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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.
1

How green is our future? Thor Chemicals: a case study in South African environmental policy

Flint, Adrian January 1998 (has links)
This study focuses on South African Environmefltal policy; in particular its policies regarding hazardous waste. These policies are addressed within the framework of a case study which serves as basis to critically evaluate government environmental policies both past and present. The thesis examines South African environmental policy against the backdrop of competing schools of thought regarding the relationship between growth and development on the one hand and long term environmental security on the other. Development strategies such as Sustainable Development and the government's Growth, Employment and Redistribution as well as philosophies such as Deep Ecology will be discussed. The thesis argues that Non-Governmental Organisations are the holders of a real environmental ethic and thus their role in preventing environmental degradation is of critical importance. Furthermore, it is imperative that this ethic be disseminated across society if South Africa is to successfully pursue sound environmental policies. This argument is pursued by way of a case study, Thor Chemicals: a company responsible for the running of the largest mercury recovery facility in the world. This plant, which operated in Cato Ridge, KwaZulu-Natal, has been the source of much controversy since it was found that many of its employees and ex-employees were suffering from severe mercury poisoning resulting in two fatalities. The company was also involved in the importation of hazardous wastes as well as the pollution of the surrounding environment. Thor is currently the subject of inquiry by the government-appointed Davis Commission. It is pointed out that ill the past South Africa held no real environmental ethic and environmental degradation ensued as a result. The presented thesis argues that, despite assurances to the contrary, the present government is also without a true environmental ethic that will be effective in preventing future degradation.
2

A comparative study of the Rooikraal and Marie-Louise landfill sites indicating differences in management strategies, and the consequences thereof on operational and management issues.

Geldenhuys, Lukas Marthinus Marais 18 June 2013 (has links)
M.A.(Geography) / The prevention of environmental deterioration and the concept of sustainable development has become a major concern worldwide. However, increasingly affluent lifestyles along with continual commercial and industrial growth have led to the rapid increase in waste production (Renoua et al., 2008). The most common method of dealing with this production of waste is the disposal thereof by landfill, although this technique is widely viewed as unsustainable. Landfilling is critical to integrated waste management in South Africa due to its simplicity and cost effectiveness (Allen, 2001). Thus, there is a great need for environmentally acceptable landfill management practices. This research is primarily concerned with landfill management strategies and their effect on operational and management issues. A comparative analysis of the Marie Louise and Rooikraal landfill sites was carried out to distinguish differences in landfill management strategies and their outcome on operational and management issues. A concept, indicator, variable approach was used as comparative framework, while external audit reports, landfill management plans, and interviews were used as data sources identifying indicators and variables for analysis. Findings revealed that the Rooikraal landfill has been performing at a high standard, while the Marie Louise landfill has been underperforming due to a number of management failures. Factors that could have contributed to this failure include: external factors and its strain on effective management, capacity of local governments to deliver services with regard to waste management, issues surrounding co-operative governance, legal enforcement and compliance, and lack of control and awareness over landfill operations. These issues are direct consequences of landfill management and operation through municipal entities, making landfill management through municipal entities a key area of concern for effective landfill operations.
3

Factors affecting the success of reseeding rehabilitation in the semi-arid Karoo, South Africa

Matthee, Willem January 2015 (has links)
Due to overgrazing, mining and other anthropogenic disturbances, large sections of the Karoo region have been degraded, resulting in areas with low vegetation cover, where erosion rates are high and vegetation is dominated by unpalatable species. These areas have low and unpredictable rainfall, with slow to non-existent autogenic recovery, and this often forces landowners to implement reseeding rehabilitation in an attempt to increase both overall vegetation cover and the relative abundance of palatable plants. Landowners use soil preparation treatments, which include creating micro-catchments, ripping, mulching and brush packing, to supplement land rehabilitation. This study investigated the significance of initial rainfall, mean monthly rainfall, soil preparation techniques, slope, existing vegetation cover, litter, mulch and stone cover in determining the success of reseeding rehabilitation. Rainfall had the most significant influence, where long-lived shrubs established best under low initial rainfall and high mean monthly rainfall, and grasses established best after receiving high initial rainfall. Micro-catchments proved the most successful soil preparation technique for the establishment of long-lived shrubs, while ripping and mulching impacted negatively on grass establishment. A combination of mulch and micro-catchments aided Osteospermum sinuatum establishment in soils where soil shrinkage cracks occurred. Temperature influenced seed germination and drought tolerance of Lessertia annularis, Fingerhuthia africana and O. sinuatum, with higher germination success of O. sinuatum under temperatures simulating summer, and of F. africana under temperatures simulating winter. L. annularis germination had a faster growth rate and higher survival when germinated under autumn/spring temperatures. Landowners are advised to sow seeds of more than one species during rehabilitation, to include micro-catchments as soil preparation treatment, and to sow seeds during a time when rainfall is predicted to be high.
4

Land degradation in the Northern Province : physical manifestations and local perceptions

Dzivhani, Mashudu Almond 03 1900 (has links)
Thesis (MA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The study traces some of the causes and effects of land degradation in Mutale since it is an environmentally challenging issue associated with depletion of resources. The degradation conditions identified by the Provincial Department of Agriculture in the Northern Province support the aims of this study. Based on information obtained from the physical survey of the area and through questionnaires and interviews with the local people, it is evident that the environmental conditions of Mutale district have worsened due to the influence of land usage. From the survey made, the physical conditions are shown to be in a state of decline and to impact negatively on the soil and vegetation. The perceptions of the local community regarding physical change revealed that a variety of activities such as gathering fuel wood, fencing, stocking, and cultivating fields, influence each other and exacerbate the encroachment of degradation conditions. Stock worsens the conditions through uncontrolled grazing associated with lack of grazing camps, trampling, and overgrazing. Extension of fields, residential areas, and inescapable massive harvesting of bush for different purposes are seen as further causes of the worsening state of the environment. In the past attempts were made to curb the environmental decline, but such conservation measures were not fruitful enough as they changed from time to time and land users were alienated from land on which they depended. The present study recommends the implementation of LandCare, a programme that the Department of Agriculture has adopted in other parts of the country, as a possible solution to some of the environmental problems, and as a conservation measure. / AFRIKAANSE OPSOMMING: Die studie ondersoek sommige van die oorsake en gevolge van omgewingsdegradasie by Mutale, omdat dit 'n omgewings-uitdagende kwessie is wat met die uitputting van hulpbronne in verband staan. Die degradasietoestande wat deur die Provinsiale Landboudepartmente in die Noordelike Provinsie geïdentifiseer is, bied ondersteuning aan die doelstellings van hierdie studie. Vanuit die inligting wat deur middel van 'n empiriese ondersoek in die gebied en deur vraelyste en onderhoude met die plaaslike mense verkry is, is dit duidelik dat omgewingstoestande in die Mutale distrik vanweë die manier van grondgebruik verswak het. Vanuit die ondersoek wat gedoen is, word aangetoon dat fisiese toestande agteruitgaan en 'n negatiewe impak op die grond en plantegroei het. Waarneming deur die plaaslike gemeenskap met betrekking tot fisiese verandering dui aan dat 'n verskeidenheid aktiwiteite, soos die versameling van brandhout, bou van heinings, aanhou van vee en bewerking van landerye mekaar affekteer en die toename van die degradasietoestande veroorsaak. Vee vererger verder die toestande deur onbeheerde weiding wat verband hou met die gebrek aan weidingskampe. Die onafwendbare en grootskaalse afkap van die bos vir 'n verskeidenheid doeleindes word beskou as verdere oorsake van die toestand waarin die omweging verkeer. Pogings is in die verlede aangewend om die agteruitgang van die omgewing te keer, maar die bewaringsmaatreëls het nie genoeg vrug afgewerp nie, daar hulle van tyd tot tyd gewysig IS en die grondeienaars vervreemd geraak het van die grond waarvan hulle afhanklik was. Hierdie ondersoek beveel aan dat "LandCare", 'n program wat deur die Departement van Landbou vir ander dele van die land goedgekeur is, as ' n moontlike oplossing vir sommige van die omgewingsprobleme en as bewaringsmaatreël toegepas word.
5

Grossly overgrazed veld near Middeldrift

Skead, C J (Cuthbert John) 10 1900 (has links)
Caption "Grossly overgrazed Bantu veld near Middledrift, K.W. Town. Oct. 1962. Note remnants of a few trees..."
6

Monitoring carbon stocks in the sub-tropical thicket biome using remote sensing and GIS techniques : the case of the Great Fish River Nature Reserve and its environs, Eastern Cape province, South Africa

Nyamugama, Adolph January 2013 (has links)
The subtropical thicket biome in the Eastern Cape Province of South Africa has been heavily degraded and transformed due overutilization during the last century. The highly degraded and transformed areas exhibit a significant loss of above ground carbon stocks (AGC) and loss of SOC content. Information about land use /cover change and fragmentation dynamics is a prerequisite for measuring carbon stock changes. The main aim of this study is to assess the trends of land use/cover change, fragmentation dynamics, model the temporal changes of AGC stocks in the Great Fish River Nature Reserve and its environs from 1972 to 2010, quantify and map the spatial distribution of SOC concentrations in the partial subtropical thicket cover in the Great Fish River Nature Reserve and environs (communal rangelands). Multi-temporal analyses based on 1972 Landsat MSS, 1982 and 1992 Landsat TM, 2002 Landsat ETM and 2010 SPOT 5 High Resolution images were used for land use/cover change detection and fragmentation analysis. Object oriented post-classification comparison was applied for land use/cover change detection analysis. Fragmentation dynamics analysis was carried out by computing and analyzing landscape metrics in land use/cover classes. Landscape fragmentation analyses revealed that thicket vegetation has increasingly become fragmented, characterized by smaller less linked patches of intact thicket cover. Landscape metrics for intact thicket and degraded thicket classes reflected fragmentation, as illustrated by the increase in the Number of Patches (NP), Patch Density (PD), Landscape Shape Index (LSI), and a decrease in Mean Patch Size (MPS). The use of remote sensing techniques and landscape metrics was vital for the understanding of the dynamics of land use/cover change and fragmentation. Baseline land use/cover maps produced for 1972, 1982, 1992 2002 and 2010 and fragmentation analyses were then used for analyzing carbon stock changes in the study area. To model the temporal changes of AGC stocks in the Great Fish River Nature Reserve and its environs from 1972 to 2010, a method based on the integration of RS and GIS was employed for the estimation of AGC stocks in a time series. A non-linear regression model was developed using NDVI values generated from SPOT 5 HRG satellite imagery of 2010 as the independent variable and AGC stock estimates from field plots as the dependent variable. The regression model was used to estimate AGC stocks for the entire study area on the 2010 SPOT 5 HRG and also extrapolated to the 1972 Landsat MSS, 1982 and 1992 Landsat TM, and 2002 Landsat ETM. The AGC stocks for the period 1972 -1982, 1982-1992, 1992-200) and 2002-2010 were compared by means of change detection analysis. The comparison of AGC stocks was carried out at subtropical thicket class level. The results showed a decline of AGC stocks in all the classes from 1972 to 2010. Degraded and transformed thicket classes had the highest AGC stock losses. The decline of AGC stocks was attributed to thicket transformation and degradation which were caused by anthropogenic activities. To map and quantify SOC concentration in partial (fractional) thicket vegetation cover, the spectral reflectance of both thicket vegetation and bare-soils was measured in situ. Soil samples were collected from the sampling sites and transported to the laboratory for spectral reflectance and SOC measurements. Thicket vegetation and bare soil reflectance were measured using spectroscopy both in situ and under laboratory conditions. Their respective endmembers were extracted from ASTER imagery using the Pixel Purity Index (PPI). The endmembers were validated with in situ and laboratory thicket and bare-soil reflectance signatures. The spectral unmixing technique was applied to ASTER imagery to discriminate pure pixels of thicket vegetation and bare-soils; a residual spectral image was produced. The Residual Spectral Unmixing (RSU) procedure was applied to the residual spectral image to produce an RSU soil spectrum image. Partial Least Squares Regression (PSLR) model was developed using spectral signatures of a residual soil spectrum image as the independent variable and SOC concentration measured from soil samples as the dependent variable. The PSLR prediction model was used to predict SOC concentration on the RSU soil spectral image. The predicted SOC concentration was then validated with SOC concentration measured from the field plots. A Strong correlation (R2 = 0.82) was obtained between the predicted SOC concentration and the SOC concentration measured from field samples. The PSLR was then used to generate a map of SOC concentration for the Great Fish River Nature Reserve and its environs. Areas with very low SOC concentrations were found in the degraded communal villages, as opposed to the higher SOC values in the protected area. The results confirmed that RS techniques are key to estimating and mapping the spatial distribution of SOC concentration in partial subtropical thicket vegetation. Partial thicket vegetation has a huge influence on the soil spectra; it can influence the prediction of SOC concentration. The use of the RSU approach eliminates partial thicket vegetation cover from bare soil spectra. The residual soil spectrum image contains enough information for the mapping of SOC concentration. The technique has the potential to augment the applicability of airborne imaging spectroscopy for soil studies in the sub-tropical thicket biome and similar environments.
7

Improving strategies of food security in the face of environmental degradation in the Nelson Mandela Bay Municipality

Qoboshiyane, Vatiswa January 2013 (has links)
This research study examines the food security strategies adopted in the face of environmental degradation in the Nelson Mandela Bay Municipality (NMBM), South Africa. The NMBM is the only metropolitan municipality in the Eastern Cape Province. Over time, this area has experienced significant environmental degradation that has greatly affected food security. The municipality has responded by launching livelihood activities to promote food security and protect the environment. These include local food production projects and urban agricultural projects. This research study investigates whether or not the food security strategies adopted by the NMBM are sustainable and whether more needs to be done to enable the municipality to achieve its objectives. The study employed a mix of qualitative and quantitative methods, using interviews and questionnaires as the main tools for data collection. A sample of 20 participants was selected from the NMBM. The participants included municipal workers, private consultants, non-governmental organizations (NGOs) and an engineering firm working in the field of environmental sustainability. Their inputs are analyzed and discussed in order to arrive at the findings. Critical amongst the findings is that the NMBM should improve education on environmental issues. This should be geared towards building resilience to climate change which is the greatest environmental threat to food security.
8

Community-based environmentalism in transitional South Africa: social movements and the development of local democracy

Buchler, Michelle 30 January 2017 (has links)
A dissertation submitted to the Faculty of Arts at the University of the Witwatersrand, Johannesburg, in partial fulfilment for the degree of Master of Arts. Johannesburg 1995. / This report explores co llect+ve ect+on around opposition to a propo..;ed hazardous waste 1andf t 11. Of concern ;s the role that social movement organisations and social movement activists, organising around environmental issues, can play in entrenching a participatory, non-racial democracy in South Africa's present transitional political phase. The analysis makes use of theories of social movements which argue that collective action is rooted in previous cycles of mobilisation, and that the role of social movement entreprenbJrS or activists is crucial in coll,ctive action mob'l Hsat ton. Data was collected through the use of participant observation and semi-structured interviews, Various documentary sources were also used. This report argues that mobilisation around environmental issues can best be understood by locating such mobilisation in the heritage of previous cycles of mobilisation, most notably in the period of the 19805. Furthermore, this report highlights the fact that the structure and form of ~he transitional state at national, regional and local levels presents certain constraints with regard to the extension and entrenchment of participatory democracy, Finally, it will be argued that while the Chloorkop Coalition demonstrates the pctent ial that environmental issues have for uniting communities across traditional racial and ideological barriers, it ;s not clear whether a lasting cross~racial cooperation can be achieved. / MT2017
9

The application of a landscape diversity index using remote sensing and geographical information systems to identify degradation patterns in the Great Fish River Valley, Eastern Cape Province, South Africa

Tanser, Frank Courteney January 1997 (has links)
Using a range of satellite-derived indices I describe. monitor and predict vegetation conditions that exist in the Great Fish River Valley, Eastern Cape. The heterogeneous nature of the area necessitates that the mapping of vegetation classes be accomplished using a combination of a supervised approach, an unsupervised approach and the use of a Moving Standard Deviation Index (MSDI). Nine vegetation classes are identified and mapped at an accuracy of 84%. The vegetation classes are strongly related to land-use and the communal areas demonstrate a reduction in palatable species and a shift towards dominance by a single species. Nature reserves and commercial rangeland are by contrast dominated by good condition vegetation types. The Modified Soil Adjusted Vegetation Index (MSA VI) is used to map the vegetation production in the study area. The influence of soil reflectance is reduced using this index. The MSA VI proves to be a good predictor of vegetation condition in the higher rainfall areas but not in the more semi-arid regions. The MSA VI has a significant relationship to rainfall but no absolute relationship to biomass. However, a stratification approach (on the basis of vegetation type) reveals that the MSA VI exhibits relationships to biomass in vegetation types occurring in the higher rainfall areas and consisting of a large cover of shrubs. A technique based on an index which describes landscape spatial variability is presented to assist in the interpretation of landscape condition. The research outlines a method for degradation assessment which overcomes many of the problems associated with cost and repeatability. Indices that attempt to provide a correlation with net primary productivity, e.g. NDVI, do not consider changes in the quality of net primary productivity. Landscape variability represents a measure of ecosystem change in the landscape that underlies the degradation process. The hypothesis is that healthy/undisturbed/stable landscapes tend to be less variable and homogenous than their degraded heterogenous counterparts. The Moving Standard Deviation Index (MSDI) is calculated by performing a 3 x 3 moving standard deviation window across Landsat Thematic Mapper (TM) band 3. The result is a sensitive indicator of landscape condition which is not affected by moisture availability and vegetation type. The MSDI shows a significant negative relationship to NDVI confirming its relationship to condition. The cross-classification of MSDI with NDVI allows the identification of invasive woody weeds which exhibit strong photosynthetic signals and would therefore be categorised as good condition using NDVI. Other ecosystems are investigated to determine the relationship between NDVI and MSDI. Where increase in NDVI is disturbance-induced (such as the Kalahari Desert) the relationship is positive. Where high NDVI values are indicative of good condition rangeland (such as the Fish River Valley) the relationship is negative. The MSDI therefore always exhibits a significant positive relationship to degradation irrespective of the relationship of NDVI to condition in the ecosystem.
10

Legal analysis of the impact and consequences of environmental degradation in mining communities in South Africa

Makua, Pretty Maanate January 2017 (has links)
Thesis (LLM.) -- University of Limpopo, 2017 / Section 24 of the constitution of the Republic of South Africa, 1996 guarantees a right to a healthy and safe environment. It provides for the environment which is beneficial, conducive and productive to the community. However, this right is being violated on a daily basis by the mining companies which degrade the environment through their activities or operations within the mining communities by violating the legal regulations aimed at restoration, rehabilitation, management and prevention of degradation to the environment. Therefore this mini-dissertation advocate for stringent enforcement of the laws aimed at prevention of environmental degradation and further compels mining companies to comply with existing laws. It calls for the minister not to hesitate to revoke the mining licences or withdrawal of the mining permits of any erring mining companies. It utilises the jurisprudence from China and Australia as comparative study in order to draw relevant lessons from their approaches

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