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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.
21

The impact of ecosystem services knowledge on decisions

Posner, Stephen Mark 01 January 2015 (has links)
The need to protect diverse biological resources from ongoing development pressures is one of today's most pressing environmental challenges. In response, "ecosystem services" has emerged as a conservation framework that links human economies and natural systems through the benefits that people receive from nature. In this dissertation, I investigate the science-policy interface of ecosystem services in order to understand the use of ecosystem service decision support tools and evaluate the pathways through which ecosystem services knowledge impacts decisions. In the first paper, I track an ecosystem service valuation project in California to evaluate how the project changes the social capacity to make conservation-oriented decisions and how decision-makers intend to use ecosystem services knowledge. In a second project, I analyze a global sample of cases and identify factors that can explain the impact of ecosystem services knowledge on decisions. I find that the perceived legitimacy of knowledge (whether it is unbiased and representative of many diverse viewpoints) is an important determinant of whether the knowledge impacts policy processes and decisions. For the third project, I focus on the global use of spatial ecosystem service models. I analyze country-level factors that are associated with use and the effect of practitioner trainings on the uptake of these decision support tools. Taken together, this research critically evaluates how ecosystem service interventions perform. The results can inform the design of boundary organizations that effectively link conservation science with policy action, and guide strategic efforts to protect, restore, and enhance ecosystem services.
22

A Systems Approach to Ecological Economic Models Developed Progressively in Three Interwoven Articles

Uehara, Takuro 01 January 2012 (has links)
My dissertation develops and analyzes ecological economic models to study the complex dynamics of an ecological economic system (EES) and investigate various conditions and measures which can sustain a developing economy over the long term in view of resilience and sustainability. Because of the intrinsic complexity of the system, I take a systems approach, using economics as the foundation for the basic structure of an ecological economic model, and system dynamics as the method to build and analyze such a complex ecological economic model. Throughout my dissertation, the model developed by Brander and Taylor (1998) is adopted as a baseline model (henceforth the BT model). The BT model explains population-resource dynamics and is characterized as a general equilibrium version of the Gordon-Schaefer Model, using a variation of the Lotka-Volterra predator-prey model. The findings are presented as three articles. The first article provides a comprehensive analysis of the BT model and its descendants, to elicit directions for further research, including population growth logic, substitutability, innovation, capital accumulation, property rights and institutional designs, and modeling approach. The second article extends the BT model to study the resilience of an EES reflecting three key issues in modeling such systems: 1) appropriate system boundary, 2) non-convexity of ecosystems, and 3) adaptation. The article discusses two types of thresholds: the ecological threshold, a threshold for an ecological system independent of economic systems, and the ecological economic threshold, a threshold for an EES. The latter is often different from the former and is highly dynamic and context dependent. The third article is another extension of the BT model to study the sustainability of an EES by implementing the suggestions made by the first article except for property rights and institutional designs. The main focus is on the impact of endogenous innovation regarding input substitutability on the system sustainability. The main finding is that improvement in the input substitutability, ceteris paribus, may not contribute to sustainable development despite its contribution to expanding the economy. However, it could be possible for susbstitutability improvements to contribute to sustainable development when combined with other specific types of technological progress.
23

Financial Statement Disclosure of Carbon Footprint Costs in the Airline Industry

Tuck-Riggs, Carol Anne 01 January 2015 (has links)
Unaccountable corporate polluters profit short term at the expense of global economic sustainability. The purpose of the study was to determine if carbon dioxide (CO2) penalties on the airline emissions would result in financial statement disclosure and emission mitigation. Contributing to environmental accounting, the study was based in corporate social responsibility with a conceptual framework based on economically-centered CO2 studies. A random sample of 69 global airlines, taken from the International Air Transport Association (IATA) and the International Civil Aviation Organization (ICAO) memberships, was stratified between EU bound and non-EU bound airlines. The research questions explored (a) the frequency mean differences in disclosed CO2 costs between the strata based upon the European Union's environmental trading scheme (EU-ETS) and (b) whether international financial reporting standards (IFRS) influenced the financial statement reporting of CO2 emissions costs. Financial statement data were analyzed in a 3-year longitudinal, ex-post, quasi-experimental, repeated measures factorial ANOVA and ANCOVA, pretest-posttest control group design. The results showed significant CO2 disclosure differences between the experimental (EU bound) airlines and control group (non-EU) airlines and for those airlines with IFRS prepared statements. These results should convince accounting practitioners that the quantification and reporting of greenhouse gas pollution can become the catalyst for improved operations and commercial sustainability. Positive social change to mitigate anthropogenic pollution should result and should promote normative accounting practice to hold those responsible to a higher global accountability.
24

Analysis of Fresh Water Resources at the Line Hole Well Field, San Salvador Island, the Bahamas

Russell Jr., Scot Allan 01 May 2010 (has links)
A major economic constraint in the Bahamas, and other small carbonates islands world-wide, is the lack of fresh water resources. To combat these socio-economic problems on San Salvador Island I sought to gain a more detailed understanding of the extent, behavior, and controls on the island’s fresh-water lens. DC electrical resistivity tomography and time-series geochemical data are used to study the fresh water lens at the Line Hole well field. Electrical Resistivity profiles are used to image the extent of fresh water resources. Time-series geochemical data provide information on the behavior of the fresh water resources as a function of time. The inversion models of the electrical resistivity profiles illustrate a fresh water lens less than 3 meters thick on average. The mixing zone is diffuse in nature, and substantially thicker than the fresh water lens. The geochemical results corroborate the fresh water lens dimensions predicted by the electrical resistivity model. In addition, mixed semi-diurnal and spring/neap tidal cycles are the primary control on the water level. Statistical analysis of specific conductance and temperature illustrate a positive and negative correlation with water level, respectively. Analysis of precipitation with respect to water level and geochemistry indicate low effective recharge rates during the period of study. The current state of the water resources at the Line Hole well field is strained. Despite moderate levels of freshening since the termination of pumping in December 2006; the system continues to be in a state of disequilibrium. The problem is compounded by abnormal thickening of the mixing zone due to communication of the well field with the ocean, and a limited volume of fresh water. In conclusion, the two techniques used in conjunction provide a non-invasive method of estimating fresh water resources in this type of setting. Conversely, the high RMS and L2 values for the electrical resistivity models and limited time-series data create a high level of uncertainty in the interpretation of results.
25

Economie écologique des ressources marines : Le cas de la pêcherie crevettière guyanaise / Ecological economics of marine resources : The case of the french guiana shrimp fishery

Diop, Bassirou Masseck 02 December 2016 (has links)
L'objectif de cette thèse a été de comprendre le fonctionnement économique des pêcheries et de proposer des politiques de gestion des ressources halieutiques. L'attention a été portée essentiellement sur la pêcherie crevettière guyanaise. Une première analyse a été effectuée à partir d'une base de données historique. Les premiers constats ont été que cette pêcherie a été marquée par une forte diminution de son stock, de son effort, de sa production, ce qui a conduit à la fermeture de certaines entreprises. Les premiers résultats ont permis de comprendre que la production de cette pêcherie est fortement dépendante du stock et que la forte diminution de ce dernier n'est pas liée à la surpêche. En effet, malgré une baisse considérable de l'effort de pêche et du prélèvement, le stock a continué de s'effondrer, suggérant ainsi que d'autres facteurs peuvent être mis en cause. En particulier, la zone de pêche est caractérisée par un environnement amazonien avec une mangrove importante et de nombreux cours d'eau. L'intégration de la mangrove dans l'analyse, qui a pourtant connu une diminution de sa surface dans les années 90, n'a pas permis d'expliquer l'effondrement du stock observé. Cependant l'intégration d'autres facteurs comme le débit des fleuves et la température de surface de l'océan ont permis de mieux comprendre la chute du stock dans cette filière. La pêcherie crevettière guyanaise semble en effet fortement impactée par le changement global, notamment l'augmentation de la température des eaux dans les zones de prélèvement. De surcroît, le dernier chapitre suggère que certains phénomènes endogènes à la pêcherie, comme les effets de congestion entre les navires de pêche, rendent l'ensemble de la pêcherie plus sensible à des chocs exogènes technologiques, économiques ou biologiques, en amplifiant l'impact de ces derniers sur les décisions optimales des entreprises concernant l'effort de pêche. Afin de préserver la pêcherie crevettière en Guyane française, il apparaît donc essentiel d'essayer de limiter, dans la mesure du possible, les sources du changement climatique, au lieu de modifier profondément les pratiques économiques du secteur. / The objective of this thesis was to understand the economic behavior of fisheries and to propose resource management policies. The focus was mainly on the French Guiana shrimp fishery. First an initial analysis will be performed on a historical data basis. Initial findings have showed that this fishery was characterized by a strong decrease in its stock, its effort, its production and lead to the closure of some companies. The results have helped also to understand that the production in this fishery is highly dependent on stock and the decrease of the stock is not related to overfishing. Indeed, despite a considerable decline in fishing effort and production, the stock continued to slump suggesting that other factors may be involved. In particular the fishing zone is characterized by an Amazonian environment with significant mangrove and many rivers. The integration of mangrove in the analysis, which shows a decrease in its surface in the 90s did not explain the collapse of the stock. However, the integration of other factors such as rivers and sea surface temperatures have increased understanding of stock depletion in this sector. The French Guiana shrimp fishery is highly influenced by global change, notably increasing in temperature. Moreover, the last chapter suggests that some endogenous phenomena in the fishery, like the congestion effects between fishing vessels, make the whole fishery more sensitive to technology, exogenous economic or biological shocks, amplifying their impact on the optimal business decisions regarding fishing effort. In order to save the French Guiana shrimp fishery, it appears therefore crucial to try to limit the sources of climate change instead of deeply modifying economic practices in this sector, which may lead to misunderstandings by fishermen and local political conflicts.
26

An Economic Valuation Analysis of Buccoo Reef Marine Park, Tobago, West Indies

Da Costa, Dionne J 10 November 2010 (has links)
The purpose of this study was to evaluate tourism capacity, the effectiveness of the management plan and the visitors’ willingness to pay (WTP) for increased conservation effort in the Buccoo Reef Marine Park (BRMP) in Tobago. Non-market contingent valuation was applied to estimate tourists’ WTP, using the data from a survey of 164 tourists. Local residents and government agencies were consulted to evaluate the management plan and the tourism capacity. Eighty-eight percent of local residents stated that the park was not well managed and that they lacked trust in the park agency. The density of tourists was 67-97% more than socially acceptable crowding norm. The tourists were willing to pay an additional entry fee of US$11.72 per person, which would generate additional revenue for the park management. In conclusion, the BRMP management needs modification in order to increase stakeholders’ trust, reduce tourists crowding intensity, and generate additional user-based revenue.
27

SPATIO-TEMPORAL ASSESSMENT OF HEADWATER STREAMS IN THE SAN BERNARDINO NATIONAL FOREST

Mora, Jose Angel 01 December 2019 (has links)
As the demand for freshwater resources increases due to increasing human populations, degradation of available resources, and climatic changes it will become increasingly important to understand the factors that impact the physicochemical characteristics of surface water resources over space and time. This study assessed a headwater stream over the course of a year in the San Bernardino National Forest that serves as both surface and groundwater resources for the Santa Ana River Watershed region, the largest and most populated watershed in Southern California. Streams were monitored bi-weekly during dry periods and weekly during wet periods from April 2018 through April 2019 for dissolved oxygen (DO), flow rate, temperature, conductivity, turbidity, pH, nitrate (NO3-), and ammonium (NH4+) with additional lab assessments for total dissolved solids (TDS), E. Coli (EC), and total coliform (TC). Findings illustrated that across the study sites NO3-, NH4+, and TDS exceeded federal and regional water quality standards for a majority of the sampling events (>60 percent). Additionally, NO3-, DO, and flow rates were elevated in the wet season, while conductivity, NH4+, TDS, pH, TC, and EC were elevated during the dry season.
28

Three essays on taxation and land use change

Templeton, Joshua J. January 2004 (has links)
No description available.
29

Sustainability with Globalization: An Unsustainable Proposition

Reader, Daniel B. 01 August 2006 (has links)
Globalization is recognized as a world-encompassing phenomenon, even as its benefits are debated. Sustainability, the capacity to maintain high standards of living through generations, is at stake. This paper examines the problems of sustainability with globalization from several perspectives. High statistical correlation between indices of globalization and environmental degradation (r2 = 0.977, p < .001) is found using multi-dimensional scaling software. The socially destabilizing, culture flattening effects of globalization are examined, and the terms ‘nationalism’ and ‘terrorism’ are defined. On the basis of its medial position among the indices of both globalization and environmental degradation, Chile is explored in a case study of the interaction. Conclusions regarding Chile’s vulnerabilities are reached, and the country’s environmental, social, and economic ‘weak spots’ are identified. The ethical positions of globalization and sustainability are considered, and the conclusion that there is very little that can be done to alter the nature of the interaction is drawn. It is suggested that globalization minimizes the prospects of success in efforts toward sustainability by maximizing vulnerabilities among sustainability’s components.
30

Factors Affecting Wood Fuel Consumption and Environmental Impacts in Warren County, Kentucky

Vann, Barry 01 August 1990 (has links)
The purpose of this research is to identify factors that contribute to wood fuel consumption as a space heating source and estimate a county-wide proportion for wood fuel consuming households. In addition, environmental problems associated with deforestation such as erosion and loss of wildlife habitat are delineated; moreover, air pollution resulting from wood fuel emissions are discussed. An exhaustive literature review provided the basis for the study. Data on Warren County wood fuel consumption patterns were derived from a mail survey. Proportion estimates were tested by using a classical two-tail test of hypothesis. Subsequently, factors were identified and used in a multiple regression analysis. The study found that low income households equipped with electric space heating systems located in rural areas are the most wood intensive. Unlike homes equipped with other alternate heating systems, electric space heat equipped households tend to consume wood fuel proportionally to income. The study also found that 26.3 percent of single family residences in the county use wood for space heating.

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