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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.
821

Sediment Removal from the San Gabriel Mountains

Ferguson, Mary C 01 May 2012 (has links)
The issue of sediment removal from the San Gabriel Mountains has been a complex issue that has created problems with beach replenishment, habitat destruction and the need to spend millions of dollars at regular intervals to avoid safety hazards. Most recently 11 acres of riparian habitat, including 179 oaks and 70 sycamores, were removed for sediment placement. Other sites including Hahamongna Watershed Park and La Tuna Canyon also face a similar fate. This thesis questions: How did we get to this point of destroying habitat to dump sediment which is viewed as waste product? What are the barriers for creating long term solutions and progressive change? What are some other options? And how should we move forward? The issues with sediment management have stemmed from regulatory compliance issues, adversarial relationships within agencies and among NGO's and the public, and the lack of a comprehensive long-term plan to prevent further habitat loss and other sediment removal issues. A recommendation includes looking at a community forestry model to include a wide cross-section of the community, NGO's and government agencies to come up with a long term comprehensive and progressive solution.
822

A Survey of Drought Impacts and Mitigation Planning in Kentucky

Bergman, Crystal Jane 01 August 2009 (has links)
Drought is a well-known and costly climate-related natural hazard. Unlike other climate-related natural hazards, droughts are usually long in duration and may cover a large region, the physical boundaries of areas affected by drought are sometimes arbitrary, and the impacts are sometimes difficult to identify. Climate records since 1895 show that drought has occurred periodically in Kentucky. The drought of 2007 was the most recent drought to affect Kentucky and is the primary focus of this research. The purpose of this research is to identify impacts of drought and potential vulnerabilities to various drought impact sectors in Kentucky so that policymakers can develop a drought plan that addresses these vulnerabilities and emphasizes mitigation efforts. An historical analysis of drought was provided for the following droughts that occurred in Kentucky: 1930-31, 1940-42, 1952-55, 1987-88, and 1999-2001. A more indepth analysis of the development and impacts of the drought of 2007 was conducted. Weekly drought reports from the drought of 2007 that were published by the Kentucky Division of Water were used for analysis.The reports discussed streamflows, PDSI values, precipitation deficits, lake levels reports from the U.S. Army Corps of Engineers, and other information that documented the progress of the drought. Impacts caused by the drought of 2007 were identified mostly through news reports. Agriculture and water supplies were determined to be most impacted by drought; therefore, two separate surveys (one regarding drought impacts on agriculture in 2007, the other regarding drought impacts on water supplies in 2007) were created to increase the understanding of how the drought of 2007 affected agriculture and water supplies in Kentucky. Other impacts from the drought of 2007 that were studied include impacts on recreation and tourism, the number of fires and wildland fires, plant and animal species, and small businesses. It was found that droughts that have affected Kentucky have originated in all directions and have spread northward, southward, eastward, and westward into Kentucky. The temporal scale of these droughts has also varied. Impacts caused by the drought of 2007 in Kentucky were very similar to impacts caused by historical droughts. However, the documentation of drought impacts that occur in Kentucky needs improvement. Agricultural impacts are documented better than any other impact, while impacts on water supplies, recreation and tourism, the occurrence of wildland fires, plant and animal species, and small businesses are not as well documented. It is recommended that conducting an extensive analysis of how various sectors are vulnerable to drought in Kentucky and educating the public on the importance of drought awareness should be addressed by policymakers involved in the development of Kentucky’s state drought plan.
823

Managing relationships, learning and demands in protected areas : a social systems analysis.

Nkhata, Bimo Abraham. January 2007 (has links)
This thesis seeks to contribute to the improved understanding of social systems analysis in management effectiveness research on protected areas. It develops and applies propositions for incorporating the analysis of social systems into management effectiveness research. The propositions are designed as theoretical constructs which represent some aspects of social reality in protected area management. They signify an organized way of thinking about the social domain of protected area management. It is argued that an analysis of management effectiveness must recognize the need to take into account the inherent interactive nature of the connections among three variables, relationships, learning and demands. It is suggested that the three variables do not exist in isolation, but are interconnected and exert influence on each other. The interactions among the variables provide this study with a conceptual structure for analyzing the social domain of protected area management. The thesis conceives the management of relationships as a behavioral process in which protected area management agencies influence the decisions and actions of other parties, and vice versa, over a period of time in order to advance shared interests. The effectiveness of relationship management depends on integrated learning, a collective process of managing information in a timely manner so as to enhance the responsiveness of social actors involved with protected areas. Demand management is viewed as a social process in which protected area management agencies develop timely and defensible responses to current and emerging demands from stakeholders. The management of demands is expressed through relationship management and integrated learning. Important in this context is the capability of social actors to cope with complexity, change and surprises. The thesis should be seen as a theoretical premise that focuses on the learning competence of social actors by aligning and fostering their ability to respond timely to the ever-changing demands on protected areas through the effective management of relationships. It should be viewed as making a contribution to the move in protected area management towards developing learning organizations and institutions through a systems approach. This should be interpreted as enhancing learning about the human dimensions of protected area management. And more specifically, effective learning generates timely responses in the management of demands and relationships. The implications of failure to respond quickly enough are epitomized in a number of South African examples such as rivers that stop flowing and conflicts over resource use. The thesis makes a contribution to management effectiveness research by examining in some important ways why research should not be determined solely by biophysical components, but should be extended to the broader social issues that define the nature and quality of management. It is argued that a deep appreciation of management effectiveness requires an understanding of relationships, learning and demands to provide a foundation for systemic social analyses. The thesis illustrates why a behavioral approach to relationships theory provides a foundation for resilient social relationships in collaborative processes. It shows why the establishment and maintenance of an integrated learning system take place in a complex context which links elements of governance learning and management learning. It also evinces why protected area management agencies have to incorporate mental models into adaptive management of demands. These insights imply that the opportunities for effective protected area management are largely contingent on systemic insights into the underlying social structures and processes responsible for emergent problems. By exposing the insights, research on management effectiveness is poised to take new direction. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
824

Essais en économie de l’environnement et des ressources naturelles sous incertitude

Kakeu Kengne, Justin Johnson 08 1900 (has links)
Cette thèse comprend trois essais en économie de l’environnement et des ressources naturelles sous incertitude. Le premier essai propose un modèle de jeu différentiel qui analyse la pollution globale à travers la quête à l’hégémonie politique entre pays. Le second essai utilise des données boursières pour estimer une version stochastique de la règle de Hotelling et ainsi inférer sur le rôle des ressources naturelles non renouvelables dans la diversification du risque. Le troisième essai montre comment la prise en compte des perspectives futures modifie la règle de Hotelling dans un contexte de diversification du risque. / My thesis is composed of three essays on environmental and natural resource economics under uncertainty. The first essay proposes a differential game analysis of the quest for hegemony among countries as a generator of global pollution. The second essay uses stock market data on market capitalization to estimate a stochastic version of the Hotelling rule of exhaustible resource exploitation and uses it to infer on the riskiness of investment in nonrenewable resources and its effect on the resource price paths. The third essay shows how uncertainty about future prospects modifies the Hotelling rule in a context of risk diversification.
825

Water Quality Trading Markets for the Kentucky River Basin: A Point Source Profile

Childress, Ronald, Jr. 01 January 2012 (has links)
This study assessed the feasibility and suitability of a Water Quality Trading (WQT) program within the Kentucky River Basin (KRB). The study’s focal point was based on five success factors of a WQT program: environmental suitability, geospatial orientation, participant availability, regulatory incentive, and economic incentive. The study utilized these five success factors, geographical characteristics, and Discharge Monitoring Reports (DMR) to assess the feasibility of a WQT program. The assessment divided the KRB into five eight digit Hydrologic Unit Codes (HUC), North, Middle, and South Fork, Middle Basin, and Lower Basin, to determine regional impacts caused by the nutrient PSs. Individual nutrient profiles were generated to show the number of point sources (PS) operating in the KRB, their geospatial orientation to one another, and their permitted nutrient limits and nutrient discharges in form of total phosphorus (TP), total nitrogen (TN), and total nitrogen (as ammonia) (TA). Findings suggest trading is highly unlikely for TP and TN PSs due to the lack of regulatory standards, limited number of TN and TP PSs, and an inadequate demand for offset credits. Trading is also unlikely in all the HUC 8 watersheds except for the Lower Basin due to the lack of nutrient impaired waters. Key Words: Point Source, Non-Point Source, Water Quality Trading, TMDL, Impaired Waters
826

Making Sense of Environmental Values : Wetlands in Kenya / Att förstå olika miljövärden : Våtmarker i Kenya

Billgren, Charlotte January 2008 (has links)
En av de viktigaste frågorna i världen idag är naturresurshantering. Med en väx-ande befolkning och hoten från klimatförändringar kommer förvaltningen av jordens naturresurser bli än viktigare, såväl för dagens generation som kommande generationer. En viktig aspekt när det gäller naturresurshantering är hur människor uppfattar och värderar naturen. För att komma närmare dessa miljövärden har ett flertal olika vetenskapliga tillvägagångssätt föreslagits. Den här avhandlingen undersöker hur det är möjligt att närma sig miljövärden under olika omständighe-ter och utifrån olika behov. Detta görs genom att undersöka hur olika teorier har använts, och kan användas, avseende olika våtmarker i Kenya. I utvecklingslän-der har naturresurser, teoretiskt sett, ett högre värde eftersom fattiga människor till en högre grad är direkt beroende av naturresurser och ekosystemtjänster. Ut-gångspunkten i denna avhandling är sex våtmarksområden i Kenya under olika förvaltning och med ett flertal, både aktuella och potentiella, användare. I av-handlingen undersöks hur lokalsamhället, myndigheter, industrier och turister uppfattar och värderar våtmarkerna. Genom att applicera ett arenaperspektiv, som betonar vikten av tvärvetenskap, diskuteras i avhandlingen det ekonomiska värdet av miljön för att sedan applicera andra metoder såsom emergy analys, stakeholder analys, kulturteori och riskanalys för att bredda och berika värderingen av miljön. / One of the most important issues in the world, both for present and future genera-tions, concerns natural resource management. With a growing global population and the threat of climate change, issues relating to natural resource management will grow in importance with time. One fundamental aspect of natural resource management is how people perceive and value the environment. The value that is ascribed to natural resources will be one of the determinants in the choices that people face in regards to their management. A wide range of approaches have been suggested to approach environmental values. This thesis focuses on analys-ing the assessment of environmental values under different circumstances and needs. This is done by exploring the ways various theories have and can be used to approach natural resource valuation in different wetland management situations in Kenya. In the developing world the value of natural resources can, theoreti-cally, be seen as even higher than in the developed world, due to poor peoples’ direct dependency on their natural resources and the ecosystem services and goods that they provide. The point of departure in this thesis is six wetland areas with different management strategies and with multiple users. It examines how local communities, governmental authorities, industries and tourists perceive the value of the wetlands. By applying an arena perspective, that emphasises the need of interdisciplinarity, this thesis discusses the economic value of the environment and applies other methods such as, emergy analysis, stakeholder analysis, cultural theory and risk analysis, to enrich the valuation of environment.
827

Effects of sheep, kangaroos and rabbits on the regeneration of trees and shrubs in the chenopod shrublands, South Australia

Palisetty, Raghunadh January 2007 (has links)
After European settlement, Australian rangelands especially in South Australia underwent significant changes because of the main land use of pastoralism. Many studies have revealed that the plant communities are negatively effected by herbivory mainly by sheep. The main aim of this study is to separate the different effects of sheep, rabbits and kangaroos. This was examined by survey supported by experimental and modelling research. A 32,000 km² area previously surveyed by Tiver and Andrew (1997) in eastern South Australia was re-surveyed to monitor populations of perennial plant species at sites of various intensity of grazing by sheep, rabbits and kangaroos (goats populations are low in the study area), the most important vertebrate herbivores. Plant population data were collected in both sheep paddocks and historically ungrazed by sheep (road reserves) by using the Random Walk method and analyzed using Generalized Linear Modelling (GLM) to separate the effects of sheep and rabbits on plant regeneration and their regeneration in response to grazing. These data were also compared to similar data collected by Tiver and Andrew in 1992 (1997) to ascertain if the reduction in rabbit numbers through introduction of RCV had allowed increased regeneration. Regeneration of many species inside paddocks were negatively affected and species in roadside reserves neither did not significantly increase from 1992 to 2004. However, some species showed increase of populations in spite of sheep grazing, with some species being less susceptible than others. This research also indicates kangaroo grazing impact on some plant species. Reduction in rabbit numbers following the 1995 release of calicivirus has not been effective in restoring regeneration. Another experiment was conducted at Middleback Field Station near Whyalla to identify herbivore grazing pressure on the arid zone plant species Acacia aneura using unfenced, sheep fenced and rabbit fenced grazing exclosures. This experiment was set up with seedlings in exclosures, ten replicates of each treatment, at plots four different distances from the watering point to identify the survivorship of seedlings. Data were collected by recording canopy volumes of seedling over an 18 month period and analyzed by Residual Maximal Likelihood (REML). Seedlings both near and far from the watering point were severely effected by large herbivores, either sheep, kangaroos or both, and in a separate experiment kangaroo grazing effects on the seedling were also identified. Seedlings browsed by the rabbits were recovered better than the seedlings grazed by the large herbivores. Decreasing kangaroo activities has been noticed when the rabbit movements increased. Computer modelling was conducted to predict the future plant population structure over 500 years using a matrix population model developed by Tiver et al. (2006) and using data collected in the survey as a starting point. Extinction probabilities of populations of Acacia aneura near watering points, far from watering points and under pulse grazing scenarios were compared. Sheep grazing was found to cause eventual extinction of populations in all parts of sheep paddocks. Together, the results indicate that sheep are the major herbivore suppressing regeneration of perennial plant species. Kangaroo and rabbits have an identifiable but lesser effect. The results have implications for conservation and pastoral management. To achieve ecological sustainability of arid lands a land-use system including a network of reserves ungrazed by sheep and with control of both rabbit and kangaroo numbers will be required.
828

Endogenous development of natural resource management in the communal areas of Southern Zimbabwe : a case study approach

Van Halsema, Wybe 09 1900 (has links)
Despite decades of development efforts to combat desertification processes in southern Zimbabwe, a development deadlock occurs. Using the local knowledge systems as a basis, and making an effort to strategically facilitate the revival of their capacity for checks and balances as a development approach, endogenous development could become more realistic. The actor-oriented RAAKS.methodology offers relevant tools for a case study'in which an insight into the processes of innovation is obtained in order to confirm this. The Charurnbira case study shows that many local interfaces hinder development. Although the facilitation of platform processes could enhance endogenous development, the external environment provides a serious constraint. The method employed did ndt permit broad conclusions, but a deeper examination of recent experiences suggested that by giving local people a greater say in natural resource use, local knowledge could be utilized more effectively and better use could be made of traditional management structures. / Development Administration / M.A. (Development Administration)
829

Natural resource management and local knowledge in transition : an anthropological perspective from the Laka of Mapela

Eckert, Britta 12 1900 (has links)
This study sets out to analyse the relevance of cultural values and perceptions, which form the basis of the "local knowledge" of grassroots people, in the natural resource management of the Laka of Mapela who live in the former Lebowa homeland in the Northern Province of South Africa. Due to the fact that political transitions affect the traditional authority system, it further explores the role of traditional leaders regarding control and decision-making over natural resources as well as the activities of oppositional groups at local level, and their attitudes towards land tenure issues. Natural resource management is approached holistically because, in grassroots perceptions, the natural world does not "stand on its own" and is not dissected into manageable units but forms part of a wider cosmos which is made up of human beings, nature and the supernatural. A happy life of people, fertile soils and rich botanical resources are inseparable from harmony in the cosmos. Misfortune, natural resource degradation and scarcity are consequently explained with a state of flux, or imbalance, in these cosmic relationships which have to be restored by people in order to survive. The general conclusions suggest that these local perceptions of natural resource management cannot be ignored from the development arena as well as by outside scientists and practitioners. Rather, in order to develop more progressive approaches for sustainable management in the former homelands, policies and plans have to be compatible with the worldview of local people to enhance their acceptance and implementation. / Anthropology and Archaeology / D. Litt. et Phil. (Anthropology)
830

HOW DO POST-CONFLICT ENVIRONMENTAL INITIATIVES AFFECT WOMEN'S EMPOWERMENT WITHIN NATURAL RESOURCE MANAGEMENT IN THE SHORT TERM?

Uleviciute, Gertruda January 2018 (has links)
This thesis aims to explain how post-conflict environmental initiatives affect women’s empowerment within natural resource management in the short term. It argues that the lack of causal effect between the variables can be explained by the robustness of patriarchal institutions. Gender-sensitive environmental peacebuilding lacks the strength to counter traditional and well-established formal and informal societal structures. Using a structured focused comparison on Sudan and Democratic Republic of Congo the analysis shows that UNEP Country Recovery Programmes, which are used as an example of the post-conflict environmental initiatives, were unable to change women’s position within natural resource management in the first five years of the establishment. Even though presented theoretical frameworks partially explain the results, more research is needed to draw informed and conclusive inferences.

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