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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.
361

A Discussion of the Impact of Political and Economic Forces on Equitable Access to Potable Water in Ecuador and Recommendations for Improvement through Better Watershed Management

States, Eliza 01 January 2014 (has links)
This thesis will address the impact of political and economic forces on the equitable access to fresh water in Ecuador. Demographic factors such as the rural-to-urban migration and the political and economic forces have strongly influenced the debate over the privatization of the provision of potable water and sanitation services. Within the context of Ecuador, two different approaches by the largest cities, Quito and Guayaquil, are analyzed; in Guayaquil, the services were privatized, while in Quito, the public utility was corporatized, remaining under public control. It concludes arguing that in the face of political instability and a lack of regulatory enforcement, neither public nor private provision adequately supplies marginalized communities with water and sanitation services. Watershed management is therefore crucial to maintaining a sound city water-management plan. Its flexibility and openness to innovative alliances between various stakeholders creates great potential for this approach.
362

Effects of Watershed Dynamics on Water Reservoir Operation Planning : Considering the Dynamic Effects of Streamflow in Hydropower Operation

Zmijewski, Nicholas January 2017 (has links)
Water reservoirs are used to regulate river discharge for a variety of reasons, such as flood mitigation, water availability for irrigation, municipal consumption and power production purposes. Recent efforts to increase the amount of renewable power production have seen an increase in intermittent climate-variable power production due to wind and solar power production. The additional variable energy production has increased the need for regulating the capacity of the electrical system, to which hydropower production is a significant contributor. The hydraulic impact on the time lags of flows between production stations have often largely been ignored in optimization planning models in favor of computational efficiency and simplicity. In this thesis, the hydrodynamics in the stream network connecting managed reservoirs were described using the kinematic-diffusive wave (KD) equation, which was implemented in optimization schemes to illustrate the effects of wave diffusion in flow stretches on the resulting production schedule. The effect of wave diffusion within a watershed on the variance of the discharge hydrograph within a river network was also analyzed using a spectral approach, illustrating that wave diffusion increases the variance of the hydrograph while the regulation of reservoirs generally increases the variance of the hydrograph over primarily short periods. Although stream hydrodynamics can increase the potential regulation capacity, the total capacity for power regulation in the Swedish reservoir system also depends significantly on the variability in climatic variables. Alternative formulations of the environmental objectives, which are often imposed as hard constraints on discharge, were further examined. The trade-off between the objectives of hydropower production and improvement of water quality in downstream areas was examined to potentially improve the ecological and aquatic environments and the regulation capacity of the network of reservoirs. / <p>QC 20170210</p>
363

Trace Metal Analysis of Barren River and Nolin River Reservoirs by Atomic Absorption Spectroscopy

Kennedy, Mary Jo 01 July 1969 (has links)
This research was part of a project underway at Barren River and Nolin River Reservoirs in south-central Kentucky. The research was partially supported by a grant through the Sport Fishing Institute, Washington, D.C. The study reported herein was concerned with the analysis of trace metal concentrations in the two reservoirs. It is believed that the fish population may in part depend upon the trace metals present in the water. It is anticipated that the data presented in this paper will eventually be correlated with the biology studies of the reservoirs being carried out by the Department of Biology of Western Kentucky University.
364

"Mining" for a Reference Condition in Southern West Virginia Streams

Rouch, Matthew 01 January 2014 (has links)
Quarterly samples were used to estimate assemblage-level (all species combined) fish production within three minimally-impacted, southern West Virginia streams. The total annual fish production estimate was highest in Slaunch Fork (37.52 kg∙ha-1∙y-1), a tributary of the Tug Fork River, and lowest in Cabin Creek (10.59 kg∙ha-1∙y-1), a Guyandotte River tributary. Creek Chub Semotilus atromaculatus, Mottled Sculpin Cottus bairdii and Blacknose Dace Rhinicthys atratulus were the most abundant species among sites, accounting for >90% of all sampled individuals. Reference condition criteria were also selected and metrics calculated for each of the three stream sites using a variety of established metrics. According to established criteria, all three of our sites scored high enough to be listed as “reference” sites. Third, a comprehensive GIS analysis was conducted in order to determine land use patterns and predict where similar assemblages would be present using various climatological and physical characteristics of our stream sites. These analyses revealed rapid expansion of surface mining activities putting many stream systems at risk.
365

Nyckelfaktorer för en förbättrad samverkan mellan markavvattningsföretag och kommuner vid stadsutveckling / Key factors for an improved cooperation between agricultural drainage organizations and municipalities in case of urbanization

Nyström, Jennifer, Obeido, Anwar January 2019 (has links)
Syfte: Fokus på dagvattenhantering är viktigt eftersom översvämnings- och föroreningsrisker blir allt mer förekommande på grund av klimatförändringar och urbanisering med en ökad andel hårdgjorda ytor. Vid exploatering vill kommuner utnyttja befintliga diken istället för att bygga nya ledningssystem, därmed kan de behöva samverka med markavvattningsföretag. Syftet med studien är att underlätta samarbetet mellan markavvattningsföretag och kommuner för att undvika översvämningar och föroreningar som förändring av stad och klimat kan medföra. Målet är att identifiera faktorer som kan förbättra samverkan mellan markavvattnings-företag och kommuner. Metod: Studien utgår ifrån en fallstudie som består av kommuner som har samverkat med markavvattningsföretag. De datainsamlingsmetoder som använts för att besvara frågeställningarna är litteraturstudier och semistrukturerade intervjuer med kommuner som har erfarenhet av sådana samverkansprocesser; Linköping och Norrköping. Resultat: De faktorer som kan förbättra samverkan är framförallt kommunikationen mellan parterna för att finna ömsesidiga nyttor och att uppdatera registren över markavvattningsföretag. Fallstudien har visat att förbättring av samverkan kan uppnås genom rådgivningsstöd från en transparent aktör. Norrköpings kommun önskar bland annat en enkel handbok som är framtagen av någon myndighet för att få det transparent och som är anpassad för aktörer med mindre kännedom kring processen. Fallstudien har även påvisat att markavvattningsföretag är en intressent som har hög angelägenhet att påverka projekt samtidigt som de har makt att styra projektets tidsaspekt. Dessa är projektets nyckelintressenter som är viktiga aktörer för projektets helhet och som måste prioriteras, hållas informerade och nöjda för att underlätta samverkan. För att upprätthålla en hållbar stadsutveckling behöver översvämnings- och föroreningsrisker minskas för att skydda naturresurser och bevara den biologiska mångfalden. Öppna diken mildrar belastningen på avloppssystemen som i sin tur minskar risker för översvämningar och främjar biologisk mångfald. Konsekvenser: Kännedom om betydelse av användandet av öppna diken är nödvändigt för att upprätthålla hållbar stadsutveckling. Det saknas uppgifter i registren över markavvattningsföretag eftersom de inte är uppdaterade. Det kan därmed bli ett detektivarbete för kommuner att komma fram till rätt person. Denna problematik medför även att en del markavvattningsföretag saknar kännedom om dess roll i projekten. Det finns dessutom ingen myndighet att rådfråga i dessa samverkansprojekt. Begränsningar: Det var endast kommuner med erfarenheter av dessa projekt som inkluderades i undersökningen eftersom frågeställningarna krävde viss kännedom om markavvattningsföretag. Det var även lämpligt att endast ta hänsyn till faktorer som berör samverkansprocessen, utan att studera övriga påverkande aspekter såsom jordens permeabilitet eller växters vattenupptag eftersom detta inte påverkar studiens utfall. / Purpose: Focus on stormwater management is important because water pollution and flood risks are increasingly anticipated effects of climate change and urbanization. In case of urban growth areas, municipalities want to exploit the existing ditches rather than install new pipes. Here cooperation with agricultural drainage organizations may be required. This study contains exposition of key factors to facilitate such cooperation’s to support sustainable urban development. The purpose of this study is to facilitate the cooperation between agricultural drainage organizations and municipalities in order to avoid flooding and pollution which urbanization and climate change can result in. The objective is to identify factors that can help improve cooperation between agricultural drainage organizations and municipalities. Method: The study was carried out as a case study of municipal cooperation with agricultural drainage organizations. Data was collected from literature studies and semi-structured interviews with municipalities with previous such experiences; Linköping and Norrköping. Findings: The factors that can improve cooperation are foremost communication between both parties in order to find mutual benefits and to keep the registers over agricultural drainage organizations updated. This case study has shown that improvement of collaboration can be achieved through counseling support from a transparent actor. Norrköping Municipality wishes for a simple handbook accessible even to actors with little to no prior knowledge about the process. The case study has also shown that agricultural drainage organizations are stakeholders who have a high interest in influencing projects while also having the power to control the project's time aspect. These are the key stakeholders of the project, who are important players for the project as a whole and who must be prioritized, kept informed and satisfied to facilitate collaboration. To maintain sustainable urban development the risks of flooding and water pollution need to be minimized to protect biodiversity. Open ditches mitigate the load on drainage systems which reduces the risk of flooding and support biodiversity. Implications: Knowledge of the importance in using open ditches is necessary to maintain sustainable urban development. There is data missing in the registers over agricultural drainage organizations since they are not updated. This results in difficulties for municipalities when trying to reach the correct person. This problem also results in some agricultural drainage organizations missing knowledge of their part in projects. There is also no authority to consult in these cooperative projects. Limitations: The study does not consider other aspects beside the cooperation between municipalities and agricultural drainage organizations. Only municipalities with prior experience of working with agricultural drainage organizations were questioned as the questions required certain knowledge about these processes. It was also appropriate to only consider factors that affect the cooperative process without studying other affecting aspects like the permeability or water uptake of plants since this does not affect the results of the study.
366

Regionalização hidrológica do Estado de Santa Catarina: uma abordagem sazonal e geoestatística baseada em modelos / Hydrologic regionalization of Santa Catarina state: a seasonal and geostatistical approach based on models

Wolff, Wagner 12 January 2017 (has links)
A regionalização hidrológica é uma técnica que permite transferir informação de regiões hidrologicamente monitoradas, para regiões com pouco ou sem monitoramento. Sendo assim, é uma ferramenta útil, a qual permite uma avaliação dinâmica dos recursos hídricos. No Brasil e no Estado de Santa Catarina as leis que são as principais referências para a gestão de recursos hídricos utilizam critérios anuais de disponibilidade hídrica, impossibilitando um maior uso em épocas onde a disponibilidade é maior e, assim, afetando o desenvolvimento econômico. As previsões sazonais servem de base para uma gestão e utilização sustentável dos recursos hídricos. A justificativa de não se usar critérios sazonais, talvez seja pelo fato de não existir trabalhos ou ferramentas que contemplam o estado da arte da regionalização hidrológica. O objetivo deste trabalho é fazer a regionalização hidrológica do Estado de Santa Catarina, mediante uma abordagem geoestatística baseada em modelos e na sazonalidade. Foram utilizados estações pluviométricas e fluviométricas disponibilizadas, respectivamente, pela Companhia de Pesquisa de Recursos Minerais (CPRM) e Agência Nacional das Águas (ANA). As estações são distribuídas regularmente e em alta densidade sobre o Estado. Para a modelagem geoestatística, inicialmente foi verificada algumas suposições a serem consideradas, entre elas, a normalidade e a estacionaridade espacial dos dados. Após as suposições terem sido aceitas foi verificado, por meio de testes estatísticos em função da verossimilhança, se a estrutura de dependência espacial do modelo geoestatístico aumentava o desempenho do mesmo, justificando o uso dessa estrutura para a espacialização das variáveis pluviométricas e fluviométricas. Para verificar os pressupostos de uma boa predição, foi avaliada a dispersão dos resíduos das interpolações espaciais, mediante uma validação cruzada. Os resultados mostraram um melhor desempenho para os modelos geoestatísticos com a estrutura de dependência espacial, para todas as variáveis; assim, esses modelos foram utilizados para a interpolação espacial, no qual foi observado pela dispersão dos resíduos uma boa predição. Este trabalho contribui para uma melhor representação espacial de variáveis sazonais no Estado de Santa Catarina e permite um avanço no estado da arte, uma vez que está embasado em critérios de verossimilhança para escolha de modelos que representam melhor o fenômeno estudado no espaço. / Hydrologic regionalization is a technique that allows the transfer of information from regions hydrologically monitored, for regions with little or no monitoring. Therefore, this technique allows a dynamic evaluation of water resources being a useful tool. In Brazil and in Santa Catarina state, the laws that are the main references for the management of water resources use annual criteria of water availability. Thus, using a greater amount of resources when availability is greater is infeasible and affects economic development. Seasonal forecasts provide the basis for sustainable management and use of water resources. The justification for not using seasonal criteria may be because there are no works or tools that contemplate the state of the art of hydrologic regionalization. The aim of this work is to make the hydrologic regionalization of Santa Catarina state, using a geostatistical approach based on models and in seasonality. Data from rain gauge and streamflow stations made available by the Mineral Resources Research Company (CPRM) and National Water Agency (ANA), respectively, were used. These stations have regular distribution and high density within the state. For the geostatistical modeling, some basic assumptions such as data normality and spatial stationarity were verified. After accepting the assumptions it was verified through statistical tests regarding its likelihood, if the structure of spatial dependence of the geostatistical model increase its performance, justifying the use of this structure for the precipitation and streamflow spatialization. To check the assumptions of good prediction, the residue dispersion of the spatial interpolations was evaluated through cross-validation. The results showed a better performance for the geostatiscal models with the spatial dependence structure, both for precipitation and streamflow. Thus, these models were used to the spatial interpolation, observing a good prediction through the residue dispersion. This work contributes to a better spatial representation of seasonal variables in Santa Catarina state and allows an advance in the state of the art, since it is based on likelihood criteria to choose models that better represent the phenomenon studied in space.
367

The law and policy governing inter-basin transfers of freshwater resources in the Southern African Development Community (SADC) region

Sefela, Glenwin January 2011 (has links)
Magister Legum - LLM / Water scarcity is a worldwide threat. Fresh water resources are vital to human existence and survival. The challenge faced relates to the way these water resources are being distributed and managed. As an answer to this challenge, humans responded with what is commonly known as water transfers. A water transfer refers to the importation of water where water supply is low. Water transfers are, however, not a new concept as it dates back to the ancient Mesopotamians. Today, due to the global population having drastically increased, water transfers, or inter-basin transfers (IBTs) are increasingly being used as a means to minimize current water shortages.
368

Índice de sustentabilidade dos recursos hídricos por meio do pensamento sistêmico no município de Promissão, SP / Sustainability index of water resources through systemic thought in the municipality of Promisión, SP / Índice de sostenibilidad de los recursos hídricos Pensamiento sistémico medio de la Promesa municipio, SP

Sachiavon, Adriana Rossi Barbosa [UNESP] 27 January 2017 (has links)
Submitted by ADRIANA ROSSI BARBOSA SCHIAVON null (adriana@unilins.edu.br) on 2017-03-18T14:02:57Z No. of bitstreams: 1 dissertacaoFinalARBSFIM.pdf: 1877576 bytes, checksum: ff5b5a326dd1ad109ba66e4f26fc116e (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-03-21T20:48:05Z (GMT) No. of bitstreams: 1 schiavon_arb_me_bot.pdf: 1877576 bytes, checksum: ff5b5a326dd1ad109ba66e4f26fc116e (MD5) / Made available in DSpace on 2017-03-21T20:48:05Z (GMT). No. of bitstreams: 1 schiavon_arb_me_bot.pdf: 1877576 bytes, checksum: ff5b5a326dd1ad109ba66e4f26fc116e (MD5) Previous issue date: 2017-01-27 / O presente trabalho teve por objetivo desenvolver um modelo em dinâmica de sistemas, propondo assim, uma ferramenta que permitisse a análise da sustentabilidade dos recursos hídricos do município de Promissão, interior do estado de São Paulo. Este modelo para gestão de recursos hídricos auxiliará gestores da bacia hidrográfica do Córrego Gonzaga e à companhia municipal responsável pelo planejamento e gestão de sistema de abastecimento e distribuição de água tratada e esgotamento sanitário, à tomada de decisões com maior embasamento já que permite uma visão sistêmica do processo de abastecimento do município. Para desenvolver o modelo, foi utilizada a metodologia sistêmica que é uma ferramenta de grande valia para os gestores de recursos hídricos, pois permite a previsão de cenários futuros de abastecimento e tratamento de efluentes e viabiliza a elaboração e implementação de políticas públicas. O programa STELLA (Structural Thinking Experimental Learning Laboratory with Animation), versão 9.1.3, foi utilizado para desenvolver o modelo dinâmico. Para elaboração e validação da mecânica do modelo desenvolvido, foram utilizados dados da atual gestão de recursos hídricos do município. O modelo desenvolvido foi o “Modelo de Recursos Hídricos de Promissão (MRH-PROMI)”. Para analisar a sustentabilidade dos recursos hídricos do município de Promissão através dos resultados gerados pelo MRH-PROMI, foram elaborados cinco cenários com situações adversas e analisou-se o comportamento dos elementos envolvidos no processo de Oferta e Demanda do município em cada situação. O modelo desenvolvido, permite que os gestores de água façam planejamentos para evitar os possíveis problemas relacionados ao novo cenário ou elaborem projetos com informações geradas pelo modelo para manutenção e melhoria do uso destes recursos. Para cada cenário calculou-se o índice de sustentabilidade (IS) que permitiu conhecer se os recursos hídricos se manteriam ou não sustentáveis no período de 2005 a 2050. Após a análise do comportamento das variáveis dos cinco cenários, concluiu-se que atualmente, os recursos hídricos do município de Promissão atende às suas demandas sustentavelmente apresentando um desempenho médio, utilizando cerca de 40% de sua capacidade. / This study aimed to develop a model usinf dynamic systems, thus proposing a tool that allows the analysis of water resources sustainability at Promissão, state of São Paulo. This water management model will help managers of the Gonzaga Stream watershed and the municipal company responsible for the management and distribution of treated water and sewage, to decision making with better basis as it allows a systemic view the municipality of supply process. To develop the model, systemic methodology was used which is a valuable tool for water resources managers, it allows the prediction of future scenarios of supply and wastewater treatment and enables the development and implementation of public policies. STELLA software (Structural Learning Laboratory Experimental Thinking with Animation), version 9.1.3, was used to develop the dynamic model. To design and mechanical validation of the developed model, the current water resources management in the municipality data were used. The model was the "Water Resources Model Promissão (WRM-PROMI)." To analyze the water resources sustainability Promissão municipality through the results generated by the MRH-PROMI were prepared five scenarios with adverse situations and analyzed the behavior of the elements involved in the offer process and municipal demand in every situation. The model allows water managers make plans to avoid potential problems related to the new scenario or develop projects with information generated by the model for maintaining and improving the use of these resources. For each scenario we calculated the sustainability index (SI) which allowed us to know if the water would continue or not sustainable in the period from 2005 to 2050. After analyzing the behavior of the variables of the five scenarios, it was concluded that currently, water resources Promissão municipality meets its demands sustainably with an average performance, using about 40% of its capacity.
369

Using Kriging, Cokriging, and GIS to Visualize Fe and Mn in Groundwater

Johnson, Crystal 01 May 2015 (has links)
For aesthetic, economic, and health-related reasons, allowable concentrations of iron (Fe) and manganese (Mn) found present in drinking water are 0.3 mg/L and 0.05 mg/L, respectively. Water samples taken from private drinking wells in the rural communities within Buncombe County, North Carolina contain amounts of these metals in concentrations higher than the suggested limits. This study focused on bedrock geology, elevation, saprolite thickness, and well depth to determine factors affecting Fe and Mn. Using ArcGIS 10.2, spatial trends in Fe and Mn concentrations ranges were visualized, and estimates of the metal concentrations were interpolated to unmonitored areas. Results from this analysis were used to create a map that delineates the actual spatial distribution of Fe and Mn. The study also established a statistically significant correlation between Fe and Mn concentrations, which can be attributed to bedrock geology. Additionally, higher Fe in groundwater was concentrated in shallower wells and valley areas.
370

Perspectives on Policy Framework for Trans-Boundary Water Quality Management in China

Zhang, Wei, Zhen, Gengchong, Tong, Yindong, Yang, Lei, Zhu, Yan, Liu, Guohua, Wang, Xuejun, Li, Ying 02 April 2016 (has links)
In river basins that cross jurisdictional boundaries, water quality degradation has become a crucial problem and results in intensive competition among water users, especially in developing countries. Under this situation, implementing water quality management and control across jurisdictional boundaries can strengthen watershed pollution controls, and prevent pollution from being passed on and promote active pollution control within the related jurisdictional regions. This study examined the limitations of the current trans-boundary water quality management system in China and reviewed the planning and implementation of two pilot integrated trans-boundary water management systems established in the Jiangsu and Zhejiang provinces. Based on our findings, we proposed a new policy framework for trans-boundary water quality management. As a first step toward integrated watershed management in China, this policy framework can help assess the actual water pollution status of various regions and serve as a basis for an integrated watershed management system. The framework can be easily applied in other countries with trans-boundary water pollution issues, particularly in the context of developing countries.

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