is followed by a theoretical and empirical critique of Homer Dixon's writings. It is acknowledged in the article that environmental degradation can (and does) contribute to forced migration and violent conflict in southern Africa, but it is also argued that Homer-Dixon misses some fundamental points about the political economy of (post) apartheid southern Africa and in doing so presents a very problematic interpretation of the causes and effects of migration in the region. The potential for these theories to lend themselves to a reactionary, closed-border approach to immigration in South Africa is also discussed and forms part of the impetus for the writing of this paper. PMID:12322616

  7. Comparison of TAMSAT and CPC rainfall estimates with rainfall for southern Africa

    NASA Astrophysics Data System (ADS)

    Thorne, Virginia; Coakeley, Paul; Grimes, David I. F.; Dugdale, George

    1999-12-01

    Two different TAMSAT methods of Rainfall Estimation were developed respectively for northern and southern Africa, based on Meteosat TIR images; northern Africa since 1987 and southern Africa since 1990. These rainfall estimates are used operationally for agricultural purposes and for predicting famines and floods. The two different methods have both been used to make rainfall estimates for the southern rainy season October 1995 to April 1996, and then compared with estimates produced by the CPC method. The latter are made more simply from TIR, but have the addition of GTS rainfall data and orographic rain. All these estimates were then compared with kriged data from over 800 raingauges in southern Africa. The detailed results were then compared for the whole season across the whole SADC region, and then two detailed cross- sections were studied, with different orography. The results show that operational TAMSAT estimates are better over plateau regions, with 59% estimates within 1 Std of the rainfall, but over the whole region the CPC estimates perform best. Over mountainous regions all methods under-estimate and give only 40% within 1Std. The two TAMSAT methods show little difference across a whole season, but when looked at in detail the northern method gives unsatisfactory calibrations. The CPC method does have significant overall improvements by building in real-time raingauge data, but only where sufficient raingauges are available.

  8. The Impact of the Southern and Eastern Africa Consortium for Monitoring Educational Quality (SACMEQ)

    ERIC Educational Resources Information Center

    Murimba, Saul

    2005-01-01

    Southern and Eastern Africa Consortium for Monitoring Educational Quality (SACMEQ) is fast emerging as a globally recognized initiative in the area of the monitoring and evaluation of educational quality, and the results of its research and training have not only been used within the member countries, but elsewhere too. SACMEQ has had a presence…

  9. Of Drama, Dreams and Desire: Creative Approaches to Applied Sex Education in Southern Africa

    ERIC Educational Resources Information Center

    Casale, Marisa; Hanass-Hancock, Jill

    2011-01-01

    In the midst of a generalised HIV and AIDS epidemic in southern Africa, the argument for more coordinated and comprehensive youth sexual health interventions is intensifying. Yet the crucial question of "how best" to provide young people with these skills and knowledge remains a key challenge for policy-makers, researchers and practitioners in our…

  10. Identification of widespread pollution in the southern hemisphere deduced from satellite analyses. [AFRICA

    SciTech Connect

    Fishman, J. ); Fakhruzzaman, K. ); Cros, B.; Nganga, D. )

    1991-06-21

    Vertical profiles of ozone obtained from ozonesondes in Brazzaville, Congo (4{degree}S, 15{degree}E), and Ascension Island (98{degree}S, 15{degree}W) show that large quantities of tropospheric ozone are present over southern Africa and the adjacent eastern tropical South Atlantic Ocean. The origin of this pollution is widespread biomass burning in Africa. These measurements support satellite-derived tropospheric ozone data that demonstrate that ozone originating from the region is transported throughout most of the Southern Hemisphere. Seasonally high levels of carbon monoxide and methane observed at middle- and high-latitude stations in Africa, Australia, and Antarctica likely reflect the effects of this distant biomass burning. These data suggest that even the most remote regions on this planet may be significantly more polluted than previously believed.

  11. Exploratory Long-Range Models to Estimate Summer Climate Variability over Southern Africa.

    NASA Astrophysics Data System (ADS)

    Jury, Mark R.; Mulenga, Henry M.; Mason, Simon J.

    1999-07-01

    Teleconnection predictors are explored using multivariate regression models in an effort to estimate southern African summer rainfall and climate impacts one season in advance. The preliminary statistical formulations include many variables influenced by the El Niño-Southern Oscillation (ENSO) such as tropical sea surface temperatures (SST) in the Indian and Atlantic Oceans. Atmospheric circulation responses to ENSO include the alternation of tropical zonal winds over Africa and changes in convective activity within oceanic monsoon troughs. Numerous hemispheric-scale datasets are employed to extract predictors and include global indexes (Southern Oscillation index and quasi-biennial oscillation), SST principal component scores for the global oceans, indexes of tropical convection (outgoing longwave radiation), air pressure, and surface and upper winds over the Indian and Atlantic Oceans. Climatic targets include subseasonal, area-averaged rainfall over South Africa and the Zambezi river basin, and South Africa's annual maize yield. Predictors and targets overlap in the years 1971-93, the defined training period. Each target time series is fitted by an optimum group of predictors from the preceding spring, in a linear multivariate formulation. To limit artificial skill, predictors are restricted to three, providing 17 degrees of freedom. Models with colinear predictors are screened out, and persistence of the target time series is considered. The late summer rainfall models achieve a mean r2 fit of 72%, contributed largely through ENSO modulation. Early summer rainfall cross validation correlations are lower (61%). A conceptual understanding of the climate dynamics and ocean-atmosphere coupling processes inherent in the exploratory models is outlined.Seasonal outlooks based on the exploratory models could help mitigate the impacts of southern Africa's fluctuating climate. It is believed that an advance warning of drought risk and seasonal rainfall prospects will

  12. Institutional Research in Emerging Countries of Southern Africa, Latin America, and the Middle East and North Africa: Global Frameworks and Local Practices

    ERIC Educational Resources Information Center

    Lange, Lis; Saavedra, F. Mauricio; Romano, Jeanine

    2013-01-01

    This chapter presents a synthesis of the conceptualization and practice of institutional research (IR) in higher education (HE) in emerging countries across Southern Africa, Latin America and the Middle East and North Africa (MENA) regions. The chapter contextualizes the growing need for IR in these regions, identifies problems and challenges…

  13. Drivers and Dynamics of Global Environmental Change in Southern Africa

    NASA Astrophysics Data System (ADS)

    Jewitt, Graham; Munishi, Subira; Kunz, Richard; Viola, Paula

    2010-05-01

    Africa's potential to provide food, fuel, fibre and fodder for future global food and energy security has made it a target for a myriad investors from developed and developing countries alike. In many places, land grants and purchases have led to the establishment of huge monoculture production areas for food, fuel, fibre (maize, sugar cane, jatropha, plantation forestry etc) often preceded by deforestation and large scale utilisation and modification of available water resources. This coupled with the likelihood of rapid urbanisation in Africa over the next forty years and associated impacts linked to the high concentrations of inhabitants utilising and ultimately degrading available natural resources (e.g. wood for charcoal; water quality) have made Africa's ecosystems and people amongst the most vulnerable to global environmental change. Key questions that arise are how available scientific knowledge can best be utilized to reduce this vulnerability, where key gaps in knowledge in understanding the inter-linkages between societal needs and Food- Fibre-Energy-Water supply exist and how to best address the necessary complexity of considering these at different spatial and temporal scales. Drawing on the Ecosystem Goods and Services approach, we present key messages from ongoing research activities in South Africa, Swaziland, Mozambique and Tanzania and report on progress in applying management tools and systems to support decision making in these areas where development needs are critical. We also highlight lessons drawn from situations where unintended consequences have resulted from well meaning or politically expedient initiatives linked to large donor or foreign investment schemes, such as "outgrower" programmes, and where major environmental damage and ultimately the permanent loss of productivity of some landscapes has occurred.

  14. A unified history of the ocean around southern Africa

    NASA Astrophysics Data System (ADS)

    Reeves, Colin; Master, Sharad

    2010-05-01

    The movement with respect to Africa of the hotspot marked by present-day Bouvet island is extrapolated backward in time to a position in the Lower Limpopo Valley at the time of the Karoo-Ferrar basalt event (183 Ma). In a tight reconstruction of the Precambrian fragments of Gondwana at this time, the triangular gap that remains between South Africa's Precambrian, that of Dronning Maud Land, Antarctica, and the eastward-extrapolated front of the Cape Fold Belt we fill with the Precambrian fragments of South Patagonia and the Falkland Islands. We postulate that the 183 Ma mantle upwelling produced a triple junction-type fracture marked by the alignments of the Lebombo, the SE margin of the Zimbabwe craton and the giant Botswana dyke swarm (178 Ma) that was rather quickly followed by the expulsion of the South Patagonia terranes from the Gondwana assembly along the alignment of the Falklands-Agulhas Fault Zone (FAFZ) as a transform margin. The space created was filled with igneous material akin to the present day Afar triangle. The magma supply generated not only oceanic crust but also overlying igneous deposits, much probably erupted subaerially. These developed progressively into the Falklands Plateau, the Mozambique Plains, the Mozambique Rise and the Explora Wedge of Antarctica. Not until the early Cretaceous did the growth of normal ocean crust start to exceed the ability of the declining mantle plume to cover the new ocean crust in a confined space with subaerial deposits that substantially thickened otherwise ‘oceanic' crust. When Antarctica and Africa began to separate before about 167 Ma, the future Mozambique Rise moved with Antarctica until, at about 125 Ma, a modest ridge reorganization east of Africa left Madagascar and the Mozambique Rise as part of the Africa Plate. An increasing westerly component to the movement of Antarctica against Africa preceded the initial opening of the South Atlantic and the fusing of the South Patagonia terranes with the

  15. Independent Education in Southern Africa. ISIS Document No. 33.

    ERIC Educational Resources Information Center

    Mason, Peter

    This study describes the legal status, aims, organization, resources, role and future prospects of the independent educational sector in five Southern African countries and the context in which it operates. The term "independent" schools is meant to include what traditionally have been called private schools, and also includes schools that are run…

  16. A southern Africa harmonic spline core field model derived from CHAMP satellite data

    NASA Astrophysics Data System (ADS)

    Nahayo, E.; Kotzé, P. B.; McCreadie, H.

    2015-02-01

    The monitoring of the Earth's magnetic field time variation requires a continuous recording of geomagnetic data with a good spatial coverage over the area of study. In southern Africa, ground recording stations are limited and the use of satellite data is needed for the studies where high spatial resolution data is required. We show the fast time variation of the geomagnetic field in the southern Africa region by deriving an harmonic spline model from CHAMP satellite measurements recorded between 2001 and 2010. The derived core field model, the Southern Africa Regional Model (SARM), is compared with the global model GRIMM-2 and the ground based data recorded at Hermanus magnetic observatory (HER) in South Africa and Tsumeb magnetic observatory (TSU) in Namibia where the focus is mainly on the long term variation of the geomagnetic field. The results of this study suggest that the regional model derived from the satellite data alone can be used to study the small scale features of the time variation of the geomagnetic field where ground data is not available. In addition, these results also support the earlier findings of the occurrence of a 2007 magnetic jerk and rapid secular variation fluctuations of 2003 and 2004 in the region.

  17. Age and origin of cold climate landforms from the Eastern Cape Drakensberg, southern Africa: palaeoclimatic implications

    NASA Astrophysics Data System (ADS)

    Mills, Stephanie C.; Barrows, Timothy T.; Fifield, L. Keith

    2014-05-01

    Reliable dating is crucial for resolving the nature and timing of cold events in southern Africa and the associated cold climate landforms produced. Evidence for glaciation has been proposed for the Eastern Cape Drakensberg, based on the identification of moraines that were presumed to be of last glacial maximum age. Temperature depressions of 10-17°C have been proposed for this region, based on the presence of these moraines (Lewis and Illgner, 2001) and the identification of a relict rock glacier. Such large temperature depressions are, however, unsupported by other palaeoclimatic proxies in southern Africa. Debate regarding the occurrence of glaciation in southern Africa has been ongoing for several decades. There is good evidence for small-scale glaciation during the last glacial cycle in Lesotho, at elevations exceeding 3000 m a.s.l., but these sites are more than 1000 m higher in elevation than those identified in the Eastern Cape, and suggest a temperature depression of only ~6°C and a change to a winter dominated precipitation regime during the last glacial cycle. This paper presents preliminary cosmogenic nuclide exposure ages for the Eastern Cape 'moraines' and a periglacial blockstream in this region. We discuss potential alternative interpretations for the formation of the landforms and suggest that glaciers were absent in the Eastern Cape Drakensberg during the last glacial period. However, there is widespread evidence for periglacial activity down to an elevation of ~1700 m a.s.l., as illustrated by extensive blockstreams, stone garlands and solifluction deposits. These periglacial deposits suggest that the climate was much colder (~6ºC) during the last glacial cycle, in keeping with other proxy records, but not cold enough to initiate or sustain glaciers at low elevations. References Lewis C. A., Illgner, P. M., 2001. Late Quaternary glaciation in Southern Africa: moraine ridges and glacial deposits at Mount Enterprise in the Drakensberg of the

  18. Crop response to climate change in southern Africa: A comprehensive review

    NASA Astrophysics Data System (ADS)

    Zinyengere, Nkulumo; Crespo, Olivier; Hachigonta, Sepo

    2013-12-01

    Concern over future food security in southern Africa has led to various studies that assess the impact of climate change on crops in the region. The results vary according to applied methods and tools. This study reviewed and consolidated results from 19 recent studies which quantitatively project the impact of climate change on crops for the 21st century in southern Africa. Results were assessed according to crop modelling techniques, which included process-based, statistical and economic (Ricardian) modelling. Studies were assessed for their reporting and recommendations concerning adaptation and CO2 fertilisation. Results suggest that the aggregate impact of climate change on crops in southern Africa will be negative. Maize yields are projected to decline on average by 18%. The collective impact of climate change on all crop yields shows a median decline of - 11% and - 14% respectively under process-based and statistical methodologies. Median impacts show declining crop yields through the 21st century. No significant change in the near future, - 18% for the mid century and - 30% for late century. GCM driven Ricardian projections are highly variable. However, uniform climate scenarios project a median revenue decline. Notwithstanding the challenges of such a review; lack of data, bias towards reported methods and tools, uncertainty, scale etc., results indicate that climate change may impact southern African crops in important ways thereby making adaptation essential. Adaptation and CO2 fertilisation could potentially moderate the negative impacts of climate change. This implies a need for studies into future adaptation that consider CO2 fertilisation.

  19. An assessment of renewable energy in Southern Africa: Wind, solar, hydro

    NASA Astrophysics Data System (ADS)

    Fant, Charles William, IV

    While electricity demand is rising quickly in the Southern African Power Pool (SAPP), the nations involved struggle to build the necessary infrastructure to meet the demand. In addition, the principal member---the Republic of South Africa---has made ambitious targets to reduce emissions via renewable energy technology. In this dissertation, three stand-alone studies on this subject are presented that address the future reliability of renewable energy in southern Africa, considering climate variability as well as long-term trends caused by climate change. In the first study, a suite of models are used to assess the vulnerability of the countries dependent on resources from the Zambezi River Basin to changes in climate. The study finds that the sectors most vulnerable to climate change are: hydropower in Zambia, irrigation in Zimbabwe and Mozambique, and flooding in Mozambique. In the second study, hourly reanalysis data is used to characterize wind power intermittency and assess the value of interconnection in southern Africa. The study finds that wind potential is high in Kenya, central Tanzania, and southern South Africa. With a closer look, wind power resource in South Africa is unreliable (i.e. intermittent) and is weak when power demand is highest on all relevant time-scales. In the third study, presented in Chapter 4, we develop a risk profile for changes in the long-term mean of wind and solar power sources. To do this, we use a statistical relationship between global mean temperature and each local gridded wind speed and solar radiation from the GCMs. We find that only small changes in wind speed and solar radiation are predicted in the median of the distributions projected to 2050. Furthermore, at the extremes of the distribution, relatively significant changes are predicted in some parts of southern Africa, and are associated with low probability. Finally, in the conclusion chapter, limitations and assumptions are listed for each of the three studies

  20. Evaluation of two GCMs in simulating rainfall inter-annual variability over Southern Africa

    NASA Astrophysics Data System (ADS)

    Klutse, Nana Ama Browne; Abiodun, Babatunde J.; Hewitson, Bruce C.; Gutowski, William J.; Tadross, Mark A.

    2016-02-01

    We evaluate the performance of two global circulation models (GCMs) over Southern Africa, as part of the efforts to improve the skill of seasonal forecast from a multi-model ensemble system over the region. The two GCMs evaluated in the study are the Community Atmosphere Model version 3 (CAM3) and the Hadley Centre Atmospheric Model version 3 (HadAM3). The study analyzed 30-year climate simulations from the models and compared the results with those from Climate Research Unit (CRU) and National Center for Environmental Prediction (NCEP) reanalysis dataset. The evaluation focused on how well the models simulate circulation features, seasonal variation of temperature and rainfall, and the inter-annual rainfall and circulations during El Niño Southern Oscillation (ENSO) years. The study also investigated the relationship between the regional rainfall from the models and global sea surface temperature (SST) during the El Niño and La Niña years. The results show that both GCMs simulate the circulation features and the seasonal cycles of rainfall and temperature fairly well. The location and magnitude of maxima and minima in surface temperature, sea level pressure (SLP), and rainfall fields are well reproduced. The maximum error in the simulated temperature fields is about 2 °, 4 mb in SLP and 8 mm/day in rainfall. However, CAM3 shows a major bias in simulating the summer rainfall; it simulates the maximum rainfall along the western part of Southern Africa, instead of the eastern part. The phase of the seasonal cycles is well reproduced, but the amplitude is underestimated over the Western Cape. Both CAM3 and HadAM3 give reasonable simulations of significant relationship between the regional rainfall and SST over the Nino 3.4 region and show that ENSO strongly drives the climate of Southern Africa. Hence, the model simulations could contribute to understanding the climate of the region and improve seasonal forecasts over Southern Africa.

  1. Epidemiologic and Environmental Risk Factors of Rift Valley Fever in Southern Africa from 2008 to 2011

    PubMed Central

    Glancey, Margaret M.; Linthicum, Kenneth J.

    2015-01-01

    Abstract Background: Rift Valley fever (RVF) outbreaks have been associated with periods of widespread and above-normal rainfall over several months. Knowledge on the environmental factors influencing disease transmission dynamics has provided the basis for developing models to predict RVF outbreaks in Africa. From 2008 to 2011, South Africa experienced the worst wave of RVF outbreaks in almost 40 years. We investigated rainfall-associated environmental factors in southern Africa preceding these outbreaks. Methods: RVF epizootic records obtained from the World Animal Health Information Database (WAHID), documenting livestock species affected, location, and time, were analyzed. Environmental variables including rainfall and satellite-derived normalized difference vegetation index (NDVI) data were collected and assessed in outbreak regions to understand the underlying drivers of the outbreaks. Results: The predominant domestic vertebrate species affected in 2008 and 2009 were cattle, when outbreaks were concentrated in the eastern provinces of South Africa. In 2010 and 2011, outbreaks occurred in the interior and southern provinces affecting over 16,000 sheep. The highest number of cases occurred between January and April but epidemics occurred in different regions every year, moving from the northeast of South Africa toward the southwest with each progressing year. The outbreaks showed a pattern of increased rainfall preceding epizootics ranging from 9 to 152 days; however, NDVI and rainfall were less correlated with the start of the outbreaks than has been observed in eastern Africa. Conclusions: Analyses of the multiyear RVF outbreaks of 2008 to 2011 in South Africa indicated that rainfall, NDVI, and other environmental and geographical factors, such as land use, drainage, and topography, play a role in disease emergence. Current and future investigations into these factors will be able to contribute to improving spatial accuracy of models to map risk areas

  2. Geological setting and age of Australopithecus sediba from southern Africa.

    PubMed

    Dirks, Paul H G M; Kibii, Job M; Kuhn, Brian F; Steininger, Christine; Churchill, Steven E; Kramers, Jan D; Pickering, Robyn; Farber, Daniel L; Mériaux, Anne-Sophie; Herries, Andy I R; King, Geoffrey C P; Berger, Lee R

    2010-04-01

    We describe the geological, geochronological, geomorphological, and faunal context of the Malapa site and the fossils of Australopithecus sediba. The hominins occur with a macrofauna assemblage that existed in Africa between 2.36 and 1.50 million years ago (Ma). The fossils are encased in water-laid, clastic sediments that were deposited along the lower parts of what is now a deeply eroded cave system, immediately above a flowstone layer with a U-Pb date of 2.026 +/- 0.021 Ma. The flowstone has a reversed paleomagnetic signature and the overlying hominin-bearing sediments are of normal polarity, indicating deposition during the 1.95- to 1.78-Ma Olduvai Subchron. The two hominin specimens were buried together in a single debris flow that lithified soon after deposition in a phreatic environment inaccessible to scavengers. PMID:20378812

  3. Maternal mortality in Malawi, 1977–2012

    PubMed Central

    Colbourn, Tim; Lewycka, Sonia; Nambiar, Bejoy; Anwar, Iqbal; Phoya, Ann; Mhango, Chisale

    2013-01-01

    Background Millennium Development Goal 5 (MDG 5) targets a 75% reduction in maternal mortality from 1990 to 2015, yet accurate information on trends in maternal mortality and what drives them is sparse. We aimed to fill this gap for Malawi, a country in sub-Saharan Africa with high maternal mortality. Methods We reviewed the literature for population-based studies that provide estimates of the maternal mortality ratio (MMR) in Malawi, and for studies that list and justify variables potentially associated with trends in MMR. We used all population-based estimates of MMR representative of the whole of Malawi to construct a best-fit trend-line for the range of years with available data, calculated the proportion attributable to HIV and qualitatively analysed trends and evidence related to other covariates to logically assess likely candidate drivers of the observed trend in MMR. Results 14 suitable estimates of MMR were found, covering the years 1977–2010. The resulting best-fit line predicted MMR in Malawi to have increased from 317 maternal deaths/100 000 live-births in 1980 to 748 in 1990, before peaking at 971 in 1999, and falling to 846 in 2005 and 484 in 2010. Concurrent deteriorations and improvements in HIV and health system investment and provisions are the most plausible explanations for the trend. Female literacy and education, family planning and poverty reduction could play more of a role if thresholds are passed in the coming years. Conclusions The decrease in MMR in Malawi is encouraging as it appears that recent efforts to control HIV and improve the health system are bearing fruit. Sustained efforts to prevent and treat maternal complications are required if Malawi is to attain the MDG 5 target and save the lives of more of its mothers in years to come. PMID:24353257

  4. Political challenges to implementing IWRM in Southern Africa

    NASA Astrophysics Data System (ADS)

    Swatuk, Larry A.

    Southern African states are undertaking comprehensive water sector reforms. While motives for reform are partially local, they are in large part driven by the interests and ideologies of Western states and civil societies. Within the Southern African Development Community (SADC), national (water, sanitation, irrigation) master plans are being written or revised. In several states, new Water Acts are in place and new institutions have been created to improve delivery. The stated goal of these activities is integrated water resources management (IWRM) defined simply as equitable, efficient and sustainable use of the resource. This article summarizes findings of social science-oriented scholarship on water management in the region, in particular that published in three special issues of Physics and Chemistry of the Earth (vol. 27, nos. 11-22; vol. 28, nos. 20-27; vol. 29, nos. 15-18). Evidence shows, among other things, that governments have been reluctant to devolve power to stakeholders; that rural dwellers are suspicious of the motives behind reform; that already empowered actors dominate new institutions touting broad-based participation; that efforts to fully recover costs in urban areas have been met with widespread civil resistance; and that new institutions have undermined existing forms of cooperation and conflict resolution, making matters worse not better. At the same time, these studies show the utility of decision support tools, capacity building exercises and research and knowledge production-all positive outcomes that should not be discounted. The paper argues that difficulties with reform reflect the highly political nature of the undertaking. Specifically, the new water architecture proposes a profound realignment of decision making power in already fragile, underdeveloped states. As a result, what may have started as a project now constitutes a context wherein differently empowered actors negotiate and renegotiate roles and rights to resources. Thus

  5. Mantle P wave travel time tomography of Eastern and Southern Africa: New images of mantle upwellings

    NASA Astrophysics Data System (ADS)

    Benoit, M. H.; Li, C.; van der Hilst, R.

    2006-12-01

    Much of Eastern Africa, including Ethiopia, Kenya, and Tanzania, has undergone extensive tectonism, including rifting, uplift, and volcanism during the Cenozoic. The cause of this tectonism is often attributed to the presence of one or more mantle upwellings, including starting thermal plumes and superplumes. Previous regional seismic studies and global tomographic models show conflicting results regarding the spatial and thermal characteristics of these upwellings. Additionally, there are questions concerning the extent to which the Archean and Proterozoic lithosphere has been altered by possible thermal upwellings in the mantle. To further constrain the mantle structure beneath Southern and Eastern Africa and to investigate the origin of the tectonism in Eastern Africa, we present preliminary results of a large-scale P wave travel time tomographic study of the region. We invert travel time measurements from the EHB database with travel time measurements taken from regional PASSCAL datasets including the Ethiopia Broadband Seismic Experiment (2000-2002); Kenya Broadband Seismic Experiment (2000-2002); Southern Africa Seismic Experiment (1997- 1999); Tanzania Broadband Seismic Experiment (1995-1997), and the Saudi Arabia PASSCAL Experiment (1995-1997). The tomographic inversion uses 3-D sensitivity kernels to combine different datasets and is parameterized with an irregular grid so that high spatial resolution can be obtained in areas of dense data coverage. It uses an adaptive least-squares context using the LSQR method with norm and gradient damping.

  6. Amietia angolensis and A. fuscigula (Anura: Pyxicephalidae) in southern Africa: a cold case reheated.

    PubMed

    Channing, Alan; Baptista, Ninda

    2013-01-01

    A study combining DNA sequences of the mitochondrial 16S rRNA gene, advertisement calls and morphology of some southern African river frogs confirms Amietia vandijki (Visser & Channing, 1997) as a good species. The form presently referred to as Amietia angolensis in southern Africa is shown to comprise two species: Amietia angolensis (Bocage, 1866) known from Angola, and Amietia quecketti (Boulenger, 1895) known from South Africa, Zimbabwe and Lesotho. Junior synonyms of A. quecketti include Rana theileri Mocquard, 1906 and Afrana dracomontana Channing, 1978. The form presently known as Amietia fuscigula is shown to consist of two distantly related taxa: Amietia fuscigula (Duméril & Bibron, 1841) from the south-western Cape and an undescribed species that we here name Amietia poyntoni sp. nov. Channing & Baptista, known from the rest of South Africa and Namibia. These five species have large differences in 16S sequences, as well as differences in morphology and advertisement call. Call and molecular data are both diagnostic, while morphology shows some overlap between taxa. An extended study of the genus across Africa is in preparation. PMID:26000433

  7. The Impact of International Teacher Migration on Schooling in Developing Countries--The Case of Southern Africa

    ERIC Educational Resources Information Center

    Appleton, Simon; Sives, Amanda; Morgan, W. John

    2006-01-01

    Whilst the migration of teachers has been a phenomenon for hundreds of years, the advent of "globalisation" has seen such migration return to prominence. This article focuses on the experiences of two developing countries in Southern Africa which have been on different ends of the process: South Africa as a net sender of teachers and Botswana as a…

  8. Mantle discontinuities under southern Africa from precursors to P′ P′df

    USGS Publications Warehouse

    Xu, Fei; Vidale, John E.; Earle, Paul; Benz, Harley M.

    1998-01-01

    We investigate the reflection properties of upper-mantle discontinuities beneath southern Africa using precursors to the df branch of PKPPKP (P′ P′). The P′ P′df branch is weaker than the ab and bc branches, but it does not have the complication of a caustic and appears across a wider distance range. Stacks from hundreds of short-period seismograms recorded in California from the March 9, 1994 Tonga earthquake (Mw = 7.6) show an ∼5% reflection (at 3.5 s dominate period) from 660-km depth indicating a sharp “660” under southern Africa. A 3.5 s period reflection from 410-km depth is also visible in these stacks, but only ∼2% the strength of P′ P′df. This result contrasts with the observation of the “410” and the “660” reflecting comparable amounts of high-frequency energy under the Indian Ocean [Benz and Vidale, 1993a], indicating either a diffuse “410” boundary under southern Africa or global variations in the impedance change across the “410”. A 1.5 s period reflection may indicate the existence of fine-scale heterogeneity near 320-km depth. Reflectivity synthetic seismograms also show that a previously claimed reflection from 785-km depth has the more likely explanation as PcPPKP.

  9. Mantle discontinuities under southern Africa from precursors to P‧ P‧df

    NASA Astrophysics Data System (ADS)

    Xu, Fei; Vidale, John E.; Earle, Paul S.; Benz, Harley M.

    We investigate the reflection properties of upper-mantle discontinuities beneath southern Africa using precursors to the df branch of PKPPKP (P‧ P‧). The P‧ P‧ df branch is weaker than the ab and bc branches, but it does not have the complication of a caustic and appears across a wider distance range. Stacks from hundreds of short-period seismograms recorded in California from the March 9, 1994 Tonga earthquake (Mw = 7.6) show an ∼5% reflection (at 3.5 s dominate period) from 660-km depth indicating a sharp “660” under southern Africa. A 3.5 s period reflection from 410-km depth is also visible in these stacks, but only ∼2% the strength of P‧ P‧df. This result contrasts with the observation of the “410” and the “660” reflecting comparable amounts of high-frequency energy under the Indian Ocean [Benz and Vidale, 1993a], indicating either a diffuse “410” boundary under southern Africa or global variations in the impedance change across the “410”. A 1.5 s period reflection may indicate the existence of fine-scale heterogeneity near 320-km depth. Reflectivity synthetic seismograms also show that a previously claimed reflection from 785-km depth has the more likely explanation as PcPPKP.

  10. Macroeconomics, (Adult) Education, and Poverty Eradication in Southern Africa

    NASA Astrophysics Data System (ADS)

    Nhamo, Senia; Nhamo, Godwell

    2006-05-01

    The Millennium Summit held in New York in September 2000 outlined the Millennium Development Goals (MDGs). The first of these involves the eradication of extreme poverty and hunger, setting two targets: halving by 2015 the percentage of the world's populace in 1990 with income less than US-1 a day (i.e., cutting this percentage from 27.9 to 14%); and halving the share of people who suffer from hunger. As for education, the MDGs seek to ensure that all children can complete primary schooling by 2015. Drawing on examples from selected southern African countries, the present study examines the need to strengthen economic support for (adult) education as an instrument of poverty eradication. It argues that human capital is one of the fundamental determinants of economic growth, and that this economic resource is essentially determined in both qualitative and quantitative regards by education.

  11. Investigating the Influence of Pre-Existing Basement Structures on the Propagation of the Malawi Rift using SRTM, RADARSAT, and Aeromagnetic Data

    NASA Astrophysics Data System (ADS)

    Robertson, K.; Atekwana, E. A.; Abdelsalam, M. G.; Laó-Dávila, D. A.

    2015-12-01

    The Malawi rift is a Neogene, amagmatic rift located where the Western Branch of the East Africa Rift System (EARS) terminates. In more mature rifts, magmatism is frequently recognized as a driving factor in rift propagation; however, the amagmatic nature of the Malawi rift permits investigation into the relationship between pre-existing structures and current rift propagation, without the influence of magmatism. To map surface structures, we used Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) and RADARSAT imagery over southern Malawi. To process the SRTM data, we applied edge enhancing filters and derivatives, and extracted topographic profiles to examine scarp height and minimum vertical exposed displacement. We mapped morphologically-defined structures by filtering the RADARSAT imagery using an enhanced lee filter to reduce noise and a Laplacian filter for edge enhancement. To examine Precambrian basement structures, we filtered aeromagnetic data using vertical and horizontal derivatives, tilt derivative, and analytic signal to create magnetic anomaly maps. Surface mapping indicated three primary trends in the southern Malawi rift: NW-SE (dominant), NE-SW, both of which are most likely the remnants of Mesozoic Karoo rifting, and a NNE-SSW trend seen in Neogene rifting. The Precambrian basement structural mapping also reveals three primary trends: WNW-ESE, NE-SW, and NW-SE. Ductile deformation causes the dominant basement fabric to change, switching polarity as the rift propagated southward from NE-SW orientation to NW-SE and WNW-ESE orientations, and back to a NE-SW orientation. In general, the surficial structures follow this trend. In some areas, however, the more recent rifting cut across pre-existing basement structures, possibly due to rheological heterogeneities or selective strain partitioning. Nonetheless, pre-existing basement structures played a critical role in strain localization and fault propagation in Malawi. However

  12. New insights into the history of the C-14010 lactase persistence variant in Eastern and Southern Africa.

    PubMed

    Macholdt, Enrico; Slatkin, Montgomery; Pakendorf, Brigitte; Stoneking, Mark

    2015-04-01

    Lactase persistence (LP), the ability to digest lactose into adulthood, is strongly associated with the cultural traits of pastoralism and milk-drinking among human populations, and several different genetic variants are known that confer LP. Recent studies of LP variants in Southern African populations, with a focus on Khoisan-speaking groups, found high frequencies of an LP variant (the C-14010 allele) that also occurs in Eastern Africa, and concluded that the C-14010 allele was brought to Southern Africa via a migration of pastoralists from Eastern Africa. However, this conclusion was based on indirect evidence; to date no study has jointly analyzed data on the C-14010 allele from both Southern African Khoisan-speaking groups and Eastern Africa. Here, we combine and analyze published data on the C-14010 allele in Southern and Eastern African populations, consisting of haplotypes with the C-14010 allele and four closely-linked short tandem repeat loci. Our results provide direct evidence for the previously-hypothesized Eastern African origin of the C-14010 allele in Southern African Khoisan-speaking groups. In addition, we find evidence for a separate introduction of the C-14010 allele into the Bantu-speaking Xhosa. The estimated selection intensity on the C-14010 allele in Eastern Africa is lower than that in Southern Africa, which suggests that in Eastern Africa the dietary changes conferring the fitness advantage associated with LP occurred some time after the origin of the C-14010 allele. Conversely, in Southern Africa the fitness advantage was present when the allele was introduced, as would be expected if pastoralism was introduced concomitantly. PMID:25448164

  13. Southern Mozambique basin: most promising hydrocarbon province offshore eat Africa

    SciTech Connect

    De Buyl, M.; Flores, G.

    1984-09-01

    Recent offshore acquisition of 12,800 km (8,000 mi) of seismic reflection data, with gravity and magnetic profiles encompassing the southern half of the Mozambique basin, reveals new facets of the subsurface geology. Integrated interpretation of these new geophysical data with old well information results in the development of depositional and tectonic models that positively establish the hydrocarbon potential of the basin. The recent comprehensive interpretation affords the following conclusions. (1) Significant oil shows accompany wet gas discoveries suggest that the South Mozambique basin is a mature province, as the hydrocarbon associations imply thermogenic processes. (2) Super-Karoo marine Jurassic sequences have been encountered in Nhamura-1 well onshore from the application of seismic stratigraphy and well correlation. (3) Steeply dipping reflectors truncated by the pre-Cretaceous unconformity testify to significant tectonic activity preceding the breakup of Gondwanaland. Hence, preconceived ideas about the depth of the economic basement and the absence of mature source rocks of pre-Cretaceous age should be revised. (4) Wildcats in the vicinity of ample structural closures have not been, in retrospect, optimally positioned nor drilled to sufficient depth to test the viability of prospects mapped along a major offshore extension of the East African rift system delineated by this new survey.

  14. SPACES Project ARS AfricaE – Adaptive Resilience of Southern African ecosystems

    NASA Astrophysics Data System (ADS)

    Falge, Eva; Brümmer, Christian; Schmullius, Christiane; Hüttich, Christian; Scholes, Robert John; Midgley, Guy; Hickler, Thomas; Scheiter, Simon; Twine, Wayne; Bradshaw, Karen; Lück, Wolfgang; Thiel-Clemen, Thomas; Lenfers, Ulfia; Mukelabai, Mukufute; Kutsch, Werner

    2015-04-01

    Nowadays, many semi-arid ecosystems are affected by at least two different kinds of disturbances: land use (change) and climate change. Based on this, it can be hypothesized that even very resilient ecosystems may not return to their initial state after disturbance, but will rather adapt to a new steady-state. We name this phenomenon "Adaptive Resilience of Ecosystems" and use it as base for the research concept of ARS AfricaE. This project wants to go beyond older approaches that only describe structural changes in savannas and their drivers. It employs functional aspects, such as the investigation of biogeochemical cycles, but also targets a deeper understanding of the functional consequences of ecosystem changes caused by multiple disturbances, and defines "degradation" as a sustained loss in the broad set of ecosystem services, i.e. a decrease in natural capital. To achieve this goal, the project will • create a network of research clusters (with natural and altered vegetation) along an aridity gradient in the Greater Karoo, Kruger National Park in South Africa, and Kataba Forest Reserve in Zambia • link biogeochemical functions with ecosystem structure, diversity of species and eco-physiological properties • describe ecosystem disturbance (and recovery) in terms of ecosystem function such as carbon balance components and water use efficiency • build an individual-based model to predict ecosystem dynamics under (post) disturbance managements • combine this model with long-term landscape dynamic information derived from remote sensing and aerial photography • develop sustainable management strategies for disturbed ecosystems and land use change

  15. Emissions of mercury in Southern Africa derived from long-term observations at Cape Point, South Africa

    NASA Astrophysics Data System (ADS)

    Brunke, E.-G.; Ebinghaus, R.; Kock, H. H.; Labuschagne, C.; Slemr, F.

    2012-05-01

    Mercury emissions in South Africa have so far been estimated only by a bottom-up approach from activities and emission factors for different processes. In this paper we derive GEM/CO (GEM being gaseous elemental mercury, Hg0), GEM/CO2, GEM/CH4, CO/CO2, CH4/CO2, and CH4/CO emission ratios from plumes observed during long-term monitoring of these species at Cape Point between March 2007 and December 2009. The average observed GEM/CO, GEM/CO2, GEM/CH4, CO/CO2, CH4/CO2, and CH4/CO emission ratios were 2.40 ± 2.65 pg m-3 ppb-1 (n = 47), 62.7 ± 80.2 pg m-3 ppb-1 (n = 44), 3.61 ± 4.66 pg m-3 ppb-1 (n = 46), 35.6 ± 25.4 ppb ppm-1 (n = 52), 20.2 ± 15.5 ppb ppm-1 (n=48), and 0.876 ± 1.106 ppb ppm-1 (n=42), respectively. The observed CO/CO2, CH4/CO2, and CH4/CO emission ratios agree within the combined uncertainties of the observations and emissions with the ratios calculated from EDGAR (version 4.2) CO2, CO, and CH4 inventories for South Africa and Southern Africa (South Africa, Lesotho, Swaziland, Namibia, Botswana, Zimbabwe, and Mozambique) in 2007 and 2008 (inventories for 2009 are not available yet). Total elemental mercury emission of 13.1, 15.2, and 16.1 t Hg yr-1 are estimated independently using the GEM/CO, GEM/CO2, and GEM/CH4 emission ratios and the annual mean CO, CO2, and CH4 emissions, respectively, of South Africa in 2007 and 2008. The average of these independent estimates of 14.8 ± 1.5 t GEM yr-1 is much less than the total emission of 257 t Hg yr-1 from older inventories. Considering that emission of GEM represents only 50-78% of all mercury emissions, our estimates come close to the total mercury emission estimates ranging between 40-50 t Hg yr-1 from more recent inventories.

  16. Rainfall variability over southern Africa: an overview of current research using satellite and climate model data

    NASA Astrophysics Data System (ADS)

    Williams, C.; Kniveton, D.; Layberry, R.

    2009-04-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. In this research, satellite-derived rainfall data are used as a basis for undertaking model experiments using a state-of-the-art climate model, run at both high and low spatial resolution. Once the model's ability to reproduce extremes has been assessed, idealised regions of sea surface temperature (SST) anomalies are used to force the model, with the overall aim of investigating the ways in which SST anomalies influence rainfall extremes over southern Africa. In this paper, a brief overview is given of the authors' research to date, pertaining to southern African rainfall. This covers (i) a description of present-day rainfall variability over southern Africa; (ii) a comparison of model simulated daily rainfall with the satellite-derived dataset; (iii) results from sensitivity testing of the model's domain size; and (iv) results from the idealised SST experiments.

  17. Emissions of Trace Gases and Particles from Savanna Fires in Southern Africa

    NASA Technical Reports Server (NTRS)

    Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Bertschi, Isaac T.; Blake, Donald R.; Simpson, Isobel J.; Gao, Song; Kirchstetter, Thomas W.; Novakov, Tica

    2003-01-01

    Airborne measurements made on initial smoke from 10 savanna fires in southern Africa provide quantitative data on emissions of 50 gaseous and particulate species, including carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, methane, ammonia, dimethyl sulfide, nonmethane organic compounds, halocarbons, gaseous organic acids, aerosol ionic components, carbonaceous aerosols, and condensation nuclei (CN). Measurements of several of the gaseous species by gas chromatography and Fourier transform infrared spectroscopy are compared. Emission ratios and emission factors are given for eight species that have not been reported previously for biomass burning of savanna in southern Africa (namely, dimethyl sulfide, methyl nitrate, five hydrocarbons, and particles with diameters from 0.1 to 3 microns). The emission factor that we measured for ammonia is lower by a factor of 4, and the emission factors for formaldehyde, hydrogen cyanide, and CN are greater by factors of about 3, 20, and 3 - 15, respectively, than previously reported values. The new emission factors are used to estimate annual emissions of these species from savanna fires in Africa and worldwide.

  18. Cultural Diffusion Was the Main Driving Mechanism of the Neolithic Transition in Southern Africa

    PubMed Central

    Jerardino, Antonieta; Fort, Joaquim; Isern, Neus; Rondelli, Bernardo

    2014-01-01

    It is well known that the Neolithic transition spread across Europe at a speed of about 1 km/yr. This result has been previously interpreted as a range expansion of the Neolithic driven mainly by demic diffusion (whereas cultural diffusion played a secondary role). However, a long-standing problem is whether this value (1 km/yr) and its interpretation (mainly demic diffusion) are characteristic only of Europe or universal (i.e. intrinsic features of Neolithic transitions all over the world). So far Neolithic spread rates outside Europe have been barely measured, and Neolithic spread rates substantially faster than 1 km/yr have not been previously reported. Here we show that the transition from hunting and gathering into herding in southern Africa spread at a rate of about 2.4 km/yr, i.e. about twice faster than the European Neolithic transition. Thus the value 1 km/yr is not a universal feature of Neolithic transitions in the world. Resorting to a recent demic-cultural wave-of-advance model, we also find that the main mechanism at work in the southern African Neolithic spread was cultural diffusion (whereas demic diffusion played a secondary role). This is in sharp contrast to the European Neolithic. Our results further suggest that Neolithic spread rates could be mainly driven by cultural diffusion in cases where the final state of this transition is herding/pastoralism (such as in southern Africa) rather than farming and stockbreeding (as in Europe). PMID:25517968

  19. Fine-Scale Human Population Structure in Southern Africa Reflects Ecogeographic Boundaries.

    PubMed

    Uren, Caitlin; Kim, Minju; Martin, Alicia R; Bobo, Dean; Gignoux, Christopher R; van Helden, Paul D; Möller, Marlo; Hoal, Eileen G; Henn, Brenna M

    2016-09-01

    Recent genetic studies have established that the KhoeSan populations of southern Africa are distinct from all other African populations and have remained largely isolated during human prehistory until ∼2000 years ago. Dozens of different KhoeSan groups exist, belonging to three different language families, but very little is known about their population history. We examine new genome-wide polymorphism data and whole mitochondrial genomes for >100 South Africans from the ≠Khomani San and Nama populations of the Northern Cape, analyzed in conjunction with 19 additional southern African populations. Our analyses reveal fine-scale population structure in and around the Kalahari Desert. Surprisingly, this structure does not always correspond to linguistic or subsistence categories as previously suggested, but rather reflects the role of geographic barriers and the ecology of the greater Kalahari Basin. Regardless of subsistence strategy, the indigenous Khoe-speaking Nama pastoralists and the N|u-speaking ≠Khomani (formerly hunter-gatherers) share ancestry with other Khoe-speaking forager populations that form a rim around the Kalahari Desert. We reconstruct earlier migration patterns and estimate that the southern Kalahari populations were among the last to experience gene flow from Bantu speakers, ∼14 generations ago. We conclude that local adoption of pastoralism, at least by the Nama, appears to have been primarily a cultural process with limited genetic impact from eastern Africa. PMID:27474727

  20. Biology and genetics of oculocutaneous albinism and vitiligo - common pigmentation disorders in southern Africa.

    PubMed

    Manga, Prashiela; Kerr, Robyn; Ramsay, Michèle; Kromberg, Jennifer G R

    2013-12-01

    Pigmentation disorders span the genetic spectrum from single-gene autosomal recessive disorders such as oculocutaneous albinism (OCA), the autosomal dominant disorder piebaldism to X-linked ocular albinism and multifactorial vitiligo. OCA connotes a group of disorders that result in hypopigmented skin due to decreased melanin production in melanocytes and loss of visual acuity. There are four non-syndromic forms, OCA1-4, which are classified based on the gene that is mutated (tyrosinase, OCA2, tyrosinase-related protein 1 and SLC45A2, respectively). Despite the fact that multiple genes account for the various forms of OCA, the phenotypes of all four forms result from disruption in the maturation and trafficking of the enzyme tyrosinase. OCA2 is the most prevalent autosomal recessive disorder among southern African blacks, affecting 1/3 900 individuals; while OCA3, although rare, is most prevalent in southern Africa. Another common pigmentation disorder in southern Africa is vitiligo, which affects 1 - 2% of people worldwide. Vitiligo is a complex, acquired disorder in which melanocytes are destroyed due to an autoimmune response. The aetiology underlying this disorder is poorly understood, although recent genetic association studies have begun to shed light on the contributing factors. Pigmentation disorders have significant psychosocial implications and co-morbidities, yet therapies are still lacking. Recent progress in our understanding of the pathobiology of both albinism and vitiligo may herald novel treatment strategies for these disorders.  PMID:24300644

  1. Agricultural nematology in East and Southern Africa: problems, management strategies and stakeholder linkages.

    PubMed

    Talwana, Herbert; Sibanda, Zibusiso; Wanjohi, Waceke; Kimenju, Wangai; Luambano-Nyoni, Nessie; Massawe, Cornel; Manzanilla-López, Rosa H; Davies, Keith G; Hunt, David J; Sikora, Richard A; Coyne, Danny L; Gowen, Simon R; Kerry, Brian R

    2016-02-01

    By 2050, Africa's population is projected to exceed 2 billion. Africa will have to increase food production more than 50% in the coming 50 years to meet the nutritional requirements of its growing population. Nowhere is the need to increase agricultural productivity more pertinent than in much of Sub-Saharan Africa, where it is currently static or declining. Optimal pest management will be essential, because intensification of any system creates heightened selection pressures for pests. Plant-parasitic nematodes and their damage potential are intertwined with intensified systems and can be an indicator of unsustainable practices. As soil pests, nematodes are commonly overlooked or misdiagnosed, particularly where appropriate expertise and knowledge transfer systems are meager or inadequately funded. Nematode damage to roots results in less efficient root systems that are less able to access nutrients and water, which can produce symptoms typical of water or nutrient deficiency, leading to misdiagnosis of the underlying cause. Damage in subsistence agriculture is exacerbated by growing crops on degraded soils and in areas of low water retention where strong root growth is vital. This review focuses on the current knowledge of economically important nematode pests affecting key crops, nematode control methods and the research and development needs for sustainable management, stakeholder involvement and capacity building in the context of crop security in East and Southern Africa, especially Kenya, Tanzania, Uganda and Zimbabwe. PMID:26299755

  2. Oil and gas developments in central and southern Africa in 1985

    SciTech Connect

    Petracca, A.N.

    1986-10-01

    Oil industry activity in central and southern Africa appears to have stabilized in the last few years, but some activities (such as field development and exploration acreage acquisition) are still declining. Several countries have advertised open concessions and invited bids. Only in a very few cases have the offers stimulated the interest of oil companies. An exceptional increase in exploration concession acquisition took place in the East Africa rift area. Land seismic acquisition increased mostly in Nigeria, but 1985 marine seismic activity was half the 1984 activity. Exploration drilling was higher than in 1984, but development drilling was considerably lower. Significant discoveries were made in Gabon and Angola. Production increased 8%, with the largest and most significant increase in Angola, followed by Gabon. The production share of non-OPEC versus OPEC countries remained stable at 33%. 33 figures, 6 tables.

  3. Choir singing in Subsaharan Africa: Acoustic factors of a regional style in southern Mozambique

    NASA Astrophysics Data System (ADS)

    Soeiro de Carvalho, Joao

    2005-09-01

    Choir singing is a most prominent form of expressive behavior in Subsaharan Africa. A vast majority of expressive modes involves multipart singing, both within the framework of European tonal system as well as other structured ways of combining vocal sounds of different frequencies. Vocal improvisation stands as an important process for the course of performance; individual voice ranges, as well as issues of social status and musical competence, determine the ways musicians participate in performance. Aesthetic validation is often expressed by the use of a nonverbal expressive mode, ``kulungwani,'' a vocal technique involving the action of the lower maxillae and tongue in order to produce a low-frequency interruption of sound emission. Choral singing intonation processes seem to rely on harmonic results, rather than melodic. A regional choral style in southern Africa seems to have developed, where a particular distribution of formant frequencies and an emphasis on low-frequency energy play a significant role.

  4. Variability of the propagation coefficients due to rain for microwave links in southern Africa

    NASA Astrophysics Data System (ADS)

    Mulangu, C. T.; Afullo, T. J.

    2009-06-01

    We use the Mie scattering approach and the dielectric model of Liebe to determine the propagation coefficients and rain attenuation distribution for four locations in Botswana, southern Africa, using R0.01 = 68.9 mm/h for Gaborone, R0.01 = 137.06 mm/h for Selebi-Phikwe, R0.01 = 86.87 mm/h for Francistown, and R0.01 = 64.4 mm/h for Kasane over the frequency range of 1-1000 GHz. The results show that the extinction coefficients depend more strongly on temperature at lower frequencies than at higher frequencies for lognormal distribution. The absorption coefficient is significant but decreases exponentially with rain temperature at lower microwave frequencies. The application of the proposed model with various distributions is corroborated using practical results for Durban in South Africa.

  5. First Ground-based Observation of Transient Luminous Events over Southern Africa

    NASA Astrophysics Data System (ADS)

    Nnadih, Ogechukwu; Kosch, Michael; Martinez, Peter

    2016-07-01

    We present the first ground-based observations in southern Africa of Transient Luminous Events (TLEs) in the summer of 2015/16 over convective thunderstorms. For the months of December to February, South Africa has one of the highest lightning stroke rates in the world. This was part of the AfriSprite campaign initiated by the South African National Space Agency. These observations show a variety of fine structures such as tree-like shaped, carrot, angel and jellyfish-shaped sprites. The South African Weather Service array of VLF receivers is used to locate and quantify the magnitude and polarity of the lightning strikes associated with TLEs. We plan to make bi-static as well as multi-wavelength observations in future.

  6. Geostatistical modelling of household malaria in Malawi

    NASA Astrophysics Data System (ADS)

    Chirombo, J.; Lowe, R.; Kazembe, L.

    2012-04-01

    Malaria is one of the most important diseases in the world today, common in tropical and subtropical areas with sub-Saharan Africa being the region most burdened, including Malawi. This region has the right combination of biotic and abiotic components, including socioeconomic, climatic and environmental factors that sustain transmission of the disease. Differences in these conditions across the country consequently lead to spatial variation in risk of the disease. Analysis of nationwide survey data that takes into account this spatial variation is crucial in a resource constrained country like Malawi for targeted allocation of scare resources in the fight against malaria. Previous efforts to map malaria risk in Malawi have been based on limited data collected from small surveys. The Malaria Indicator Survey conducted in 2010 is the most comprehensive malaria survey carried out in Malawi and provides point referenced data for the study. The data has been shown to be spatially correlated. We use Bayesian logistic regression models with spatial correlation to model the relationship between malaria presence in children and covariates such as socioeconomic status of households and meteorological conditions. This spatial model is then used to assess how malaria varies spatially and a malaria risk map for Malawi is produced. By taking intervention measures into account, the developed model is used to assess whether they have an effect on the spatial distribution of the disease and Bayesian kriging is used to predict areas where malaria risk is more likely to increase. It is hoped that this study can help reveal areas that require more attention from the authorities in the continuing fight against malaria, particularly in children under the age of five.

  7. Central southern Africa at the time of the African Humid Period: A new analysis of Holocene palaeoenvironmental and palaeoclimate data.

    NASA Astrophysics Data System (ADS)

    Burrough, Sallie; Thomas, David

    2014-05-01

    The Holocene African Humid Period (c 14.8-5.5 ka) is now recognised in high-resolution records from western Africa as well as in tropical Africa north of the equator. Establishing a clear picture of Holocene environmental changes from palaeodata in central southern Africa is, however, proving both difficult and contentious. This is because in dryland systems in particular it can be difficult to distinguish the effects of sub-millennial scale regional climatic variability from those of major externally-forced global climate changes. We analyse and review existing records for central southern Africa, and neighbouring areas affected by the same climate systems, to attempt to build a clearer spatial picture of regional hydrological system responses during the Holocene. We suggest palaeodata, including new data from Makgadikgadi basin barchan dunes indicate mid-late Holocene aridity following a period of marked hydrological dynamism extending from the early Holocene. We propose that present-day conditions in central southern Africa are relatively stable compared to the early and mid-Holocene and infer that this period of relative stability in the landscape has occurred since ca. 2 ka. We explain Holocene hydrological changes through analysis of changing zonal climatic influences linked to Congo Air Boundary (CAB) and Intertropical Convergence Zone (ITCZ) dynamics, the effects of which filter into the region via complex drainage basin dynamics. It is proposed that, sensu stricto, the AHP was not a spatially uniform feature of early Holocene central southern Africa.

  8. Modelling Bambara Groundnut Yield in Southern Africa: Towards a Climate-Resilient Future

    NASA Technical Reports Server (NTRS)

    Karunaratne, A. S.; Walker, S.; Ruane, A. C.

    2015-01-01

    Current agriculture depends on a few major species grown as monocultures that are supported by global research underpinning current productivity. However, many hundreds of alternative crops have the potential to meet real world challenges by sustaining humanity, diversifying agricultural systems for food and nutritional security, and especially responding to climate change through their resilience to certain climate conditions. Bambara groundnut (Vigna subterranea (L.) Verdc.), an underutilised African legume, is an exemplar crop for climate resilience. Predicted yield performances of Bambara groundnut by AquaCrop (a crop-water productivity model) were evaluated for baseline (1980-2009) and mid-century climates (2040-2069) under 20 downscaled Global Climate Models (CMIP5-RCP8.5), as well as for climate sensitivities (AgMIPC3MP) across 3 locations in Southern Africa (Botswana, South Africa, Namibia). Different land - races of Bambara groundnut originating from various semi-arid African locations showed diverse yield performances with diverse sensitivities to climate. S19 originating from hot-dry conditions in Namibia has greater future yield potential compared to the Swaziland landrace Uniswa Red-UN across study sites. South Africa has the lowest yield under the current climate, indicating positive future yield trends. Namibia reported the highest baseline yield at optimum current temperatures, indicating less yield potential in future climates. Bambara groundnut shows positive yield potential at temperatures of up to 31degC, with further warming pushing yields down. Thus, many regions in Southern Africa can utilize Bambara groundnut successfully in the coming decades. This modelling exercise supports decisions on genotypic suitability for present and future climates at specific locations.

  9. Outcomes of infants starting antiretroviral therapy in Southern Africa, 2004-2012

    PubMed Central

    Porter, Mireille; Davies, Mary-Ann; Mapani, Muntanga K.; Rabie, Helena; Phiri, Sam; Nuttall, James; Fairlie, Lee; Technau, Karl-Günter; Stinson, Kathryn; Wood, Robin; Wellington, Maureen; Haas, Andreas D.; Giddy, Janet; Tanser, Frank; Eley, Brian

    2015-01-01

    Background There is limited published data on the outcomes of infants starting antiretroviral therapy (ART) in routine care in Southern Africa. This study aimed to examine the baseline characteristics and outcomes of infants initiating ART. Methods We analysed prospectively collected cohort data from routine ART initiation in infants from 11 cohorts contributing to the International Epidemiologic Database to Evaluate AIDS in Southern Africa. We included ART naïve HIV-infected infants <12 months of age initiating ≥ three antiretroviral drugs between 2004 and 2012. Kaplan-Meier estimates were calculated for mortality, loss to follow-up (LTFU), transfer out and virological suppression. We used Cox Proportional Hazards models stratified by cohort to determine baseline characteristics associated with outcomes mortality and virological suppression. Results The median (interquartile range) age at ART initiation of 4945 infants was 5.9 months (3.7-8.7) with follow-up of 11.2 months (2.8-20.0). At ART initiation 77% had WHO clinical stage 3 or 4 disease and 87% were severely immunosuppressed. Three-year mortality probability was 16% and LTFU 29%. Severe immunosuppression, WHO stage 3 or 4, anaemia, being severely underweight and initiation of treatment before 2010 were associated with higher mortality. At 12 months after ART initiation 17% of infants were severely immunosuppressed and the probability of attaining virological suppression was 56%. Conclusion Most infants initiating ART in Southern Africa had severe disease with high probability of LTFU and mortality on ART. Although the majority of infants remaining in care showed immune recovery and virological suppression, these responses were suboptimal. PMID:26167620

  10. Rainfall variability and extremes over southern Africa: assessment of a climate model to reproduce daily extremes

    NASA Astrophysics Data System (ADS)

    Williams, C.; Kniveton, D.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  11. Extreme Rainfall Events Over Southern Africa: Assessment of a Climate Model to Reproduce Daily Extremes

    NASA Astrophysics Data System (ADS)

    Williams, C.; Kniveton, D.; Layberry, R.

    2007-12-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable extreme events, due to a number of factors including extensive poverty, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of a state-of-the-art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. Once the model's ability to reproduce extremes has been assessed, idealised regions of SST anomalies are used to force the model, with the overall aim of investigating the ways in which SST anomalies influence rainfall extremes over southern Africa. In this paper, results from sensitivity testing of the UK Meteorological Office Hadley Centre's climate model's domain size are firstly presented. Then simulations of current climate from the model, operating in both regional and global mode, are compared to the MIRA dataset at daily timescales. Thirdly, the ability of the model to reproduce daily rainfall extremes will be assessed, again by a comparison with extremes from the MIRA dataset. Finally, the results from the idealised SST experiments are briefly presented, suggesting associations between rainfall extremes and both local and remote SST anomalies.

  12. Managing conflicts arising from fisheries enhancements based on non-native fishes in southern Africa.

    PubMed

    Ellender, B R; Woodford, D J; Weyl, O L F; Cowx, I G

    2014-12-01

    Southern Africa has a long history of non-native fish introductions for the enhancement of recreational and commercial fisheries, due to a perceived lack of suitable native species. This has resulted in some important inland fisheries being based on non-native fishes. Regionally, these introductions are predominantly not benign, and non-native fishes are considered one of the main threats to aquatic biodiversity because they affect native biota through predation, competition, habitat alteration, disease transfer and hybridization. To achieve national policy objectives of economic development, food security and poverty eradication, countries are increasingly looking towards inland fisheries as vehicles for development. As a result, conflicts have developed between economic and conservation objectives. In South Africa, as is the case for other invasive biota, the control and management of non-native fishes is included in the National Environmental Management: Biodiversity Act. Implementation measures include import and movement controls and, more recently, non-native fish eradication in conservation priority areas. Management actions are, however, complicated because many non-native fishes are important components in recreational and subsistence fisheries that contribute towards regional economies and food security. In other southern African countries, little attention has focussed on issues and management of non-native fishes, and this is cause for concern. This paper provides an overview of introductions, impacts and fisheries in southern Africa with emphasis on existing and evolving legislation, conflicts, implementation strategies and the sometimes innovative approaches that have been used to prioritize conservation areas and manage non-native fishes. PMID:25256916

  13. Climate change and maize yield in southern Africa: what can farm management do?

    PubMed

    Rurinda, Jairos; van Wijk, Mark T; Mapfumo, Paul; Descheemaeker, Katrien; Supit, Iwan; Giller, Ken E

    2015-12-01

    There is concern that food insecurity will increase in southern Africa due to climate change. We quantified the response of maize yield to projected climate change and to three key management options - planting date, fertilizer use and cultivar choice - using the crop simulation model, agricultural production systems simulator (APSIM), at two contrasting sites in Zimbabwe. Three climate periods up to 2100 were selected to cover both near- and long-term climates. Future climate data under two radiative forcing scenarios were generated from five global circulation models. The temperature is projected to increase significantly in Zimbabwe by 2100 with no significant change in mean annual total rainfall. When planting before mid-December with a high fertilizer rate, the simulated average grain yield for all three maize cultivars declined by 13% for the periods 2010-2039 and 2040-2069 and by 20% for 2070-2099 compared with the baseline climate, under low radiative forcing. Larger declines in yield of up to 32% were predicted for 2070-2099 with high radiative forcing. Despite differences in annual rainfall, similar trends in yield changes were observed for the two sites studied, Hwedza and Makoni. The yield response to delay in planting was nonlinear. Fertilizer increased yield significantly under both baseline and future climates. The response of maize to mineral nitrogen decreased with progressing climate change, implying a decrease in the optimal fertilizer rate in the future. Our results suggest that in the near future, improved crop and soil fertility management will remain important for enhanced maize yield. Towards the end of the 21st century, however, none of the farm management options tested in the study can avoid large yield losses in southern Africa due to climate change. There is a need to transform the current cropping systems of southern Africa to offset the negative impacts of climate change. PMID:26251975

  14. An archeomagnetic record from southern Africa and its bearing on the history of the South Atlantic Anomaly

    NASA Astrophysics Data System (ADS)

    Tarduno, John; Cottrell, Rory; Huffman, Thomas; Watkeys, Michael; Grigsby, Miriam; Blackman, Eric

    2016-04-01

    The paucity of Southern Hemisphere archeomagnetic data limits the resolution of paleosecular variation models, while at the same time important changes in the modern and historical field, including the recent dipole decay, appear to originate in this region. We have recently presented the first archeomagnetic data from Iron Age sites of southern Africa (˜1000-1650 AD) (Tarduno et al., Nature Communications, 2015). Magnetic data show a sharp intensity drop at ˜1300 AD, at a rate comparable to modern field changes in the South Atlantic Anomaly (SAA), but to lower values. These changes motivated our conceptual model whereby the recurrence of low field values reflects magnetic flux expulsion from the core, promoted by the unusual core-mantle boundary composition and structure beneath southern Africa as defined by seismology (specifically the African Large Low Velocity Seismic Province, or LLVSP). Because the African LLVSP is a longstanding structure, we expect this region to be a steady site of flux expulsion, and perhaps the triggering site for reversals, on time scales of millions of years. Here we discuss our ongoing efforts to extend the archeomagnetic record from southern Africa back in time, and further develop the flux expulsion- African LLVSP hypothesis, through new sampling and paleomagnetic analyses of Iron Age burnt huts, grain bins and kraals from South Africa, Zimbabwe and Botswana. Our preliminary analyses define a loop in the archeomagnetic curve for southern Africa between ca. 400 and 1000 AD, absent in predictions from available paleosecular variation models, that might record another flux expulsion episode.

  15. Drought regimes in Southern Africa and how well GCMs simulate them

    NASA Astrophysics Data System (ADS)

    Ujeneza, Eva L.; Abiodun, Babatunde J.

    2014-09-01

    This paper presents the spatial and temporal structures of drought regimes in Southern Africa and evaluates the capability of ten global climate models (GCMs) in simulating the regimes. The study uses a multi-scaled standardized index (called standardized precipitation evapo-transpiration index, SPEI) in characterizing droughts over Southern Africa at 3- and 12-month scales. The spatial patterns of the drought regimes are identified using the rotated principal component analysis (PCA) on the SPEI, while the temporal characteristics of the drought regimes are studied using wavelet analysis. The relationship between each drought regime and global SSTs (and climate indices) is quantified using correlation analysis and wavelet coherence analysis. The study also quantifies the capability of the GCMs in simulating the drought regimes. The PCA results show four main drought regimes that jointly explain about 50 % SPEI variance over South Africa. The drought regimes (hereafter PF1, PF2, PF3 and PF4) centre over the south-western part of Southern Africa (i.e. South Africa, Botswana and Namibia common border), Zimbabwe, Tanzania, and Angola, respectively. PF1, PF2 and PF4 are strongly correlated with SST over the South Atlantic, Tropical Pacific and Indian Oceans, while PF3 is strongly correlated with the SST over the Tropical Pacific, Atlantic and Indian Oceans. The drought regimes (except PF4) have significant coherence with some atmospheric teleconnection, but the strength, duration, and phase of the coherence vary with time. All the GCMs simulate the drought regimes better at a 3-month scale than at a 12-month scale. At a 3-month scale, 70 % of the GCMs simulate all the drought regimes with a high correlation coefficient (r > 0.6), but at a 12-month scale only 60 % of the models simulate at least three of the drought regimes with a high correlation coefficient (r > 0.6). The results of this study have applications in using GCMs to study the underlying atmospheric

  16. Drought regimes in Southern Africa and how well GCMs simulate them

    NASA Astrophysics Data System (ADS)

    Ujeneza, Eva L.; Abiodun, Babatunde J.

    2015-03-01

    This paper presents the spatial and temporal structures of drought regimes in Southern Africa and evaluates the capability of ten global climate models (GCMs) in simulating the regimes. The study uses a multi-scaled standardized index (called standardized precipitation evapo-transpiration index, SPEI) in characterizing droughts over Southern Africa at 3- and 12-month scales. The spatial patterns of the drought regimes are identified using the rotated principal component analysis (PCA) on the SPEI, while the temporal characteristics of the drought regimes are studied using wavelet analysis. The relationship between each drought regime and global SSTs (and climate indices) is quantified using correlation analysis and wavelet coherence analysis. The study also quantifies the capability of the GCMs in simulating the drought regimes. The PCA results show four main drought regimes that jointly explain about 50 % SPEI variance over South Africa. The drought regimes (hereafter PF1, PF2, PF3 and PF4) centre over the south-western part of Southern Africa (i.e. South Africa, Botswana and Namibia common border), Zimbabwe, Tanzania, and Angola, respectively. PF1, PF2 and PF4 are strongly correlated with SST over the South Atlantic, Tropical Pacific and Indian Oceans, while PF3 is strongly correlated with the SST over the Tropical Pacific, Atlantic and Indian Oceans. The drought regimes (except PF4) have significant coherence with some atmospheric teleconnection, but the strength, duration, and phase of the coherence vary with time. All the GCMs simulate the drought regimes better at a 3-month scale than at a 12-month scale. At a 3-month scale, 70 % of the GCMs simulate all the drought regimes with a high correlation coefficient (r > 0.6), but at a 12-month scale only 60 % of the models simulate at least three of the drought regimes with a high correlation coefficient (r > 0.6). The results of this study have applications in using GCMs to study the underlying atmospheric

  17. Do not forget the boys – gender differences in children living in high HIV-affected communities in South Africa and Malawi in a longitudinal, community-based study

    PubMed Central

    Hensels, I. S.; Sherr, L.; Skeen, S.; Macedo, A.; Roberts, K. J.; Tomlinson, M.

    2016-01-01

    ABSTRACT Gender is an important factor in child development. Especially in sub-Saharan Africa, girls have often been shown to be less likely to access education compared to boys. The consequence of this has been that that programmes addressing child development are often aimed at girls in order to redress gender imbalances. This study examines the effect of gender on the development of children attending community-based organisations in high HIV-affected areas, and explores whether community-based organisation attendance was associated with any changes in gender differences over time. Baseline data from 989 children and 12–15 month follow from 854 (86% response rate) were used to examine gender differences in children from Malawi and South Africa. At baseline, where there were differences by gender, these tended to disadvantage boys. It was found that boys were significantly more often found to be subjected to violence. Boys showed worse performance at school and more behavioural problems than girls. These gender differences persisted from baseline to follow-up. At follow-up, boys self-reported significantly worse average quality of life than girls. Only harsh discipline differed by gender in progression over time: boys experienced a stronger reduction in harsh physical discipline than girls from baseline to follow-up. Since harsh discipline was associated with boys’ worse educational outcomes and behavioural problems, our data cautiously suggests that gender differences could be reduced over time. In conclusion, our data suggests that, perhaps due to the narrow equity approach focusing on provision for girls, boys may be overlooked. As a result, there are some specific experiences where boys are generally worse off. These differences have distinct ramifications for the educational and emotional development of boys. A broader equity approach to child development might be warranted to ensure that the needs of both girls and boys are considered, and that boys are

  18. Interpretation of Nimbus-7 37 GHz microwave brightness temperature data in semi-arid southern Africa

    NASA Technical Reports Server (NTRS)

    Prince, S. D.; Choudhury, B. J.

    1989-01-01

    Monthly 37 GHz microwave polarization difference temperatures (MPDT) derived from the Nimbus-7 scanning multichannel microwave radiometer (SMMR) for southern Africa from 1979 to 1985 are compared with rainfall and Advanced Very High Resolution Radiometer (AVHRR) normalized difference vegetation index (NDVI) data. MPDT rose sharply during a drought episode which occurred within the period included in the data. The rise was seen not only in the growing season, but also in the dry season MPDT when no actively photosynthetic, water-containing leaves are present. The results suggest that scattering of the emitted microwave radiation by dead and living vegetation is a more important factor than has previously been recognized.

  19. Socio-epidemiological Aspects of Respiratory Allergic Diseases in Southern Africa

    PubMed Central

    Taborda-Barata, Luís

    2012-01-01

    Abstract The prevalence of respiratory allergic diseases has been increasing in Southern Africa both in urban and in rural environments. Various factors may contribute toward this situation, namely, exposure to aeroallergens, such as grass pollens and house dust mites. However, other irritant environmental triggers, such as exposure to tobacco smoke and certain indoor and outdoor fumes, may also play a relevant part. Furthermore, certain parasitic and mycobacterial infections may act as allergic disease risk modifiers, although such an influence should be confirmed. Finally, certain cultural and socioeconomic factors may also influence accessibility to healthcare and adherence to treatment of these diseases. PMID:23268464

  20. Big Sugar in southern Africa: rural development and the perverted potential of sugar/ethanol exports.

    PubMed

    Richardson, Ben

    2010-01-01

    This paper asks how investment in large-scale sugar cane production has contributed, and will contribute, to rural development in southern Africa. Taking a case study of the South African company Illovo in Zambia, the argument is made that the potential for greater tax revenue, domestic competition, access to resources and wealth distribution from sugar/ethanol production have all been perverted and with relatively little payoff in wage labour opportunities in return. If the benefits of agro-exports cannot be so easily assumed, then the prospective 'balance sheet' of biofuels needs to be re-examined. In this light, the paper advocates smaller-scale agrarian initiatives. PMID:20873031

  1. Assessment of a climate model to reproduce rainfall variability and extremes over Southern Africa

    NASA Astrophysics Data System (ADS)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2010-01-01

    It is increasingly accepted that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The sub-continent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite-derived rainfall data from the Microwave Infrared Rainfall Algorithm (MIRA). This dataset covers the period from 1993 to 2002 and the whole of southern Africa at a spatial resolution of 0.1° longitude/latitude. This paper concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of present-day rainfall variability over southern Africa and is not intended to discuss possible future changes in climate as these have been documented elsewhere. Simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. Secondly, the ability of the model to reproduce daily rainfall extremes is assessed, again by a comparison with

  2. Theoretical Perspectives on Gender in Education: The Case of Eastern and Southern Africa

    NASA Astrophysics Data System (ADS)

    Mannathoko, Changu

    1999-11-01

    In recent years, throughout Eastern and Southern Africa, there has been a proliferation of research on gender in education. It is possible to point to a wide variety of publications, courses and programmes planned and organized by universities, national governments, international organizations, non-governmental organizations and the private sector relating to this field. This article examines the feminist and gender theories underpinning all these endeavors. The theories are assessed for their potential capacity to assist in elucidating the complex relationship between gender and development within the region.

  3. Cantharidin and demethylcantharidin (palasonin) content of blister beetles (Coleoptera: Meloidae) from southern Africa.

    PubMed

    Mebs, Dietrich; Pogoda, Werner; Schneider, Michael; Kauert, Gerold

    2009-03-15

    In two species of meloid beetles, Hycleus oculatus and Hycleus tinctus, from southern Africa, cantharidin and demethylcantharidin (palasonin) were assayed quantitatively. For cantharidin the mean value per specimen was about 1 mg for H. oculatus and 0.2 mg for H. tinctus, the mean palasonin concentration was 20 (H. oculatus) and 12 times (H. tinctus) lower, respectively. However, considerable individual variation in the cantharidin concentration was observed and values of more than 6 mg of this compound per beetle were measured pointing to the high risk of severe and even fatal poisoning when ingesting these insects. PMID:19708124

  4. Emissions of mercury in southern Africa derived from long-term observations at Cape Point, South Africa

    NASA Astrophysics Data System (ADS)

    Brunke, E.-G.; Ebinghaus, R.; Kock, H. H.; Labuschagne, C.; Slemr, F.

    2012-08-01

    Mercury emissions in South Africa have so far been estimated only by a bottom-up approach from activities and emission factors for different processes. In this paper we derive GEM/CO (GEM being gaseous elemental mercury, Hg0), GEM/CO2, GEM/CH4, CO/CO2, CH4/CO2, and CH4/CO emission ratios from plumes observed during long-term monitoring of these species at Cape Point between March 2007 and December 2009. The average observed GEM/CO, GEM/CO2, GEM/CH4, CO/CO2, CH4/CO2, and CH4/CO emission ratios were 2.40 ± 2.65 pg m-3 ppb-1 (n = 47), 62.7 ± 80.2 pg m-3 ppm-1 (n = 44), 3.61 ± 4.66 pg m-3 ppb-1 (n = 46), 35.6 ± 25.4 ppb ppm-1 (n = 52), 20.2 ± 15.5 ppb ppm-1 (n = 48), and 0.876 ± 1.106 ppb ppb-1 (n = 42), respectively. The observed CO/CO2, CH4/CO2, and CH4/CO emission ratios agree within the combined uncertainties of the observations and emissions with the ratios calculated from EDGAR (version 4.2) CO2, CO, and CH4 inventories for South Africa and southern Africa (South Africa, Lesotho, Swaziland, Namibia, Botswana, Zimbabwe, and Mozambique) in 2007 and 2008 (inventories for 2009 are not available yet). Total elemental mercury emission of 13.1, 15.2, and 16.1 t Hg yr-1 are estimated independently using the GEM/CO, GEM/CO2, and GEM/CH4 emission ratios and the annual mean CO, CO2, and CH4 emissions, respectively, of South Africa in 2007 and 2008. The average of these independent estimates of 14.8 t GEM yr-1 is much less than the total emission of 257 t Hg yr-1 shown by older inventories which are now considered to be wrong. Considering the uncertainties of our emission estimate, of the emission inventories, and the fact that emission of GEM represents 50-78 % of all mercury emissions, our estimate is comparable to the currently cited GEM emissions in 2004 and somewhat smaller than emissions in 2006. A further increase of mercury emissions due to increasing electricity consumption will lead to a more pronounced difference. A quantitative assessment of the difference

  5. Female economic activity in Rural Malawi

    PubMed Central

    Hyder, Asma; Behrman, Jere R.

    2015-01-01

    This study investigates economic activities and their determinants for women in households of rural Malawi, one of the poorest countries in Sub-Saharan Africa (SSA). Three waves of household panel data for years 2006, 2008 and 2010 from the Malawi Longitudinal Study of Families and Health (MLSFH) are used to examine female labor market participation. This study includes certain important characteristics of Malawian households i.e., polygamy, ethnicity, religion and self reported health status. The study reports five different labor market outcomes for women's participation i.e., agriculture related work, market & sales activities, cottage industry, other economic activities and out of the labor market. The study finds significant relationships between these five different labor market outcomes and age cohorts, ethnicity and marriage (monogamous or polygamous). PMID:26120564

  6. Condom Semiotics: Meaning and Condom Use in Rural Malawi

    ERIC Educational Resources Information Center

    Tavory, Iddo; Swidler, Ann

    2009-01-01

    This article examines the widespread resistance to condom use in sub-Saharan Africa by describing the major semiotic axes that organize how people talk about condoms and condom use. These axes include the "sweetness" of sex, trust and love between sexual partners, and assessments of risk and danger. Using data from rural Malawi, we show that…

  7. Local biomass burning is a dominant cause of the observed precipitation reduction in southern Africa

    PubMed Central

    Hodnebrog, Øivind; Myhre, Gunnar; Forster, Piers M.; Sillmann, Jana; Samset, Bjørn H.

    2016-01-01

    Observations indicate a precipitation decline over large parts of southern Africa since the 1950s. Concurrently, atmospheric concentrations of greenhouse gases and aerosols have increased due to anthropogenic activities. Here we show that local black carbon and organic carbon aerosol emissions from biomass burning activities are a main cause of the observed decline in southern African dry season precipitation over the last century. Near the main biomass burning regions, global and regional modelling indicates precipitation decreases of 20–30%, with large spatial variability. Increasing global CO2 concentrations further contribute to precipitation reductions, somewhat less in magnitude but covering a larger area. Whereas precipitation changes from increased CO2 are driven by large-scale circulation changes, the increase in biomass burning aerosols causes local drying of the atmosphere. This study illustrates that reducing local biomass burning aerosol emissions may be a useful way to mitigate reduced rainfall in the region. PMID:27068129

  8. Enhancing malaria control using a computerised management system in southern Africa

    PubMed Central

    Booman, Marlize; Sharp, Brian L; Martin, Carrin L; Manjate, Bonifacio; la Grange, Jacobus J; Durrheim, David N

    2003-01-01

    Background Malaria control programmes utilising indoor residual spraying are only effective if a high coverage of targeted structures is achieved and an insecticide that is effective against the specific mosquito vector is correctly applied. Ongoing monitoring of spraying operations is essential to assure optimal programme performance and early corrective action, where indicated. Methods Successful development and application of a computerised spraying operations management system in Mpumalanga Province, South Africa during 1998 resulted in its adaptation and introduction in neighbouring Maputo Province, southern Mozambique during 2000. The structure and components of this computerised management system are described, and its' operational benefit in southern Mozambique, where community-based spray operators apply intradomiciliary insecticide, are reviewed. Conclusions The computerised management system allowed malaria programme management and field supervisors to monitor spraying coverage, insecticide consumption and application rates on an ongoing basis. The system supported a successful transition to community-based spraying, while assuring correct insecticide application and spraying completion according to schedule. PMID:12816547

  9. Local biomass burning is a dominant cause of the observed precipitation reduction in southern Africa.

    PubMed

    Hodnebrog, Øivind; Myhre, Gunnar; Forster, Piers M; Sillmann, Jana; Samset, Bjørn H

    2016-01-01

    Observations indicate a precipitation decline over large parts of southern Africa since the 1950s. Concurrently, atmospheric concentrations of greenhouse gases and aerosols have increased due to anthropogenic activities. Here we show that local black carbon and organic carbon aerosol emissions from biomass burning activities are a main cause of the observed decline in southern African dry season precipitation over the last century. Near the main biomass burning regions, global and regional modelling indicates precipitation decreases of 20-30%, with large spatial variability. Increasing global CO2 concentrations further contribute to precipitation reductions, somewhat less in magnitude but covering a larger area. Whereas precipitation changes from increased CO2 are driven by large-scale circulation changes, the increase in biomass burning aerosols causes local drying of the atmosphere. This study illustrates that reducing local biomass burning aerosol emissions may be a useful way to mitigate reduced rainfall in the region. PMID:27068129

  10. Local biomass burning is a dominant cause of the observed precipitation reduction in southern Africa

    NASA Astrophysics Data System (ADS)

    Hodnebrog, Øivind; Myhre, Gunnar; Forster, Piers M.; Sillmann, Jana; Samset, Bjørn H.

    2016-04-01

    Observations indicate a precipitation decline over large parts of southern Africa since the 1950s. Concurrently, atmospheric concentrations of greenhouse gases and aerosols have increased due to anthropogenic activities. Here we show that local black carbon and organic carbon aerosol emissions from biomass burning activities are a main cause of the observed decline in southern African dry season precipitation over the last century. Near the main biomass burning regions, global and regional modelling indicates precipitation decreases of 20-30%, with large spatial variability. Increasing global CO2 concentrations further contribute to precipitation reductions, somewhat less in magnitude but covering a larger area. Whereas precipitation changes from increased CO2 are driven by large-scale circulation changes, the increase in biomass burning aerosols causes local drying of the atmosphere. This study illustrates that reducing local biomass burning aerosol emissions may be a useful way to mitigate reduced rainfall in the region.

  11. Country watch: Malawi.

    PubMed

    Knox, G

    1995-01-01

    The Drought Network for information sharing eventually led to the establishment of the more formal Southern Region AIDS Network (SORAN) where representatives from government and nongovernmental organizations (NGOs) focused on awareness raising, lobbying, and advocacy. As an initial step towards networking on HIV/AIDS issues, a festival was organized in Blantyre on December 4, 1993, by NGOs, private companies, church groups, school children, and volunteers to bring about behavior change. About 2000 people gathered to listen to music, learn about HIV transmission through drama group presentations, watch videos with HIV/STD prevention messages, and learn about proper condom use. The participants officially established SORAN in February 1994 to act as a coordinating body for organizations working in prevention and care for HIV/STD-infected persons and their families. Network activities endeavored: to assist organizations interested in developing HIV/AIDS programs and activities; to encourage the business communities to participate in multisectoral coordination and to help channel funds from them to HIV/AIDS programs; to act as a resource center for information about HIV/AIDS; and to lobby among politicians as well as traditional local and religious leaders. When the first multi-party parliamentary election approached in May 1994, SORAN challenged representatives of 7 political parties and a women's organization to speak out publicly on what they envisioned doing about HIV/AIDS. The Grand Walk was also organized by SORAN members representing the Catholic Episcopal Conference of Malawi, the Protestant Blantyre Synod, a local brewery, and UNICEF. About 500 walkers received support from passersby. 70% were school children 10-18 years old who sang AIDS awareness songs and passed out flyers. Three months later the National AIDS Program's Big Walk for AIDS, following a National AIDS Crisis Conference, signaled the government's public recognition of the need for a

  12. Revised timeline and distribution of the earliest diverged human maternal lineages in southern Africa.

    PubMed

    Chan, Eva K F; Hardie, Rae-Anne; Petersen, Desiree C; Beeson, Karen; Bornman, Riana M S; Smith, Andrew B; Hayes, Vanessa M

    2015-01-01

    The oldest extant human maternal lineages include mitochondrial haplogroups L0d and L0k found in the southern African click-speaking forager peoples broadly classified as Khoesan. Profiling these early mitochondrial lineages allows for better understanding of modern human evolution. In this study, we profile 77 new early-diverged complete mitochondrial genomes and sub-classify another 105 L0d/L0k individuals from southern Africa. We use this data to refine basal phylogenetic divergence, coalescence times and Khoesan prehistory. Our results confirm L0d as the earliest diverged lineage (∼172 kya, 95%CI: 149-199 kya), followed by L0k (∼159 kya, 95%CI: 136-183 kya) and a new lineage we name L0g (∼94 kya, 95%CI: 72-116 kya). We identify two new L0d1 subclades we name L0d1d and L0d1c4/L0d1e, and estimate L0d2 and L0d1 divergence at ∼93 kya (95%CI:76-112 kya). We concur the earliest emerging L0d1'2 sublineage L0d1b (∼49 kya, 95%CI:37-58 kya) is widely distributed across southern Africa. Concomitantly, we find the most recent sublineage L0d2a (∼17 kya, 95%CI:10-27 kya) to be equally common. While we agree that lineages L0d1c and L0k1a are restricted to contemporary inland Khoesan populations, our observed predominance of L0d2a and L0d1a in non-Khoesan populations suggests a once independent coastal Khoesan prehistory. The distribution of early-diverged human maternal lineages within contemporary southern Africans suggests a rich history of human existence prior to any archaeological evidence of migration into the region. For the first time, we provide a genetic-based evidence for significant modern human evolution in southern Africa at the time of the Last Glacial Maximum at between ∼21-17 kya, coinciding with the emergence of major lineages L0d1a, L0d2b, L0d2d and L0d2a. PMID:25807545

  13. Revised Timeline and Distribution of the Earliest Diverged Human Maternal Lineages in Southern Africa

    PubMed Central

    Chan, Eva K. F.; Hardie, Rae-Anne; Petersen, Desiree C.; Beeson, Karen; Bornman, Riana M. S.; Smith, Andrew B.; Hayes, Vanessa M.

    2015-01-01

    The oldest extant human maternal lineages include mitochondrial haplogroups L0d and L0k found in the southern African click-speaking forager peoples broadly classified as Khoesan. Profiling these early mitochondrial lineages allows for better understanding of modern human evolution. In this study, we profile 77 new early-diverged complete mitochondrial genomes and sub-classify another 105 L0d/L0k individuals from southern Africa. We use this data to refine basal phylogenetic divergence, coalescence times and Khoesan prehistory. Our results confirm L0d as the earliest diverged lineage (∼172 kya, 95%CI: 149–199 kya), followed by L0k (∼159 kya, 95%CI: 136–183 kya) and a new lineage we name L0g (∼94 kya, 95%CI: 72–116 kya). We identify two new L0d1 subclades we name L0d1d and L0d1c4/L0d1e, and estimate L0d2 and L0d1 divergence at ∼93 kya (95%CI:76–112 kya). We concur the earliest emerging L0d1’2 sublineage L0d1b (∼49 kya, 95%CI:37–58 kya) is widely distributed across southern Africa. Concomitantly, we find the most recent sublineage L0d2a (∼17 kya, 95%CI:10–27 kya) to be equally common. While we agree that lineages L0d1c and L0k1a are restricted to contemporary inland Khoesan populations, our observed predominance of L0d2a and L0d1a in non-Khoesan populations suggests a once independent coastal Khoesan prehistory. The distribution of early-diverged human maternal lineages within contemporary southern Africans suggests a rich history of human existence prior to any archaeological evidence of migration into the region. For the first time, we provide a genetic-based evidence for significant modern human evolution in southern Africa at the time of the Last Glacial Maximum at between ∼21–17 kya, coinciding with the emergence of major lineages L0d1a, L0d2b, L0d2d and L0d2a. PMID:25807545

  14. Impact of immigration on HIV-1 molecular epidemiology in West Africa, Maghreb and Southern Europe.

    PubMed

    Miri, Lamia; Wakrim, Lahcen; Kassar, Hassène; Hemminki, Kari; Khyatti, Meriem

    2014-01-01

    There is global concern about the relation between international migration and the course of the AIDS epidemic. Maghreb is a North African region, which lies between sub-Saharan Africa and Europe. It has been turned recently into a region of immigration, since there are more and more flows of West African migrants hoping to reach European countries. Here we provide an overview on HIV-1 molecular epidemiology particularly in West African countries, Maghreb (Morocco, Algeria, Tunisia) and southern European countries (Spain, France, and Italy). The studies conducted in several countries of the region revealed different features of HIV-1 molecular epidemiology, especially for the distribution of viral subtypes and for transmitted drug resistance profiles. Furthermore, migration from West Africa to Europe seems to be a potential source of non-B subtype mobility to Maghreb and eventually to southern Europe, where HIV-1 non-B variants significantly increased in the last 10 to 15 years. As genetic differences between subtypes might impact the drug resistance pathways, it is important to provide continuous surveillance programs for the early detection of new variants spreading in the population before they become more prevalent, and to identify resistance profiles in different infected populations, especially migrants. PMID:24802562

  15. The Arabian Cradle: Mitochondrial Relicts of the First Steps along the Southern Route out of Africa

    PubMed Central

    Fernandes, Verónica; Alshamali, Farida; Alves, Marco; Costa, Marta D.; Pereira, Joana B.; Silva, Nuno M.; Cherni, Lotfi; Harich, Nourdin; Cerny, Viktor; Soares, Pedro; Richards, Martin B.; Pereira, Luísa

    2012-01-01

    A major unanswered question regarding the dispersal of modern humans around the world concerns the geographical site of the first human steps outside of Africa. The “southern coastal route” model predicts that the early stages of the dispersal took place when people crossed the Red Sea to southern Arabia, but genetic evidence has hitherto been tenuous. We have addressed this question by analyzing the three minor west-Eurasian haplogroups, N1, N2, and X. These lineages branch directly from the first non-African founder node, the root of haplogroup N, and coalesce to the time of the first successful movement of modern humans out of Africa, ∼60 thousand years (ka) ago. We sequenced complete mtDNA genomes from 85 Southwest Asian samples carrying these haplogroups and compared them with a database of 300 European examples. The results show that these minor haplogroups have a relict distribution that suggests an ancient ancestry within the Arabian Peninsula, and they most likely spread from the Gulf Oasis region toward the Near East and Europe during the pluvial period 55–24 ka ago. This pattern suggests that Arabia was indeed the first staging post in the spread of modern humans around the world. PMID:22284828

  16. Rapid population growth. Effects on the social infrastructures of southern Africa.

    PubMed

    Smith, J D

    1995-01-01

    Southern Africa's high rate of population growth and widespread poverty have serious implications for the region's social infrastructure. Large increases in the school-age population have undermined efforts to improve the quality of education since all resources are directed toward expansion of availability. To achieve a teacher-pupil ratio of 1:40 at the primary level and 1:35 at the secondary level, an estimated additional 50,000 classrooms would be required. Also jeopardized by high fertility is access to health services, safe water, and sanitation. In Mozambique, for example, where only 30% of the population has access to health services, the under-five years mortality rate is 297/1000 live births and the physician-population ratio is 1:37,970. Substandard housing, homelessness, congestion, deteriorating public services, pollution, and crime dominate urban areas. The single most effective intervention to reduce population growth in Southern Africa is female education. Women without a secondary education bear an average of seven children; if 40% of women attend secondary school, this drops to three children. Thus, governments must make gender equality a central focus of development planning and ensure that women are participants in this process. Property and inheritance laws that serve to increase the economic need for early marriage should be eliminated. Public health programs, including family planning, must be expanded. Finally, women's organizations should be strengthened and urged to foster female empowerment. PMID:12346213

  17. Late Quaternary dietary shifts of the Cape grysbok ( Raphicerus melanotis) in southern Africa

    NASA Astrophysics Data System (ADS)

    Faith, J. Tyler

    2011-01-01

    The Cape grysbok is endemic to southern Africa's Cape Floral Region where it selectively browses various species of dicotyledonous vegetation. Fossil evidence indicates that the grysbok persisted under glacial and interglacial conditions throughout the late Quaternary and inhabited a range of environments. This study employs mesowear analysis to reconstruct grysbok diets over time and in response to changing environments at Nelson Bay Cave, Die Kelders Cave 1, Klasies River Mouth, and Swartklip 1. Results indicate that the amount of grasses (monocots) versus leafy vegetation (dicots) included in the diet fluctuated over time and largely in agreement with changes in faunal community structure. The case for dietary flexibility is particularly clear at Nelson Bay Cave, where there is a significant trend from mixed feeding towards increased browsing from the late Pleistocene (~ 18,500 14C yr BP) through the Holocene. Dietary shifts at Nelson Bay Cave are consistent with the hypothesis that declining grassland productivity is responsible for the terminal Pleistocene extinction of several large ungulates in southern Africa. Furthermore, the short-term dietary shifts demonstrated here (100s to 1000s of years) provide an important caution against relying on taxonomic uniformitarianism when reconstructing the dietary preferences of fossil ungulates, both extant and extinct.

  18. Migration and health in Southern Africa: 100 years and still circulating

    PubMed Central

    Lurie, Mark N.; Williams, Brian G.

    2014-01-01

    Migration has deep historical roots in South and Southern Africa and to this day continues to be highly prevalent and a major factor shaping South African society and health. In this paper we examine the role of migration in the spread of two diseases nearly 100 years apart: tuberculosis following the discovery of gold in 1886 and HIV in the early 1990s. Both cases demonstrate the critical role played by human migration in the transmission and subsequent dissemination of these diseases to rural areas. In both cases, migration acts to assemble in one high-risk environment thousands of young men highly susceptible to new diseases. With poor living and working conditions, these migration destinations act as hot-spots for disease transmission. Migration of workers back to rural areas then serves as a highly efficient means of disseminating these diseases to rural populations. We conclude by raising some more recent questions examining the current role of migration in Southern Africa. PMID:24653964

  19. Maintenance payments for child support in southern Africa: using law to promote family planning.

    PubMed

    Armstrong, A

    1992-01-01

    This article presents some of the legal, social, cultural, and practical constraints facing women who attempt to enforce their right to maintenance (child support) payments in southern Africa. It is based on research by the Women and Law in Southern Africa Trust, a network of women who research women's legal rights in six countries: Botswana, Lesotho, Mozambique, Swaziland, Zambia, and Zimbabwe. Statutes in all countries in the region provide that a man must support his legitimate and illegitimate children; there are, however, weaknesses in the laws on the books. The social and cultural constraints that influence the enforcement of maintenance laws include women's lack of knowledge of the law, attitudes toward child support influenced by customary law, allegations of women's abuse of maintenance payments, financial and practical problems, and fear of physical violence or other forms of retribution. Maintenance laws are relevant to family planning in that if such laws were more effectively enforced, so that the financial burden of children were more equally shared between women and men, men would have a financial stake in controlling their fertility. PMID:1412595

  20. Culture, sexuality, and women's agency in the prevention of HIV/AIDS in southern Africa.

    PubMed Central

    Susser, I; Stein, Z

    2000-01-01

    Using an ethnographic approach, the authors explored the awareness among women in southern Africa of the HIV epidemic and the methods they might use to protect themselves from the virus. The research, conducted from 1992 through 1999, focused specifically on heterosexual transmission in 5 sites that were selected to reflect urban and rural experiences, various populations, and economic and political opportunities for women at different historical moments over the course of the HIV epidemic. The authors found that the female condom and other woman-controlled methods are regarded as culturally appropriate among many men and women in southern Africa and are crucial to the future of HIV/AIDS prevention. The data reported in this article demonstrate that cultural acceptability for such methods among women varies along different axes, both over time and among different populations. For this reason, local circumstances need to be taken into account. Given that women have been clearly asking for protective methods they can use, however, political and economic concerns, combined with historically powerful patterns of gender discrimination and neglect of women's sexuality, must be viewed as the main obstacles to the development and distribution of methods women can control. PMID:10897180

  1. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened. PMID:25929961

  2. The SASSCAL contribution to climate observation, climate data management and data rescue in Southern Africa

    NASA Astrophysics Data System (ADS)

    Kaspar, F.; Helmschrot, J.; Mhanda, A.; Butale, M.; de Clercq, W.; Kanyanga, J. K.; Neto, F. O. S.; Kruger, S.; Castro Matsheka, M.; Muche, G.; Hillmann, T.; Josenhans, K.; Posada, R.; Riede, J.; Seely, M.; Ribeiro, C.; Kenabatho, P.; Vogt, R.; Jürgens, N.

    2015-07-01

    A major task of the newly established "Southern African Science Service Centre for Climate Change and Adaptive Land Management" (SASSCAL; www.sasscal.org) and its partners is to provide science-based environmental information and knowledge which includes the provision of consistent and reliable climate data for Southern Africa. Hence, SASSCAL, in close cooperation with the national weather authorities of Angola, Botswana, Germany and Zambia as well as partner institutions in Namibia and South Africa, supports the extension of the regional meteorological observation network and the improvement of the climate archives at national level. With the ongoing rehabilitation of existing weather stations and the new installation of fully automated weather stations (AWS), altogether 105 AWS currently provide a set of climate variables at 15, 30 and 60 min intervals respectively. These records are made available through the SASSCAL WeatherNet, an online platform providing near-real time data as well as various statistics and graphics, all in open access. This effort is complemented by the harmonization and improvement of climate data management concepts at the national weather authorities, capacity building activities and an extension of the data bases with historical climate data which are still available from different sources. These activities are performed through cooperation between regional and German institutions and will provide important information for climate service related activities.

  3. Three genetic groups of the Eucalyptus stem canker pathogen Teratosphaeria zuluensis introduced into Africa from an unknown source.

    PubMed

    Jimu, Luke; Chen, ShuaiFei; Wingfield, Michael J; Mwenje, Eddie; Roux, Jolanda

    2016-01-01

    The Eucalyptus stem canker pathogen Teratosphaeria zuluensis was discovered in South Africa in 1988 and it has subsequently been found in several other African countries as well as globally. In this study, the population structure, genetic diversity and evolutionary history of T. z uluensis were analysed using microsatellite markers to gain an enhanced understanding of its movement in Africa. Isolates were collected from several sites in Malawi, Mozambique, Uganda and Zambia. Data obtained were compared with those previously published for a South African population. The data obtained from 334 isolates, amplified across eight microsatellite loci, were used for assignment, differentiation and genetic diversity tests. STRUCTURE analyses, θ st and genetic distances revealed the existence of two clusters, one dominated by isolates from South Africa and the other by isolates from the Zambezi basin including Malawi, Mozambique and Zambia. High levels of admixture were found within and among populations, dominated by the Mulanje population in Malawi. Moderate to low genetic diversity of the populations supports the previously held view that the pathogen was introduced into Africa. The clonal nature of the Ugandan population suggests a very recent introduction, most likely from southern Africa. PMID:26499489

  4. Coexisting shortening and extension along the "Africa-Eurasia" plate boundary in southern Italy

    NASA Astrophysics Data System (ADS)

    Cuffaro, M.; Riguzzi, F.; Scrocca, D.; Doglioni, C.

    2009-04-01

    We performed geodetic strain rate field analyses along the "Africa (Sicily microplate)"-"Eurasia (Tyrrhenian microplate)" plate boundary in Sicily (southern Italy), using new GPS velocities from a data set spanning maximum ten years (1998-2007). Data from GPS permanent stations maintained from different institutions and the recent RING network, settled in Italy in the last five years by the Istituto Nazionale di Geofisica e Vulcanologia, were included into the analysis. Two dimensional strain and rotation rate fields were estimated by the distance weighted approach on a regularly spaced grid (30*30km), estimating the strain using all stations, but data from each station are weighted by their distance from the grid node by a constant a=70km that specifies how the effect of a station decays with distance from the node grid interpolation. Results show that most of the shortening of the Africa-Eurasia relative motion is distributed in the northwestern side offshore Sicily, whereas the extension becomes comparable with shortening on the western border of the Capo d'Orlando basin, and grater in the northeastern side, offshore Sicily, as directly provided by GPS velocities which show a larger E-ward component of sites located in Calabria with respect to those located either in northern Sicily or in the Ustica-Aeolian islands. Moreover, where shortening and extension have mostly a similar order of magnitude, two rotation rate fields can be detected, CCW in the northwestern side of Sicily, and CW in the northeastern one respectively. Also, 2-D dilatation field records a similar pattern, with negative values (shortening) in the northwestern area of Sicily close to the Ustica island, and positive values (extension) in the northeastern and southeastern ones, respectively. Principal shortening and extension rate axes are consistent with long-term geological features: seismic reflection profiles acquired in the southern Tyrrhenian seismogenic belt show active extensional faults

  5. Distributions of Trace Gases and Aerosols during the Dry Biomass Burning Season in Southern Africa

    NASA Technical Reports Server (NTRS)

    Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Blake, Donald R.; Gao, Song; Kirchstetter, Thomas W.

    2003-01-01

    Vertical profiles in the lower troposphere of temperature, relative humidity, sulfur dioxide (SO2), ozone (O3), condensation nuclei (CN), and carbon monoxide (CO), and horizontal distributions of twenty gaseous and particulate species, are presented for five regions of southern Africa during the dry biomass burning season of 2000. The regions are the semiarid savannas of northeast South Africa and northern Botswana, the savanna-forest mosaic of coastal Mozambique, the humid savanna of southern Zambia, and the desert of western Namibia. The highest average concentrations of carbon dioxide (CO2), CO, methane (CH4), O3, black particulate carbon, and total particulate carbon were in the Botswana and Zambia sectors (388 and 392 ppmv, 369 and 453 ppbv, 1753 and 1758 ppbv, 79 and 88 ppbv, 2.6 and 5.5 micrograms /cubic meter and 13.2 and 14.3 micrograms/cubic meter). This was due to intense biomass burning in Zambia and surrounding regions. The South Africa sector had the highest average concentrations of SO2, sulfate particles, and CN (5.1 ppbv, 8.3 micrograms/cubic meter, and per 6400 cubic meter , respectively), which derived from biomass burning and electric generation plants and mining operations within this sector. Air quality in the Mozambique sector was similar to the neighboring South Africa sector. Over the arid Namibia sector there were polluted layers aloft, in which average SO2, O3, and CO mixing ratios (1.2 ppbv, 76 ppbv, and 3 10 ppbv, respectively) were similar to those measured over the other more polluted sectors. This was due to transport of biomass smoke from regions of widespread savanna burning in southern Angola. Average concentrations over all sectors of CO2 (386 +/- 8 ppmv), CO (261 +/- 81 ppbv), SO2 (2.5 +/- 1.6 ppbv), O3 (64 +/- 13 ppbv), black particulate carbon (2.3 +/- 1.9 microgram/cubic meter), organic particulate carbon (6.2 +/- 5.2 microgram/cubic meter), total particle mass (26.0 +/- 4.7 microgram/cubic meter), and potassium particles (0

  6. Clear the Mind of Pre-Conceived Ideas and Get Your Hands Dirty! An Approach to Field-Based Courses: The SLUSE-Southern Africa Experience

    ERIC Educational Resources Information Center

    Hill, Trevor R.; Traynor, Catherine H.; Birch-Thomsen, Torben; De Neergaard, Andreas; Bob, Urmilla; Manyatsi, Absalom M.; Sebego, Reuben J.

    2008-01-01

    This paper explores an approach to problem-oriented, interdisciplinary field-based courses devised by university consortia in southern Africa and Denmark. The SLUSE (Sustainable Land Use and Natural Resource Management) model has been applied on six three-week field courses within southern Africa and trained over 200 students. Student groups…

  7. Oil and gas developments in central and southern Africa in 1981

    SciTech Connect

    McGrew, H.J.

    1982-11-01

    Exploratory activity in central and southern Africa continued to grow during 1981. Geophysical operations reached nearly record levels and the number of wells increased markedly. Oil production suffered from the adverse conditions that existed throughout the world and dropped by a significant amount. New Concession acquisitions occurred in several of the countries in northeast Africa. Elsewhere, the operating companies negotiated new concessions and renewed those that were expiring. In several countries where production has been proven, the operators were assigned exploitation concessions. Seismic crews and marine geophysical vessels were active throughout the countries in this area. A total of 365 party-months of work was done to yield 98,035 km of new lines. A moderate amount of 3-D recording was carried out in connection with field development. Some aeromagnetic work was done, principally in northeast Africa and in Mozambique. Forty-four new fields or pools were discovered by drilling 115 new-field wildcat and exploratory wells. These wells accounted for 1,060,254 ft (323,248 m) of hole. Appraisal and development drilling resulted in 321 wells with a total of 2,533,305 ft (772,349 m) of hole drilled. At year end, 25 exploratory wells were under way or resting, and 49 rigs were active in development drilling. Oil production for the year was 691,995,939 bbl, a decrease of nearly 25% from 1980. Nigeria suffered the greatest drop in production; however, increases were achieved in Cameroon, Congo, and Zaire. The cumulative production from this part of Africa passed the 10 billion bbl mark.

  8. An Archeomagnetic Record From Southern Africa and its Bearing on the History of the South Atlantic Anomaly

    NASA Astrophysics Data System (ADS)

    Grigsby, M. R.; Tarduno, J. A.; Cottrell, R. D.; Huffman, T. N.; Watkeys, M. K.; Blackman, E.

    2015-12-01

    The low intensity area in Earth's recent magnetic field that spans the southern Atlantic Ocean, Africa and South America is commonly called the South Atlantic Anomaly (SAA). Many believe the SAA is linked to the dramatic decay of the dipole geomagnetic field intensity during the last 160 years, and the growth of a reversed core flux patch beneath South Africa. The dipole field decay has even motivated speculation that Earth is heading toward a geomagnetic field reversal. But understanding these phenomena within the context of longer-term geomagnetic history has been limited by a lack of Southern Hemisphere archeomagnetic data. We have recently presented the first archeomagnetic data from Iron Age sites of southern Africa (~1000-1650 AD) (Tarduno et al., 2014, 2015). Magnetic data show a sharp intensity drop at ~1300 AD, at a rate comparable to modern field changes in the SAA, (but to lower values). These changes motivated our conceptual model whereby the recurrence of low field values reflects magnetic flux expulsion from the core, promoted by the unusual core-mantle boundary composition and structure beneath southern Africa defined by seismology (specifically the African Large Low Velocity Seismic Province, or LLVSP). Because the African LLVSP is a longstanding structure, we expect this region to be a steady site of flux expulsion, and perhaps the triggering site for reversals, on time scales of millions of years. Here we discuss our ongoing efforts to extend the archeomagnetic record from southern Africa back in time, and further develop the flux expulsion- African LLVSP hypothesis, through new sampling and paleomagnetic analyses of Iron Age burnt huts, grain bins and kraals from South Africa, Zimbabwe and Botswana.

  9. Specialization training in Malawi: a qualitative study on the perspectives of medical students graduating from the University of Malawi College of Medicine

    PubMed Central

    2014-01-01

    Background There is a critical shortage of healthcare workers in sub-Saharan Africa, and Malawi has one of the lowest physician densities in the region. One of the reasons for this shortage is inadequate retention of medical school graduates, partly due to the desire for specialization training. The University of Malawi College of Medicine has developed specialty training programs, but medical school graduates continue to report a desire to leave the country for specialization training. To understand this desire, we studied medical students’ perspectives on specialization training in Malawi. Methods We conducted semi-structured interviews of medical students in the final year of their degree program. We developed an interview guide through an iterative process, and recorded and transcribed all interviews for analysis. Two independent coders coded the manuscripts and assessed inter-coder reliability, and the authors used an “editing approach” to qualitative analysis to identify and categorize themes relating to the research aim. The University of Pittsburgh Institutional Review Board and the University of Malawi College of Medicine Research and Ethics Committee approved this study and authors obtained written informed consent from all participants. Results We interviewed 21 medical students. All students reported a desire for specialization training, with 12 (57%) students interested in specialties not currently offered in Malawi. Students discussed reasons for pursuing specialization training, impressions of specialization training in Malawi, reasons for staying or leaving Malawi to pursue specialization training and recommendations to improve training. Conclusions Graduating medical students in Malawi have mixed views of specialization training in their own country and still desire to leave Malawi to pursue further training. Training institutions in sub-Saharan Africa need to understand the needs of the country’s healthcare workforce and the needs of their

  10. Perceptions of voluntary medical male circumcision among circumcising and non-circumcising communities in Malawi

    PubMed Central

    Rennie, Stuart; Perry, Brian; Corneli, Amy; Chilungo, Abdullah; Umar, Eric

    2015-01-01

    Three randomised controlled trials in Africa indicated that voluntary medical male circumcision (VMMC) is an effective method to reduce a man’s risk of becoming infected through sex with an HIV-positive female partner. The success of recent public health initiatives to increase numbers of circumcised men in Malawi has been very limited. We conducted in-depth interviews (IDIs) and focus group discussions (FGDs) with men, women, and male adolescents from non-circumcising and circumcising communities in southern Malawi to better understand their beliefs about male circumcision and the promotion of VMMC for HIV prevention. Results revealed that beliefs about male circumcision, in general, are strongly mediated by Malawian culture and history. Participants have attempted to develop a new meaning for circumcision in light of the threat of HIV infection and the publicised risk reduction benefits of VMMC. Several study participants found it difficult to distinguish VMMC from traditional circumcision practices (jando and lupanda), despite awareness that the new form of circumcision was an expression of (western) modern medicine performed largely for public health purposes. Greater recognition of background cultural beliefs and practices could inform future efforts to promote medical male circumcision as an HIV prevention strategy in this context. PMID:25630610

  11. Rainfall variability and extremes over southern Africa: Assessment of a climate model to reproduce daily extremes

    NASA Astrophysics Data System (ADS)

    Williams, C. J. R.; Kniveton, D. R.; Layberry, R.

    2009-04-01

    It is increasingly accepted that that any possible climate change will not only have an influence on mean climate but may also significantly alter climatic variability. A change in the distribution and magnitude of extreme rainfall events (associated with changing variability), such as droughts or flooding, may have a far greater impact on human and natural systems than a changing mean. This issue is of particular importance for environmentally vulnerable regions such as southern Africa. The subcontinent is considered especially vulnerable to and ill-equipped (in terms of adaptation) for extreme events, due to a number of factors including extensive poverty, famine, disease and political instability. Rainfall variability and the identification of rainfall extremes is a function of scale, so high spatial and temporal resolution data are preferred to identify extreme events and accurately predict future variability. The majority of previous climate model verification studies have compared model output with observational data at monthly timescales. In this research, the assessment of ability of a state of the art climate model to simulate climate at daily timescales is carried out using satellite derived rainfall data from the Microwave Infra-Red Algorithm (MIRA). This dataset covers the period from 1993-2002 and the whole of southern Africa at a spatial resolution of 0.1 degree longitude/latitude. The ability of a climate model to simulate current climate provides some indication of how much confidence can be applied to its future predictions. In this paper, simulations of current climate from the UK Meteorological Office Hadley Centre's climate model, in both regional and global mode, are firstly compared to the MIRA dataset at daily timescales. This concentrates primarily on the ability of the model to simulate the spatial and temporal patterns of rainfall variability over southern Africa. Secondly, the ability of the model to reproduce daily rainfall extremes will

  12. Evolutionary analysis of foot-and-mouth disease virus serotype SAT 1 isolates from east africa suggests two independent introductions from southern africa

    PubMed Central

    2010-01-01

    Background In East Africa, foot-and-mouth disease virus serotype SAT 1 is responsible for occasional severe outbreaks in livestock and is known to be maintained within the buffalo populations. Little is known about the evolutionary forces underlying its epidemiology in the region. To enhance our appreciation of the epidemiological status of serotype SAT 1 virus in the region, we inferred its evolutionary and phylogeographic history by means of genealogy-based coalescent methods using 53 VP1 coding sequences covering a sampling period from 1948-2007. Results The VP1 coding sequence of 11 serotype SAT 1 FMD viruses from East Africa has been determined and compared with known sequences derived from other SAT 1 viruses from sub-Saharan Africa. Purifying (negative) selection and low substitution rates characterized the SAT 1 virus isolates in East Africa. Two virus groups with probable independent introductions from southern Africa were identified from a maximum clade credibility tree. One group was exclusive to Uganda while the other was present within Kenya and Tanzania. Conclusions Our results provide a baseline characterization of the inter-regional spread of SAT 1 in sub-Saharan Africa and highlight the importance of a regional approach to trans-boundary animal disease control in order to monitor circulating strains and apply appropriate vaccines. PMID:21118525

  13. History and origin of the HIV-1 subtype C epidemic in South Africa and the greater southern African region

    PubMed Central

    Wilkinson, Eduan; Engelbrecht, Susan; de Oliveira, Tulio

    2015-01-01

    HIV has spread at an alarming rate in South Africa, making it the country with the highest number of HIV infections. Several studies have investigated the histories of HIV-1 subtype C epidemics but none have done so in the context of social and political transformation in southern Africa. There is a need to understand how these processes affects epidemics, as socio-political transformation is a common and on-going process in Africa. Here, we genotyped strains from the start of the epidemic and applied phylodynamic techniques to determine the history of the southern Africa and South African epidemic from longitudinal sampled data. The southern African epidemic’s estimated dates of origin was placed around 1960 (95% HPD 1956–64), while dynamic reconstruction revealed strong growth during the 1970s and 80s. The South African epidemic has a similar origin, caused by multiple introductions from neighbouring countries, and grew exponentially during the 1980s and 90s, coinciding with socio-political changes in South Africa. These findings provide an indication as to when the epidemic started and how it has grown, while the inclusion of sequence data from the start of the epidemic provided better estimates. The epidemic have stabilized in recent years with the expansion of antiretroviral therapy. PMID:26574165

  14. Prediction, Assessment of the Rift Valley fever Activity in East and Southern Africa 2006 - 2008 and Possible Vector Control Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historical outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns of the El Nino/Southern Oscillation (ENSO) phenomenon which results in elevated and widespread rainfall over the RVF endemic areas of Africa. Using satellite measurements of global and ...

  15. Social and Economic Change in Southern Africa. Fulbright-Hays Summer Seminars Abroad Program, Summer 1991. [Curriculum Projects and Papers.

    ERIC Educational Resources Information Center

    Institute of International Education, New York, NY.

    This document presents curriculum projects and papers written by U.S. teachers who traveled to countries in Southern Africa in the summer of 1991 as part of the Fulbright-Hays Summer Seminars Abroad Program. The included projects and papers are: "Through a Glass Darkly: The Enigmatic Educational System of Botswana" (Alan C. Howard); "Creating…

  16. Working with Cultural-Historical Activity Theory and Critical Realism to Investigate and Expand Farmer Learning in Southern Africa

    ERIC Educational Resources Information Center

    Mukute, Mutizwa; Lotz-Sisitka, Heila

    2012-01-01

    This article uses the theoretical and methodological tools of cultural historical activity theory and critical realism to examine three case studies of the introduction and expansion of sustainable agricultural practices in southern Africa. The article addresses relevant issues in the field of agricultural extension, which lacks a theoretical…

  17. Prediction, Assessment of the Rift Valley Fever Activity in East and Southern Africa 2006 - 2008 and Possible Vector Control Strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Historical episodic outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns (El Niño and La Niña) of El Niño Southern Oscillation (ENSO) phenomenon which results in elevated and widespread rainfall over the RVF endemic areas of Africa. Using satellite ...

  18. Vernonieae (Asteraceae) of southern Africa: A generic disposition of the species and a study of their pollen

    PubMed Central

    Robinson, Harold; Skvarla, John J.; Funk, Vicki A.

    2016-01-01

    Abstract Current and previously included members of the Tribe Vernonieae (Asteraceae) of southern Africa are listed in their presently recognized genera with complete synonymies and keys to genera and species. The genus Vernonia, as presently delimited, does not occur in Africa. Genera of the Vernonieae presently recognized from southern Africa are Baccharoides, Bothriocline, Cyanthillium, Distephanus, Erlangea, Ethulia, Gymnanthemum, Hilliardiella, Oocephala, Orbivestus, Parapolydora, Polydora, Vernonella, Vernoniastrum, plus two genera that are named as new: Namibithamnus and Pseudopegolettia. Twelve new combinations are provided and two species, Vernonia potamiphila and Vernonia collinii Klatt., hom. illeg., remain unplaced because of a lack of material. Pollen types are illustrated including previously recognized types: non-lophate, sublophate, tricolporate lophate, and non-colpate triporate lophate. A type previously unknown in the Asteraceae is described here and in a separate paper for Oocephala and Polydora; a non-colpate pantoporate lophate type with pores not strictly equatorial. PMID:27081344

  19. Vernonieae (Asteraceae) of southern Africa: A generic disposition of the species and a study of their pollen.

    PubMed

    Robinson, Harold; Skvarla, John J; Funk, Vicki A

    2016-01-01

    Current and previously included members of the Tribe Vernonieae (Asteraceae) of southern Africa are listed in their presently recognized genera with complete synonymies and keys to genera and species. The genus Vernonia, as presently delimited, does not occur in Africa. Genera of the Vernonieae presently recognized from southern Africa are Baccharoides, Bothriocline, Cyanthillium, Distephanus, Erlangea, Ethulia, Gymnanthemum, Hilliardiella, Oocephala, Orbivestus, Parapolydora, Polydora, Vernonella, Vernoniastrum, plus two genera that are named as new: Namibithamnus and Pseudopegolettia. Twelve new combinations are provided and two species, Vernonia potamiphila and Vernonia collinii Klatt., hom. illeg., remain unplaced because of a lack of material. Pollen types are illustrated including previously recognized types: non-lophate, sublophate, tricolporate lophate, and non-colpate triporate lophate. A type previously unknown in the Asteraceae is described here and in a separate paper for Oocephala and Polydora; a non-colpate pantoporate lophate type with pores not strictly equatorial. PMID:27081344

  20. Sustained High HIV Incidence in Young Women in Southern Africa: Social, Behavioral and Structural Factors and Emerging Intervention Approaches

    PubMed Central

    Harrison, Abigail; Colvin, Christopher J.; Kuo, Caroline; Swartz, Alison; Lurie, Mark

    2015-01-01

    Young women in southern Africa experience some of the highest incidence rates of HIV infection in the world. Across southern Africa, HIV prevalence among women increases rapidly between the teenage years and young adulthood. Adult HIV prevalence is 16.8 percent in South Africa, 23 percent in Botswana, 23 percent in Lesotho and 26.5 percent in Swaziland. Existing research has illuminated some of the key social, behavioral and structural factors associated with young women's disproportionate HIV risk, including gendered social norms that advantage male power in sexual relationships, and age disparities in relationships between younger women and older male partners. Important structural factors include the region's history of labor migration and legacy of family disruption, and entrenched social and economic inequalities. New interventions are emerging to address these high levels of HIV risk in the key population of young women, including structural interventions, biomedical prevention such as PrEP, and combined HIV prevention approaches. PMID:25855338

  1. Shear velocity and anisotropy distributions beneath southern Africa's cratons: Lithospheric structure, deformation, LAB and other discontinuities

    NASA Astrophysics Data System (ADS)

    Adam, Joanne; Lebedev, Sergei

    2013-04-01

    Seismic-velocity structure and anisotropy of cratonic lithosphere offer important clues on the enigmatic formation and stabilization of cratons. Broad-band surface waves are highly sensitive to both the isotropic-average shear speeds from the upper crust down to the asthenosphere (characterising the composition and thermal state of the lithosphere) and to radial and azimuthal shear-wave anisotropy (indicative of ancient and recent deformation and flow). Recently, receiver function studies have yielded exciting but puzzling new evidence, revealing multiple discontinuities at different depths within the lithosphere-asthenosphere depth range beneath cratons. While some of the receiver-function signals probably indicate the lithosphere-asthenosphere boundary (LAB), others must be due to sharp radial changes in the mantle-rock composition or anisotropy. We have recently used teleseismic interferometry to measure thousands of inter-station, Rayleigh- and Love-wave, phase-velocity curves across southern Africa (Adam and Lebedev 2012). Here, we invert the very-broadband dispersion data for the profiles of the shear speed and azimuthal and radial anisotropy beneath different parts of the Kaapvaal Craton and the Limpopo Belt. Systematic model space mapping is used to evaluate parameter trade-offs and to ensure the robustness of the anisotropy profiles. Our results, firstly, reconcile the long-debated previous models based on different interpretations of SKS-splitting measurements in southern Africa (one end-member model placing anisotropy primarily into the lithosphere and attributing it to Archean deformation and the other placing it into the asthenosphere, with recently developed fabric). We show that the depth distribution of anisotropy comprises elements of both models: anisotropy in the asthenosphere shows fast-propagation directions parallel to the plate motion; anisotropy in the Limpopo and northern Kaapvaal lithosphere shows fast directions parallel to the Archean

  2. Slope Deposits and (Paleo)Soils as Geoarchives to Reconstruct Late Quaternary Environments of Southern Africa

    NASA Astrophysics Data System (ADS)

    Huerkamp, K.; Voelkel, J.; Heine, K.; Bens, O.

    2009-04-01

    Although it is clear that large, rapid temperature changes have occurred during the last glacial-interglacial cycle and the Holocene in southern Africa, we have only limited, and often imprecise, knowledge of how the major moisture-bearing atmospheric circulation systems have reacted to these changes. Using slope deposits and soils as palaeoclimatic geoarchives we will overcome these constraints. The role of many geoarchives in the reconstruction of the Quaternary climate in southern Africa remains controversial, since the paleoclimate data are based on evidence from marine cores, lake sediments, speleothems and spring sinter, fluvial sediments, aeolian sands and dust, colluvium, and coastal sediments. To elucidate climate controls on Quaternary landscape evolution and to use these data for palaeoclimatic reconstructions, thus far slope deposits and soils have been investigated. Climatic controls on these cycles are incompletely known. The availability of results from earlier fieldwork, micromorphology, Optical Stimulated Luminescence (OSL), 14C dating and stable carbon isotope analysis will permit a thorough assessment of slope deposits and soils in terms of their palaeoenvironmental potential. The knowledge of suitable areas and sites in different climatic zones of southern Africa where slope deposits and soils have already been found document the late Quaternary climatic history and even climatic anomalies (e.g. Younger Dryas period at Eksteenfontein, 8.2 ka event at Tsumkwe, 4 ka event in the Auob valley, Little Ice Age in the Namib Desert). The findings will show the late Quaternary history of precipitation fluctuations, of the shifting of the ITCZ (and the ABF - Agulhas-Benguela Front), of wind intensities and directions, and of extreme precipitation events. The project will employ state-of-the-art geoscience methodology to interpret the record of precipitation changes of the late Quaternary, including the shifting of the summer and winter rain belts, the

  3. Late Holocene Climatic Changes in Western Equatorial Africa Inferred from Pollen from Lake Sinnda, Southern Congo

    NASA Astrophysics Data System (ADS)

    Vincens, Annie; Schwartz, Dominique; Bertaux, Jacques; Elenga, Hilaire; de Namur, Christian

    1998-07-01

    Pollen analysis of two cores from the Lake Sinnda, located in one of the driest areas of the southern Congo, reveals a history of vegetation and climate in this region during the past 5000 yr. A major change centered around 3000-2500 yr B.P. is indicated by an abrupt decrease in forest pollen and by a corresponding increase in grassland pollen. Concurrent drying up of the lake shows that climate, in particular aridity, was the major cause of this change. This paleoclimatic reconstruction conforms with evidence for drier conditions in other parts of western equatorial Africa, such as the development of isolated enclosed savannas and of heliophilous forested formations. The aridity is recorded more fully at Lake Sinnda than at the previous studied ones. It probably lasted longer, from 4200 to 1300 yr B.P., and was more progressive than previously inferred. The aridity predates agriculture marked by pollen of the oil palm at Lake Sinnda.

  4. Central southern Africa at the time of the African Humid Period: a new analysis of Holocene palaeoenvironmental and palaeoclimate data

    NASA Astrophysics Data System (ADS)

    Burrough, S. L.; Thomas, D. S. G.

    2013-11-01

    The Holocene African Humid Period (c 14.8-5.5 ka) is now recognised in high-resolution records from western Africa as well as in tropical Africa north of the equator. Establishing a clear picture of Late Quaternary, including Holocene, environmental changes in central southern Africa is proving both difficult and contentious. This is because in dryland systems in particular it can be difficult to distinguish the effects of sub-millennial scale regional climatic variability from those of major externally-forced global climate changes, and because it is essential to distinguish records of environmental drivers from those of environmental responses. We analyse and review existing records for central southern Africa, and neighbouring areas affected by the same climate systems, to understand the primary controls of regional hydrological systems during the Holocene. We then present new data from Makgadikgadi basin barchan dunes that indicate mid-late Holocene aridity following a period of marked hydrological dynamism extending from the early Holocene. We suggest that present-day conditions in central southern Africa are relatively stable compared to the early and mid-Holocene and infer that this period of relative stability in the landscape has occurred since ca 2 ka. We explain Holocene hydrological changes through analysis of changing zonal climatic influences linked to Congo Air Boundary (CAB) and Intertropical Convergence Zone (ITCZ) dynamics, the effects of which filter into the region via complex drainage basin dynamics. It is proposed that, sensu stricto, the AHP was not a spatially uniform feature of early Holocene central southern Africa.

  5. Regulating the for-profit private health sector: lessons from East and Southern Africa.

    PubMed

    Doherty, Jane E

    2015-03-01

    International evidence shows that, if poorly regulated, the private health sector may lead to distortions in the type, quantity, distribution, quality and price of health services, as well as anti-competitive behaviour. This article provides an overview of legislation governing the for-profit private health sector in East and Southern Africa. It identifies major implementation problems and suggests strategies Ministries of Health could adopt to regulate the private sector more effectively and in line with key public health objectives. This qualitative study was based on a document review of existing legislation in the region, and seven semi-structured interviews with individuals selected purposively on the basis of their experience in policymaking and legislation. Legislation was categorized according to its objectives and the level at which it operates. A thematic content analysis was conducted on interview transcripts. Most legislation focuses on controlling the entry of health professionals and organizations into the market. Most countries have not developed adequate legislation around behaviour following entry. Generally the type and quality of services provided by private practitioners and facilities are not well-regulated or monitored. Even where there is specific health insurance regulation, provisions seldom address open enrolment, community rating and comprehensive benefit packages (except in South Africa). There is minimal control of prices. Several countries are updating and improving legislation although, in most cases, this is without the benefit of an overarching policy on the private sector, or reference to wider public health objectives. Policymakers in the East and Southern African region need to embark on a programme of action to strengthen regulatory frameworks and instruments in relation to private health care provision and insurance. They should not underestimate the power of the private health sector to undermine efforts for increased

  6. Resourcing resilience: social protection for HIV prevention amongst children and adolescents in Eastern and Southern Africa.

    PubMed

    Toska, Elona; Gittings, Lesley; Hodes, Rebecca; Cluver, Lucie D; Govender, Kaymarlin; Chademana, K Emma; Gutiérrez, Vincent Evans

    2016-07-01

    Adolescents are the only age group with growing AIDS-related morbidity and mortality in Eastern and Southern Africa, making HIV prevention research among this population an urgent priority. Structural deprivations are key drivers of adolescent HIV infection in this region. Biomedical interventions must be combined with behavioural and social interventions to alleviate the socio-structural determinants of HIV infection. There is growing evidence that social protection has the potential to reduce the risk of HIV infection among children and adolescents. This research combined expert consultations with a rigorous review of academic and policy literature on the effectiveness of social protection for HIV prevention among children and adolescents, including prevention for those already HIV-positive. The study had three goals: (i) assess the evidence on the effectiveness of social protection for HIV prevention, (ii) consider key challenges to implementing social protection programmes that promote HIV prevention, and (iii) identify critical research gaps in social protection and HIV prevention, in Eastern and Southern Africa. Causal pathways of inequality, poverty, gender and HIV risk require flexible and responsive social protection mechanisms. Results confirmed that HIV-inclusive child-and adolescent-sensitive social protection has the potential to interrupt risk pathways to HIV infection and foster resilience. In particular, empirical evidence (literature and expert feedback) detailed the effectiveness of combination social protection particularly cash/in-kind components combined with "care" and "capability" among children and adolescents. Social protection programmes should be dynamic and flexible, and consider age, gender, HIV-related stigma, and context, including cultural norms, which offer opportunities to improve programmatic coverage, reach and uptake. Effective HIV prevention also requires integrated social protection policies, developed through strong national

  7. Estimating probabilistic rainfall and food security outcomes for eastern and southern Africa

    NASA Astrophysics Data System (ADS)

    Verdin, J.; Funk, C.; Dettinger, M.; Brown, M.

    2009-05-01

    Since 1980, the number of undernourished people in eastern and southern Africa has more than doubled. Rural development stalled and rural poverty expanded during the 1990s. Population growth remains high, and declining per-capita agricultural capacity retards development. In September of 2008, Ethiopia, Kenya, Djibouti, and Somalia faced high or extreme conditions of food insecurity caused by repeated droughts and rapid food price inflation. In this talk we present research, performed for the US Agency for International Development on probabilistic projections of rainfall and food security trends for eastern and southern Africa. Analyses of station data and satellite-based estimates of precipitation have identified another problematic trend: main growing- season rainfall has diminished by ~15% in food-insecure countries clustered along the western rim of the Indian Ocean. Occurring during the main growing seasons in poor countries dependent on rain-fed agriculture, these declines constitute a long term danger to subsistence agricultural and pastoral livelihoods. Tracing moisture deficits upstream to an anthropogenically-induced warming Indian Ocean leads us to conclude that further rainfall declines are likely. We present analyses suggesting that warming in the central Indian Ocean disrupts onshore moisture transports, reducing continental rainfall. Thus, late 20th century Indian Ocean warming has probably already produced societally dangerous climate change by creating drought and social disruption in some of the world's most fragile food economies. We quantify the potential impacts of the observed precipitation and agricultural capacity trends by modeling millions of undernourished people as a function of rainfall, population, cultivated area, and seed and fertilizer use. Persistence of current trends may result in a 50% increase in undernourished people. On the other hand, modest increases in per-capita agricultural productivity could more than offset the

  8. Impacts of climate change on water resources in southern Africa: A review

    NASA Astrophysics Data System (ADS)

    Kusangaya, Samuel; Warburton, Michele L.; Archer van Garderen, Emma; Jewitt, Graham P. W.

    The Intergovernmental Panel on Climate Change concluded that there is consensus that the increase of atmospheric greenhouse gases will result in climate change which will cause the sea level to rise, increased frequency of extreme climatic events including intense storms, heavy rainfall events and droughts. This will increase the frequency of climate-related hazards, causing loss of life, social disruption and economic hardships. There is less consensus on the magnitude of change of climatic variables, but several studies have shown that climate change will impact on the availability and demand for water resources. In southern Africa, climate change is likely to affect nearly every aspect of human well-being, from agricultural productivity and energy use to flood control, municipal and industrial water supply to wildlife management, since the region is characterised by highly spatial and temporally variable rainfall and, in some cases, scarce water resources. Vulnerability is exacerbated by the region's low adaptive capacity, widespread poverty and low technology uptake. This paper reviews the potential impacts of climate change on water resources in southern Africa. The outcomes of this review include highlighting studies on detected climate changes particularly focusing on temperature and rainfall. Additionally, the impacts of climate change are highlighted, and respective studies on hydrological responses to climate change are examined. The review also discusses the challenges in climate change impact analysis, which inevitably represents existing research and knowledge gaps. Finally the paper concludes by outlining possible research areas in the realm of climate change impacts on water resources, particularly knowledge gaps in uncertainty analysis for both climate change and hydrological modelling.

  9. Lithospheric mantle evolution monitored by overlapping large igneous provinces: Case study in southern Africa

    NASA Astrophysics Data System (ADS)

    Jourdan, F.; Bertrand, H.; Féraud, G.; Le Gall, B.; Watkeys, M. K.

    2009-02-01

    Most of the studies on the large igneous provinces (LIPs) focus on Phanerozoic times, and in particular, those related to the disruption of Pangea (e.g. CAMP, Karoo, Parana-Etendeka) while Precambrian LIPs (e.g. Ventersdorpf, Fortescue) remain less studied. Although the investigation of Precambrian LIPs is difficult because they are relatively poorly preserved, assessment of their geochemical characteristics in parallel with younger overlapping LIP is fundamental for monitoring the evolution of the mantle composition through time. Recent 40Ar/ 39Ar dating of the Okavango giant dyke swarm (and related sills) in southern Africa showed that ~ 90% of the dykes were emplaced at 179 ± 1 Ma and belong to the Karoo large igneous province whereas ~ 10% of dykes yielded Proterozoic ages (~ 1-1.1 Ga). Here, we provide new major, trace and rare earth elements analyses of the low-Ti Proterozoic Okavango dyke swarm (PODS) that suggest, combined with age data, a cognate origin with the 1.1 Ga Umkondo large igneous province (UIP), southern Africa. The geochemical characteristics of the PODS and UIP basalts are comparable to those of overlapping low-Ti Karoo basalts, and suggest that both LIPs were derived from similar enriched mantle sources. A mantle plume origin for these LIPs is not easily reconciled with the geochemical dataset and the coincidence of two compositionally similar mantle plumes acting 900 Myr apart is unlikely. Instead, we propose that the Umkondo and Karoo large igneous provinces monitored the slight evolution of a shallow enriched lithospheric mantle from Proterozoic to Jurassic.

  10. Improved predictability of droughts over southern Africa using the standardized precipitation evapotranspiration index and ENSO

    NASA Astrophysics Data System (ADS)

    Manatsa, Desmond; Mushore, Terrence; Lenouo, Andre

    2015-09-01

    The provision of timely and reliable climate information on which to base management decisions remains a critical component in drought planning for southern Africa. In this observational study, we have not only proposed a forecasting scheme which caters for timeliness and reliability but improved relevance of the climate information by using a novel drought index called the standardised precipitation evapotranspiration index (SPEI), instead of the traditional precipitation only based index, the standardised precipitation index (SPI). The SPEI which includes temperature and other climatic factors in its construction has a more robust connection to ENSO than the SPI. Consequently, the developed ENSO-SPEI prediction scheme can provide quantitative information about the spatial extent and severity of predicted drought conditions in a way that reflects more closely the level of risk in the global warming context of the sub region. However, it is established that the ENSO significant regional impact is restricted only to the period December-March, implying a revisit to the traditional ENSO-based forecast scheme which essentially divides the rainfall season into the two periods, October to December and January to March. Although the prediction of ENSO events has increased with the refinement of numerical models, this work has demonstrated that the prediction of drought impacts related to ENSO is also a reality based only on observations. A large temporal lag is observed between the development of ENSO phenomena (typically in May of the previous year) and the identification of regional SPEI defined drought conditions. It has been shown that using the Southern Africa Regional Climate Outlook Forum's (SARCOF) traditional 3-month averaged Nino 3.4 SST index (June to August) as a predictor does not have an added advantage over using only the May SST index values. In this regard, the extended lead time and improved skill demonstrated in this study could immensely benefit

  11. Integrated Water Resources Management: Relevant concept or irrelevant buzzword? A capacity building and research agenda for Southern Africa

    NASA Astrophysics Data System (ADS)

    van der Zaag, Pieter

    This article examines the concept ‘Integrated Water Resources Management’ (IWRM) and inquires as to its relevance for the Southern African region. The paper first acknowledges the contributions made to IWRM by three regional initiatives-WaterNet, the Water Research Fund for Southern Africa (WARFSA), and the Southern African chapter of the Global Water Partnership. Then, three important aspects of IWRM are highlighted: that IWRM requires institutional capacity to integrate, which often is a scarce resource; that IWRM is neither solution nor recipe, but rather a perspective or way of looking at problems with a view to solving them through transparent and inclusive decision-making processes; and that IWRM should explicitly deal with the fact that water tends to build asymmetrical relationships between people, communities and nations. An IWRM agenda is subsequently set out, focussing on five critical issues: the dilemma between economic development and sustainability; the unresolved issue of water as an economic good; the place and role of rainfed farmers in IWRM; the importance of training and teaching; and the need for building reflexive capacity in the new and existing water institutions. The paper concludes that IWRM is a relevant, yet elusive and fuzzy concept. Evidence from Southern Africa and around the world shows that IWRM inspires a new generation of water managers and researchers to act creatively; assists in addressing the Millennium Development Goals (MDGs); and instils mutual respect, understanding and co-operation among water professionals in Southern Africa.

  12. Transitioning HIV care and treatment programs in southern Africa to full local management.

    PubMed

    Vermund, Sten H; Sidat, Mohsin; Weil, Lori F; Tique, José A; Moon, Troy D; Ciampa, Philip J

    2012-06-19

    Global AIDS programs such as the US President's Emergency Plan for AIDS Relief (PEPFAR) face a challenging health care management transition. HIV care must evolve from vertically-organized, externally-supported efforts to sustainable, locally controlled components that are integrated into the horizontal primary health care systems of host nations. We compared four southern African nations in AIDS care, financial, literacy, and health worker capacity parameters (2005 to 2009) to contrast in their capacities to absorb the huge HIV care and prevention endeavors that are now managed with international technical and fiscal support. Botswana has a relatively high national income, a small population, and an advanced HIV/AIDS care program; it is well poised to take on management of its HIV/AIDS programs. South Africa has had a slower start, given HIV denialism philosophies of the previous government leadership. Nonetheless, South Africa has the national income, health care management, and health worker capacity to succeed in fully local management. The sheer magnitude of the burden is daunting, however, and South Africa will need continuing fiscal assistance. In contrast, Zambia and Mozambique have comparatively lower per capita incomes, many fewer health care workers per capita, and lower national literacy rates. It is improbable that fully independent management of their HIV programs is feasible on the timetable being contemplated by donors, nor is locally sustainable financing conceivable at present. A tailored nation-by-nation approach is needed for the transition to full local capacitation; donor nation policymakers must ensure that global resources and technical support are not removed prematurely. PMID:22706012

  13. Pleistocene sea-level fluctuations and human evolution on the southern coastal plain of South Africa

    NASA Astrophysics Data System (ADS)

    Compton, John S.

    2011-03-01

    Humans evolved in Africa, but where and how remain unclear. Here it is proposed that the southern coastal plain (SCP) of South Africa may have served as a geographical point of origin through periodic expansion and contraction (isolation) in response to glacial/interglacial changes in sea level and climate. During Pleistocene interglacial highstands when sea level was above -75 m human populations were isolated for periods of 360-3400 25-yr generations on the SCP by the rugged mountains of the Cape Fold Belt, climate and vegetation barriers. The SCP expands five-fold as sea level falls from -75 to -120 m during glacial maxima to form a continuous, unobstructed coastal plain accessible to the interior. An expanded and wet glacial SCP may have served as a refuge to humans and large migratory herds and resulted in the mixing of previously isolated groups. The expansive glacial SCP habitat abruptly contracts, by as much as one-third in 300 yr, during the rapid rise in sea level associated with glacial terminations. Rapid flooding may have increased population density and competition on the SCP to select for humans who expanded their diet to include marine resources or hunted large animals. Successful adaptations developed on an isolated SCP are predicted to widely disperse during glacial terminations when the SCP rapidly contracts or during the initial opening of the SCP in the transition to glacial maxima. The hypothesis that periodic expansion and contraction of the SCP, as well as the coastal plain of North Africa, contributed to the stepwise origin of our species over the last 800 thousand years (kyr) is evaluated by comparing the archeological, DNA and sea-level records. These records generally support the hypothesis, but more complete and well dated records are required to resolve the extent to which sea-level fluctuations influenced the complex history of human evolution.

  14. Effects of Humidity on Aerosols in Southern Africa during the Biomass Burning Season

    NASA Technical Reports Server (NTRS)

    Magi, Brian I.; Hobbs, Peter V.

    2003-01-01

    Measurements of the aerosol total light scattering coefficient, asp, and the aerosol hemispheric backscatter ratio, p(1), as functions of relative humidity (RH in %) (so-called humidographs) at three wavelengths (450,550, and 700 nm) were obtained in the dry season in southern Africa (1) in ambient air in South Africa, Botswana, Mozambique and Zambia, (2) at various distances downwind in identifiable smoke plumes from biomass fires, and (3) along the southwest coast of Africa. The ratio of sigma(sub sp) at an RH of 80% to that at 30% provides a measure of the effects of RH on sigma(sub sp), and similarly for Beta(1). For the three broad sampling categories given above, and at a wavelength of 550 nm, these ratios varied from 1.42 +/- 0.05 to 2.07 +/- 0.03 for sigma(sub sp), and from 0.69 +/- 0.05 to 0.99 +/- 0.14 for Beta(1). In general, humidographs for the ambient air samples showed a greater dependence on RH than those for smoke from identifiable biomass fires. During a period when dense, aged smoke was transported to the region from the north, the humidographs for sigma(sub sp) for ambient air samples were similar to those for identifiable smoke plume samples just approximately 10- to 50-min old. This suggests that as far as the effects of RH on sigma(sub sp) are concerned the effects of aging of smoke and its mixing with ambient air are realized within less than about an hour.

  15. Dental microwear of sympatric rodent species sampled across habitats in southern Africa: Implications for environmental influence.

    PubMed

    Burgman, Jenny H E; Leichliter, Jennifer; Avenant, Nico L; Ungar, Peter S

    2016-03-01

    Dental microwear textures have proven to be a valuable tool for reconstructing the diets of a wide assortment of fossil vertebrates. Nevertheless, some studies have recently questioned the efficacy of this approach, suggesting that aspects of habitat unrelated to food preference, especially environmental grit load, might have a confounding effect on microwear patterning that obscures the diet signal. Here we evaluate this hypothesis by examining microwear textures of 3 extant sympatric rodent species that vary in diet breadth and are found in a variety of habitat types: Mastomys coucha, Micaelamys namaquensis and Rhabdomys pumilio. We sample each of these species from 3 distinct environmental settings in southern Africa that differ in rainfall and vegetative cover: Nama-Karoo shrublands (semi-desert) and Dry Highveld grasslands in the Free State Province of South Africa, and Afromontane (wet) grasslands in the highlands of Lesotho. While differences between habitat types are evident for some of the species, inconsistency in the pattern suggests that the microwear signal is driven by variation in foods eaten rather than grit-level per se. It is clear that, at least for species and habitats sampled in the current study, environmental grit load does not swamp diet-related microwear signatures. PMID:26748948

  16. Oil and gas developments in central and southern Africa in 1987

    SciTech Connect

    Hartman, J.B.; Walker, T.L.

    1988-10-01

    Significant rightholding changes took place in central and southern Africa during 1987. Angola, Benin, Congo, Gabon, Ghana, Guinea, Guinea Bissau, Mauritania, Seychelles, Somali Republic, Tanzania, Zaire, and Zambia announced awards or acreage open for bidding. Decreases in exploratory rightholdings occurred in Cameroon, Congo, Cote d'Ivoire, Equatorial Guinea, Gabon, Kenya, Namibia, South Africa, and Tanzania. More wells and greater footage were drilled in 1987 than in 1986. Total wells increased by 18% as 254 wells were completed compared to 217 in 1986. Footage drilled during the year increased by 46% as about 1.9 million ft were drilled compared to about 1.3 million ft in 1986. The success rate for exploration wells in 1987 improved slightly to 36% compared to 34% in 1986. Significant discoveries were made in Nigeria, Angola, Congo, and Gabon. Seismic acquisition in 1987 was the major geophysical activity during the year. Total oil production in 1987 was 773 million bbl (about 2.1 million b/d), a decrease of 7%. The decrease is mostly due to a 14% drop in Nigerian production, which comprises 60% of total regional production. The production share of OPEC countries (Nigeria and Gabon) versus non-OPEC countries of 67% remained unchanged from 1986. 24 figs., 5 tabs.

  17. The evolutionary dynamics of canid and mongoose rabies virus in Southern Africa.

    PubMed

    Davis, P L; Rambaut, A; Bourhy, H; Holmes, E C

    2007-01-01

    Two variants of rabies virus (RABV) currently circulate in southern Africa: canid RABV, mainly associated with dogs, jackals, and bat-eared foxes, and mongoose RABV. To investigate the evolutionary dynamics of these variants, we performed coalescent-based analyses of the G-L inter-genic region, allowing for rate variation among viral lineages through the use of a relaxed molecular clock. This revealed that mongoose RABV is evolving more slowly than canid RABV, with mean evolutionary rates of 0.826 and 1.676 x 10(-3) nucleotide substitutions per site, per year, respectively. Additionally, mongoose RABV exhibits older genetic diversity than canid RABV, with common ancestors dating to 73 and 30 years, respectively, and while mongoose RABV has experienced exponential population growth over its evolutionary history in Africa, populations of canid RABV have maintained a constant size. Hence, despite circulating in the same geographic region, these two variants of RABV exhibit striking differences in evolutionary dynamics which are likely to reflect differences in their underlying ecology. PMID:17401615

  18. Rates of surface lowering and landscape development in southern South Africa: a cosmogenic view

    NASA Astrophysics Data System (ADS)

    Richardson, Janet; Vanacker, Veerle; Lang, Andreas; Hodgson, David

    2016-04-01

    The landscape of southern South Africa is characterised by large-scale erosion surfaces, including extensive pediments and multiple strath terraces, which document discordant river evolution through resistant quarzitic lithologies of the Cape Fold Belt (CFB). The timing and rate of erosion is poorly constrained. New cosmogenic ages from surfaces in South Africa are presented using in situ produced 10Be. Strath terraces in deeply incised rivers at two sites within the CFB indicate slow rates of erosion (1.54 - 11.79 m/Ma), which are some of the lowest rates recorded globally. Four pediment surfaces and a depth profile of the thickest pediment were also dated, and the results indicate that there are low rates of surface lowering on the pediments (0.44 - 1.24 m/Ma). The pediments are long-lived features (minimum exposure ages of 0.47 - 1.09 Ma), and are now deeply dissected. Given the minimum exposure ages, calculated river incision rates (42- 203 m/Ma) suggest that after a long period of geomorphic stability during pediment formation there was a discrete phase of increased geomorphic activity. The calculated minimum exposure ages are considered dubious because: 1) known rates of surrounding river incision (published and ours); 2) the climate conditions and time necessary for ferricrete formation on the pediment surfaces and; 3) the deeply incised catchments in the CFB on which the pediments sit, which all point to the pediments being much older. The pediments are fossilised remnants of a much larger geomorphic surface that formed after the main phase of exhumation in southern Africa. They form a store of sediment that currently sit above the surrounding rivers that have some of the lowest erosion rates in the world. These results indicate that steep topography can prevail even in areas of low erosion and tectonic quiescence, and that whilst cosmogenic dating of landscapes is an exciting development in earth sciences, care is needed especially in ancient settings. We

  19. Crustal structure of Nigeria and Southern Ghana, West Africa from P-wave receiver functions

    NASA Astrophysics Data System (ADS)

    Akpan, Ofonime; Nyblade, Andrew; Okereke, Chiedu; Oden, Michael; Emry, Erica; Julià, Jordi

    2016-04-01

    We report new estimates of crustal thickness (Moho depth), Poisson's ratio and shear-wave velocities for eleven broadband seismological stations in Nigeria and Ghana. Data used for this study came from teleseismic earthquakes recorded at epicentral distances between 30° and 95° and with moment magnitudes greater than or equal to 5.5. P-wave receiver functions were modeled using the Moho Ps arrival times, H-k stacking, and joint inversion of receiver functions and Rayleigh wave group velocities. The average crustal thickness of the stations in the Neoproterozoic basement complex of Nigeria is 36 km, and 23 km for the stations in the Cretaceous Benue Trough. The crustal structure of the Paleoproterozoic Birimian Terrain, and Neoproterozoic Dahomeyan Terrain and Togo Structural Unit in southern Ghana is similar, with an average Moho depth of 44 km. Poisson's ratios for all the stations range from 0.24 to 0.26, indicating a bulk felsic to intermediate crustal composition. The crustal structure of the basement complex in Nigeria is similar to the average crustal structure of Neoproterozoic terrains in other parts of Africa, but the two Neoproterozoic terrains in southern Ghana have a thicker crust with a thick mafic lower crust, ranging in thickness from 12 to 17 km. Both the thicker crust and thick mafic lower crustal section are consistent with many Precambrian suture zones, and thus we suggest that both features are relict from the collisional event during the formation of Gondwana.

  20. Seasonal cycle of convective spells over southern Africa during austral summer

    NASA Astrophysics Data System (ADS)

    Makarau, Amos; Jury, Mark R.

    1997-10-01

    The seasonal progression of summer wet spells over southern Africa is investigated. The November to March rainy season is modulated at the intraseasonal scale, with major wet spells every 20-30 days and internal evolution at higher frequencies. Corresponding circulation patterns for each wet spell illustrate the variable dynamics and physics as the season progresses. Early summer rainfall is associated with enhanced baroclinic westerly shear from the upper troposphere of the tropical Atlantic Ocean, whereas low-level moisture is advected from the central Indian Ocean. Extratropical westerly wave action is an important influence during early summer. As the summer season progresses, heating causes a retreat of the subtropical westerly jet stream. A quasi-stationary line of confluence along 20°S develops in the low levels during late summer, and extends from the Mozambique Channel to Angola. This trough is supported by an influx of moisture from the Congo and southern Mozambique Channel. Composite differences between early and late summer wet spells are evaluated numerically for the first time in this presentation.

  1. Increasing behavioral flexibility? New archaeological and ecological approaches to understanding the Howieson's Poort in Southern Africa

    NASA Astrophysics Data System (ADS)

    Kandel, A. W.; Bolus, M.; Bruch, A. A.; Haidle, M. N.; Hertler, C.; Märker, M.

    2012-04-01

    The Howieson's Poort (HP) of Southern Africa peaked between 60 and 65 ka and represents a distinct phase of cultural innovation adopted by modern humans during the Middle Stone Age. While researchers generally attribute the rise and fall of the HP to social and environmental causes, neither provides a complete explanation. As patterns at the site level come into focus, large-scale trends explaining the HP expansion remain uncertain. Comparisons with earlier and later cultural phases may provide ways to view the HP phenomenon. The most notable artifacts of the HP lithic industry are standardized, crescent-shaped, backed stone tools called segments that were mounted on wooden shafts in several orientations using mixtures of ground pigment and plant resin to create composite tools such as stone-tipped arrows and spears. The use of ocher, often faceted or striated from grinding and sometimes engraved with geometric patterns, attests to functional and possibly symbolic behavior. Other attributes of the HP include the use of laminar lithic technology to produce blades and a preference for finer grained raw materials. While rare bone tools hint at advanced hunting strategies, other organic finds include geometrically engraved and perforated ostrich eggshell containers and perhaps shell beads, artifacts that serve as markers conveying individual and group status. Analyses of faunal remains supports the possible use of snares and traps, in addition to diverse hunting strategies. Even the sediments testify to changes in behavior that involved the increasing maintenance of living areas. Micromorphological evidence for the construction of bedding layers that were regularly cleaned by burning appears towards the end of the HP. While this combination of behaviors indicates a cultural complexity that did not exist before or after the HP, the reasons for its appearance and the causes of its demise remain unclear. To test the hypotheses of cultural and environmental causality and

  2. Distributions of trace gases and aerosols during the dry biomass burning season in southern Africa

    NASA Astrophysics Data System (ADS)

    Sinha, Parikhit; Hobbs, Peter V.; Yokelson, Robert J.; Blake, Donald R.; Gao, Song; Kirchstetter, Thomas W.

    2003-09-01

    Vertical profiles in the lower troposphere of temperature, relative humidity, sulfur dioxide (SO2), ozone (O3), condensation nuclei (CN), and carbon monoxide (CO), and horizontal distributions of twenty gaseous and particulate species, are presented for five regions of southern Africa during the dry biomass burning season of 2000. The regions are the semiarid savannas of northeast South Africa and northern Botswana, the savanna-forest mosaic of coastal Mozambique, the humid savanna of southern Zambia, and the desert of western Namibia. The highest average concentrations of carbon dioxide (CO2), CO, methane (CH4), O3, black particulate carbon, and total particulate carbon were in the Botswana and Zambia sectors (388 and 392 ppmv, 369 and 453 ppbv, 1753 and 1758 ppbv, 79 and 88 ppbv, 2.6 and 5.5 μg m-3, and 13.2 and 14.3 μg m-3). This was due to intense biomass burning in Zambia and surrounding regions. The South Africa sector had the highest average concentrations of SO2, sulfate particles, and CN (5.1 ppbv, 8.3 μg m-3, and 6400 cm-3, respectively), which derived from biomass burning and electric generation plants and mining operations within this sector. Air quality in the Mozambique sector was similar to the neighboring South Africa sector. Over the arid Namibia sector there were polluted layers aloft, in which average SO2, O3, and CO mixing ratios (1.2 ppbv, 76 ppbv, and 310 ppbv, respectively) were similar to those measured over the other more polluted sectors. This was due to transport of biomass smoke from regions of widespread savanna burning in southern Angola. Average concentrations over all sectors of CO2 (386 ± 8 ppmv), CO (261 ± 81 ppbv), SO2 (2.5 ± 1.6 ppbv), O3 (64 ± 13 ppbv), black particulate carbon (2.3 ± 1.9 μg m-3), organic particulate carbon (6.2 ± 5.2 μg m-3), total particle mass (26.0 ± 4.7 μg m-3), and potassium particles (0.4 ± 0.1 μg m-3) were comparable to those in polluted, urban air. Since the majority of the measurements

  3. Aeolian dust emissions in Southern Africa: field measurements of dynamics and drivers

    NASA Astrophysics Data System (ADS)

    Wiggs, Giles; Thomas, David; Washington, Richard; King, James; Eckardt, Frank; Bryant, Robert; Nield, Joanna; Dansie, Andrew; Baddock, Matthew; Haustein, Karsten; Engelstaedter, Sebastian; von Holdt, Johannah; Hipondoka, Martin; Seely, Mary

    2016-04-01

    Airborne dust derived from the world's deserts is a critical component of Earth System behaviour, affecting atmospheric, oceanic, biological, and terrestrial processes as well as human health and activities. However, very few data have been collected on the factors that control dust emission from major source areas, or on the characteristics of the dust that is emitted. Such a paucity of data limits the ability of climate models to properly account for the radiative and dynamical impacts triggered by atmospheric dust. This paper presents field data from the DO4 Models (Dust Observations for Models) project that aims to understand the drivers of variability in dust emission processes from major source areas in southern Africa. Data are presented from three field campaigns undertaken between 2011 and 2015. We analysed remote sensing data to identify the key geomorphological units in southern Africa which are responsible for emission of atmospheric dust. These are the Makgadikgadi pans complex in northern Botswana, the ephemeral river valleys of western Namibia, and Etosha Pan in northern Namibia. Etosha Pan is widely recognised as perhaps the most significant source of atmospheric dust in the southern hemisphere. We deployed an array of field equipment within each source region to measure the variability in and dynamics of aeolian erosivity, as well as dust concentration and flux characteristics. This equipment included up to 11 meteorological stations measuring wind shear stress and other standard climatic parameters, Cimel sun photometers, a LiDAR, sediment transport detectors, high-frequency dust concentration monitors, and dust flux samplers. Further data were gathered at each site on the dynamics of surface characteristics and erodibility parameters that impact upon erosion thresholds. These data were augmented by use of a Pi-Swerl portable wind tunnel. Our data represent the first collected at source for these key dust emission areas and highlight the

  4. Geopotential field anomalies and regional tectonic features - two case studies: southern Africa and Germany

    NASA Astrophysics Data System (ADS)

    Korte, Monika; Mandea, Mioara

    2016-05-01

    Maps of magnetic and gravity field anomalies provide information about physical properties of the Earth's crust and upper mantle, helpful in understanding geological conditions and tectonic structures. Depending on data availability, whether from the ground, airborne, or from satellites, potential field anomaly maps contain information on different ranges of spatial wavelengths, roughly corresponding to sources at different depths. Focussing on magnetic data, we compare amplitudes and characteristics of anomalies from maps based on various available data and as measured at geomagnetic repeat stations. Two cases are investigated: southern Africa, characterized by geologically old cratons and strong magnetic anomalies, and the smaller region of Germany with much younger crust and weaker anomalies. Estimating lithospheric magnetic anomaly values from the ground stations' time series (repeat station crustal biases) reveals magnetospheric field contributions causing time-varying offsets of several nT in the results. Similar influences might be one source of discrepancy when merging anomaly maps from different epochs. Moreover, we take advantage of recently developed satellite potential field models and compare magnetic and gravity gradient anomalies of ˜ 200 km resolution. Density and magnetization represent independent rock properties and thus provide complementary information on compositional and structural changes. Comparing short- and long-wavelength anomalies and the correlation of rather large-scale magnetic and gravity anomalies, and relating them to known lithospheric structures, we generally find a better agreement in the southern African region than the German region. This probably indicates stronger concordance between near-surface (down to at most a few km) and deeper (several kilometres down to Curie depth) structures in the former area, which can be seen to agree with a thicker lithosphere and a lower heat flux reported in the literature for the southern

  5. Regional climate change projections over southern Africa: Benefits of a high resolution climate change simulation

    NASA Astrophysics Data System (ADS)

    Haensler, A.; Hagemann, S.; Jacob, D.

    2009-12-01

    The southern African region is known to be a biodiversity hotspot but future climate change is likely to have a major influence on the biodiversity. To estimate the impacts of climate change on the biosphere high resolution climate information is needed for both current and future conditions. In the framework of the BIOTA South project we are therefore applying the regional climate model (RCM) REMO of the Max-Planck-Institute for Meteorology (MPI-M) over the southern African region. The model is integrated for a transient climate change simulation for the time period 1960 to 2100 at 1/2 degree and 1/6 degree horizontal resolution using a double-nesting approach. The 1/6 degree simulation is the first long-term climate projection for southern Africa on such a high horizontal resolution. The boundary forcing for the 1/2 degree projection is taken from a global ECHAM5/MPIOM IPCC A1B scenario simulation. In the current study we will analyse projected changes on the hydrological cycle, thereby focusing on the Orange river catchment and on the main BIOTA research transect, which spans from the north-east corner of Namibia to the Cape region in the South. In order to quantify the impact of model resolution on the projected changes we will intercompare the two REMO simulations and the ECHAM5/MPIOM forcing data. A comparison for the high resolution REMO validation simulation and its forcing ERA40 data already revealed an added value in the representation of the seasonal rainfall characteristics for the region. The benefits of using high resolution RCM data for climate change studies will be highlighted and uncertainties introduced by the application of an RCM will be discussed.

  6. Upper Mantle Seismic Structure Beneath Southern Africa: Constraints on the Buoyancy Supporting the African Superswell

    NASA Astrophysics Data System (ADS)

    Brandt, Martin B. C.; Grand, Stephen P.; Nyblade, Andrew A.; Dirks, Paul H. G. M.

    2012-04-01

    We present new one-dimensional SH-wave velocity models of the upper mantle beneath the Kalahari craton in southern Africa obtained from waveform inversion of regional seismograms from an Mw = 5.9 earthquake located near Lake Tanganyika recorded on broadband seismic stations deployed during the 1997-1999 Southern African Seismic Experiment. The velocity in the lithosphere beneath the Kalahari craton is similar to that of other shields, and there is little evidence for a significant low velocity zone beneath the lithosphere. The lower part of the lithosphere, from 110 to 220 km depth, is slightly slower than beneath other shields, possibly due to higher temperatures or a decrease in Mg number (Mg#). If the slower velocities are caused by a thermal anomaly, then slightly less than half of the unusually high elevation of the Kalahari craton can be explained by shallow buoyancy from a hot lithosphere. However, a decrease in the Mg# of the lower lithosphere would increase the density and counteract the buoyancy effect of the higher temperatures. We obtain a thickness of 250 ± 30 km for the mantle transition zone, which is similar to the global average, but the velocity gradient between the 410 and 660 km discontinuities is less steep than in global models, such as PREM and IASP91. We also obtain velocity jumps of between 0.16 ± 0.1 and 0.21 ± 0.1 km/s across the 410 km discontinuity. Our results suggest that there may be a thermal or chemical anomaly in the mantle transition zone, or alternatively that the shear wave velocity structure of the transition zone in global reference models needs to be refined. Overall, our seismic models provide little support for an upper mantle source of buoyancy for the unusually high elevation of the Kalahari craton, and hence the southern African portion of the African Superswell.

  7. Azimuthal anisotropy beneath southern Africa from very broad-band surface-wave dispersion measurements

    NASA Astrophysics Data System (ADS)

    Adam, Joanne M.-C.; Lebedev, Sergei

    2012-10-01

    Seismic anisotropy within the lithosphere of cratons preserves an important record of their ancient assembly. In southern Africa, anisotropy across the Archean Kaapvaal Craton and Limpopo Belt has been detected previously by observations of SKS-wave splitting. Because SKS-splitting measurements lack vertical resolution, however, the depth distribution of anisotropy has remained uncertain. End-member interpretations invoked the dominance of either anisotropy in the lithosphere (due to the fabric formed by deformation in Archean or Palaeoproterozoic orogenies) or that in the asthenosphere (due to the fabric formed by the recent plate motion), each with significant geodynamic implications. To determine the distribution of anisotropy with depth, we measured phase velocities of seismic surface waves between stations of the Southern African Seismic Experiment. We applied two complementary measurement approaches, very broad-band cross-correlation and multimode waveform inversion. Robust, Rayleigh- and Love-wave dispersion curves were derived for four different subregions of the Archean southern Africa in a period range from 5 s to 250-400 s (Rayleigh) and 5 s to 100-250 s (Love), depending on the region. Rayleigh-wave anisotropy was determined in each region at periods from 5 s to 150-200 s, sampling from the upper crust down to the asthenosphere. The jackknife method was used to estimate uncertainties, and the F-test to verify the statistical significance of anisotropy. We detected strong anisotropy with a N-S fast-propagation azimuth in the upper crust of the Limpopo Belt. We attribute it to aligned cracks, formed by the regional, E-W extensional stress associated with the southward propagation of the East African Rift. Our results show that it is possible to estimate regional stress from short-period, surface wave anisotropy, measured in this study using broad-band array recordings of teleseismic surface waves. Rayleigh-wave anisotropy at 70-120 s periods shows that

  8. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals

    PubMed Central

    Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable. PMID:26125972

  9. Mathematical Modeling to Assess the Drivers of the Recent Emergence of Typhoid Fever in Blantyre, Malawi

    PubMed Central

    Pitzer, Virginia E.; Feasey, Nicholas A.; Msefula, Chisomo; Mallewa, Jane; Kennedy, Neil; Dube, Queen; Denis, Brigitte; Gordon, Melita A.; Heyderman, Robert S.

    2015-01-01

    Background. Multiyear epidemics of Salmonella enterica serovar Typhi have been reported from countries across eastern and southern Africa in recent years. In Blantyre, Malawi, a dramatic increase in typhoid fever cases has recently occurred, and may be linked to the emergence of the H58 haplotype. Strains belonging to the H58 haplotype often exhibit multidrug resistance and may have a fitness advantage relative to other Salmonella Typhi strains. Methods. To explore hypotheses for the increased number of typhoid fever cases in Blantyre, we fit a mathematical model to culture-confirmed cases of Salmonella enterica infections at Queen Elizabeth Central Hospital, Blantyre. We explored 4 hypotheses: (1) an increase in the basic reproductive number (R0) in response to increasing population density; (2) a decrease in the incidence of cross-immunizing infection with Salmonella Enteritidis; (3) an increase in the duration of infectiousness due to failure to respond to first-line antibiotics; and (4) an increase in the transmission rate following the emergence of the H58 haplotype. Results. Increasing population density or decreasing cross-immunity could not fully explain the observed pattern of typhoid emergence in Blantyre, whereas models allowing for an increase in the duration of infectiousness and/or the transmission rate of typhoid following the emergence of the H58 haplotype provided a good fit to the data. Conclusions. Our results suggest that an increase in the transmissibility of typhoid due to the emergence of drug resistance associated with the H58 haplotype may help to explain recent outbreaks of typhoid in Malawi and similar settings in Africa. PMID:26449939

  10. Rayleigh wave group velocity dispersion across Northern Africa, Southern Europe and the Middle East

    SciTech Connect

    McNamara, D.E.; Walter, W.R.

    1997-07-15

    THis report presents preliminary results from a large scale study of surface wave group velocity dispersion throughout Northern Africa, the Mediterranean, Southern Europe and the Middle East. Our goal is to better define the 3D lithospheric shear-wave velocity structure within this region by improving the resolution of global surface wave tomographic studies. We hope to accomplish this goal by incorporating regional data at relatively short periods (less than 40 sec), into the regionalization of lateral velocity variation. Due to the sparse distributions of stations and earthquakes throughout the region (Figure 1) we have relied on data recorded at both teleseismic and regions; distances. Also, to date we have concentrated on Rayleigh wave group velocity measurements since valuable measurements can be made without knowledge of the source. In order to obtain Rayleigh wave group velocity throughout the region, vertical component teleseismic and regional seismograms were gathered from broadband, 3-component, digital MEDNET, GEOSCOPE and IRIS stations plus the portable PASSCAL deployment in Saudi Arabia. Figure 1 shows the distribution of earthquakes (black circles) and broadband digital seismic stations (white triangles) throughout southern Europe, the middle east and northern Africa used in this study. The most seismicly active regions of northern Africa are the Atlas mountains of Morocco and Algeria as well as the Red Sea region to the east. Significant seismicity also occurs in the Mediterranean, southern Europe and throughout the high mountains and plateaus of the middle-east. To date, over 1300 seismograms have been analyzed to determine the individual group velocities of 10-150 second Rayleigh waves. Travel times, for each period, are then inverted in a back projection tomographic method in order to determine the lateral group velocity variation throughout the region. These results are preliminary, however, Rayleigh wave group velocity maps for a range of

  11. Attributing the Risk of Late Onset of the Rainy Season in Southern Africa to Climate Change

    NASA Astrophysics Data System (ADS)

    Wolski, P.; Stone, D. A.; Tadross, M. A.; Hewitson, B.; Wehner, M. F.

    2015-12-01

    Rainfed subsistence agriculture in Sub-Saharan Africa accounts for approximately 96% of all cropland. This, combined with strong intra-seasonal and interannual variability of rains makes food production sensitive to climate variations, and increases the potential and frequent occurrence of climate-triggered famines. Farmers often identify the timing of the onset of the growing season (in many areas dependent predominantly on rainfall) as a key climate characteristic which influences crop yields, influences planting activities, and can be used to adapt to changing seasonal conditions without requiring additional resources. It is thus important to understand factors affecting the timing of the onset of rains, particularly how anthropogenic climate change may increase the risk of later onsets. Here, we present a study designed to assess the level of influence of anthropogenic CO2 emissions on the risk of late onset in southern Africa. Considering numerous definitions of rainy season onset, we use one that describes onset related to the growing of maize, as it is the most wide-ranging and consumed staple in the region. Attribution is done using a risk-based event attribution methodology in which we use dedicated simulations by AGCMs (HadAM3p-N96 and CAM5.1-1degree) performed in the framework of the Climate of the 20th Century Plus (C20C+) Detection and Attribution Project. These simulations enable comparison of event (in our case the timing of the onset of a particular rainy season) probabilities under real world climates with those under a climate that might have been had human activities not emitted greenhouse gases. The fraction of risk of later onsets, attributable to an increase in greenhouse gases, is done in a spatially-explicit way for onset events derived from observed and reanalysis data for the 2007-2014 period.

  12. Alien phytogeographic regions of southern Africa: numerical classification, possible drivers, and regional threats.

    PubMed

    Hugo, Sanet; Van Rensburg, Berndt J; Van Wyk, Abraham E; Steenkamp, Yolande

    2012-01-01

    The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management. PMID:22574145

  13. Spectral and geological interpretation of the lithospheric magnetic field over Southern Africa

    NASA Astrophysics Data System (ADS)

    Vervelidou, F.; Thebault, E.

    2011-12-01

    Measuring the Earth's lithospheric magnetic field is one of the non-destructive ways of gaining information about the bulk properties of the magnetic crust. This, in turn, should help us to infer hypothesis about the geometry and the depth of the causative sources. Unraveling these crustal structures calls for a combined use of all types of magnetic measurements from ground to space altitudes. In the framework of the !khure project, a joint program between South Africa and France, we recently produced a crustal field model at 30 km resolution using the Revised Spherical Cap Harmonic method. To achieve this high resolution, we combined ground, aeromagnetic and the latest CHAMP satellite data in a joint inversion. We estimated the set of parameters describing the crustal field in a robust way. In particular, a special effort was made during the pre-processing of the data to assess and then to improve the level of compatibility between the different data types. An inverse problem based on an iteratively re-weighted least squares and a bootstrap algorithm further provided us with a model having arguably realistic statistics. This important information will gain its full significance in the future of this work when converted into confidence intervals for the magnetization properties, Curie depth, shape of magnetic bodies etc. Going a step further in the methodology, we established under some approximation the formula of the power spectrum in the spherical cap domain. We will discuss the usefulness of this new tool to test the quality of our regional model but also illustrate how it may be used to quantify a possible spectral gap in the available magnetic field measurements. We will then present some preliminary geophysical interpretations of the lithospheric field model over Southern Africa in the spectral and spatial domains.

  14. Alien Phytogeographic Regions of Southern Africa: Numerical Classification, Possible Drivers, and Regional Threats

    PubMed Central

    Hugo, Sanet; Van Rensburg, Berndt J.; Van Wyk, Abraham E.; Steenkamp, Yolande

    2012-01-01

    The distributions of naturalised alien plant species that have invaded natural or semi-natural habitat are often geographically restricted by the environmental conditions in their new range, implying that alien species with similar environmental requirements and tolerances may form assemblages and characterise particular areas. The aim of this study was to use objective numerical techniques to reveal any possible alien phytogeographic regions (i.e. geographic areas with characteristic alien plant assemblages) in southern Africa. Quarter degree resolution presence records of naturalised alien plant species of South Africa, Lesotho, Swaziland, Namibia and Botswana were analysed through a divisive hierarchical classification technique, and the output was plotted on maps for further interpretation. The analyses revealed two main alien phytogeographic regions that could be subdivided into eight lower level phytogeographic regions. Along with knowledge of the environmental requirements of the characteristic species and supported by further statistical analyses, we hypothesised on the main drivers of alien phytogeographic regions, and suggest that environmental features such as climate and associated biomes were most important, followed by human activities that modify climatic and vegetation features, such as irrigation and agriculture. Most of the characteristic species are not currently well-known as invasive plant species, but many may have potential to become troublesome in the future. Considering the possibility of biotic homogenization, these findings have implications for predicting the characteristics of the plant assemblages of the future. However, the relatively low quality of the dataset necessitates further more in-depth studies with improved data before the findings could be directly beneficial for management. PMID:22574145

  15. International migration and sustainable human development in eastern and southern Africa.

    PubMed

    Oucho, J O

    1995-01-01

    International migration in eastern and southern Africa (ESA) is rarely addressed in population and development policies or regional organizations, and regional organizations must in the articulation of sustainable shared development identify the role of international migration. Poor quality data on international migration hampers analysis. Sustainable, shared, and human development within the region are subregional issues. Permanent migration is characterized among ESA countries as increasing demographic ethnic pluralism that may result in redrawing of territorial boundaries and further population movement. Portuguese and Arab settlement and integration in eastern areas resulted in coexistence, while European immigration to South Africa resulted in racial segregation. Modern colonial settlement and the aftermath of political conflict resulted in independent countries after the 1960s and outmigration of nonAfrican groups. Much of the labor migration in ESA is unskilled workers moving to South African mining regions. Labor migration to Zimbabwe and Zambia declined after the 1960s. The formation of the Common Market for ESA and the potential merger with the Preferential Trade Area and South African Development Community is a key approach to integration of migration into regional cooperation and shared development. Refugee movements create the most problems. Prior to 1992 ESA countries accounted for 83.4% of refugees, particularly in Mozambique, Ethiopia, and Somalia. Some countries blame poor economic performance on the deluge of refugees. Illegal migration is currently detected because of the required work permits, but the adoption of the Common Market would obscure this phenomenon. Human development is affected most by migrations related to drought, labor migration to strong economic areas, and return migration. The Inter-Governmental Authority on Drought and Development needs to become more active and establish better policies on nomadic and refugee movements and

  16. Lithosphere Structure in Southern Africa: Mantle Density, Dynamic Topography, Moho Sharpness, and Kimberlite Magmatism

    NASA Astrophysics Data System (ADS)

    Artemieva, I. M.; Vinnik, L. P.

    2015-12-01

    In southern Africa, both the Archean and Proterozoic blocks have the topography 500-700 m higher than in any other craton worldwide, except for the Tanzanian craton. An unusually high topography may be caused by a low density of the cratonic lithospheric mantle and/or by the dynamic support of the mantle with origin below the depth of isostatic compensation (assumed to be at the lithosphere base). We use free-board constraints to examine the relative contributions of the both factors to surface topography in the cratons of southern Africa and present regional model of density structure of the lithospheric mantle. The results indicate that 0.5-1.0 km of topography requires the dynamic contribution from the sublithospheric mantle because it cannot be explained by the lithosphere structure within the petrologically permitted range of mantle densities. The calculated lithospheric mantle density values are in an overall agreement with xenolith-based data and show an overall trend in mantle density increase from Archean to younger lithospheric terranes. Notable exceptions are the Limpopo belt and the Bushveld Intrusion Complex, which have an increased mantle density, probably as a result of melt-metasomatism. The Western Cape Fold Belt has a moderately depleted mantle with density within the range expected for Phanerozoic mantle, while mantle densities beneath the Eastern Cape Fold Belt require the presence of a significant amount of eclogite in the mantle. Mantle density structure correlates with distribution of kimberlites and with seismic velocity contrast across the Moho: kimberlite-rich regions have sharp Moho and low-density (3.32-3.33 g/cc) mantle, while kimberlite-poor regions have transient Moho and denser mantle (3.34-3.35 g/cc). We explain this pattern by melt-metasomatism which affects both mantle depletion and the Moho sharpness. We also find that regions with high mantle density host non-diamondiferous kimberlites, while diamondiferous kimberlites are

  17. Development of a locally sustainable functional food based on mutandabota, a traditional food in southern Africa.

    PubMed

    Mpofu, Augustine; Linnemann, Anita R; Sybesma, Wilbert; Kort, Remco; Nout, M J R; Smid, Eddy J

    2014-05-01

    A probiotic dairy product was developed on the basis of a traditional dish called mutandabota to enable resource-poor populations in southern Africa to benefit from a functional food. Mutandabota is widely consumed in rural southern Africa, making it an ideal food matrix to carry probiotics. First, a process to produce probiotic mutandabota was designed. Raw cow milk was boiled and subsequently cooled to ambient temperature (25°C). Next, dry pulp from the fruit of the baobab tree (Adansonia digitata L.) was added to the milk at a concentration of 4% (wt/vol). This mixture was inoculated with the probiotic Lactobacillus rhamnosus yoba and left to ferment for 24h, while the growth of the bacterial culture was monitored. Final ingredients were then added to produce probiotic mutandabota that had 14% (wt/vol) baobab fruit pulp and 7% (wt/vol) sugar in cow milk. The pH of probiotic mutandabota was pH 3.5, which ensures that the product is microbiologically safe. The viable plate count of L. rhamnosus yoba increased from 5.8 ± 0.3 log cfu/mL at the point of inoculation to 8.8 ± 0.4 log cfu/mL at the moment of consumption, thereby meeting the criterion to have a viable count of the probiotic bacterium in excess of 6 log cfu/mL of a product. Baobab fruit pulp at 4% promoted growth of L. rhamnosus yoba with a maximal specific growth rate (μmax) of 0.6 ± 0.2/h at 30°C. The developed technology, though specific for this particular product, has potential to be applied for the delivery of probiotics through a variety of indigenous foods in different regions of the world. Upon consumption, probiotic mutandabota is expected to improve the population's intestinal health, which is especially relevant for vulnerable target groups such as children and elderly people. PMID:24630646

  18. The potential value of seasonal forecasts in a changing climate in southern Africa

    NASA Astrophysics Data System (ADS)

    Winsemius, H. C.; Dutra, E.; Engelbrecht, F. A.; Archer Van Garderen, E.; Wetterhall, F.; Pappenberger, F.; Werner, M. G. F.

    2014-04-01

    Subsistence farming in southern Africa is vulnerable to extreme weather conditions. The yield of rain-fed agriculture depends largely on rainfall-related factors such as total seasonal rainfall, anomalous onsets and lengths of the rainy season and the frequency of occurrence of dry spells. Livestock, in turn, may be seriously impacted by climatic stress with, for example, exceptionally hot days, affecting condition, reproduction, vulnerability to pests and pathogens and, ultimately, morbidity and mortality. Climate change may affect the frequency and severity of extreme weather conditions, impacting on the success of subsistence farming. A potentially interesting adaptation measure comprises the timely forecasting and warning of such extreme events, combined with mitigation measures that allow farmers to prepare for the event occurring. This paper investigates how the frequency of extreme events may change in the future due to climate change over southern Africa and, in more detail, the Limpopo Basin using a set of climate change projections from several regional climate model downscalings based on an extreme climate scenario. Furthermore, the paper assesses the predictability of these indicators by seasonal meteorological forecasts of the European Centre for Medium-Range Weather Forecasts (ECMWF) seasonal forecasting system. The focus is on the frequency of dry spells as well as the frequency of heat stress conditions expressed in the temperature heat index. In areas where their frequency of occurrence increases in the future and predictability is found, seasonal forecasts will gain importance in the future, as they can more often lead to informed decision-making to implement mitigation measures. The multi-model climate projections suggest that the frequency of dry spells is not likely to increase substantially, whereas there is a clear and coherent signal among the models of an increase in the frequency of heat stress conditions by the end of the century. The

  19. Responses to satellite remote sensing opportunities in East and Southern Africa

    NASA Astrophysics Data System (ADS)

    Falconer, Allan; Odenyo, Victor A. O.

    Since 1978 the U.S. Agency for International Development (USAID) has funded a regional remote sensing project for East and Southern Africa. The project, hosted by the Regional Centre for Services in Surveying Mapping and Remote Sensing, has provided a programme of training courses, user services and project support. This included the equipping and establishment of a photo-laboratory complex for processing Landsat images and the provision of advice and support for agencies undertaking natural resources analysis. Response to the training programme has been very good. Courses are usually over subscribed and there is a continued demand for training. Assessments of the courses by participants are highly positive and the courses have featured consultants of international calibre. Requests for follow-up courses, and for specialist group training indicate a strong response to this training activity. User services are active, consultations with staff, use of the browse file and interpretation equipment and the purchase of data for project work all produce an average demand of 12 active enquiries per working week. The photo-laboratory is particularly active and demand for products exceeds available capacity. Project work is now being supported but limited resources restrict the range and amount of project activity. Response to the opportunities offered for projects has been favourable and this activity is ripe for expansion. The difficulty in expanding to meet the expressed demand is primarily financial. The east and southern Africa region is not economically strong and has a great need for natural resources data for development work and planning. The responses to satellite remote sensing opportunities will be limited by these financial constraints which effectively means by the level of international aid directed to this activity. For such aid to be effective it must be coordinated and firmly attached to the region. Such coordinated aid programmes would avoid fragmentation

  20. An Overview of SASSCAL Activities Supporting Interdisciplinary Water Research in Southern Africa

    NASA Astrophysics Data System (ADS)

    Helmschrot, J.; Jürgens, N.

    2013-12-01

    Climate change will affect current water resources in sub-Saharan Africa. Considering projected climate scenarios, the overall challenge in the southern African region is to secure water at sufficient quality and quantity for both, the stability of ecosystems with their functions and services as well as for human well-being (potable water, irrigation water, and water for industrial use). Thus, improved understanding of the linkages between hydrological (including hydro-geological) components of ecosystems and society is needed as a precondition to develop sustainable management strategies for integrated water resources management in this data scarce region. Funded by the German Ministry of Education and Research (BMBF), 87 research projects of the SASSCAL Initiative (Southern African Science Service Centre for Climate Change and Adaptive Land Management) focus on providing information and services allowing for a better understanding and assessment of the impact of climate and land management changes in five thematic areas, namely climate, water, agriculture, forestry and biodiversity. Water-related research activities in SASSCAL aim to improve our knowledge on the complex interactions and feedbacks between surface and groundwater dynamics and resources as well as land surface processes in selected regions of the participating countries (Angola, Botswana, Namibia, South Africa and Zambia). The main objective of this joint and integrated research effort is to develop reliable hydrological and hydro-geological baseline data along with a set of analytical methods to strengthen the research capacity of the water sector of the Southern African region. Thereby, SASSCAL contributes to the implemention of integrated water resources management strategies for improved trans-boundary river management and resources usage in the perspective of global climate and land management changes. Here, we present an overview and first results of ongoing studies conducted by various

  1. Establishing an Online Continuing and Professional Development Library for Nurses and Midwives in East, Central, and Southern Africa.

    PubMed

    Hosey, Kristen N; Kalula, Alphonce; Voss, Joachim

    2016-01-01

    Over the past 4 years, the African Health Profession Regulatory Collaborative for nurses and midwives has supported 12 countries establish national continuing and professional development frameworks and programs, linking continuing education to nursing and midwifery re-licensure through technical assistance and improvement grants. However, lack of electronic media and rural practice sites, differences in priority content, and varying legal frameworks make providing accessible, certifiable, and up-to-date online continuing education content for the more than 300,000 nurses and midwives in the 17 member countries of the East, Central, and Southern Africa College of Nursing a major challenge. We report here on how the East, Central, and Southern Africa College of Nursing, with technical assistance from an Afya Bora Fellow, developed an online continuing professional development library hosted on their Web site using data collected in a survey of nursing and midwifery leaders in the region. PMID:27086190

  2. Shifts in Köppen-Geiger climate zones over southern Africa in relation to key global temperature goals

    NASA Astrophysics Data System (ADS)

    Engelbrecht, Christien J.; Engelbrecht, Francois A.

    2016-01-01

    Potential changes in Köppen-Geiger climate zones over southern Africa (Africa south of 22 °S) under future climate change are investigated using an ensemble of high-resolution projections of a regional climate model. The projections are performed under the A2 scenario of the Special Report on Emission Scenarios (SRES), and changes are presented for those times in the future when the increase in global average surface temperature reaches thresholds of 1, 2, and 3 °C, relative to the present-day baseline climatology. Widespread shifts in climate regimes are projected, of which the southern and eastern expansion of the hot desert and hot steppe zones is the most prominent. From occupying 33.1 and 19.4 % of southern Africa under present-day climate, these regions are projected to occupy between 47.3 and 59.7 % (hot desert zone) and 24.9 and 29.9 % (hot steppe zone) of the region in a future world where the global temperature has increased by 3 °C. The cold desert and cold steppe zones are projected to decrease correspondingly. The temperate regions of eastern South Africa, the Cape south coast, and winter rainfall region of the southwestern Cape are also projected to contract. An expansion of the hot steppe zone into the cold steppe and temperate zones may favor the intrusion of trees (and therefore the savanna biome) into the most pristine grasslands of southern Africa. However, the correlative climate-vegetation approach of using projected changes in Köppen-Geiger zones to infer future vegetation patterns is of limited value in the savanna complex of southern Africa, where complex feedbacks occur between carbon dioxide (CO2) concentrations, trees, C4 grasses, fire, and climate. The present-day temperate Cape Fynbos regime may come under increasing pressure as the encompassing temperate zone is invaded mainly from the east by the hot steppe climate regime under climate change, with the incidence of Fynbos fires also becoming more likely in a generally warmer and

  3. Africa.

    ERIC Educational Resources Information Center

    Happel, Sue; Loeb, Joyce

    Although the activities in this unit are designed primarily for students in the intermediate grades, the document's text, illustrations, and bibliographic references are suitable for anyone interested in learning about Africa. Following a brief introduction and map work, the document is arranged into six sections. Section 1 traces Africa's history…

  4. Africa.

    ERIC Educational Resources Information Center

    Martz, Carlton

    2001-01-01

    This publication explores issues related to Africa. It examines the U.S. response to the Barbary pirate states (Morocco, Algiers, Tunis, Tripoli) in the early 19th century; the current AIDS crisis in Africa; and 14th century Mali and other Islamic lands through the eyes of Ibn Battuta, who traveled throughout the Muslim world. Each article…

  5. Love wave tomography in southern Africa from a two-plane-wave inversion method

    NASA Astrophysics Data System (ADS)

    Li, Aibing; Li, Lun

    2015-08-01

    Array measurements of surface wave phase velocity can be biased by multipath arrivals. A two-plane-wave (TPW) inversion method, in which the incoming wavefield is represented by the interference of two plane waves, is able to account for the multipath effect and solve for laterally varying phase velocity. Despite broad applications of the TPW method, its usage has been limited to Rayleigh waves. In this study, we have modified the TPW approach and applied it to Love waves. Main modifications include decomposing Love wave amplitude on the transverse component to x and y components in a local Cartesian system for each earthquake and using both components in the inversion. Such decomposition is also applied to the two plane waves to predict the incoming wavefield of an earthquake. We utilize fundamental mode Love wave data recorded at 85 broad-band stations from 69 distant earthquakes and solved for phase velocity in nine frequency bands with centre periods ranging from 34 to 100 s. The average phase velocity in southern Africa increases from 4.30 km s-1 at 34 s to 4.87 km s-1 at 100 s. Compared with predicted Love wave phase velocities from the published 1-D SV velocity model and radial anisotropy model in the region, these values are compatible from 34 to 50 s and slightly higher beyond 50 s, indicating radial anisotropy of VSH > VSV in the shallow upper mantle. A high Love wave velocity anomaly is imaged in the central and southern Kaapvaal craton at all periods, reflecting a cold and depleted cratonic lithosphere. A low velocity anomaly appears in the Bushveld Complex from 34 to 50 s, which can be interpreted as being caused by high iron content from an intracratonic magma intrusion. The modified TPW method provides a new way to measure Love wave phase velocities in a regional array, which are essential in developing radial anisotropic models and understanding the Earth structure in the crust and upper mantle.

  6. The nexus between integrated natural resources management and integrated water resources management in southern Africa

    NASA Astrophysics Data System (ADS)

    Twomlow, Stephen; Love, David; Walker, Sue

    The low productivity of smallholder farming systems and enterprises in the drier areas of the developing world can be attributed mainly to the limited resources of farming households and the application of inappropriate skills and practices that can lead to the degradation of the natural resource base. This lack of development, particularly in southern Africa, is of growing concern from both an agricultural and environmental perspective. To address this lack of progress, two development paradigms that improve land and water productivity have evolved, somewhat independently, from different scientific constituencies. One championed by the International Agricultural Research constituency is Integrated Natural Resource Management (INRM), whilst the second championed predominantly by Environmental and Civil Engineering constituencies is Integrated Water Resources Management (IWRM). As a result of similar objectives of working towards the millennium development goals of improved food security and environmental sustainability, there exists a nexus between the constituencies of the two paradigms, particularly in terms of appreciating the lessons learned. In this paper lessons are drawn from past INRM research that may have particular relevance to IWRM scientists as they re-direct their focus from blue water issues to green water issues, and vice-versa. Case studies are drawn from the management of water quality for irrigation, green water productivity and a convergence of INRM and IWRM in the management of gold panning in southern Zimbabwe. One point that is abundantly clear from both constituencies is that ‘one-size-fits-all’ or silver bullet solutions that are generally applicable for the enhancement of blue water management/formal irrigation simply do not exist for the smallholder rainfed systems.

  7. Gender-based violence and HIV: relevance for HIV prevention in hyperendemic countries of southern Africa.

    PubMed

    Andersson, Neil; Cockcroft, Anne; Shea, Bev

    2008-12-01

    Gender-based violence (GBV) is common in southern Africa. Here we use GBV to include sexual and non-sexual physical violence, emotional abuse, and forms of child sexual abuse. A sizeable literature now links GBV and HIV infection.Sexual violence can lead to HIV infection directly, as trauma increases the risk of transmission. More importantly, GBV increases HIV risk indirectly. Victims of childhood sexual abuse are more likely to be HIV positive, and to have high risk behaviours.GBV perpetrators are at risk of HIV infection, as their victims have often been victimised before and have a high risk of infection. Including perpetrators and victims, perhaps one third of the southern African population is involved in the GBV-HIV dynamic.A randomised controlled trial of income enhancement and gender training reduced GBV and HIV risk behaviours, and a trial of a learning programme reported a non-significant reduction in HIV incidence and reduction of male risk behaviours (primary prevention). Interventions among survivors of GBV can reduce their HIV risk (secondary prevention). Various strategies can reduce spread of HIV from infected GBV survivors (tertiary prevention). Dealing with GBV could have an important effect on the HIV epidemic.A policy shift is necessary. HIV prevention policy should recognise the direct and indirect implications of GBV for HIV prevention, the importance of perpetrator dynamics, and that reduction of GBV should be part of HIV prevention programmes. Effective interventions are likely to include a structural component, and a GBV awareness component. PMID:19033757

  8. AIDS among older children and adolescents in Southern Africa: projecting the time course and magnitude of the epidemic

    PubMed Central

    Ferrand, Rashida A; Corbett, Elizabeth L; Wood, Robin; Hargrove, John; Ndhlovu, Chiratidzo E; Cowan, Frances M; Gouws, Eleanor; Williams, Brian G

    2012-01-01

    Objective An AIDS epidemic among older children and adolescents is clinically apparent in Southern Africa. We estimated the likely scale and time course of the epidemic in older survivors of vertical HIV infection. Design We modelled demographic, HIV prevalence, mother-to-child transmission (MTCT) and child survival data to project HIV burden among older children in two Southern African countries at different stages of severe HIV epidemics. Using measured survival data for children, we estimate that 64% of HIV-infected infants are fast-progressors with median survival=0.64 years and 36% are slow-progressors with median survival=16.0 years. We confirmed model validity by comparing model predictions to available epidemiological data. Findings Without treatment, HIV prevalence among 10-year olds in South Africa is expected to increase from 2.1% in 2008 to 3.3% in 2020 while in Zimbabwe, it will decrease from 3.2% in 2008 to 1.6% in 2020. Deaths among untreated slow-progressors will increase in South Africa from 7000/year in 2008 to 23,000/year in 2030, and in Zimbabwe from 8000/year in 2008 to peak at 9700/year in 2014. Drugs to prevent MTCT could reduce death rate in 2030 to 8700/year in South Africa and to 2800/year in Zimbabwe in 2014. Conclusions A substantial epidemic of HIV/AIDS in older survivors of MTCT is emerging in Southern Africa. The lack of direct observations of survival in slow-progressors has resulted in failure to anticipate the magnitude of the epidemic and to adequately address the clinical needs of HIV-infected older children and adolescents. Better HIV diagnostic and care services for this age-group are urgently required. PMID:19684508

  9. History and development of research on wildlife parasites in southern Africa, with emphasis on terrestrial mammals, especially ungulates

    PubMed Central

    Junker, Kerstin; Horak, Ivan G.; Penzhorn, Banie

    2014-01-01

    The history of wildlife parasitology in South Africa, and to some extent southern Africa, is reviewed, giving a brief overview of the early years and following its development from the founding of the Onderstepoort Veterinary Institute in 1908 until the turn of the century. An emphasis is placed on game species. The main findings on protozoan parasites, including those of carnivores, are presented, starting in the 1890s and leading up to the first decade of the 21st century. Important developments with regard to the studies of arthropod and helminth parasites took place during a period of three decades, starting from the 1970s. Because of the sheer volume of work done by parasitologists during this time, this particular part of the overview concentrates on South African authors or authors working in South Africa at the time, and is limited to hosts that are members of the order Perissodactyla and the superorder Cetartiodactyla. PMID:25830101

  10. Using Tournament Angler Data to Rapidly Assess the Invasion Status of Alien Sport Fishes (Micropterus spp.) in Southern Africa.

    PubMed

    Hargrove, John S; Weyl, Olaf L F; Allen, Micheal S; Deacon, Neil R

    2015-01-01

    Fishes are one of the most commonly introduced aquatic taxa worldwide, and invasive fish species pose threats to biodiversity and ecosystem function in recipient waters. Considerable research efforts have focused on predicting the invasibility of different fish taxa; however, accurate records detailing the establishment and spread of invasive fishes are lacking for large numbers of fish around the globe. In response to these data limitations, a low-cost method of cataloging and quantifying the temporal and spatial status of fish invasions was explored. Specifically, angler catch data derived from competitive bass angling tournaments was used to document the distribution of 66 non-native populations of black bass (Micropterus spp.) in southern Africa. Additionally, catch data from standardized tournament events were used to assess the abundance and growth of non-native bass populations in southern Africa relative to their native distribution (southern and eastern United States). Differences in metrics of catch per unit effort (average number of fish retained per angler per day), daily bag weights (the average weight of fish retained per angler), and average fish weight were assessed using catch data from 14,890 angler days of tournament fishing (11,045 days from South Africa and Zimbabwe; 3,845 days from the United States). No significant differences were found between catch rates, average daily bag weight, or the average fish weight between countries, suggesting that bass populations in southern Africa reach comparable sizes and numbers relative to waters in their native distribution. Given the minimal cost associated with data collection (i.e. records are collected by tournament organizers), the standardized nature of the events, and consistent bias (i.e. selection for the biggest fish in a population), the use of angler catch data represents a novel approach to infer the status and distribution of invasive sport fish. PMID:26047487

  11. Using Tournament Angler Data to Rapidly Assess the Invasion Status of Alien Sport Fishes (Micropterus spp.) in Southern Africa

    PubMed Central

    Hargrove, John S.; Weyl, Olaf L. F.; Allen, Micheal S.; Deacon, Neil R.

    2015-01-01

    Fishes are one of the most commonly introduced aquatic taxa worldwide, and invasive fish species pose threats to biodiversity and ecosystem function in recipient waters. Considerable research efforts have focused on predicting the invasibility of different fish taxa; however, accurate records detailing the establishment and spread of invasive fishes are lacking for large numbers of fish around the globe. In response to these data limitations, a low-cost method of cataloging and quantifying the temporal and spatial status of fish invasions was explored. Specifically, angler catch data derived from competitive bass angling tournaments was used to document the distribution of 66 non-native populations of black bass (Micropterus spp.) in southern Africa. Additionally, catch data from standardized tournament events were used to assess the abundance and growth of non-native bass populations in southern Africa relative to their native distribution (southern and eastern United States). Differences in metrics of catch per unit effort (average number of fish retained per angler per day), daily bag weights (the average weight of fish retained per angler), and average fish weight were assessed using catch data from 14,890 angler days of tournament fishing (11,045 days from South Africa and Zimbabwe; 3,845 days from the United States). No significant differences were found between catch rates, average daily bag weight, or the average fish weight between countries, suggesting that bass populations in southern Africa reach comparable sizes and numbers relative to waters in their native distribution. Given the minimal cost associated with data collection (i.e. records are collected by tournament organizers), the standardized nature of the events, and consistent bias (i.e. selection for the biggest fish in a population), the use of angler catch data represents a novel approach to infer the status and distribution of invasive sport fish. PMID:26047487

  12. Teacher Migration Impact: A Review in the Context of Quality Education Provision and Teacher Training in Higher Education in Southern Africa

    ERIC Educational Resources Information Center

    Brown, B.

    2008-01-01

    Teacher mobility has become a common feature of the cross-border flows and transnational networks that constitute globalisation. International and intraregional migration of teachers is an important factor in education provision and management in countries in the Southern Africa region, for example Botswana and South Africa. In an increasingly…

  13. Evidence of a large cooling between 1690 and 1740 AD in southern Africa

    PubMed Central

    Sundqvist, H. S.; Holmgren, K.; Fohlmeister, J.; Zhang, Q.; Matthews, M. Bar; Spötl, C.; Körnich, H.

    2013-01-01

    A 350-year-long, well-dated δ18O stalagmite record from the summer rainfall region in South Africa is positively correlated with regional air surface temperatures at interannual time scales. The coldest period documented in this record occurred between 1690 and 1740, slightly lagging the Maunder Minimum (1645–1710). A temperature reconstruction, based on the correlation between regional surface temperatures and the stalagmite δ18O variations, indicates that parts of this period could have been as much as 1.4°C colder than today. Significant cycles of 22, 11 and 4.8 years demonstrate that the solar magnetic and the El Niño-Southern Oscillation cycle could be important drivers of multidecadal to interannual climate variability in this region. The observation that the most important driver of stalagmite δ18O on interannual time scales from this subtropical region is regional surface temperature cautions against deterministic interpretations of δ18O variations in low-latitude stalagmites as mainly driven by the amount of precipitation.

  14. Linking avian communities and avian influenza ecology in southern Africa using epidemiological functional groups

    PubMed Central

    2012-01-01

    The ecology of pathogens, and particularly their emergence in multi-host systems, is complex. New approaches are needed to reduce superficial complexities to a level that still allows scientists to analyse underlying and more fundamental processes. One promising approach for simplification is to use an epidemiological-function classification to describe ecological diversity in a way that relates directly to pathogen dynamics. In this article, we develop and apply the epidemiological functional group (EFG) concept to explore the relationships between wild bird communities and avian influenza virus (AIV) in three ecosystems in southern Africa. Using a two year dataset that combined bird counts and bimonthly sampling for AIV, we allocated each bird species to a set of EFGs that captured two overarching epidemiological functions: the capacity of species to maintain AIV in the system, and their potential to introduce the virus. Comparing AIV prevalence between EFGs suggested that the hypothesis that anseriforms (ducks) and charadriiforms (waders) drive AIV epidemiology cannot entirely explain the high prevalence observed in some EFGs. If anseriforms do play an important role in AIV dynamics in each of the three ecosystems, the role of other species in the local maintenance of AIV cannot be ruled out. The EFG concept thus helped us to identify gaps in knowledge and to highlight understudied bird groups that might play a role in AIV epidemiology. In general, the use of EFGs has potential for generating a range of valuable insights in epidemiology, just as functional group approaches have done in ecology. PMID:23101696

  15. Oil and gas developments in central and southern Africa in 1982

    SciTech Connect

    McGrew, H.J.

    1983-10-01

    Exploratory activity in central and southern Africa continued to be strong during 1982. Seismic operations decreased, but there was a marked increase in the amount of aeromagnetic control obtained. Oil production continued the drop which began in 1981 due to the world oversupply. There were few new concessions taken by the international oil companies. Several small projects required the acquisition of relatively small amounts of land. A notable exception was in Gabon where Tenneco and Amoco have gained strong land positions. The east African countries are preparing for increased land acquisition. Seismic activity declined from 365 party-months in 1981 to 296 party-months in 1982. The amount of control obtained, however, increased substantially to 127,518 km. The acquisition of 3-D control increased by about 50% during the year as this technique was being used more commonly to delineate structures prior to development drilling. Forty-eight new-field wildcats resulted in discoveries, compared with 44 the previous year. There were 281 development wells. In all, 464 wells were drilled to account for 3.6 million ft of hole. Oil production was 662,871,768 bbl, a decrease of 5.8% from 1981. Cumulative production has now exceeded 11 billion bbl.

  16. Structural barriers to ART adherence in Southern Africa: Challenges and potential ways forward.

    PubMed

    Kagee, A; Remien, R H; Berkman, A; Hoffman, S; Campos, L; Swartz, L

    2011-01-01

    Structural barriers to antiretroviral therapy (ART) adherence are economic, institutional, political and cultural factors, that collectively influence the extent to which persons living with HIV follow their medication regimens. We identify three sets of structural barriers to ART adherence that are salient in Southern Africa: poverty-related, institutional, and political and cultural. Examples of poverty-related barriers are competing demands in the context of resource-constrained settings, the lack of transport infrastructure, food insecurity, the role of disability grants and poor social support. Examples of institutional factors are logistical barriers, overburdened health care facilities, limited access to mental health services and difficulties in ensuring adequate counselling. Examples of political and cultural barriers are controversies in the provision of treatment for AIDS, migration, traditional beliefs about HIV and AIDS, poor health literacy and gender inequalities. In forging a way forward, we identify ways in which individuals, communities and health care systems may overcome some of these structural barriers. Finally, we make recommendations for further research on structural barriers to ART adherence. In all likelihood, enhancing adherence to ART requires the efforts of a variety of disciplines, including public health, psychology, anthropology, sociology and medicine. PMID:20509066

  17. Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season

    SciTech Connect

    Kirchstetter, Thomas W.; Novakov, T.; Hobbs, Peter V.; Magi, Brian

    2002-06-17

    Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60 percent larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60 percent more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18/2610.06) is lower than that of samples collected in the regional haze (0.25/2610.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple source apportionment indicates that biomass smoke contributes about three-quarters of the aerosol burden in the regional haze, while other sources (e.g., fossil fuel burning) contribute the remainder.

  18. An Integrated Land Use - Land Cover Change Model for the Southern Africa Region

    NASA Astrophysics Data System (ADS)

    Desanker, P. V.

    2001-12-01

    A land use change model covering the Miombo region of Southern Africa region is presented. The model includes a structure that recognizes the scales at which land use change decisions are made in the region, namely the traditional authority for subsistence agricultural land use, and includes social-economic and biophysical constraints to land use at multiple levels. Land cover information for the 1990's based on maps derived from Landsat Thematic Mapper data are used to initiative the model. The model, called MELT, can be used to examine impacts of land use change on carbon pools, emissions from land use change (slash and burn agriculture or as a result of soil carbon changes), and spatial patterning of land cover. MELT provides a suitable representation of the process of land use in this region, and will be essential in providing the correct context for observed fire and emissions across the region of the SAFARI 2000 initiative. MELT is implemented using an object-oriented approach, and allows easy linkage with impacts models.

  19. Dynamic Locomotor Capabilities Revealed by Early Dinosaur Trackmakers from Southern Africa

    PubMed Central

    Wilson, Jeffrey A.; Marsicano, Claudia A.; Smith, Roger M. H.

    2009-01-01

    Background A new investigation of the sedimentology and ichnology of the Early Jurassic Moyeni tracksite in Lesotho, southern Africa has yielded new insights into the behavior and locomotor dynamics of early dinosaurs. Methodology/Principal Findings The tracksite is an ancient point bar preserving a heterogeneous substrate of varied consistency and inclination that includes a ripple-marked riverbed, a bar slope, and a stable algal-matted bar top surface. Several basal ornithischian dinosaurs and a single theropod dinosaur crossed its surface within days or perhaps weeks of one another, but responded to substrate heterogeneity differently. Whereas the theropod trackmaker accommodated sloping and slippery surfaces by gripping the substrate with its pedal claws, the basal ornithischian trackmakers adjusted to the terrain by changing between quadrupedal and bipedal stance, wide and narrow gauge limb support (abduction range = 31°), and plantigrade and digitigrade foot posture. Conclusions/Significance The locomotor adjustments coincide with changes in substrate consistency along the trackway and appear to reflect ‘real time’ responses to a complex terrain. It is proposed that these responses foreshadow important locomotor transformations characterizing the later evolution of the two main dinosaur lineages. Ornithischians, which shifted from bipedal to quadrupedal posture at least three times in their evolutionary history, are shown to have been capable of adopting both postures early in their evolutionary history. The substrate-gripping behavior demonstrated by the early theropod, in turn, is consistent with the hypothesized function of pedal claws in bird ancestors. PMID:19806213

  20. Structural barriers to ART adherence in Southern Africa: challenges and potential ways forward

    PubMed Central

    KAGEE, A.; REMIEN, R.H.; BERKMAN, A.; HOFFMAN, S.; CAMPOS, L.; SWARTZ, L.

    2010-01-01

    Structural barriers to antiretroviral treatment (ART) adherence are economic, institutional, political and cultural factors, that collectively influence the extent to which persons living with HIV follow their medication regimens. We identify three sets of structural barriers to ART adherence that are salient in Southern Africa: poverty-related, institutional, and political and cultural. Examples of poverty-related barriers are competing demands in the context of resource-constrained settings, the lack of transport infrastructure, food insecurity, the role of disability grants and poor social support. Examples of institutional factors are logistical barriers, overburdened health care facilities, limited access to mental health services and difficulties in ensuring adequate counseling. Examples of political and cultural barriers are controversies in the provision of treatment for AIDS, migration, traditional beliefs about HIV and AIDS, poor health literacy and gender inequalities. In forging a way forward, we identify ways in which individuals, communities and health care systems may overcome some of these structural barriers. Finally, we make recommendations for further research on structural barriers to ART adherence. In all likelihood, enhancing adherence to ART requires the efforts of a variety of disciplines, including public health, psychology, anthropology, sociology and medicine. PMID:20509066

  1. Hydrological drought forecasting and skill assessment for the Limpopo river basin, Southern Africa

    NASA Astrophysics Data System (ADS)

    Trambauer, Patricia; Werner, Micha; Winsemius, Hessel; Maskey, Shreedhar; Dutra, Emanuel

    2014-05-01

    Ensemble hydrological predictions are normally obtained by forcing hydrological models with ensembles of atmospheric forecasts produced by climate models, and frequently applied for flood-forecasting purposes. The approach can be equally applied to forecasting drought at the seasonal time scale. Although this approach has to date not been applied widely, the importance of the subject is recognised and is gaining attention by the research community. The semi-arid Limpopo river basin in Southern Africa has experienced severe droughts in the past, which resulted in crop failures, high economic losses and the need for humanitarian aid. This paper addresses the seasonal prediction of hydrological drought for the Limpopo river basin by testing three forecasting systems. We seek to provide operational guidance to farmers and water mangers within the basin at the seasonal time scale by predicting the availability of water for irrigation and water supply, which are the most important water uses in the basin. In the first system (FS_S4) the PCR-GLOBWB hydrological model was forced with the output of a global atmospheric model, the ECMWF seasonal forecast system S4 (atmosphere-ocean coupled), which has a spatial resolution of about 70 km. An ensemble of hindcasts from the meteorological forecasting system was first obtained for the summer rainfall season over southern Africa for the period 1981 to 2010 to allow for testing of the system. The second forecasting system (FS_ESP) is based on the Ensemble Streamflow Prediction (ESP) procedure. In the ESP procedure the ensemble meteorological forecast is generated with re-sampled historical meteorological data. The hydrological model is then forced with this re-sampled data. FS_ESP allows measuring the skill that can be expected from initial states combined with climatology, and the comparison with the first system allows measuring the improvement when using the ECMWF seasonal forecast S4 compared to using the ESP forecast. A third

  2. The late Mesozoic and Cenozoic development of southern Africa: geological and geomorphological evidence for widespread denudation and epeirogenic uplift

    NASA Astrophysics Data System (ADS)

    Rowberry, Matt; McCarthy, Terence; Tooth, Stephen

    2010-05-01

    Southern Africa represents one of the world's classic passive continental margins. Despite numerous endeavours, elucidating the age and origin of some its most conspicuous topographic features (e.g. the highly-elevated continental interior, the marginal bulge, and the erosional escarpment) remains among the most intractable and controversial problems within geomorphological research. Recent advances in apatite fission track analysis have better constrained the timing and magnitude of those denudational episodes to have affected the region following continental separation during the Mesozoic. Moreover, similar developments in terrestrial cosmogenic isotope analysis have afforded insight into denudation rates over the past several hundred thousand years. Whilst these studies have provided invaluable information with regard to the denudational history of the region, establishing the timing and magnitude of epeirogenic uplift is far more conjectural as the stratigraphic record is necessarily removed by denudation. This paper proposes a new morphostratigraphic model for southern Africa, based on the integration of offshore sedimentary sequences, records of post-emplacement alkaline volcanic pipe erosion, and detailed topographic analyses. The latter of these includes a reappraisal of some of the data previously cited in support of substantial late Cenozoic uplift within southeastern Africa, including a more systematic analysis of longitudinal stream profiles derived from rivers in KwaZulu-Natal and the Eastern Cape. It is shown that southern Africa must have been graded to sea-level prior to the late Cretaceous. Thereafter, widespread uplift occurred most probably during the Oligocene. This uplift initiated denudational unloading of the continental periphery as steep valley heads coalesced to form an increasingly prominent escarpment. Broadly coeval isostatic adjustment led to the reestablishment of a ubiquitous marginal bulge, which was likely to have previously

  3. Africa and Applied Linguistics.

    ERIC Educational Resources Information Center

    Makoni, Sinfree, Ed.; Meinhof, Ulrike H., Ed.

    2003-01-01

    This collection of articles includes: "Introducing Applied Linguistics in Africa" (Sinfree Makoni and Ulrike H. Meinhof); "Language Ideology and Politics: A Critical Appraisal of French as Second Official Language in Nigeria" (Tope Omoniyi); "The Democratisation of Indigenous Languages: The Case of Malawi" (Themba Moyo); "Classroom Code-Switching…

  4. Origin of microseisms in equatorial and southern Africa from analysis of broadband arrays

    NASA Astrophysics Data System (ADS)

    Euler, G. G.; Wiens, D. A.; Nyblade, A.

    2010-12-01

    Using broadband array noise correlation and frequency-wavenumber analysis, we find evidence for 4 distinct origins of microseisms in the 10-200mHz band: an unusual source of Rayleigh waves at 35-40mHz located in the Bight of Bonny, several abyssal locations with enhanced P-wave production at 100-200mHz, and both coastal and abyssal Rayleigh wave sources that vary in bandwidth. We find no evidence of persistent seismic noise generation on land. Data analyzed were 1Hz vertical component recordings from the Cameroon, Southern Africa, Tanzania, and Ethiopia PASSCAL experiments. The Bonny microseism is characterized by 2 well-defined peaks at 36 & 38mHz and is found to have a location on the continental shelf in the northern portion of the Bight of Bonny. Our preliminary analysis finds that the microseism is well represented as a point source with a frequency-dependent location and horizontal slowness. Additional peaks near 61mHz and 69mHz are associated with increased Rayleigh waves sourced from the Bight of Bonny but are below the frequency range expected for a doubled frequency microseism (70-80mHz). Strong P-wave energy is found to originate from abyssal regions west of Retkjanes Ridge near Greenland, South of the Kerguelen Islands, and in the vicinity of the triple-junction formed by the African, South American & Antarctic plates. We propose that the locations represent optimal sea floor bathymetry for efficient conversion of nonlinearly interfering ocean swell to seismic P waves. Maputo bay and Sofala bay in Mozambique, the Western Cape coast in South Africa, and the North Atlantic are the dominant sources of microseismic Rayleigh waves outside of 35-40mHz. All noise sources identified in our study have a seasonal signature with peak noise generation in the winter months of each location implying their energy is derived from ocean swell of extratropical cyclones.

  5. Emplacement temperatures of pyroclastic and volcaniclastic deposits in kimberlite pipes in southern Africa

    NASA Astrophysics Data System (ADS)

    Fontana, Giovanni; Mac Niocaill, Conall; Brown, Richard J.; Sparks, R. Stephen J.; Field, Matthew

    2011-10-01

    Palaeomagnetic techniques for estimating the emplacement temperatures of volcanic deposits have been applied to pyroclastic and volcaniclastic deposits in kimberlite pipes in southern Africa. Lithic clasts were sampled from a variety of lithofacies from three pipes for which the internal geology is well constrained (the Cretaceous A/K1 pipe, Orapa Mine, Botswana, and the Cambrian K1 and K2 pipes, Venetia Mine, South Africa). The sampled deposits included massive and layered vent-filling breccias with varying abundances of lithic inclusions, layered crater-filling pyroclastic deposits, talus breccias and volcaniclastic breccias. Basalt lithic clasts in the layered and massive vent-filling pyroclastic deposits in the A/K1 pipe at Orapa were emplaced at >570°C, in the pyroclastic crater-filling deposits at 200-440°C and in crater-filling talus breccias and volcaniclastic breccias at <180°C. The results from the K1 and K2 pipes at Venetia suggest emplacement temperatures for the vent-filling breccias of 260°C to >560°C, although the interpretation of these results is hampered by the presence of Mesozoic magnetic overprints. These temperatures are comparable to the estimated emplacement temperatures of other kimberlite deposits and fall within the proposed stability field for common interstitial matrix mineral assemblages within vent-filling volcaniclastic kimberlites. The temperatures are also comparable to those obtained for pyroclastic deposits in other, silicic, volcanic systems. Because the lithic content of the studied deposits is 10-30%, the initial bulk temperature of the pyroclastic mixture of cold lithic clasts and juvenile kimberlite magma could have been 300-400°C hotter than the palaeomagnetic estimates. Together with the discovery of welded and agglutinated juvenile pyroclasts in some pyroclastic kimberlites, the palaeomagnetic results indicate that there are examples of kimberlites where phreatomagmatism did not play a major role in the generation

  6. Airborne spectral Measurements of Surface-Atmosphere Anisotropy for Several Surfaces and Ecosystem over Southern Africa

    NASA Technical Reports Server (NTRS)

    Gatebe, Charles K.; King, M. D.; Arnold, G. T.; Li, J. Y.; Lau, William K. M. (Technical Monitor)

    2001-01-01

    The Cloud Absorption Radiometer (CAR) was flown aboard the University of Washington Convair CV-580 research aircraft and took measurements on 23 flights between August 15 and September 16. On 12 of those flights, BRF measurements were obtained over different natural surfaces and ecosystem in southern Africa. The BRF measurements were done to characterize surface anisotropy in support of SAFARI 2000 science objectives principally to validate products from NASA's EOS satellites, and to parameterize and validate BRF models. In this paper we present results of BRFs taken over two EOS validation sites: Skukuza tower, South Africa (25.0 deg S, 31.5 deg E) and Mongu tower, Zambia (15.4 deg S, 23.3 deg E). Additional sites are also considered and include, Maun tower, Botswana (20.0 deg S, 23.5 deg E), Sowa Pan, Botswana (20.6 deg S, 26.2 deg E) and Etosha Pan, Namibia (19.0 deg S, 16.0 deg E). The CAR is capable of measuring scattered light in fourteen spectral bands. The scan mirror, rotating at 100 rpm, directs the light into a Dall-Kirkham telescope where the beam is split into nine paths. Eight light beams pass through beam splitters, dichroics, and lenses to individual detectors (0.34-1.27 micrometers), and finally are registered by eight data channels. They are sampled simultaneously and continuously. The ninth beam passes through a spinning filter wheel to an InSb detector cooled by a Stirling cycle cooler. Signals registered by the ninth data channel are selected from among six spectral channels (1.55-2.30 micrometers). The filter wheel can either cycle through all six spectral bands at a prescribed interval (usually changing filter every fifth scan line), or lock onto any one of the six spectral bands and sample it continuously. To measure the BRF of the surface-atmosphere system, the University of Washington CV-580 had to bank at a comfortable roll angle of approximately 20 degrees and fly in a circle about 3 km in diameter above the surface for roughly two

  7. Is tropospheric ozone over southern Africa really increasing? Evidence from sonde and aircraft profiles

    NASA Astrophysics Data System (ADS)

    Thompson, A. M.; Balashov, N. V.; Witte, J. C.; Coetzee, J. G. R.; Thouret, V.; Posny, F.

    2014-04-01

    Ozonesonde records from the early 1990's through 2008 over two subtropical stations, Irene (near Pretoria, South Africa) and Réunion Island (21° S, 55° W, ~3500 km NE of Irene in the Indian Ocean) were reported to exhibit free tropospheric (FT) ozone increases. Over Irene a large increase in the urban-influenced boundary layer (BL, 1.5-4 km) was also observed during the 18 year period, equivalent to 30% decade-1. Here we show that the Irene BL trend is at least partly due to a gradual change in the sonde launch times from early morning to the midday period. The FT ozone profiles over Irene in 1990-2007 are re-examined, filling in a 1995-1999 gap with ozone profiles taken by Measurements of Ozone by Airbus In-service Aircraft (MOZAIC) over nearby Johannesburg. A multivariate regression model that accounts for the annual ozone cycle, ENSO and possible tropopause changes was applied to monthly averaged Irene data from 4-11 km and to 1992-2011 Réunion sonde data from 4-15 km. Statistically significant trends appear predominantly in the middle and upper troposphere (UT, 4-11 km over Irene, 5-13 km over Réunion) in winter (June-August), with increases ~1 ppbv yr-1 over Irene and ~2 ppbv yr-1 over Réunion. These changes are equivalent to ~25% and 40-50% decade-1, respectively. Both stations also display smaller positive trends in summer with a 50% decade-1 ozone increase near the tropopause over Réunion in December. To explain the ozone increases, we investigated a time series of dynamical markers, e.g., potential vorticity (PV) at 330-350 K. PV affects UT ozone over Irene in November-December but displays little relationship to ozone over Réunion. A more likely reason for wintertime FT ozone increases over Irene and Réunion appears to be long-range transport of growing pollution in the Southern Hemisphere. The ozone increases are consistent with trajectory origins of air parcels sampled by the sondes and with recent NOx emissions trends estimated for Africa

  8. Migration and interaction in a contact zone: mtDNA variation among Bantu-speakers in Southern Africa.

    PubMed

    Barbieri, Chiara; Vicente, Mário; Oliveira, Sandra; Bostoen, Koen; Rocha, Jorge; Stoneking, Mark; Pakendorf, Brigitte

    2014-01-01

    Bantu speech communities expanded over large parts of sub-Saharan Africa within the last 4000-5000 years, reaching different parts of southern Africa 1200-2000 years ago. The Bantu languages subdivide in several major branches, with languages belonging to the Eastern and Western Bantu branches spreading over large parts of Central, Eastern, and Southern Africa. There is still debate whether this linguistic divide is correlated with a genetic distinction between Eastern and Western Bantu speakers. During their expansion, Bantu speakers would have come into contact with diverse local populations, such as the Khoisan hunter-gatherers and pastoralists of southern Africa, with whom they may have intermarried. In this study, we analyze complete mtDNA genome sequences from over 900 Bantu-speaking individuals from Angola, Zambia, Namibia, and Botswana to investigate the demographic processes at play during the last stages of the Bantu expansion. Our results show that most of these Bantu-speaking populations are genetically very homogenous, with no genetic division between speakers of Eastern and Western Bantu languages. Most of the mtDNA diversity in our dataset is due to different degrees of admixture with autochthonous populations. Only the pastoralist Himba and Herero stand out due to high frequencies of particular L3f and L3d lineages; the latter are also found in the neighboring Damara, who speak a Khoisan language and were foragers and small-stock herders. In contrast, the close cultural and linguistic relatives of the Herero and Himba, the Kuvale, are genetically similar to other Bantu-speakers. Nevertheless, as demonstrated by resampling tests, the genetic divergence of Herero, Himba, and Kuvale is compatible with a common shared ancestry with high levels of drift, while the similarity of the Herero, Himba, and Damara probably reflects admixture, as also suggested by linguistic analyses. PMID:24901532

  9. Migration and Interaction in a Contact Zone: mtDNA Variation among Bantu-Speakers in Southern Africa

    PubMed Central

    Barbieri, Chiara; Vicente, Mário; Oliveira, Sandra; Bostoen, Koen; Rocha, Jorge; Stoneking, Mark; Pakendorf, Brigitte

    2014-01-01

    Bantu speech communities expanded over large parts of sub-Saharan Africa within the last 4000–5000 years, reaching different parts of southern Africa 1200–2000 years ago. The Bantu languages subdivide in several major branches, with languages belonging to the Eastern and Western Bantu branches spreading over large parts of Central, Eastern, and Southern Africa. There is still debate whether this linguistic divide is correlated with a genetic distinction between Eastern and Western Bantu speakers. During their expansion, Bantu speakers would have come into contact with diverse local populations, such as the Khoisan hunter-gatherers and pastoralists of southern Africa, with whom they may have intermarried. In this study, we analyze complete mtDNA genome sequences from over 900 Bantu-speaking individuals from Angola, Zambia, Namibia, and Botswana to investigate the demographic processes at play during the last stages of the Bantu expansion. Our results show that most of these Bantu-speaking populations are genetically very homogenous, with no genetic division between speakers of Eastern and Western Bantu languages. Most of the mtDNA diversity in our dataset is due to different degrees of admixture with autochthonous populations. Only the pastoralist Himba and Herero stand out due to high frequencies of particular L3f and L3d lineages; the latter are also found in the neighboring Damara, who speak a Khoisan language and were foragers and small-stock herders. In contrast, the close cultural and linguistic relatives of the Herero and Himba, the Kuvale, are genetically similar to other Bantu-speakers. Nevertheless, as demonstrated by resampling tests, the genetic divergence of Herero, Himba, and Kuvale is compatible with a common shared ancestry with high levels of drift, while the similarity of the Herero, Himba, and Damara probably reflects admixture, as also suggested by linguistic analyses. PMID:24901532

  10. Changes in Holocene to LGM water mass stratification near Southern Africa inferred from Nd isotopes

    NASA Astrophysics Data System (ADS)

    Jones, K. M.; Goldstein, S. L.; Hemming, S. R.; Hall, I. R.; Zahn, R.

    2009-12-01

    Global thermohaline circulation (THC) is an important component of the climate system that initiates or amplifies abrupt climate change. A major driver of THC is the formation of North Atlantic Deep Water (NADW), which is sandwiched by northward flowing Southern Ocean water masses as it is advected southward. An important exit route of NADW out of the South Atlantic is through flow around the southern tip of Africa, which makes the South African Margin an excellent location to investigate changes in THC and water mass stratification through time. We measured the Nd isotopes of modern seawater from three depth profiles collected along the South African Margin, which were collected on RSS Charles Darwin Cruise 154. All seawater profiles show a similar pattern with higher ɛNd values at intermediate depths (ɛNd ~ -9.5 at 600-1200m), lower values for the core of NADW (ɛNd ~ -11.5 at 2000-3500m), and higher values in the deepest waters sampled (ɛNd -9.8 at 4150m). This pattern is consistent with conservative mixing of major North Atlantic and Southern Ocean end-member water masses and is not consistent with inputs from, or exchange with margin sediments, for most depths. We also measured the Nd isotopes of multiple sedimentary archives in proximal Holocene coretop sediments collected from depths spanning intermediate to deep/bottom waters. The Nd isotopes of a fish tooth, several foram coating leachates, and multiple bulk sediment Fe-Mn leachates display the same pattern as the local seawater. We had no seawater for comparison with our deepest core (VM19-224; depth ~ 4600m), but the eNd value from it (ɛNd = -8.4) is consistent with Antarctic Bottom Water (ɛNd ~ -8.5). These results suggest: (1) that Nd isotopes of seawater in the region behave conservatively; (2) that the local margin sediments faithfully record the Nd isotope composition of the waters they are bathed in and (3) this “ground-truthing” implies that it is valid to use Nd isotopes as a circulation

  11. Maritime and Underwater Cultural Heritage in South Africa: The Development of Relevant Management Strategies in the Historical Maritime Context of the Southern Tip of Africa

    NASA Astrophysics Data System (ADS)

    Sharfman, Jonathan; Boshoff, Jaco; Parthesius, Robert

    2012-10-01

    South Africans have a long association with water. It has provided a source of food, a medium for trade and a catalyst for migration and development. The country's geographical position as a crossroads of maritime trade between Europe and the East means that its history is inextricably linked to the history of the rest of the world. The result is a multi-faceted representation of sites, objects and mythologies related to water and maritime heritage that reflect not only local historical and social development, but global cultural change as well. Given the importance of South Africa's underwater cultural heritage (UCH), managers have grappled with management principles, ethics and theoretical models in an effort to produce and enforce heritage legislation that is relevant and effective. This paper outlines South Africa's maritime context from 1.5 million years ago until the present, summarises legislative and mitigation developments over the past half century and provides details of current trends in maritime archaeology and UCH management at the southern tip of Africa. Training programmes and public awareness are keys to this strategy to bring UCH and maritime archaeology into the mainstream and counter treasure hunting and looting of this rich, friable resource.

  12. Hydrological drought forecasting and skill assessment for the Limpopo River basin, southern Africa

    NASA Astrophysics Data System (ADS)

    Trambauer, P.; Werner, M.; Winsemius, H. C.; Maskey, S.; Dutra, E.; Uhlenbrook, S.

    2015-04-01

    Ensemble hydrological predictions are normally obtained by forcing hydrological models with ensembles of atmospheric forecasts produced by numerical weather prediction models. To be of practical value to water users, such forecasts should not only be sufficiently skilful, they should also provide information that is relevant to the decisions end users make. The semi-arid Limpopo Basin in southern Africa has experienced severe droughts in the past, resulting in crop failure, economic losses and the need for humanitarian aid. In this paper we address the seasonal prediction of hydrological drought in the Limpopo River basin by testing three proposed forecasting systems (FS) that can provide operational guidance to reservoir operators and water managers at the seasonal timescale. All three FS include a distributed hydrological model of the basin, which is forced with either (i) a global atmospheric model forecast (ECMWF seasonal forecast system - S4), (ii) the commonly applied ensemble streamflow prediction approach (ESP) using resampled historical data, or (iii) a conditional ESP approach (ESPcond) that is conditional on the ENSO (El Niño-Southern Oscillation) signal. We determine the skill of the three systems in predicting streamflow and commonly used drought indices. We also assess the skill in predicting indicators that are meaningful to local end users in the basin. FS_S4 shows moderate skill for all lead times (3, 4, and 5 months) and aggregation periods. FS_ESP also performs better than climatology for the shorter lead times, but with lower skill than FS_S4. FS_ESPcond shows intermediate skill compared to the other two FS, though its skill is shown to be more robust. The skill of FS_ESP and FS_ESPcond is found to decrease rapidly with increasing lead time when compared to FS_S4. The results show that both FS_S4 and FS_ESPcond have good potential for seasonal hydrological drought forecasting in the Limpopo River basin, which is encouraging in the context of

  13. The tectonic frame of the Variscan Alleghanian orogen in Southern Europe and Northern Africa

    NASA Astrophysics Data System (ADS)

    Simancas, J. Fernando; Tahiri, Abdelfatah; Azor, Antonio; Lodeiro, Francisco González; Martínez Poyatos, David J.; El Hadi, Hassan

    2005-04-01

    By confronting different geological and geophysical data, we attempt to reconstruct the Variscan-Alleghanian orogenic belt, with especial emphasis on the links between Iberia, northwest Africa, and northeast America. The northern Iberia transect corresponds to the rifted margin of Gondwana, inverted during the Variscan orogeny and overthrust in its westernmost sector by a pile of allochthonous units, some of them with oceanic affinity and witnessing an orogenic suture. The southern Iberia section reveals two sutures at both boundaries of a terrane closely tied to Gondwana, namely the Ossa-Morena Zone. The southern boundary of this zone (i.e., the contact with the South Portuguese Zone) is enhanced by amphibolites with oceanic affinity and probably represents the suture of the Rheic Ocean. The Moroccan Variscides can be divided into: (i) a western external zone, namely the Coastal Block and the Central Massif; (ii) an internal zone, namely the Eastern Meseta; (iii) an eastern external zone represented in the Anti Atlas region; and (iv) the African cratonic foreland. Since neither ophiolites nor eclogites crop out along this transect of the orogen, we consider it to be an incomplete transect, lacking the main suture zone (Rheic Ocean). Stratigraphic and faunal affinities between the Moroccan Meseta, on the one hand, and the Central Iberian, Western Asturian-Leonese, and Cantabrian zones of Iberia, on the other hand, suggest that they may well have been part of a common pre-orogenic domain at the margin of Gondwana. On the contrary, there are no counterparts in Morocco for the Ossa-Morena Zone. Thus, the northern Iberia palaeogeographic zones would prolong in the Moroccan Meseta through an eastward arcuate structure, while the suture of the Rheic Ocean would do so offshore Morocco. In our reconstruction, an Avalonian spur (Grand Banks indentor), which included the Caledonian Sehoul block in northern Morocco and the crust of the South Portuguese Zone in SW Iberia

  14. Nitrogen deposition in a southern hemisphere biodiversity hotspot within and surrounding Cape Town, South Africa

    NASA Astrophysics Data System (ADS)

    Angstmann, J. L.; Hall, S.; February, E.; West, A. G.; Allsopp, N.; Bond, W.

    2011-12-01

    Anthropogenic nitrogen (N) emissions have increased dramatically since the agricultural and industrial revolutions leading to N deposition in the northern hemisphere that is estimated to be an order of magnitude greater than preindustrial fluxes. N deposition rates of 5-15 kg N ha-1 yr-1 in Europe and N. America decrease plant species diversity, increase invasive species, and lead to eutrophication of surface waters. The southern hemisphere is home to over 50% of the world's biodiversity hotspots, including the 90,000 km2 Cape Floristic Region which houses 9,030 vascular plant species, 69% of which are endemic. However, to date, N deposition rates in the southern hemisphere are highly uncertain, with global models of N deposition based upon sparse datasets at best. Many terrestrial systems, such as fynbos shrublands, are adapted to low N availability and exhibit high species diversity and endemism, rendering them susceptible to ecological changes from N deposition. In this research, we quantified the spatial and temporal distribution of wet and dry N deposition across 30 protected fynbos ecosystems within the urban airshed of Cape Town, South Africa. We predicted that 1) total inorganic N deposition varies predictably along the urban-rural gradient (highest near the city centre), 2) N deposition varies seasonally, with higher fluxes in the winter months when atmospheric stability causes a build-up of N gases in and around the city, and 3) total inorganic N deposition will exceed the critical load of 10-15 kg N ha-1 yr-1 for Mediterranean shrublands, past which negative ecosystem effects have been shown to occur. Estimates of N deposition based on NO2 concentrations within the city suggest that total N deposition ranges from 8-13 kg N ha-1 yr-1 . However, we show that N deposition measured by ion-exchange resin collectors is far less than expected, averaging less than 2 kg N ha-1 yr-1 (range 0.5 - 5.5 kg N ha-1 yr-1 ), and is is dominated by NO3-, suggesting

  15. Vegetation Dynamics in Response to Interannual Rainfall Variability in Southern Africa

    NASA Astrophysics Data System (ADS)

    Scanlon, Todd; Caylor, Kelly; Saha, Michael; D'Odorico, Paolo

    2013-04-01

    In the Kalahari region of southern Africa, vegetation cover is highly sensitive to interannual variability in rainfall, a property that is detectable at the regional scale through the use of remote sensing. The disparate sensitivities of the dominant functional forms of the savanna vegetation (i.e., trees and grasses) to rainfall provide a means by which to disaggregate the overall vegetation cover into these functional forms. Through the application of a land surface hydrological model, the dynamical nature of the savanna vegetation is shown to be essential for closing the hydrological budget such that losses from the base of the root zone are minimal. We show that vegetation assemblages comprised of tree cover (which is influenced by mean annual rainfall) and grass cover (which dynamically responds to interannual variability in rainfall) is ideal suited for maximizing use of a fluctuating, limiting resource (i.e., water) in this semi-arid environment. The ability of vegetation to optimally use water is explored through the application of a single metric, stress-weighted plant water uptake, which represents a trade-off between maximizing water use while minimizing water stress. Finally, like many arid and semi-arid regions of the world, the Kalahari seems to be experiencing "greening" over recent decades, at least according to temporal trends in AVHRR-based vegetation indices. We combine MODIS-based Enhanced Vegetation Index (EVI) data with a Tropical Rainfall Measuring Mission (TRMM) product to evaluate such trends in the Kalahari region. In particular, we rely upon an analysis of the sensitivity of EVI to interannual variability in rainfall as a means to determine if there have been any detectable shifts in tree/grass cover composition in the Kalahari associated with this apparent greening.

  16. Assessing the skill of seasonal forecasting of streamflow and drought in the Limpopo basin, Southern Africa

    NASA Astrophysics Data System (ADS)

    Werner, M.; Trambauer, P.; Winsemius, H.; Maskey, S.; Dutra, E. N.; Pappenberger, F.

    2014-12-01

    The semi-arid Limpopo Basin in Southern Africa experiences frequent droughts, leading to shortfall of water resources available to irrigation, drinking water supply and environmental flow requirements. In this paper we explore three approaches to seasonal forecasting streamflow and derived drought indices in the basin. The first applies the ECMWF seasonal forecast system (S4), an operational global atmospheric model that provides seasonal ensemble forecast with a lead time of six months. We apply a 30 year hindcast set available for S4 in forcing a 0.05O distributed hydrological model for the basin. The second approach uses the Ensemble Streamflow Prediction (ESP) method. This develops a forecast ensemble of six months lead time based on resampling historic meteorological data over the basin, and we again use this ensemble to force the hydrological model. The third approach again applies the ESP method, but we now use the ENSO index to condition the sampling probabilities. We focus on comparing forecast skill over the wet season which is the most relevant to water users in the basin. Comparison of the skill of the three forecasting approaches in forecasting drought indices and streamflow shows that S4 is moderately skilful at the lead times up to 3-5 months. The ESP forecasts are skilful when compared to climatology, but only for the short lead times, and the skill decays rapidly with lead time. Forecasts based on the conditional ESP ensemble have improved skill when compared to ESP, though S4 forecasts remain superior. Through exploring drought indices that are used by reservoir operators in determining curtailments to water users we show how the forecasts can be meaningful to reservoir operators and irrigators in the basin.

  17. Hydrological drought forecasting and skill assessment for the Limpopo river basin, Southern Africa

    NASA Astrophysics Data System (ADS)

    Trambauer, P.; Werner, M.; Winsemius, H. C.; Maskey, S.; Dutra, E.; Uhlenbrook, S.

    2014-08-01

    Ensemble hydrological predictions are normally obtained by forcing hydrological models with ensembles of atmospheric forecasts produced by Numerical weather prediction models. To be of practical value to water users, such forecasts should not only be sufficiently skilful, they should also provide information that is relevant to the decisions end users make. The semi-arid Limpopo basin in Southern Africa has experienced severe droughts in the past, resulting in crop failures, high economic losses and the need for humanitarian aid. In this paper we address the seasonal prediction of hydrological drought for the Limpopo river basin by testing three proposed forecasting systems (FS) that can provide operational guidance to dam operators and water managers within the basin at the seasonal time scale. All three FS include a distributed hydrological model of the basin, and are forced with either (i) a global atmospheric model forecast (ECMWF seasonal forecast system - S4), (ii) the commonly applied Ensemble Streamflow Prediction approach (ESP) using resampled historical data, or (iii) a conditional ESP approach (ESPcond), which is conditional on the ENSO signal. We determine the skill of the three systems in predicting drought indices and streamflow. We also assess the skill of the model in predicting indicators that are meaningful to the local end users in the basin. FS_S4 shows moderate skill for all lead times (3, 4, and 5 months) and aggregation periods. FS_ESP also performs better than climatology for the shorter lead times, but with a lower skill than FS_S4. FS_ESPcond shows skill in between the other two FS, though its skill is shown to be more robust. The skills of FS_ESP and FS_ESPcond reduce rapidly with increasing lead time. Both FS_S4 and FS_ESPcond show good potential for seasonal hydrological drought forecasting in the Limpopo river basin, which is encouraging in the context of providing better operational guidance to water users.

  18. "Candidatus Borrelia kalaharica" Detected from a Febrile Traveller Returning to Germany from Vacation in Southern Africa

    PubMed Central

    Wächtler, Martin; Margos, Gabriele; Ruske, Sabine; Jung, Jette; Löscher, Thomas; Wendtner, Clemens; Wieser, Andreas

    2016-01-01

    A 26 year-old female patient presented to the Tropical Medicine outpatient unit of the Ludwig Maximilians-University in Munich with febrile illness after returning from Southern Africa, where she contracted a bite by a large mite-like arthropod, most likely a soft-tick. Spirochetes were detected in Giemsa stained blood smears and treatment was started with doxycycline for suspected tick-borne relapsing fever. The patient eventually recovered after developing a slight Jarisch-Herxheimer reaction during therapy. PCR reactions performed from EDTA-blood revealed a 16S rRNA sequence with 99.4% similarity to both, Borrelia duttonii, and B. parkeri. Further sequences obtained from the flagellin gene (flaB) demonstrated genetic distances of 0.066 and 0.097 to B. parkeri and B. duttonii, respectively. Fragments of the uvrA gene revealed genetic distance of 0.086 to B. hermsii in genetic analysis and only distant relations with classic Old World relapsing fever species. This revealed the presence of a novel species of tick-borne relapsing fever spirochetes that we propose to name “Candidatus Borrelia kalaharica”, as it was contracted from an arthropod bite in the Kalahari Desert belonging to both, Botswana and Namibia, a region where to our knowledge no relapsing fever has been described so far. Interestingly, the novel species shows more homology to New World relapsing fever Borrelia such as B. parkeri or B. hermsii than to known Old World species such as B. duttonii or B. crocidurae. PMID:27031729

  19. Genotypic Diversity Is Associated with Clinical Outcome and Phenotype in Cryptococcal Meningitis across Southern Africa

    PubMed Central

    Beale, Mathew A.; Sabiiti, Wilber; Robertson, Emma J.; Fuentes-Cabrejo, Karen M.; O’Hanlon, Simon J.; Jarvis, Joseph N.; Loyse, Angela; Meintjes, Graeme; Harrison, Thomas S.; May, Robin C.; Fisher, Matthew C.; Bicanic, Tihana

    2015-01-01

    Cryptococcal meningitis is a major cause of mortality throughout the developing world, yet little is known about the genetic markers underlying Cryptococcal virulence and patient outcome. We studied a cohort of 230 Cryptococcus neoformans (Cn) isolates from HIV-positive South African clinical trial patients with detailed clinical follow-up using multi-locus sequence typing and in vitro phenotypic virulence assays, correlating these data with clinical and fungal markers of disease in the patient. South African Cn displayed high levels of genetic diversity and locus variability compared to globally distributed types, and we identified 50 sequence types grouped within the main molecular types VNI, VNII and VNB, with 72% of isolates typed into one of seven 'high frequency' sequence types. Spatial analysis of patients’ cryptococcal genotype was not shown to be clustered geographically, which might argue against recent local acquisition and in favour of reactivation of latent infection. Through comparison of MLST genotyping data with clinical parameters, we found a relationship between genetic lineage and clinical outcome, with patients infected with the VNB lineage having significantly worse survival (n=8, HR 3.35, CI 1.51-7.20, p=0.003), and this was maintained even after adjustment for known prognostic indicators and treatment regimen. Comparison of fungal genotype with in vitro phenotype (phagocytosis, laccase activity and CSF survival) performed on a subset of 89 isolates revealed evidence of lineage-associated virulence phenotype, with the VNII lineage displaying increased laccase activity (p=0.001) and ex vivo CSF survival (p=0.0001). These findings show that Cryptococcus neoformans is a phenotypically heterogeneous pathogen, and that lineage plays an important role in cryptococcal virulence during human infection. Furthermore, a detailed understanding of the genetic diversity in Southern Africa will support further investigation into how genetic diversity is

  20. Oil and gas developments in central and southern Africa in 1983

    SciTech Connect

    McGrew, H.J.

    1984-10-01

    All exploratory activity in central and southern Africa decreased in 1983, reflecting world economic conditions and excess productive capacity. Seismic activity has declined sharply from its peak year of 1981. Land operations suffered the greatest drop in 1983, whereas party-months of marine work increased slightly. 3-D recording continued to be used but at a reduced rate compared with 1982. Large aeromagnetic surveys were made in several countries; however, the coverage was less than in 1982. Gravity continues to be used to supplement other geophysical work, but other exploratory techniques are being used infrequently. Total wells drilled dropped from 464 in 1982 to 387 in 1983. Most of the decline was in exploratory drilling, which dropped from 132 to 86 wells. This was reflected in the number of discoveries, which decreased from 48 to 27 while the success rate continued about the same. Development drilling continued at a high level in Cameroon and Congo, whereas in Nigeria the emphasis shifted to the drilling of appraisal wells. In all, 2,937,708 ft (895,643 m) of hole was drilled, a decrease of about 20% from 1982. Oil production of 673,075,667 bbl in 1983 was an increase of 1.7% over 1982's production, bringing cumulative production to over 12 billion bbl. Marked increases in production were recorded in Cabinda, Ivory Coast, and Congo. Production from Nigerian fields continued to dominate this part of the world as they contributed about 67% of the annual production and 75% of the cumulative production. 44 figures, 15 tables.

  1. Southern Africa Regional Office of Astronomy for Development: A New Hub for Astronomy for Development

    NASA Astrophysics Data System (ADS)

    Siseho Mutondo, Moola

    2015-08-01

    A new Astronomy for Development hub needs innovative tools and programs. SAROAD is developing exciting tools integrating Raspberry Pi® technology to bring cost-effective astronomy content to learning centres. SAROAD would also like to report achievements in realising the IAU's strategic plan. In order to manage, evaluate and coordinate regional IAU capacity building programmes, including the recruitment and mobilisation of volunteers, SAROAD has built an intranet that is accessible to regional members upon request. Using this resource, regional members can see and participate in regional activities. This resource also forms the foundation for closer collaboration between SAROAD member countries. SAROAD has commenced with projects in the three Task Force areas of Universities and Research, Children and Schools and Public Outreach. Under the three Task Force areas, a total of seven projects have commenced in Zambia. A further two projects involve the collaboration of Zambia and other regional member countries in order to foster engagement with important regional astronomy facilities (e.g. SKA). SAROAD has identified the IAU’s International Year of Light and a starting point for offering regional support for IAU-endorsed global activities. SAROAD has set up a hub dedicated to regional events and activities about the International Year of Light. SAROAD has a database of regional authorities to enable contact with the region's decision makers and experts. SAROAD will hold an annual event which brings forum for astronomy for development. The creation of the database and the SAROAD Road show is a first step towards this goal. The SAROAD website has helped to advertise upcoming events for astronomy development and education; it is used to provide advice, guidance and information for astronomers in all countries in the Southern Africa. Fundraising is the primary goal for SAROAD in 2015 towards financial self-sufficiency by 2020. We report on the methods that work best

  2. Genetic Diversity of White Sharks, Carcharodon carcharias, in the Northwest Atlantic and Southern Africa.

    PubMed

    O'Leary, Shannon J; Feldheim, Kevin A; Fields, Andrew T; Natanson, Lisa J; Wintner, Sabine; Hussey, Nigel; Shivji, Mahmood S; Chapman, Demian D

    2015-01-01

    The white shark, Carcharodon carcharias, is both one of the largest apex predators in the world and among the most heavily protected marine fish. Population genetic diversity is in part shaped by recent demographic history and can thus provide information complementary to more traditional population assessments, which are difficult to obtain for white sharks and have at times been controversial. Here, we use the mitochondrial control region and 14 nuclear-encoded microsatellite loci to assess white shark genetic diversity in 2 regions: the Northwest Atlantic (NWA, N = 35) and southern Africa (SA, N = 131). We find that these 2 regions harbor genetically distinct white shark populations (Φ ST = 0.10, P < 0.00001; microsatellite F ST = 0.1057, P < 0.021). M-ratios were low and indicative of a genetic bottleneck in the NWA (M-ratio = 0.71, P < 0.004) but not SA (M-ratio = 0.85, P = 0.39). This is consistent with other evidence showing a steep population decline occurring in the mid to late 20th century in the NWA, whereas the SA population appears to have been relatively stable. Estimates of effective population size ranged from 22.6 to 66.3 (NWA) and 188 to 1998.3 (SA) and evidence of inbreeding was found (primarily in NWA). Overall, our findings indicate that white population dynamics within NWA and SA are determined more by intrinsic reproduction than immigration and there is genetic evidence of a population decline in the NWA, further justifying the strong domestic protective measures that have been taken for this species in this region. Our study also highlights how assessment of genetic diversity can complement other sources of information to better understand the status of threatened marine fish populations. PMID:25762777

  3. 'Issues of equity are also issues of rights': Lessons from experiences in Southern Africa

    PubMed Central

    London, Leslie

    2007-01-01

    Background Human rights approaches to health have been criticized as antithetical to equity, principally because they are seen to prioritise rights of individuals at the expense of the interests of groups, a core tenet of public health. The objective of this study was to identify how human rights approaches can promote health equity. Methods The Network on Equity in Health in Southern Africa undertook an exploration of three regional case studies – antiretroviral access, patient rights charters and civic organization for health. A combination of archival reviews and stakeholder interviews were complemented with a literature review to provide a theoretical framework for the empirical evidence. Results Critical success factors for equity are the importance of rights approaches addressing the full spectrum from civil and political, through to socio-economic rights, as well as the need to locate rights in a group context. Human rights approaches succeed in achieving health equity when coupled with community engagement in ways that reinforce community capacity, particularly when strengthening the collective agency of its most vulnerable groups. Additionally, human rights approaches provide opportunities for mobilising resources outside the health sector, and must aim to address the public-private divide at local, national and international levels. Conclusion Where it is clear that rights approaches are predicated upon understanding the need to prioritize vulnerable groups and where the way rights are operationalised recognizes the role of agency on the part of those most affected in realising their socio-economic rights, human rights approaches appear to offer powerful tools to support social justice and health equity. PMID:17257421

  4. Alpine turf exfoliation pans in Lesotho, southern Africa: Climate-process-morphological linkages

    NASA Astrophysics Data System (ADS)

    Grab, Stefan W.

    2010-01-01

    Although alpine pans have been reported from a variety of mountain regions, these have received limited research attention and are thus amongst the least known of 'closed basins'. This study investigates macro- and fine-scale morphological attributes and the process dynamics of alpine turf exfoliation pans in the high Drakensberg of Lesotho, southern Africa. Climate data (temperature, precipitation and wind) are used to better ascertain climate-surface process linkages and how these may be associated with the observed morphological phenomena. Thirty pans were assessed for both macro- and fine-scale aspect-controlled morphological attributes. During 2005, Tinytag™ temperature loggers recorded ground temperatures on various pan riser aspects to establish the potential for cryogenic activity. Similarly, wind speed and direction data from 2001 were used to identify the potential role of wind as an erosion and transportation mechanism. The number and total weight of detached turf clumps accumulated at the base of various pan riser aspects were determined in July 1999, September 2001 and September 2004. It is suggested that the pans originated through initial turf disruption by animal trampling and turf burning, followed by the cryogenic up-heave of sediments. The pans typically elongate towards the southeast as they enlarge, demonstrate most active erosion on eastern and southeastern riser aspects, and host seasonal micro-echo and micro-climbing dunes along such riser aspects. It is concluded that an annual cyclic (seasonal) pattern of contemporary climate-driven geomorphic processes, dominated by strong northwesterly winds, control the fine-scale morphological evolution of alpine turf exfoliation pans in the Lesotho highlands.

  5. Participatory planning in river catchments, an innovative toolkit tested in Southern Africa and North West England.

    PubMed

    Tippett, J

    2005-01-01

    The European Union Water Framework Directive (WFD) offers an unparalleled opportunity for improving river basin management. Active participation is essential for its delivery. "End-of-pipe" solutions will not deliver the improvements needed to achieve its ambitious goals. This research tested DesignWays, a toolkit for participatory planning, as a mechanism for maximizing the long-term social and environmental benefits of such stakeholder and community participation. It examined the emerging role of "planning for sustainability" in the context of river catchments. Sustainable management of water requires integration, and recognition of interconnections between systems at different levels of scale. This is an endeavour in which systems thinking provides useful tools. The development of DesignWays was a conscious attempt to embed 'new paradigm' living systems metaphors into a practical planning tool. This paper begins with a description of DesignWays and its development in Southern Africa. An outline of the context of the action research in North-West England is followed by a description of the stages of the process, with highlights of the outcomes. This research had two major outcomes: a contribution to theory through an in-depth exploration of the theoretical basis of participatory, ecologically informed design; and a contribution to practice through investigating DesignWays' potential to meet key challenges of the WFD. This research points to the importance of understanding participatory planning as a societal process, aiming to make the process engaging and meaningful. It has pointed to the need to see participatory planning and education for sustainability as an integrated process. It demonstrated the benefits of an iterative process in which planning at the landscape level of scale informs, and is informed by, work at the site level. It has shown that an approach consistent with a living systems paradigm can contribute to the development of more integrated

  6. "Candidatus Borrelia kalaharica" Detected from a Febrile Traveller Returning to Germany from Vacation in Southern Africa.

    PubMed

    Fingerle, Volker; Pritsch, Michael; Wächtler, Martin; Margos, Gabriele; Ruske, Sabine; Jung, Jette; Löscher, Thomas; Wendtner, Clemens; Wieser, Andreas

    2016-03-01

    A 26 year-old female patient presented to the Tropical Medicine outpatient unit of the Ludwig Maximilians-University in Munich with febrile illness after returning from Southern Africa, where she contracted a bite by a large mite-like arthropod, most likely a soft-tick. Spirochetes were detected in Giemsa stained blood smears and treatment was started with doxycycline for suspected tick-borne relapsing fever. The patient eventually recovered after developing a slight Jarisch-Herxheimer reaction during therapy. PCR reactions performed from EDTA-blood revealed a 16S rRNA sequence with 99.4% similarity to both, Borrelia duttonii, and B. parkeri. Further sequences obtained from the flagellin gene (flaB) demonstrated genetic distances of 0.066 and 0.097 to B. parkeri and B. duttonii, respectively. Fragments of the uvrA gene revealed genetic distance of 0.086 to B. hermsii in genetic analysis and only distant relations with classic Old World relapsing fever species. This revealed the presence of a novel species of tick-borne relapsing fever spirochetes that we propose to name "Candidatus Borrelia kalaharica", as it was contracted from an arthropod bite in the Kalahari Desert belonging to both, Botswana and Namibia, a region where to our knowledge no relapsing fever has been described so far. Interestingly, the novel species shows more homology to New World relapsing fever Borrelia such as B. parkeri or B. hermsii than to known Old World species such as B. duttonii or B. crocidurae. PMID:27031729

  7. Metal Enrichment and Toxicity Levels in Sediments from the Tourist Beaches of Southern Durban, South Africa

    NASA Astrophysics Data System (ADS)

    Chari, S. V.; Vetrimurugan, E.; Jonathan, M. P.; Rodriguez-Espinosa, P. F.

    2014-12-01

    Durban city in South Africa is developing in a fast pace in the field of tourism and thereby needs to be reviewed for the enrichment of metals in tourist beaches. Geochemical studies have been done on nearly 65 beach sediments collected from inter-tidal regions of Amanzi Toti, Isipingo, Bluff, Cutting and southern part of Durban beaches. The study was done in order to unravel the anthropogenic and natural geochemical signals. Total (TTMs) and partially extracted trace metals (PETMs) (As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, Zn) in sediments were evaluated along with organic carbon and carbonates. Evaluation of enrichment of geochemical elements were done using contamination factor (CF), pollution load index (PLI), ecological risk index (RI) and geoaccumulation index (Igeo) to understand the pollution status of the study area and it indicates that As, Cd, Cu, Fe, Mn, Ni, Pb, V and Zn are enriched by two to three folds from the natural background values. Uncontrolled tourism activities have led to increase of certain elements in the Durban beaches. Textural analysis provides the information regarding the dominance of sediments either in sand fraction, mud fraction or gravel. The results indicated that they are dominantly coarse grained except in regions where local river input is observed. Industrial development as well as the mining activities in few locations near the coast has led to increase in the elemental concentrations. Regular monitoring of enrichment levels of trace metals in the sediments is mandatory to assess the beach quality in order to restore them from further enrichment so that the biological system in this region is also preserved. Keywords: Tourism, Beach sediments, Trace metals, contamination indices.

  8. Burns in Malawi

    PubMed Central

    Virich, G.; Lavy, C.B.D.

    2006-01-01

    Summary Objective: To describe burns seen at the largest hospital in Malawi. Methods: In a prospective study conducted at Queen Elizabeth Central Hospital, Blantyre, Malawi, a series of twelve accidental burns was analysed over a four-week period. Results: Hot water was the commonest source of burns (6 out of 12). Open-fire and petroleum lamp accidents were the commonest cause of burns among epileptic patients. Males were affected more than females (male:female ratio = 8:4). Most burns were superficial (11 out of 12). One patient had deep burns requiring grafting. All patients were treated with topical silver sulphadiazine and a combination antibiotic regime. Children aged six yr or under were a major subgroup at risk of suffering burns (7 out of 12) and only one patient was aged over 30 yr. Lack of anti-epileptic medication resulted in potentially avoidable burns in four epileptic patients. Conclusions: There is a need for cheap preventive health promotion measures as well as the provision of simple resources as most burns encountered can be managed effectively by simple measures. PMID:21991045

  9. Cross-Border Cholera Outbreaks in Sub-Saharan Africa, the Mystery behind the Silent Illness: What Needs to Be Done?

    PubMed Central

    Mwesawina, Maurice; Baluku, Yosia; Kanyanda, Setiala S. E.; Orach, Christopher Garimoi

    2016-01-01

    Introduction Cross-border cholera outbreaks are a major public health problem in Sub-Saharan Africa contributing to the high annual reported cholera cases and deaths. These outbreaks affect all categories of people and are challenging to prevent and control. This article describes lessons learnt during the cross-border cholera outbreak control in Eastern and Southern Africa sub-regions using the case of Uganda-DRC and Malawi-Mozambique borders and makes recommendations for future outbreak prevention and control. Materials and Methods We reviewed weekly surveillance data, outbreak response reports and documented experiences on the management of the most recent cross-border cholera outbreaks in Eastern and Southern Africa sub-regions, namely in Uganda and Malawi respectively. Uganda-Democratic Republic of Congo and Malawi-Mozambique borders were selected because the countries sharing these borders reported high cholera disease burden to WHO. Results A total of 603 cross-border cholera cases with 5 deaths were recorded in Malawi and Uganda in 2015. Uganda recorded 118 cases with 2 deaths and CFR of 1.7%. The under-fives and school going children were the most affected age groups contributing 24.2% and 36.4% of all patients seen along Malawi-Mozambique and Uganda-DRC borders, respectively. These outbreaks lasted for over 3 months and spread to new areas leading to 60 cases with 3 deaths, CRF of 5%, and 102 cases 0 deaths in Malawi and Uganda, respectively. Factors contributing to these outbreaks were: poor sanitation and hygiene, use of contaminated water, floods and rampant cross-border movements. The outbreak control efforts mainly involved unilateral measures implemented by only one of the affected countries. Conclusions Cross-border cholera outbreaks contribute to the high annual reported cholera burden in Sub-Saharan Africa yet they remain silent, marginalized and poorly identified by cholera actors (governments and international agencies). The under-fives and the

  10. A first calibration of nonmarine ostracod species for the quantitative estimation of Pleistocene climate change in southern Africa

    NASA Astrophysics Data System (ADS)

    Horne, D. J.; Martens, K.

    2009-04-01

    Although qualitative statements have been made about general climatic conditions in southern Africa during the Pleistocene, there are few quantifiable palaeoclimatic data based on field evidence, especially regarding whether the area was wetter or drier during the Last Glacial Maximum. Such information is critical in validating models of climate change, both in spatial and temporal dimensions. As an essential preliminary step towards palaeoclimate reconstructions using fossil ostracods from cored lake sediment sequences, we have calibrated a training set of living ostracod species' distributions against a modern climate dataset and other available environmental data. The modern ostracod dataset is based on the collections in the Royal Belgian Institute of Natural Sciences in Brussels, which constitutes the most diverse and comprehensive collection of southern African nonmarine ostracods available anywhere in the world. To date, c. 150 nominal species have been described from southern Africa (Martens, 2001) out of c. 450 species in the total Afrotropical area (Martens et al., 2008). Here we discuss the potential value and limitations of the training set for the estimation of past climatic parameters including air temperature (July and January means, maxima and minima, Mean Annual Air Temperature), precipitation, water conductivity and pH. The next step will be to apply the Mutual Ostracod Temperature Range method (Horne, 2007; Horne & Mezquita, 2008) to the palaeoclimatic analysis of fossil ostracod assemblages from sequences recording the Last Glacial Maximum in southern Africa. Ultimately this work will contribute to the development of a glacier-climate modelling project based on evidence of former niche glaciation of the Drakensberg Escarpment. Horne, D. J. 2007. A Mutual Temperature Range method for Quaternary palaeoclimatic analysis using European nonmarine Ostracoda. Quaternary Science Reviews, 26, 1398-1415. Horne, D. J. & Mezquita, F. 2008. Palaeoclimatic

  11. Calibrating a new proxy for Pleistocene climate change in southern Africa: the Mutual Ostracod Temperature Range method

    NASA Astrophysics Data System (ADS)

    Horne, David; Martens, Koen

    2010-05-01

    The Mutual Ostracod Temperature Range (MOTR) method has so far been applied only in the European Pleistocene, where it is proving effective in producing past air temperature range estimates that compare well with those obtained by other proxy methods (Horne, 2007; Horne & Mezquita, 2008; Holmes et al., in press). As an essential preliminary step towards applying the method in southern Africa, we have calibrated a training set of living ostracod species' distributions against a modern climate dataset and other available environmental data. The modern ostracod dataset is based on material held by the Royal Belgian Institute of Natural Sciences in Brussels, which constitutes the most diverse and comprehensive collection of southern African nonmarine ostracods available anywhere in the world. To date, c. 150 nominal species have been described from southern Africa (Martens, 2001) out of c. 450 species in the total Afrotropical area (Martens et al., 2008). We used an edited dataset comprising a total of 2,118 records of ostracod species from 748 localities in southern Africa, ranging in latitude from approximately 17 degrees S to 35 degrees S. We have explored the potential value and limitations of this training set for the estimation of past climatic parameters including mean July, January and annual air temperatures, precipitation, water conductivity and pH. Holmes, J. A., Atkinson, T., Darbyshire, D. P. F., Horne, D. J., Joordens, J., Roberts, M. B., Sinka, K. J. & Whittaker, J. E. (accepted, in press). Middle Pleistocene climate and hydrological environment at the Boxgrove hominin site (West Sussex, UK) from ostracod records. Quaternary Science Reviews, doi:10.1016/j.quascirev.2009.02.024, 1-13. Horne, D. J. 2007. A Mutual Temperature Range method for Quaternary palaeoclimatic analysis using European nonmarine Ostracoda. Quaternary Science Reviews, 26, 1398-1415. Horne, D. J. & Mezquita, F. 2008. Palaeoclimatic applications of large databases: developing and testing

  12. Lessons from the recent rise in use of female sterilization in Malawi.

    PubMed

    Jacobstein, Roy

    2013-03-01

    Although female sterilization is the most widely used modern contraceptive method in the world, most family planning programs in Africa have had difficulty providing it. Malawi, however, despite daunting constraints, has made female sterilization widely and equitably accessible, thereby increasing method choice and helping its citizens better meet their reproductive intentions. Ten percent of currently married Malawian women of reproductive age rely on female sterilization for contraceptive protection, compared with less than 2 percent across Africa, and demand to limit births now exceeds demand to space births. Malawi's female sterilization prevalence surpasses that of some high-resource countries. Key service-delivery factors enabling this achievement include supportive policies, strong public-private partnerships, and mobile services delivered at no cost by dedicated providers. Challenges remain, but Malawi's achievement offers lessons for other countries with low availability of female sterilization and similar resource constraints. PMID:23512875

  13. Integrating interannual climate variability forecasts into weather-indexed crop insurance. The case of Malawi, Kenya and Tanzania

    NASA Astrophysics Data System (ADS)

    Vicarelli, M.; Giannini, A.; Osgood, D.

    2009-12-01

    In this study we explore the potential for re-insurance schemes built on regional climatic forecasts. We focus on micro-insurance contracts indexed on precipitation in 9 villages in Kenya, Tanzania (Eastern Africa) and Malawi (Southern Africa), and analyze the precipitation patterns and payouts resulting from El Niño Southern Oscillation (ENSO). The inability to manage future climate risk represents a “poverty trap” for several African regions. Weather shocks can potentially destabilize not only household, but also entire countries. Governments in drought-prone countries, donors and relief agencies are becoming aware of the importance to develop an ex-ante risk management framework for weather risk. Joint efforts to develop innovative mechanisms to spread and pool risk such as microinsurance and microcredit are currently being designed in several developing countries. While ENSO is an important component in modulating the rainfall regime in tropical Africa, the micro-insurance experiments currently under development to address drought risk among smallholder farmers in this region do not take into account ENSO monitoring or forecasting yet. ENSO forecasts could be integrated in the contracts and reinsurance schemes could be designed at the continental scale taking advantage of the different impact of ENSO on different regions. ENSO is associated to a bipolar precipitation pattern in Southern and Eastern Africa. La Niña years (i.e. Cold ENSO Episodes) are characterized by dry climate in Eastern Africa and wet climate in Southern Africa. During El Niño (or Warm Episode) the precipitation dipole is inverted, and Eastern Africa experiences increased probability for above normal rainfall (Halpert and Ropelewski, 1992, Journal of Climate). Our study represents the first exercise in trying to include ENSO forecasts in micro weather index insurance contract design. We analyzed the contracts payouts with respect to climate variability. In particular (i) we simulated

  14. Palaeoclimatic conditions in the Late Triassic-Early Jurassic of southern Africa: A geochemical assessment of the Elliot Formation

    NASA Astrophysics Data System (ADS)

    Sciscio, Lara; Bordy, Emese M.

    2016-07-01

    The Triassic-Jurassic boundary marks a global faunal turnover event that is generally considered as the third largest of five major biological crises in the Phanerozoic geological record of Earth. Determining the controlling factors of this event and their relative contributions to the biotic turnover associated with it is on-going globally. The Upper Triassic and Lower Jurassic rock record of southern Africa presents a unique opportunity for better constraining how and why the biosphere was affected at this time not only because the succession is richly fossiliferous, but also because it contains important palaeoenvironmental clues. Using mainly sedimentary geochemical proxies (i.e., major, trace and rare earth elements), our study is the first quantitative assessment of the palaeoclimatic conditions during the deposition of the Elliot Formation, a continental red bed succession that straddles the Triassic-Jurassic boundary in southern Africa. Employing clay mineralogy as well as the indices of chemical alteration and compositional variability, our results confirm earlier qualitative sedimentological studies and indicate that the deposition of the Upper Triassic and Lower Jurassic Elliot Formation occurred under increasingly dry environmental conditions that inhibited chemical weathering in this southern part of Pangea. Moreover, the study questions the universal validity of those studies that suggest a sudden increase in humidity for the Lower Jurassic record and supports predictions of long-term global warming after continental flood basalt emplacement.

  15. "Of sheep and men": earliest direct evidence of caprine domestication in southern Africa at Leopard Cave (Erongo, Namibia).

    PubMed

    Pleurdeau, David; Imalwa, Emma; Détroit, Florent; Lesur, Joséphine; Veldman, Anzel; Bahain, Jean-Jacques; Marais, Eugène

    2012-01-01

    The origins of herding practices in southern Africa remain controversial. The first appearance of domesticated caprines in the subcontinent is thought to be c. 2000 years BP; however, the origin of this cultural development is still widely debated. Recent genetic analyses support the long-standing hypothesis of herder migration from the north, while other researchers have argued for a cultural diffusion hypothesis where the spread of herding practices took place without necessarily implicating simultaneous and large population movements. Here we document the Later Stone Age (LSA) site of Leopard Cave (Erongo, Namibia), which contains confirmed caprine remains, from which we infer that domesticates were present in the southern African region as early as the end of the first millennium BC. These remains predate the first evidence of domesticates previously recorded for the subcontinent. This discovery sheds new light on the emergence of herding practices in southern Africa, and also on the possible southward routes used by caprines along the western Atlantic coast. PMID:22808138

  16. “Of Sheep and Men”: Earliest Direct Evidence of Caprine Domestication in Southern Africa at Leopard Cave (Erongo, Namibia)

    PubMed Central

    Pleurdeau, David; Imalwa, Emma; Détroit, Florent; Lesur, Joséphine; Veldman, Anzel; Bahain, Jean-Jacques; Marais, Eugène

    2012-01-01

    The origins of herding practices in southern Africa remain controversial. The first appearance of domesticated caprines in the subcontinent is thought to be c. 2000 years BP; however, the origin of this cultural development is still widely debated. Recent genetic analyses support the long-standing hypothesis of herder migration from the north, while other researchers have argued for a cultural diffusion hypothesis where the spread of herding practices took place without necessarily implicating simultaneous and large population movements. Here we document the Later Stone Age (LSA) site of Leopard Cave (Erongo, Namibia), which contains confirmed caprine remains, from which we infer that domesticates were present in the southern African region as early as the end of the first millennium BC. These remains predate the first evidence of domesticates previously recorded for the subcontinent. This discovery sheds new light on the emergence of herding practices in southern Africa, and also on the possible southward routes used by caprines along the western Atlantic coast. PMID:22808138

  17. Mantle Anisotropy, Collisional Rifts and the Magmatic Evolution of Southern Africa: Old (Mantle) Fabric Never Dies.

    NASA Astrophysics Data System (ADS)

    Silver, P. G.; Fouch, M.; Gao, S.; Schmitz, M.

    2003-12-01

    The observed seismic anisotropy of the southern African mantle, made possible by data from the Southern African Seismic Experiment, provides important constraints on modes of mantle deformation beneath this ancient continent. We find that the mantle anisotropy is dominated by deformational events in Archean times occurring within the lithosphere, and can thus be used to assess the mantle's role in the tectonic evolution of this region. The pattern of mantle anisotropy derived from shear wave splitting observations reveals two noteworthy characteristics. First, there is a spatially continuous arc of mantle anisotropy extending from the western Kaapvaal and Zimbabwe Cratons to the northeastern Kaapvaal. All along the arc, the splitting fast polarization direction, φ , is subparallel to the trend of the arc. Given the crust/mantle chronology associated with these regions, the anisotropy likely represents deformation that occurred at ca. 2.9 to 2.7 Ga during collisional accretion of both the western Kimberley and northern Pietersburg blocks onto the ca. 3.2 Ga eastern shield of the Kaapvaal, with accretion on the northern ramparts of the Kaapvaal ultimately culminating in the Neo-Archean Limpopo orogen. Second, there is mantle anisotropy closely associated with the Great Dyke with values of φ parallel to the Dyke, just north of and distinct from this arc of anisotropy. We present evidence that the mantle fabric that generates seismic anisotropy also constitutes preexisting structure in the mantle that is subsequently reactivated, much like the more commonly cited reactivation of crustal structures. In particular, we argue that the Neo-Archean collision imparted a mechanical anisotropy to the mantle that controlled the subsequent magmatic history of cratonic southern Africa (old fabric never dies!). Study of mechanical anisotropy of olivine aggregates suggests that failure is most likely parallel to the olivine b-plane, which for transcurrent deformation is a vertical

  18. Sexual abuse in Malawi: patterns of disclosure.

    PubMed

    Mason, Carole; Kennedy, Neil

    2014-01-01

    Potential human immunodeficiency virus transmission makes prompt disclosure of child sexual abuse in Africa critical. The pattern of disclosure of 133 children presenting to the largest hospital in Malawi were analyzed. Eighty percent presented early enough for effective use of HIV postexposure prophylaxis. Seventy-five percent of children made a disclosure of child sexual abuse; 29% spontaneously and 47% after prompting. Disclosures were most commonly made to a parent, and age did not affect the pattern of disclosure. The number of children reporting child sexual abuse is increasing, possibly because of increasing awareness, availability of services, and fear of HIV. Although prompt disclosure rates were relatively high, facilitating easier disclosure of child sexual abuse by a free telephone help-line and better training of teachers may be helpful. PMID:24641596

  19. HIV/AIDS reduces the relevance of the principle of individual medical confidentiality among the Bantu people of Southern Africa.

    PubMed

    Ndebele, Paul; Mfutso-Bengo, Joseph; Masiye, Francis

    2008-01-01

    The principle of individual medical confidentiality is one of the moral principles that Africa inherited unquestioningly from the West as part of Western medicine. The HIV/AIDS pandemic in Southern Africa has reduced the relevance of the principle of individual medical confidentiality. Individual medical confidentiality has especially presented challenges for practitioners among the Bantu communities that are well known for their social inter-connectedness and the way they value their extended family relations. Individual confidentiality has raised several unforeseen problems for persons living with HIV/AIDS, ranging from stigma and isolation to feelings of dejection as it drives them away from their families as a way of trying to keep information about their conditions confidential. The involvement of family members in treatment decisions is in line with the philosophy of Ubuntu and serves to respect patients' and families' autonomy while at the same time benefiting the individual patient. PMID:19048391

  20. Foraging ranges of immature African white-backed vultures (Gyps africanus) and their use of protected areas in southern Africa.

    PubMed

    Phipps, W Louis; Willis, Stephen G; Wolter, Kerri; Naidoo, Vinny

    2013-01-01

    Vultures in the Gyps genus are declining globally. Multiple threats related to human activity have caused widespread declines of vulture populations in Africa, especially outside protected areas. Addressing such threats requires the estimation of foraging ranges yet such estimates are lacking, even for widespread (but declining) species such as the African white-backed vulture (Gyps africanus). We tracked six immature African white-backed vultures in South Africa using GPS-GSM units to study their movement patterns, their use of protected areas and the time they spent in the vicinity of supplementary feeding sites. All individuals foraged widely; their combined foraging ranges extended into six countries in southern Africa (mean (± SE) minimum convex polygon area =269,103±197,187 km(2)) and three of the vultures travelled more than 900 km from the capture site. All six vultures spent the majority of their tracking periods outside protected areas. South African protected areas were very rarely visited whereas protected areas in northern Botswana and Zimbabwe were used more frequently. Two of the vultures visited supplementary feeding sites regularly, with consequent reduced ranging behaviour, suggesting that individuals could alter their foraging behaviour in response to such sites. We show that immature African white-backed vultures are capable of travelling throughout southern Africa, yet use protected areas to only a limited extent, making them susceptible to the full range of threats in the region. The standard approach of designating protected areas to conserve species is unlikely to ensure the protection of such wide-ranging species against threats in the wider landscape. PMID:23382824

  1. Foraging Ranges of Immature African White-Backed Vultures (Gyps africanus) and Their Use of Protected Areas in Southern Africa

    PubMed Central

    Phipps, W. Louis; Willis, Stephen G.; Wolter, Kerri; Naidoo, Vinny

    2013-01-01

    Vultures in the Gyps genus are declining globally. Multiple threats related to human activity have caused widespread declines of vulture populations in Africa, especially outside protected areas. Addressing such threats requires the estimation of foraging ranges yet such estimates are lacking, even for widespread (but declining) species such as the African white-backed vulture (Gyps africanus). We tracked six immature African white-backed vultures in South Africa using GPS-GSM units to study their movement patterns, their use of protected areas and the time they spent in the vicinity of supplementary feeding sites. All individuals foraged widely; their combined foraging ranges extended into six countries in southern Africa (mean (± SE) minimum convex polygon area  = 269,103±197,187 km2) and three of the vultures travelled more than 900 km from the capture site. All six vultures spent the majority of their tracking periods outside protected areas. South African protected areas were very rarely visited whereas protected areas in northern Botswana and Zimbabwe were used more frequently. Two of the vultures visited supplementary feeding sites regularly, with consequent reduced ranging behaviour, suggesting that individuals could alter their foraging behaviour in response to such sites. We show that immature African white-backed vultures are capable of travelling throughout southern Africa, yet use protected areas to only a limited extent, making them susceptible to the full range of threats in the region. The standard approach of designating protected areas to conserve species is unlikely to ensure the protection of such wide-ranging species against threats in the wider landscape. PMID:23382824

  2. The Relative Influence of Competition and Prey Defenses on the Phenotypic Structure of Insectivorous Bat Ensembles in Southern Africa

    PubMed Central

    Schoeman, M. Corrie; Jacobs, David S.

    2008-01-01

    Deterministic filters such as competition and prey defences should have a strong influence on the community structure of animals such as insectivorous bats that have life histories characterized by low fecundity, low predation risk, long life expectancy, and stable populations. We investigated the relative influence of these two deterministic filters on the phenotypic structure of insectivorous bat ensembles in southern Africa. We used null models to simulate the random phenotypic patterns expected in the absence of competition or prey defences and analysed the deviations of the observed phenotypic pattern from these expected random patterns. The phenotypic structure at local scales exhibited non-random patterns consistent with both competition and prey defense hypotheses. There was evidence that competition influenced body size distribution across ensembles. Competition also influenced wing and echolocation patterns in ensembles and in functional foraging groups with high species richness or abundance. At the same time, prey defense filters influenced echolocation patterns in two species-poor ensembles. Non-random patterns remained evident even after we removed the influence of body size from wing morphology and echolocation parameters taking phylogeny into account. However, abiotic filters such as geographic distribution ranges of small and large-bodied species, extinction risk, and the physics of flight and sound probably also interacted with biotic filters at local and/or regional scales to influence the community structure of sympatric bats in southern Africa. Future studies should investigate alternative parameters that define bat community structure such as diet and abundance to better determine the influence of competition and prey defences on the structure of insectivorous bat ensembles in southern Africa. PMID:19005563

  3. Integrating indigenous knowledge with conventional science: Enhancing localised climate and weather forecasts in Nessa, Mulanje, Malawi

    NASA Astrophysics Data System (ADS)

    Kalanda-Joshua, Miriam; Ngongondo, Cosmo; Chipeta, Lucy; Mpembeka, F.

    Subsistence rain fed agriculture underpins rural livelihoods in the Sub Saharan Africa. The overdependence on rainfall suggests the need for more reliable climate and weather forecasts to guide farm level decision making. Traditionally, African farmers have used indigenous knowledge (IK) to understand weather and climate patterns and make decisions about crops and farming practices. However, increased rainfall variability in recent years associated with climate change has reduced their confidence in indigenous knowledge, hence reducing their adaptive capacity and increasing their vulnerability to climate change. To address this problem, researchers are advocating the integration of indigenous knowledge into scientific climate forecasts at the local level, where it can be used to enhance the resilience of communities vulnerable to climate change. A study was therefore conducted to establish commonly used IK indicators in weather and climate forecasting and people’s perceptions of climate change and variability in Nessa Village, Southern Malawi. We further compared the people’s perceptions on climate change and variability with empirical evidence from a nearby weather station during 1971-2003 and the major constraints that the people face to fully utilise conventional weather and climate forecasts. Our results show various forms of traditional indicators that have been used to predict weather and climate for generations. These include certain patterns and behaviour of flora and fauna as well as environmental conditions. We further established that the peoples documentation of major climatic events over the years in the area agreed with the empirical evidence from the temperature and rainfall data. Overall, rainfall in the area has reduced since 1971 with increasing temperatures. The people were however of the view that current scientific weather and climate predictions in Malawi were not that useful at village level because they do not incorporate IK.

  4. A Chronological Perspective on the Acheulian and Its Transition to the Middle Stone Age in Southern Africa: The Question of the Fauresmith

    PubMed Central

    Herries, Andy I. R.

    2011-01-01

    An understanding of the age of the Acheulian and the transition to the Middle Stone Age in southern Africa has been hampered by a lack of reliable dates for key sequences in the region. A number of researchers have hypothesised that the Acheulian first occurred simultaneously in southern and eastern Africa at around 1.7-1.6 Ma. A chronological evaluation of the southern African sites suggests that there is currently little firm evidence for the Acheulian occurring before 1.4 Ma in southern Africa. Many researchers have also suggested the occurrence of a transitional industry, the Fauresmith, covering the transition from the Early to Middle Stone Age, but again, the Fauresmith has been poorly defined, documented, and dated. Despite the occurrence of large cutting tools in these Fauresmith assemblages, they appear to include all the technological components characteristic of the MSA. New data from stratified Fauresmith bearing sites in southern Africa suggest this transitional industry maybe as old as 511–435 ka and should represent the beginning of the MSA as a broad entity rather than the terminal phase of the Acheulian. The MSA in this form is a technology associated with archaic H. sapiens and early modern humans in Africa with a trend of greater complexity through time. PMID:21785711

  5. Exploring the correlation between Southern Africa NDVI and Pacific sea surface temperatures: Results for the 1998 maize growing season

    USGS Publications Warehouse

    Verdin, J.; Funk, C.; Klaver, R.; Roberts, D.

    1999-01-01

    Several studies have identified statistically significant correlations between Pacific sea surface temperature anomalies and NDVI anomalies in Southern Africa. The potential predictive value of the relationship was explored for the 1998 maize growing season. Cross-validation techniques suggested a more useful relationship for regions of wet anomaly than for regions of dry anomaly. Observed 1998 NDVI anomaly patterns were consistent with this result. Wet anomalies were observed as expected, but wide areas of expected dry anomalies exhibited average or above-average greeness.

  6. Understanding the Earth Systems of Malawi: Ecological Sustainability, Culture, and Place-Based Education

    ERIC Educational Resources Information Center

    Glasson, George E.; Frykholm, Jeffrey A.; Mhango, Ndalapa A.; Phiri, Absalom D.

    2006-01-01

    The purpose of this 2-year study was to investigate Malawian teacher educators' perspectives and dispositions toward teaching about ecological sustainability issues in Malawi, a developing country in sub-Sahara Africa. This study was embedded in a larger theoretical framework of investigating earth systems science through the understanding of…

  7. Explanations for Child Sexual Abuse Given by Convicted Offenders in Malawi: No Evidence for "HIV Cleansing"

    ERIC Educational Resources Information Center

    Mtibo, Charles; Kennedy, Neil; Umar, Eric

    2011-01-01

    Objective: A commonly cited, but unproven reason given for the rise in reported cases of child sexual abuse in Sub-Saharan Africa is the "HIV cleansing myth"--the belief that an HIV infected individual can be cured by having sex with a child virgin. The purpose of this study was to explore in Malawi the reasons given by convicted sex offenders for…

  8. Implementing Free Primary Education Policy in Malawi and Ghana: Equity and Efficiency Analysis

    ERIC Educational Resources Information Center

    Inoue, Kazuma; Oketch, Moses

    2008-01-01

    Malawi and Ghana are among the numerous Sub-Saharan Africa countries that have in recent years introduced Free Primary Education (FPE) policy as a means to realizing the 2015 Education for All and Millennium Development Goals international targets. The introduction of FPE policy is, however, a huge challenge for any national government that has…

  9. Applying a Reading Program Based on Cognitive Science in Rural Areas of Malawi: Preliminary Results

    ERIC Educational Resources Information Center

    Iyengar, Radhika; Karim, Alia; Chagwira, Florie

    2016-01-01

    Reading fluency is a skill foundational to academic performance, and acquiring this skill in early grades is crucial. Throughout sub-Saharan Africa, reading levels of students are far below grade level, and Malawi is no exception. Research suggests that students, particularly in consistently spelled languages, acquire automaticity most easily by…

  10. A Review of Community Extension Approaches to Innovation for Improved Livelihoods in Ghana, Uganda and Malawi

    ERIC Educational Resources Information Center

    Wellard, Kate; Rafanomezana, Jenny; Nyirenda, Mahara; Okotel, Misaki; Subbey, Vincent

    2013-01-01

    Purpose: Farmer-to-farmer extension offers a potentially low-cost and wide-reach alternative in supporting agricultural innovation. Various approaches are being promoted but information on their impact and sustainability is sparse. This study examines experiences of Self Help Africa and partners in Ghana, Uganda and Malawi. It asks: What is good…

  11. Haplo-block structure of Southern African village chicken populations inferred using genome-wide SNP data.

    PubMed

    Khanyile, K S; Dzomba, E F; Muchadeyi, F C

    2015-01-01

    This study investigated the haplo-block structure, haplotype sharing, and diversity in extensively raised chicken populations of Southern Africa. Two hundred ninety village chickens from Malawi (N = 30), South Africa (N = 132), and Zimbabwe (N = 128) were included in the study, from which 649, 2104, and 2442 haplo-blocks were observed, respectively. The majority of haplo-blocks were smaller than 25 kb in size and only five blocks were more than 2000 kb in size. The low chromosomal coverage of haplo-blocks observed across the genome suggests that multiple recombination events fragmented the ancestral haplo-blocks into smaller sizes. Haplo-block sharing was observed between populations with 2325 haplo-blocks common between Zimbabwe and Malawi and 2689 between South Africa and Zimbabwe. Haplotype sharing allows transferability of genomic tools between these extensively raised chicken populations of Southern Africa. The unique haplo-blocks could have originated from isolated evolution taking place in specific agro-ecological zones. Quantitative trait loci analysis revealed that genes related to body composition were spanned by these haplo-blocks. Body composition traits are important for village chicken populations, which have to harness poor quality feed obtained from the environment to meet their maintenance and production needs. PMID:26505376

  12. Modeling climate change induced hydrological extremes in the Kafue River Basin in Southern Africa

    NASA Astrophysics Data System (ADS)

    Ngongondo, C.; Li, L.; Gong, L.; Xu, C.-Y.

    2012-04-01

    Climate change impact projections in southern Africa suggest significant declines in flows in the major river basins. However, impacts of climate change on hydrological extremes (floods) in the region remain a grey area despite the threat they pose to human life and property. In this study, the impacts of climate change on extreme flows in the upper Kafue River basin, a major tributary of the Zambezi River, were investigated. Catchment hydrography was determined using the Hydro1k at a spatial resolution of 1 km resulting in an approximate registered area of 23,000 km2. The daily global WASMOD-M model was calibrated and validated during 1971 to 2001 with the WATCH Forcing Data (WFD) against observed discharge at Machiya gauging station from the Gridded River Discharge Data Centre(GRDC). Future climate change scenarios for extreme flows were derived by forcing the model with outputs from three GCM's (ECHAM, CMCC3 and IPSL) under the IPCC's SRES A2 and B1 scenarios from 2020 to 2100 at daily timescale. During calibration and validation, the NS coefficient value was above 0.80 and the Pearson correlation coefficient between observed and simulated flows of 0.9, suggesting acceptable model performance. Current and future extremes for each scenario were analyzed using the Peak Over Threshold (POT) analysis fitted to the Generalised Pareto Distribution (GPA), which provided less RMSE values as compared to Annual Maximum Series (AMS) fitted to the Generalized Extreme Value (GEV) distribution. The results show considerable departures from the reference period extremes for most of GCM scenarios considered, with both the A2 and B1 scenarios of the IPSL resulting in higher projected flows as compared to the other two models. On average, floods with return periods T=5,10,50,100,1000 years increased from Q (m3 s-1) = 626.6, 673.9, 767.1, 802.3, 903.7 during the reference period to Q (m3s-1) = 793.5, 873.4, 1046.2, 1119.2, 1364.8 respectively. The approach in our study has a

  13. 'Rumours' and clinical trials: a retrospective examination of a paediatric malnutrition study in Zambia, southern Africa

    PubMed Central

    2010-01-01

    Background Many public health researchers conducting studies in resource-constrained settings have experienced negative 'rumours' about their work; in some cases they have been reported to create serious challenges and derail studies. However, what may appear superficially as 'gossip' or 'rumours' can also be regarded and understood as metaphors which represent local concerns. For researchers unaccustomed to having concerns expressed from participants in this manner, possible reactions can be to be unduly perturbed or conversely dismissive. This paper represents a retrospective examination of a malnutrition study conducted by an international team of researchers in Zambia, Southern Africa. The fears of mothers whose children were involved in the study and some of the concerns which were expressed as rumours are also presented. This paper argues that there is an underlying logic to these anxieties and to dismiss them simply as 'rumours' or 'gossip' would be to overlook the historic and socio-economic factors which have contributed to their production. Methods Qualitative interviews were conducted with the mothers whose children were involved in the study and with the research nurses. Twenty five face-to-face interviews and 2 focus group discussions (FGDs) were conducted with mothers. In addition, face-to-face interviews were conducted with research nurses participating in the trial. Results A prominent anxiety expressed as rumours by the mothers whose children were involved in the study was that recruitment into the trial was an indicator that the child was HIV-infected. Other anxieties included that the trial was a disguise for witchcraft or Satanism and that the children's body parts would be removed and sold. In addition, the liquid, milk-based food given to the children to improve their nutrition was suspected of being insufficiently nutritious, thus worsening their condition. The form which these anxieties took, such as rumours related to the stealing of body

  14. Women, customary law and equality: lessons from research in southern Africa.

    PubMed

    Armstrong, A

    1994-03-01

    The Women and Law in Southern Africa Research Project (WSLA) has concluded, after 6 years of study in Zimbabwe, Zambia, Swaziland, Mozambique, Lesotho, and Botswana, that the deconstruction of customary law rather than an emphasis on the concept of equality represents the most promising strategy for producing justice for women. An historical analysis indicates that customary law was, before colonialism, a family-centered, flexible system of law that favored the negotiation and settlement of disputes rather than a rigid state-centered application of a rule. Traditionally, the unifying value base of customary law was preservation of the family and protection of women and children. Marriage was viewed as a joint partnership rather than a guardian-minor relationship. Polygyny, which today constitutes a source of female subordination, was originally developed to provide the protection of marriage to women at a time when there were not enough men to go around and an unmarried woman was vulnerable. Moreover, under true customary law, family property was the norm and widows remained on the land. The responsiveness of true customary law to changing socioeconomic conditions is illustrated by the newly developed practice of Chiefs in Botswana to allow women to speak and represent themselves in court; another example is the Chief's modification of seduction damages law to stipulate payment directly to the young mother rather than to her parents. After the introduction of colonialism, customary law was reconstructed to serve the political interests of capital; even now, post-independence governments use the law as a tool to oppress women. WLSA research suggests that an emphasis on gender-neutral, equality-based laws and statutes can lead to the further oppression of women. For example, such laws have made unemployed divorced women responsible for the maintenance of their ex-husband, and could be used to promote women, as well as men, having several spouses. Needed instead is an

  15. The health sector gap in the southern Africa crisis in 2002/2003.

    PubMed

    Griekspoor, Andre; Spiegel, Paul; Aldis, William; Harvey, Paul

    2004-12-01

    The southern Africa crisis represents the first widespread emergency in a region with a mature HIV/AIDS epidemic. It provides a steep learning curve for the international humanitarian system in understanding and responding to the complex interactions between the epidemic and the causes and the effects of this crisis. It also provoked much debate about the severity and causes of this emergency, and the appropriateness of the response by the humanitarian community. The authors argue that the over-emphasis on food aid delivery occurred at the expense of other public health interventions, particularly preventative and curative health services. Health service needs were not sufficiently addressed despite the early recognition that ill-health related to HIV/AIDS was a major vulnerability factor. This neglect occurred because analytical frameworks were too narrowly focused on food security, and large-scale support to health service delivery was seen as a long-term developmental issue that could not easily be dealt with by short-term humanitarian action. Furthermore, there were insufficient countrywide data on acute malnutrition, mortality rates and performance of the public health system to make better-balanced evidence-based decisions. In this crisis, humanitarian organisations providing health services could not assume their traditional roles of short-term assistance in a limited geographical area until the governing authorities resume their responsibilities. However, relegating health service delivery as a long-term developmental issue is not acceptable. Improved multisectoral analytical frameworks that include a multidisciplinary team are needed to ensure all aspects of public health are dealt with in similar future emergencies. Humanitarian organisations must advocate for improved delivery and access to health services in this region. They can target limited geographical areas with high mortality and acute malnutrition rates to deliver their services. Finally, to

  16. Present and past microbial life in continental salt pan sediments in Southern Africa

    NASA Astrophysics Data System (ADS)

    Genderjahn, Steffi; Mangelsdorf, Kai; Alawi, Mashal; Kallmeyer, Jens; Wagner, Dirk

    2015-04-01

    The southwestern African region is characterized by strong climate variability. To get a better understanding on the climate evolution and environmental condition in Namibia and South Africa, terrestrial climate archives are investigated. Since there are almost no lakes, continental salt pans represent the only terrestrial geoarchives with the potential to preserve climate signals during sediment deposition. Climate has a strong impact on the salt pan ecosystem, causing adaptation of salt pan microorganisms to varying temperature, precipitation and salinity conditions. To reconstruct climate variability during the Holocene, the composition, diversity and abundance of indigenous microbial communities with depth and related to different soil parameters are investigated. We are using a combined approach of microbiological and lipid biomarker analyses to demonstrate the response of the microbial communities due to environmental changes. For microbiological analyses outcrops were conducted or short cores (0-100 cm) were drilled at four different salt pans in Aminuis, Koes and Witpan region having rather different geochemical properties. The current work focused on changes within the microbial communities due to the impact of long-term climate variation and the associated environmental changes and is part of the project 'Signals of climate and landscape change preserved in southern African GeoArchives' in the scope of the SPACES program, which is funded by the German Federal Ministry of Education and Research (BMBF). For a quantitative characterization of microbial communities molecular techniques such as polymerase chain reaction (PCR) and real-time quantitative PCR (qPCR) based on the 16S rRNA genes are used. Moreover, 454 sequencing technique is utilized to describe the diversity and abundance of microorganisms in detail. Soil parameters are described by standard soil scientific methods. Furthermore, microbial lipid biomarker analyses were done to characterize living

  17. MtDNA control region variation affirms diversity and deep sub-structure in populations from southern Africa

    PubMed Central

    2013-01-01

    Background The current San and Khoe populations are remnant groups of a much larger and widely dispersed population of hunter-gatherers and pastoralists, who had exclusive occupation of southern Africa before the influx of Bantu-speakers from 2 ka (ka = kilo annum [thousand years] old/ago) and sea-borne immigrants within the last 350 years. Here we use mitochondrial DNA (mtDNA) to examine the population structure of various San and Khoe groups, including seven different Khoe-San groups (Ju/’hoansi, !Xun, /Gui+//Gana, Khwe, ≠Khomani, Nama and Karretjie People), three different Coloured groups and seven other comparative groups. MtDNA hyper variable segments I and II (HVS I and HVS II) together with selected mtDNA coding region SNPs were used to assign 538 individuals to 18 haplogroups encompassing 245 unique haplotypes. Data were further analyzed to assess haplogroup histories and the genetic affinities of the various San, Khoe and Coloured populations. Where possible, we tentatively contextualize the genetic trends through time against key trends known from the archaeological record. Results The most striking observation from this study was the high frequencies of the oldest mtDNA haplogroups (L0d and L0k) that can be traced back in time to ~100 ka, found at high frequencies in Khoe-San and sampled Coloured groups. Furthermore, the L0d/k sub-haplogroups were differentially distributed in the different Khoe-San and Coloured groups and had different signals of expansion, which suggested different associated demographic histories. When populations were compared to each other, San groups from the northern parts of southern Africa (Ju speaking: !Xun, Ju/’hoansi and Khoe-speaking: /Gui+//Gana) grouped together and southern groups (historically Tuu speaking: ≠Khomani and Karretjie People and some Coloured groups) grouped together. The Khoe group (Nama) clustered with the southern Khoe-San and Coloured groups. The Khwe mtDNA profile was very different from other

  18. Modelled rainfall skill assessment against a 1000-year time/space isotope dendro-climatology for southern Africa

    NASA Astrophysics Data System (ADS)

    Woodborne, Stephan; Hall, Grant; Zhang, Qiong

    2016-04-01

    Palaeoclimate reconstruction using isotopic analysis of tree growth increments has yielded a 1000-year record of rainfall variability in southern Africa. Isotope dendro-climatology reconstructions from baobab trees (Adansonia digitata) provide evidence for rainfall variability from the arid Namib Desert and the Limpopo River Valley. Isotopic analysis of a museum specimen of a yellowwood tree (Podocarps falcatus) yields another record from the southwestern part of the subcontinent. Combined with the limited classic denro-climatologies available in the region these records yield palaeo-rainfall variability in the summer and winter rainfall zones as well as the hyper-arid zone over the last 1000 years. Coherent shifts in all of the records indicate synoptic changes in the westerlies, the inter-tropical convergence zone, and the Congo air boundary. The most substantial rainfall shift takes place at about 1600 CE at the onset of the Little Ice Age. Another distinctive feature of the record is a widespread phenomenon that occurs shortly after 1810 CE that in southern Africa corresponds with a widespread social upheaval known as the Difequane or Mfekane. Large scale forcing of the system includes sea-surface temperatures in the Agulhas Current, the El Nino Southern Oscillation and the Southern Annular Mode. The Little Ice Age and Mfekane climate shifts result from different forcing mechanisms, and the rainfall response in the different regions at these times do not have a fixed phase relationship. This complexity provides a good scenario to test climate models. A first order (wetter versus drier) comparison between each of the tree records and a 1000-year palaeoclimate model simulation for the Little Ice Age and Mfekane transitions demonstrates a generally good correspondence.

  19. Can differences in heat flow between east and southern Africa be easily interpreted?: Implications for understanding regional variability in continental heat flow

    NASA Astrophysics Data System (ADS)

    Nyblade, Andrew A.; Pollack, Henry N.

    1993-03-01

    We address the extent to which regional variations in continental heat flow can be interpreted, making use of a heat flow data set from east and southern Africa. The first-order observation deriving from these heat flow measurements is a common pattern characterized in both regions by low heat flow in Archean cratons and higher heat flow in younger mobile belts. Two regional differences between east and southern Africa are superimposed on this common heat flow pattern: (1) heat flow in the Tanzania Craton is about 13 mW m -2 lower than in the Kalahari Craton, and (2) heat flow in the Mozambique Belt in east Africa is about 9 mW m -2 lower than in the southern African mobile belts, within about 250 km of the respective Archean cratons. The differences in heat flow between east and southern Africa suggest that the thermal structure of the lithosphere beneath these regions differs somewhat, and we attempt to resolve these differences in lithospheric thermal structure by examining four explanations that could account for the heat flow observations: (1) diminished heat flow in shallow boreholes in east Africa; (2) less crustal heat production in the regions of lower heat flow; (3) thicker lithosphere beneath the regions of lower heat flow; (4) cooler mantle beneath the areas of lower heat flow. We find it difficult to interpret uniquely the heat flow differences between east and southern Africa because available constraints on crustal heat production, crustal structure, lithospheric thickness and mantle temperatures are insufficient to discriminate among the possible explanations. Hence, extracting significant information about lithospheric thermal structure from regional heat flow variations requires more ancillary geochemical and geophysical information than Africa presently offers.

  20. Non-Hodgkin lymphoma in Southern Africa: review of 487 cases from The International Non-Hodgkin Lymphoma Classification Project.

    PubMed

    Perry, Anamarija M; Perner, Yvonne; Diebold, Jacques; Nathwani, Bharat N; MacLennan, Kenneth A; Müller-Hermelink, Hans K; Bast, Martin; Boilesen, Eugene; Armitage, James O; Weisenburger, Dennis D

    2016-03-01

    Comparative data on the distribution of non-Hodgkin lymphoma (NHL) subtypes in Southern Africa (SAF) is scarce. In this study, five expert haematopathologists classified 487 consecutive cases of NHL from SAF using the World Health Organization classification, and compared the results to North America (NA) and Western Europe (WEU). Southern Africa had a significantly lower proportion of low-grade (LG) B-NHL (34·3%) and a higher proportion of high-grade (HG) B-NHL (51·5%) compared to WEU (54·5% and 36·4%) and NA (56·1% and 34·3%). High-grade Burkitt-like lymphoma was significantly more common in SAF (8·2%) than in WEU (2·4%) and NA (2·5%), most likely due to human immunodeficiency virus infection. When SAF patients were divided by race, whites had a significantly higher frequency of LG B-NHL (60·4%) and a lower frequency of HG B-NHL (32·7%) compared to blacks (22·5% and 62·6%), whereas the other races were intermediate. Whites and other races had a significantly higher frequency of follicular lymphoma and a lower frequency of Burkitt-like lymphoma compared to blacks. The median ages of whites with LG B-NHL, HG B-NHL and T-NHL (64, 56 and 67 years) were significantly higher than those of blacks (55, 41 and 34 years). Epidemiological studies are needed to better understand these differences. PMID:26898194

  1. Towards a gender perspective in qualitative research on voluntary medical male circumcision in east and southern Africa.

    PubMed

    Martínez Pérez, Guillermo; Triviño Durán, Laura; Gasch, Angel; Desmond, Nicole

    2015-01-01

    The World Health Organization endorsed voluntary medical male circumcision (VMMC) in 2007 as an effective method to provide partial protection against heterosexual female-to-male transmission of HIV in regions with high rates of such transmission, and where uptake of VMMC is low. Qualitative research conducted in east and southern Africa has focused on assessing acceptability, barriers to uptake of VMMC and the likelihood of VMMC increasing men's adoption of risky sexual behaviours. Less researched, however, have been the perceptions of women and sexual minorities towards VMMC, even though they are more vulnerable to HIV/AIDS transmission than are heterosexual men. The purpose of this paper is to identify core areas in which a gendered perspective in qualitative research might improve the understanding and framing of VMMC in east and southern Africa. Issues explored in this analysis are risk compensation, the post-circumcision appearance of the penis, inclusion of men who have sex with men as study respondents and the antagonistic relation between VMMC and female genital cutting. If biomedical and social science researchers explore these issues in future qualitative inquiry utilising a gendered perspective, a more thorough understanding of VMMC can be achieved, which could ultimately inform policy and implementation. PMID:25727455

  2. Shear wave velocity structure of the lower crust in southern Africa: Evidence for compositional heterogeneity within Archaean and Proterozoic terrains

    NASA Astrophysics Data System (ADS)

    Kgaswane, Eldridge M.; Nyblade, Andrew A.; Juliã, Jordi; Dirks, Paul H. G. M.; Durrheim, Raymond J.; Pasyanos, Michael E.

    2009-12-01

    The nature of the lower crust across the southern African shield has been investigated by jointly inverting receiver functions and Rayleigh wave group velocities for 89 broadband seismic stations located in Botswana, South Africa and Zimbabwe. For large parts of both Archaean and Proterozoic terrains, the velocity models obtained from the inversions show shear wave velocities ≥4.0 km/s below ˜20-30 km depth, indicating a predominantly mafic lower crust. However, for much of the Kimberley terrain and adjacent parts of the Kheis Province and Witwatersrand terrain in South Africa, as well as for the western part of the Tokwe terrain in Zimbabwe, shear wave velocities of ≤3.9 km/s are found below ˜20-30 km depth, indicating an intermediate-to-felsic lower crust. The areas of intermediate-to-felsic lower crust in South Africa coincide with regions where Ventersdorp rocks have been preserved, suggesting that the more evolved composition of the lower crust may have resulted from crustal reworking and extension during the Ventersdorp tectonomagmatic event at c. 2.7 Ga.

  3. Changing styles of crustal growth in Southern Africa: Constraints from geochemical and Sr-Nd isotope studies in Archaean to Pan African terrains

    NASA Technical Reports Server (NTRS)

    Mcdermott, F.; Hawkesworth, C. J.; Harris, N. B. W.

    1988-01-01

    Nd isotopic data was presented for southern Africa in support of episodic crustal growth. Over 50 percent of the continental crust there had formed before 2.5 Ga, and less than 10 percent was produced after about 1.0 Ga. The data imply a mean crustal age of about 2.4 Ga for southern Africa, and a higher rate of crustal growth than that derived from Australian shale data, particularly during the Proterozoic. Isotopic data from Damara metasediments imply that there is no need to invoke decoupling of the Rb-Sr and Sm-Nd systems in the continental crust.

  4. Southern African Treatment Resistance Network (SATuRN) RegaDB HIV drug resistance and clinical management database: supporting patient management, surveillance and research in southern Africa.

    PubMed

    Manasa, Justen; Lessells, Richard; Rossouw, Theresa; Naidu, Kevindra; Van Vuuren, Cloete; Goedhals, Dominique; van Zyl, Gert; Bester, Armand; Skingsley, Andrew; Stott, Katharine; Danaviah, Siva; Chetty, Terusha; Singh, Lavanya; Moodley, Pravi; Iwuji, Collins; McGrath, Nuala; Seebregts, Christopher J; de Oliveira, Tulio

    2014-01-01

    Substantial amounts of data have been generated from patient management and academic exercises designed to better understand the human immunodeficiency virus (HIV) epidemic and design interventions to control it. A number of specialized databases have been designed to manage huge data sets from HIV cohort, vaccine, host genomic and drug resistance studies. Besides databases from cohort studies, most of the online databases contain limited curated data and are thus sequence repositories. HIV drug resistance has been shown to have a great potential to derail the progress made thus far through antiretroviral therapy. Thus, a lot of resources have been invested in generating drug resistance data for patient management and surveillance purposes. Unfortunately, most of the data currently available relate to subtype B even though >60% of the epidemic is caused by HIV-1 subtype C. A consortium of clinicians, scientists, public health experts and policy markers working in southern Africa came together and formed a network, the Southern African Treatment and Resistance Network (SATuRN), with the aim of increasing curated HIV-1 subtype C and tuberculosis drug resistance data. This article describes the HIV-1 data curation process using the SATuRN Rega database. The data curation is a manual and time-consuming process done by clinical, laboratory and data curation specialists. Access to the highly curated data sets is through applications that are reviewed by the SATuRN executive committee. Examples of research outputs from the analysis of the curated data include trends in the level of transmitted drug resistance in South Africa, analysis of the levels of acquired resistance among patients failing therapy and factors associated with the absence of genotypic evidence of drug resistance among patients failing therapy. All these studies have been important for informing first- and second-line therapy. This database is a free password-protected open source database available on

  5. Nitrogen isotopic ecology in southern Africa: Implications for environmental and dietary tracing

    SciTech Connect

    Sealy, J.C.; Van Der Merwe, N.J.; Thorp, J.A.L.; Lanham, J.L. )

    1987-10-01

    In order to establish baseline nitrogen isotope data for certain African ecosystems, they have measured the {sup 15}N/{sup 14}N of some 300 marine and terrestrial organisms. The majority of these specimens come from the southwestern Cape, and were chosen to represent a cross-section of the foods important in prehistoric diets in the region. {delta}{sup 15}N analyses of 78 Holocene human skeletons from the same area are interpreted in the light of these results. Additional terrestrial animal samples were collected from the northern and eastern Cape and from Botswana and Malawi. They represent a wide range of climatic and environmental zones, from semi-desert to sub-tropical swamps. The patterning in the values for marine organisms is consistent with previously published data; that for terrestrial organisms, however, is more complex than recent studies have indicated. Their data confirm the proposal that animal {delta}{sup 15}N values vary with rainfall: high {delta}{sup 15}N values for herbivores occur in areas receiving less than 400 mm of rain per annum. They critically examine a recently proposed model explaining this phenomenon, and suggest some additional mechanisms which should be considered. In such arid areas, nitrogen isotope ratios cannot be used as marine/terrestrial indicators, but may provide some indication of the trophic level of the food consumed. Dietary studies on human populations can only be undertaken with a thorough appreciation of the isotopic ecology of the relevant foodweb.

  6. Phylogeny of anopheline (Diptera: Culicidae) species in southern Africa, based on nuclear and mitochondrial genes

    PubMed Central

    Norris, Douglas E.

    2016-01-01

    A phylogeny of anthropophilic and zoophilic anopheline mosquito species was constructed, using the nuclear internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome oxidase subunit I (COI) genes. The ITS2 alignment, typically difficult due to its noncoding nature and large size variations, was aided by using predicted secondary structure, making this phylogenetically useful gene more amenable to investigation. This phylogeny is unique in explicitly including zoophilic, non-vector anopheline species in order to illustrate their relationships to malaria vectors. Two new, cryptic species, Anopheles funestus-like and Anopheles rivulorum-like, were found to be present in Zambia for the first time. Sequences from the D3 region of the 28S rDNA suggest that the Zambian An. funestus-like may be a hybrid or geographical variant of An. funestus-like, previously reported in Malawi. This is the first report of An. rivulorum-like sympatric with An. rivulorum (Leeson), suggesting that these are separate species rather than geographic variants. PMID:26047180

  7. Epidemiology of lobomycosis-like disease in bottlenose dolphins Tursiops spp. from South America and southern Africa.

    PubMed

    Van Bressem, Marie-Françoise; Simões-Lopes, Paulo C; Félix, Fernando; Kiszka, Jeremy J; Daura-Jorge, Fabio G; Avila, Isabel C; Secchi, Eduardo R; Flach, Leonardo; Fruet, Pedro F; du Toit, Kate; Ott, Paulo H; Elwen, Simon; Di Giacomo, Amanda B; Wagner, Jeanne; Banks, Aaron; Van Waerebeek, Koen

    2015-11-17

    We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere. PMID:26575156

  8. Climate Change Adaptation and Climate Related Disaster Risk Reduction Strategies in Zimbabwe and Malawi

    NASA Astrophysics Data System (ADS)

    Mubaya, C. P.; Ngepah, N.; Seyama, W.

    2015-12-01

    Climate Change Adaptation (CCA) and Disaster Risk Reduction (DRR) have similar aims and mutual benefits, and there is a very strong rationale for adopting a more integrated approach to these issues rather than analysing each of them as distinct from the other. One of the gaps that have been noted in this context is the lack of evidence in systematic integration of CCA and DRR in Southern Africa. In this regard, this study builds on understanding CCA and DRR policies from the perspectives of vulnerable groups- women and smallholder farmers, and conducts institutional and policy analysis of CCA and DRR in southern Africa, with specific focus on Malawi and Zimbabwe. Both quantitative and qualitative methodologies were employed to collect data for this study in the two countries. The analysis is centred on the conceptualization of DRR in the context of recovery time and CCA on livelihood changes. Findings of the study show that drought is no longer viewed as a hazard as it is a perennial and chronic occurrence in selected climate hotspots, with heightened intensity in certain identified years. Households are able to quickly recover from slow onset hazards such as droughts and dry spells more than they are able to recover from sudden onset floods, implying more capacity towards CCA than DRR. Government programmes and policies are also focused more on CCA than on DRR efforts that appear not to be a priority. Findings point towards female vulnerability from perceptions and practice where males tend to dominate where they are set to benefit from external assistance. We need to strengthen government capacity in implementation of DRR programmes, which is currently limited and development initiatives must deliberately target building the resilience of women.

  9. The Late Pleistocene and Holocene palaeoenvironmental context of Wonderwerk Cave in the southern Kalahari, South Africa

    NASA Astrophysics Data System (ADS)

    Scott, Louis; Avery, Margaret; Bamford, Marion; Berna, Francesco; Brink, James; Brook, George; Chazan, Michael; Ecker, Michaela; Fernandez-Jalvo, Yolanda; Goldberg, Paul; Lee-Thorp, Julia; Rossouw, Lloyd; Thackeray, Francis; Horwitz, Liora

    2014-05-01

    Wonderwerk Cave, located in the arid southern Kalahari in South Africa, is an exceptional site, since it preserves a two million year long record of human occupation. While research on older levels in various excavation sections of the cave deposits is ongoing, we focus here on the younger levels that span the last 35,000 years. We present the results of past and recent work on zooarchaeology, macrobotany, palynology, phytoliths, stable isotopes, micromorphology and speleothem growth, which track marked diachronic environmental fluctuations. Except for a hiatus of ~33-23 ka, growth and isotope data for a speleothem near the cave entrance suggests moist conditions from ~35-33, and ~22-14 ka with brief, dry episodes at ~34, ~22 and ~15 ka. Temperatures were cool except for an increase ~16-14 ka after which cold conditions equivalent to the Younger Dryas event occurred. In Stratum 5 (>12.5 ka in Excavation 1), relatively low carbon isotope (δ13C) values, pollen in the speleothem, and pollen in dung deposits indicate that the vegetation included a large C3 component during this phase. While the climate experienced sharp fluctuations in moisture when stalagmite growth was interrupted, more severe drying occurred by ~12 ka as indicated by dung pollen. Pollen in Stratum 4d (undifferentiated by stratum sub-phases) suggest that warmer grassy conditions developed before 11 ka, which is supported by δ13C values in OES that suggest a greater C4plant component in Stratum 4dII associated with the Oakhurst-like archaeological industry. Undifferentiated Stratum 4d indicates moderate moisture availability (pollen) but sub-phase 4dII suggest drying (OES δ18O). C3-presence (OES δ13C) in the vegetation became stronger again in Stratum 4dI (Oakhurst) and Stratum 4cII (Wilton). This is supported by Asteraceae pollen especially ~8.5 ka. Except for a fluctuation in OES δ18O values in Stratum 4cII, δ18O and pollen and micromammal composition suggest progressive aridity until ~6 ka

  10. Identifying needs for streamflow forecasting in the Incomati basin, Southern Africa

    NASA Astrophysics Data System (ADS)

    Sunday, Robert; Werner, Micha; Masih, Ilyas; van der Zaag, Pieter

    2013-04-01

    Despite being widely recognised as an efficient tool in the operational management of water resources, rainfall and streamflow forecasts are currently not utilised in water management practice in the Incomati Basin in Southern Africa. Although, there have been initiatives for forecasting streamflow in the Sabie and Crocodile sub-basins, the outputs of these have found little use because of scepticism on the accuracy and reliability of the information, or the relevance of the information provided to the needs of the water managers. The process of improving these forecasts is underway, but as yet the actual needs of the forecasts are unclear and scope of the ongoing initiatives remains very limited. In this study questionnaires and focused group interviews were used to establish the need, potential use, benefit and required accuracy of rainfall and streamflow forecasts in the Incomati Basin. Thirty five interviews were conducted with professionals engaged in water sector and detailed discussions were held with water institutions, including the Inkomati Catchment Management Agency (ICMA), Komati Basin Water Authority (KOBWA), South African Weather Service (SAWS), water managers, dam operators, water experts, farmers and other water users in the Basin. Survey results show that about 97% of the respondents receive weather forecasts. In contrast to expectations, only 5% have access to the streamflow forecast. In the weather forecast, the most important variables were considered to be rainfall and temperature at daily and weekly time scales. Moreover, forecasts of global climatic indices such as El Niño or La Niña were neither received nor demanded. There was limited demand and/or awareness of flood and drought forecasts including the information on their linkages with global climatic indices. While the majority of respondents indicate the need and indeed use the weather forecast, the provision, communication and interpretation were in general found to be with too

  11. MODIS Observation of Aerosols over Southern Africa During SAFARI 2000: Data, Validation, and Estimation of Aerosol Radiative Forcing

    NASA Technical Reports Server (NTRS)

    Ichoku, Charles; Kaufman, Yoram; Remer, Lorraine; Chu, D. Allen; Mattoo, Shana; Tanre, Didier; Levy, Robert; Li, Rong-Rong; Kleidman, Richard; Lau, William K. M. (Technical Monitor)

    2001-01-01

    Aerosol properties, including optical thickness and size parameters, are retrieved operationally from the MODIS sensor onboard the Terra satellite launched on 18 December 1999. The predominant aerosol type over the Southern African region is smoke, which is generated from biomass burning on land and transported over the southern Atlantic Ocean. The SAFARI-2000 period experienced smoke aerosol emissions from the regular biomass burning activities as well as from the prescribed burns administered on the auspices of the experiment. The MODIS Aerosol Science Team (MAST) formulates and implements strategies for the retrieval of aerosol products from MODIS, as well as for validating and analyzing them in order to estimate aerosol effects in the radiative forcing of climate as accurately as possible. These activities are carried out not only from a global perspective, but also with a focus on specific regions identified as having interesting characteristics, such as the biomass burning phenomenon in southern Africa and the associated smoke aerosol, particulate, and trace gas emissions. Indeed, the SAFARI-2000 aerosol measurements from the ground and from aircraft, along with MODIS, provide excellent data sources for a more intensive validation and a closer study of the aerosol characteristics over Southern Africa. The SAFARI-2000 ground-based measurements of aerosol optical thickness (AOT) from both the automatic Aerosol Robotic Network (AERONET) and handheld Sun photometers have been used to validate MODIS retrievals, based on a sophisticated spatio-temporal technique. The average global monthly distribution of aerosol from MODIS has been combined with other data to calculate the southern African aerosol daily averaged (24 hr) radiative forcing over the ocean for September 2000. It is estimated that on the average, for cloud free conditions over an area of 9 million square kin, this predominantly smoke aerosol exerts a forcing of -30 W/square m C lose to the terrestrial

  12. Plume moths of Malawi (Lepidoptera: Pterophoridae).

    PubMed

    Kovtunovich, V; Ustjuzhanin, P; Murphy, R

    2014-01-01

    rubriacuta (Gielis, 2009) comb. nov.; Procapperia insomnis (Townsend, 1956) comb. nov.; Crassuncus ecstaticus (Meyrick, 1932) comb. nov.; Crassuncus colubratus (Meyrick, 1909) comb. nov. For Stenoptilia viettei Gibeaux, 1994, Sphenarches bifurcatus Gielis, 2009, Crassuncus ecstaticus (Meyrick, 1932) images of the male genitalia are presented for the first time, for Marasmarcha bengtssoni (Gielis, 2009), and Stenodacma cognata Gielis, 2009 female genitalia are illustrated for the first time. Species of wide pantropical or cosmopolitan distribution are not reported as new for the fauna of Malawi.  However, 65 species of Pterophoridae are reported for the fauna of Malawi for the first time.  One of them, Stenoptilia viettei Gibeaux, 1994, described from Madagascar, is reported for continental Africa for the first time.  PMID:25112354

  13. Crustal structure beneath southern Africa: insight into how tectonic events affect the Mohorovičić discontinuity

    NASA Astrophysics Data System (ADS)

    Delph, Jonathan R.; Porter, Ryan C.

    2015-01-01

    The long and complex history of southern Africa makes it a geological nexus for understanding how crust forms, evolves and survives plate tectonic processes over billions of years. The goal of this study is to characterize the crustal thickness, composition, and Moho impedance contrasts across the Kaapvaal and Zimbabwe Cratons and surrounding mobile belts, which range in age from Archean to Palaeozoic. We use data gathered from the 1997-1999 Southern Africa Seismic Experiment, the Africa Array (2006-2007) and the Global Seismographic Network (1993-2009) to generate P-wave receiver function Gaussian-weighted common conversion point stacks across the region in order to provide a continuous 3-D image of crustal variations throughout southern Africa. We observe thickened crust associated with mobile belts and the intrusion of the Bushveld Complex relative to the less-deformed cratons. The southern Kaapvaal and eastern Zimbabwe Cratons have a well-defined Moho with an average depth of ˜34 km and Vp/Vs of ˜1.73, indicative of felsic average crustal composition. We explain the felsic composition observed in the Kaapvaal Craton in the context of significant crustal modification related to the deposition of the Ventersdorp lavas. We find that the Bushveld Province, the site of the world's largest layered mafic intrusion, has a thick (>40 km) crust with a Vp/Vs > 1.8, indicative of a mafic average crustal composition. The magnitude of Moho conversions beneath the Bushveld Province is variable, with the lowest amplitude conversion appearing between the eastern and western limbs of the Bushveld Complex, indicative of mafic underplating beneath the region. In the Limpopo Belt and western Zimbabwe Craton, we observe low amplitude Moho conversions beneath the Okavango Dyke Swarm, and attribute this to the reworking of the crust by mafic underplating and intrusion during the Jurassic rifting of Gondwanaland. The Namaqua-Natal event thickened the crust and created a gradational

  14. Tertiary Education Curricula Internationalisation in Southern Africa: Its Impact on Global Employment Opportunities

    ERIC Educational Resources Information Center

    Gwakwa, Milton

    2016-01-01

    While education systems in Africa share common backgrounds historically (educationally, socially, politically, economically and culturally), they are deep variations in the approaches and contexts resulting in many questions than answers. The purpose of this study was to interrogate the current tertiary education curriculum, provide a rationale…

  15. Distance Education in Southern Africa Conference, 1987. Papers 6: Systems and Strategies in Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Eighteen papers from the University of South Africa's Conference on Distance Education are presented. They include: "Effective Second Language Reading in a Cross-Cultural Society" (Irma Zaslansky); "A BA Degree in Social Sciences at the Israel Open University" (Ruth Beyth-Marom); "Establishing a Theological Education by Extension Programme in…

  16. African Buffalo Movement and Zoonotic Disease Risk across Transfrontier Conservation Areas, Southern Africa

    PubMed Central

    Cornelis, Daniel; Foggin, Chris; Hofmeyr, Markus; de Garine-Wichatitsky, Michel

    2016-01-01

    We report on the long-distance movements of subadult female buffalo within a Transfrontier Conservation Area in Africa. Our observations confirm that bovine tuberculosis and other diseases can spread between buffalo populations across national parks, community land, and countries, thus posing a risk to animal and human health in surrounding wildlife areas. PMID:26812531

  17. Going to the Bush: Language, Power and the Conserved Environment in Southern Africa

    ERIC Educational Resources Information Center

    Cloete, Elsie L.

    2011-01-01

    English, in the words of Bill Bryson, "is one of the world's great growth industries". Like some kind of metalanguage with its own Europe-based meaning systems, it has constructed its own discourses in relation to Africa's conserved natural environment, nature documentaries, tourism and environmental education--at the expense of indigenous…

  18. African Buffalo Movement and Zoonotic Disease Risk across Transfrontier Conservation Areas, Southern Africa.

    PubMed

    Caron, Alexandre; Cornelis, Daniel; Foggin, Chris; Hofmeyr, Markus; de Garine-Wichatitsky, Michel

    2016-02-01

    We report on the long-distance movements of subadult female buffalo within a Transfrontier Conservation Area in Africa. Our observations confirm that bovine tuberculosis and other diseases can spread between buffalo populations across national parks, community land, and countries, thus posing a risk to animal and human health in surrounding wildlife areas. PMID:26812531

  19. Distance Education in Southern Africa Conference, 1987. Papers 7: Late Submissions.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Ten papers and four abstracts of papers from the University of South Africa's Conference on Distance Education are presented. They include: "Access to Higher Education and Training in the South Pacific: The Role of Telecommunications and Distance Education" (Som Naidu); "Distance Education in Japan" (Takashi Sakamoto); "The University for Distance…

  20. Distance Education in Southern Africa Conference, 1987. Papers 1: The Theory and Practice of Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Fifteen papers from the University of South Africa's Conference on Distance Education are presented on the theory and practice of distance education. Titles and authors include: "Evaluation at a Distance" (Margalit Ganor); "Can the Tables Be Turned? Likelihood That Distance Teaching at University Can Be More Effective Than Attendance Teaching"…

  1. The Efficacy of Prevention: Improving the Status of Children in Southern Africa.

    ERIC Educational Resources Information Center

    Norward, Josephine Norma

    1994-01-01

    Assesses a range of recent atrocities and apparently resultant problems experienced by children in areas of Namibia, Mozambique, and South Africa. Includes data from the literature and personal impressions from visits and extended periods of stay. Recommends expansion of birth control programs and awareness. (RAH)

  2. Distance Education in Southern Africa Conference, 1987. Papers 5: Administration and Student Support in Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Seventeen papers from the University of South Africa's Conference on Distance Education are presented. They include: "Establishing a Formal Student Support System--Time Is of the Essence" (Karen Hinrichs); "A Student Services Unit in a Distance Education Institution" (Hendrik Gous); "Distance Education and the Community: New Partnerships and…

  3. Key Factors in the Rise of Mass Popular Education and Their Relevance for Education in Southern Africa in the Twenty-First Century.

    ERIC Educational Resources Information Center

    van Niekerk, E. J.

    This paper identifies the historical factors that played a key role in the rise of mass popular education and describes how these factors relate to education in Southern Africa in the 21st century. The broad overview of developments since the Renaissance begins with the Protestant Reformation, which established a theoretical basis for elementary…

  4. Lack of genetic and plumage differentiation in the red-billed quelea Quelea quelea across a migratory divide in southern Africa.

    PubMed

    Dallimer, M; Jones, P J; Pemberton, J M; Cheke, R A

    2003-02-01

    A migratory divide usually signals the presence of a geographical region over which other traits, such as morphology and genotypes, also undergo rapid change. A migratory divide has been hypothesized in central southern Africa for the abundant migratory weaver, the red-billed quelea Quelea quelea. The positioning of the divide in the region is based on the patterns of rainfall in the region that stimulate the annual migrations of queleas. Evidence indicates that premigratory queleas near the divide show two distinct preferred directions for migration. We used eight polymorphic microsatellite loci and a range of plumage characters to determine whether there was population structure among red-billed queleas in southern Africa, and specifically whether this structure coincided with the location of the migratory divide. There was no evidence of population genetic structure. An amova revealed no significant differences between samples taken either side of the migratory divide. Similarly, there was no geographical variation in plumage patterns across southern Africa. For both microsatellites and plumage characteristics, the variation that does exist occurs within each sampled site, with little differentiation between sites. We were therefore unable to find any evidence that either plumage or microsatellite genotypes varied in a similar way to migratory direction preference in red-billed queleas in southern Africa. This is perhaps because the migratory divide does not act to separate individuals into populations within which genetic and plumage differentiation can be maintained. PMID:12535086

  5. The YES Africa 2011 Symposium: A Key to Developing the Future Geoscience Workforce in Africa

    NASA Astrophysics Data System (ADS)

    Nkhonjera, E.

    2011-12-01

    Africa is facing serious challenges in geoscience education. This has been as a result of absence of or very young/small Earth Science Departments in some universities (e.g., Mauritius, Namibia, Botswana, Swaziland, Malawi): Limited capacity (staff and equipment needed for practicals) to cope with the growing number of students, compounded by brain drain of academic staffs and the fact that current tertiary programmes do not seem to produce graduates suitable for the industry are some of the contributing factors to the challenges, (UNESCO-AEON Report, 2009). As such Earth Science studies in Africa have been one of the career paths that has not been promoted or highly preferred by many students. In January 2011, the YES Network African chapter was launched through the YES Africa 2011 Symposium that took place at the University of Johannesburg South Africa in Conjunction with the 23rd Colloquium of Africa Geology from the 08-14th January 2011. The YES Africa 2011 Symposium was organized by five YES African National networks from Southern, Central, Eastern and Northern Africa to bring young geoscientists from all regions of Africa together to present their research about African geoscience topics. The symposium also included roundtable discussions about increasing the involvement of youth's participation in geoscience issues in Africa, about how to increase the number of youths in African geosciences education university programs, and about how to promote geoscience careers to university students in Africa c. Roundtable discussions revealed that many African colleges and universities do not provide adequate infrastructure and resources to support the students studying in the department. As such, most students graduate with poor preparation for geoscience careers, having gained a theoretical understanding of geology, but not the practical application of the discipline. The recommendations from the YES Africa 2011 Symposium also highlighted on the best ways of

  6. South-South medical tourism and the quest for health in Southern Africa.

    PubMed

    Crush, Jonathan; Chikanda, Abel

    2015-01-01

    Intra-regional South-South medical tourism is a vastly understudied subject despite its significance in many parts of the Global South. This paper takes issue with the conventional notion of South Africa purely as a high-end "surgeon and safari" destination for medical tourists from the Global North. It argues that South-South movement to South Africa for medical treatment is far more significant, numerically and financially, than North-South movement. The general lack of access to medical diagnosis and treatment in SADC countries has led to a growing temporary movement of people across borders to seek help at South African institutions in border towns and in the major cities. These movements are both formal (institutional) and informal (individual) in nature. In some cases, patients go to South Africa for procedures that are not offered in their own countries. In others, patients are referred by doctors and hospitals to South African facilities. But the majority of the movement is motivated by lack of access to basic healthcare at home. The high demand and large informal flow of patients from countries neighbouring South Africa has prompted the South African government to try and formalise arrangements for medical travel to its public hospitals and clinics through inter-country agreements in order to recover the cost of treating non-residents. The danger, for 'disenfranchised' medical tourists who fall outside these agreements, is that medical xenophobia in South Africa may lead to increasing exclusion and denial of treatment. Medical tourism in this region and South-South medical tourism in general are areas that require much additional research. PMID:24973022

  7. Prediction, assessment of the Rift Valley fever activity in East and Southern Africa 2006-2008 and possible vector control strategies.

    PubMed

    Anyamba, Assaf; Linthicum, Kenneth J; Small, Jennifer; Britch, Seth C; Pak, Edwin; de La Rocque, Stephane; Formenty, Pierre; Hightower, Allen W; Breiman, Robert F; Chretien, Jean-Paul; Tucker, Compton J; Schnabel, David; Sang, Rosemary; Haagsma, Karl; Latham, Mark; Lewandowski, Henry B; Magdi, Salih Osman; Mohamed, Mohamed Ally; Nguku, Patrick M; Reynes, Jean-Marc; Swanepoel, Robert

    2010-08-01

    Historical outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns of the El Niño/Southern Oscillation (ENSO) phenomenon, which results in elevated and widespread rainfall over the RVF endemic areas of Africa. Using satellite measurements of global and regional elevated sea surface temperatures, elevated rainfall, and satellite derived-normalized difference vegetation index data, we predicted with lead times of 2-4 months areas where outbreaks of RVF in humans and animals were expected and occurred in the Horn of Africa, Sudan, and Southern Africa at different time periods from September 2006 to March 2008. Predictions were confirmed by entomological field investigations of virus activity and by reported cases of RVF in human and livestock populations. This represents the first series of prospective predictions of RVF outbreaks and provides a baseline for improved early warning, control, response planning, and mitigation into the future. PMID:20682905

  8. Prediction, Assessment of the Rift Valley Fever Activity in East and Southern Africa 2006–2008 and Possible Vector Control Strategies

    PubMed Central

    Anyamba, Assaf; Linthicum, Kenneth J.; Small, Jennifer; Britch, Seth C.; Pak, Edwin; de La Rocque, Stephane; Formenty, Pierre; Hightower, Allen W.; Breiman, Robert F.; Chretien, Jean-Paul; Tucker, Compton J.; Schnabel, David; Sang, Rosemary; Haagsma, Karl; Latham, Mark; Lewandowski, Henry B.; Magdi, Salih Osman; Mohamed, Mohamed Ally; Nguku, Patrick M.; Reynes, Jean-Marc; Swanepoel, Robert

    2010-01-01

    Historical outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns of the El Niño/Southern Oscillation (ENSO) phenomenon, which results in elevated and widespread rainfall over the RVF endemic areas of Africa. Using satellite measurements of global and regional elevated sea surface temperatures, elevated rainfall, and satellite derived-normalized difference vegetation index data, we predicted with lead times of 2–4 months areas where outbreaks of RVF in humans and animals were expected and occurred in the Horn of Africa, Sudan, and Southern Africa at different time periods from September 2006 to March 2008. Predictions were confirmed by entomological field investigations of virus activity and by reported cases of RVF in human and livestock populations. This represents the first series of prospective predictions of RVF outbreaks and provides a baseline for improved early warning, control, response planning, and mitigation into the future. PMID:20682905

  9. Prevalence and determinants of cigarette smoking among adolescents in Blantyre City, Malawi.

    PubMed

    Muula, A S

    2007-01-01

    Tobacco smoking is a major risk factor for non-communicable diseases such as ischaemic heart disease, stroke, chronic obstructive airways disease and several cancers. There is little data about the prevalence and determinants of smoking among adolescents in southern Africa. This study aimed to determine the prevalence and determinants of cigarette smoking among adolescents in Blantyre City, Malawi. Cross-sectional data were obtained from school-going adolescents in Blantyre in 2001 using the Global Youth Tobacco Survey data collection instrument. Data were analysed to determine prevalence of current and ever cigarette smoking, and predictors of smoking. The prevalence of current smoking and ever smoking were 3.0% and 15.6%, respectively. Predictors of current tobacco smoking included male gender, having friends or parents who smoked, having been exposed to advertisements about tobacco brands on television and having seen a lot of advertisements in newspapers and magazines. School programmes that included being taught about smoking in class and a class discussion on the dangers of tobacco were not associated with reduced current smoking. Intervention programmes aiming to curb tobacco smoking among adolescents should focus on dealing also with parental smoking, peer influence and pay special attention toward male gender. School-based programmes to prevent smoking should be evaluated as some may have little impact in influencing current smoking status. PMID:17547101

  10. Voluntary Medical Male Circumcision: A Qualitative Study Exploring the Challenges of Costing Demand Creation in Eastern and Southern Africa

    PubMed Central

    Bertrand, Jane T.; Njeuhmeli, Emmanuel; Forsythe, Steven; Mattison, Sarah K.; Mahler, Hally; Hankins, Catherine A.

    2011-01-01

    Background This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation? Methods and Findings We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to “trigger the decision” among eligible men. Conclusions Based on this study's findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the

  11. An Approach for Including Uncertainty in Integrated Water Resources Assessments within Large River Basins of Southern Africa.

    NASA Astrophysics Data System (ADS)

    Hughes, D.

    2015-12-01

    There are many large basins in southern Africa that are mostly ungauged but may have some streamflow observations either on the main river or on tributaries. Many of the streamflow records are, however, of poor quality or impacted by largely unquantified and non-stationary development impacts. All water resources assessments are therefore uncertain and model setups are difficult to validate in traditional ways. The paper presents a method for practical uncertainty assessment using a semi-distributed (sub-basin) model. The method uses a 2-stage approach where the first stage involves obtaining 'behavioural' parameter sets to represent the incremental natural streamflow for each sub-basin. The criteria for 'behavioural' are based on a series of constraints on model output that can be developed from the available gauged data or from regional assessments of natural hydrological functioning. The second stage simulates the whole basin based on sampling the 'behavioural' incremental flow parameter sets, as well as samples of additional individual parameter values representing downstream routing parts of the model and development impacts. One of the perceived advantage of the method is that all the ensembles at the total basin outlet are made up of behavioural inputs for all sub-basins. The method is also flexible in terms of the uncertainty range of the constraints, which might be expected to be narrow (low uncertainty) in well gauged sub-basins, or areas where our understanding of flow regime characteristics is good, but much wider (higher uncertainty) in other parts of the basin. The paper briefly explains the approach and discusses some of the issues associated with its application using examples from southern Africa.

  12. Climate and CO2 effects on the vegetation of southern tropical Africa over the last 37,000 years

    NASA Astrophysics Data System (ADS)

    Krebs-Kanzow, Uta; Khon, Vyacheslav C.; Wang, Yiming v.; Kaplan, Jed O.; Schneider, Birgit; Schneider, Ralph R.

    2014-05-01

    The savannah vegetation of southern tropical Africa is characterized by co-dominance of C4 grasslands and C3 woodlands. Long-term variations in the tropical savannah vegetation in arid and semi-arid climates are commonly considered to be primarily sensitive to precipitation and atmospheric CO2 concentrations. In our study we propose that also temperature changes should be considered when assessing the effect of a changing climate on tropical Savannahs. We combine BIOME4 vegetation simulations with climate simulations and climate reconstructions to understand vegetation changes in southern tropical Africa of the last 37,000 years. Precipitaion and vegetation reconstructions stem from the same marine sediment core near the Zambezi River mouth, temperatures were reconstructed from lake sediments within the Zambezi catchment. Our simulations demonstrate that temperature changes can reconcile a seemingly inconsistent evolution in precipitation, atmospheric CO2 and vegetation change. We focus on two periods for which the vegetation reconstructions cannot be explained alone by precipitation changes and changes of atmosphere CO2: (i) For the Holocene, we force BIOME4 simulations with reconstructed atmospheric CO2 concentrations, and spatial and seasonal climate patterns from the early- and mid-Holocene (9 and 6 ka BP) simulations with a global climate model. (ii) For the glacial period, we analyze idealized experiments based upon reconstructed temperature, precipitation and CO2 at 31, 28 and 21 ka BP. Our study shows that both Holocene and glacial simulations of vegetation cover exhibit good agreement with reconstructed C4:C3 ratios when temperature changes are taken into account. Adapting and refining this approach might permit to constrain continental temperature reconstructions or to evaluate the sensitivity of vegetation models to long term climate variations.

  13. Monitoring vegetation dynamics with medium resolution MODIS-EVI time series at sub-regional scale in southern Africa

    NASA Astrophysics Data System (ADS)

    Dubovyk, Olena; Landmann, Tobias; Erasmus, Barend F. N.; Tewes, Andreas; Schellberg, Jürgen

    2015-06-01

    Currently there is a lack of knowledge on spatio-temporal patterns of land surface dynamics at medium spatial scale in southern Africa, even though this information is essential for better understanding of ecosystem response to climatic variability and human-induced land transformations. In this study, we analysed vegetation dynamics across a large area in southern Africa using the 14-years (2000-2013) of medium spatial resolution (250 m) MODIS-EVI time-series data. Specifically, we investigated temporal changes in the time series of key phenometrics including overall greenness, peak and timing of annual greenness over the monitoring period and study region. In order to specifically capture spatial and per pixel vegetation changes over time, we calculated trends in these phenometrics using a robust trend analysis method. The results showed that interannual vegetation dynamics followed precipitation patterns with clearly differentiated seasonality. The earliest peak greenness during 2000-2013 occurred at the end of January in the year 2000 and the latest peak greenness was observed at the mid of March in 2012. Specifically spatial patterns of long-term vegetation trends allowed mapping areas of (i) decrease or increase in overall greenness, (ii) decrease or increase of peak greenness, and (iii) shifts in timing of occurrence of peak greenness over the 14-year monitoring period. The observed vegetation decline in the study area was mainly attributed to human-induced factors. The obtained information is useful to guide selection of field sites for detailed vegetation studies and land rehabilitation interventions and serve as an input for a range of land surface models.

  14. The anthropogenic contribution to atmospheric black carbon concentrations in southern Africa: a WRF-Chem modeling study

    NASA Astrophysics Data System (ADS)

    Kuik, F.; Lauer, A.; Beukes, J. P.; Van Zyl, P. G.; Josipovic, M.; Vakkari, V.; Laakso, L.; Feig, G. T.

    2015-08-01

    South Africa has one of the largest industrialized economies in Africa. Emissions of air pollutants are particularly high in the Johannesburg-Pretoria metropolitan area, the Mpumalanga Highveld and the Vaal Triangle, resulting in local air pollution. This study presents and evaluates a setup for conducting modeling experiments over southern Africa with the Weather Research and Forecasting model including chemistry and aerosols (WRF-Chem), and analyzes the contribution of anthropogenic emissions to the total black carbon (BC) concentrations from September to December 2010. The modeled BC concentrations are compared with measurements obtained at the Welgegund station situated ca. 100 km southwest of Johannesburg. An evaluation of WRF-Chem with observational data from ground-based measurement stations, radiosondes, and satellites shows that the meteorology is modeled mostly reasonably well, but precipitation amounts are widely overestimated and the onset of the wet season is modeled approximately 1 month too early in 2010. Modeled daily mean BC concentrations show a temporal correlation of 0.66 with measurements, but the total BC concentration is underestimated in the model by up to 50 %. Sensitivity studies with anthropogenic emissions of BC and co-emitted species turned off show that anthropogenic sources can contribute up to 100 % to BC concentrations in the industrialized and urban areas, and anthropogenic BC and co-emitted species together can contribute up to 60 % to PM1 levels. Particularly the co-emitted species contribute significantly to the aerosol optical depth (AOD). Furthermore, in areas of large-scale biomass-burning atmospheric heating rates are increased through absorption by BC up to an altitude of about 600hPa.

  15. Social support as a protective factor for children impacted by HIV/AIDS across varying living environments in southern Africa.

    PubMed

    Barenbaum, Edna; Smith, Tamarah

    2016-03-01

    The literature on the psychological well-being of children impacted by HIV/AIDS in Africa highlights increased vulnerability due to loss of parents and environmental stressors (e.g., hunger). Research shows that the lack of attachment and social support due to loss limits the grieving process in children. Access to trusting adults and social support through caregivers can be an important protective factor to allow for coping and better emotional adjustment in the future. This study examined social support systems across varying living environments to determine if social support promoted higher levels of well-being in children orphaned and made vulnerable by HIV/AIDS. The participants included 100 children from a small targeted population in southern Africa who receive varying levels of support from a private not-for-profit organization. Children's well-being was assessed through the Psycho-Social Adjustment Scale-Adolescents developed specifically for vulnerable child populations in Africa. Children were individually interviewed either on their homestead, school or hostel. Data demonstrated that children who do not share their feelings had significantly lower measures of positive well-being (M = 2.61 (0.87) vs. M = 3.10 (0.57), d = 0.60). Children with trusted adults were significantly more likely to share their feelings and had lower incidence of hunger (49.1% vs. 62.5%), suicide ideation (15.1% vs. 62.5%) and witnessing violence (69.8% vs. 87.5%). Sharing feelings with caregivers was more pronounced among children who had greater access to trusted adults and correlated with stronger attachment scores (r = .30, p < .01). An important component to decrease levels of anxiety and depression in this vulnerable population is providing access to trusted individuals. Social support interventions are discussed. PMID:27392004

  16. Social support as a protective factor for children impacted by HIV/AIDS across varying living environments in southern Africa

    PubMed Central

    Barenbaum, Edna; Smith, Tamarah

    2016-01-01

    ABSTRACT The literature on the psychological well-being of children impacted by HIV/AIDS in Africa highlights increased vulnerability due to loss of parents and environmental stressors (e.g., hunger). Research shows that the lack of attachment and social support due to loss limits the grieving process in children. Access to trusting adults and social support through caregivers can be an important protective factor to allow for coping and better emotional adjustment in the future. This study examined social support systems across varying living environments to determine if social support promoted higher levels of well-being in children orphaned and made vulnerable by HIV/AIDS. The participants included 100 children from a small targeted population in southern Africa who receive varying levels of support from a private not-for-profit organization. Children’s well-being was assessed through the Psycho-Social Adjustment Scale-Adolescents developed specifically for vulnerable child populations in Africa. Children were individually interviewed either on their homestead, school or hostel. Data demonstrated that children who do not share their feelings had significantly lower measures of positive well-being (M = 2.61 (0.87) vs. M = 3.10 (0.57), d = 0.60). Children with trusted adults were significantly more likely to share their feelings and had lower incidence of hunger (49.1% vs. 62.5%), suicide ideation (15.1% vs. 62.5%) and witnessing violence (69.8% vs. 87.5%). Sharing feelings with caregivers was more pronounced among children who had greater access to trusted adults and correlated with stronger attachment scores (r = .30, p < .01). An important component to decrease levels of anxiety and depression in this vulnerable population is providing access to trusted individuals. Social support interventions are discussed. PMID:27392004

  17. Geochemistry and petrogenesis of mafic sills in the 1.1 Ga Umkondo large igneous province, southern Africa

    NASA Astrophysics Data System (ADS)

    Bullen, D. S.; Hall, R. P.; Hanson, R. E.

    2012-06-01

    The detailed petrogenesis of mafic sills occurring throughout southern Africa provides strong support for the development of an Umkondo large igneous province on the eastern margin of the Kalahari craton at 1.1 Ga. The sills are most extensively developed in the Waterberg and Middelburg basins in northern South Africa and south-eastern Botswana. They are typical fractionated continental tholeiites with subophitic to ophitic dolerites, gabbros and gabbro-norites, and largely basaltic andesite in composition. The vast majority of the sample set defines one major geochemical subgroup, here referred to as the Mesoproterozoic Post-Waterberg sills A (MPWA sills), which is characteristically LREE enriched with relatively unfractionated HREEs, and with normalised incompatible element profiles similar to modern island arc andesites. A small number from the sample set define a minor subgroup (MPWB sills), which has so far only been recognised in the Middelburg basin, South Africa and which is characterized by fractionated HREEs. Both the major and trace element geochemical signatures of the MPWA sills are indistinguishable from the type Umkondo sills and less common lavas documented from Eastern Zimbabwe and mafic sills on the Grunehogna craton in present day Eastern Antarctica. This provides strong supporting evidence for an Umkondo large igneous province developed on the Kalahari craton at 1.1 Ga. Despite crustal-type Sr-Nd isotopic signatures in the MPWA sills, bulk contamination by the continental crust is ruled out in favour of derivation from a primitive mantle-like asthenospheric source with a contribution from the subcontinental lithospheric mantle modified by a previous subduction event. The smaller MPWB magma type could represent a smaller degree melt at greater depth from a modified MORB-like source, although the relationship between the two subgroups remains unclear.

  18. Predicting The Rainy Season Over Southern West Africa From Global Predictors and Climate Model Output: A Mos Approach

    NASA Astrophysics Data System (ADS)

    Paeth, H.; Born, K.; Hense, A.

    As 75 % of annual precipitation over the Sahel and Guinea Coast region are confined to the rainy season between June and September, prediction of this season is largely rel- evant in terms of fresh water availability for vegetation and human activity. Therefore, we present various global near-surface predictors of summertime rainfall for different regions of West Africa. The most important predictability arises from more regional information such as the SST in the tropical and subtropical Atlantic or the large-scale surface pressure field over the West African subcontinent. However, there are some teleconnections to the tropical Pacific, involving ENSO and the Walker circulation. The extratropical circulation modes such as the NAO play a minor role over the north- western part of West Africa. Based on the whole 20th century validation period the impact of increasing GHG is barely apparent. The same goes for all India rainfall and the QBO. Using multiple regression and cross validation a forecast model for the rainy season is developped by which we gain insight into the optimal number of relevant predictors. Thus, predictors which result from statistical correlation rather than physical rela- tionship are discarded. The remaining predictors, partly derived from the EOF space, account for around 55 % of the simulated interannual variability. In terms of the ob- servations, the forecast model is composed of the global predictors mentioned above and the simulated seasonal rainfall from different global climate models. Then, the method reveals a forecast potential of slightly more than 50 % for the observed inter- annual variations in summertime rainfall over southern West Africa. Given the strong autocorrelation of tropical SST, our approach could be used for operational seasonal forecasting with reasonable computing time.

  19. Growth of early archaean crust in the ancient Gneiss complex of Swaziland and adjacent Barberton Greenstone Belt, Southern Africa

    NASA Technical Reports Server (NTRS)

    Kroener, A.; Compston, W.; Tegtmeyer, A.; Milisenda, C.; Liew, T. C.

    1988-01-01

    The relationship between early Archean greenstones and high grade gneisses in the Ancient Gneiss Complex of Swaziland and the neighboring Barberton greenstone belt in Southern Africa is discussed. New high precision zircon analyses reveal a complex history in individual zircons from tonalitic orthogneisses, with ages as old as 3644 + 4 Ma. This suggests the presence of continental crust prior to the formation of the supracrustal rocks of the Barberton greenstone belt, which have been previously considered the earliest rocks in the area. The author suggested that these data are incompatible with the intraoceanic settings that have been widely accepted for this terrane, and favors either a marginal basin or rift environment. By using the detailed age information obtained from zircons in combination with Ar-40 and Ar-39 and paleomagnetic measurements, the author estimated that plate velocities for this part of Africa craton were about 10 to 70 mm/yr, during the period 3.4 to 2.5 Ga. This is not incompatible with the idea that Archean plate velocities may have been similiar to those of today.

  20. Moisture source and diet affect development and reproduction of Orius thripoborus and Orius naivashae, two predatory anthocorids from Southern Africa.

    PubMed

    Bonte, Jochem; Vangansbeke, Dominiek; Maes, Sara; Bonte, Maarten; Conlong, Des; De Clercq, Patrick

    2012-01-01

    The effect of moisture source and diet on the development and reproduction of the pirate bugs, Orius thripoborus (Hesse) and Orius naivashae (Poppius) (Hemiptera: Anthocoridae) was examined in the laboratory. Both species had been collected in and around sugarcane fields in South Africa. Supplementing eggs of the flour moth Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) with a green bean pod as a moisture source yielded better nymphal survival and faster development, as compared with free water encapsulated in Parafilm, suggesting that the predators may extract extra nutrients from the bean pod. The impact of two factitious foods and moist honey bee pollen on developmental and reproductive parameters of both predators was also investigated. The overall performance of both Orius species on E. kuehniella eggs and cysts of brine shrimp, Artemia franciscana Kellogg (Crustacea: Artemiidae) was better than on pollen. Nonetheless, a pollen diet alone allowed 66 and 78% of the nymphs of O. thripoborus and O. naivashae, respectively, to reach adulthood. Overall, developmental and reproductive performance of O. thripoborus on the tested diets was superior to that of O. naivashae. The implications of these findings for the mass production of these predators and their potential role in biological control programs in southern Africa are discussed. PMID:22935002

  1. Moisture Source and Diet affect Development and Reproduction of Orius thripoborus and Orius naivashae, two Predatory Anthocorids from Southern Africa

    PubMed Central

    Bonte, Jochem; Vangansbeke, Dominiek; Maes, Sara; Bonte, Maarten; Conlong, Des; Clercq, Patrick De

    2012-01-01

    The effect of moisture source and diet on the development and reproduction of the pirate bugs, Orius thripoborus (Hesse) and Orius naivashae (Poppius) (Hemiptera: Anthocoridae) was examined in the laboratory. Both species had been collected in and around sugarcane fields in South Africa. Supplementing eggs of the flour moth Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) with a green bean pod as a moisture source yielded better nymphal survival and faster development, as compared with free water encapsulated in Parafilm, suggesting that the predators may extract extra nutrients from the bean pod. The impact of two factitious foods and moist honey bee pollen on developmental and reproductive parameters of both predators was also investigated. The overall performance of both Orius species on E. kuehniella eggs and cysts of brine shrimp, Artemia franciscana Kellogg (Crustacea: Artemiidae) was better than on pollen. Nonetheless, a pollen diet alone allowed 66 and 78% of the nymphs of O. thripoborus and O. naivashae, respectively, to reach adulthood. Overall, developmental and reproductive performance of O. thripoborus on the tested diets was superior to that of O. naivashae. The implications of these findings for the mass production of these predators and their potential role in biological control programs in southern Africa are discussed. PMID:22935002

  2. A review of 40 years of hydrological science and practice in southern Africa using the Pitman rainfall-runoff model

    NASA Astrophysics Data System (ADS)

    Hughes, D. A.

    2013-09-01

    The 40th anniversary of the initial development of the Pitman rainfall-runoff (developed in South Africa and widely applied throughout southern Africa) approximately coincides with the end of the IAHS PUB programme and the start of a new decade focussing on hydrological change (Panta Rhei) and society. The paper reviews the developments and applications of the Pitman model in the context of the appropriate outcomes of PUB and the proposed future directions of Panta Rhei. The focus of development of the Pitman model has been dominated by practical applications, while PUB was largely dominated by science issues. While some of the PUB principles have been applied with the Pitman model, there are others that are deemed inappropriate for practical modelling and others that would almost certainly benefit the Pitman model applications in the future. The paper includes discussions of the model structure, input data, parameters and output evaluations - all in the context of uncertainty. The capabilities of the model to address societal development impacts are also discussed and a brief example of an uncertainty approach to applying the model is provided. The conclusions are that some developments of the Pitman model anticipated more recent international developments, while others have not been ignored even if further efforts are required to effectively implement them. Perhaps the largest gap in applying uncertainty principles in practice is how to use them in water resources decision making.

  3. A new analysis of variability and predictability of seasonal rainfall of central southern Africa for 1950-94

    NASA Astrophysics Data System (ADS)

    Mwale, Davison; Yew Gan, Thian; Shen, Samuel S. P.

    2004-10-01

    Using wavelet analysis and wavelet-based empirical orthogonal function analysis on scale-averaged-wavelet power and individual scale power, we identified the non-stationary sea-surface temperature (SST) fields of the South Atlantic and Indian Oceans that are associated with coherent regions of rainfall variability in central southern Africa (CSA). The dominant mode of CSA rainfall is out of phase between the coastal areas and the centre of CSA and has been decreasing consistently since 1970. The frequencies associated with this mode are between 2-2.4 and 5.6-8 years. The Benguela ocean current SSTs form the dominant spatial pattern of the South Atlantic Ocean, and the Brazil and Guinea ocean current SSTs form the second leading mode. The Benguela spatial patterns were found to migrate seasonally between Africa's west coast and South America's east coast. The northern Indian Ocean SST forms the leading mode of variability, followed by the south Indian Ocean SST. Using predictor fields identified from both oceans, we achieved encouraging results of predicted CSA rainfall using a non-linear statistical teleconnection artificial neural network-genetic algorithm model. At 3 month lead time, correlations of between 0.8 and 0.9, root-mean-square errors of between 0.4 and 0.9 and Hansen Kuipers skill scores of between 0.4 and 0.8 were obtained between observed and predicted CSA rainfall.

  4. Growth of early archaean crust in the ancient Gneiss complex of Swaziland and adjacent Barberton Greenstone Belt, Southern Africa

    NASA Astrophysics Data System (ADS)

    Kroener, A.; Compston, W.; Tegtmeyer, A.; Milisenda, C.; Liew, T. C.

    The relationship between early Archean greenstones and high grade gneisses in the Ancient Gneiss Complex of Swaziland and the neighboring Barberton greenstone belt in Southern Africa is discussed. New high precision zircon analyses reveal a complex history in individual zircons from tonalitic orthogneisses, with ages as old as 3644 + 4 Ma. This suggests the presence of continental crust prior to the formation of the supracrustal rocks of the Barberton greenstone belt, which have been previously considered the earliest rocks in the area. The author suggested that these data are incompatible with the intraoceanic settings that have been widely accepted for this terrane, and favors either a marginal basin or rift environment. By using the detailed age information obtained from zircons in combination with Ar-40 and Ar-39 and paleomagnetic measurements, the author estimated that plate velocities for this part of Africa craton were about 10 to 70 mm/yr, during the period 3.4 to 2.5 Ga. This is not incompatible with the idea that Archean plate velocities may have been similiar to those of today.

  5. Africa's present and future needs in toxicology education: Southern African perspective

    SciTech Connect

    Gulumian, Mary . E-mail: mary.gulumian@nioh.nhls.co.za; Ginsburg, Carren; Stewart, Michael J.

    2005-09-01

    Degrees and diplomas as well as certificates that are granted by universities and technikons in South Africa in scientific disciplines, such as forensic medicine, pharmacology, marine and veterinary sciences, environmental health, and occupational hygiene, include toxicology as one of the subjects in their overall syllabus. However, aspects of toxicology included in each of these courses are biased towards that particular subdiscipline and basic level of toxicology may be taught. Educational needs in toxicology in South Africa can be summarized as follows: (a) recognition of toxicology as a discipline in its own right at these tertiary education institutions and (b) creation of opportunities to study and obtain higher degrees in one or more of the many subdisciplines of toxicology. The results from a survey conducted on the toxicology syllabi offered at these tertiary education institutions are used to substantiate these needs.

  6. Descriptions of members of the Simulium damnosum complex (Diptera: Simuliidae) from southern Africa, Ethiopia and Tanzania.

    PubMed

    Krüger, A; Car, M; Maegga, B T A

    2005-04-01

    This paper presents cytotaxonomic details of five populations of the Simulium damnosum complex from South Africa, Swaziland and Ethiopia. The 'Nkusi SW' and 'Pienaars' forms are newly designated members of the complex from South Africa, but the taxonomic rank of an isolate indistinguishable chromosomally from the 'Nkusi' cytoform remains unclear. From Ethiopia two cytoforms were identified, one of which shares two diagnostic chromosome inversions with the cytoform 'Kisiwani' from Tanzania. The second form belongs to S. kaffaense, and is the suspected local vector of Onchocerca volvulus. In addition, a re-analysis of the cytoform 'Kibwezi' from north-eastern Tanzania provided further insights into its population subdivision, and its genetic and morphological characteristics. Cytotaxonomic similarities between 'Kibwezi', S. mengense and S. pandanophilum, along with their biogeography, indicate a relict status of each of these taxa. PMID:15829137

  7. Is normative integrated water resources management implementable? Charting a practical course with lessons from Southern Africa

    NASA Astrophysics Data System (ADS)

    Merrey, D. J.

    At the seventh Waternet/WARFSA/GWP-SA Symposium, Lewis Jonker described the “perceived failure of implementing IWRM in South Africa.” This paper starts from Jonker’s observation - which can certainly be defended - and argues that attempts to implement full Integrated Water Resources Management (IWRM) are doomed to failure and disappointment. The paper therefore offers a more practical ‘expedient’ solution. The paper is based on research done in Tanzania (Ruaha Basin) and South Africa (Olifants Basin) that is further informed by a growing literature critical of the IWRM paradigm as currently understood and practiced. As a guide to actual policies and their implementation in developing countries, IWRM has led to mis-guided priorities and paralysis of development programmes. An alternative approach is one in which basin managers identify priority problem areas, and focus specifically on finding solutions to these problems within an integrated framework, rather than starting with a broad set of principles and trying to implement these. The paper proposes that a shift away from IWRM as a normative concept is now overdue, and argues for realism and action by focusing attention on and prioritizing the critical needs of poor people in Africa. People cannot wait forever .

  8. An estimate of the area burned in southern Africa during the 2000 dry season using SPOT-VEGETATION satellite data

    NASA Astrophysics Data System (ADS)

    Silva, JoãO. M. N.; Pereira, José M. C.; Cabral, Ana I.; Sá, Ana C. L.; Vasconcelos, Maria J. P.; Mota, Bernardo; GréGoire, Jean-Marie

    2003-07-01

    The area burned in southern Africa during the 2000 dry season was mapped on a monthly basis from May to November using SPOT-VEGETATION (VGT) satellite imagery at 1 km spatial resolution. Burned areas were identified with a classification tree that relied only on the near-infrared channel of VGT. The classification tree algorithm yielded very accurate results (Kappa = 0.93). However, when compared with burned area maps derived from 30 m resolution Landsat Enhanced Thematic Mapper (ETM+) imagery, the VGT 1 km burned area maps reveal variable accuracy, dependent on vegetation type and on the spatial pattern of the burned areas. Fire incidence was higher in the northern part of the study area, especially in Wetter Zambezian Miombo Woodland, Mosaic of Guineo-Congolian Lowland Forest and Secondary Grassland, Edaphic and Secondary Grassland on Kalahari Sand, Drier Zambezian Miombo Woodland, and Undifferentiated North-Zambezian Miombo Woodland. Fire incidence was lower in the eastern part of the study area and almost absent from the western and southern semiarid and desert regions. The most extensively burned countries were, in decreasing order, the Democratic Republic of Congo, Angola, Mozambique and Zambia. The total area burned was estimated at 959480 km2.

  9. Adult Literacy Policies and Performance in the SADCC Region (Southern Africa).

    ERIC Educational Resources Information Center

    Bhola, H. S.

    While the implementation of adult literacy promotion can best be handled at the national level, some important things can be done at the Southern African Development Co-ordination Conference (SADCC) level. A persuasive argument can be made on behalf of adult literacy in the SADCC development strategy. The people need to be educated in the…

  10. Empowering biotechnology in southern Africa: establishment of a robust transformation platform for the production of transgenic industry-preferred cassava.

    PubMed

    Chetty, C C; Rossin, C B; Gruissem, W; Vanderschuren, H; Rey, M E C

    2013-01-25

    improvement in South Africa (SA), which can potentially be extended to other countries in southern Africa. The successful establishment of a robust cassava transformation and regeneration system in SA demonstrates the relevance of technology transfer to sub-Saharan Africa and highlights the importance of developing suitable and reliable techniques before their transfer to laboratories offering less optimal conditions. PMID:22683498

  11. The Score Reliability of Draw-a-Person Intellectual Ability Test (DAP: IQ) for Rural Malawi Students

    ERIC Educational Resources Information Center

    Khasu, Denis S.; Williams, Thomas O., Jr.

    2016-01-01

    In this brief article, the reliability of scores for the Draw-A-Person Intellectual Ability Test for Children, Adolescents, and Adults (DAP: IQ; Reynolds & Hickman, 2004) was examined through several analyses with a sample of 147 children from rural Malawi, Africa using a Chichewa translation of instructions. Cronbach alpha coefficients for…

  12. The Machinga, Malawi, meteorite - A recent L6 fall

    NASA Astrophysics Data System (ADS)

    Graham, A. L.; Crow, M. J.; Chatupa, J. C.; Mndala, A. T.

    1984-06-01

    The Machinga meteorite fell in the Southern Province of Malawi on January 22, 1981, at approximately 1000 hours local time. The fall site is about 7.5 km SW. of Machinga and has the coordinates 15 deg 12 min 44 sec S, 35 deg 14 min 32 sec E. A single crusted mass weighing 93.2 kg was recovered. The Machinga meteorite is an L6 chondrite with olivine Fa(24.5) and orthopyroxene Fs(21.1). The silicates have a granular texture and the stone has been shocked.

  13. IBFAN Africa training initiatives: code implementation and lactation management.

    PubMed

    Mbuli, A

    1994-01-01

    As part of an ongoing effort to halt the decline of breast feeding rates in Africa, 35 representatives of 12 different African countries met in Mangochi, Malawi, in February 1994. The Code of Marketing of Breastmilk Substitutes was scrutinized. National codes were drafted based on the "Model Law" of the IBFAN Code Documentation Centre (ICDC), Penang. Mechanisms of implementation, specific to each country, were developed. Strategies for the promotion, protection, and support of breast feeding, which is very important to child survival in Africa, were discussed. The training course was organized by ICDC, in conjunction with IBFAN Africa, and with the support of the United Nations Children's Fund (UNICEF) and the World Health Organization (WHO). Countries in eastern, central, and southern Africa were invited to send participants, who included professors, pediatricians, nutritionists, MCH personnel, nurses, and lawyers. IBFAN Africa has also been conducting lactation management workshops for a number of years in African countries. 26 health personnel (pediatricians, nutritionists, senior nursing personnel, and MCH workers), representing 7 countries in the southern African region, attended a training of trainers lactation management workshop in Swaziland in August, 1993 with the support of their UNICEF country offices. The workshop included lectures, working sessions, discussions, and slide and video presentations. Topics covered included national nutrition statuses, the importance of breast feeding, the anatomy and physiology of breast feeding, breast feeding problems, the International Code of Marketing, counseling skills, and training methods. The field trip to a training course covering primary health care that was run by the Traditional Healers Organization (THO) in Swaziland was of particular interest because of the strong traditional medicine sector in many African countries. IBFAN Africa encourages use of community workers (traditional healers, Rural Health

  14. Salt deformation history and postsalt structural trends, offshore southern Gabon, West Africa

    SciTech Connect

    Liro, L.M.; Coen, R.

    1996-12-31

    Salt deformation in offshore southern Gabon is represented by mobilization of an Aptian salt layer in reaction to Tertiary clastic progradation. Seismic mapping of salt bodies and associated faulting has resulted in increased understanding of the types and distribution of these salt bodies, their associated faulting patterns, and some aspects of their origin. Away from the Tertiary depocenter, the growth history of salt swells or pillows can be determined by examining onlapping and draping seismic reflectors. Significant Tertiary clastic progradation into the area mobilized the salt and resulted in a series of linear, deep salt walls and asymmetric, basinward-dipping salt rollers, commonly associated with significant up-to-basin faulting dominates the southern Gabon subbasin. The expansion history of associated sediments suggests that these faults expanded episodically throughout the Tertiary, continuing to present-day bathymetric fault scarps. The bias toward up-to-basin faults, to the apparent exclusion of down-to-basin expansion faults, remains enigmatic.

  15. Ectoparasite Burdens of the Damaraland Mole-Rat (Fukomys damarensis) from Southern Africa.

    PubMed

    Lutermann, Heike; Carpenter-Kling, Tegan; Ueckermann, Edward A; Gutjahr, Gundula; Bennett, Nigel C

    2015-12-01

    Damaraland mole-rats (Fukomys damarensis) of the family Bathyergidae are widely distributed subterranean rodents in sub-Saharan Africa. No parasites have ever been reported for this species and only 1 ectoparasite is described for the entire genus. In the current study ectoparasites were collected from individuals captured at 3 localities in South Africa and Namibia to document the ectoparasite community of F. damarensis, investigate their aggregation patterns, and evaluate the influence of season on ectoparasite burden. A total of 2,071 arthropods from 9 mite taxa and 1 louse species (Eulinognathus hilli) were collected from 293 hosts sampled. Of these, 5 mite species (Androlaelaps scapularis, Androlaelaps capensis, Androlaelaps tauffliebi, Radfordia sp., and unidentified chiggers) and the louse were parasites while the remainder was soil mites. All ectoparasites were highly aggregated and the species richness as well as the prevalence and abundance of 4 of them were significantly greater in summer compared to winter, possibly as a result of seasonal changes in rainfall patterns affecting the ectoparasites, host behavior, or both. PMID:26249137

  16. Insecticide dissipation from soil and plant surfaces in tropical horticulture of southern Benin, West Africa.

    PubMed

    Rosendahl, Ingrid; Laabs, Volker; Atcha-Ahowé, Cyrien; James, Braima; Amelung, Wulf

    2009-06-01

    In Sub-Saharan Africa, horticulture provides livelihood opportunities for millions of people, especially in urban and peri-urban areas. Although the vegetable agroecosystems are often characterized by intensive pesticide use, risks resulting therefrom are largely unknown under tropical horticultural conditions. The objective of this study therefore was to study the fate of pesticides in two representative horticultural soils (Acrisol and Arenosol) and plants (Solanum macrocarpon L.) after field application and thus to gain first insight on environmental persistence and dispersion of typical insecticides used in vegetable horticulture in Benin, West Africa. On plant surfaces, dissipation was rapid with half lives ranging from 2 to 87 h (alpha-endosulfan < beta-endosulfan < deltamethrin). Soil dissipation was considerably slower than dissipation from plant surfaces with half-lives ranging from 3 (diazinon) to 74 d (total endosulfan), but persistence of pesticides in soil was still reduced compared to temperate climates. Nevertheless, for deltamethrin and endosulfan, a tendency for mid-term accumulation in soil upon repeated applications was observed. The soil and plant surface concentrations of the metabolite endosulfan sulfate increased during the entire trial period, indicating that this compound is a potential long-term pollutant even in tropical environments. PMID:19513446

  17. HIV-Related Discrimination among Grade Six Students in Nine Southern African Countries

    PubMed Central

    Maughan-Brown, Brendan; Spaull, Nicholas

    2014-01-01

    Background HIV-related stigmatisation and discrimination by young children towards their peers have important consequences at the individual level and for our response to the epidemic, yet research on this area is limited. Methods We used nationally representative data to examine discrimination of HIV-positive children by grade six students (n = 39,664) across nine countries in Southern Africa: Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe. Descriptive statistics are used to compare discrimination by country, gender, geographic location and socioeconomic status. Multivariate logistic regression is employed to assess potential determinants of discrimination. Results The levels and determinants of discrimination varied significantly between the nine countries. While one in ten students in Botswana, Malawi, South Africa and Swaziland would “avoid or shun” an HIV positive friend, the proportions in Lesotho, Mozambique, Zambia and Zimbabwe were twice as high (approximately 20%). A large proportion of students believed that HIV positive children should not be allowed to continue to attend school, particularly in Zambia (33%), Lesotho (37%) and Zimbabwe (42%). The corresponding figures for Malawi and Swaziland were significantly lower at 13% and 12% respectively. Small differences were found by gender. Children from rural areas and poorer schools were much more likely to discriminate than those from urban areas and wealthier schools. Importantly, we identified factors consistently associated with discrimination across the region: students with greater exposure to HIV information, better general HIV knowledge and fewer misconceptions about transmission of HIV via casual contact were less likely to report discrimination. Conclusions Our study points toward the need for early interventions (grade six or before) to reduce stigma and discrimination among children, especially in schools situated in rural areas and poorer

  18. HIV Prevalence, Risks for HIV Infection, and Human Rights among Men Who Have Sex with Men (MSM) in Malawi, Namibia, and Botswana

    PubMed Central

    Baral, Stefan; Trapence, Gift; Motimedi, Felistus; Umar, Eric; Iipinge, Scholastika; Dausab, Friedel; Beyrer, Chris

    2009-01-01

    Background In the generalized epidemics of HIV in southern Sub-Saharan Africa, men who have sex with men have been largely excluded from HIV surveillance and research. Epidemiologic data for MSM in southern Africa are among the sparsest globally, and HIV risk among these men has yet to be characterized in the majority of countries. Methodology A cross-sectional anonymous probe of 537 men recruited with non-probability sampling among men who reported ever having had sex with another man in Malawi, Namibia, and Botswana using a structured survey instrument and HIV screening with the OraQuick© rapid test kit. Principal Findings The HIV prevalence among those between the ages of 18 and 23 was 8.3% (20/241); 20.0% (42/210) among those 24–29; and 35.7% (30/84) among those older than 30 for an overall prevalence of 17.4% (95% CI 14.4–20.8). In multivariate logistic regressions, being older than 25 (aOR 4.0, 95% CI 2.0–8.0), and not always wearing condoms during sex (aOR 2.6, 95% CI 1.3–4.9) were significantly associated with being HIV-positive. Sexual concurrency was common with 16.6% having ongoing concurrent stable relationships with a man and a woman and 53.7% had both male and female sexual partners in proceeding 6 months. Unprotected anal intercourse was common and the use of petroleum-based lubricants was also common when using condoms. Human rights abuses, including blackmail and denial of housing and health care was prevalent with 42.1% (222/527) reporting at least one abuse. Conclusions MSM are a high-risk group for HIV infection and human rights abuses in Malawi, Namibia, and Botswana. Concurrency of sexual partnerships with partners of both genders may play important roles in HIV spread in these populations. Further epidemiologic and evaluative research is needed to assess the contribution of MSM to southern Africa's HIV epidemics and how best to mitigate this. These countries should initiate and adequately fund evidence-based and targeted HIV

  19. Progress and Challenges for Implementation of the Common Market for Eastern and Southern Africa Policy on Biotechnology and Biosafety.

    PubMed

    Waithaka, Michael; Belay, Getachew; Kyotalimye, Miriam; Karembu, Margaret

    2015-01-01

    In 2001, the Meeting of the COMESA Ministers of Agriculture raised concerns that proliferation of genetically modified organisms (GMOs) could impact significantly on trade and food security in the region. This triggered studies on a regional approach to biotechnology and biosafety policy in Eastern and Southern Africa. The studies and stakeholder consultations revealed that farm incomes would increase if they switched from conventional varieties of cotton and maize to genetically modified (GM) counterparts. Commercial risks associated with exports to GM sensitive destinations, e.g., EU were negligible. Intra-regional trade would be affected since exports of GM sensitive commodities, such as maize, cotton, and soya bean, mainly go to other African countries. These findings justified the need to consider a regional approach to biosafety and led to the drafting of a regional policy in 2009. The draft policies were discussed in regional and national workshops between 2010 and 2012 for wider ownership. The workshops involved key stakeholders including ministries of agriculture, trade, environment, national biosafety focal points, biosafety competent authorities, academia, seed traders, millers, the media, food relief agencies, the industry, civil society, competent authorities, and political opinion leaders. The COMESA Council of Ministers in February 2014 adopted the COMESA policy on biotechnology and biosafety that takes into account the sovereign right of each member state. Key provisions of the policy include recognition of the benefits and risks associated with GMOs; establishment of a regional-level biosafety risk-assessment system; national-level final decision, and capacity building assistance to member states. The policies are the first regional effort in Africa to develop a coordinated mechanism for handling biosafety issues related to GMO use. A regional approach to biotechnology and biosafety is expected to foster inter-country cooperation through the

  20. Progress and Challenges for Implementation of the Common Market for Eastern and Southern Africa Policy on Biotechnology and Biosafety

    PubMed Central

    Waithaka, Michael; Belay, Getachew; Kyotalimye, Miriam; Karembu, Margaret

    2015-01-01

    In 2001, the Meeting of the COMESA Ministers of Agriculture raised concerns that proliferation of genetically modified organisms (GMOs) could impact significantly on trade and food security in the region. This triggered studies on a regional approach to biotechnology and biosafety policy in Eastern and Southern Africa. The studies and stakeholder consultations revealed that farm incomes would increase if they switched from conventional varieties of cotton and maize to genetically modified (GM) counterparts. Commercial risks associated with exports to GM sensitive destinations, e.g., EU were negligible. Intra-regional trade would be affected since exports of GM sensitive commodities, such as maize, cotton, and soya bean, mainly go to other African countries. These findings justified the need to consider a regional approach to biosafety and led to the drafting of a regional policy in 2009. The draft policies were discussed in regional and national workshops between 2010 and 2012 for wider ownership. The workshops involved key stakeholders including ministries of agriculture, trade, environment, national biosafety focal points, biosafety competent authorities, academia, seed traders, millers, the media, food relief agencies, the industry, civil society, competent authorities, and political opinion leaders. The COMESA Council of Ministers in February 2014 adopted the COMESA policy on biotechnology and biosafety that takes into account the sovereign right of each member state. Key provisions of the policy include recognition of the benefits and risks associated with GMOs; establishment of a regional-level biosafety risk-assessment system; national-level final decision, and capacity building assistance to member states. The policies are the first regional effort in Africa to develop a coordinated mechanism for handling biosafety issues related to GMO use. A regional approach to biotechnology and biosafety is expected to foster inter-country cooperation through the

  1. Magnetotelluric measurements across the southern Barberton greenstone belt, South Africa: data improving strategies and 2-D inversion results

    NASA Astrophysics Data System (ADS)

    Kutter, S.; Chen, X.; Weckmann, U.

    2011-12-01

    Magnetotelluric (MT) measurements in areas with electromagnetic (EM) noise sources such as electric fences, power and railway lines pose severe challenges to the standard processing procedures. In order to significantly improve the data quality advanced filtering and processing techniques need to be applied. The presented 5-component MT data set from two field campaigns in 2009 and 2010 in the Barberton/Badplaas area, South Africa, was acquired within the framework of the German-South African geo-scientific research initiative Inkaba yeAfrica. Approximately 200 MT sites aligned along six profiles provide a good areal coverage of the southern part of the Barberton Greenstone Belt (BGB). Since it is one of the few remaining well-preserved geological formations from the Archean, it presents an ideal area to study the tectonic evolution and the role of plate tectonics on Early Earth. Comparing the electric properties, the surrounding high and low grade metamorphic rocks are characteristically resistive whereas mineralized shear zones are possible areas of higher electrical conductivity. Mapping their depth extension is a crucial step towards understanding the formation and the evolution of the BGB. Unfortunately, in the measurement area numerous noise sources were active, producing severe spikes and steps in the EM fields. These disturbances mainly affect long periods which are needed for resolving the deepest structures. The Remote Reference technique as well as two filtering techniques are applied to improve the data in different period ranges. Adjusting their parameters for each site is necessary to obtain the best possible results. The improved data set is used for two-dimensional inversion studies for the six profiles applying the RLM2DI algorithm by Rodi and Mackie (2001, implemented in WinGlink). In the models, areas with higher conductivity can be traced beneath known faults throughout the entire array along different profiles. Resistive zones seem to correlate

  2. Accretionary history of the Archean Barberton Greenstone Belt (3.55-3.22 Ga), southern Africa

    NASA Technical Reports Server (NTRS)

    Lowe, D. R.

    1994-01-01

    The 3.55-3.22 Ga Barberton Greenstone Belt, South Africa and Swaziland, and surrounding coeval plutons can be divided into four tectono-stratigraphic blocks that become younger toward the northwest. Each block formed through early mafic to ultramafic volcanism (Onverwacht Group), probably in oceanic extensional, island, or plateau settings. Volcanism was followed by magmatic quiescence and deposition of fine-grained sediments, possibly in an intraplate setting. Late evolution involved underplating of the mafic crust by tonalitic intrusions along a subduction-related magmatic arc, yielding a thickened, buoyant protocontinental block. The growth of larger continental domains occurred both through magmatic accretion, as new protocontinental blocks developed along the margins of older blocks, and when previously separate blocks were amalgamated through tectonic accretion. Evolution of the Barberton Belt may reflect an Early Archean plate tectonic cycle that characterized a world with few or no large, stabilized blocks of sialic cru