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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

A COMPARATIVE STUDY OF LANDSLIDES AND GEOHAZARD MITIGATION IN NORTHERN AND CENTRAL MALAWI

Msilimba, Golden Gadinala Ashan Chizimba 04 September 2008 (has links)
In 2003, a number of landslides occurred in the Ntchenachena and the Chiweta Areas of the Rumphi District in Northern Malawi, and in the Livilivi/Mvai Catchments of Ntcheu District in Central Malawi. The landslide events caused significant damage to crops, farmland, livestock and infrastructure. Worse still, they caused the death of four people. The high density of landslides occurrences suggested instability of the slopes of these areas. In light of these landslides, this study set out to assess the slope stability status of the areas. The study addressed landslide mapping and classification of observed events; assessment of the causes and contributing factors; assessment of the socio-economic and environmental impacts of the events; exploration of traditional knowledge, beliefs and peoples perceptions surrounding landslides; determination of the coping strategies; and development of mitigations to landslides as geo-hazards. This study involved a landslide inventory of all observed This study involved a landslide inventory of all observed events. The physical characteristics of the terrain influencing slope instability were measured. The characteristics recorded included slope length, angles, aspect and altitude, and channel dimensions. Landslides were classified based on the type of movement, degree of stabilisation, and age, and materials involved in the movement. Soil samples were collected, using core and clod sampling methods and were tested for plastic limit, liquid limit, plasticity index, bulk density, hydraulic conductivity, aggregate stability, and particle sizes. Structural rock weaknesses were also measured. Vegetation data was collected, using the quadrant method and was analysed for average diameters at stump and breast height, canopy cover, and height. Questionnaires/surveys were used to assess local knowledge and perceptions towards landslides. A SPSS statistical package was used to analyse both social and physical data. It was found that 131 landslides had occurred of which 98 were in the Rumphi District, Northern Malawi and 33 occurred in the Ntcheu District, Central Malawi. The variations were observed to be due to the degree of disturbance of the physical environment. The Ntchenachena Area, with the highest density (88), was under cultivation and the afro-montane vegetation had been completely destroyed. The deepest channels were observed in the Ntchenachena Area, partly because of the deep chemical weathering of the basement. In contrast, the rest of the areas had thin soils. Slope aspect and type were found to be of little significance in the occurrence and spatial distribution of the events. The analysis of data suggested that the events were caused by liquefaction of sand and silt fractions due to high and prolonged precipitation. The evidence from the Chiweta and the Mvai Areas suggests that high cleft water pressure between rock and soil masses might have caused some failures. However, destruction of vegetation, cultivation on marginal lands, high slope angle, weathering of the basement, and slope cutting contributed to the instability. The study also noted that the Ntchenachena, the Mvai and the Livilivi Areas largely require soft solutions to the landslide problem. These include afforestation, proper siting of houses, and restricting settlement activities in danger-prone areas. Income generating activities to reduce poverty, community participation in natural resources management and public awareness and outreach programmes are highly recommended. The Chiweta Area requires urgent major engineering works such as construction of embankments, cable nets, wire meshes, improving drainage and plugging. Stabilisation and rehabilitation of river banks is also recommended to minimize bank collapse and flooding. Integration of traditional knowledge into the existing scientific body knowledge is critical to a better understanding of the mechanisms that generate landslides Further work needs to be carried out in areas of willingness to relocate to safer ground; change in production system; geological analysis of the Chiweta beds; hydro-geological assessment of the areas; development of landslides predictive models for Malawi; and the development of a landslide early warning system.
332

THE SOCIAL IMPACTS OF A LARGE DEVELOPMENT PROJECT: THE LESOTHO HIGHLANDS WATER PROJECT

Matli, Moeketsi Boniface 26 September 2006 (has links)
Projects are regarded as vehicles for development; developments are meant to enhance the quality of human life. Various types of development projects are carried out depending on the prevailing problems or opportunities, needs, objectives, target communities or areas, and the availability of resources and funds. Projects should have relevant activities particularly in the developing world in order that they can positively contribute towards developing mankind. Further, it is possible that some large water development projects like the Lesotho Highlands Water Project could easily be ill-considered developments resulting in extremely high costs and tremendous damage to the environment and human beings. Therefore, projects should ensure that the environmental impacts are properly mitigated, and that the distribution of benefits is fair while assuring that the underprivileged benefit well. A successful water development project must deliver to those immediately affected and to those it is meant to develop. The 1986 Water Treaty between the governments of Lesotho and South Africa guarantees better livelihoods for affected communities. Fixed royalties from the water sale, the variable royalties from taxes on some project activities and earnings from other activities such as increased tourism are expected to generate revenue income to raise the countryâs economy. Simultaneously, hydroelectric power is to make the country self-sufficient in energy. However, LHWP has spawned differing opinions on whether or not it has been a successful project this far. This is because its social impacts are mixed with benefits and detriments affecting many people and societies within Lesotho particularly in the project affected areas. The study has been conducted by holding discussions with sampled communities in dam-affected areas as well as in unaffected areas for broader national perspective. This has also afforded the opportunity to determine what Basotho locals think of LHWP. The mayhem of assets compensation, resettlement of displaced communities and the rural development programs in which LHWP finds itself in are the major determinants. Of prime importance is the compliance with the water Treaty signed by the Lesotho and the South African governments to better the well-being of affected communities. Comparative case studies show similarities of these socio-environmental impacts. The study focuses specifically on the rural dam development of Ha Katse and Ha Mohale in a developing country where poverty, lack of services and underdevelopment are dominant. It establishes how the negative and positive impacts affect people of the areas under study after nearly twenty years of the projectâs existence. Further, it aims to ascertain if social benefits engendered by LHWP vis a vis the cost of asset and resource losses borne by the Basotho justify the project, and whether the envisaged objectives have been met. Therefore, the study endeavours to determine the social impacts of LHWP as experienced and told by those affected by the dams and those that it is meant to develop. It also takes cognisance of the views of the water project authority, the Lesotho Highlands Development Authority, in this respect. Furthermore, through some recommendations, it sets out to encourage ever more that the project should be successful in that the benefits of the dams should encapsulate balanced economic, environmental and social sustainability.
333

A SPATIAL MULTI-RISK HAZARD ASSESSMENT AND VULNERABILITY STUDY OF MADIBENG [NORTHWEST PROVINCE]

Stols, Martin 04 October 2006 (has links)
A new act on Disaster Management has been introduced in South Africa that will shift the focus of Disaster Management to a pro-active approach. The new Disaster Management Act, Act number 57 of 2002, states that all Municipalities should provide for: âAn integrated and co-ordinated disaster management policy that focuses on preventing or reducing the risk of disasters, mitigating the severity of disasters, emergency preparedness, rapid and effective response to disasters and post disaster recoveryâ. Because of this it is important to identify areas that are at risk of any disaster and to introduce mitigating measures to ensure that any foreseeable impacts on the community are limited as much as possible. It is thus important that a disaster risk assessment must be performed for every Municipality that can be used in the planning process. A great deal of information needs to be gathered and analysed in the risk and vulnerability assessment process. Geographic Information Systems (GIS) provides the ideal platform from which to analyse large quantities of environmental, demographic, cadastral and infrastructural data and represent it spatially and in a format that is easily understandable to everyone. GIS has proven to be a very important tool in disaster management, from identifying hazards and vulnerable communities, to providing information during disaster events and the recovery process afterwards. It is also a very effective method of gathering and storing data from different fields and applications to be used for planning mitigating measures, setting up standard operating procedures for disaster events and coordination and planning in the event of a disaster. The purpose of this study was to gather all available information on identified hazards in the Madibeng Municipality and to use this information to perform a risk and vulnerability assessment of the Madibeng Local Municipality with the aid of GIS. The information provided in this study was intended to assist in building a disaster resistant community by sharing geographic knowledge about local hazards. This study provides information to the Municipality of Madibeng on hazards and people at risk and vulnerable to different hazards. Recommendations were then made to the Madibeng Municipality on the application of GIS in hazard and vulnerability assessments, that should provide the Municipality with a cost effective and scientific method of addressing Disaster Management related functions.
334

URBAN WATER PROVISION IN MASERU (LESOTHO): A GEOGRAPHICAL ANALYSIS.

Molapo, Lifuo 10 November 2005 (has links)
Water is the most important of all basic needs, and is fundamental to all vital processes of value to mankind. However, statistics indicate that of all the water available on earth, only a limited fraction is available for human consumption. With the growing world population, there is increasing demand for water worldwide. The situation is even more complicated in cities of the developing world that are characterised by rapid population growth while the economic status is low. This often results in the demand for water growing faster than the ability to supply. Urban population expansion in the developing world therefore further complicates the challenge of water provision. This is a very critical issue because failure to meet the water demands of cities can put peopleâs lives at risk. The main challenge therefore is to develop appropriate policies that guide water provision. This is also the situation in Lesotho. Like other developing countries, Lesothoâs population has been growing at an alarming rate. Most of the growth has been happening in the capital city Maseru, which absorbs a high share of the countryâs urban population. However, the fast rate of urbanisation in Lesotho, particularly in Maseru has not been coupled with the necessary expansion of water supply systems, thereby causing pressure of the existing system. WASA the body that is charged with the responsibility of urban water supply in Lesotho has since its formulation generally failed to meet its obligation. This is as a result of ineffective policies that were put in place to guide the authority. About half of the population within WASAâs area of designation are still unserved. Several policy related issues have resulted in this. Firstly, the subsidisation of water by disallowing price increases. Secondly, the supply of free water through public standpipes, and thirdly the false assumption that the poor cannot afford to pay even the minimum charge for water. These issues have not only resulted in financial instability to WASA thus hindering service expansion, but have also resulted in denial of service to the poor while the rich enjoyed low cost service. Empirical examination of the situation on water provision in Maseru has further confirmed the issues discussed above. From a policy perspective it is therefore imperative tha t water supply services are expanded and improved to be financially viable.
335

AN EVALUATION OF THE SPATIAL VARIABILITY OF SEDIMENT SOURCES ALONG THE BANKS OF THE MODDER RIVER, FREE STATE PROVINCE, SOUTH AFRICA.

Tsokeli, Raboroko David 10 November 2005 (has links)
The study focuses on the characteristics of the Modder River in the Free State. The Modder River plays an important role in supplying water for domestic, agricultural and industrial uses in the Bloemfontein, Botshabelo and Thaba Nchu areas. According to present (2001) estimates by the Centre of Environmental Management of the University of the Free State, the Modder River is exploited to its full capacity owing to the construction of dams. As the name of river suggests, the Modder River is said to have high sediment loads. In Afrikaans, modder means mud. The drainage pattern of the Modder River reveals well-developed dendritic drainage on the eastern part of the catchment and an endoreic drainage pattern on the western part. This study aims to evaluate the spatial variability of sediment sources along the main course of the Modder River as well as assess the possible role of fluvial geomorphology in river management. The study is based on the hypothesis that the high sediment load in the Modder River main course is caused more by riverbank processes than by the surface of the basin. Helicopter and fieldwork surveys were carried out in order to obtain the required materials (variables). The spatial variability of bank-forming material, vegetation cover, type and channel form were investigated in order to realise the aim of this study. The channel form of the Modder River indicates a decrease in sediment loads since the channel form shows some shrinkage immediately below the Krugersdrift Dam. The Modder River transports less and less sediments downstream as a result of a high number of constructed dams. Dams are barriers that create discontinuities in the channel system. Observations of the characteristics of the banks of the Modder River reveal that these banks are resistant to erosion owing to the luxuriant vegetation growth and low stream power because of the channel gradient. A question arises as to whether the Modder River really has such high sediment loads as its name suggests. Given the current state of the Modder River, high sediments are highly localised at certain sections of the stream. The transfer of sediments from one part of the river to another depends on the availability of sediment sources in space and time.
336

A COMPARATIVE STUDY OF THE QUALITY AND OUTCOMES OF ENVIRONMENTAL IMPACT ASSESSMENT REPORTS FROM THE FREE STATE AND NORTHERN CAPE PROVINCES

Freemantle, Sophia Johanna 15 February 2010 (has links)
An Environmental Impact Assessment (EIA) determines the economic, social and environmental impacts of proposed developments. Environmental Impact Assessment reports are complied by independent consultants in order to provide the authorities with information on the anticipated impacts on the environment caused by a proposed activity or development. The authorities therefore base their decision largely on the EIA document and trust that the information about forecasted impacts are to a large extent accurate. Authorities also trust that the mitigation measures proposed in the Record of Decisions (RODs) and Environmental Management Plans (EMP`s), in order to minimize impacts on the environment, are implemented during the construction and operational phases of a project. Post-authorization activities such as monitoring and auditing are the only feedback mechanisms to provide authorities with information on the extent to which predicted impacts materialised and whether mitigation measures were implemented. Post authorization activities, especially auditing is to a large extend neglected because it was not mandatory in South Africa under the Environmental Impact Assessment regulations promulgated on September 1997 in terms of Environment Conservation Act 107 of 1989. Therefore the accuracy of predicted impacts and the implementation rate of mitigation measures in South Africa are to a large extent unknown. The aim of the study is to assess the accuracy of predicted impacts and the implementation rate of mitigation measures of activities that received authorization from the Departments of Environmental Affairs in the Free State and Northern Cape provinces, in South Africa. The objective of the study is to determine if any improvements are necessary to EIA reports, to establish whether authorities base their decisions on correct information. The adequacy or success of proposed mitigation measures will also aid decision makers in suggesting preventative measures. The research problem posed in this study was two-fold. First the question relating to the accuracy of predicted impacts and implementation of mitigation measures in the Free State and Northern Cape had to be answered. This was done through a method called impact-backwards auditing. Secondly the question whether the two provinces had similar outcomes in terms of predicted impact accuracy and implementation of mitigation measures, had to be assessed. The comparison between the two provinces was conducted through a series of Pearson chi-square tests on contingency tables to assess if statistically significant differences occurred in the outcome of predicted impacts and mitigation measures between the Free State and Northern Cape provinces. This study concluded that no statistically significant differences occurred between the two provinces in relation to the outcome of predicted impacts and mitigation measures. Predicted impacts were to a large extent accurately predicted and the majority of mitigation measures were to a large extent implemented successfully to prevent or minimize an impact.
337

ASPEKTE RAKENDE DIE RUIMTELIKE EKOLOGIE VAN DIE ROOIJAKKALS (CANIS MESOMELAS) AS PROBLEEMDIER IN DIE SUID-VRYSTAAT

Deacon, Francois 19 October 2011 (has links)
According to the Red Meat Producersâ Organisation, damage-causing predators annually catch small stock to a value of approximately R1,1 billion in South Africa. On most of the small stock farms in the Southern Free State, black-backed jackals, Canis mesomelas, are shot on sight and actively hunted to provide a safe environment for domesticated animals. The veld and habitats previously occupied by natural prey for these carnivores are now used for commercial farming practices. Carnivores are conserved in established formal protection and conservation areas within the ecosystem to lessen their contact with small stock. In South Africa the black-backed jackal successfully adapts to this farming environment with visible adaptation patterns. These behavioural patterns are influenced by the circumstances of the animal and variables within its environment. In the study area these fixed patterns of the black-backed jackal presumably annually repeat itself. This study researched these behavioural patterns of the jackal. For the first time, geographic information systems (GIS) are used in the research of the black-backed jackal. Since 2006, black-backed jackal regional data (of all jackals killed during hunting operations) was collected in a high depredation area in the Southern Free State. Data points collected from 1927 to 2009 were accordingly entered on electronic charts in ArcView. The total number of data points were obtained from 433 black-backed jackals killed, with the localities of 344 charted. The data is grouped into four sets: the first set, collected over 26 years, 1927 to 1953, consisted of 15 black-backed jackals; the second set, collected over 5 years, 1993 to 1997, consisted of 124 black-backed jackals; the third set, collected from 1999 to 2008, 10 years, consisted of 210 black-backed jackals; and the fourth set, from 2006 to 2009, four years, had a total of 84 black-backed jackals. Therefore, the number of black-backed jackals killed significantly increased, from 15 killed the first 26 years, to 418 over the last 16 years, within the same specific area. The increase in numbers of black-backed jackals removed from the area is used as indication of the increase in damage over the years in the study area. The average mass of 68 males, killed between 1993 and 1997, was 7.15kg and 63 females, 6.72kg. According to the 35 farmers in this specific area of the Southern Free State, the jackal problem is at present more under control than 30 years ago, which also applies to some other parts of the Southern Free State and South Africa. The reason for this can be ascribed to a better understanding of the animals and planning of hunting expeditions. In the late 1980âs, the average loss per farmer was ± 200 sheep per annum. At present, about 40 sheep on average are lost per farmer. The aim of this study is to further alleviate the damage-causing problem in the study area by making accurate predictions and planning to decrease losses. In the study area, peak losses are noted annually from August to October and March to May. The black-backed jackals mainly follow certain fixed movement patterns in the study area and breeding pairs seemingly react to the same stimuli from their direct environment. The same dens are repeatedly used and there is a clear relationship between the location of the dens and human activities. When a breeding pair is removed from an area, a new breeding pair will soon establish there. The processing of historic data leads to predictions on where the black-backed jackals will establish, where they will breed and where they will probably cause damage. It also predicts where they can probably be caught. This study shows a strong correlation between the physical nature of the environment and the black-backed jackals.
338

SECOND HOMES AND LOCAL ECONOMIC IMPACTS IN THE SOUTH AFRICAN POST-PRODUCTIVIST COUNTRYSIDE

Hoogendoorn, Gijsbertus 19 October 2011 (has links)
Issues concerning post-productivism have not seen any direct systematic research attention in South Africa. Nevertheless, it has recently been proposed that post-productivism, although difficult to discern in its early stages, has gathered sufficient momentum to warrant scholarly attention in the local context. This study develops this contention by focusing on the role of second homes tourism as a contributor to developing a South African post-productivist countryside using four study areas, namely, Rhodes, Greyton, Dullstroom and Clarens. It is argued that the initial development of productivist countrysides was linked to the apartheid regimeâs concerns over white land ownership, black labour distribution and food security. It is then suggested that although the productivist countryside was under strain towards the final years of apartheid, the dismantling of apartheid agricultural policy and financial support for white farmers led them to seek out other economic opportunities. Movement towards consumptive leisure practices such as tourism and leisure functions has led to a diversification of farming practices resulting in a countryside in which agricultural production has decreased in importance. It is then argued that the stage was set for second homes to emerge as a new phenomenon in the countryside which further enhances the trend towards post-productivism. The project then provides an analysis of the various economic impacts of second homes in four study sites mentioned.
339

A CRITICAL REVIEW OF THE QUALITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORTS IN LESOTHO

Talime, L A 19 October 2011 (has links)
Environmental impact assessment (EIA) is one of the tools used by relevant authorities all over the world in an attempt to ensure that the principles of sustainable development are achieved. Since the Environment Act (EA) No. 15 of 2001 was passed in the parliament many EIAs have been conducted in Lesotho. This Act has been replaced with the EA No. 10 of 2008. Though it was not until June 2009 that the environmental law was promulgated, government institutions and environmental practitioners have been operating within the provisions of this Act. The preparation of high quality EIA reports is one component of an effective translation of EIA policy into practice. The Lee and Colley review package (Lee et al 1999) was used to assess the quality of 15 EIA reports submitted to the National Environment Secretariat which is now referred to as the Department of Environment (DoE). The reports comprised of the project briefs (PBs) and the environmental impact statements (EISs). Interviews with the EIA consultants, stakeholders and concerned government officials have also been conducted to underpin the root cause of poor quality of EIA reports. The analysis reveals that several key areas of EIA do not receive sufficient attention. The inadequacies are particularly in areas relating description of the development, identification, evaluation and mitigation of key impacts, consideration of alternatives, and consultation and participation of the public. The government institutions also show less interest in environmental matters and as a result matters relating to environment are given less priority. This leaves the effectiveness of the EIA process to be highly questionable. The study offers suggestions that would improve the EIA process in the country.
340

THE INFLUENCE OF CLIMATE VARIABILITY ON FLOOD RISK IN THE //KHARA HAIS MUNICIPALITY (UPINGTON AREA) : A GIS â BASED APPROACH

Jacobs, Kirsten 22 November 2010 (has links)
The climate of the continents and the world is controlled by complex maritime and terrestrial interactions that produce a variety of climates across a range of regions and continents. Climate influences agriculture, environment, water and even the economy of countries all over the world. The climate of the world varies from one decade to another and a changing climate is natural and expected. However, there is a well-founded concern that the unprecedented human industrial and development activities of the past two centuries have caused changes over and above natural variation. Climate change is the natural cycle through which the earth and its atmosphere accommodate the change in the amount of energy received from the sun. A hazard is a physical situation with a potential for human injury, damage to property, damage to the environment or some combination of these. It is important to distinguish between the terms disaster and hazard. A disaster is seen as a serious disruption of the functioning of a community or society, causing widespread human, material or economic losses which exceed the ability of the affected community to cope, using its own resources. Disasters can be either natural, for instance a flood, or human induced, such as a nuclear accident. Disasters may furthermore be classified as slow-onset disasters, such as a drought, or sudden disasters, such as an earthquake . The word risk is one of the most notable examples of words with multiple and disparate meanings that may not be commonly acknowledged. Risk may have a technical meaning, referring to a chance or probability, such as risk from exposure, a consequence or impact, an example being the risk from smoking, or a perilous situation like a nuclear power plant that creates a risk. This study examines the influence of climate variability on flood risk in the //Khara Hais Municipality in the Northern Cape. The area that was investigated included the entire Orange River and Vaal River catchment areas where monthly rainfall data, as well as runoff data were used to produce a flood model for predicting a flood event within a two-month period, giving enough warning time to farmers and the inhabitants of the areas that may be influenced by this flood event. Maps were produced to show the high and low rainfall amounts in the these two catchment areas where randomly selected years and months were taken, as well as showing the one-month and two-month periods before these selected dates. Examples of the highest rainfall recorded, which was in 1988, the medium amount in 1977, and the lowest amount in 1997 were selected. Furthermore, five other such examples were taken to examine the rainfall and climate variation between the years and months ranging from 1950 to 1999.

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