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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.
31

Motivations and life satisfaction of participants in institutes for learning in retirement programs : Great Lakes Region

Garofolo, Patricia L. January 1995 (has links)
The purpose of this descriptive exploratory study was to investigate and report patterns of participation and motivational orientations of Institutes for Learning in Retirement (ILR)participants enrolled in ILR programs in the Great Lakes region. In addition, the study sought to identify relevant demographic characteristics for this segment of the population and the effects of ILR upon participation and participants' perceived life satisfaction.The Great Lakes region ILR participant profile was most likely to be female, between the ages of 66 and 70, married and living with spouse. She shared a relatively high economic status and extensive formal educational experience and was affiliated with her ILP program 1 to 2 years.Motives for ILR participation were examined using the Educational Participation Scale (EPS) A-Form (Boshier, 1991). Two influential motives for participation emerged. The first was "Cognitive Interest", the joy of learning for the sake of learning. "Social Contact," having an opportunity to meet new people and make friends, was the second major reason for participation.The perceived life satisfaction or subjective well being of ILR participants was explored using the Life Satisfaction Index A-Form (LSIA) (Neugarten, et al, 1961). Overall respondents revealed a perceived positive life satisfaction. Positive indications of well being include hopeful outlooks for the future, social interactions and sense of accomplishment.Results of this study indicate that the pursuit of intellectually stimulating adult educational programs offered within- a socially stimulating environment appeal to lifelong learners enrolled in Institutes for Learning in Retirement programs. This study supports the conclusion of previous investigators that intellectual stimulation is a strong underlying motivation for participation. The second major finding with regard to reasons for participation in ILR programs was the importance of "social contact." / Department of Educational Leadership
32

Great Lakes environmental policy : the ecosystem approach and an economic perspective

Jutlah, Russell Sean 11 1900 (has links)
This thesis is concerned with the conceptual foundations of environmental law and policy in the Great Lakes basin, the world's largest freshwater ecosystem. The Great Lakes regime is now widely recognized as one of the most advanced international environmental management regimes in existence. Over the past two decades, toxic contamination has emerged as a highly pressing ecological issue in the Great Lakes basin. In Canada and the United States, the ecosystem approach, a comprehensive and integrated approach to environmental management, has been adopted both bilaterally and domestically in the Great Lakes' complex environmental policy framework to guide the protection of ecological integrity. There has been extensive discussion of the ecosystem approach, particularly from scientific and managerial perspectives; however, the economic content of the concept has been largely neglected, despite the importance of considering all relevant perspectives in the development of law and policy. This thesis is divided into five chapters. After discussing in Chapter 1 the ecological and institutional contexts and methodological issues of the analysis, this thesis defends, in Chapter 2, the view that economic theory has relevance to issues of environmental law and policy. In addition to highlighting the main contours of welfare and environmental economic theory, a main conclusion, and an essential premise upon which the analysis proceeds, is that economics remains a useful analytical approach to environmental issues, despite some important criticisms. Subsequently, in Chapter 3, the analysis shifts to an examination of four bilateral and domestic Great Lakes instruments that form the core of Great Lakes toxic pollution policy: (i) the Great Lakes Water Quality Agreement; (ii) the Great Lakes Binational Toxics Strategy; (iii) the Canada-Ontario Agreement; and (iv) the Final Water Quality Guidance for the Great Lakes System. After outlining key principles underpinning each instrument, the thesis underscores common themes running through the collective policy framework. The ecosystem approach constitutes a unifying concept in this framework. The ecosystem approach is examined from an economic perspective in Chapter 4. After identifying key elements of the ecosystem approach, this chapter highlights important parallels between fundamental welfare and environmental economic notions. One main conclusion is that economic concepts and approaches, such as environmental valuation, externalities, and self-interest, form an integral part of the ecosystem approach. Finally, Chapter 5 identifies some directions for further research. Given that, as the thesis seeks to establish, economic theory constitutes an important, albeit not sole, perspective on the ecosystem approach, a key challenge will be to facilitate interdisciplinary analysis and cooperation leading to effective operationalization of the concept. / Law, Peter A. Allard School of / Graduate
33

Entangled Eden: ecological change and the Lake Huron Commercial Fisheries, 1835-1978

LaCombe, Kent January 1900 (has links)
Doctor of Philosophy / Department of History / James E. Sherow / This project examines ecological change in Lake Huron during the nineteenth and twentieth century and investigates the causative role of the commercial fisheries in that change. The repeated failures of various regional and international efforts designed to improve management of the lake’s fisheries are also examined. The fundamental argument is that economic considerations were the primary motivations for policy development related to the Great Lakes fisheries. Historically management programs and legislation were shaped by local and regional economic interests. The central focus of this project is Lake Huron. Anthropogenic changes in that lake’s environment dramatically affected the lives and relationships of its non-human inhabitants. The same changes also transformed relationships among human beings who relied on the lake’s resources. Commercial fishermen who operated in the waters of both the United States and Canada relied on the lake for their livelihood, but as the twentieth century commenced the supply of marketable fishes decreased. Competition accelerated and fishermen introduced new technologies and increased their quantity of fishing gear in an effort to maximize their catches in response to fluctuating returns. Economic considerations were of primary concern to both fishermen and government bureaucrats. Lake Huron’s status as an international borderland further complicated the situation. Analysts in both the United States and Canada recognized the dramatically changing conditions of the lakes as reflected through the woes of the commercial fishery. Nonetheless, the germane state, provincial and national governments repeatedly failed in their attempts to develop a cooperative management plan. By the second half of the twentieth century Lake Huron’s embattled biome stood in stark contrast to the once seemingly endless numbers of fishes and flora that sustained the lake’s web of life for hundreds of years.
34

Three Air Quality Studies: Great Lakes Ozone Formation and Nitrogen Dry Deposition; and Tucson Aerosol Chemical Characterization

Foley, Theresa Anne January 2012 (has links)
The Clean Air Act of 1970 was promulgated after thousands of lives were lost in four catastrophic air pollution events. It authorized the establishment of National Ambient Air Quality Standards or (NAAQS) for six pollutants that are harmful to human health and welfare: carbon monoxide, lead, nitrogen dioxide, particulate matter, ozone and sulfur dioxide. The Clean Air Act also led to the establishment of the United Stated Environmental Protection Agency (US EPA) to set and enforce regulations. The first paper in this dissertation studies ozone in the Lake Michigan region (Foley, T., Betterton, E.A., Jacko, R., Hillery, J., 2011. Lake Michigan air quality: The 1994-2003 LADCO Aircraft Project (LAP). Atmospheric Environment 45, 3192-3202.) The Chicago-Milwaukee-Gary metropolitan area has been unable to meet the ozone NAAQS since the Clean Air Act was implemented. The Lake Michigan Air Directors' Consortium (LADCO) hypothesized that land breezes transport ozone precursor compounds over the lake, where a large air/water temperature difference creates a shallow conduction layer, which is an efficient reaction chamber for ozone formation. In the afternoon, lake breezes and prevailing synoptic winds then transport ozone back over the land. To further evaluate this hypothesis, LADCO sponsored the 1994-2003 LADCO Aircraft Project (LAP) to measure the air quality over Lake Michigan and the surrounding areas. This study has found that the LAP data supports this hypothesis of ozone formation, which has strong implications for ozone control strategies in the Lake Michigan region. The second paper is this dissertation (Foley, T., Betterton, E.A., Wolf, A.M.A., 2012. Ambient PM10 and metal concentrations measured in the Sunnyside Unified School District, Tucson, Arizona. Journal of the Arizona-Nevada Academy of Science, 43, 67-76) evaluated the airborne concentrations of PM10 (particulate matter with an aerodynamic diameter of 10 microns or less) and eight metalloids and metals (arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, and nickel) in the southern Tucson metropolitan area. A Tucson company that uses beryllium oxide to manufacture thermally conductive ceramics has prompted strong citizen concern. This study found that the study area has good air quality with respect to PM₁₀ and metals, with ambient concentrations meeting US Environmental Protection Agency and World Health Organization standards. Beryllium was detected only once (during a dust storm) and was ascribed to naturally-occurring beryllium in the suspended soil. The third paper (to be submitted to the Journal of Great Lakes Research) studies nitrogen dry deposition over Lake Michigan and Lake Superior. Numerous studies have shown that wet and dry deposition of nitrogen has contributed to the eutrophication of coastal waters and declining productivity of marine fisheries. Nitrogen dry deposition over the Great Lakes themselves, as opposed to the shorelines, has not been documented in the peer-reviewed literature. This paper calculates nitrogen dry deposition over Lake Michigan and Lake Superior, using aircraft measurements from the LADCO Aircraft Study, and finds that over-water, nitrogen dry deposition is a significant source of nitrogen to Lake Michigan and Lake Superior.
35

Modelling Waves and Currents in Northeastern Lake Ontario to Assess the Impacts of a Proposed Offshore Wind Farm

McCombs, Matthew 02 October 2013 (has links)
A spectral wave model (SWAN) coupled with a depth averaged hydrodynamic model (Delft3D) was used to understand the wave and flow dynamics of the Kingston Basin of Lake Ontario during large winter storm events. This model was then used to assess the impact of an offshore wind farm in the Kingston Basin. Results over different model domains with various forcing methods were compared to achieve the highest correlation with wave, current and water level observations from several locations. Storm events were modelled over the complex bathymetry of the basin and results were verified using wave and current profiler data collected during the winters of 2009-10 and 2011-12. Waves were composed of both locally generated wind sea and swell from the main basin of Lake Ontario, while flows throughout the Kingston Basin showed a complex circulation pattern. This circulation is composed of several wind-driven gyres, which are magnified during storm events. The impact of waves on the circulation patterns within the basin is highest in shallow areas where wave breaking drives circulation. To simulate a wind farm, a transmission coefficient was used in the wave model to represent the effects on waves, and an energy loss term was added to the hydrodynamic momentum equations to represent the added drag of the piles on the circulation. The results indicate that the coastal areas in eastern Lake Ontario will be minimally affected. The headlands of Big Sandy Bay, Wolfe Island, could see the largest coastal effects with changes in significant wave height predicted to be < 2%. The majority of impacts to circulation occur in the near-field, with changes in current magnitude of < 0.08 m s-1 (up to 50%). Areas near Wolfe Island exhibit changes of ~ 0.05 m s-1 (30 %), although overall circulation patterns throughout the basin are not affected. The majority of changes to surface waves and wind-driven currents are due to wind farm position with respect to wind direction and the re-direction of flows and waves as they pass through the wind farm. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-09-30 09:30:01.042
36

The Importance of Thermal Habitat Quality for Pumpkinseed (Centrarchidae: Lepomis gibbosus) in Small and Constructed Coastal Embayments Along the Northwest Shoreline of Lake Ontario

Murphy, Shidan 11 January 2012 (has links)
Along the Toronto shoreline, small coastal embayments (0.4 – 32 ha) are being constructed or modified to restore warmwater fish habitat. I describe how Lake Ontario (hereafter the Lake) alters the thermal regime of these small coastal embayments, how the altered thermal regimes affect growth and survival of age-0 warmwater fishes, and how the thermal habitat quality for such fishes can be improved by altering embayment design. During the warming period of the ice-free season, embayments warm faster than the Lake and so are cooled by exchanges with the Lake. Later in the year Lake exchange warms the rapidly cooling embayments, but the net effect of Lake-embayment exchange is cooling. The degree of cooling in Toronto’s small coastal embayments varies; many have temperatures near that of the Lake, and a few warm as much as local ponds. Age-0 pumpkinseed (Lepomis gibbosus) can fail to reach sufficient size to survive the winter in cooler embayments because their spawning is delayed and their growth is slowed. Most embayments along the Toronto shoreline are too cold to produce age-0 fish that can survive the winter, but all embayments are occupied by age >1 pumpkinseed, suggesting movement from warmer to cooler embayments. Using otolith microchemistry to identify natal embayments of fish, I confirm that age-0 and age-1 pumpkinseed, as well as age-0 largemouth bass (Micropterus salmoides) and age-0 yellow perch (Perca flavescens), exist in metapopulations. Embayment bathymetry is a poor predictor of temperature because almost all embayment flushing rates are very fast, usually 1-2 days. Warmer embayments are located in protected areas of Lake Ontario and receive waters that have already heated substantially. Cold embayments are located along the exposed shoreline of Lake Ontario. To protect embayments from cold lake waters, the cross-sectional area of embayment channels need to be reduced to 1-10% of their current size.
37

Beyond Indicators and Reporting: Needs, Limitations and Applicability of Environmental Indicators and State of the Environment Reporting

Da Silva, Sarah Elizabeth 13 January 2010 (has links)
This research examines the perceptions and use of environmental indicators and state of the environment reports by local government and Conservation Authority decision makers and practitioner’s within the Ontario portion of the Great Lakes and St. Lawrence basin. Participants describe their information needs and how indicators and SOER are used at the local level; and what limitations or challenges they face to bridge the gap between monitoring information and policy. A multi-method approach including a web-based survey and follow-up telephone interviews was the primary data collection method used. Indicator and SOER knowledge and information are further explored to determine information exchange amongst different levels of governance. To review the dissemination of indicator and SOER information from a higher spatial scale down to the local level, the State of the Great Lakes environmental indicators and SOER, developed by the governments of Canada and the United States served as a case study.
38

Beyond Indicators and Reporting: Needs, Limitations and Applicability of Environmental Indicators and State of the Environment Reporting

Da Silva, Sarah Elizabeth 13 January 2010 (has links)
This research examines the perceptions and use of environmental indicators and state of the environment reports by local government and Conservation Authority decision makers and practitioner’s within the Ontario portion of the Great Lakes and St. Lawrence basin. Participants describe their information needs and how indicators and SOER are used at the local level; and what limitations or challenges they face to bridge the gap between monitoring information and policy. A multi-method approach including a web-based survey and follow-up telephone interviews was the primary data collection method used. Indicator and SOER knowledge and information are further explored to determine information exchange amongst different levels of governance. To review the dissemination of indicator and SOER information from a higher spatial scale down to the local level, the State of the Great Lakes environmental indicators and SOER, developed by the governments of Canada and the United States served as a case study.
39

The Importance of Thermal Habitat Quality for Pumpkinseed (Centrarchidae: Lepomis gibbosus) in Small and Constructed Coastal Embayments Along the Northwest Shoreline of Lake Ontario

Murphy, Shidan 11 January 2012 (has links)
Along the Toronto shoreline, small coastal embayments (0.4 – 32 ha) are being constructed or modified to restore warmwater fish habitat. I describe how Lake Ontario (hereafter the Lake) alters the thermal regime of these small coastal embayments, how the altered thermal regimes affect growth and survival of age-0 warmwater fishes, and how the thermal habitat quality for such fishes can be improved by altering embayment design. During the warming period of the ice-free season, embayments warm faster than the Lake and so are cooled by exchanges with the Lake. Later in the year Lake exchange warms the rapidly cooling embayments, but the net effect of Lake-embayment exchange is cooling. The degree of cooling in Toronto’s small coastal embayments varies; many have temperatures near that of the Lake, and a few warm as much as local ponds. Age-0 pumpkinseed (Lepomis gibbosus) can fail to reach sufficient size to survive the winter in cooler embayments because their spawning is delayed and their growth is slowed. Most embayments along the Toronto shoreline are too cold to produce age-0 fish that can survive the winter, but all embayments are occupied by age >1 pumpkinseed, suggesting movement from warmer to cooler embayments. Using otolith microchemistry to identify natal embayments of fish, I confirm that age-0 and age-1 pumpkinseed, as well as age-0 largemouth bass (Micropterus salmoides) and age-0 yellow perch (Perca flavescens), exist in metapopulations. Embayment bathymetry is a poor predictor of temperature because almost all embayment flushing rates are very fast, usually 1-2 days. Warmer embayments are located in protected areas of Lake Ontario and receive waters that have already heated substantially. Cold embayments are located along the exposed shoreline of Lake Ontario. To protect embayments from cold lake waters, the cross-sectional area of embayment channels need to be reduced to 1-10% of their current size.
40

Traditional Methods and New Fluorometric Methods to Determine Phytoplankton Nutrient Status for Freshwater Ecosystems, and Their Application in the Lower Laurentian Great Lakes

Rattan, Kimmy January 2009 (has links)
The Laurentian Great Lakes are the largest system of freshwater on earth containing 22% of the world’s supply. Although part of a single system, each lake shows substantial variation regarding physical, chemical and biological parameters. The main goals of this thesis were to characterize the nutrient status of natural phytoplankton communities while comparing several commonly used measurements of nutrient status and Chlorophyll a (Chl a) fluorescence measurements. The study sites include the western basin (WB), west-central basin (WCB), and central basin (CB) of Lake Erie, the Bay of Quinte in Lake Ontario, and Colpoys Bay in Lake Huron. Independent measures of nutrient status were assessed by measurements of nitrogen (N) debt, phosphorus (P) debt, particulate C:N:P ratios, and alkaline phosphatase activity (APA). Variable fluorescence of chlorophyll a was measured by pulse amplitude modulated (PAM) fluorometry and fast repetition rate (FRR) fluorometry in parallel with the independent measures. In 2005, the phytoplankton communities in Lake Erie were generally N deficient in May, P deficient in June, and neither N nor P deficient in September. The maximum dark adapted quantum yield (Fv/Fm) measured by PAM or FRRF was lower in May and June, and maximal in September, while the functional absorption cross section of photosystem II (σPSII) was maximal in May and June, and minimal in September. Relationships between the variable fluorescence indicators and independent measures of nutrient status showed strong associations with N or P deficient sites having low Fv/Fm and high σPSII. In 2006, the electron transport rate (ETR) and the initial slope (α) derived from the PAM fluorescence rapid light-response curves (RLC) were compared to independent measures and Fv/Fm measurements in Lake Erie. Relationships between ETR, α, independent measures of nutrient status, and Fv/Fm measurements revealed strong associations with nutrient status. Confirming previous reports, N deficiency was highest in the WB during isothermal conditions while P deficiency was highest in the CB during summer stratification. The fluorescence parameters generally decreased as the severity of N and P deficiency increased. N and P enrichment assays also revealed increased values of Fv/Fm, ETR, and α from N and P deficient samples over twenty-four hours. Additionally, spatial variability of P status was evaluated during summer stratification. Colpoys Bay, the most oligotrophic site, had the strongest P deficiency, and evidence for existence of P deficiency was weakest in the Bay of Quinte, the most eutrophic site. Nutrient enrichment assays revealed that all fluorescence parameters showed a positive response to P additions in oligotrophic sites, with no response in eutrophic sites. Community structure was also associated with nutrient status and Chl a fluorescence at all locations. In P deficient sites, nano-flagellates such as chrysophytes and cryptophytes were prevalent; cyanobacteria were dominant at sites that displayed N deficiency.

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