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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.
61

Campaigns, perceptions, and consumption| A mixed methods study of fresh water management in the inland Northwest

Tillotson, Kathryn Helen 21 August 2015 (has links)
<p> Dwindling freshwater resources are one of the largest challenges facing countries worldwide. For regional and local governments the task of managing fresh water resources falls the hardest. Reduced water quantity directly impacts water quality and thus preventing further depletion of freshwater levels is necessary for meeting existing and forth coming water quality regulations. Thus, finding effective ways to better understand water use at the local or regional level and better ways of communicating pressing water management issues with water users is imperative to the longevity of freshwater resources. Environmental communication campaigns are one way of reaching water users. Understanding water users personal relationship with water resources and nature in general can inform environmental campaigns in multiple ways. </p><p> This research provides insight into the ways in which environmental campaigns can be framed to effectively reach the target audience. Two methods of assessing stakeholder perceptions of water resources are also explored. First, systems thinking is used to compare the mental models of water managers and members of the development sector in order to find areas of common interest and importance regarding the management of freshwater resources in the Spokane-Coeur d'Alene Corridor of northeast Washington and northern Idaho. Second, a survey is used to evaluate characteristics of water use for residents in Spokane County, Washington. </p><p> This dissertation is centered on three primary research questions: (1) How are environmental communication campaigns framed?; (2) How do stakeholder groups who may appear to have very different values for a shared resource perceive a shared that resource?; (3) How do people's perceptions of nature, environmental issues, and their ability to impact those issues influence the way that they use water? Results of this research show that there are key areas of shared interest between water managers and developers suggesting that long-term water management goals do not have to conflict with the goals of local development. This research also suggests that residents who are willing to perform behaviors to reduce their water use are not necessarily doing so, pointing toward further research questions to bridge the gap between willingness and action.</p>
62

Water and sanitation institutions and governance| Impact on service provision in urban areas of low- and middle-income countries

Manderino, Laurie Ann 16 December 2015 (has links)
<p>Rapid global urbanization over the last few decades has intensified the challenge of providing adequate water and sanitation services to urban residents. Meeting this challenge has been the focus of domestic and international development efforts, including Millennium Development Goal 7.C. This research studies three institutional and governance attributes theorized to improve government service outcomes, testing hypotheses that the attributes are associated with greater country progress on providing urban water and sanitation access. The attributes are: a) decentralized services; b) sector-wide strategy and investment coordination; and c) civil society engagement. Country-level experience is analyzed using a series of ordered logistic regression models for a sample of 75 low- and middle-income countries. UN GLAAS survey data is used to derive country-specific variables for the three attributes. These, along with control variables representing country background conditions, are analyzed relative to four country progress outcome variables, two each for water and sanitation. The outcome variables, (covering the 2000 to 2012 time period), are derived from the UN JMP dataset that tracks urban access rates by country. Based on results from these models, four country case studies look in-depth at implementation of the attributes and highlight aspects that can help or impede country progress. Overall, findings show that decentralization is helpful to sanitation progress, but not water progress, likely due limitations of capacity and funding faced by sub-national levels of government. Three explanations are proposed for why decentralization may impact water and sanitation differently. Results for sector planning were mostly inconclusive, except that it was shown helpful to water progress over the 12-year period. Study of this attribute would benefit from additional wide-scale data collection. Civil society engagement was consistently shown to help country progress in both water and sanitation, and several examples of engagement are profiled to demonstrate how it can improve service outcomes. The last chapter relates findings to theories about government provision of public goods. The extent to which the three attributes help achieve efficiency, supply, equity, and social welfare goals is discussed. Finally, practical recommendations for strengthening sector institutions and governance are presented with application to governments and international aid donors.
63

Drinking Water Quality Perception Survey in the SIUE Community

Olagunju, Kehinde 09 June 2018 (has links)
<p> Water quality perception is borne out of various factors, which include taste, risk perception, water chemical and microbial parameters, trust in supplier, among others. This study addressed some of the factors that influence drinking water quality perception in the SIUE community for tap and bottled water. This was done through a survey that was delivered to the students, faculty, administration, staff, and alumni members of the university; a link to the online survey was provided via the school email, and a total number of 779 respondents participated in the survey. Some of the variables used in this study are based on general concern for taste, cost, water-chemicals (such as lead), drinking water behavior as well as demographic variables such as age, knowledge level and ethnicity. This study is based on data received from the survey conducted of the SIUE population for undergraduates, graduates, faculty, staff, administration, and alumni. Data were analyzed using several statistical methods including Spearman rank correlation coefficient and Kruskal-Wallis test. The results indicated that age and ethnicity have a significant impact on water quality perception. Drinking water behavior, age, and knowledge are well correlated in this study; therefore, they were not able to be separated.</p><p>
64

SEASONAL VARIATION IN TEMPERATURE, PRECIPITATION AND STREAMFLOW ACROSS THE MIDWESTERN UNITED STATES

Pathak, Pratik 01 December 2016 (has links)
A great deal of attention has been given to global climate change by the hydrologic community. Temperature, precipitation and streamflow trend analysis, on different spatial and temporal scales, is important in understanding the impact of climate change. Midwest region is the heartland of agriculture production in U.S., and change in hydrologic variables may affect both quantity and quality of production. In the study, mean, maximum and minimum temperature along with mean precipitation for 106 climate divisions in the Midwest were analyzed to test the existence of monotonic trend and shift changes in the seasonal hydrological time series. In addition to that, trend and shift in 88 streamflow stations in the Midwest and its relation with temperature and precipitation were analyzed. Mann Kendall test with and without considering lag-1 auto-correlation were employed to analyze the trend. Non-parametric Pettitt test was used to analyze the shift; Sen’s slope estimator was used to identify the magnitude of hydrological trend. Discrete Wavelet analysis was done to analyze the effect of periodicities on trends and shifts in hydrological variables. In addition, association between the occurrence of shifts and phases of climate indices, such as El Nino Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO), was investigated. The results indicated significant increasing trend in mean and minimum temperature for majority of the climate divisions in all the seasons studied. While, increase in maximum temperature in winter and spring was observed, majority of the climate divisions showed decreasing trend in summer and fall. Increasing trend in precipitation was detected mostly in spring, summer and fall as compared to winter. Persistence was mostly observed for all the variables during the summer season and when accounted for, trend remained for most of the climate divisions. Spatially prevalent shifts were noticed, which were in agreement with gradual trend for most of the hydrologic variables. The results of the wavelet analysis indicated D2 (dyadic scale of 4 years) and D3 (dyadic scale of 8 years) to be the most effective periodic component in detecting trend in winter, spring and summer. D1 (dyadic scale of 2 years) and D3 proved to be the most effective in detecting trend in temperature data in fall. Likewise, precipitation and streamflow showed the dominance of D3 component in detecting real trend in the data. Majority of shift changes coincided with PDO and ENSO phases. The use of wavelet helped in detecting the typical timescale of ENSO and the effect of coupled climate indices on hydrologic variables. A possible linkage between streamflow, temperature and precipitation trend across some regions were detected clearly corroborating the importance of exploring the synergism between meteorological, climatic and hydrologic factors to assess the changing character of the variables. The contribution from this research include a better understanding of the changes in the hydrology of the Midwest that can help in better water management decisions.
65

Embedded Resource Accounting with Applications to Water Embedded in Energy Trade in the Western U.S.

January 2013 (has links)
abstract: Water resource management is becoming increasingly burdened by uncertain and fluctuating conditions resulting from climate change and population growth which place increased demands on already strained resources. Innovative water management schemes are necessary to address the reality of available water supplies. One such approach is the substitution of trade in virtual water for the use of local water supplies. This study provides a review of existing work in the use of virtual water and water footprint methods. Virtual water trade has been shown to be a successful method for addressing water scarcity and decreasing overall water consumption by shifting high water consumptive processes to wetter regions. These results however assume that all water resource supplies are equivalent regardless of physical location and they do not tie directly to economic markets. In this study we introduce a new mathematical framework, Embedded Resource Accounting (ERA), which is a synthesis of several different analytical methods presently used to quantify and describe human interactions with the economy and the natural environment. We define the specifics of the ERA framework in a generic context for the analysis of embedded resource trade in a way that links directly with the economics of that trade. Acknowledging the cyclical nature of water and the abundance of actual water resources on Earth, this study addresses fresh water availability within a given region. That is to say, the quantities of fresh water supplies annually available at acceptable quality for anthropogenic uses. The results of this research provide useful tools for water resource managers and policy makers to inform decision making on, (1) reallocation of local available fresh water resources, and (2) strategic supplementation of those resources with outside fresh water resources via the import of virtual water. / Dissertation/Thesis / Ph.D. Civil and Environmental Engineering 2013
66

Análise dos critérios de outorga de direito de usos consuntivos dos recursos hídricos baseados em vazões mínimas e em vazões de permanência. / Analysis of grant criteria based on minimum flow and flow according to duration curve for water consumptive uses.

Ludmilson Abritta Mendes 16 May 2007 (has links)
A Política Nacional de Recursos Hídricos acaba de completar dez anos, período ao longo do qual novos desafios se apresentaram ao gerenciamento dos recursos hídricos à medida que se consolidou a aplicação dos instrumentos de gestão, dentre eles a outorga de direito de uso. Os critérios comumente aplicados na determinação da disponibilidade hídrica para outorga, ao fixarem vazões muito restritivas como quantidade máxima outorgável, se mostraram inadequados à realidade de algumas bacias, que, em pouco tempo, se apresentaram com disponibilidade hídrica crítica ou em vias de criticidade, tendo a somatória das demandas consuntivas alcançado a restrita parcela destinada à outorga estabelecida em legislação. Neste trabalho buscou-se apresentar as inconveniências relacionadas ao uso da vazão mínima de 7 dias com 10 anos de recorrência - Q7,10 - e das vazões de permanência como referência para outorga. Através das leituras de vazões diárias de dois postos fluviométricos da bacia hidrográfica do rio Turvo, em São Paulo, já considerada crítica quanto à disponibilidade hídrica, foi calculada a Q7,10 por ajustes obtidos por quatro distribuições probabilísticas, e também foi construída a curva de permanência de vazões de ambos os postos. Os resultados foram usados no cálculo da vazão outorgável segundo os critérios estaduais baseados em vazão mínima e em vazão de permanência. Discutem-se, então, as imprecisões associadas à Q7,10 e às vazões de permanência em vários aspectos, bem como as inconveniências de se fixar um teto exíguo e universal de outorga a perfis de demandas distintos. Sugere-se, por fim, o abandono destes critérios de outorga e, a partir de algumas experiências de gestão de bacias críticas, apontam-se caminhos alternativos mais adequados, em especial a outorga negociada. / Through these ten years of the Water Resources Brazilian Policy, some difficulties have been presented to the water resources management in so far as the management instruments has becoming solid, mainly to the grant of right for using water resources. A problem of those refers to the low water availability in several water basins, where the total water demands exceed the maximum volume permitted in agreement with the law. This situation occurs by the state criteria which impose low limits for the surface outflows, expressed by minimum flow or flow according to duration curve. This work analyses the constraints when the hydrologic water availability is referred to the Q7,10 (minimum flow with duration of 7 days duration and 10 years of return period), to Q95% (flow equalized or overstated in 95% of the time) or to Q90%. These flows were calculated from the daily records in two hydrological stations located at Turvo River, State of São Paulo, where the consumptive uses are higher than the water availability. The Q7,10 flow was obtained through four probabilistic methods. Also the duration curves were obtained and the results was used to determine the maximum value granted according to state criteria referred to Q7,10, Q95% and Q90% flows. Then, it\'s argued the imprecision related to these three flows in several aspects and the inconvenience of fixing an scanty and universal ceiling to different demands profiles. In conclusion, it\'s suggested the substitution of these criteria and, through some cases of management of critical basins, it\'s pointed alternative methods of grant of right for using water resources.
67

Critical analysis in the process of granting the state of CearÃ: a case study in the Valley of the River Curu / AnÃlise crÃtica no processo de outorga no Estado do CearÃ: estudo de caso no Vale do Rio Curu.

Adriana DÃbora Chagas de AraÃjo 28 April 2014 (has links)
nÃo hà / This paper presents a proposal for the grant application as a management tool in the allocation to the valley of Curu river in the state of CearÃ. Were developed and presented historical series of simulations of reservoirs, as well as assumptions of using the grant as a tool for allocation, based on water demands of the Curu river valley. Were estimated by registering the demands of users conducted by COGERH in 2013 and the record of the grants awarded in the same year. Simulations with Sagreh and ACQUANET programs for the following year, including an estimate of growth in the region that still has a number of large areas into disuse were also made. Observing the variables found a study on the risk of not meeting the demands, based on historical series of scarcity and reduction of flow was made. This study applied if the demands: estimated, granted and maximum theoretically and tested a strategy for the grant application as a management tool to be considered in the allocation to systematize the use of water in the basin and the river valley Curu. / Este trabalho apresenta uma proposta para a aplicaÃÃo da outorga como um instrumento de gestÃo na alocaÃÃo para o vale do rio Curu, no estado do CearÃ. Foram trabalhadas e apresentadas sÃries histÃricas de simulaÃÃes dos reservatÃrios, assim como suposiÃÃes do uso da outorga como instrumento para alocaÃÃo, tendo por base as demandas de Ãgua do vale do rio Curu. Estimaram-se as demandas atravÃs do cadastro de usuÃrios realizado pela Cogerh no ano de 2013 e do registro das outorgas concedidas no mesmo ano. TambÃm foram efetuadas simulaÃÃes com os programas Sagreh e Acquanet para os anos seguintes, incluindo uma estimativa de crescimento da regiÃo que ainda possui um grande nÃmero de Ãreas em desuso. Observando as variÃveis encontradas foi efetuado um estudo sobre o risco do nÃo atendimento das demandas, baseado em sÃries histÃricas de escassez e reduÃÃo de vazÃo. Neste estudo aplicaram-se as demandas: estimadas, outorgadas e mÃximas e testou-se teoricamente uma estratÃgia para aplicaÃÃo da outorga como instrumento de gestÃo a ser considerada na alocaÃÃo de modo a sistematizar o uso da Ãgua na bacia hidrogrÃfica e no vale do rio Curu.
68

Research and Education on Water-Energy Nexus| Impact of Hydraulic Fracturing and Thermal Power Generation on Water Resources

Unruh, Hanz 05 May 2018 (has links)
<p> Unconventional oil and gas extraction has been deployed significantly in the United States in recent years. The current study focuses on the impact of hydraulic fracturing (also known as fracking) on the sustainability of water resources in Louisiana. This impact is measured by quantifying the stress for current and future scenarios of fracking water use in the two main shale plays in Louisiana. The assessment is conducted at the HUC-12 fine catchment spatial scale. Initially, sectored stress metrics were calculated for surface and groundwater, respectively, without including fracking water use. Once both stress metrics were estimated with the reported water sources and uses in Louisiana corresponding to the 2010 year, several scenarios for both sources were evaluated. In the <i>first scenario</i>, a peak year (2011) of fracking water use was added as a water demand new category into the stress calculation matrices. The results indicate that a significant variability in the calculated stress metric with and without fracking is reflected only for the groundwater sector. The second <i>Existing wells</i> scenario calculates the stress including the water use of the total number of wells that currently exist in both shale plays over a brief time period. The other additional tested scenario consists of an increase of 100% of the required number of wells to extract the expected total shale play capacity. Results of the <i>additional scenarios</i> follow the same pattern as the <i> first scenario</i>. This analysis can be useful for water management authorities to consider several factors, such as cost analysis of recycled flow-back, as alternative resources for fracking water use. In addition to this fracking water use impact on resources analysis, an educational web-module comprising the Energy-Water Nexus is developed in the current study. The core of the educational module available online is contained in the learning activities development.</p><p>
69

Resolving Spatial and Temporal Variability in Dissolved Organic Matter Characteristics within Combined Agricultural and Stormwater Conveyances

Mihalevich, Bryce A. 09 September 2017 (has links)
<p> Dissolved organic matter (DOM) plays an important role in the cycling of nutrients within aquatic ecosystems; however, excess amounts can have detrimental effects on aquatic organisms. Stormwater runoff events in urban areas can contribute high concentrations of DOM to receiving waters, posing potential impairment to the aquatic ecosystems of urban streams and downstream water bodies. Characterizing compositional changes in DOM due to storm events is important for understanding potential downstream water quality effects and has been well studied in forested, agricultural, and urban landscapes. However, <i>in situ</i> sensors have not been widely applied to monitor stormwater contributions in urbanized areas, leaving the spatial and temporal characteristics within these systems poorly understood. Using laboratory measurements of dissolved organic carbon (DOC) concentration and excitation emission matrix spectroscopy (EEMS), fluorescent DOM (FDOM) sensors, and a mobile water quality sensing platform, this study investigated changes in DOM quantity and sources within the Northwest Field Canal (NWFC), an urban water conveyance located in Logan, Utah, USA that receives runoff during storm events. Under baseflow conditions, FDOM decreased and exhibited dampened diurnal variability as the summer irrigation season progressed, while FDOM values at the upstream and downstream monitoring sites were relatively similar. During storm events, FDOM concentrations were rapidly elevated to values orders of magnitude greater than in baseflow measurements, and DOC concentrations were more than 3 times greater at the downstream site than those at the upstream site due to high contributions of DOC being discharged from outfalls. Compositional changes in DOM indicated a shift during storm events from a more autochthonous, less degraded DOM in baseflow to more decomposed and terrestrially derived DOM in stormwater flows. These observations were consistent with results from custom, <i>in situ</i> fluorometers, which also revealed a seasonal transition to a more microbially derived composition in baseflow conditions as the summer season progressed. Deployment of a mobile sensing platform during stormflow conditions confirmed that contributions of DOM were associated with the locations of outfalls discharging runoff into the canal and revealed spatial changes in DOM composition and concentration along canal transects.</p><p>
70

Empowered women in water management

Zonde, Memory January 2007 (has links)
Magister Philosophiae - MPhil / Following South Africa's independence from apartheid rule, there has been progressive developments in policies that promote equity in all spheres including the water sector. Equality in the water sector is not only limited to water access, but also management of the water. This study investigated the factors that empower women in the water sector as an example of gender equity. / South Africa

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