Department of Environmental Sciences

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    14C dating of organic residue and carbonate from stromatolites in Etosha Pan, Namibia: 14C reservoir effect, correction of published ages, and evidence of >8-m-deep lake during the late pleistocene
    (2013) Hipondoka, Martin; Brook, George A.; Railsback, Bruce L.; Marais, Eugene
    Lacustrine stromatolites are layered accretionary structures formed in shallow water by cyanobacteria. They are a precise indicator of high lake limits and their morphology and structure provide an insight into paleoenvironments of the time. Previous research on lacustrine stromatolites from Etosha Pan in Namibia based on radiocarbon ages of carbonates were close to the limit of the method and did not account for any possible 14C reservoir effect. The ages were used to suggest that the basin was not extensively flooded during the last 40,000 yr. To assess the reservoir effect, the age characteristics of a stromatolite from Poacher’s Point were investigated by 14C dating both carbonate and organic residue from samples at different depths in the deposit. The ~15-cm-diameter stromatolite was separated into 12 zones from the center to the edge and block samples were cut from each zone; the carbonate and residual organic residue were dated separately. The carbonate ages ranged from 34,700 to 24,700 14C yr BP and the organic ages from 15,700 to 2500 14C yr BP. Ages generally increased with increasing distance from the surface of the deposit. We believe that the organic ages are an accurate estimate of the stromatolite’s age, while the much older carbonate ages reflect incorporation of old carbon from limestone bedrock and ancient calcrete introduced by stream and spring flow. Excluding the 2 oldest organic ages (15,700 and 13,600 14C yr BP), which may reflect contamination by older organic material washed into the lake during flooding, a linear regression relationship between carbonate and organic ages indicates that the reservoir effect on carbonate ranges up to ~24,000 14C yr BP but decreases slightly as the true age of the deposit increases. This regression relationship was used to correct 2 finite carbonate ages for stromatolites from Pelican Island obtained in the early 1980s, which together with our new organic age for a stromatolite from Andoni Bay, document a >8-m-deep lake in Etosha Pan during the Late Pleistocene, at and prior to ~34,000–26,000 cal yr BP. The organic carbon ages from the Poacher’s Point stromatolite suggest prolonged lacustrine conditions during the early to middle Holocene (8000–6600 cal yr BP) but not to the extent seen during the Late Pleistocene
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    Analysis of the impact of demographic and economic factors on internet services satisfaction levels in Windhoek, Namibia
    (University of Namibia, 2018) Tubulingane, Booysen Sabeho
    The study focused on analysing geospatial internet customer satisfaction levels, using the Geographic Information System (GIS) technology. The aim of the study was to investigate how demographic and economic factors influence satisfaction levels. The study followed a quantitative design and employed the systematic sampling method to select a sample of 248 potential internet users. A structured self-administered questionnaire was used to collect data from selected samples. The statistical and spatial analyses were conducted in such a way that results were comparable between areas from low, to high income levels. Low income suburbs were represented by Greenwell Matongo Ext 1 (informal settlement) and Grysblock Ext 1 (formal settlement). Moreover, middle to high income areas were represented by Pioneers Park Ext 1 (formal settlement). The study findings revealed that internet users in low income areas especially in the informal settlement experienced high level of dissatisfaction with internet services compared to the middle to high income area. Moreover, males in the middle to high income area made up the majority of internet users. Within the lower income areas, use of the internet was predominantly by users who were less than 30 years old whilst in the middle to high income area, people who were aged between 31 and 40 years used the internet more than people aged less than 30 years. The majority of internet users earned a gross monthly income of less than N$ 5000 (US$ 1 = N$ 11.6) and had a secondary school level education. Satisfaction levels noted differ noticeably across the various demographics. The lowest satisfaction scores were dominated by female internet users who completed grade 12. The highest satisfaction scores were mostly reported by male internet users who had a tertiary education at diploma or degree levels. The lowest satisfaction scores were dominated by internet users earning less than N$ 5000 and were residing in low income areas. The highest satisfaction scores were mostly articulated by internet users residing in the middle to high income area. There is need for Telecommunication Companies in Namibia to introduce more fixed post-paid internet services especially in low income areas of Windhoek and other areas of Namibia. Fixed post-paid internet services were discovered to be associated with higher internet satisfaction levels compared to mobile prepaid internet services. Additionally, the Communications Regulatory Authority of Namibia (CRAN) need to consider introducing an application which assists users to monitor and report poor customer service
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    Assessing the impact of wildlife on vegetation cover change, Northeast Namibia, based on MODIS satellite imagery (2002–2021)
    (Sensors, 2022) Gbagir, Augustine-Moses Gaavwase; Sikopo, Colgar Sisamu; Matengu, Keneth K.
    Human–wildlife conflict in the Zambezi region of northeast Namibia is well documented, but the impact of wildlife (e.g., elephants) on vegetation cover change has not been adequately addressed. Here, we assessed human–wildlife interaction and impact on vegetation cover change. We analyzed the 250 m MODIS and ERA5 0.25 0.25 drone and GPS-collar datasets. We used Time Series Segmented Residual Trends (TSS-RESTREND), Mann–Kendall Test Statistics, Sen’s Slope, ensemble, Kernel Density Estimation (KDE), and Pearson correlation methods. Our results revealed (i) widespread vegetation browning along elephant migration routes and within National Parks, (ii) Pearson correlation (p-value = 5.5 10􀀀8) showed that vegetation browning areas do not sustain high population densities of elephants. Currently, the Zambezi has about 12,008 elephants while these numbers were 1468, 7950, and 5242 in 1989, 1994, and 2005, respectively, (iii) settlements and artificial barriers have a negative impact on wildlife movement, driving vegetation browning, and (iv) vegetation greening was found mostly within communal areas where intensive farming and cattle grazing is a common practice. The findings of this study will serve as a reference for policy and decision makers. Future studies should consider integrating higher resolution multi-platform datasets for detailed micro analysis and mapping of vegetation cover change.
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    Assessing the potential of agritourism at Neudamm, Namibia
    (University of Namibia, 2023) !Gaeb, Manfred Donavon
    The share of the agricultural Gross Domestic Product (GDP) in Namibia is lower than that of the average Sub-Saharan Africa. Correspondingly, is the share of agricultural labour force, which has also, been declining since the country’s independence (Mushendami, Biwa and Gaomab 2008). The University of Namibia (UNAM) experienced this reality, primarily, through potential of income generating opportunity at Neudamm Campus. As a result of this precarious condition, and the declining of UNAM’s government subsidy, the university had to explore alternative income streams. One such alternative avenue is the agritourism opportunity at Neudamm. Very few studies have so far assessed agritourism factors of success in global north whilst global south lack such studies. This gap in literature in assessing agritourism factors of success in the global south necessitated this study. The research concluded firstly, that economic factors are not the only determining factors of successful agritourism but also social factors. Secondly, the findings established that Neudamm suffers from several shortcomings and therefore, potential viable agritourism cannot be achieved without addressing those shortcomings. Thirdly, critical success factors of agritourism were found to be natural bonding dynamics of various forms of capital. As a result, the study recommended nomination of Neudamm as a place of heritage importance due to its historical importance. Furthermore, policy directives such as Affirmative Action Loan Scheme (AALS) and National Agricultural Credit Program (NACP) need urgent review thirty two years after Namibia’s independence, to foster national reconciliation. Additionally, the implementation of agritourism concept at farm Neudamm is fervently advised by addressing shortcomings and adding tangible visionary stage for the TALC model during agritourism destination development process is proposed.
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    Assessment of floodwater harvesting infrastructures in the Namibian Cuvelai-Etosha basin
    (University of Namibia, 2020) Niipare, Emeritha
    The Cuvelai-Etosha Basin lies in north-central Namibia and due to the prevailing climatic situation, the basin is dominated by strong seasonal and annual variations of either very dry conditions with drought or heavy flooding in certain years. A growing population in the Cuvelai-Etosha Basin has resulted in increased demand for water for daily use and agricultural activities. Floodwater Harvesting Infrastructures are considered to be a more effective way to solve those problems. Hence the current status of the initiatives taken to harvest floodwater for use in the dry seasons needs to be determined by means of remote sensing, secondary data and field validation. The main objective of the study was to assess the condition and performance of Floodwater Harvesting Infrastructures in the Cuvelai-Etosha Basin. The Ministry of Agriculture, Water and Forestry constructed 34 earth dams in this Basin from 2008 to 2011. Out of these newly constructed earth dams, 18 were randomly selected for the study. The research design was based on using both qualitative and quantitative data on a completely randomised basis. Sentinel data was used to identify the water bodies by means of remote sensing. Information was gathered by means of structured interviews from the locals or people acquainted with the sites. The results from the interviews taken among 96% of the participants showed that the highest usage of earth dams is livestock watering while few people use them for irrigation purposes. Due to sedimentation in the earth dams, depth has reduced and surficial area has increased; hence the dams can no longer retain the quality and quantity of water they were designed for. In conclusion, the method developed from GIS successfully identified 94% of the existing earth dams.
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    An assessment of the trends in population abundance and spatial distribution of roan antelope (Hippotragus equinus) and sable antelope (Hippotragus niger) in the greater Waterberg plateau complex, North-central, Namibia
    (University of Namibia, 2022) Alfeus, Martha
    Understanding factors affecting the demographic status and spatial distribution of large mammals is of major relevance in wildlife conservation and management. This is particularly the case for the roan (Hippotragus equinus) and the sable (Hippotragus niger) populations in the Waterberg Plateau Park (WPP) whose growth appears to have been suppressed since 1994, after being introduced in 1975 and 1980, respectively. The lack of scientific assessments on potential factors influencing their growth and spatial distribution has been a major challenge confronting their management in the WPP, which is the aim of this study. The study used the Generalized Additive Modelling and State Space Models to assess trends in the abundance of roan and sable between 1975 and 2019 in the WPP based on historical aerial count data. Additionally, occupancy modelling and detection probability was conducted to assess the influence of site and detection covariates on their spatial distribution in the Waterberg Plateau Farm based on the camera trapping data collected during the wet and dry seasons. The study estimated with uncertainty a negative population growth for roan (r = - 0.02 ± 0.06, CI95 = -0.13 – 0.09) and a zero-population growth for the sable (r = 0.00 ± 0.08, CI95 = -0.14 – 0.16). These growth trajectories tend to be positively influenced by annual rainfall, and the occasional auctioning, and the introduction of individuals. Contrary, it was insignificantly but negatively influenced by the low-lagged rainfall and the increase of the buffalo population. Occupancy modelling showed that roan distribution is significantly influenced by the co-occurrence of sable both during the wet and the dry seasons. Sable distribution was positively influenced by forage and the presence/absence of leopard during the wet season while positively influenced by the presence/absence of waterhole during the dry season. The cumulative effect of these variables is likely to have resulted in the reduction of the survival and reproduction rate as these antelopes are unable to escape the semi-closed isolated study areas. Future interventions involving the introduction of these species outside their native ranges should be careful thought, and must consider the potential impacts of climate change to improve the success of this management strategy.
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    A CFD study of wind patterns over a desert dune and the effect on seed dispersion
    (Springer Netherlands, 2012) Joubert, Eugene C.; Harms, Thomas M.; Muller, Annethea A.; Hipondoka, Martin; Henschel, Joe R.
    In the Namib Desert seed distribution is greatly influenced by wind patterns. Existing literature regarding wind patterns over dunes focuses on two-dimensional simulations of flow over simplified dune structures. The three-dimensional geometries of the sand dunes suggests far more complex flow features exist, which are not captured by two-dimensional simulations. Computational fluid dynamics (CFD) was used to reproduce the three-dimensional near surface wind patterns around a dune with the aim to learn more about seed distribution. Field work included terrain mapping, wind speed, direction and temperature metering. The CFD results show the expected two-dimensional flow features of high pressure at the dune toe, low pressure at the crest and flow acceleration up windward slope. Also observed are some three-dimensional flow features such as a spiral vortex near the crest and transverse flow due to crest-line curvature of the dune. It was also observed how the wall shear stress differs due to the three-dimensional shape of the dune. The wall shear stress suggests that seed accumulation is more likely to occur behind trailing (down-wind) crest edges. Particle tracking showed how seeds tend to move over the dune crest and recirculate towards the crest on the lee-side. The study showed that adding the third dimension makes the simulations more complex, adds to computational requirements and increases simulation time but also provides vital flow information which is not possible with two-dimensional simulations.
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    Changes in numbers of Lesser Kestrels Falco naumanni and Amur Falcons F. amurensis at a winter roost in Lesotho
    (African Bird Club, 2012) Kopij, Grzegorz
    Over the last 20 years drastic changes have been recorded in the composition of a flock of Lesser Kestrels Falco naumanni and Amur Falcons F. amurensis at a roost on the campus of the National University of Lesotho at Roma. Numbers of the latter have increased, while those of the former species have dramatically decreased. Changes in the number of Amur Falcons recorded in February – March suggest that their southward migration continues until early February and soon thereafter a departure north starts, with most birds vacating the roost in the first half of March. The earliest arrival of Lesser Kestrel was 26 October, the latest departure 9 April. The earliest arrival date of Amur Falcon was 19 December, the latest departure date 7 April. Early-morning departure from the roost lasted for up to 40 minutes, but most birds left during the first 5–10 minutes
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    The changing climate and human vulnerability in north-central Namibia
    (2016) Angula, Margaret; Kaundjua, Maria B.
    North-central Namibia is more vulnerable to effects of climate change and variability. Combined effects of environmental degradation, social vulnerability to poverty and a changing climate will compromise subsistence farming in north-central Namibia (NCN). This will make subsistence and small-scale farmers in the region more vulnerable to projected changes in the climate system. Thus, the aim of this article was to examine factors contributing to subsistence farmers’ vulnerability to impacts of climate change. The article further discusses different aspects of human vulnerability and existing adaptation strategies in response to impacts of climate related disasters experienced over the past three to four decades in NCN. Qualitative and quantitative research approaches and methodology were employed to obtain information from subsistence farmers in north-central Namibia. The sociodemographic characteristics of Ohangwena, Oshana and Omusati Region reveals high levels of unemployment, high adult and elderly population and high dependency on agricultural livelihood system. These indicators help understand levels of household vulnerability. The study concludes that households interviewed revealed low levels of adaptive capacity due to exposure to climate risks and combined effects of social, political and cultural factors. This article provided an understanding that is required to inform the adaptation pathways relevant for NCN.
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    Chronology of sand ridges and the Late Quaternary evolution of the Etosha Pan, Namibia
    (2014) Hipondoka, Martin; Mauz, B.; Kempf, Jurgen; Packman, S.; Chiverrell, R.C.; Bloemendal, J.
    Etosha Pan, situated at the southern border of tropical Africa, is a vast endorheic plain in Namibia's semi-arid north. The most recent studies agree that the pan was the floor of a former lake with varying water levels. Here we explored this idea further by investigating the link between lake-level change and records of late Pleistocene and Holocene climate change. The varying lake levels were inferred through sediment analysis and optical dating of sand deposits that form ridges parallel to the current shore along the northern and western margins of the pan. Our results support the view that the sand ridges are shoreline deposits of an evaporitic lake. The ridges result from the interplay between intermittent river discharge and riverine sediment supply from the north, prevailing north-easterly wind and shore-parallel waves. Therefore they are a proxy for former levels of a perennial lake. We infer higher levels during the late Pleistocene and a drastic drop shortly after 10 ka. Since around 8 ka Etosha Pan was covered by a shallow water body. This lake water-level reconstruction is not in line with the histories of ITCZ migration and strength of Benguela current upwelling. We confirm that the linkages between the evolution of the Etosha Pan and the climate mechanisms driving hydrological changes in subtropical southwest Africa are poorly resolved and need further investigation.
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    Consumptive forest use and spatio-temporal abundance of wildlife in George Mukoya and Muduva Nyangana Community Conservancy in Northern Namibia
    (University of Namibia, 2024) Liyeke, Miriam Mambo; Rutina, L. P.
    Forests are important to people because they provide socio-economic and ecological goods and services such as the use of poles for building materials and income through selling. Studies have shown that the degradation or loss of forests has a direct impact on wildlife. In rural areas of Namibia, some forests on communal land are managed by the local communities to provide socio-economic benefits. If not well managed and the use is not sustainable (inappropriate use), may undermine the long-term ecological value of forest resources including wildlife. The Khaudum north complex conservancies (George Mukoya and Muduva Nyangana) were established in 2005 and community forests were gazetted in 2010. In the year 2012, the government of Namibia through the Ministry of Environment Forestry and Tourism integrated the wildlife conservancies and community forests, with the aim of harmonising the two land uses. Since then there were no studies to assess the community forest use on wildlife species and their habitat thus the need to conduct this study. This study used both quantitative and qualitative methods to collect data. Data on wildlife species abundance and distributions were collected from conservancies’ event books and game counts. Interviews were used to gather community perceptions on the consequences of their livelihood strategies on wildlife. A sample size of 293 respondents was obtained from the two conservancies. To assess the change in wildlife species abundance, the regression analysis with yearly wildlife group size as a dependent variable was applied. The distance from nearby settlements, fire intensity, and vegetation cover change as continuous independent variables; and conservancy (George Mukoya and Muduva Nyangana), species category (carnivores and herbivores), land use (multiple use and wildlife exclusive zones) and season (dry and wet) as categorical variables. Satellite images were used to analyse vegetation cover change and accumulated fire intensity using change detection analysis and empirical Bayesian kriging interpolation. Average group size means, and standard errors were calculated and used to determine the associations ii among variables. Contingency tables were used to analyse respondents’ perceptions of the influences of livelihood strategies and major socio-economic activities on wildlife. Generally, results showed a decrease in wildlife numbers in the study area between 2013 and 2017 (P <0.001). This was positively associated with vegetation change (P =0.032) and species category (P < 0.001), negatively by distance from settlement (P = 0.004) and land use (P < 0.001), but was not fire intensity (P = 0.714) and locality (conservancy) (P = 0.170). Carnivore density distribution was evenly spread in relation to distance from settlements, fire intensity, and vegetation change but was more in a wildlife-exclusive zone than the multiple-use zone. Herbivore distribution was denser in the wildlife-exclusive zone, more in areas where vegetation cover was high, and increased with increasing distance from settlements, but was not influenced by fire intensity. In both conservancies, the majority of respondents were either dependent on crop production (53%) or a combination of crop production and livestock (30%), with only 18% depending on other livelihood strategies. When asked what is the impact of their livelihood strategies on wildlife and its habitat, 75%, 17%, and 8% of the respondents said there no impact, impact, or no awareness, respectively. When the community was asked, what is the impact of the services they get from forestry on wildlife and its habitat, 73% of the respondents said there was no impact whereas 27% indicated that there was a significant impact. The study showed that the communities of George Mukoya and Muduva Nyangana are aware of the conservation issues in their areas and can manage wildlife successfully themselves.
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    Could China’s journey of malaria elimination extend to Africa?
    (Infectious Diseases of poverty, 2022) Wang, Duoquan; Lv, Shan; Matengu, Keneth K.
    World Health Organization (WHO) certified China malaria-free on June 30, 2021, which brightens the goal of global malaria elimination efforts. China contributed its unique innovations to the global community: Artemisinin, discovered by Tu Youyou, has saved millions of lives globally; the “1-3-7” norm developed in 2012, has been adapted in the local contexts of countries in the Southeast Asia and Africa. How to the targets of Global Technical Strategy for Malaria (GTS) 2016−2030. By looking into the malaria control phase, towards elimination phase from 1960 to 2011 in sub Saharan Africa and China, we found that the gap in malaria burden will widen unless the interventions in Africa are enhanced. It is imperative to identify the key China–Africa cooperation areas on malaria control and elimination, so that synergized efforts could be pooled together to help African countries achieve the elimination goal. The practices from China malaria control and elimination efforts could be leveraged to fast-track malaria elimination efforts in Africa, which makes it possible that the China’s journey of malaria elimination extends to Africa.
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    A cross sectional comparison of chemical treatment on plant biodiversity at Neudamm farm, Khomas region
    (University of Namibia, 2020) Shigwedha, Diina
    This study determined the impacts of chemical application on plant biodiversity in comparison to the control ecosystems over a three-year period at Neudamm farm in Khomas Region, Namibia. In this study, for herbaceous plant sampling, a total of 40 (1m2) quadrats were randomly laid in each of the three chemically treated sites (treated in 2015, 2016 and 2017) and in the control site to record the herbaceous plant density, plant species composition, dry matter production and ground cover. For woody plant sampling, a total of three 250 m2 belt transects were randomly laid in each of the three chemically treated sites and also in the control. All woody plants in the belt transects were identified, measured and recorded for plant height and canopy diameters. For soil sampling, a total of ten soil samples were collected from the three the belt transects in each of the three chemically treated sites and also in the control at a depth of 15 cm using a soil auger. The soil was analysed for pH, soil minerals, organic carbon and organic matter. A total of 20 grass species were identified in all the four sites, of which 55% were perennials and 45% were annuals. The mean total grass tuft density was significantly higher (P < 0.05) in control and the chemically treated sites of 2015 and 2017, but lower in the chemically treated site of 2016. Herbaceous biomass production was significantly higher (P < 0.05) in chemically treated site of 2015 (975 Kg DM ha-1), followed by 2016 (925 Kg DM ha-1) and least in the other two sites. The chemically treated site of 2016 had greater (P < 0.05) ground cover percentage than the other three treatment sites. The total woody plant density was significantly higher (P < 0.05) in the control (14 160 TE ha-1) than in all three similar chemically treated sites. The canopy cover percentage and woody plant densities in all woody height categories were higher (P < 0.05) in the control and the chemically treated site of 2017, than in the other two sites. The chemically treated site of 2015 had the highest amount of soil pH (6.06), followed by the control (5.61) and the chemical treatment site of 2017 (5.5), and they were statistically significant (P < 0.05). The organic carbon and organic matter percentages were significantly (P < 0.05) higher in the chemically treated site of 2015 than in all the other sites. The soil in the chemically treated site of 2016 had the highest Ca (551 ppm), K (197.3 ppm), Mg (76 ppm), P (23.3) contents, followed by the site of 2015 than in the control. This study concluded that chemical treatments have impacted on the plant biodiversity of the treated rangelands by improving the herbaceous plant species, biomass yields, reduced bush density and enhanced the soil chemical properties.
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    Density and abundance estimation of unmarked ungulates using camera traps in the Mudumu National Park, Namibia
    (European Journal of Wildlife Research, 2024) Nauyoma, LineekelaOmwene T; Warbington, Camille H; Azevedo, Fernanda C; Lemos, Frederico G; Sequeira, Fernando; Fabiano, Ezequiel C
    Density and abundance estimates are critical to effective wildlife management and are essential for monitoring population trends and setting effective quotas for harvesting. Management of roan (Hippotragus equinus) and sable (H. niger) antelopes in Mudumu National Park (MNP), Namibia, is challenging because they are elusive, naturally unmarked, and believed to occur at low densities. The species are threatened by habitat fragmentation, human population growth, and illegal hunting, and reliable density and abundance estimates have not been quantified, hampering management and conservation plans. Our objective was to estimate roan and sable densities and abundances using the time in front of the camera model (TIFC) and the Poisson-binomial N-mixture model (PB), respectively. We also evaluated the effects of environmental and ecological variables on roan and sable abundance. We used data from two camera trap surveys conducted between March and September 2021 in the MNP. Results showed that the TIFC model provided low-density estimates of 1.62 (95% CI 1.61–1.64) roans/km2 and 2.46 (95% CI 2.42–2.50) sables/km2 , consistent with trends reported in Africa where these species occur at low densities. In addition, the total abundance of roans and sables in the MNP from the PB model were 57 and 242, respectively. Higher roan abundance occurred in sites with higher grass cover. This study provides the first accurate camera trap-derived density and abundance estimates for roan and sable in the MNP, which will be critical for developing comprehensive conservation programs and strategies that are likely to reduce the risk of extinction for both species
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    The development and evolution of Etosha Pan, Namibia
    (University of Wurzburg, 2005) Hipondoka, Martin
    This study explores and examines the geomorphology of a large endorheic basin, approximately twice the size of Luxemburg, situated in the Etosha National Park, Namibia. The main focus is directed on how and when this depression, known as Etosha Pan, came into being. The opposing view emerged in the 1980s and gained prominence in the 1990s. This view assumed that there were an innumerable number of small pans on the then surface of what later to become Etosha Pan. Since the turn of the Pliocene to Early Pleistocene, these individual pans started to experience a combined effect of fluvial erosion during the rainy season and wind deflation during the dry period. The climatic regime during that entire period was postulated to be semi-arid as today. This climatic status was used to rule out any existence of a perennial lake within the boundary of Etosha since the Quaternary. Ultimately, these denudational processes, taking place in a seasonal rhythm, caused the individual pans to deepen and widen laterally into each other and formed a super-pan that we call Etosha today. Thus the Kunene River had no role to play in the development of the Etosha Pan according to this model. However, proponents of this model acknowledged that the Kunene once fed into the Owambo Basin and assigned the end of the Tertiary to the terminal phase of that inflow. Geomorphological investigation was complemented and guided primarily by the application and interpretation of satellite-derived information. Etosha Pan has attracted scientific investigations for nearly a century. Unfortunately, their efforts resulted into two diverging and mutually exclusive views with respect to its development. The first and oldest view dates back to the 1920s. It hypothesized Etosha Pan as a desiccated palaeolake which was abandoned following the river capture of its major fluvial system, the Kunene River. The river capture was assumed to have taken place in the Pliocene/Early Pleistocene. In spite of the absence of fluvial input that the Kunene contributed, the original lake was thought to have persisted until some 35 ka ago, long after the Kunene severed its ties with the basin. The current size of the basin and its playa status was interpreted to have resulted from deteriorating climatic conditions. The opposing view emerged in the 1980s and gained prominence in the 1990s. This view assumed that there were an innumerable number of small pans on the then surface of what later to become Etosha Pan. Since the turn of the Pliocene to Early Pleistocene, these individual pans started to experience a combined effect of fluvial erosion during the rainy season and wind deflation during the dry period. The climatic regime during that entire period was postulated to be semi-arid as today. This climatic status was used to rule out any existence of a perennial lake within the boundary of Etosha since the Quaternary. Ultimately, these denudational processes, taking place in a seasonal rhythm, caused the individual pans to deepen and widen laterally into each other and formed a super-pan that we call Etosha today. Thus the Kunene River had no role to play in the development of the Etosha Pan according to this model. However, proponents of this model acknowledged that the Kunene once fed into the Owambo Basin and assigned the end of the Tertiary to the terminal phase of that inflow.
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    Development of mining settlements in Namibia: An investigation into prospects for Rosh Pinah, Klein Aub and Tsumeb
    (University of Namibia, 2015) Stankevica, Vita
    The dissertation examined the development and potential prospects of three diverse mining settlements in Namibia - Rosh Pinah, Klein Aub, and Tsumeb. It is a case study in settlement geography aiming to investigate problem areas and their potential solution towards sustaining people-centred urban stability, growth and development, linked to the assistance of private-public local and regional development planning in an environment of global mining competition. The integrative literature review revealed that publications on Namibia predominantly offer a descriptive account of past and present mining settlements in the country. The focus of this study on prospects for mining settlements in the context of local and regional urban development planning evolved together with the revitalised integration of Namibia’s mining industry in global markets. Refocussing the role of Namibian mining settlements on spatial development disclosed the need for research in problem formations, processes, perspectives and concepts to assist in securing knowledge and capacity for future development with or without mining activities. The methodology was based on five concepts, namely (i) Christaller’s Central Place theory (1933) which influences spatial analysis and development models until today; (ii) human migration perceptions; (iii) a life-cycle model for mining settlements adapted from Luca’s mineral life-cycle model for resource towns (1971); (iv) the theoretical framework of Local Economic Development (LED); and (v) aspects of mining economics. The mixed-method approach to investigations facilitated the collation of primary data involving semi-structured questionnaires and face-to-face interviews. The data set formed the foundation for an in-depth analysis of the case study settlements’ scenarios. Linked to an indicator-supported viability model, the data analysis revealed distinct capacities of each settlement to achieve their people-centred urban sustainable development. Rosh Pinah, seemingly calm, well organized and well-managed, exposed a strong dependency on mining development that may harbour the potential for future decay and stagnation. This imponderability resulted from misapprehended local economic diversification efforts which could not unleash desired effects. At present, Rosh Pinah is to be rated ‘unviable’. The settlement might face the fate of Klein Aub, which prospered during its mining era, then declined, became depleted and has stagnated ever since the closure of the mine. Without external stimulus Klein Aub's prospects are bleak. Tsumeb, in contrast, exhibited great potential for socio-economic viability. Its dependency on mining has been resolved and the town continually transforms its urban structures and functions with the assistance of private-public engagement in joint local to regional LED-oriented long-term planning. In conclusion, lessons learnt from the three case studies point towards possible solutions which could pave the way towards sustainable growth and development of mining settlements in Namibia. Weaknesses which apparently are inherent in the country’s mining settlements and were observed during field study, should serve as a basis for future research and human capacity building, in order to establish a sustainable discourse among all key role players in planning the politico-economic, socio-cultural, and natural environment for the future generation.