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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.
1

The impact of historic logging on woody debris distribution and stream morphology in the Great Smoky Mountains National Park, North Carolina-Tennessee

Morris, Christopher M. 01 May 2008 (has links)
In the early 1900s, large sections of the Great Smoky Mountains were intensively logged. Since then, most locations have been allowed to naturally become forest-covered again, resulting in areas of secondary growth and old growth forest. To determine whether differences in large woody debris (LWD) loading and channel morphology persist today, I measured LWD, channel widths and depths, and channel bed sediments of streams in old and secondary growth forest in the Great Smoky Mountains National Park. LWD pieces in streams in old growth had larger mean diameters and lengths compared to LWD in streams in secondary growth forest. Streams in old growth had 5.6 times more LWD volume than those in secondary growth. More LWD pieces were in debris dams in old growth than in secondary growth forest. Channel bed sediment size did not differ significantly between streams in old and secondary growth forest. Channel widths and depths were signifiantly larger in streams in old growth forest. LWD pieces affected channel depth primarily by creating pools and causing deposition of sediment. LWD affected width by directing stream flow toward banks and by protecting banks from erosion. I observed that the orientation of LWD was important in determining its geomorphic role. Although I found no relationship between LWD loading and watershed area, I found a relationship between watershed area and the importance of LWD in impacting channel morphology. Despite differences in LWD frequency and total volume, streams in old and secondary growth forest differed little in width and depth in the largest watersheds in this study. However, in smaller watersheds, streams in old growth were not as narrow or as shallow as streams in secondary growth. LWD loading can vary substantially between streams, even those with sim- ilar surrounding forest types, climate, and disturbance histories; therefore, caution should be exercised when using LWD loading rates from other studies in environmental management. Despite nearly 80 years of forest regrowth, LWD loading and channel mor- phologies of streams still show the impacts of logging.
2

Ecological Restoration's Genetic Culture: Participation and Technology in the Making of Landscapes

Rossi, Jairus 01 January 2013 (has links)
Practitioners of ecological restoration are increasingly adopting a genetic perspective when recreating historical landscapes. Genes are often endowed with the capacity to reveal specific and distinct relationships between organisms and environments. In this dissertation, I examine how genetic technologies and concepts are shaping ecological restoration practices. This research is based on two and a half years of fieldwork in Chicago. I employed participant observation and semi-structured interviews to compare how restorationists in two plant science institutions employ genetic concepts in their projects. One institution uses high-tech genetic methods to guide practice while the other uses lower-tech genetic approaches. Each group has distinct, yet internally diverse ways of deciding which seeds are ‘local enough’ to be included in a project. This research theorizes how classification differences regarding native seeds are part of a broader set of genetic logics I refer to as ‘genetic epistemologies’. Specifically, I ask how genetic technologies circumscribe different ways of seeing and making landscapes. I compare how restorationists delineated valid seed sourcing regions for restoration projects based on their genetic definitions of ‘native’ species. Drawing from science & technology studies, political ecology, and cultural landscape geography, I illustrate how restorationists incorporate cultural preferences, funding imperatives, aesthetics, and discourses about nature into their particular genetic epistemology. From this research, I offer the following conclusions. By incorporating genetic technology into ecological restoration, many practitioners feel their work will achieve more precision. Yet this perspective is typical of those who do not directly use genetic technologies. Scientists using direct genetic analyses are much more reserved about the potential of their technologies to match organisms to environments. Second, individuals or groups often come into conflict when attempting to apply different genetic epistemologies to the same problem. These conflicts are resolved in the course of planning and implementing a restoration project. Finally, direct genetic methods are only useful in restoration work involving rare or endangered species. Despite the limited utility of genetic technology in restoration, this approach is becoming influential. Chicago’s high-tech plant science institution is discursively reshaping the goals and approaches of native plant institutions that do not use these technologies.
3

From Farm to Fork to Landfill: Food Waste and Consumption in America

Nunley, Mariel 01 April 2013 (has links)
This thesis focuses on the creation and disposal of food waste in the United States. Food waste is a specific yet highly critical issue that implicates the large, incongruous systems of both food production and waste disposal. Waste is created throughout the food supply chain, with producers as well as consumers guilty of throwing away good food. Rather than repurpose food as compost or donate it to those in need, wasted food, although completely biodegradable and often edible, is mixed in with the rest of our garbage and disposed of in a landfill. By evaluating the systems of waste disposal and food production, I illustrate the ways in which both of these industries encourage the creation of food waste and conceal its harmful effects. I argue that it is necessary to prioritize source reduction of wasted food, rather than rely upon infrastructure that keeps waste “out of sight, out of mind.” Despite the factors that shelter it from our critical consideration, it has become necessary to prioritize food waste as a legitimate environmental, social, and economic concern.
4

COUNTING ON THE ENVIRONMENT: MEASURING AND MARKETING ECOSYSTEM SERVICES IN OREGON

Nost, Eric 01 January 2013 (has links)
New markets for the conservation of so-called ecosystem services, like the ability of a wetland to mitigate floods, are emerging worldwide. According to environmental economists, these markets require some metric - ecological or otherwise - that names the relevant characteristics of the service to be traded as a commodity. But while this is often assumed to be a simple task of science, I argue that the environmental regulators, eco-entrepreneurs, and conservationists who actually design and implement metrics are not so easily brought into agreement. In “rolling-out” revamped metrics and protocols, regulators and their conservationist allies in one market in Oregon haven’t established the conditions for market success so much as they have constrained entrepreneurs. The solutions to ecosystem destruction 20 years ago - privatization, commodification, and commercialization - have become the obstacles which limit the market’s future viability. The moments when capitalists find themselves saying “let’s sell nature to save it” - or when states say it for them - can spell trouble for capitalists at the same time that they seem like their escape hatch. Still, the short-term and long-term effects of market design may differ; barriers to the market now may prove to be its success later.
5

Improving volcano risk communication at the Long Valley Caldera and Mono-Inyo Craters volcanic system, eastern California, USA

Peers, Justin, Reeves, Ashleigh, Gregg, Christopher, Lindell, Michael K, Joyner, Andrew 05 April 2018 (has links)
Exposure to volcano hazards can lead to crises; with or without an eruptive event. Therefore, it is important to distinguish that volcanic events (unrest & eruptions) are physical phenomena while volcanic crises are social. Volcanic eruptions, unlike some other geologic hazards are often preceded by weeks or months of precursors, which offer the opportunity to reduce risk by early intervention. However, resistance to discussion of local hazards can hinder stakeholders’ (emergency managers, scientists, etc.) ability to mitigate volcano hazards and create well-informed protocols to respond when disaster strikes. The Long Valley Caldera (LVC) east of California’s Sierra Nevada Mountain Range, has experienced unrest since 1978, at which time a M5.6 earthquake ended 20 years of seismic quiet. Seismicity continued, followed by significant ground deformation and doming of the caldera floor, increased fumarolic activity, and CO2 degassing which has contributed to tree kills and human fatalities. Extensive research in volcano science provides an understanding of the physical phenomena behind the mechanics of volcanos, but limited resources have been dedicated to understanding human processes in response to volcano hazards and their corresponding disasters. Misconceptions and uncertainty surrounding organizational and physical communication of risk information can amplify economic consequences resulting from volcanic crises. This study will utilize two methods to obtain perceptions that local stakeholders and residents hold towards hazards in their region; and their confidence in the agencies that are responsible in responding to crises. A questionnaire sent to 1,200 households in February, 2018 asked head-of-households about their awareness of volcano hazards, preparedness for a volcano emergency, and perceptions of stakeholders responsible for decision making and warning systems. Mental model interviews conducted with stakeholders in summer, 2018 will provide insight on methods used by decision makers tasked with responding to disasters at LVC and the greater Long Valley Volcanic Region (LVVR). Mental models, i.e. schema, are a representation of how a person thinks about and mentally conceptualizes objects, events, and relationships in the real world. Robust to change, mental models are not easily altered; however, new information is either dismissed or made to fit within previous beliefs. Research suggests that the more discordant new information is with respect to existing beliefs, the more likely the information is to challenge those beliefs, providing opportunities for change. Together, these household and stakeholder studies will identify issues surrounding risk communication and risk management to improve tools that communicate the uncertainty of volcanic activity in the LVVR.
6

Regional Temperature Trends & Variations in the Contiguous United States from 1935 to 1986

Alkolibi, Fahad 01 July 1991 (has links)
The temperature trends and variations of the contiguous United States as a whole and ten designated regions were investigated from 1935 to 1986. To obtain reliable results, 263 stations of the Historical Climate Network (HCN) were used. The HCN stations are corrected for many non-climatic factors which may bias the data. The data for the contiguous United States reveals that the annual, summer, and winter temperatures are free of clear positive or negative trends. Unlike the annual and summer data, winter temperatures exhibit relatively strong variations. Each region was then studyed individually. The summer temperatures for all the ten regions were free of significant trends except Region 2 (Central East Region), which exhibited a significant negative trend. The winter temperatures of the ten regions also lack a statistical significance except for Region 3 (Southeast Region) which shows a significant negative trend. The annual temperatures for the ten regions were also significant except for Regions 2 and 5 (Central East Region and Southern Plains Region). These two regions exhibited significant negative trends. The annual temperature trends for nine of the ten regions were negative while the annual temperatures for the United States as a whole show a positive trend. None of these trends were significant except for Regions 2 and 5. To examine whether or not the differences between the trends of the contiguous United States as a whole and those of the ten regions represents a significant departure from each other, the Expansion Method was used. Applying this method on the annual, summer and winter trends indicated that these differences did not represent a significant departure from those of the contiguous United States. By studying the annual spatial temperature variations of the ten regions it was found that in more than 80% of the years, when the region with the highest positive deviation is in the western United States, the region with the highest negative deviation is in the eastern United States and visa versa.
7

Mapping the Desertification Process in Southern Morocco Using Remote Sensing Data

Benkhalti, Abdellah 01 July 1987 (has links)
Desertification is a problem occurring in arid and semiarid zones all over the world. It is a consequence of mismanagement of the land. Human activities and livestock pressure on such fragile ecosystems lead to a deterioration of the soil by increasing its salinity, lessening its moisture, and covering it with sand and dust. Aerial photographs and satellite images constitute a tool for mapping and monitoring the desertification process. Multispectral data can assist in detecting the indicators of desertification in early stages in order to plan adequate action. The improvement of the resolution of satellite images and the fact that they are available on a periodic basis make the use of these data suitable for mapping the evolution of desert patches at large scales. The green band of Landsat MSS is used in this study. Two images taken, respectively, in 1976 and 1985 and covering the province of Ouarzazate in southern Morocco are used to map the desertification process and its evolution in the region. At the scale used and given the ground resolution of the MSS (80 meters), significant changes were found between the two images. However, changes occurring at scale smaller than 80 meter square were impossible to detect by visual interpretation of this band.
8

Where Did They Go? Analysis of Out-Migration from Mammoth Cave National Park, 1920-1940

Eke, Collins U. 01 April 2019 (has links)
The 52,830-acre Mammoth Cave National Park, located in the karst region of south-central Kentucky, was formally established in July of 1941, culminating nearly three decades of park creation that displaced several thousand residents of the region. This thesis sampled residents using the 1920 manuscript census for the United States Census of Population and Housing and tracked their migration destinations using the 1930 and 1940 manuscript censuses. Migration patterns for the entire sample, as well as by race and homeownership status, were identified through mapping. Out-migrants generally chose locations north, west, and east of the proposed park area, noticeably neglecting the Deep South. Statistical analyses proved significant differences between proportions of Black out-migrants and White out-migrants moving to urban areas, as well as those of homeowners and renters who were not successfully tracked during analysis. The research underlines unintended consequences of the forced out-migration from the proposed Mammoth Cave National Park and several factors that contributed to it. In the process, the thesis fills a gap in research on Mammoth Cave National Park and sheds light on an important aspect of Kentucky’s history.
9

PRODUCING TRADITION: INTERNATIONAL STANDARDS AND DEVELOPMENT IN JORDANIAN OLIVE OIL

Cook, Brittany Eleanor 01 January 2018 (has links)
This dissertation project examines how value is changed and created through organic certification and the universalizing ideas of capacity building within the olive oil industry in Jordan and how these shifts affect the social and material processes of production. I approach organic olive oil production in Jordan as one method that producers use in accessing markets and capacity building. By shifting from looking strictly at organic certified farms to examining the larger context of capacity building and international standards, I identify how organic is just one strategy in a larger effort to diversify Jordanian agricultural production and to access global markets. However, more work needs to be done to elucidate how development shapes organic and other ‘alternative’ initiatives differently than in European and North American contexts. In order to do this, I incorporate postcolonial critiques of GPN and critical development studies to further our understanding how of these certifications and standards are taken up, challenged, and sometimes abandoned in favor of other production methods in local spaces of the Global South. The local embeddedness of olive oil production and the relative recent history of export provide a unique opportunity for examining how producers, organizations, governments, and universities create new export industries. In order to trace how these capacities are built, this dissertation examines the following questions: how is value redefined as producers try to access distant consumers? What are the material and social strategies? In answering these questions, I examine three types of value: taste/sensory, organic/environmental, and gendered tradition. Through the examination of these values, I found that they were each built through a mechanism: re-asetheticizing local taste, creating a new commodity network, and pushing domestic labor into the public sphere. Each mechanism has intended and unintended consequences for the social relations of production. In summary, this dissertation explores the use (and abandonment) of organic certification within the larger context of development and capacity building in Jordan. In order to explore how value is being created in new ways, the three empirical chapters examine extra virginity, organic certification, and women’s rural organizations. By looking beyond a singular commodity chain, this dissertation examines the processes through which institutional assemblages are formed and destabilized. Therefore, each of the three empirical chapters covers a different aspect of the institutions that are defining value within the larger network of the olive industry. This approach will further our understanding of how quality and conventions function in systems under transition. (Higgins, Dibden, and Cocklin 2008a). Together these findings provide a broad picture of efforts in Jordan to improve and expand the Jordanian olive oil industry. A large aspect of this effort is to produce exportable olive oil. While only a small percentage of producers are exporting, governmental and development networks want to build the capacity of the olive industry so that more farmers are producing to international standards. Through this broad initiative, traditional ideas of quality and the best practices of production are being challenged. These shifts create new networks and products through which rural producers try to capture value. While the overall ramifications of this shift for the average farmer are small now, with further government standardizing, production and its associated social relations could be significantly changed. The traditional farmers who were able to sell within their personal networks may lose their ability to sell flexibly, and simultaneously larger irrigated producers may flourish, having larger environmental impacts.
10

“BEYOND SISTERHOOD THERE IS STILL RACISM, COLONIALISM AND IMPERIALISM!” NEGOTIATING GENDER, ETHNICITY AND POWER IN MADAGASCAR MANGROVE CONSERVATION

Lefèvre, Manon 01 January 2018 (has links)
Understanding women’s experiences of mangrove forest conservation in the Global South is important because mangrove forests are a crucial defense against climate change, and are also increasingly the targets of global climate change policies. The intervention of postcolonial feminist theory combined with feminist political ecology has the potential to bring forward women’s seldom-heard experiences of climate change in these valuable ecosystems. This work supports previous feminist political ecology scholarship focused on understanding women’s complicated relationships to the environment and the gendered effects of climate change policies, while challenging dominant conservation discourse around women as a monolithic group. This thesis focuses on women living in Madagascar’s largest mangrove, particularly under current mangrove reforestation efforts and emerging blue carbon climate change policies. This project explores how the women in this mangrove forest are situated along axes of power differently, the implications of social divisions for conservation, and the ways in which current mangrove conservation projects reproduce power relations in the mangrove by failing to recognize difference.

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