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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.
11

Integrated river sustainability assessment : case studies of the Yellow River and the Ganges

Wu, Huijuan January 2014 (has links)
This thesis develops and validates a comprehensive methodology for measuring sustainability of a large river basin by using a tailored indicator set. The concept of river sustainability concerns not only the ecological condition of the river course, but also socioeconomic activities in the river basin. River sustainability is defined from five perspectives: sufficient resource, resilience to water-related risks, access to water supply and other services, productive use of water, and fairness between different users and generations. The Process Analysis Method (PAM) is employed as the guideline for developing sustainability assessment framework. As a participatory approach, PAM engages stakeholders to identify emerging issues and impacts on sustainability. Through a systematic process, a tailored indicator set is selected and categorized under three domains, namely, environmental performance, social wellbeing, and economic development. Two case studies have been undertaken, examining the underlying sustainability of the Lower Yellow River basin (LYR) and Upper Ganges River basin (UGR). Extensive fieldwork was carried out in China and India, in order to conduct stakeholder interviews and to collect multivariate data. 18 indicators are selected for LYR and 12 for UGR. The LYR assessment is conducted over the period from 1950 to 2010, whilst UGR features a 10-year period from 2001 to 2010. By processing raw hydrological data and socio-economic statistics, a normalized score is calculated for each indicator in a given year, the value ranging between 0 and 1, where 0 represents poor performance and 1 refers to a fully sustainable status. The results show that, although social wellbeing and economic status for LYR have progressively improved since 1950, environmental quality declined in the latter half of 20th century, with the lowest point in 1997 when extreme drought occurred. The Yellow River Conservancy Commission (YRCC), the government authority responsible for the LYR, implemented measures to improve the river health by multifunctional infrastructure projects and water allocation regulation. This effort proved to be effective as the general sustainability performance subsequently improved. The UGR study also identifies the trade-off between environmental capital and socioeconomic capital. With vast expansion of hydropower projects and new settlement in flood-prone areas, communities along the UGR are increasingly vulnerable to extreme events. However, the Ganges river basin authority lacks the capacity for integrated planning which would enable projects like flood defence schemes to be undertaken in a proper framework. It is likely that the environmental performance of the UGR will continue to decline, particularly with increasing uncertainty in climate, as the UGR basin management is not improving resilience sufficiently. By performing this comparative analysis, it has been shown that integrated river basin management should incorporate institutional capacity, stakeholder engagement, resilience and transparency. This research also contributes to underpinning policies for Integrated River Basin Management (IRBM). The assessment provides policy-makers and river managers with a holistic view of the river basin; the framework can be used to track progress towards sustainable development and identify priorities for multi-criteria decision-making.
12

From water resources management to integrated water resources management: an analysis of the establishment of new water management organisations in Namibia

Simataa, Faith Auguste January 2010 (has links)
Magister Scientiae (Integrated Water Resource Management) / The questions posed in this study address the different processes that were involved in the decision-making and establishment of the water management organisations, the extent of public participation, as well as features of evident governance in implementing the policies. A critical analysis of the role of stakeholders and the various influences they may have in water management will also be examined. The methodology follows a historical study approach. A thorough document review will be done of the policies and related materials around BMCs, where events will be constructed from the findings. Interviews will be conducted for verification purposes, to verify the desktop findings and to assimilate any conflicts of opinion that might have not been documented. / South Africa
13

Integrated Systems Modeling to Improve Watershed Habitat Management and Decision Making

Alafifi, Ayman H. 01 May 2018 (has links)
Regulated rivers provide opportunities to improve habitat quality by managing the times, locations, and magnitudes of reservoir releases and diversions across the watershed. To identify these opportunities, managers select priority species and determine when, where, and how to allocate water between competing human and environmental users in the basin. Systems models have been used to recommend allocation of water between species. However, many models consider species’ water needs as constraints on instream flow that is managed to maximize human beneficial uses. Many models also incorporate uncertainty in the system and report an overwhelmingly large number of management alternatives. This dissertation presents three new novel models to recommend the allocation of water and money to improve habitat quality. The new models also facilitate communicating model results to managers and to the public. First, a new measurable and observable habitat metric quantifies habitat area and quality for priority aquatic, floodplain, and wetland habitat species. The metric is embedded in a systems model as an ecological objective to maximize. The systems model helps managers to identify times and locations at which to apply scarce water to most improve habitat area and quality for multiple competing species. Second, a cluster analysis approach is introduced to reduce large dimensional uncertainty problems in habitat models and focus management efforts on the important parameters to measure and monitor more carefully. The approach includes manager preferences in the search for clusters. It identifies a few, easy-to-interpret management options from a large multivariate space of possible alternatives. Third, an open-access web tool helps water resources modelers display model outputs on an interactive web map. The tool allows modelers to construct node-link networks on a web map and facilitates sharing and visualizing spatial and temporal model outputs. The dissertation applies all three studies to the Lower Bear River, Utah, to guide ongoing habitat conservation efforts, recommend water allocation strategies, and provide important insights on ways to improve overall habitat quality and area.
14

Modelling of pesticides and POPS in the River Thames system : potential impacts of changes in climate and management

Lu, Qiong January 2017 (has links)
Due to environmental concerns, most of persistent organic pollutants (POPs) have been eliminated or reduced in production and use; however, due to their great persistency, POPs are expected still to be found in the environment long after their use has ceased. Although, in recent years, POPs have rarely been detected in river water in the United Kingdom (UK), their concentrations in fish (biota) and sediment are expected to be notable due to their lipophilicity and bioaccumulation; however, there is a lack of information and data to understand the current contamination of POPs in catchments and evaluate their potential risk to the environment and ecosystem. This thesis describes the application of mathematical modelling approaches to (i) predict the current distribution and concentration of POPs in catchments, (ii) evaluate the influence of climate change and extreme weather conditions on the fate of POPs, and (iii) provide guidelines to inform decision-making on managing the potential risks of POPs in river basins. The modelling studies have mainly focused on polychlorinated biphenyls (PCBs). The River Thames catchment was chosen as the study area. The Fugacity level III model was initially used to describe the general distribution of PCBs between different compartments; it was predicted that the greatest mass of PCBs remain in the soil, but the fish and sediments represent compartments with the highest PCB concentrations. The contamination of PCBs in Thames fish was estimated to exceed the unrestricted consumption thresholds of 5.9 μg/kg for ∑PCBs set by the U.S. Environmental Protection Agency (EPA); no current EU Environmental Quality Standards (EQS) are available for PCBs in fish. It was indicated that the PCBs in fish could be linked to PCB contamination in sediment, which was predicted to be about three times higher than the fish concentrations, but insufficient observed data of PCBs in Thames fish and sediment are available to validate the results. In order to address this limitation in observed data, fish and sediment sampling and chemical analysis were carried out for the presence of POPs. In addition to PCBs, the measured results for hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) in Thames fish and sediment were assessed. Although the observed fish- and sediment concentrations of the chemicals appear quite variable, when normalised to organic carbon the levels in sediment, they were comparable to the fish lipid normalised concentrations. Using the temperature and rainfall data forecasts in the UK Climate Projections 2009 (UKCP09), climate change scenarios were established and assessed in the fugacity modelling. The modelling results suggested a modest influence of climate change on PCB fate over the next 80 years. The most significant result was a tendency, in the Thames catchment, for climate change to enhance the evaporation of PCBs from soil to air. While the fugacity model successfully simulated the distribution and fate of PCBs, we used greatly simplified representations of climate, hydrology and biogeochemical processes of the catchment: to have a deeper understanding, a newly developed dynamic hydrobiogeochemical transport model - the Integrated Catchment Contaminants model (INCAContaminants) was applied. Using additional information about weather, river flows and water chemistry, the INCA-Contaminants model provided new insights into the behaviour of contaminants in the catchment; this led to a better representation of PCB contamination in sediment. In addition, INCA demonstrated the important impact of short-term weather variation on PCB movement through the environment. It was shown that PCBs contamination in Thames sediment was greatly disturbed by the severe flooding that occurred in early 2014. This thesis presents the application of the INCA model to assess - in addition to POPs - the behaviour of metaldehyde in the River Thames catchment. Metaldehyde is a type of pesticide used mainly to kill snails and slugs. Its application in agricultural areas within the catchment area has in recent years caused severe problems with drinking water supply. The INCA model has proved to be an effective tool for simulating the transport of metaldehyde in the catchment, predicting observed metaldehyde concentrations at multiple locations in the River Thames; this is the first time that a dynamic modelling approach has been used to predict the behaviour of metaldehyde in river basins. Modelling results showed that high concentrations of metaldehyde in the river system are a direct consequence of excessive application rates. In this thesis, a simple decision-support tool was derived from modelling results, based on variable application rates and application areas. This decision-support tool is now being used by Thames Water to help control peak concentrations of metaldehyde at key water supply locations.
15

People's Water and River Perceptions in the Selangor River Basin, Malaysia / マレーシア国セランゴール川流域における人々の水と川に対する意識に関する研究

Shimizu, Daigo 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22426号 / 工博第4687号 / 新制||工||1732(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 清水 芳久, 教授 田中 宏明, 教授 藤井 滋穂 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
16

Exposure and risk assessment of pharmaceuticals in challenging watersheds by enhanced geo-referenced modelling

Lämmchen, Volker 20 December 2021 (has links)
For this work the Geo-referenced Regional Exposure Assessment Tool for European Rivers (GREAT-ER) was developed further to support river basin management and the implementation process within the EU Water Framework Directive (WFD). This was achieved through predicting spatially resolved pharmaceutical exposure concentrations in whole watersheds. A major focus of this thesis has been placed on modeling challenging watersheds, whereby challenging can refer to hydrological conditions in a watershed as well as to specific emission patterns that occur within the watersheds. The adapted methodology improves the prediction accuracy in such watersheds with GREAT-ER with respect to pharmaceutical exposures, but can also lead to improved results in other application areas. The possibilities of the latest model version are demonstrated by the extensive inclusion of local and regional conditions. In watersheds with highly variable and seasonally changing hydrological situations, GREAT-ER has been applied satisfactorily for the first time, and additionally, the developed approach can be transferred to equivalent watersheds worldwide. Comparison with monitoring data confirms that some of the adjustments have resulted in significantly improved model predictions, especially when hydrological and local conditions are specifically addressed. For example, explicit consideration of local drug emissions from hospitals or private medical practices (e.g., for x-ray contrast agents) can improve predictions at the local scale without compromising regional exposure estimates. Pharmaceuticals that have low concentrations and are barely detectable with established analytical methods can be evaluated with model simulations. In addition, current management strategies implemented under the WFD has been replicated and evaluated. These management scenarios simulated with the model allow an a priori evaluation of risk reduction measures. In combination with targeted monitoring approaches, it was shown that the GREAT-ER model can serve as a valuable tool for exposure and risk assessment of pharmaceuticals even in challenging watersheds. This and the useful combination of targeted monitoring and GREAT-ER simulations and the ability of the modeling approach to predict the expected range of spatial surface water concentrations is demonstrated by three selected journal articles.
17

AN EXPLORATION OF POLICY IMPLEMENTATION IN PROTECTED WATERSHED AREAS: CASE STUDY OF DIGYA NATIONAL PARK IN THE VOLTA LAKE MARGINS IN GHANA

Ayivor, Jesse S. 17 April 2007 (has links)
No description available.
18

Dilemmas of regional governance : sub-national territorial politics and river basin management in the USA, France, China, and India

Moore, Scott Michael January 2013 (has links)
This dissertation identifies and explores the dilemma of regional governance, namely how to address political and economic challenges which occur at the meso-, as opposed to local, national, or international scale. Drawing on a large body of theoretical work on decentralization and federalism, this dissertation addresses the question, how do different institutional arrangements for political, fiscal, and administrative decentralization influence the capacity of political systems to capture regional-scale externalities? It does so by examining the responses of four different political systems, two federal and two unitary, to the problem of capturing economic externalities through River Basin Management (RBM), a quintessential regional issue. RBM outcomes are operationalized in terms of efficacy of capture of both water quality and quantity externalities which occur within inter-jurisdictional river basins. Through close historical analysis of six paired case studies across the four country cases, the dissertation argues that the capacity of political systems to capture regional-scale externalities depends on the ability of sub-national jurisdictions to pursue localized preferences, which is in this dissertation referred to as sub-national territorial politics. These politics are most prevalent in federal systems, which typically accord sub-national territorial jurisdictions with greater political power and fiscal resources. These political systems feature fewer and weaker regional governance institutions, and generally less effective regional-scale externality capture, than their counterparts. This dissertation contributes to a growing "sub-national turn" in comparative politics in two ways. First, it identifies the geographically-rooted interests which often shape sub-national actor preferences, particularly with respect to natural resource issues. Second, the dissertation discerns the lack of political incentives for central governments to resolve disputes between sub-national administrative jurisdictions, particularly in the federal systems in which these units are the basis for political representation at the national level.
19

Právní úprava ochrany vodních toků / Legal regulation of watersourse protection

Altmann, Martin January 2019 (has links)
Thesis title: Legal regulation of watercourse protection Abstract Watercourses are the most important form of surface water occurrence in the Czech Republic, and therefore their condition also significantly affects the overall state of all our aquatic ecosystems. Despite of it, the ecological and chemical status of watercourses is still not satisfying. This fact requires an increase in the efficiency and complexity of their legal protection, which is the subject of this thesis. The aim of the first part of this thesis is to describe the national legal regulation of watercourses protection in the context of European and international law. At present, national and international legislation is significantly influenced by European legislation provided by the Water Framework Directive. The first part pays attention to the instruments of national legislation, that are relevant to the second part of the work. The first aim of the second part of this thesis is to analyse the basic measures proposed in the two selected sub-basins in order to achieve the objectives of the Water Framework Directive, particularly the good water status. Following this analysis, the second aim is to find out what specific instruments the current legislation provides for the realization of the proposed measures and whether these...
20

Estimativa da erosão hídrica nas bacias hidrográficas dos rios Lontra e Manuel Alves Pequeno, TO

Barros, Enicléia Nunes de Sousa 25 March 2017 (has links)
A erosão hídrica constitui um dos principais processos de degradação do solo, com impactos que vão desde a redução da produtividade até a diminuição dos recursos naturais existentes. Nesse sentido, o presente trabalho objetivou avaliar o efeito das alterações no uso do solo, de 1990 a 2007, aplicando o modelo RUSLE para estimar espacialmente o comportamento da erosão do solo para as bacias hidrográficas dos rios Lontra e Manuel Alves Pequeno-TO. A erosão hídrica na bacia do rio Lontra, no ano de 2007, variou de “suave” (51,3%), na região central da bacia, onde o relevo é plano e o uso do solo predominante é mata nativa, a “extremamente alta” (24,6%), na faixa que vai do norte ao oeste, com uso do solo predominante pela pecuária e relevo mais declivoso. Na bacia do rio Manuel Alves pequeno, no mesmo período, a classe de erosão denominada suave” (52%) está distribuída ao longo da bacia, devido à maior parte dos solos apresentar baixa erodibilidade e com a maior parte da área cobertas pelo cerrado, já a classe “extremamente alta” (6,7%), nas porções norte e oeste ocorreu devido ao uso do solo pela pecuária, e na porção leste devido à maior declividade. A avaliação temporal da perda de solo evidenciou que não houve variações significativas no período estudado, contudo, na bacia do rio Lontra, de 2000 a 2007, ocorreu uma redução 0,3% da classe “extremamente alta”, devido ao avanço do cerrado sobre a pecuária, enquanto que na bacia do rio Manuel Alves Pequeno, de 1990 a 2007, houve o aumento gradual da taxa de erosão, com a soma das classes “alta”, “muito alta” e “extremamente alta” passando de 25% para 26,4%, justificado pelo crescimento das atividades pastoris nessa bacia. Os pontos críticos de maior susceptibilidades à erosão, encontrados nesse trabalho, constituem-se ferramentas fundamentais para a tomada de decisões associadas ao manejo, conservação e planejamento do uso do solo. / The hydraulic erosion is one of the main processes of soil degradation. It brings about impacts which range from productivity reduction to existing natural resources decrease. This way, the present work had the objective to evaluate the effects of the alternations in soil use from 1990 to 2007, applying RUSLE model to estimate the soil erosion behavior in space to the hydrographic basins of the Lontra River and Manuel Alves Pequeno River – TO. The hydraulic erosion of the Lontra River basin in 2007 ranged from “light” (51,3%), in the basin central region, where the land is flat and the predominant soil is native wood, to “extremely high” (24,6%) from north to west with land use predominantly by livestock and bending soil surface. In the Manuel Alves Pequeno River basin, in the same period, the erosion classified as “light” (52%) is distributed along the basin, due to most of the soil presents low erosion properties and most of the land is covered by cerrado. As for the “extremely high” (6,7%) in the north and west, it occurred due to the land being used by livestock and in the east, due to being more bending. The seasonal evaluation of the soil loss evidenced that there were no significant variations while carrying out these studies. However, in the Lontra River basin, from 2000 to 2007, there was a reduction of 0,3% in the “extremely high” class due to the advance of the cerrado over the cattle ranch, while in the Manuel Alves Pequeno River basin, from 1990 to 2007, there was a gradual increase on the erosion level, with the addition of the “high”, “very high” and “extremely high” classes, ranging from 25% to 26,4%, explained by the growth of pastoral activities in this basin. The critical points with higher soil susceptibility to erosion, found in this work, become fundamental tools to make decisions associated to the management preservation and planning the soil use.

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