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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.
101

Climate change implications on transboundary water management in the Jordan River Basin : A Case Study of the Jordan River Basin and the transboundary agreements between riparians Israel, Palestine and Jordan

Young, Maisa January 2015 (has links)
The purpose of this thesis is to explore the relationship between the impacts of climate change and transboundary water management (TWM) mechanisms. The thesis does so through a case study of the transboundary water agreements between Israel, Palestine and Jordan – states that share the transboundary waters in the Jordan River Basin (JRB), a basin that lies in a region of high political tensions and decreasing precipitation. By using empirical climate data on precipitation, temperature and general climate change projections for the basin, the author seeks to understand how these environmental changes will challenge TWM in the JRB. By using qualitative methods to examine the water agreements through the method of process tracing, the thesis seeks to understand how the water agreements are constructed to handle changes in waterflow due to climate change. The results show that the transboundary mechanisms, the water agreements and Joint Water Committees (JWC), managing the transboundary waters in the JRB, possess weak mechanisms to manage changes in waterflow. As a consequence, the whole basin might experience increasing political pressures in the future over the fulfilment of water allocation provisions. The thesis further suggests that the TWM structures in the case lack awareness and mechanisms to handle climate change impacts. On the other hand, the JWCs have an institutional capacity, expertise, and mandate in managing these potential risks in the future. However, incidents in the past, manifest that decreased waterflow leads to increasing political tensions and conflicts between the states in the basin due to the lack of conflict resolution mechanisms in the TWM structures. In order to establish a sustainable TWM in the JRB, the suggested recommendation is that climate change impacts ought to be embedded into the water agreements by incorporating flexible mechanisms for water allocation. In addition, the conflict resolution mechanisms should be strengthened.
102

Relationship Between Recharge, Redox Conditions, and Microbial Methane Generation in Coal Beds

Ritter, Daniel James January 2015 (has links)
Natural gas is an important transitional energy source to replace more carbon intensive coal combustion in the face of climate change and increasing global energy demands. A significant proportion of natural gas reserves (~20%) were recently generated by microorganisms that degrade organic-rich formations (i.e. coal, shale, oil) in-situ to produce methane. Recent studies have shown that these microbial communities may be potentially stimulated to generate more methane to extend the lifetime (~10 years) of existing biogenic gas wells. This dissertation investigates how microbial coalbed methane (CBM) systems are impacted by geochemical conditions, microbial community composition, and groundwater recharge. The first study is a review and synthesis of existing basic research and commercial activities on enhancement of microbial CBM generation, and identification of key knowledge gaps that need to be addressed to advance stimulation efforts. The second study couples water and gas geochemistry with characterization of microbial communities in coalbeds in the Powder River Basin (PRB), Wyoming to investigate the influence of microbiology on water and gas geochemistry. Geochemistry results indicated that nutrients are likely source in situ from coal, and that all sulfate must be removed from the system before methanogenesis will commence. Increased archaeal (i.e. methanogens) diversity was observed with decreasing sulfate concentration, while sulfate reducing bacterial communities were different in wells with high sulfate concentrations (sulfate reducing conditions) when compared to wells with low sulfate concentrations (methanogenic conditions). The third study uses noble gases to constrain the residence time of groundwater associated with CBM in the PRB. Measured diffusional release rates of 4He from PRB coals were ~800 times greater than typical rates observed in sandstone or carbonate aquifers, and measured 4He values far exceeded expected values from in-situ decay of U and Th. Groundwater 4He residence times ranged from <1 to ~800 years using the measured diffusion rates versus ~130 to 190,000 years using a standard model. Coal waters with the longest residence time had the highest alkalinity concentrations, suggesting greater extents of microbial methanogenesis, although there was no relationship between groundwater "age" and methane concentrations or isotopic indicators of methanogenesis. Constraining the relationship between microbial activity (e.g. mechanisms of coal biodegradation and methane generation), environmental geochemical conditions, and groundwater flow is important to better understand subsurface hydrobiogeochemical processes and to ensure the success of future projects related to stimulation of microbial CBM.
103

Simulating Groundwater Flow Through Methanogenic Coal Beds of the Tongue River Watershed

Randle, Nicholas Loring January 2014 (has links)
As an effort to gain a better understanding of the processes that enable and sustain coal bed methanogenesis in the western Powder River Basin, a steady-state groundwater flow model using MODFLOW 2005 was constructed. The model covers the middle Tongue River Watershed of north-central Wyoming and southeastern Montana and is comprised of five heterogeneous layers. The model is designed to determine the location of recharge and quantify the volume and velocity of groundwater fluxes to, from and within methanogenic coal beds. Analysis of the model's results indicate a groundwater regime dominated by horizontal flow, with little hydrologic connection between the methanogenic coal beds and the near-surface aquifers and streams. The model predicts only 3.88 cubic feet per seconds (cfs) or 2.17 percent of the total steady state flux within the modeled domain percolates downward to potentially reach the methanogenic coal beds. Most of this downward flux is predicted to occur at the base of the Bighorn Mountains. Additionally, the model predicts that the transit time to and resultant groundwater age within the methanogenic coal beds in the study area is on the order of thousands of years (predicted minimum age of 8,967 years).
104

Devilish straits: re-interpreting the source of Boundary Waters Treaty success

Wright, Graham 05 1900 (has links)
The Devils Lake defection of 2005 demands a re-evaluation of the venerable Boundary Waters Treaty (BWT) between Canada and the United States. Why was the long-successful water agreement unable to solve this relatively minor dispute? More importantly, given irregularities between theoretical assertions and institutional history, what theory of international relations best explains a cooperative agreement that spans a near-century? Due to the complexities of shared river systems, any theory that seeks to explain international cooperation must adequately encompass three separate sources of state motivation. First, it must explain the technical, basin-position-driven realities that affect state attitudes towards negotiations. Second, it must explain the longer-term strategic factors that can inspire states to accept immediate losses for subsequent gains. Finally, it must acknowledge domestic sources of influence and understand how these forces constrain the state vis-à-vis others. This paper argues that liberalism, as defined by Andrew Moravcsik, is the best theoretical candidate. This is proven by comparing interpretations of the BWT history through realist, neoliberal, constructivist, and liberal lenses. After identifying and examining each theory's strengths and weaknesses, liberalism emerges as the most holistic view and should be favoured as a primary explanatory theory. Liberalism's theoretical underpinnings – interest group politics – best handles the technical, strategic, and domestic influences that affect Canada-US water relations. Whether examining what prompted efforts to initiate a water-sharing agreement, explaining the agreement's final structure, determining the impetus for continued cooperation, or identifying the incentives to finally break from treaty obligations, liberalism provides the most satisfying solutions. Though derived from the Canada-US border relationship, liberalism's superiority is not limited to the North American watershed. Because the factors examined are common to all shared international river systems and the paper's results are scalable, this suggests that liberalism will continue to be the appropriate primary IR theory to employ when examining state decision-making regarding water-sharing agreements.
105

The influence of geomorphology and flow regulation on riparian cottonwoods

Willms, Chad Ryan, University of Lethbridge. Faculty of Arts and Science January 2005 (has links)
This study investigated the influence of geomorphic context and flow regulation on cottonwood (Populus) age structure, stand size, recruitment rates, and annual radial growth patterns along the Oldman River in southern Alberta. Dendrochronological techniques were used to age trees, establish population structures, and measure annual radial growth on three reaches in differing geomorphic contexts. Cottonwoods within a narrow, 'constrained' reach were more negatively impacted by partial dewatering of the river, but responded more favorably to increased late-summer flows combined with suitable recruitment conditions than the trees within a wide, 'alluvial' reach. A positive linear relationship between early-summer peak discharge and annual radial growth was found only on the alluvial reach. However, these trees also had the slowest growth rates, likely due to competition between trees because alluvial reaches often support large, dense stands of cottonwoods. This study demonstrates the need to consider the geomorphic context when studying cottonwood responses to river regulation. / xvi, 141 leaves : ill. ; 29 cm.
106

Modeling the Hydrology and Water Resources Management of South Saskatchewan River Basin under the Potential Combined Impacts of Climate Change and Climate Anomalies

Islam, Md. Zahidul Unknown Date
No description available.
107

Post- conflict peace building and natural resources: A comparative study on water management: Euphrates and Tigris River Basin in Northern and Western Iraq

Sofi, Galawesh January 2014 (has links)
Iraq has since post conflict of 2003 administrated the Euphrates and Tigris River in accordance to the countries plan management. It is researched in this study how the Iraqi Government and the Kurdistan Regional Government have managed and prioritized its water resource comparing the Euphrates and Tigris River flowing through Western and Northern Iraq. The focus is also on approaches and the alternative consequences derived from different management perspectives. It is concluded in this study that there are different priorities and management approaches in Iraqi Government and Kurdistan Regional Government. Iraqi Government has not managed Euphrates River as needed post conflict of 2003 where the approach is not satisfactory to resolve the problem facing the Euphrates River. It can become an underlying problem to an additional distress among the population which can heighten the risk for disputes and uprising of further conflicts in the region if the problems are not solved in Western Iraq. Tigris River that is also managed by the Iraqi Government has not been the top priority and there are unsolved problems around the river. The distress amongst the population can outburst in a bad manner if problems not solved surrounding the Tigris River. However the tributaries that flow through Kurdistan Regional Government to the Tigris River are of better condition more attention is directed to water management and there are aspirations for meeting the challenges and well as changing management approach. Kurdistan Regional Government has managed to prioritize and manage water from the tributaries better than Iraqi Government.
108

Mapping riparian vegetation functions using remote sensing and terrain analysis

Lymburner, Leo January 2005 (has links)
Land use practices over the last 200 years have dramatically altered the distribution and amount of riparian vegetation throughout many catchments in Australia. This has lead to a number of negative impacts including a decrease in water quality, an increase in sediment transport and a decrease in the quality of terrestrial and aquatic habitats. The task of restoring the functions of riparian zones is an enormous one and requires spatial and temporal prioritisation. An analysis of the existing and historical functions of riparian zones and their spatial distribution is a major aid to this process and will enable efficient use of remediation resources. The approach developed in this thesis combines remote sensing, field measurement and terrain analysis to describe the distribution of five riparian zone functions: sediment trapping, bank stabilization, denitrification, stream shading and large woody debris production throughout a large semi-arid catchment in central Queensland.
109

Effects of coalbed natural gas development on fish assemblages in tributary streams in the Powder River Basin, Montana and Wyoming

Davis, Windy Niccole. January 2008 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Alexander V. Zale. Includes bibliographical references (leaves 77-87).
110

Sage-grouse and energy development integrating science with conservation planning to reduce impacts /

Doherty, Kevin Eric. January 2008 (has links) (PDF)
Thesis (Ph.D.) -- University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on July 15, 2009. Includes bibliographical references.

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