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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

Innovative coupling of hydrological modelling for IWRM: linking catchment functioning with socio-economic conditions in the Olifants

Magombeyi, Manuel Simba 12 May 2011 (has links)
Computerised integrated models from science contribute to better informed and holistic exante integrated assessments of multifaceted policies and technologies. This view has lead to considerable effort being devoted to developing integrated models to support decisionmaking under Integrated Water Resources Management (IWRM). Nevertheless, an appraisal of previous and ongoing efforts to develop such decision support systems shows that attempts to address the hydro-socio-economic effects on livelihoods have been deficient and fragmented. To date, no universal standard integration method or framework is in use. Existing integrated models application failures have pointed to the lack of stakeholder participation. In an endeavour to close this gap, this thesis focuses on an integrated model development with prediction capability, ICHSEA, developed in Avenues script language in ArcView 3.3, to take advantage of the mapping capability of ArcView. This model couples existing hydrology (SWAT), agronomy (PARCHED-THIRST) and socio-economic (OLYMPE) models to link livelihoods of resource-constrained smallholder farmers to water resources availability at catchment level in the semi-arid Olifants subbasin, South Africa. These three models were calibrated and validated using observed data and local stakeholder participation, prior to coupling in the integrated model. All the models performed well in representing the study conditions, as indicated by the statistical performance. The integrated model is generally applicable to any catchment. The study methodology was inspired by the need to enhance rural livelihoods and to close the gap of stakeholder involvement in building and applying integrated models to ensure acceptability and application in decision-making. Over 20 years, the predicted impacts of untied ridges and planting basins versus conventional rainfed tillage on surface runoff reduction were 14.3 % and 19.8 %, respectively, and about 41─46 % sediment yield reduction in the catchment. At 90 % confidence interval, family savings improved from US$ 4─US$ 270 under conventional rainfed to US$ 233─US$ 1 140 under supplemental irrigation. These results underscore the economic and environmental benefits that could be achieved by adopting the new crop management practices. A relationship between maize crop evapotranspiration and family savings under different crop management strategies was also derived for five farm typologies in the catchment.
2

Valuing the Environmental Benefits from GM Products Using an Experimental Procedure: Lessons From the United States and the Philippines

Maupin, Jason Derek 15 January 2007 (has links)
This thesis develops an experimental procedure to value the environmental benefits from two pre-production genetically modified (GM) products, MVR tomatoes and Bt eggplant. The procedure explicitly tells subjects the GM nature of the products, and frames the value as an actual donation to the scientific organization pursuing the product research. The procedure is tested in the United States and the Philippines. The tests suggest that United States students give significantly different values than Filipino farmers with Filipino farmers valuing the environmental benefits much higher than United States students. The tests also suggest that slight changes in procedures can significantly affect values. Subjects also use information learned during the experiment to form their valuations. For example, Filipino farmers significantly increase their values as the procedure progresses. / Master of Science
3

Valuing environmental benefits using the contingent valuation method : an econometric analysis

Kriström, Bengt January 1990 (has links)
The purpose of this study is to investigate methods for assessing the value people place on preserving our natural environments and resources. It focuses on the contingent valuation method, which is a method for directly asking people about their preferences. In particular, the study focuses on the use of discrete response data in contingent valuation experiments.The first part of the study explores the economic theory of the total value of a natural resource, where the principal components of total value are analyzed; use values and non-use values. Our application is a study of the value Swedes' attach to the preservation of eleven forest areas that contain high recreational values and contain unique environmental qualities. Six forests were selected on the basis of an official investigation which includes virgin forests and other areas with unique environmental qualities. In addition, five virgin forests were selected.Two types of valuation questions are analyzed, the continuous and the discrete. The first type of question asks directly about willingness to pay, while the second type suggests a price that the respondent may reject or accept. The results of the continuous question suggest an average willingness to pay of about 1,000 SEK per household for preservation of the areas. Further analysis of the data suggests that this value depends on severi characteristics of the respondent: such as the respondent's income and whether or not the respondent is an altruist.Two econometric approaches are used to analyze the discrete responses; a flexible parametric approach and a non-parametric approach. In addition, a Bayesian approach is described. It is shown that the results of a contingent valuation experiment may depend to some extent on the choice of the probability model. A re-sampling approach and a Monte-Carlo approach is used to shed light on the design of a contingent valuation experiment with discrete responses. The econometric analysis ends with an analysis of the often observed disparity between discrete and continuous valuation questions.A cost-benefit analysis is performed in the final chapter. The purpose of this analysis is to illustrate how the contingent valuation approach may be combined with opportunity cost data to improve the decision-basis in the environmental policy domain. This analysis does not give strong support for a cutting alternative. Finally, the results of this investigation are compared with evidence from other studies.The main conclusion of this study is that assessment of peoples' sentiments towards changes of our natural environments and resources can be a useful supplement to decisions about the proper husbandry of our natural environments and resources. It also highlights the importance of careful statistical analysis of data gained from contingent valuation experiments. / digitalisering@umu
4

A Contingent Valuation of Tampa’s Urban Forest Resource

Foster, Alec 18 October 2010 (has links)
Urban forests provide environmental, social, and economic benefits to urban residents. These benefits are often overlooked when making spatial and financial distributive decisions in urban areas. The City of Tampa has demonstrated interest in its urban forest resource and estimated its extent and some of the benefits provided. Estimating economic values for benefits that have not been quantified can help to ensure that resources are distributed more efficiently. Five methods to estimate urban forest benefits in the City of Tampa are reviewed, with contingent valuation being the method chosen out of this review process. A mailed, dichotomous choice contingent valuation survey was executed with two points of contact, yielding 107 responses for a 21.4 percent response rate. Despite positively rating the City’s urban forest, the majority of respondents (62.6 percent) were willing to pay for it to increase. The Turnbull distribution-free estimator was used to estimate a lower bound of $3.23 for willingness to pay to increase Tampa’s urban forest resource by 250,000 trees. Willingness to pay was positively associated with income and education. The survey responses also yielded important attitudinal and behavioral information that can help local decision makers increase the efficiency of urban forest distribution, maintenance, and promotion.
5

Analyzing trends of asphalt recycling in France

Schvallinger, Mathias January 2011 (has links)
In France, road transport accounts for 50% and 30% of the NOx and CO2 emissions respectively. Asphalt recycling consists in including Reclaimed Asphalt Pavement (RAP) into new Asphalt Concrete. This technique can allow firms in the road construction field to reduce their impacts on the environment and thus to achieve the goals set by the European Commission. Unfortunately, asphalt recycling just began to have more importance in France. Additionally, the lack of easily available data and studies about this method makes it complicated to enhance the development of asphalt recycling. The thesis aimed to picture a good overview of the current asphalt recycling practices in France and to analyze them from an environmental point of view. The main attention was concentrated on GreenHouse Gases (GHGs) emissions and energy consumptions of those techniques. Moreover, the thesis tried to describe the main advantages and drawbacks of the different asphalt recycling techniques in order to understand their proportions in France. The study also aimed to learn from the experiences of other regions by comparing the French practices with other European countries and analyzing these differences. The methodology used is literature review, interviews and use of a Life Cycle Assessment (LCA) tool: asPECT.  The literature review provided all the theoretical background needed to understand asphalt recycling and also data about its impacts on the environment. In order to add a current component that reflects the reality of road constructions firms, data was also collected with interviews and interpreted with the LCA tool. Finally, the LCA approach was used to compare and analyze all the results collected by providing the necessary simplifications. Study results show that France increased its proportion of RAP recycled significantly lately to reach 63%. The main two asphalt recycling techniques used are Hot In-Plant recycling and Cold In-Place Recycling (CIR). CIR is the most environmental friendly asphalt recycling technique, reaching a reduction of 80% in GHGs emissions and energy consumptions compared to a classical rehabilitation method. Hot In-Plant recycling only allows a reduction of approximately 30% in the same environmental factors. Thanks to those techniques 113 000 tons of CO2e and 10,3 * 105 GJ have been saved in 2010. Asphalt recycling also enables making economic profits and improving social conditions. However, pollutants, tar or asbestos contaminated asphalt, haulage distance limit the development of asphalt recycling in France. It was also observed that France is behind its neighbors but is catching up lately. The main reasons for this delay are the aggregates’ supplies; the number of plants fit for recycling and the legislation about waste disposal and RAP recycling rates. It was concluded that to enhance the use of asphalt recycling in France, French authorities, research centers, road construction firms and certification organisms have to cooperate and work together in order to stem the main drawbacks of asphalt recycling, settle the LCA problems, to win the trust of the State and the firms and to increase the competition.
6

The Fiction of Globally Important Biodiversity: The Production of Scale through the Global Environment Facility’s Biodiversity Policy and Programming

Barnes, Julia Clare 14 December 2010 (has links)
The gap observed between the rhetoric and reality of biodiversity conservation draws critical attention to the discourse of conservation and to claims that local and global interests can be balanced. In this work, I suggest that the spatial framing of organized biodiversity conservation inhibits attempts to produce such 'balance'. I examine the processes by which biodiversity conservation projects are brought into being through the discursive production of scale within the institutional framework of the Global Environment Facility (GEF). Using five case studies of projects proposed under the GEF’s operational program for agrobiodiversity, I analyze how the GEF brings actors and sites into relation and engages them in the reproduction of articulations of scale through the GEF project cycle. In so doing, I reveal how the mechanisms that structure conservation projects around global goals systematically undermine the claims of situated resource users and prevent questions of justice from being raised.
7

The Fiction of Globally Important Biodiversity: The Production of Scale through the Global Environment Facility’s Biodiversity Policy and Programming

Barnes, Julia Clare 14 December 2010 (has links)
The gap observed between the rhetoric and reality of biodiversity conservation draws critical attention to the discourse of conservation and to claims that local and global interests can be balanced. In this work, I suggest that the spatial framing of organized biodiversity conservation inhibits attempts to produce such 'balance'. I examine the processes by which biodiversity conservation projects are brought into being through the discursive production of scale within the institutional framework of the Global Environment Facility (GEF). Using five case studies of projects proposed under the GEF’s operational program for agrobiodiversity, I analyze how the GEF brings actors and sites into relation and engages them in the reproduction of articulations of scale through the GEF project cycle. In so doing, I reveal how the mechanisms that structure conservation projects around global goals systematically undermine the claims of situated resource users and prevent questions of justice from being raised.
8

Quantificação dos impactos econômicos e ambientais decorrentes do estado de conservação das rodovias brasileiras / Quantifying of the economic and environmental impacts deriving from Brazilian\'s highways state of conservation

Bartholomeu, Daniela Bacchi 21 November 2006 (has links)
Devido à importância do modal rodoviário para a economia brasileira no que diz respeito à sua participação na matriz de transporte de cargas, à elevada participação no consumo de combustíveis fósseis (óleo diesel) e nas emissões de CO2, esta Tese avaliou se rodovias em melhores estados de conservação implicam benefícios econômicos e ambientais. Os benefícios econômicos disseram respeito à avaliação dos seguintes parâmetros: consumo de combustível, tempo de viagem e gasto com manutenção do veículo. Já os benefícios ambientais referiram-se às reduções das externalidades negativas resultantes da diminuição nas emissões de CO2. Foram realizadas coletas de dados primários relacionados ao desempenho observado em caminhões em rodovias com diferentes condições de infra-estrutura. Nesse sentido, foram conduzidos dois conjuntos de experimentos, envolvendo rotas e tipos diferentes de caminhões, aos quais foram acoplados computadores de bordo para auxiliar na coleta dos dados. O primeiro conjunto de experimentos envolveu quatro rotas, as quais foram percorridas por um caminhão Volvo FH12, fabricado em 2004. Num total de 48 viagens, foram observados o consumo de combustível, e o perfil das velocidades em cada trajeto. Os resultados indicaram a existência de benefícios econômicos e ambientais para as rotas em melhor estado de conservação. No segundo conjunto de experimentos, foram selecionadas duas rotas em diferentes estados de conservação., nas quais dois caminhões de fabricantes distintos (Scania R124-420 e MB 1944S) realizaram um total de 40 viagens. Nesses experimentos, também foram comparados os resultados observados em cada tipo de veículo, tendo sido possível concluir que o tipo de tecnologia apenas impactou no consumo de combustível. Finalmente, os dados dos dois conjuntos de experimentos foram agregados, a fim de estimar valores mais próximos à realidade, já que na prática, há diversos tipos de modelos e fabricantes de caminhão. Ainda assim, os resultados obtidos confirmam a existência de benefícios econômicos e ambientais resultantes de viagens em rotas com melhor infra-estrutura: há um aumento na eficiência energética em rotas melhores, implicando menor consumo de combustível e menores níveis de emissão de CO2. A análise estatística dos resultados sugeriu que, em geral, os dados relacionados ao consumo de combustível eram significativos ao nível de significância de 5%, rejeitando a hipótese nula de que o consumo médio das rotas em piores estados de conservação é estatisticamente igual ao consumo médio observado em rotas com melhores condições. Portanto, tratou-se de indicação em favor da hipótese alternativa, de que o consumo médio observado em rotas piores é maior do que aquele em rotas melhores. / Due to importance of the road transportation for the Brazilian economy related to its participation in the matrix of load transport, to its high participation in the fossil fuels consumption (diesel) and in the CO2 emissions, this study evaluated if highways in better state of conservation imply in economic and environmental benefits. The economic benefits were related to the evaluation of the following parameters: fuel consumption, duration of the trip and expenses on vehicle maintenance. The environmental benefits related to the CO2 emissions reduction. It was collected primary data related to the performance observed in trucks on highways with different infrastructure conditions. In this aspect, it was carried out two sets of experiments, involving different routes and types of trucks, to which cutting edge computers were connect to assist the collection of the data. The first set of experiments involved four routes covered by a Volvo FH12 truck, manufactured in 2004. In a total of 48 trips, the fuel consumption, and the velocity profile in each passage were observed. The results showed the existence of economic and environmental benefits in the routes with better conservation. In the second set of experiments, two routes in different states of conservation were selected, in which two trucks from distinct manufacturers (Scania R124-420 and MB 1944S) performed a total of 40 trips. In these experiments, the results observed in each type of vehicle were compared, which allowed to conclude that the type of technology only impacted on the fuel consumption. Finally, the data of the two sets of experiments were aggregated, in order to approximate the values to the reality, once in reality there are several types of truck models and manufacturers. Still, the results confirm the existence of economic and environmental benefits deriving from trips in routes with better infrastructure: there is a gain in energy efficiency, resulting in less fuel consumption and lower levels of CO2 emissions. The statistical analysis of the results suggested that, in general, the data related to the fuel consumption were significant to the level of significance of 5%, rejecting the null hypothesis that the average fuel consumption in the routes in worse states of conservation is statistically equal to that observed in routes in better condition. Therefore, it is indicated that the alternative hypothesis is significant that the observed average consumption in worse routes is bigger than that observed in better routes.
9

Serviços ambientai$ em Pelotas-RS : a reciclagem de resíduos sólidos secos

Amaro, Aurélio Bandeira January 2014 (has links)
O presente trabalho trata de uma pesquisa apresentada como dissertação para obtenção do título de mestre em Geografia. O estudo foi realizado na cidade de Pelotas – Rio Grande do Sul – Brasil, e se justifica pela recente aprovação da Lei nº 12.305/2010, que institui a Política Nacional de Resíduos Sólidos. Seu tema principal é a tentativa de mensuração dos benefícios gerados pela atividade de reciclagem de resíduos sólidos secos nesta cidade. Para isso, utilizou-se como principais bases teórico-metodológicas estudosque abordam os benefícios ambientais proporcionados e desperdiçados pela prática da (não) reciclagem de resíduos no Brasil. Os resultados permitem dizer que a cidade – através da coleta seletiva pública, dos catadores e dos compradores de recicláveis – reinsere, mensalmente, em torno de 2,2 mil toneladas de materiais no ciclo produtivo, com benefícios ambientais da ordem de R$ 19 milhões/ano. Também foi feito um balanço sobre o quanto é perdido pela não reciclagem dos resíduos, estando esse valor na ordem de R$ 16 milhões/ano. / This research is presented as a dissertation in order to obtain the Masters degree in Geography. The study was conducted in the city of Pelotas - Rio Grande do Sul - Brazil, and it is justified because of the recent approval of the Law n º 12.305/2010, which establishes the Solid Waste National Policy. The main theme is based on the attempt to measure the benefits generated by the dry solid waste recycling in the mentioned city. It was used, as the main theoretical and methodological basis, studies that issues the wasted enviromental benefits that results from (not) recycling solid in Brazil. Results allow to state that, through public collective selection, waste pickers and recyclable material buyers, is reintegrated in a monthly basis the total about of 2.2 thousand tons of material included in the productive cycle, obtaining an environmental profit of approximately R$ 19 Million peryear. It was also made an assessment on how much is lost by not recycling, getting a cost value of R$ 16million. / El presente trabajo es una investigación presentada a modo de disertación para obtener el título de Maestro en Geografía. El estudio fue realizado en la ciudad de Pelotas - Rio Grande do Sul - Brasil, y está justificado por la reciente aprobación de la Ley n 12.305/2010, que constituye la Política Nacional de Residuos Sólidos. El tema principal se basa en la tentativa de medir los beneficios generados por el reciclaje de residuos sólidos secos en dicha ciudad. Para eso se utilizaron, como principal base teórica y metodológica, las premisas adoptadas en el libro Los resultados permiten decir que la ciudad - a través de la colecta selectiva pública, de los recolectores y los compradores de materiales reciclables - reinserta mensualmente entorno de 2,2 mil toneladas de material en el ciclo productivo, consiguiendo un beneficio ambiental expresado en un monto aproximado de R$ 19 millones/ano. También fue realizado un balance sobre cuanto se pierde al no reciclar los residuos, obteniendo un valor aproximado de R$ 16 millones/año.
10

Serviços ambientai$ em Pelotas-RS : a reciclagem de resíduos sólidos secos

Amaro, Aurélio Bandeira January 2014 (has links)
O presente trabalho trata de uma pesquisa apresentada como dissertação para obtenção do título de mestre em Geografia. O estudo foi realizado na cidade de Pelotas – Rio Grande do Sul – Brasil, e se justifica pela recente aprovação da Lei nº 12.305/2010, que institui a Política Nacional de Resíduos Sólidos. Seu tema principal é a tentativa de mensuração dos benefícios gerados pela atividade de reciclagem de resíduos sólidos secos nesta cidade. Para isso, utilizou-se como principais bases teórico-metodológicas estudosque abordam os benefícios ambientais proporcionados e desperdiçados pela prática da (não) reciclagem de resíduos no Brasil. Os resultados permitem dizer que a cidade – através da coleta seletiva pública, dos catadores e dos compradores de recicláveis – reinsere, mensalmente, em torno de 2,2 mil toneladas de materiais no ciclo produtivo, com benefícios ambientais da ordem de R$ 19 milhões/ano. Também foi feito um balanço sobre o quanto é perdido pela não reciclagem dos resíduos, estando esse valor na ordem de R$ 16 milhões/ano. / This research is presented as a dissertation in order to obtain the Masters degree in Geography. The study was conducted in the city of Pelotas - Rio Grande do Sul - Brazil, and it is justified because of the recent approval of the Law n º 12.305/2010, which establishes the Solid Waste National Policy. The main theme is based on the attempt to measure the benefits generated by the dry solid waste recycling in the mentioned city. It was used, as the main theoretical and methodological basis, studies that issues the wasted enviromental benefits that results from (not) recycling solid in Brazil. Results allow to state that, through public collective selection, waste pickers and recyclable material buyers, is reintegrated in a monthly basis the total about of 2.2 thousand tons of material included in the productive cycle, obtaining an environmental profit of approximately R$ 19 Million peryear. It was also made an assessment on how much is lost by not recycling, getting a cost value of R$ 16million. / El presente trabajo es una investigación presentada a modo de disertación para obtener el título de Maestro en Geografía. El estudio fue realizado en la ciudad de Pelotas - Rio Grande do Sul - Brasil, y está justificado por la reciente aprobación de la Ley n 12.305/2010, que constituye la Política Nacional de Residuos Sólidos. El tema principal se basa en la tentativa de medir los beneficios generados por el reciclaje de residuos sólidos secos en dicha ciudad. Para eso se utilizaron, como principal base teórica y metodológica, las premisas adoptadas en el libro Los resultados permiten decir que la ciudad - a través de la colecta selectiva pública, de los recolectores y los compradores de materiales reciclables - reinserta mensualmente entorno de 2,2 mil toneladas de material en el ciclo productivo, consiguiendo un beneficio ambiental expresado en un monto aproximado de R$ 19 millones/ano. También fue realizado un balance sobre cuanto se pierde al no reciclar los residuos, obteniendo un valor aproximado de R$ 16 millones/año.

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