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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.
211

Institutional overlaps in water management in the Eerste River catchment

Nleya, Ndodana January 2005 (has links)
Magister Philosophiae (Integrated Water Resource Management) / In this minithesis I have investigated overlapping mandates as a source of management failure in water management in South Africa in general and Eerste River Catchment in particular. I analysed major legislation which deals with water management to find out how duties and responsibilities are apportioned in the various pieces of legislation. I also undertook an exercise of evaluating roles and responsibilities played by various organs of state in water management from national government, Provincial Government of the Western Cape through to local government, in this case the Municipality of Stellenbosch and the City of Cape Town. It emerged that there were a number of areas of overlap, ambiguously defined mandates, conflict and that these were impeding on decision making in water management. In order to test the framework built above, I then applied it in the Plankenbrug River, a tributary of the Eerste River. Through analysis of newspaper clippings over a period of 4 years I was able to reconstruct conflict over ill-defined mandates in the various aspects of the management of the catchment which showed that there were differences in roles of the different state organs operating in the catchment. Water management conflict emanated from lack of congruence in the various legislation and differences in the interpretation of legislation. The various state organs seem to be aware of the constitutional duty of cooperative government that engenders state organs to work co-operatively in order to meet their developmental mandates. It seems however that the state organs were merely interested to be seen to be in conformity with this duty more than actually solving the issue as this was seen as something to be tackled at a higher level. / South Africa
212

Process-Based Calibration of WRF-Hydro Model in Unregulated Mountainous Basin in Central Arizona

January 2020 (has links)
abstract: The National Oceanic and Atmospheric Administration (NOAA)’s National Water Model (NWM) will provide the next generation of operational streamflow forecasts at different lead times across United States using the Weather Research and Forecasting (WRF)-Hydro hydrologic system. These forecasts are crucial for flood protection agencies and water utilities, including the Salt River Project (SRP). The main goal of this study is to calibrate WRF-Hydro in the Oak Creek Basin (OCB; ~820 km2), an unregulated mountain sub-watershed of the Salt and Verde River basins in Central Arizona, whose water resources are managed by SRP and crucial for the Phoenix Metropolitan area. As in the NWM, WRF-Hydro was set up at 1-km (250-m) resolution for the computation of the rainfall-runoff (routing) processes. Model forcings were obtained by bias correcting meteorological data from the North American Land Data Assimilation System-2 (NLDAS-2). A manual calibration approach was designed that targets, in sequence, the sets of model parameters controlling four main processes responsible for streamflow and flood generation in the OCB. After a first calibration effort, it was found that WRF-Hydro is able to simulate runoff generated after snowmelt and baseflow, as well as magnitude and timing of flood peaks due to winter storms. However, the model underestimates the magnitude of flood peaks caused by summer thunderstorms, likely because these storms are not captured by NLDAS-2. To circumvent this, a seasonal modification of soil parameters was adopted. When doing so, acceptable model performances were obtained during calibration (2008-2011) and validation (2012-2017) periods (NSE > 0.62 and RMSE = ~2.5 m3/s at the daily time scale). The process-based calibration strategy utilized in this work provides a new approach to identify areas of structural improvement for WRF-Hydro and the NWM. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2020
213

Internal Stresses and Social Feedback Mechanisms in Social-Ecological Systems: A Multi-Method Approach to the Effectiveness of Exit and Voice

January 2020 (has links)
abstract: My research is motivated by a rule of thumb that no matter how well a system is designed, some actors fail to fulfill the behavior which is needed to sustain the system. Examples of misbehavior are shirking, rule infraction, and free riding. With a focus on social-ecological systems, this thesis explored the effectiveness of social feedback mechanisms driven by the two available individual options: the exit option is defined as any response to escape from an objectionable state of affairs; and the voice option as any attempt to stay put and improve the state. Using a stylized dynamic model, the first study investigates how the coexistence of participatory and groundwater market institutions affects government-managed irrigation systems. My findings suggest that patterns of bureaucratic reactions to exit (using private tubewells) and voice (putting pressure on irrigation bureaus) are critical to shaping system dynamics. I also found that the silence option – neither exit nor voice – can impede a further improvement in public infrastructure, but in some cases, can improve public infrastructure dramatically. Using a qualitative comparative analysis of 30 self-governing fishing groups in South Korea, the second study examines how resource mobility, group size, and Ostrom’s Design Principles for rule enforcement can co-determine the effectiveness of the voice option in self-controlling rule infractions. Results suggest that the informal mechanism for conflict resolution is a necessary condition for successful self-governance of local fisheries and that even if rules for monitoring and graduated sanctions are not in use, groups can be successful when they harvest only stationary resources. Using an agent-based model of public good provision, the third study explores under what socioeconomic conditions the exit option – neither producing nor consuming collective benefits – can work effectively to enhance levels of cooperation. The model results suggest that the exit option contributes to the spread of cooperators in mid- and large-size groups at the moderate level of exit payoff, given that group interaction occurs to increase the number of cooperators. / Dissertation/Thesis / Doctoral Dissertation Environmental Social Science 2020
214

A new integrated modeling approach to support management decisions of water resources systems under multiple uncertainties

Subagadis, Yohannes Hagos 15 September 2015 (has links)
The planning and implementation of effective water resources management strategies need an assessment of multiple (physical, environmental, and socio-economic) issues, and often requires new research in which knowledge of diverse disciplines are combined in a unified methodological and operational framework. Such integrative research to link different knowledge domains faces several practical challenges. The complexities are further compounded by multiple actors frequently with conflicting interests and multiple uncertainties about the consequences of potential management decisions. This thesis aims to overcome some of these challenges, and to demonstrate how new modeling approaches can provide successful integrative water resources research. It focuses on the development of new integrated modeling approaches which allow integration of not only physical processes but also socio-economic and environmental issues and uncertainties inherent in water resources systems. To achieve this goal, two new approaches are developed in this thesis. At first, a Bayesian network (BN)-based decision support tool is developed to conceptualize hydrological and socio-economic interaction for supporting management decisions of coupled groundwater-agricultural systems. The method demonstrates the value of combining different commonly used integrated modeling approaches. Coupled component models are applied to simulate the nonlinearity and feedbacks of strongly interacting groundwater-agricultural hydrosystems. Afterwards, a BN is used to integrate the coupled component model results with empirical knowledge and stakeholder inputs. In the second part of this thesis, a fuzzy-stochastic multiple criteria decision analysis tool is developed to systematically quantify both probabilistic and fuzzy uncertainties associated with complex hydrosystems management. It integrates physical process-based models, fuzzy logic, expert involvement and stochastic simulation within a general framework. Subsequently, the proposed new approaches are applied to a water-scarce coastal arid region water management problem in northern Oman, where saltwater intrusion into a coastal aquifer due to excessive groundwater extraction for irrigated agriculture has affected the aquifer sustainability, endangering associated socio-economic conditions as well as traditional social structures. The results show the effectiveness of the proposed methods. The first method can aid in the impact assessment of alternative management interventions on sustainability of aquifer systems while accounting for economic (agriculture) and societal interests (employment in agricultural sector) in the study area. Results from the second method have provided key decision alternatives which can serve as a platform for negotiation and further exploration. In addition, this approach suits to systematically quantify both probabilistic and fuzzy uncertainties associated with the decision problem. The new approaches can be applied to address the complexities and uncertainties inherent in water resource systems to support management decisions, while serving as a platform for stakeholder participation.
215

Institutional challenges in integrated water resources management in Zimbabwe: a case study of the Pungwe sub-catchment area

Tapela, Barbara Nompumelelo January 2002 (has links)
Magister Philosophiae - MPhil / Integrated Water Resources Management (IWRM) is viewed by policy makers and practitioners as facilitating the achievement of a balance between water resources use and protection, and the resolution of water-related conflicts. The IWRM approach has found particular use in the new water policies of Southern African countries such as Zimbabwe, where water scarcity, after the land question, is perceived to be a major threat to political, economic, social, military and environmental security. Ultimately, IWRM is seen as providing a framework towards ensuring broader security at the local, national, regional and global levels. However, the pilot phase implementation of the new water policy in the various regional countries has revealed that although the legal and institutional frameworks have been put in place, the implementation of the IWRM approach has tended to be problematic (Latham, 2001; GTZ, 2000; Leestemaker, 2000; Savenige & van der Zaag, 2000; Sithole, 2000). This study adopts a case study approach and empirically examines the institutional challenges of implementing the IWRM approach in the post-pilot phase of Zimbabwe's new water policy. The focus is mainly on the institutional arrangements surrounding the Pungwe-Mutare Water Supply Project located within the Save Catchment Area in Eastern Zimbabwe. The major finding of the study is that, while there are some problems associated with the traditional management approach, there have also emerged new challenges to IWRM. These mainly relate to the transaction costs of the water sector reforms, institutional resilience, stakeholder participation, and the achievement of the desired outcomes. There have also been problems emanating from unexpected political developments at the local and national levels, particularly with regard to the government's "fast track" land resettlement programme. The study also raises some questions concerning the ideological bases of IWRM and the conceptualization of the institutional problem.
216

Resilience Thinking For Common Pool Resources Management - Avoiding Drought Induced Disaster Threats in Indian Rajasthan.

Sultanem, Nicolas January 2016 (has links)
Drought related problems are a major stress source on the livelihood of communities in several areas of the world. Due to inefficient water resources management people leave their traditional habitat in search for security in larger agglomerations. This creates a big stress on the carrying capacity of urban centers and leaves deserted rural areas incapacitated. Setting Sustainable Development Goals as targets to reach, using Resilience Thinking to provide for resilience, adaptability and transformability, and planning for Integrated Water Resources Management can be a solution to reduce this outmigration. Rajasthan is a state in India where communities have been surviving with very little available water for ages. Contemporaneous implementations in parts of Rajasthan fulfill the framework set for this study. After identifying a promising SES in terms of drought resilience a field investigation was conducted for adequate assessment and model of resilient SES was reverse engineered from the findings. Reading thru this document one can explore the uniqueness of Rajasthan water governance from pasts long gone and to the current date. In the end of the study strategic adaptive planning recommendations can be found for creating a similar SES.
217

Re-(Framing) Uncertainties in Water Management Practice

Isendahl, Nicola 25 June 2010 (has links)
Management of water resources is afflicted with uncertainties. Nowadays it is facing more and new uncertainties since pace and dimension of changes (e.g. climatic, demographic) are accelerating and are likely to increase even more in the future. Hence it is crucial to find pragmatic ways to deal with these uncertainties in water management. This thesis argues for an analytical yet pragmatic approach to enable decision-makers to deal with uncertainties in a more explicit and systematic way and allow for better informed decisions. The approach is based on the concept of framing and mental models, referring to different ways in which people make sense of the world and of uncertainties. It is analysed how uncertainties are framed and dealt with in water management practice and strategies are elaborated how dealing with uncertainties can be improved in water management practice. The research for this thesis has been closely linked to the EU research project NeWater (New Approaches to Adaptive Water Management under Uncertainty, www.newater.uos.de) (2005-2009). It draws on practical experiences of water managers at local and regional level in river basin management in three case studies, i.e. the German Wupper, the Dutch Kromme Rijn, both sub basins of the river Rhine, and the Doñana region located in the Guadalquivir Estuary in Spain. For the assessment of framing of uncertainty two different methods were developed and applied in the three river basins. Both aim at identifying parameters of importance in the process of framing uncertainty in order to understand how uncertainties get framed. The empirical research confirmed that indeed water managers are faced with a range of uncertainties and that so far no systematic approaches are applied for dealing with those in management practice. The results in the case studies suggest that there are no universal findings as to how actors frame uncertainties but rather that framings are dependent on the respective uncertainty situation, on roles (e.g. project leader, public administration, scientist etc.), and most often on personal traits. The case study findings moreover suggest that there are no universally valid parameters of influence in the framing of uncertainties. Neither could a clear superiority of one approach over the other be discerned. Nonetheless, the parameters of framing of uncertainty proved to be a supportive tool for preparing and structuring decision-making in the case studies and developing improvement options for dealing with uncertainty. Beyond the results of the development of approaches for the assessment of framing of uncertainty in water management practice, processes of communication and learning turned out to be of major importance. Making framings of uncertainties explicit by help of parameters of framing proved to be useful in the case studies for revealing different points of views on the uncertainties and with regard to the strategies to deal with them. This is a first step in enabling dialogue among opposed framers and an important precondition for reframing and learning which is crucial for the long-term performance in management of natural resources.
218

Ultrasonic Flow Measurement for Pipe Installations with Non-Ideal Conditions

Stoker, Devin M. 01 December 2011 (has links)
In the arid west, water is among the most valuable of resources. Typically, in order to successfully and accurately measure a flow rate using most types of flow meters, it is recommended that a straight section of pipe be installed immediately upstream from the flow meter to avoid distorted flow patterns and extreme turbulence at the metering location. In many field piping situations, however, such flow conditions are impossible to achieve. The performance of ultrasonic flow meters in non-ideal piping scenarios was studied using laboratory experiments and numerical Computational Fluid Dynamics models. A Fuji PortaflowX clamp-on transit-time ultrasonic flow meter was calibrated in the laboratory and performed well within the manufacturer’s stated level of accuracy of ±1% for straight pipe. The ultrasonic flow meter was also used downstream of a single 12-inch long-radius elbow and the error in flow measurement resulting from the flow disturbance was measured. These tests were performed at four locations downstream of the elbow, at three orientations on the circumference of the pipe, and for three flow rates with Reynolds numbers ranging from 250,000 to 750,000. Using the same physical conditions, numerical models were built that utilized the realizable k-ε eddy viscosity model for turbulent flows. The resulting downstream velocity profiles from the numerical models were used to integrate the velocity of the flow across the ultrasonic signal path. The resulting velocity profiles were compared to similar profiles for fully developed flow to determine the error in flow measurement. The ultrasonic flow meter measurement errors downstream of the elbow were always negative, and were found to be as great as -16%. In general, the ultrasonic flow meter performed less accurately closer to the elbow due to the turbulent fluctuations and flow separation created by the elbow. A correction curve was applied to the results of this study, which provided a method to correct the ultrasonic flow measurement. By applying the correction equation to the laboratory ultrasonic flow meter measurements downstream of the elbow, the measurement error was reduced by nearly 90%. Computational Fluid Dynamics appears to be a viable tool for studying flow disturbances and making appropriate corrections for ultrasonic flow measurement in pipes.
219

Institutions for Provision of Shared Infrastructure: Insights from Irrigation Systems in India

January 2019 (has links)
abstract: In many social-ecological systems, shared resources play a critical role in supporting the livelihoods of rural populations. Physical infrastructure enables resource access and reduces the variability of resource supply. In order for the infrastructure to remain functional, institutions must incentivize individuals to engage in provision and maintenance. The objective of my dissertation is to understand key formal and informal institutions that affect provision of shared infrastructure and the policy tools that may improve infrastructure provision. I examine these questions in the context of irrigation systems in India because infrastructure maintenance is a persistent challenge and system function is critical for global food production. My first study investigates how the presence of private infrastructure, such as groundwater pumps, affects the provision of shared infrastructure, such as shared tanks or surface reservoirs. I examine whether formal institutions, such as water pricing instruments, may prevent under-provision of the shared tanks. My findings suggest that in the absence of rules that coordinate tank maintenance, the presence of private pumps will have a detrimental effect on system productivity and equality. On the other hand, the combination of a fixed groundwater fee and a location-based maintenance fee for tank users can improve system productivity and equality. The second study examines the effect of power asymmetries between farmers, caused by informal institutions such as caste, on the persistence of political institutions that govern infrastructure provision. I examined the effect of policy tools, such as non-farm wage employment and informational interventions, on the persistence of two types of political institutions: self-governed and nested. Results suggest that critical regime shifts in political institutions can be generated by either intervening in formal institutions, such as non-farm wage employment, or informal institutions, such as knowledge transmission or learning mechanisms. The third study investigates how bureaucratic and political corruption affect public good provision. I examine how institutional and environmental factors affect the likelihood of corruption and infrastructure provision. I demonstrate that cracking down on corruption is only beneficial when infrastructure provision is poor. I also show that bureaucratic wages play an important role in curbing extralegal transactions and improving infrastructure provision. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2019
220

IMPACT OF RAPID DEVELOPMENT GROWTH ON WATER RESOURCES SITUATION IN TOURISM DEPENDENT ECONOMY : A CASE STUDY OF BALI, INDONESIA / 観光依存経済圈における高度成長が水資源状況に及ぼす影響 : インドネシア国バリ島を対象に

Eva, Mia Siska 26 March 2018 (has links)
付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21057号 / 工博第4421号 / 新制||工||1687(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 寶 馨, 教授 田中 茂信, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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