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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.
471

The Timing of Reproduction is Responding Plastically, not Genetically, to Climate Change in Yellow-Bellied Marmots (Marmota flaviventer)

St Lawrence, Sophia Helen 23 August 2022 (has links)
With global climates changing rapidly, animals must adapt to new environmental conditions with altered weather and phenology. Key to adapting to these new conditions is adjusting the timing of reproduction to have offspring when the conditions are best to maximize growth and survival. Using a long-term dataset on a wild population of yellow-bellied marmots (Marmota flaviventer) at the Rocky Mountain Biological Laboratory (RMBL), we investigated how the timing of reproduction changed with changing spring conditions over the past 50 years. Marmots are hibernators with a four-month active season. It is thus crucial to reproduce early enough in the season to have time to prepare for hibernation, but not too early so as snow cover prevents access to food. Importantly, climate change in this area has increased spring temperatures by 5 °C and decreased spring snowpack by 50 cm over the past 50 years. This directional change in climate may have caused adaptation. Given that adaptation to environmental conditions could arise from either microevolution or phenotypic plasticity, we evaluated how female marmots adjust the timing of their reproduction and estimated the importance of both genetic variance and plasticity in the variation in this timing. We show that, within a year, the timing of reproduction is not as tightly linked to the date a female emerges from hibernation as previously thought. We report a positive effect of spring snowpack but not of spring temperature on the timing of reproduction. There is inter-individual variation in the timing of reproduction but not in its response to changing spring conditions. Genetic variance in the timing of reproduction is low, and heritability was 8%. Earlier pup emergence date increases the number and weighted proportion of pups surviving their first winter, indicative of directional selection on this trait. The same pattern is not found for litter size with no effect of pup emergence date on the number of pups born. Further, all three of these traits are not under stabilizing selection. Taken together, it seems that we should expect some changes in this population with changing climatic conditions, but because of plasticity and not due to natural selection. Further, future studies on the marmots should not operate under the assumption that females reproduce immediately following their emergence.
472

Three Essays on Policy Evaluations in Oligopoly Markets

Guo, Ziyu January 2021 (has links)
No description available.
473

A Utopian Failure: The One-Tonne Challenge, Climate Change and Consumer Conduct

Lait, Michael C. January 2009 (has links)
The object of this study is a program of government that has, as its immediate objective, the modification and regulation of consumer conduct deemed pertinent to climate change. Drawing from the analytical grid and conceptual tools of governmentality, this study has organized and analyzed an archive of documents related to the One-Tonne Challenge, a ‘public education’ program implemented by the Government of Canada from 2003 to 2006. There are numerous forms of conduct targeted by this program, involving many of the mundane and routine practices of everyday life. Despite their heterogeneity, the targeted forms of conduct can all be measured and evaluated according to the greenhouse gas (GHG) inventory, an ecological technology of government that has had its application extended to the ‘personal’ level. As consumers increasingly engage in practices that are energy efficient, a ‘low intensity GHG emission lifestyle’ will emerge as a new societal norm, which is declared to be the ‘ultimate strategic objective’ of the program. The analysis indentifies and describes two rationalities of government articulated within the archive of the program. Liberal principles and assumptions regarding the market economy are ascendant in practice; they delimit the range of governmental techniques that can be put into operation by the state. Nevertheless, the objectives and technologies of this program belong to an ecological rationality of government. It problematizes the liberal emphasis on ‘voluntary action’ and advances state planning of the market economy through price formation as a necessary governmental technique with which to manipulate the demand for energy and ensure that consumers become energy-efficient. The conclusion interprets and diagnoses the main dangers that could arise from the radical transformation of the market economy that would be brought about by an ecological political reason.
474

Emotions, Moral Formation, and Christian Politics: Rereading Karl Barth

Cahill, Jonathan Michael January 2021 (has links)
Thesis advisor: Lisa S. Cahill / This subject of this dissertation is moral formation, that is, the process by which people become more just in their interactions with others. Moral growth, then, refers to how the moral capacities of individuals are developed to facilitate right decisions and good actions. Additionally, moral formation here refers to the shaping of society in ways that bring about more just social arrangements. A key claim is that emotion is vital for both the moral shaping of individuals and society. Emotions fitting to the struggle for justice are developed through relationships and participation in communities of growth.This project is undertaken in dialogue with Karl Barth. I begin in chapter 1 by considering Barth’s theological anthropology grounded in God’s self-disclosure in Jesus Christ which contends that true humanity consists in living in covenant partnership with God and solidarity with fellow humanity. To more closely correspond to this determination is the goal of moral formation. Building on his relational conception of the self, I argue that Barth provides an account of moral formation in his treatment of the growth of the community. Moral progress is rooted in participation in the body of Christ that is growing as a hearing community and increasing in the practice of holy things such as worship and service. Chapter 2 and 3 argue that moral growth does not occur through rational capacities alone, but depends on the development of emotions. These interdisciplinary chapters turn to recent studies of emotions in the natural and social sciences and philosophy. After a survey of various debates, I argue for a relational and cognitive conception of emotions and highlight their critical role in regulating group and social relations. Emotions are fundamental to interpersonal interactions, to group relations, and for the reinforcement and disruption of social structures. While these disciplines provide insight into the nature and development of emotions, I return in chapter 4 to Barth for the project of constructing a normative account. While we must not attempt to supplant the command of God which decides the good, I contend that we ought to evaluate emotions by whether they engender communion with God, solidarity with fellow humans, and care for creation. This account of emotion is further developed in chapter 5 by turning to Barth’s apocalyptic account of the kingdom of God and the lordless powers. While we wait on God to bring about the consummation of the kingdom, Christians are yet to actively struggle for justice in anticipation of that day. This entails unmasking and resisting the powers. Barth’s account of unmasking the lordless powers draws attention to the ways they shape human emotions. He also underscores the importance of emotions, such as hope, in the human struggle for justice. Drawing on Barth’s earlier account of growth, I highlight the role of the church in forming these emotions. This account of moral formation and emotion is illustrated through the example of climate change. A community shaped by love for God, solidarity with other creatures, and a concern for all of creation leads to an awareness of hegemonic forces and fosters emotions shaped by the kingdom that enables the struggle for climate justice. / Thesis (PhD) — Boston College, 2021. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Theology.
475

Deforestation and the Transformation of the Landscape of North China: prehistory - present

Moore, Alan H. 01 November 2010 (has links)
Environmental evidence shows that 10,000 years ago North China was primarily a lush deciduous forest. Like many other regions of the planet, this landscape has been dramatically transformed by human activity, yet unusually this mostly occurred long ago under pre-industrial conditions. Fortunately China has a long recorded history of human activity. Complementary environmental evidence helps to extend this record into prehistory, for even prehistoric Chinese substantially altered their environment. The first half of this study examines historical and physical evidence in order to better explain how North China's forests disappeared. Only recently have there been regional scale activities focused on reversing this tragic trend. Despite many claims of successes in afforestation, there are serious shortcomings in the collection of government statistics and known limitations to area-based forest assessments, so it is difficult to say with much confidence what is happening with North China's forests today. Phenological measurements from space-based instruments have been effectively used to characterize vegetation trends. In the second half of this study, MODIS sensor observations for 2000-2009 are collected for five study sites and are used to characterize vegetation change over the past decade, independent of government statistics and area-based estimates. Forests provide tangible benefits to environmental and human well-being. Forest health and growth are critical to addressing global climate change. Much attention has been focused on China's efforts to combat deforestation. A better understanding of North China's forest trends — both past and present — may offer valuable lessons for our environmental future. / Master of Science
476

Lacustrine records of Holocene climate and environmental change from the Lofoten Islands, Norway

Balascio, Nicholas L 01 January 2011 (has links)
Lakes sediments from the Lofoten Islands, Norway, can be used to generate well resolved records of past climate and environmental change. This dissertation presents three lacustrine paleoenvironmental reconstructions that show evidence for Holocene climate changes associated with North Atlantic climate dynamics and relative sea-level variations driven by glacio-isostatic adjustment. This study also uses distal tephra deposits (cryptotephra) from Icelandic volcanic eruptions to improve the chronologies of these reconstructions and explores new approaches to crypto-tephrochronology. Past and present conditions at Vikjordvatnet, Fiskebølvatnet, and Heimerdalsvatnet were studied during four field seasons conducted from 2007–2010. Initially, each lake was characterized by measuring water column chemistry, logging annual temperature fluctuations, and conducting bathymetric and seismic surveys. Sediment cores were then collected and analyzed using multiple techniques, including: sediment density, magnetic susceptibility, loss-on-ignition, total carbon and nitrogen, δ13C and δ 15N of organic matter, and elemental compositions acquired by scanning X-ray fluorescence. Chronologies were established using radiocarbon dating and tephrochronology. A 13.8 cal ka BP record from Vikjordvatnet provides evidence for glacial activity during the Younger Dryas cold interval and exhibits trends in Ti, Fe, and organic content during the Holocene that correlate with regional millennial-scale climate trends and provide evidence for more rapid events. A 9.7 cal ka BP record from Fiskebølvatnet shows a strong signal of sediment inwashing likely driven by local geomorphic conditions, although there is evidence that increased inwashing at the onset of the Neoglacial could have been associated with increased precipitation. Heimerdalsvatnet provides a record of relative sea-level change. A 7.8 cal ka BP sedimentary record reflects changes in salinity and water column conditions as the lake was isolated and defines sea-level regression following the Tapes transgression. Cryptotephra horizons were identified in sediments of Heimerdalsvatnet, Vikjordvatnet, and Sverigedalsvatn. They were also found in a Viking-age boathouse excavated along the shore of Inner Borgpollen. These include the GA4-85, BIP-24a, SILK-N2, Askja, 860 Layer B, Hekla 1158, Hekla 1104, Vedde Ash, and Saksunarvatn tephra. This research project also explored the use of scanning XRF to locate cryptotephra in lacustrine sediments and presents experimental results of XRF scans of tephra-spiked synthetic sediment cores.
477

Identifying streamflow changes in western North America from 1979 to 2021 using Deep Learning approaches

Tang, Weigang 11 1900 (has links)
Streamflow in Western North America (WNA) has been experiencing pronounced changes in terms of volume and timing over the past century, primarily driven by natural climate variability and human-induced climate changes. This thesis advances on previous work by revealing the most recent streamflow changes in WNA using a comprehensive suite of classical hydrometric methods along with novel Deep Learning (DL) based approaches for change detection and classifica- tion. More than 500 natural streams were included in the analysis across western Canada and the United States. Trend analyses based on the Mann-Kendall test were conducted on a wide selection of classic hydrometric indicators to represent varying aspects of streamflow over 43 years from 1979 to 2021. A general geograph- ical divide at approximately 46◦N degrees latitude indicates that total streamflow is increasing to the north while declining to the south. Declining late summer flows (July–September) were also widespread across the WNA domain, coinciding with an overall reduction in precipitation. Some changing patterns are regional specific, including: 1) increased winter low flows at high latitudes; 2) earlier spring freshet in Rocky Mountains; 3) increased autumns flows in coastal Pacific North- west; and 4) dramatic drying in southwestern United States. In addition to classic hydrometrics, trend analysis was performed on Latent Features (LFs), which were extracted by Variation AutoEncoder (VAE) from raw streamflow data and are considered “machine-learned hydrometrics”. Some LFs with direct hydrological implications were closely associated with the classical hydrometric indicators such as flow quantity, seasonal distribution, timing and magnitude of freshet, and snow- to-rain transition. The changing patterns of streamflows revealed by LFs show direct agreement with the hydrometric trends. By reconstructing hydrographs from select LFs, VAE also provides a mechanism to project changes in streamflow patterns in the future. Furthermore, a parametric t-SNE method based on DL technology was developed to visualize similarity among a large number of hydro- graphs on a 2-D map. This novel method allowed fast grouping of hydrologically similar rivers based on their flow regime type and provides new opportunities for streamflow classification and regionalization. / Thesis / Doctor of Philosophy (PhD)
478

HOUSING AND ENVIRONMENTAL JUSTICE: DEVELOPING A PATH FORWARD TO A RACIALLY JUST AND CLIMATE-READY PHILADELPHIA

Montes, Naida Elena 08 1900 (has links)
The research conducted for this dissertation was methodologically designed to explore human environments and the role of housing as a space that makes an integral difference in the livelihoods and well-being of residents facing environmental burden and climate risks. The research explores the following questions: 1) How does the contextual scale of the home serve as a support or detriment to well-being and climate-preparedness for residents living in neighborhoods that have undergone degradation in the urban environment resulting from Philadelphia’s history of racialized planning practice? 2) How can the housing structure be reconceptualized as the scale which holds the fullest potential of resilience mitigation and climate preparedness in the built environment? 3) How does analytically centering the focus on the “home” and housing environments within the geographical urban landscape fill a gap in understanding about what ties people to place physically and socio-economically connects people to communities? Focusing in on the “Home” as a scale of geographic and qualitative inquiry, deriving its significance from resident voice expands the body of literature that can bridge the theoretical and advocacy based analytical framings of Black feminist thought and environmental justice to highlight the importance of housing in the urban landscape to find solutions to equitable housing concerns in the city. The objective of the research is to understand how environmental neighborhood conditions resulting from racialized planning practice manifest in present day socio-environmental outcomes and influence resident well-being even within the context of the “home”. I argue that climate change vulnerability and environmental burden can be more holistically understood and mitigated by reframing the scale at which environmental justice claims and research is formulated and analyzing the home itself as an environmental site of struggle and/or resilience. / Geography
479

Multi-jurisdictional analysis of integration of climate change considerations in regulations and guidelines across 16 environmental impact assessment (EIA) regimes

Mayembe, Rose 23 March 2023 (has links) (PDF)
The contribution of the human activities to climate change is well understood. Yet integration of climate change considerations in tools designed to govern activities affecting the environment, such as Environmental Impact Assessment (EIA), remains underdeveloped and inconsistently applied. There is no clear direction on what measure of consideration is sufficient for environmental decision-making on potential impacts on the climate for proposed policies, programs, plans and projects. This research reviews progress across a range of 16 EIA regimes and outlines the potential for integration of climate change considerations in EIA. The research used a desk review of EIA literature to identify and assess regulations and guidelines that have been established to promote the integration of climate change in EIA. A typology of levels of integration was developed to guide analysis across multiple EIA regimes. The findings identify a global and growing normative expectation for climate change considerations to be integrated into EIA and describe the range of ways this is done across the regimes selected. Climate change integration in EIA is typically concerned with climate change mitigation, specifically greenhouse gas emissions from proposed developments. Fewer regimes are concerned with climate change adaptation, and in general, an integration deficit is identified for regimes where climate change is partially considered. Several challenges to integrating climate change in EIA are identified, including lack of practice guidelines and regulatory frameworks. Reflecting on the variety of approaches, the discussion extends typologies of integration in EIA to examine and provide a better understanding of substantive consideration of climate change in EIA. Examples of high integration indicate that EIA holds potential to play a substantive role in environmental governance at project level decision making affecting climate change. However, the range of examples also cautions that many domestic obstacles can militate against integration including political, socio-technical, and economic imperatives – particularly those affecting sectoral and scope exclusions. Nevertheless, developments across some regimes indicate leverage points for greater integration, including the role of EIA review to establish new precedents for the relevance of climate change to EIA. Potential future research and practice directions are identified, including development of regulations and practice guidelines, inclusion of climate change adaptation aspects, strengthening postdecision monitoring, application to all relevant sectors and activities, alignment with SEA, and integration across all stages of the EIA process.
480

Becoming vulnerable in the era of climate change: Questions and dilemmas for a pedagogy of vulnerability

Kelly, Ute, Kelly, Rhys H.S. 18 December 2019 (has links)
Yes / This chapter aims to be both an exploration and an example of (or an experiment with) a ‘pedagogy of vulnerability’. It reports and reflects on efforts to create spaces for co-inquiry with students, as attempts to both escape the limits of traditional pedagogic relationships and to create spaces and opportunities for deeper learning. We consider how or whether the central premise of a ‘pedagogy of vulnerability’ – that purposeful and selective acts self-disclosure by teachers can help build the conditions of trust and care needed for dialogue around emotionally and politically challenging topics – is borne out in our experience.

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