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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

Considering Climate Change Through Global Water Initiatives

Haverland, Arin C. January 2015 (has links)
Hundreds of international water institutions have been established over the last three decades in an attempt to address global water issues. Despite great efforts by these and other institutions, a significant percentage of the world's population still lacks access to clean water and sanitation facilities. Although billions of dollars have been spent on development, infrastructure and public health endeavors meant to tackle such issues, little research has been done to examine how these often influential organizations known as global water initiatives (GWIs) are addressing such urgent issues in the face of a rapidly changing climate. As water is central to the hydrological cycle, and affected by changes in climate, examining the role of GWIs in the use and translation of climate-change science may lead to better understanding of the mechanisms through which such organizations are linking climate change to their work in water management and governance. By examining 170 GWIs through two distinct phases of methodology, it was found that GWIs are addressing climate change issues through their work with water. Evidence presented in this research supports the claim that GWIs have adopted climate change as part of their overall operational frameworks and that their missions may be supported and ultimately achieved through the addition of climate-change science. While GWIs are shown to use climate-change science in setting objectives, and in decision making, it was also found that issues of cost, access, and utility remain as significant barriers. Findings presented in this study also suggest that intergovernmental and nongovernmental organizations, alongside professional societies dedicated to trades and disciplines related to water, are among the most important categories of GWIs, and as such, operate within a series of complex networks. This research also revealed that activities and outputs of GWIs enhance water management and governance, contribute to the world's knowledge base on water, and highlight the need to acknowledge GWIs as an important and prominent aspect of the global water dialogue.
102

The Use of Traditional Environmental Knowledge to Assess the Impact of Climate Change on Subsistence Fishing in the James Bay Region, Ontario, Canada

Hori, Yukari 17 May 2010 (has links)
This thesis used traditional environmental knowledge (TEK) to assess the impacts of climate change on food security for First Nations communities located in the western James Bay region of northern Ontario. In addition, climate scenarios were derived from General Circulation Models (GCMs) and Regional Climate Models (RCMs). The TEK data revealed there were no observable climatic-related effects on fish species (i.e., distributional change) except the fish die-offs of July 2005. Climate data specific for the period of the fish die-offs in the Albany River (the western James Bay region) indicated not only a temporal relationship between a heat wave and the fish die-offs, but also a concurrent period of reduced precipitation. Climate scenarios showed increases in mean air temperature for all seasons, all time periods (2011– 2040, 2041– 2070, and 2071– 2100), and all emission scenarios (A2, A1B, and B1); however, the results for seasonal total precipitation were variable, dependent emission scenarios. TEK suggest that increasing temperatures may not be the only climate change phenomena of importance; climate variability and extreme events were reported as precipitating fish die-offs and changes in the timing of harvesting of fish. Further research should concentrate on the investigation of climate change and food security issues in sub-arctic regions.
103

An Evaluation of the Reintroduction of Atlantic Salmon to Lake Ontario and its Tributaries

Glass, Carolyn January 2010 (has links)
As the field of restoration continues to develop, it is important that initiatives are evaluated for their effectiveness and to explore the motivations and justifications behind the projects‘ designs. Current restoration ecology seeks to orient projects toward the future instead of rooting them in the past. By focusing on ecosystem function rather than specific species composition, the needs of the current ecosystem are better able to be addressed. The dynamic and complex nature of ecosystems means restoration ecologists must have a firm understanding of current conditions and design several trajectories for restoration projects. Not all current restoration projects adhere to this more recent framework, and many fall short of achieving goals set by international organizations, such as the Society for Ecological Restoration. The Atlantic Salmon Reintroduction Program for Lake Ontario began in 2006 with the goal of establishing a self sustaining Atlantic salmon population in Lake Ontario. Over 30 organizations have joined together to implement this program which involves fish production, habitat restoration, monitoring and assessment as well as education and outreach. Though some success has been achieved through habitat projects and observation of some returning adults, the future of the project is still being evaluated. By reviewing relevant literature and conducting interviews with key partners, the program was evaluated for its adherence to restoration principles and the following areas were used to evaluate its success. These broad themes included: (1) the biological interactions of these fish with their surroundings; (2) the history of the ecosystem; (3) the influence of humans on the restoration process; (4) the value laden aspect of the iv process; and (5) the extent of a ―systems‖ approach. The justification for this program appears to be based more on culture, aesthetic and economic value than sound ecological science but, as all respondents agreed, the ability of Lake Ontario to support a healthy, self-sustaining population of Atlantic salmon would be a good indicator of overall ecosystem health at least in terms of water quality and quantity. Despite this potential achievement, reintroducing a single extirpated species while focusing solely on its habitat and survival, fails to address the multitude of concerns within the Lake Ontario watershed. Consequently this reintroduction limits the potential for restoration of the Lake and is far less efficient and effective than had other opportunities been pursued.
104

Managing Groundwater for Environmental Stream Temperature

Buck, Christina Rene 15 August 2013 (has links)
<p> This research explores the benefits of conjunctively managed surface and groundwater resources in a volcanic aquifer system to reduce stream temperatures while valuing agricultural deliveries. The example problem involves advancing the understanding of flows, stream temperature, and groundwater dynamics in the Shasta Valley of Northern California. Three levels of interaction are explored from field data, to regional simulation, to regional management optimization. Stream temperature processes are explored using Distributed Temperature Sensing (DTS) data from the Shasta River and recalibrating an existing physically-based flow and temperature model of the Shasta River. DTS technology can collect abundant high resolution river temperature data over space and time to improve development and performance of modeled river temperatures. These data also identify and quantify thermal variability of micro-habitat that temperature modeling and standard temperature sampling do not capture. This helps bracket uncertainty of daily temperature variation in reaches, pools, side channels, and from cool or warm surface or subsurface inflows. The application highlights the influence of air temperature on stream temperatures, and indicates that physically-based numerical temperature models, using a heat balance approach as opposed to statistical models, may under-represent this important stream temperature driver. The utility of DTS to improve model performance and detailed evaluation of hydrologic processes is demonstrated. </p><p> Second, development and calibration of a numerical groundwater model of the Pluto's Cave basalt aquifer and Parks Creek valley area in the eastern portion of Shasta Valley helps quantify and organize the current conceptual model of this Cascade fracture flow dominated aquifer. Model development provides insight on system dynamics, helps identify important and influential components of the system, and highlights additional data needs. The objective of this model development is to reasonably represent regional groundwater flow and to explore the connection between Mount Shasta recharge, pumping, and Big Springs flow. The model organizes and incorporates available data from a wide variety of sources and presents approaches to quantify the major flow paths and fluxes. Major water balance components are estimated for 2008-2011. Sensitivity analysis assesses the degree to which uncertainty in boundary flow affects model results, particularly spring flow. </p><p> Finally, this work uses optimization to explore coordinated hourly surface and groundwater operations to benefit Shasta River stream temperatures upstream of its confluence with Parks Creek. The management strategy coordinates reservoir releases and diversions to irrigated pasture adjacent to the river and it supplements river flows with pumped cool groundwater from a nearby well. A basic problem formulation is presented with results, sensitivity analysis, and insights. The problem is also formulated for the Shasta River application. Optimized results for a week in July suggest daily maximum and minimum stream temperatures can be reduced with strategic operation of the water supply portfolio. These temperature benefits nevertheless have significant costs from reduced irrigation diversions. Increased irrigation efficiency would reduce warm tail water discharges to the river instead of reducing diversions. With increased efficiency, diversions increase and shortage costs decrease. Tradeoffs and sensitivity of model inputs are explored and results discussed.</p>
105

An Innovative MultiVariable Control Framework for Effective Wireless Resource Management

Liu, Chen Unknown Date
No description available.
106

The impact of supply-side human resource issues on organizations : an examination of a temporary accountancy firm

Albert, Steven Brian January 1993 (has links)
The preferences of individuals over working conditions may have profound effects on organizations and labour markets, and yet their impact has, for the most part, been marganalized. We argue that, in light of evolutionary developments in the workplace, a re-thinking of the impact of supply-side influences on specific labour market segments and organizations is called for. To this end, this study evaluates contemporary human resource issues, specifically - preferences of individuals to control working-time and the impact this may have on labour market segmentation theory and organizations. An analysis of data on such things as demographics, technology, payment systems and ethical views suggests an environment conducive for a more time-sensitive employee. We hypothesize that this time-sensitive employee may search for an organization, like the temporary agency, which provides the control over working-time that they prefer. Thus forming a unique supply-side driven labour market segment. We also assert that job forms like this, rather than being a peripheral secondary level job form, may be forming a new labour market segment that is neither primary nor secondary just atypical. Our hypotheses are derived from an approach that focuses on supply-side rather than demand-side influences, and a new adaptation and application of a more general time-sensitive model. We tested our hypotheses using a three tiered approach: (i) a secondary analysis of past data sets, (ii) analysis based upon our interviews with 17 managers from London temporary accountancy agencies and (iii) our own data set drawn from 175 employees of a Large London accountancy firm and 50 employees of a London temporary accountancy agency. We found that temporary agency employment when compared to large firm employment was associated with greater control over working-time and was associated with employees who exhibited a greater preference for control over working-time. Therefore, we found evidence for supply-side driven job-form choice. We also found that those employees related to the internal labour market's "core" exhibited a preference for control over working-time and received control over working-time in their compensation packages.
107

The mechanism(s) underlying the antiarrhythmic effect of drugs acting on endothelin receptors in myocardial ischaemia and reperfusion

Crockett, Thomas Robert January 2002 (has links)
No description available.
108

An overview of natural resources managment in Murang'a District, Kenya

Kabaru, Emma January 1986 (has links)
This study examined the extent of natural resources management in one of the most densely populated districts in Kenya. The nature of land use, land ownership structure, and natural resource management strategies were examined. A theoretical assessment of the natural resources potential was conducted and the relationship between population and land resources was addressed. possible causes of the major problems in natural resources conservation and development were examined. In addition, possible implications of these problems and opportunities for securing a self-sustaining environment were studied. The approach followed was partly systematic based on the existing data sources, and partly conceptual, based on intuition and observation of some of the significant factors. The principle methods used were a review of the literature, supplemented with a reconnaissance field trip to the area, communication with people knowledgeable of the area, and the author's own experience and observations. The study indicated that the traditional practices of natural resources management have been disrupted by the adoption of a more intensive system of land tenure, and other political, social and economic factors. Two main recommendations were proposed: (1) that a viable development strategy to increase income earning opportunities through the utilization of existing natural resources and local labour resources be adopted, and (2) that top priority be given to addressing the problems of resource conservation and utilization in Murang'a district.
109

The effects of effluent discharge and concentration on streambed infiltration in the Lower Santa Cruz River

Prietto, Jacob 21 October 2014 (has links)
<p> Wastewater generated in the Tucson metropolitan region is conveyed to and treated at the Roger Road Wastewater Reclamation Facility (WRF) and Ina Road WRF. From 2005 to 2012, approximately 15,000 acre-feet per year of effluent was returned to the City of Tucson for additional filtration and reuse in the reclaimed water system. The remaining 48,000+ acre-feet per year of treated effluent was discharged to the Santa Cruz River, where a variable portion of the effluent infiltrates the streambed. The effluent that infiltrates the streambed contributes to recharge credits for participants invested in the Managed Underground Storage Facilities.</p><p> In the effluent-dependent river, physical, chemical, and biological processes work in combination to develop a clogging layer near the streambed surface, which reduces infiltration. Previous studies have shown that large storm events have the ability to scour away the clogging layer and are the most significant processes contributing to establishing infiltration rates. Without the occurrence of large storm events, other variables such as effluent discharge and effluent concentrations affect infiltration to a lesser degree.</p><p> Effluent discharge, biochemical oxygen demand, and total suspended solids are monitored and recorded daily at the outfalls of the WRFs. The parameters were investigated individually and in combination using statistical analyses to determine their correlations with streambed infiltration in the Santa Cruz River. The dry spring-early summer seasons from 2005 to 2012 were analyzed. A water balance was constructed for non-stormflow days during each time period. Evapotranspiration was calculated using riparian vegetation surveys and detailed delineations of aerial photography of the surface water and streamside herbaceous vegetation. Infiltration was derived as the residual of the water balance. </p><p> At the daily time scale, correlations among variables were unobtainable due to the extremely variable characteristics of infiltration. The seasonal time scale analyses demonstrated an inverse relationship between both the effluent concentrations of biochemical oxygen demand and total suspended solids with infiltration and a direct correlation between effluent discharge and infiltration under extreme conditions. Under normal conditions, the distribution of discharge between Roger Road WRF and Ina Road WRF had a critical effect on infiltration as a result of the different deposition and erosive regimes through the Santa Cruz River.</p>
110

Shaping the frontier : farmers' organisations and the environment in eastern Amazonia

Muchagata, Marcia Regina Goncalves January 2002 (has links)
No description available.

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