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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.
351

A review of the social, economic and environmental impacts of the forestry industry in South Africa

Chown, Davin Loudon 30 June 2005 (has links)
Please read the abstract in the front section of this document / Dissertation (M Inst Agrar (Sustainable Ecological Management))--University of Pretoria, 2005. / Agricultural Economics, Extension and Rural Development / unrestricted
352

Habitat Evaluation Procedures at Ray Roberts Lake: an Analysis of the Relationship with Ecological Indicators and a Study of Observer and Temporal Variability

Wattrus, Jane M. (Jane Marie) 12 1900 (has links)
Habitat Evaluation Procedure data gathered at Ray Roberts Lake in 1989 and 1990 were analysed for temporal variability, observer variability and relationships between Habitat Units (HUs) and species density/diversity. observer variability within a group was analysed by cluster analysis and bootstrapping. Five out of 36 sites showed significant differences in Habitat Suitability Index (HSI) values within the group. A nonparametric Mann-Whitney test was used to analyze temporal variability. One of 6 sites showed a significant difference in HSI values between years. Using Spearman's Rank Correlation Coefficient, a correlation was found between indicator species density and HUs. No significant correlation was indicated between species diversity and HUs.
353

Liesbeeck-Black river confluence area : land-use opportunities and constraints

Bergman, Jan Gerhardus January 1994 (has links)
Bibliography: leaves 69-72. / This study investigated the land-use potential of the Liesbeeck-Black River confluence area . It is intended to serve as a guide to land-use planners and other interested parties concerning the opportunities and constraints proffered by the environment on the confluence area. The collecting of baseline data was undertaken by nine Masters Students in the Department of Environmental and Geographical Science at the University of Cape Town. Each student then analysed the data individually. The study was undertaken in part fulfilment of the academic requirements of the Masters Degree. The Liesbeeck-Black River confluence area (hereafter called the study area) is located approximately 5.5 km east of the CBD of Cape Town. It covers approximately 232 ha and is bounded by the N2 Freeway to the South, Alexandra Road to the East, Liesbeeck Parkway to the West and the Culemborg-Black River Railway Yard to the North. The aim of the study was twofold, firstly to determine a procedure whereby the optimal land- use alternative for an area could be determined, taking into account the effects of significant environmental elements, and secondly to analyse and determine the optimal land-use alternative for the study area specifically. The procedure developed during the research is an adaptation of the Leopold Matrix method of analysis. The environmental elements characteristic of the study area are listed on the horizontal axis, and the land-use options to be analysed on the vertical axis. The magnitude and significance of the effect of an environmental element on a particular type of land-use can then be rated and this rating entered in the corresponding matrix cell. By adding the ratings of all environmental elements on each land-use option, the overall rating of the different land-use options can be obtained. The option with the highest overall (positive) rating is then considered to be the optimal type of land-use. This method was then applied to assess the land-use potential of the study area. The land-use options considered to be appropriate for the study area were determined by considering only those types of land-uses for which a regional need had previously been established.
354

Integrating conservation and development : community participation in ecotourism projects : an investigation into community participation in ecotourism development projects in order to ensure the integration of protected area conservation and rural development, with particular reference to a case study at Cathedral Peak in the Natal Drakensberg Park

Theron, Izak Petrus January 1995 (has links)
This study arises out of a proposal of the Natal Parks Board (NPB) to develop a 200 bed hutted camp at Cathedral Peak in the Natal Drakensberg. In line with the NPB's stated commitment to the principles of Integrated Environmental Management (IEM), a multidisciplinary group, comprising five students from the Masters programme of the Department of Environmental and Geographical Sciences of the University of Cape Town, was commissioned to conduct a Preliminary Environmental Impact Assessment (PEIA) on the proposed development. The author was one of the members of this study team, hereafter referred to as the Masters Group, which conducted the PEIA at Cathedral Peak under the supervision of the Environmental Evaluation Unit of the University of Cape Town.
355

Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) in the Norwestern Atlantic

Pangallo, Kristin C January 2009 (has links)
Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2009. / Cataloged from PDF version of thesis. / Includes bibliographical references. / Halogenated 1'-methyl-1,2'-bipyrroles (MBPs) are a distinctive class of marine organic compounds. They are naturally produced, they have a unique carbon structure, they are highly halogenated, and they bioaccumulate in upper trophic levels. MBPs share many characteristics with persistent organic pollutants (POPs), and may prove to be useful natural analogues for these anthropogenic compounds. Further, their unique structure suggests that their biosynthetic organism(s) may have new genes to add to current knowledge of biosynthetic chemistry. The objectives of this dissertation were to further clarify the environmental distribution of MBPs, to examine whether MBPs biomagnify, and to investigate possible origins of these compounds through their stable nitrogen isotopic signatures. Results from these investigations have shown that over 40 highly brominated MBP congeners are present in marine mammals, fish, and squid from the Northwestern Atlantic Ocean. The most abundant MBPs do appear to biomagnify through the food web to reach the concentrations observed in marine mammals. This additional evidence affords greater confidence in the use of MBPs as natural analogues for POPs. However, differences in the environmental chemistry of MBPs and anthropogenic compounds are also evident, and may be due to these compounds' different origins, or to the capacity of degradative enzymes to act upon them. / (cont.) Finally, compound-specific nitrogen isotope analyses on MBPs isolated from dolphin blubber show that these compounds are dramatically enriched in 15N relative to other biosynthetic organic compounds. This enrichment is likely a signal imparted during biosynthesis, and may assist in elucidating the organism(s) and mechanism(s) responsible for the biosynthesis of MBPs. / by Kristin C. Pangallo. / Ph.D.
356

[en] ASSESSMENT OF THE MOBILITY OF ELEMENTAL CONTAMINANTS AND ENVIRONMENTAL IMPACTS DUE TO THE INAPPROPRIATE DISPOSAL OF FLUORESCENT LAMPS / [pt] AVALIAÇÃO DA MOBILIDADE DE CONTAMINANTES ELEMENTARES E IMPACTOS AMBIENTAIS DEVIDO AO DESCARTE INAPROPRIADO DE LÂMPADAS FLUORESCENTES

LAIS NASCIMENTO VIANA 07 August 2023 (has links)
[pt] Embora as lâmpadas fluorescentes (LF) estejam sendo substituídas por LED (diodo emissor de luz), a maioria das LF é descartada de forma inadequada e as taxas de reciclagem ainda são, em geral, baixas (4 por cento na China, 5 por cento no Brasil, 7 por cento no Canadá, menor que 10 por cento no Japão). Por causa da sua composição, as LF podem causar um impacto ambiental significativo. Assim, no presente estudo empregamos diferentes técnicas analíticas com o objetivo de caracterizar o material fosfórico bruto de LF, quantificar os elementos mobilizados por soluções de chorume e chuva ácida sintéticas, e avaliar os impactos ambientais relacionados ao descarte das lâmpadas através de análise de ciclo de vida (LCA) para o cenário da cidade do Rio de Janeiro. A análise do material bruto por fluorescência e difração de raios X (FRX e DRX) aponta uma composição de fases sólidas complexa, com predominância de Ca, P e Al, presença de elementos terras raras, As e outros. Através da extração ácida auxiliada por micro-ondas, concentrações em massa de 0,1 até 16,5 por cento foram encontradas para Al, Ba, Ce, Eu, La, Mn, P, Sr e Y no material bruto, e mais de 700 mg kg-1 de Hg. As lixiviações com as soluções sintéticas foram realizadas com e sem agitação, partindo de 0,6 g de amostra, 1 mL das soluções, e 3 h de exposição. O ensaio produziu a mobilização de diversos elementos com concentrações atingindo 23,5 mais ou menos 0,4 mg kg-1 (Hg) na chuva ácida, e 34,0 mais ou menos 1,0 mg kg-1 (Sr) no chorume. Devido à periculosidade de alguns elementos, as quantidades extraídas, apesar de baixas, são preocupantes, e lixiviações consecutivas, comuns num cenário real de descarte, podem agravar a situação. A análise de ciclo de vida apontou que as lâmpadas geram maiores impactos ambientais nas categorias de ecotoxicidade terrestre, toxicidade humana não-carcinogênica, potencial de aquecimento global e esgotamento de recursos fósseis. A análise indicou que o aumento das taxas de reciclagem pode reduzir em 70 a 90 por cento a maioria dos impactos ao meio ambiente. / [en] Although fluorescent lamps (FL) are being replaced by LED (light emitting diode), most FL are disposed of improperly and recycling rates are still generally low (4 percent in China, 5 percent in Brazil, 7 percent in Canada, less than 10 percent in Japan). Because of their composition, FL can have a significant environmental impact. Thus, in the present study, we used different analytical techniques with the objective of characterizing the raw phosphor material of FL, quantifying the elements mobilized by synthetic landfill leachate and acid rain solutions, and evaluating the environmental impacts related to the disposal of lamps through life cycle analysis (LCA) for the city of Rio de Janeiro scenario. The analysis of the raw material by fluorescence and X-ray diffraction (FRX and DRX) points to a complex composition of solid phases, with a predominance of Ca, P and Al, presence of rare earth elements, As and others. Through microwave-assisted near-total acid extraction, concentrations varying from 1 to 165 g kg-1 were found for Al, Ba, Ce, Eu, La, Mn, P, Sr, and Y in the raw material, and more than 700 mg kg-1 of Hg. Leaching with synthetic solutions was performed with and without agitation, with 0.6 g of sample, 1 mL of solutions, and 3 h of exposure. The test produced the mobilization of several elements with concentrations reaching 23.5 more or less 0.4 mg kg-1 (Hg) in acid rain, and 34.0 more or less 1.0 mg kg-1 (Sr) in landfill leachate. Due to the danger of some elements, the amounts extracted, although low, are worrying, and consecutive leaching, common in a real disposal scenario, can aggravate the situation. The life cycle analysis indicated that the lamps generate greater environmental impacts in the categories of terrestrial ecotoxicity, non-carcinogenic human toxicity, global warming potential and depletion of fossil resources. The analysis indicated that increasing recycling rates can reduce most impacts to the environment by 70 to 90 percent.
357

Environmental Study Of Solid Waste Collection

Maimoun, Mousa Awad 01 January 2011 (has links)
The growing municipal solid waste generation rates have necessitated more efficient, optimized waste collection facilities. The majority of the US collection fleet is composed of diesel-fueled vehicles which contribute significant atmospheric emissions including greenhouse gases. In order to reduce emissions to the atmosphere, more collection agencies are investigating alternative fuel technologies such as natural gas, biofuels (bio-gas and bio-diesel), and hybrid electric technology. This research is an in-depth environmental analysis of potential alternative fuel technologies for waste collection vehicles. This study will evaluate the use of alternative fuels by waste collection vehicles. Lifecycle emissions, cost, fuel and energy consumption were evaluated for a wide range of fossil and bio-fuel technologies. Moreover, the energy consumption and the tail-pipe emissions of dieselfueled waste collection vehicles were estimated using MOVES 2010a software. Emission factors were calculated for a typical waste collection driving cycle as well as constant speed. Finally, the selection of fuel type by the waste collection industry requires consideration of environmental, security, financial, operational, and safety issues. In this study, a qualitative comparison between alternative fuels was performed; a multifactorial assessment of these factors was conducted taking into account the opinion of the waste collection industry of the importance of each factor. Liquid-petroleum fuels have higher life-cycle emissions compared to natural gas; however landfill natural gas has the lowest life-cycle emissions compared to all other fuel categories. Compressed natural gas waste collection vehicles have the lowest fuel cost per collection vehicle mile travel compared to other fuel categories. Moreover, the actual driving cycle of waste collection vehicles consists of repetitive stops and starts during waste collection; iv this generates more emissions than constant speed driving. Finally, the multifactorial assessment indicates that natural gas and landfill gas have better environmental, economical, and energy security performance than current liquid-petroleum fuels.
358

Environmental mining frameworks for water pollution in the Democratic Republic of Congo and the Republic of South Africa

15 July 2015 (has links)
LL.M. (International Law) / Please refer to full text to view abstract
359

Ecological impact assessment: post-project analysis of pipeline installation.

January 2001 (has links)
Leung Hoi-gok. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 188-205). / Abstracts in English and Chinese. / Abstract --- p.i / 槪論 --- p.iv / Acknowledgements --- p.vi / List of Tables --- p.vii / List of Figures --- p.viii / List of Plates --- p.ix / List of Appendices --- p.x / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- The Problems --- p.6 / Chapter 1.3 --- Conceptual Framework --- p.10 / Chapter 1.4 --- Significance of the Study --- p.15 / Chapter 1.5 --- Scope of Study --- p.17 / Chapter 1.6 --- Organization of the Thesis --- p.19 / Chapter CHAPTER 2 --- STUDY AREA / Chapter 2.1 --- Physical Setting of Hong Kong --- p.22 / Chapter 2.2 --- "Towngas Pipeline Project, the Land Section" --- p.25 / Chapter 2.3 --- Study Plots --- p.30 / Chapter 2.4 --- Observation on the Site --- p.39 / Chapter 2.5 --- Post-planting Care --- p.40 / Chapter CHAPTER 3 --- SOIL PROPERTIES AND IMPACTS BY PIPELINE CONSTRUCTION / Chapter 3.1 --- Introduction --- p.42 / Chapter 3.2 --- Methodology --- p.47 / Chapter 3.2.1 --- Sampling --- p.47 / Chapter 3.2.2 --- Bulk density --- p.48 / Chapter 3.2.3 --- Soil texture --- p.43 / Chapter 3.2.4 --- Soil reaction --- p.49 / Chapter 3.2.5 --- Organic carbon --- p.49 / Chapter 3.2.6 --- Total Kjedahl nitrogen (TKN) --- p.50 / Chapter 3.2.7 --- Available phosphate --- p.50 / Chapter 3.2.8 --- "Exchangeable K, Ca and Mg" --- p.50 / Chapter 3.3 --- Statistical Analysis --- p.51 / Chapter 3.4 --- Results --- p.51 / Chapter 3.4.1 --- Soil texture --- p.51 / Chapter 3.4.2 --- Bulk density --- p.53 / Chapter 3.4.3 --- Soil pH --- p.53 / Chapter 3.4.4 --- Soil organic matter --- p.55 / Chapter 3.4.5 --- Total Kjeldahl nitrogen --- p.55 / Chapter 3.4.6 --- Available phosphorus --- p.59 / Chapter 3.4.7 --- "Exchangeable potassium, calcium and magnesium ions" --- p.59 / Chapter 3.5 --- Discussion --- p.64 / Chapter 3.5.1 --- Nutrient content of shoulder and proper soils --- p.64 / Chapter 3.5.2 --- Causes for the change of soil properties --- p.72 / Chapter 3.5.2.1 --- Construction of the pipeline --- p.72 / Chapter 3.5.2.2 --- Influence of localized factors --- p.74 / Chapter 3.5.3 --- Recommendations on soil management --- p.75 / Chapter 3.6 --- Conclusion --- p.77 / Chapter CHAPTER 4 --- SPECIES SELECTION IN RESTORATION PLANTING / Chapter 4.1 --- Introduction --- p.79 / Chapter 4.2 --- Methodology --- p.83 / Chapter 4.2.1 --- Vegetation sampling --- p.83 / Chapter 4.3 --- Results --- p.85 / Chapter 4.3.1 --- Species composition of the undisturbed habitats --- p.85 / Chapter 4.3.2 --- Species composition of the restored vegetation --- p.88 / Chapter 4.4 --- Discussion --- p.95 / Chapter 4.4.1 --- Inadequate baseline and impact prediction in project EIA --- p.95 / Chapter 4.4.2 --- Restoration strategy --- p.98 / Chapter 4.4.3 --- Species selection in restoration planting --- p.101 / Chapter 4.4.4 --- Compatibility of species in restoration planting --- p.105 / Chapter 4.5 --- Conclusion --- p.110 / Chapter CHAPTER 5 --- GROWTH PERFORMANCE OF VEGETATION AND NATURAL INVASION IN THE SITES / Chapter 5.1 --- Introduction --- p.112 / Chapter 5.2 --- Methodology --- p.117 / Chapter 5.3 --- Results --- p.119 / Chapter 5.3.1 --- Growth performance of shrubs and trees --- p.119 / Chapter 5.3.2 --- Ground cover --- p.131 / Chapter 5.3.3 --- Species invading the pipeline corridor --- p.132 / Chapter 5.4 --- Discussion --- p.133 / Chapter 5.4.1 --- Growth performance of the restored saplings --- p.133 / Chapter 5.4.2 --- Site constraints --- p.135 / Chapter 5.4.3 --- Natural invasion on the pipeline corridor --- p.140 / Chapter 5.5 --- Conclusion --- p.141 / Chapter CHAPTER 6 --- RESTORATION TECHNIQUES AND MANAGEMENT / Chapter 6.1 --- Introduction --- p.144 / Chapter 6.2 --- Overview of the Project EIA --- p.146 / Chapter 6.2.1 --- Guidelines for site preparation --- p.146 / Chapter 6.2.2 --- Planting techniques of the restored vegetation --- p.148 / Chapter 6.2.3 --- Maintenance and aftercare --- p.149 / Chapter 6.3 --- Evaluation on Restoration Techniques and Aftercare --- p.149 / Chapter 6.3.1 --- Site preparation --- p.149 / Chapter 6.3.2 --- Restoration techniques of the vegetation --- p.151 / Chapter 6.4 --- Conclusion --- p.153 / Chapter CHAPTER 7 --- IMPROVEMENT ON ECOLOGICAL IMPACT ASSESSMENT / Chapter 7.1 --- Introduction --- p.154 / Chapter 7.2 --- Integrative Discussion --- p.156 / Chapter 7.2.1 --- Scoping and focusing procedures --- p.156 / Chapter 7.2.2 --- Impact assessment --- p.160 / Chapter 7.2.3 --- Impact mitigation --- p.161 / Chapter 7.2.4 --- Monitoring and auditing --- p.165 / Chapter 7.2.5 --- Guidelines of restoration in the technical memorandum of EIAO --- p.167 / Chapter 7.3 --- Conclusion --- p.169 / Chapter CHAPTER 8 --- CONCLUSION / Chapter 8.1 --- Summary of Findings --- p.171 / Chapter 8.2 --- Implications of the Study --- p.179 / Chapter 8.2.1 --- Criteria for the selection of species in restoration --- p.179 / Chapter 8.2.2 --- Silvicultural knowledge of native species --- p.180 / Chapter 8.2.3 --- Soil impact assessment for project involving soil alternation --- p.182 / Chapter 8.2.4 --- Improvement on environmental monitoring and auditing --- p.182 / Chapter 8.3 --- Limitation of the Study --- p.183 / Chapter 8.4 --- Suggestion for Further Studies --- p.185 / REFERENCES --- p.188 / APPENDICES --- p.206
360

Mkhondeni Stream Catchment Area Strategic Environmental Assessment : an examination of governance processes with particular reference to public participation.

Abboy, Cassandra S. January 2008 (has links)
In recent years within South Africa, good governance has become a governmental goal with sound public participation processes becoming a core element of good governance practices. As a result of this goal, most decision-making tools have an element of public participation within them: a Strategic Environmental Assessment (SEA) is one such tool. This study aimed to examine the governance processes within the draft Mkhondeni Stream Catchment (MSC) area SEA with particular reference to public participation. Five objectives were conceived to achieve this aim. The first objective involved an examination of the public participation processes as articulated by the legislation. The second objective involved an examination of the public participation processes of the draft MSC area SEA. The third objective was to determine whether the ‘deliberation’ or public participation process was adequate. The fourth objective was to investigate how the draft MSC area SEA was framed and reframed by key stakeholders. The fifth and last objective of this study was to reflect on the public participation process and how it may be strengthened. Against the background of a focused literature review on good governance practices, public participation and SEAs, the fieldwork undertaken involved a qualitative approach using key informant interviews and random community member’s interviews. The key informant interviews were held with what are widely considered to be the key stakeholders within the MSC area SEA process. Random interviews were held with Ashburton community members to add value to this study by allowing for a wider perspective from general community members to be understood. There were 5 objectives that are set out for this study and they were achieved. Objective 1 is achieved through an examination into the public participation processes as articulated by the Provincial Department of Environmental Affairs and Tourism (DEAT) and legislation. The findings reveal that there is sufficient legislation and processes with regards to public participation in terms of Environmental Impact Assessments (EIAs); however it is noted that there is a lack of clarity with regards to the public participation processes and legislation within the SEA process and at present there are only recommendations for best practice. Objective 2 and 3 are achieved as they dealt with the understanding and adequacy of the public participation processes within the draft Mkhondeni SEA. The findings generated allow for the public participation methods and process used to be noted and in relation to the methods and process used the public participation process was deemed to be inadequate as it did not meet the minimum requirements stipulated by legislation in terms of public participation within an environmental assessment as well as the recommendations for best practice. Objective 4 is achieved by investigating how the draft SEA is framed by the key stakeholders. Out of the results the emerging themes that were identified within this study were that of: (a) Misrepresentation of the community by the Preservation of the Mkondeni Mpushini Biodiversity Trust (PMMBT); (b) the SEA being viewed as a learning process in which a lack of clarity emerged amongst interested and affected parties (I & APs) about the exact process that needed to be carried out to achieve the SEA; (c) a lack of trust in the government to take the comments of the community into consideration; (d) the importance of education within society about environmental tools, such as the SEA, and their uses; and (e) the need for social development to be considered alongside environmental concerns within the Ashburton area. And lastly, objective 5 is achieved as the public participation process within the draft SEA is reflected upon and recommendations are made. These recommendations deal with the following: (1) Involvement in the Formulation of the ToR, (2) Identification of I & APs, (3) Feedback, (4) Capacity Building and Education needs and (5) Management of the SEA Process. The intention of the researcher is that the knowledge derived from engaging with interviewees and from researching relevant literature will be used to improve future decision-making processes with the overall aim of improving the relationship between the relevant authorities and communities affected by so-called development. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

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