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Item Rooting strategies of savanna shrubs in the Kalahari basin: Implications for the coexistence of woody and herbaceous plants and shrub encroachment in the African savannas(University of Namibia, 2020) Nakanyala, JesayaThe savanna biomes are characterised by a coexistence of two antagonist – woody plants and herbaceous plants in defiance of competition theories. Scientific efforts to understand this unique coexistence are still largely inconclusive; various theories have been proposed, but no unanimous theoretical framework exists to date. Among these theories, the root niche-partitioning model offers the most popular, yet the most controversially debated viewpoint. It argues that this coexistence is a result of vertical root niche-partitioning, a natural mechanism by which woody plants develop deeper root systems to avoid competition with herbaceous plants. Despite its prominence and subsequent integration into models of species coexistence and arid eco-hydrology, several shortcomings of this model are evident. For example, it overlooks the critical issue of root plasticity. This study was thus designed to investigate the root systems of various savanna shrubs across a rainfall gradient in the Kalahari to test the aforementioned model. The overall aim was to investigate, compare, and contrast the root system architecture (RSA) of encroaching shrubs and those of non-encroaching shrubs within the proximate environmental setting. Using a direct excavation method, 183 shrubs were sampled, had their roots exposed and were subjected to morphometric measurements. Shrub encroachers were randomly selected and four non-encroaching shrubs surrounding each of the sampled encroacher plant were systematically chosen, using the nearest-neighbour approach. Results indicated that shrubs in the Kalahari develop diverse root system architecture which exhibits significant inter- and intra-species plasticity. In particular, three bush encroaching shrubs, Terminalia sericea, Senegalia mellifera, and Dichrostachys cinerea, tend to develop root systems essentially composed significantly (p < .001) of lateral roots deployed within shallow soil sub-surfaces; and partly without taproots, more especially in the drier part of the Kalahari. Overall, the architecture of the savanna shrubs’ root system can be classified into three major architecture groups: i) a fibrous or lateral root system, ii) a dual root system, and iii) a taproot system. These architecture groups are not necessarily unique to any species or environment, which suggests that plants develop their root systems plastically in response to prevailing environmental conditions. These findings are not consistent with the premise that the savanna shrubs are largely deep-rooted. This oversight has major implications for our current understanding of the savanna biomes. Whereas deeper-rooted shrubs may allow for root niche-partitioning with grasses, shallow-rooted shrubs are potentially in direct competition with grasses, suggesting that shrub encroachment is a probable manifestation of this competition. These findings may also explain why the phenomenon of shrub encroachment is largely attributed to shallow-rooted shrubs such as T. sericea.Item Rooting strategies of savanna shrubs in the Kalahari basin: Implications for the coexistence of woody and herbaceous plants and shrub encroachment(University of Namibia, 2020) Nakanyala, JesayaThe savanna biomes are characterised by a coexistence of two antagonist – woody plants and herbaceous plants in defiance of competition theories. Scientific efforts to understand this unique coexistence are still largely inconclusive; various theories have been proposed, but no unanimous theoretical framework exists to date. Among these theories, the root niche-partitioning model offers the most popular, yet the most controversially debated viewpoint. It argues that this coexistence is a result of vertical root niche-partitioning, a natural mechanism by which woody plants develop deeper root systems to avoid competition with herbaceous plants. Despite its prominence and subsequent integration into models of species coexistence and arid eco-hydrology, several shortcomings of this model are evident. For example, it overlooks the critical issue of root plasticity. This study was thus designed to investigate the root systems of various savanna shrubs across a rainfall gradient in the Kalahari to test the aforementioned model. The overall aim was to investigate, compare, and contrast the root system architecture (RSA) of encroaching shrubs and those of non-encroaching shrubs within the proximate environmental setting. Using a direct excavation method, 183 shrubs were sampled, had their roots exposed and were subjected to morphometric measurements. Shrub encroachers were randomly selected and four non-encroaching shrubs surrounding each of the sampled encroacher plant were systematically chosen, using the nearest-neighbour approach. Results indicated that shrubs in the Kalahari develop diverse root system architecture which exhibits significant inter- and intra-species plasticity. In particular, three bush encroaching shrubs, Terminalia sericea, Senegalia mellifera, and Dichrostachys cinerea, tend to develop root systems essentially composed significantly (p < .001) of lateral roots deployed within shallow soil sub-surfaces; and partly without taproots, more especially in the drier part of the Kalahari. Overall, the architecture of the savanna shrubs’ root system can be classified into three major architecture groups: i) a fibrous or lateral root system, ii) a dual root system, and iii) a taproot system. These architecture groups are not necessarily unique to any species or environment, which suggests that plants develop their root systems plastically in response to prevailing environmental conditions. These findings are not consistent with the premise that the savanna shrubs are largely deep-rooted. This oversight has major implications for our current understanding of the savanna biomes. Whereas deeper-rooted shrubs may allow for root niche-partitioning with grasses, shallow-rooted shrubs are potentially in direct competition with grasses, suggesting that shrub encroachment is a probable manifestation of this competition. These findings may also explain why the phenomenon of shrub encroachment is largely attributed to shallow-rooted shrubs such as T. sericea.Item Recycling solid waste: A study on an emerging raw material industry in Namibia(University of Namibia, 2019) Mutede, Tandiwe P.The aim of the study was to assess solid waste recycling as an emerging source of raw material in Namibia. Recycling solid waste has become part of society. In striving to meet the high demand for raw materials and finding solutions to waste management challenges, countries worldwide are turning to recycling of solid waste. In developing countries, recycling is an emerging industry. While there have been numerous studies on recycling processes, very few studies have focused on recycling as an emerging source of raw material industry and little or no research has been conducted on recycling as an emerging source of raw material in Namibia. This study aimed to investigate this emerging industry in Namibia. This study was a descriptive case study, qualitative in nature employing interviews, document search and observation to collect data to achieve various objectives namely: to investigate the motives and extent of involvement of companies in solid waste recycling in Namibia, examine legislation and policies, guiding waste recovery and recycling in Namibia, establish emerging waste recycling growth trends, assess industry value addition processes and associated benefit chains and examine local and regional operational network linkages in the industry. The study investigated all these issues applying existing waste management concepts and attempted to establish progress of recycling as an emerging raw material industry in Namibia. The units of analysis comprised fifteen recycling companies in Namibia. Purposive and accidental sampling methods were used to select the companies. The data was analysed manually using content analysis and presented in descriptive narrative with some illustrative tables and figures. The study showed that recycling industry in Namibia is still in its infancy with most of the activities still concentrated in the recovery, collection and semi processing stage of the recycling loop. Little production of raw materials and products is done locally. Only plastic material formed a complete recycling loop in Namibia. Final processing and subsequent production of new goods for the rest of the materials recycled; paper, glass bottles, cans, scrap metal and electronic waste is done outside the country a situation which may disadvantage the country in terms of industrial and economic growth. Economic and environmental factors were the main forces driving the industry. There was a shift from informal to formal sector dominance in the industry. A host of challenges still hinder the potential success of the industry. There is need to improve on the legal and regulatory environment which controls and governs the industry. Despite these challenges, the industry is a welcome development in the country, as it has become a source of employment as well as a waste reduction measure. Networking within the industry both local and regional facilitates its survival. The study recommends for an integrated recycling model for Namibia which could assist solid waste management. Such a model could promote a culture of recycling, review of legal and regulatory framework, building technical capacity through the establishment of a Recycling Fund and development of program of action including an establishment of a national database of recyclable waste.Item The development and evolution of Etosha Pan, Namibia(University of Wurzburg, 2005) Hipondoka, MartinThis 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.Item Development of mining settlements in Namibia: An investigation into prospects for Rosh Pinah, Klein Aub and Tsumeb(University of Namibia, 2015) Stankevica, VitaThe 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.Item Vegetation survey of Namibia: conceptualisation and implementation of a nation-wide vegetation survey serving practical land management needs(2014) Strohbach, Ben J.The global human population is dependant on a variety of plant-based ecosystem services for its well-being, even for its very existence. The well-being, in fact, the very existence of man is dependant upon plant-based ecosystem services. Typical services derived from ecosystems encompass food production {crop growing or provision of pastures for livestock and game), the provisioning of raw materials, including a profusion of materials and processes, such as building materials, fuel, water, shelter, erosion control and sediment retention, soil formation and nutrient cycling, waste treatment, gas and climate regulation, pollination, disturbance regulation and biological control {of, e.g., pests and diseases), genetic resources, and the provision of opportunities for recreational and cultural activities (Butler and Oluoch-Kosura, 2006; Corvalan et al., 2005; Costanza et al., 1997; Daily, 1997). In order to provide these services, ecosystems need to function well and biodiversity is a key feature of well-functioning ecosystems. Numerous studies show that species diversity is closely correlated with net primary production: adverse {climatic) variations are compensated for by a highly diverse composition with different traits and functional niches {Costanza et al ., 2007; Dobson et al., 2006; Lamont, 1995; Lareau, 2000; Peterson et al., 1998; Tilman, 1996; Tilman et al., 1997, 1996).Item Exile history(2009) Williams, Christian A.; Cohen, David; Lemon, Alaina M.; Ashforth, Adam P.; Hayes, Patricia; Ticktin, Miriam I.From 1960 to 1989 thousands of Namibians fled South African apartheid rule and traveled into “exile,” a space located outside their country of origin. Most exiles lived in camps administered by the Namibian liberation movement SWAPO in Tanzania, Zambia and Angola. Through the distribution of resources, management of interactions and control of information in these camps, a national hierarchy formed which empowered internationally recognized SWAPO leaders and endangered other camp inhabitants, especially those who were already marked as culturally different. Histories of exile have, in turn, become a medium through which Namibians reproduce, contest and negotiate their position in the hierarchy formed in the camps. It is this relationship between the exile past and present that I call “exile history.” These observations are significant not only for Namibia, but also for other nations and the scholars who study and influence social relations in them. Like SWAPO, liberation movements representing South Africa, Zimbabwe, Angola and Mozambique first governed their citizens in exile camps before becoming the ruling parties of independent countries. Moreover, “exile” and “the camp” highlight paradoxical qualities of national history generally, with its tendency to form outside national borders, insistence on a unity that produces and masks divisions, and capacity to “silence” even as it evokes competing narratives. Such qualities present challenges to the researcher which are best addressed through ethnographic methods. For while national histories tend to be dominated by hierarchies formed in exile, camps and similar spaces, ethnography enables the researcher to cross sites of historical production and elicit new ones. Histories accessed in this way may, in turn, be used to illuminate nationalism's contradictions and create space for other forms of community.Item Community-based conservation and protected areas in Namibia(2008) Hoole, ArthurItem Une histoire des grands hommes(1999) Gillouin, CarineItem Tephrostratigraphy, petrography, geochemistry, age and fossil record of the Ganigobis shale member and associated glaciomarine deposits of the Dywka group, late Carboniferous, southern Africa(2000) Bangert, Berthold;Abstract provided by author: