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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.
41

Assessing Water Management Impacts of Climate Change for a Semi-arid Watershed in the Southwestern US

Rajagopal, Seshadri January 2012 (has links)
Water managers for the City of Phoenix face the need to make informed policy decisions regarding long-term impacts of climate change on the Salt-Verde River basin. To provide a scientifically informed basis for this, we estimate the evolution of important components of the basin-scale water balance through the end of the 21st century. Bias-corrected and spatially downscaled climate projections from the Phase-3 Coupled Model Intercomparison Project of the World Climate Research Programme were used to drive a spatially distributed variable infiltration capacity model of the hydrologic processes in the Salt-Verde basin. From the many Global Climate Model's participating in the IPCC fourth assessment, we selected a five-model ensemble, including three that best reproduce the historical climatology for our study region, plus two others to represent wetter and drier than model average conditions; the latter two were requested by City of Phoenix water managers to more fully represent the full range of GCM prediction uncertainty. For each GCM, data for three emission scenarios (A1B, A2, B1) was used to drive the hydrologic model into the future. The model projections indicate a statistically significant 25% decrease in streamflow by the end of the 21st century. Contrary to previous assessments, this is not caused primarily by changes in the P/E ratio, but is found to result mainly from decreased winter precipitation accompanied by significant (temperature driven) reductions in storage of snow. The results show clearly the manner in which water management in central Arizona is likely to be impacted by changes in regional climate.
42

Santa Fe Ski Basin Proposed Expansion Ethnographic Assessment

Evans, Michael, Stoffle, Richard W., Krause, Elizabeth 01 June 1993 (has links)
The purpose of this research study was to conduct an ethnographic assessment for an Environmental Impact Statement (EIS) of a proposed expansion plan for the Santa Fe Ski Area located in the Sangre de Cristo Mountains north of Santa Fe, New Mexico. Along with expansion into forest areas outside the existing Special Use permit boundaries, the proposed plan includes new buildings, parking lots, lifts, ski runs, and snowmaking within the existing ski area boundary. The ethnographic assessment concentrates on those cultural resources known to be in the area, as identified by Pueblo participants in the research study. This project had three objectives: a) what impact would the project have on the traditional uses, cultural uses, values, and belief practices of Tesuque Pueblo and other Pueblos' uses of the area; b) how would the ski area expansion affect the traditional use area of the Tesuque Pueblo and other Pueblos; and c) what specific areas of traditional cultural use, including those of Hispanic origin, would be affected by the proposed alternatives.
43

A comparison of the environmental impact assessment legislation of South Africa and Malawi / by M.A.C. Harrison

Harrison, Margaret Anne Collins January 2005 (has links)
It is generally accepted that the environment has three inter-dependent components: economic, socio-political and natural Consequently, integrated environmental management coupled with sustainable development is critical, and in order to achieve this goal, effective guidelines and implementable legislation are necessary. This evaluation aims to determine and compare the effectiveness of the South African and Malawian environmental impact assessment (EIA) legislation, using the comparative criteria set out by Wood (1995, 2003), and accordingly to determine whether any further amendments are necessary to improve the effectiveness of these countries' EIA systems. In the Southern African Development Community (SADC) region, it is particularly important that environmental legislation and policies are aligned across borders, to allow for better integration of these economies. The alignment of EIA systems in the SADC region could enhance regional sustainable development if managed using similar criteria. The primary objective of this study is to compare the EIA legislation of South Africa and Malawi using Wood's (1995, 1999, 2003) 14-point evaluation criteria. The effectiveness and not the implementation and practice of the legislation is being compared. The secondary objective of this study is to determine whether Wood and Roux's recommendations have been incorporated into the South African National Environmental Management Amendment Act 8 of 2004 and the January 2005 draft EIA regulations, and whether South African legislation meets Wood's 14 criteria for a sound EIA system. In the South African evaluation, 11 of Wood's 14 criteria are met, while an additional two criteria are partially met and one criterion is failed, resulting in an overall improvement in the South African EIA system. The Malawian EIA legislation meets 11 of Wood's 14 criteria, with three criteria being partially met, in principle making it more effective than the South African EIA legislation. However, although Malawi theoretically has a slightly more effective EIA legislation than South Africa, in practice this is not the case. Ideally, when South Africa's updated EIA legislation is published it will meet with all 14 of Wood's criteria for an effective EIA system based on international standards. / Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2006.
44

Exposure to particulate matter and the related health impacts in major Estonian cities

Orru, Hans January 2009 (has links)
Particulate matter (PM) is one of the most studied and problematic pollutants due to its toxicity and relati­vely high concentrations. This thesis aims to clarify the main sources and exposures of PM in Tallinn and Tartu, study the associations with health effects, and estimate the extent of those effects with health impact assessment (HIA). It appeared that the main sources of particulate air pollution in Tallinn (the capital of Estonia) and Tartu (the second largest city of Estonia) are local heating and traffic, inclu­ding road dust. In addition to local emissions, particulate levels are affected by transboundary pollution. If the transboundary air masses originated from the Eastern European areas, the concentration as well as the oxidative capacity of fine particles was significantly higher in urban background air in Tartu compared to air masses coming from Scandinavian areas (Paper I). During the last 15 years, traffic increase has been very fast in Tartu. However, due to the improvement in vehicle technology during this period, there has been only a slight increase in concentration of exhaust particles (Paper II). Nevertheless, a greater increase in road dust emissions was detected. A statistically significant relationship between long-term exposure to those traffic induced par­tic­les and cardiac disease in the RHINE (Respiratory Health in Northern Europe) Tartu cohort was shown (Paper III). However, no significant associations with respira­tory health were found. The HIA in Tallinn demonstrated 296 (95% CI = 76–528) premature deaths annually, because of PM (Paper IV). The average decrease in life expectancy was predicted to be 0.64 (95% CI 0.17–1.10) years. However, among risk groups it can be higher. In addi­tion, several cardiovascular hospitalizations are related. The costs to society be­cause of health effects reach up to €150 million annually (95% CI = 40–260) from pre­mature deaths and hospitali­zation constitute an additional €0.3 million (95% CI = 0.2–0.4). The special HIA scenario, when more pollution fuel peat will be used in boiler houses was analysed as well (Paper V). It indicated that peat bur­ning would result in up to 55.5 YLL per year within the population of Tartu. However, the health effects of pollution from current traffic, local heating, and industry are at least 28 times bigger. In conclusion, exposure to PM cause considerable health effects in the form of cardio­pulmo­nary diseases in main Estonian cities.
45

The economics of happiness : linkages between microfinance, happiness, and wellbeing in rural Thailand

Bunsit, Thanawit January 2016 (has links)
The idea of microfinance has burst into the area of global poverty reduction. Many comments have been made about its benefits such as; it is an alternative tool for poverty alleviation and sustainable development. Many studies have attempted to assess different facets of the impact of microfinance, especially trying to show its potential for greater financial inclusion and economic benefits using advanced rigorous quantitative approaches. Although some studies have evaluated this topic in the past there remains some significant gaps in the literature, including the impact of microfinance on other dimensions such as the social impact, education or environmental impact, the impact on happiness and subjective wellbeing of its clients has been hardly examined. This study aims to fill this gap by using rigorous quantitative methods with a rich qualitative dataset to assess the impact of microfinance on both economic and non-economic aspects, especially the happiness and psychological dimension. I Use primary data from a household survey and an ethnographic approach combining quantitative methods such as matching estimators, propensity score matching with nonparametric regression. The mixed methods were employed in order to evaluate the impact of the microfinance schemes on the improvement of borrowers’ wellbeing, household condition and local economic and environmental development. The most notable findings were that the borrowers from the savings group using group lending schemes utilised the loan for mainly entrepreneurial purposes and household spending, performed better than other groups of borrowers. This could be seen from the increase in household income and a high repayment rate. In addition, by observing the social impacts, it indicated that the group lending together with the ecotourism project generated and strengthened the social ties in the community. The group members also produced high positive psychological indicators compared to the non-member households. Easterlin’s paradox was revisited and found that not only was it income that affected happiness and wellbeing, but other factors seemed to have an influence on self-reported happiness. Those factors included health or health condition of family members which significantly influenced self-reported happiness in all models. Considering the impact of microfinance on happiness and wellbeing, it was found that clients of the group lending scheme can repay better and led to a higher level of self-reported happiness and subjective wellbeing. The ability to repay also affected a low level of stress or negative moods.
46

Carbon cycling in the York River Estuary: an isotopic and mass balance approach using natural Carbon-14 and Carbon-18 isotopes

Linebaugh, Donald W. 01 January 1999 (has links)
No description available.
47

Are We Providing Preferred Floral Resources for Bees in Our Neighborhoods?: Assessing the Relationship Between Small Scale Vegetation Metrics and Bee Presence in SE Portland

Wallace, Hailey 12 July 2019 (has links)
Bee pollinators can thrive in highly urbanized environments if their preferred floral resources and habitat types are available. Enhanced pollinator habitats are being created globally, with a large local effort in Portland, Oregon. This project determined if we were providing the most preferred floral resources at enhanced pollinator sites for bees, if floral resources were available throughout the season, and if differences in dietary preferences between native and honey bees would allow for the identification of "native bee floral resources" in South East Portland. Bee pollinators were monitored from June to August at three enhanced pollinator sites in South East Portland, Oregon. A total of 566 individual bees were observed, tiny dark bees and bumblebees composed the large majority of the urban bee composition. Vegetation metrics and bee presence were correlated using a Generalized Linear Mixed Model and significant variables that predicted bee presence included Solidago canadenisis (p-value 0.0024), density of floral resources (p-value
48

Seasonal Variations in Fish Assemblages of Small Warmwater Streams in Four Southeastern National Parks

Zimmerman, Joseph Carl 01 May 2007 (has links)
Small warm-water streams in the southeastern United States experience significant differences in temperature, as well as changes in physical parameters due to seasonal fluctuations. It has been generally thought that fish assemblage patterns change as a direct result of these seasonal variations. This study was designed to determine the effects of variable flow regimes on fish species composition, diversity, and abundance. Eight small warm-water streams in four national parks (Chickamauga and Chattanooga National Military Park, Fort Donelson National Battlefield, Abraham Lincoln Birthplace National Historic Site, and Russell Cave National Monument) were sampled May-June 2005 for the summer trials, October-November 2005 for the fall trials, and April 2006 for the spring trials. All trials were conducted when water levels and flows were at normal seasonal stages. Fish populations were determined by electrofishing a 100-m reach at each site. Physical parameters including temperature, dissolved oxygen, conductivity, pH, and flow rate were also measured at each site. From summer to fall, the majority of the streams decreased in flow until temporary pools were formed. The lack of flow caused increased temperatures, decreased dissolved oxygen, and increased conductivity levels. As a direct result, overall fish abundance and diversity values decreased. From fall to spring, all the streams increased in flow, which brought back the riffle to pool habitat sequences. Dissolved oxygen levels increased, conductivity levels decreased, and temperatures became more stable. As a result, overall fish abundance and diversity values increased. Results indicated that fish assemblage patterns in the four parks did change as a direct result of the seasonal variations in habitat and water quality.
49

Integrating strategic environmental assessment and cumulative effects assessment in Canada

Harriman Gunn, Jill 29 June 2009
In Canada, interest in regional strategic environmental assessment as a framework for assessing cumulative environmental effects is growing. Strategic environmental assessment, and in particular regional strategic environmental assessment, is generally regarded as the preferred assessment framework within which to address cumulative effects due to its broad scale of assessment and its focus on influencing future development. However, very little research has been done to confront the challenges, either conceptually or methodologically, in operationalizing strategic environmental assessment at a regional scale and in assessing cumulative environmental effects in this regional and strategic context. This dissertation advances work in this area by defining a conceptual framework and generic methodology for regional strategic environmental assessment that deliberately integrates cumulative effects considerations.<p> The research methodology includes a literature review, framework and case reviews, and three sets of interviews with Canadian and international practitioners, academics, and administrators knowledgeable on strategic environmental assessment and cumulative effects assessment issues. The research results are reported in four manuscripts. The first manuscript presents a typology of current approaches to regional cumulative effects assessment. The second manuscript reviews lessons from recent attempts at regional-scale, strategically-focused environmental analysis in Canada that include an impact assessment component and explicit attention to cumulative environmental effects. The third manuscript presents a structured framework for regional strategic environmental assessment in Canada, and the fourth manuscript discusses conceptual and methodological challenges that accompany the integration of strategic environmental assessment and cumulative effects assessment.<p> Significant findings include that cumulative effects assessment does indeed represent a significant conceptual and methodological challenge in a strategic assessment context and that cumulative effects assessment in this context requires more than simply adding up direct effects. Further, this research indicates that the seminal contribution of regional strategic environmental assessment is to determine the pace and nature of future development in a region, including significant regional environmental thresholds, targets, and limits; and to inform decision makers of the broader, the slower-moving, the farther-reaching, and perhaps the more insidious currents of environmental change. Moving forward, there is a need to further develop and demonstrate approaches to cumulative effects assessment in a strategic context, develop a supportive legislative and regulatory framework for regional strategic environmental assessment in Canada, and define the unique contribution of regional strategic assessment in relation to regional planning and management.
50

Advances in life cycle impact assessment of pesticides: methodological improvements and experimental studies

Juraske, Ronnie 27 September 2007 (has links)
El objetivo principal de esta tesis doctoral es el de contribuir al desarollo y evaluación en la aplicación y exposición de pesticidas en plantas y su impacto sobre la salud humana y los ecosistemas. Los modelos ambientales usados para la evaluación de impacto en el análisis de ciclo de vida y en analisis de riesgo ambiental relacionan las emisiones con su impacto, combinando el destino y la exposición estimada y relacionandolo con información toxicológica. Los pesticidas liberados en aire, agua y suelos llegan al cuerpo humano a través de los alimentos, principalmente por la ingestión de las partes comestibles de los vegetales. Por dicha razón, es de gran importacia el desarollo de métodos para el análisis de residuos tóxicos en productos agrícolas. De aquí emergen las siguientes preguntas:1. ¿Como puede ser modelada la cantidad residual y el lugar de destino de los pesticidas aplicados por aire en los invernaderos? ¿Cual es su compotamiento dinámico y como afecta la concentración residual en las partes comestibles de los vegetales?2. ¿Como puede medirse y modelarse la degradación de los pesticidas tanto en superficie como en el interior de vegetación?3. ¿Como puede hacerse una estimación de la vida media específica tanto en superficie como en el interior de vegetales partiendo de la información de degradación en el suelo?4. ¿Como puede desarollarse un indicador de riesgo con el cual se puedan analizar comparativamente pesticidas basado en el lugar de aplicación, tiempo de exposición y características toxicológicas?Después de una breve introdución al análisis medioambiental y los problemas específicamente relacionados con la aplicación de pesticidas y sus características en el capítulo uno, en el capítulo dos se propone un acercamiento a través del modelado de residuos de pesticidas en tomates cultivados en invernadero. Este modelo de destino y exposición tiene en consideración el tiempo transcurrido entre la aplicación, la cosecha y el consumo, la absorción del spray depositado en la superficie de las plantas, las propiedades de transporte a través de la cutícula, la degradación en el interior de la misma planta y perdidas debido al procesado del alimento. El modelo fue validado usando datos experimentales obtenidos a partir de ensayos de campo. También se presenta la fracción de pesticida ingerido por humanos debido al consumo de tomate mostrando un escenario realista de la exposición humana a estos productos.En el capítulo tercero se presentan dos algoritmos genéricos para la estimación de (i) la vida media específica de pesticidas en superficie y (ii) en el interior de las plantas, usados en el modelo de destino y exposición. También se propone una rutina de extrapolación para estimar la vida media de plaguicidas en superficie, basándose en un factor de conversión cuya base de cálculo parte de la vida media de estos en suelos. Más adelante se presenta un método de estimación tentativa para el cálculo de la vida media de pesticidas en el interior de las plantas, básandose en datos experimentales.El capítulo cuatro es una prolongación de los capítulos dos y tres. Los resultados antes obtenidos, se combinan aquí con un nuevo método de análisis experimental para medir absorción, transporte y persistencia de pesticidas en tomates tratados por (i) spray foliar estándar y (ii) aplicación en raíces por riego por goteo. Un modelo dinámico de absorción de pesticidas por raíz trata de estimar la dependencia temporal de la concentración del contaminante en los frutos. Finalmente, los resultados experimentales son comparados con el modelo en terminos de ingestión de fracción de pesticida por parte de la población humana. En esta investigación se intenta evaluar el comportamiento medioambiental de los pesticidas comparando los diferentes métodos de aplicación de un mismo ingrediente activo.El capítulo cinco ilustra el desarollo de un nuevo método llamado PestScreen, el cual calcula el nivel relativo de riesgo de pesticidas con el fin de clasificarlos ascendentemente dependiendo de su impacto. Esta aproximación es un método de estimación del nivel relativo de riesgo y permite comparar la peligrosidad tanto a nivel de salud humana como de impacto medioambiental, de diferentes tipos de pesticidas, a través de una categorización. Este método se desarolla como una herramienta para la evaluación e identificación de pesticidas con peligrosidad medioambiental usados en la agricultura. PestScreen incorpora tanto su efecto tóxico como su destino y exposición en varios compartimentos medioambientales. Esto se realiza combinando medidas de toxicidad química con la cantidad liberada, la persistencia medioambiental, el potencial de transporte en un radio amplio y la fracción ingerida por la población humana. En el capítulo seis los principales resultados son presentados y resumidos, finalmente se sugieren recomendaciones para investigaciones futuras. / The overall goal of this dissertation is to contribute to the development of best available practice in fate and the exposure assessment of pesticides for evaluating their impacts on human health and ecosystems. Environmental models used in Life Cycle Impact Assessment (LCIA) and Environmental Risk Assessment (ERA) relate emissions to impacts by combining fate and exposure estimates with toxicological assessment data. Pesticides released to air, water, soil and plants enter the human body through food commodities, particularly through the ingestion of arable parts of plants. Therefore, specific methods to assess the presence of residues in agricultural products are of importance for human exposure assessment. This raises the following questions:1. How can the fate (from air and soil) of pesticides in/on plants cultivated in greenhouses be measured and modelled? How does dynamic behaviour affect the final residues in arable parts of plants?2. How can the degradation of pesticides on plant surfaces and within plants be measured and modelled? 3. How can a substance specific half-life in/on plants be estimated from soil degradation data using extrapolation routines?4. How can a risk indicator for comparative assessment of pesticides be developed using fate, exposure, and toxicity characteristics?After a short introduction to environmental assessment approaches and the specific problems related to the application of pesticides and their characteristics in Chapter 1, Chapter 2 proposes an approach for modelling pesticide residues in greenhouse tomato plants. This fate and exposure model considers the time between pesticide application and harvest, the time between harvest and consumption, the absorption of spray deposit on plant surfaces, transfer properties through the cuticle, degradation inside the plant and loss due to food processing. The model is validated with experimental data which was obtained from field trials conducted in the Catalan Institute for Food and Agricultural Research and Technology (Institut de Recerca i Tecnologia Agroalimentàries; IRTA) in Cabrils (Barcelona). Human intake fractions of pesticides due to ingestion of tomatoes representing a realistic scenario of human exposure to pesticide residues in foods are presented.In Chapter 3, two generic estimation routines for substance specific half-lives of pesticides (i) on plant surfaces and (ii) within plants to be used in fate and exposure models are presented. First, an extrapolation routine for the estimation of pesticide half-lives on plant surfaces based on a conversion factor from half-lives of pesticides in soil is proposed. Furthermore, a tentative estimation method for the calculation of metabolism half-lives of pesticides in inner parts of plants based on experimental data is presented.Chapter 4 presents a follow-up of Chapter 2 and Chapter 3. Previous results are combined with new experimental assessment to measure the uptake, translocation and persistence behaviour of pesticides in tomato fruits treated by (i) standard foliar spray application and (ii) soil application using direct localised drip irrigation into root zone. A dynamic root uptake model for pesticides aiming at the estimation of time dependent contaminant concentrations in fruits is proposed. Finally, experimental results are compared with model estimates in terms of human population intake fractions of pesticides. These investigations aim to evaluate the environmental performance of pesticides when the same active ingredient is applied to crops by different application techniques. Chapter 5 illustrates the development of a new method entitled PestScreen, to calculate the relative risk level of pesticides with the aim of ranking them from lowest to highest degree of concern. The approach is an estimation method of relative risk levels and allows comparing environmental and human health risks of specific pesticide types through their ranking. The method is developed to serve as an analytical tool in screening and identification of pesticides of environmental concern used in agriculture. PestScreen incorporates both the toxic effects of pesticides and their fate and exposure characteristics in different compartments of the environment. This is done by combining measures of chemical toxicity pertaining to both human health and the environment with chemical release amounts and information on overall environmental persistence, long-range transport potential and human population intake fractions. In Chapter 6 the most important results are summarized and recommendations for further research are discussed.

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