• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 47
  • 4
  • 4
  • 1
  • 1
  • Tagged with
  • 136
  • 136
  • 80
  • 56
  • 52
  • 48
  • 48
  • 48
  • 48
  • 42
  • 38
  • 36
  • 35
  • 23
  • 22
  • 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

Food and Fashion : Water Management and Collective Action among Irrigation Farmers and Textile Industrialists in South India

Blomqvist (Jonsson), Anna January 1996 (has links)
In recent years, much ofthe political debate in the West, East aud South has focused on the decentralization of responsibilities from the state to private enterprises and NGOs. But what potential is there for local communities to create their own govenlance structures able to deal with issues up till recently seen as the responsibility of the state? In this thesis, answer to this question is sought by analyzing two case studies from the semi-arid Coimbatore-region in South India from an institutionai perspective. One case concerns the efforts to involve farmers in irrigation water management in the Lower Bhavani Project, while the other focuses on the pressure on textile industrialists in Tirupur city to collectively treat their polluted effluent water. In both cases, the new distribution ofresponsibilities required that groups ofwater users would succeed in establishing new entities for collective action among themselves strong enough to prevent free-riding on a massive scale. Overcoming three main obstacles proved crucial in this process; meeting coordination costs, re-defining the notion of free-riding among resource users, and meeting motivation costs. Factors both within and outsicte the loeal community affected the degree ofsuccess. The distribution and lise of economic, moral and physical power between various actors and the interconnectedness between local and external institutions proved crucial for the establishrnent oflocal govemance stmctures. Moreover, the historical relation between the respective user group and the state has to a large extent affected the goals and strategies oflocal entities of eolleetive action. Clearly, resource management problems at localleve1 can not be solved by simply decentralizing responsibilities from the state to groups ofresource users. Rather, the state could playan important role by initiating, supporting and directing slich local entities of collective action.
5

Jean-Jacques Rousseau and the Tension between Nature and Society

Woolfson, Tony 09 1900 (has links)
<p>This thesis isconcerned with Jean-Jacques Rousseau's treatment of the effect of political actions on the human problem. Four emphases in that treatment are considered.</p> <p> In the first place, Rousseau is concerned about what can be called a tension between nature and society, a tension which is basic to the human situation as he sees it. He wants to distinguish between good nature and bad society and between a good, natural self and a bad, social self.</p> <p>In the second place, closer scrutiny reveals that the tension between nature and society hinges on the problem of passion. Rousseau wants further to distinguish between good, natural passions and bad, social passions, and the political problem is always and everywhere the same: how to control the bad, social passions.</p> <p>In the third place, there is a dialectical unity in Rousseau's treatment of the tension between nature and society. Contrary to many interpretations, he does not treat nature and society as concrete abstractions but only as hypothetical abstractions. His writings are consistent; he is both idealistic and realistic, theoretical and practical, optimistic and pessimistic.</p> <p>In the fourth place, whether Rousseau is talking about individuals or societies there is a continuing emphasis on an organic cycle of life and death. An ironical situation develops in respect of political actions. that affect the tension between nature and society. Political actions have to be as natural as possible, but they confront nature as limit, in the form of a natural tendency on the part of individuals to place their own interests ahead of those of their fellows. Rousseau envisions no way out of that vicious circle, and we are, therefore, faced with the prospect of a never-ending cycle of life and death of all organic bodies, including bodies politic.</p> <p>Those four emphases inform the structure of this thesis. The thesis is divided into a series of chapters dealing with different aspects of the tension between nature and society. The thesis begins with a discussion of how Rousseau himself dealt with the problems that he faced in his life, given that he considered himself an exemplar of what it meant to be both natural and human. The thesis then looks at the tension between nature and society viewed as hypothetical abstractions, after which the tension is considered from an historical perspective. </p> <p>The centrepiece of the thesis consists of a discussion of how political actions can affect the tension between nature and society, through communitarian and egalitarian politics. The cycle is completed by showing why, in the long run, all bodies politic are bound to decay and die, bearing in mind, however, that regeneration is always possible.</p> / Thesis / Doctor of Philosophy (PhD)
6

Irrigation sector development in Punjab ( Pakistan) : Case Study of district Sargodha

Hayat, Ansar January 2007 (has links)
<p>Pakistan is a densely populated country; and its population is increasing rapidly. More than fifty percent of population is living in rural areas and is related to agricultural sector. Punjab is the most populated province of Pakistan. Irrigation system of Punjab is not very developed. The present irrigation system is almost hundred year old. The management of existing irrigation system is a big challenge. With increase in population, load on existing irrigation system is also rising and situation is presenting serious problems.</p><p>This report addresses main problems related to management of irrigation system in district Sargodha of Punjab province of Pakistan. The problem with management of existing irrigation system includes social as well as technical problems. This report also discusses loss in agricultural production due to mismanagement of irrigation system. Further, report also suggests possible solutions for the management of irrigation system. These solutions take into account reforms in social sector as well as introduction of new technology.</p><p>For the assessment of report, past research related to management of irrigation system in Indus basin has been studied. This research also includes ideas of previous researchers about management of irrigation system and then we try to conclude possible solutions for better management of irrigation system in area.</p>
7

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.
8

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.
9

AUDIENCE RESPONSE TO THE NATURE/SOCIETY BINARY IN KUROSAWA’S DERSU UZALA: AN OBSERVATIONAL ONLINE ETHNOGRAPHY

Sharp, Laura L. 01 January 2013 (has links)
Geographers researching cinema have predominantly been interested in how geographic meaning is constructed and negotiated within film, but have been less productive in accounting for how these constructs are received by viewers. Using the method of observational online ethnography, I therefore investigate how fans in online reviews have interpreted the nature/society binary in the film Dersu Uzala. Working from a social constructionist view of nature I begin by deconstructing the binary as it appears in Dersu Uzala before proceeding to illustrate the way this constitutive absence is made up for by the visuality of the film’s landscapes and techniques of geographic realism. Turning to the fan reviews I find that, rather than challenge the historical and constructed division between nature and society, many fans accept the binary as inevitable and consistent with their ideas about contemporary reality. More than passive consumption however, this concurrence is actively rearticulated in the ways that the fans incorporate the binary into their own lives and in the new discursive practices of the internet. In so doing I make headway into the exploration of audience analysis by geographers and continue to advance geography’s foray into cultures of the internet.
10

Irrigation in Africa : Water conflicts between large-scale and small-scale farmers in Tanzania, Kiru Valley

Said, Samy January 2006 (has links)
<p>This paper deals with relationship between irrigation and agriculture and conflicts within an irrigation system and as well between other stakeholders concerning the water. Irrigated lands are up to 2.5 times more productive compared to rain-fed agriculture. They are important element in the agriculture sector in Sub-Saharan Africa, and have been favoured by governments and donor agencies for their high rate of return. Without proper technical equipments or support negative impacts on the environment are linked to irrigation activities. Furthermore, a case study was made in Tanzania, Kiru Valley, regarding the tension between big scale and small-scale farmers as result from the water decline. The results demonstrate that the institutions do not have the power to solve the conflict. It is difficult to define the different stakeholders and the boundaries of the area that affect the amount of water in the valley.</p>

Page generated in 0.0754 seconds