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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.
31

Application of the Relevance Vector Machine to Canal Flow Prediction in the Sevier River Basin

Flake, John T. 01 May 2007 (has links)
This work addresses management of the scarce water resource for irrigation in arid regions where significant delays between the time of order and the time of delivery present major difficulties. Motivated by improvements to water management that will be facilitated by an ability to predict water demand, this work employs a data-driven approach to developing canal flow prediction models using the Relevance Vector Machine (RVM), a probabilistic kernel-based learning machine. Beyond the RVM learning process, which establishes the set of relevant vectors from the training data, a search is performed across model attributes including input set, kernel scale parameter, and model update scheme for models providing superior prediction capability. Models are developed for two canals in the Sevier River Basin of southern Utah for prediction horizons of up to five days. Appendices provide the RVM derivation in detail.
32

Salinity Management in the Upper Colorado River Basin: Modeling, Monitoring, and Cost-Equity Challenges

Keum, Jongho 01 May 2014 (has links)
Salinity issues in the Upper Colorado River Basin have been a serious concern to the western United States and northern Mexico. The Colorado River salinity is mainly come from geologic materials located in the Upper Colorado River Basin. Natural weathering and human activities, such as irrigation, accelerate the dissolution of saline materials. Economic damages due to salinity in the Colorado River Basin are estimated at $295 million in 2010, for example, reduced crop yield, plugging of water pipes and fixtures, and ecological health of rivers. In order to manage salinity in the Upper Colorado River Basin, SPARROW model has been applied to simulate salinity sources and transport. However, the model application discontinued during recent past due to lack of data. Given the motivation and importance of salinity issues in the Colorado River Basin, the overall goal of this research is to develop a decision-making framework for an effective salinity management in the Upper Colorado River Basin. First, this research introduced a methodology for reliable analysis of salinity sources and transport in the Upper Colorado River Basin. However, recent decreasing trend of number of monitoring stations may cause increase of model uncertainty. Therefore, a decision-making methodology for an effective water quality monitoring network was developed. From the results of monitoring network analysis, the redundancy or scarcity of monitoring stations in each watershed can be identified under the given operational costs. Finally, salinity management scenarios considering cost and equity were developed. Management options considering cost only can neglect the fairness in the allocation of salinity control responsibilities among stakeholders. To overcome this limitation in management, the methodology developed in this research considers cost of salinity control, equitable distributions among stakeholders, and cost efficiency. The methodologies developed in this research provide a comprehensive decision-making framework for an effective salinity management in the Upper Colorado River Basin. Moreover, this framework is not limited to the management of salinity in the Upper Colorado River only, but also can be applied to other water quality management problems.
33

Asbestos pollution in the Rivière Nicolet Basin near Asbestos, Quebec

Wright, Richard Kyle January 1976 (has links)
No description available.
34

Environmental Sustainability of Water Projects

Tortajada, Cecilia January 2001 (has links)
The thesis focuses on the environmental sustainability ofwater projects. The concept is analysed from the theoreticaland the implementation viewpoints The evolution of the conceptof sustainable development is presented, with an in-depthdiscussion on the present status of the environmentalsustainability of water projects. Several case studies areanalysed on different important aspects of environmentalsustainability. These case studies include the analysis ofissues like the role of institutions, effectiveness of legalframeworks, participation of stakeholders, contributions ofwater development projects to regional development,consideration of environmental and social issues, and impactsof social and environmental movements. The impacts of the Ataturk dam, within the SoutheasternAnatolia (GAP) Project, Turkey, are analysed in terms ofplanning, policy making, institutional arrangements,infrastructural development, and human resources development.Its economic, social and environmental impacts during theconstruction phase and the first seven years of operation arereviewed. The role of large dams in poverty alleviation andsocio-economic development are analysed, especially in terms ofresettlement. The current global thinking on involuntaryresettlement is reviewed, as are the experiences onresettlement of the people affected by water projects. Anassessment of the participatory process that was formulated forthe resettlement of the people affected by the construction ofthe Birecik dam, GAP Project, Turkey, is presented. Institutional arrangements for integrated river basinmanagement in Latin America is analysed, with special emphasison the Brazilian and the Mexican experiences of watermanagement at the river basin level. Brazil and Mexico werechosen since they are by far the most advanced in this area,compared to all the other Latin American countries. It is concluded that economic, social and environmentaldimensions should be considered concurrently within the goalsof water development. Social considerations are essentialbecause poverty is both a cause and an effect of environmentaldegradation, and societies festering with poverty and socialtensions will not have the means, or inclination, to makesustainable development a priority issue. There are noblueprints for a transition to sustainability, but there arepolicy reforms that could reduce environmental degradation,income disparity and persistent poverty. The water sector isnot an exception to this conclusion. There is now considerable discussion on the operationalfeasibility of the sustainable development concept. It issuggested that sustainable development should be considered tobe a journey and not a destination. The world is nothomogeneous, and thus there cannot be one unique path tosustainable development that would be equally valid andapplicable for all countries of the world, and for alldevelopment sectors. Each country will have to base its waterdevelopment agendas depending on their own social, economic,cultural and environmental conditions, available managerial,technical and administrative capacities and societalexpectations and aspirations. For developing countries, as longas water development policies, programmes and projects cancontribute to socio-economic development, reduction in povertyand income disparity, and environmental conservation, they arewell on course in their long journey to sustainabledevelopment. Definitional debates as to what constitutessustainable water development are likely to beunproductive.
35

Risk Perception and Communication : A Study on How People Living in the Tisza River Basin, Hungary Perceive the Risk of Floods and How the Flood Risk Communication Between Authorities and the Public Could Be Improved

Svahn, Christer January 2013 (has links)
It has been stressed within social sciences that risk management has focused too much on technical solutions and in order to decrease the risks also social factors have to be taken into account, namely the way people perceive risk. Risk perception is an important research field working on these issues. The aim of the study was in the light of the diverging views between the two paradigms to understand which of the psychometric or the cultural theory paradigm that can to a larger extent explain the flood risk perception of people living in the Tisza River basin. Furthermore the aim was to understand how the gap between experts’ and the public’s view on flood risk communication can be understood as well as how the risk communication could be improved. Data was collected through a survey and interviews. The results show that risk perception can partly be explained by either paradigm. To better understand people’s risk perception studies need to be more empirically based, not treat people’s perception as something too abstract and understand the interaction between individuals, society and the environment. The gap between the public’s and experts’ views is not as large as expected. In order to improve flood risk communication, decision makers need a better understanding of citizens’ perceptions and the motivation to include public perception in flood risk management need to be based on the view that the public could have an important input into risk management.
36

Environmental Sustainability of Water Projects

Tortajada, Cecilia January 2001 (has links)
<p>The thesis focuses on the environmental sustainability ofwater projects. The concept is analysed from the theoreticaland the implementation viewpoints The evolution of the conceptof sustainable development is presented, with an in-depthdiscussion on the present status of the environmentalsustainability of water projects. Several case studies areanalysed on different important aspects of environmentalsustainability. These case studies include the analysis ofissues like the role of institutions, effectiveness of legalframeworks, participation of stakeholders, contributions ofwater development projects to regional development,consideration of environmental and social issues, and impactsof social and environmental movements.</p><p>The impacts of the Ataturk dam, within the SoutheasternAnatolia (GAP) Project, Turkey, are analysed in terms ofplanning, policy making, institutional arrangements,infrastructural development, and human resources development.Its economic, social and environmental impacts during theconstruction phase and the first seven years of operation arereviewed.</p><p>The role of large dams in poverty alleviation andsocio-economic development are analysed, especially in terms ofresettlement. The current global thinking on involuntaryresettlement is reviewed, as are the experiences onresettlement of the people affected by water projects. Anassessment of the participatory process that was formulated forthe resettlement of the people affected by the construction ofthe Birecik dam, GAP Project, Turkey, is presented.</p><p>Institutional arrangements for integrated river basinmanagement in Latin America is analysed, with special emphasison the Brazilian and the Mexican experiences of watermanagement at the river basin level. Brazil and Mexico werechosen since they are by far the most advanced in this area,compared to all the other Latin American countries.</p><p>It is concluded that economic, social and environmentaldimensions should be considered concurrently within the goalsof water development. Social considerations are essentialbecause poverty is both a cause and an effect of environmentaldegradation, and societies festering with poverty and socialtensions will not have the means, or inclination, to makesustainable development a priority issue. There are noblueprints for a transition to sustainability, but there arepolicy reforms that could reduce environmental degradation,income disparity and persistent poverty. The water sector isnot an exception to this conclusion.</p><p>There is now considerable discussion on the operationalfeasibility of the sustainable development concept. It issuggested that sustainable development should be considered tobe a journey and not a destination. The world is nothomogeneous, and thus there cannot be one unique path tosustainable development that would be equally valid andapplicable for all countries of the world, and for alldevelopment sectors. Each country will have to base its waterdevelopment agendas depending on their own social, economic,cultural and environmental conditions, available managerial,technical and administrative capacities and societalexpectations and aspirations. For developing countries, as longas water development policies, programmes and projects cancontribute to socio-economic development, reduction in povertyand income disparity, and environmental conservation, they arewell on course in their long journey to sustainabledevelopment. Definitional debates as to what constitutessustainable water development are likely to beunproductive.</p>
37

The Influence of Groundwater Flowpaths, Nutrients, and Redox Conditions on the Extent of Microbial Methanogenesis in Coal Beds Using Solute and Isotope Chemistry: Powder River Basin, USA

Bates, Brittney Lynette January 2010 (has links)
Water and gas samples were collected from coalbed methane wells and surface coal mines in the Powder River Basin and analyzed for solute chemistry, isotopes, and gas composition to determine timing and source of recharge, nutrient influxes, extent of methanogenesis, and redox conditions. Delta18O-H2O values and hydraulic gradients show recharge to coal beds is principally from the southern basin margin with inputs from the western and eastern margins. Detectable 14C in coal waters indicates they were recharged <50,000 BP. Correlation of deltaD-CH4 and deltaD-H2O values suggests that methane has accumulated since the Late Pleistocene. Nutrient concentrations were low and did not correlate to groundwater recharge sources. Coal gases from the northwestern basin are isotopically-depleted suggesting 'early stage' methanogenesis, whereas coal gases from the central southeastern basin are isotopically-enriched suggesting 'late stage' methanogenesis. Several wells have elevated SO4 and oxygen, which may be due to recent hydrologic changes from groundwater pumping.
38

The discrimination of cottonwood clones in a mature population along the Oldman River, Alberta

Gom, Lori A., University of Lethbridge. Faculty of Arts and Science January 1996 (has links)
In the northwestern prairies, the cottonwoods Populus deltoides Batr., P. balsamifera L., P. angustifolia James, and inerspecific hybrids, form the foundation of the riparian forest ecosystem. The present project characterized the phenotype and 391henology of each tree in a mature cottonwood grove (N=391) for the purposes of clone-delineation. In order of their utility, tree sex, general leaf-shape, six leaf dimensions, and phenology of flowering, leaf-flushing, senescence,and leaf-abscission were utilized. The population's 391 trunks represented only 115 individuals, 67 of which were clones which ranged from 2 to 58 trunks each. Thus, 88% of all trunks belonged to clones which ranged from 2 to 58 trunks each. Thus, 88% of all trunks belonged to clones, and this high clonal content reflects the senior age of the population. Clone structure explained the population's apparent spatial-clumping, female-skewed sex ratio, differential spatial distributions of the sexes and species, and complexity in trunk-size classes. Trends suggest that P. balsamifera and P. angustifolia are more strongly clonal than P. deltoides, partially explaining their differences in environmental preferences. The observed extent of asexual regeneration has implications for riparian resource management and analyses of cottonwood reproductive ecology. / xv, 201 leaves : ill. ; 28 cm.
39

Modelling the potential impacts of climate change on snowpack in the St. Mary River watershed, Montana

MacDonald, Ryan J, University of Lethbridge. Faculty of Arts and Science January 2008 (has links)
Climate change poses significant threats to mountain ecosystems in North America (Barnett et al., 2005) and will subsequently impact water supply for human and ecosystem use. To assess these threats, we must have an understanding of the local variability in hydrometeorological conditions over the mountains. This thesis describes the continued development and application of a fine scale spatial hydrometeorological model, GENESYS (GENerate Earth SYstems Science input). The GENESYS model successfully simulated daily snowpack values for a 10 year trial period and annual runoff volumes for a thirty year period. Based on the results of these simulations the model was applied to estimate potential changes in snowpack over the St. Mary River watershed, Montana. GCM derived future climate scenarios were applied, representing a range of emissions controls and applied to perturb the 1961-90 climate record using the “delta” downscaling technique. The effects of these changes in climate were assessed for thirty year time slices centered on 2020s, 2050s, and 2080s. The GENESYS simulations of future climate showed that mountain snowpack was highly vulnerable to changes in temperature and to a lesser degree precipitation. A seasonal shift to an earlier onset of spring melt and an increase in the ratio of rain to snow occurred under all climate change scenarios. Results of mean and maximum snowpack were more variable and appeared to be highly dependent on scenario selection. The results demonstrated that although annual volume of available water from snowpack may increase, the seasonal distribution of available water may be significantly altered. / viii, 93 leaves ; 29 cm
40

Response of riparian cottonwoods to experimental flows along the lower Bridge River, British Columbia

Hall, Alexis Anne, University of Lethbridge. Faculty of Arts and Science January 2007 (has links)
The Bridge River drains the east slope of the Coast Mountain Range and is a major tributary of the Fraser River in southwestern British Columbia. The lower Bridge River has been regulated since the installation of Terzaghi Dam in 1948, which left a section of dry riverbed for an interval of 52 years prior to 2000. An out-of-court settlement between BC Hydro and Federal and Provincial Fisheries regulatory agencies resulted in the required experimental discharge of 3 m3/s below Terzaghi Dam in 2000. This study investigated growth of black cottonwood (Populus trichocarpa) trees in response to the experimental discharges. Mature trees did not show a significant response in radial trunk growth or branch elongation. In contrast, the juvenile trees displayed an increased growth response, and the successful establishment of saplings provided a dramatic response to the new flow regime. Thus, I conclude that cottonwoods have benefited from the experimental flow regime of the lower Bridge River. / xii, 89 leaves : ill. (some col.) ; 29 cm

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