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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.
81

A Combined Field And Laboratory Investigation Into The Transport Of Fecal Indicator Microorganisms Through A Shallow Drinking Water Aquifer In Bangladesh

Feighery, John E. January 2013 (has links)
This dissertation presents an examination of the causes and mechanisms underlying the widespread contamination of a shallow groundwater aquifer by fecal bacteria. The context for this study is a field site located in a rural area of Bangladesh that represents a microcosm for the many challenges facing the approximately 2 billion people worldwide who rely upon groundwater for their daily needs. The unique contributions of this work include an improved numerical model for fitting column test results, a conceptual model to explain seasonal patterns of well contamination based on the hydraulic interaction of ponds and irrigation/drainage canals and a new understanding of the important role that such canals might play in predicting the microbial contamination of shallow aquifers in flood-protected areas. The mechanisms responsible for filtration of the fecal indicator bacteria, Escherichia coli, during passage through the fine sand aquifer were first investigated through laboratory column experiments using intact sediment cores from the field site as well as repacked sediment that had been dried and, in some experiments, chemically cleaned. To fit the hyper-exponential spatial profiles of attached bacteria in one third of the experiments, a finite difference two-population model with reversible and irreversible attachment modes incorporating bacterial die-off was developed. Where the two-population phenomenon was observed, one population typically was highly irreversible while the other was reversible with a smaller irreversible attachment rate. When applied to transport in the field, this model predicted only a two-fold reduction in bacterial concentrations over a distance of 10 m and transport was limited mainly by the bacterial die-off rate, which was also measured using microcosm experiments. The occurrence of the second population was associated with larger grain size and lower percentage of fine particles and the attachment rates in general increased linearly with increasing percentage of fines. Transport from contaminated surface water to nearby tubewells was studied in the field through measurements of bacterial infiltration below canals and ponds both inside and outside of the flood control embankment. A two-dimensional finite element model of the field-pond-canal system was built and fitted to heads measured at three monitoring wells and 2 surface water bodies. Using parameters from the field measurements, the model was not able to explain the seasonal pattern of E. coli concentrations in tubewells, even when reversible attachment assumptions from the column test results were applied. An alternative conceptual model that incorporates the seasonal shift in flow direction caused by the canal network was developed using the fitted finite element model and could explain the observed pattern of well contamination. The importance of the irrigation/drainage canals in determining the frequency of tubewell contamination by E. coli at the site was further demonstrated by applying a logistic regression model using the intensity of latrines, canals and ponds as predictors, after applying spatial decay rates drawn from the infiltration literature. The resulting Intensity Model found that population density, unsanitary latrines and canals together could explain 48% of the variation in the frequency of E. coli detection in tubewells, but these parameters were only significant at a low spatial decay rate (0.01 m-1). A less complex Proximity Model provides nearly the same explanatory power but only required population with 25 m and the distance to the nearest canal as predictors. These models could be useful in predicting water-related health risks, evaluating contamination risk for groundwater sources based on the sanitary environment around the well or estimating the potential benefits from improvements to sanitation infrastructure in a given region.
82

The Two Rivers: Water, Development and Politics in the Tigris-Euphrates Basin, 1920-1975

Stahl, Dale January 2014 (has links)
At the end of the First World War, new states were created in the former domains of the Ottoman Empire. In the region between the Tigris and Euphrates Rivers, Britain and France obtained through conquest and international writ new "mandate" territories in Iraq and Syria, while in 1923 a new Turkish republic was founded on the Anatolian peninsula. During the next two decades, governments in these states planned a series of water control projects on the two rivers as part of broad economic development efforts. Many of these projects were eventually constructed after the Second World War, shaping the environment of the river basin with dams, flood control and irrigation works, and hydroelectric power stations. By comparing these states' efforts to exploit natural resources and manage the environment of the basin, this study considers the environmental function in the shift from empire to independent nation-state and in the diverse processes of modern state formation. Through water resource exploitation, Iraq, Syria and Turkey founded modern bureaucracies, centralized control over natural resources, and justified new techniques to manage populations. However, the intentions of Baghdad, Ankara and Damascus, as well as the results obtained, differed in significant ways, providing insight not only into the nature of these states, but also the political dimensions of managing a critical natural resource. This dissertation is based on analysis of archival records in Arabic, English, French and Turkish, collected from institutions in England, France, the United States, India and Turkey.
83

Water security mercantilism? : transnational state-capital alliances & multi-level hydropolitics of land-water investments in Egypt and the Nile Basin

Hanna, Ramy W. Lofty January 2019 (has links)
Conventionally, the question of Egyptian water security focused on state-centric transboundary hydropolitics within the larger context of the Nile basin. The presented research explores 'water security' beyond this 'state-centric epistemology', typically focusing on a singular scale of hydropolitical analysis. This dissertation examines the water (hydro) politics of transnational land-water investments (LWI) within Egypt and the larger context of the Nile river basin. Adopting a multi-site case study methodology, it critically examines the changing role of the state and the engagement of non-state actors in the silent appropriation of land-water resources through investments in farmlands abroad. The research methodology contextualizes how land acquisitions take several shapes and forms within Egypt (Old-New Lands and New Lands/Mega Projects), as well as in other Nile basin countries (e.g. Sudan). They also manifest land-water-food nexus interdependencies for both; profit and larger strategic objectives, through the formation of 'State-Capital alliances'. Deploying a case study of an international Emirati investor in Egypt, it shows how land-water investments are rooted in a larger socio-political project as part of the state's vision of horizontal expansion and land reclamation, to address its ecological-demographic narrative of crisis. The research also draws linkages between Egyptian water security and transnational investments in other Nile basin countries with a particular focus on the case of Sudan as part of its larger vision of the 'breadbasket of the Arab World'. However, while these State-Capital alliances are rooted in narratives of state modernization, security, and profit, they entail various tensions and trade-offs amongst different resources nexi and actors, thus masking larger questions of social justice and equity. These tensions often reflect the manufacture of abundance and translate into water grabs transcending multiple hydropolitical scales. The thesis argues that the changing role of the "entrepreneurial state" and the engagement of non-state actors in transnational land-water investments manifest a transition from the hydraulic mission towards water security mercantilism. I argue that "water security mercantilism" denotes water grabbing, which overrides the conventional understanding of the hydraulic mission (water control by the state); towards a broader understanding of the role of non-state actors and international investors in accessing water, thus creating their own private resources security nexus. Hence, drawing on development studies, hydropolitics, and political economy scholarship, this dissertation broadens out the analysis of Egyptian water security beyond singular-scale state-centric hydropolitical debates; towards a multi-level polycentric analysis of water security, central to which are the farmers, the investors, and the state itself. This implies that transnational land-water investments not only influence small farmers through the reproduction of scarcity on the local level, but also influence the hydraulic mission of the state on the national level, and the larger Nile basin transboundary hydropolitics.
84

Optimal expansion of a water resource system and issues of water allocation and utilization : Umatilla River Basin, Oregon

Lin, Biing-Hwan 05 September 1980 (has links)
In the past decade considerable research in several disciplines has been oriented toward the design of optimal capacity expansion plans for water resource systems. The emphasis of most of these efforts has been directed toward minimization total cost outlays in project planning. This focus somewhat limits the full applicability of the optimal capacity expansion solutions since it is believed that the criteria of economic efficiency is not well addressed in this mode. This study explores the merits of scheduling water resource project facilities on the basis of anticipated economic benefits provided, an approach needed only infrequently in the systems engineering literature. Using the Umatilla River Basin in Northeast Oregon as a case study example, the facilities (and their alternatives) of a previously planned federal water resource development project in that area were carefully analyzed with respect to the magnitude and timing of anticipated benefits and costs. Irrigated agriculture and fishery development/enhancement benefits were the two principal purposes of the project considered. In addition, benefits arising from flood prevention, municipal and industrial water supply, and erosion control were also integral to the original overall evaluation. The design of the research was to first implement a basic scheduling model in the context of the case study area and then to explore the ramifications of exchange-theoretic and distribution-theoretic criteria on the timing of facilities and the ultimate allocation of water among purposes. The model implemented was aimed at maximizing the present value of net benefits inherent in an optimally timed set of facilities subject to an annual budget constraint. Having designed the model along integer programming lines, three different solution techniques were explored in order to realize a desirable level of efficiency in basic model solution. It was found that reasonably efficient solutions could be obtained. By optimally timing the facilities it was found that the total present value of net benefits of the project could be significantly enhanced when compared to the original schedule proposed in the project planning documents. Of even greater interest is the issue of incorporating into the planning process (and specifically into the capacity expansion mode of planning) considerations of tradeoffs or exchanges between project beneficiaries. Such exchanges and other distributional criteria can affect and be affected by the selection and timing of project facilities within an overall project design. These interrelationships are explored paying particular attention to the way in which exchanges of water (via water rights transfers) could establish higher levels of benefits in future years. Noneconomic exchange processes such as the enforcement of extant property rights relating to water resources are another issue which complicated the process of water planning. Such distributional criteria are difficult to incorporate into the capacity expansion mode of planning analysis. However, ways are explored by which the basic model may be modified and used by decision makers in order to take account of more realistic problems in water resource planning for individual river basins. / Graduation date: 1981 / Partially funded by the U.S. Dept. of the Interior as authorized under the Water Research and Development Act of 1978. / Final technical completion report for project no. A-046-ORE to U.S. Dept. of the Interior.
85

Effects of reservoir recreation development upon rural residential property values /

Boodt, William Allan. January 1978 (has links)
"A thesis submitted to Oregon State University." / Includes appendices. Photocopy of original. Includes bibliographical references (leaves 126-132). Also available on the World Wide Web.
86

SEASONAL SNOW SURFACE ENERGY BALANCE AT THE CENTRAL SIERRA SNOW LABORATORY

Halverson, Howard Gene, 1938- January 1971 (has links)
No description available.
87

The governance of sustainable development : exploring networks of collective action on the development of major water resources

Stratton-Short, Samantha Tara Lynn January 2013 (has links)
No description available.
88

Input specifications to stochastic decision models

Clainos, Deme Michael, 1943- January 1972 (has links)
No description available.
89

Operations policy for the Upper Pampanga River Project reservoir system in the Philippines

Franco, Danielito Tan, January 1977 (has links) (PDF)
Thesis (Ph. D. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.
90

Mathematical system theory and the ecosystem concept, an approach to modelling watershed behavior

Rogers, James Joseph, January 1971 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona. / Includes bibliographical references.

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