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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.
91

Economic Valuation Of Florida Sea Turtles In Face Of Sea Level Rise

Hamed, Ahmed 01 January 2013 (has links)
Sea level rise (SLR) is posing a great risk of flooding and inundation to coastal areas in Florida. Some coastal nesting species, including sea turtle species, have experienced diminished habitat from SLR. In an effort to assess the economic and ecosystem service loss to coastal areas with respect to sea turtles Contingent Valuation Method (CVM) and Habitat Equivalency Analysis (HEA) were used. The CVM was used to measure the economic impacts of SLR on sea turtles. Open-ended and dichotomous choice CVM was used to obtain the willingness to pay (WTP) values of Florida residents to implement certain mitigation strategies which would protect Florida’s east coast sea turtle nesting areas. The problem of sample selection bias was reduced by surveying residents of two cities that would potentially have varying interest in coastal conservation due to their relative distance from the coast. The hypothetical WTP of Florida households to implement policies designed to protect sea turtle habitat from development encroachment was estimated to be between $21 and $29 per year for a maximum of five years. Characteristics of respondents were found to have statistically significant impacts on their WTP. Findings include a negative correlation between the age of a respondent and the probability of an individual willing to pay the hypothetical WTP amount. Counter intuitively, it was found that WTP of an individual was not dependent on prior knowledge of the effects of SLR on sea turtle habitat. As the level of this awareness increased, the probability to pay the hypothetical WTP value decreased. The greatest indicators of whether or not an individual was willing to pay to protect sea turtle habitat were the respondents’ perception regarding the importance of sea turtle population health to the ecosystem, and their confidence in the conservation methods used. iii Concepts of Habitat Equivalency Analysis were used in order to determine the ecosystem service lost due to SLR. The study area of Archie Carr National Wildlife Refuge (ACNWR) has a continually increasing sea turtle population due to various conservation efforts. However, how the inundation of the coastal area will injure this habitat was assessed, and if mitigation strategies to compensate for the loss are necessary. The carrying capacity (CC) of the refuge was chosen as the metric of the ecosystem service. Using the estimated area of ACNWR and the approximate area needed by a sea turtle to nest, the theoretical number of sea turtle nests possible on the refuge was calculated. This value was then projected to the year 2100 using the sea level rise scenarios provided by IPCC (2007) and NRC (2010). In order to quantify the injury caused by the decrease in the refuge’s CC, the number of sea turtle nests on the refuge was projected to the year 2100 using the data obtained over the past 30 years. The analysis concludes a potential loss of service to be experienced as early as 2060’s due to the carrying capacity of the refuge diminishing with the loss of the habitat due to the increase in the mean sea level.
92

An evaluation of environmental concerns and private land conservation programs

Adhikari, Ram Kumar 01 May 2020 (has links)
Bottomland hardwood forests and pine forests in the southern United States provide valuable ecosystem services such as timber, recreation, wildlife habitat, carbon sequestration, floodwater storage, and sediment and nutrient retention. However, these forest ecosystems are threatened because of intensive forest management, forest land conversion, and urbanization. As private landownership dominates in this region, landowner participation is crucial for success of conservation programs facilitating ecosystem services. This research focused on three different aspects of private land conservation programs. First, it estimated the impact of environmental contextual factors, private land attributes and sociodemographic characteristics on landowner concern about environmental issues. Second, it determined the influence of private land attributes, environmental concerns, frequency of contacts with federal agencies and socioeconomic characteristics on landowner satisfaction with available conservation programs. Third, it estimated the monetary compensation required by landowners to implement conservation practices focused on increasing provision of ecosystem services. Data were collected using a mail survey and from online sources. Data were analyzed using seemingly unrelated regression and logistic regression models. Results indicated that private land attributes, particularly size of agricultural land owned, and landownership goals such as providing ecosystem services and profitability, had a greater magnitude of positive association with landowner concerns about environmental issues than other factors. Similarly, size of agricultural land owned, landownership goals such as profitability and personal recreation, concerns about wildlife habitat losses and frequent contacts with federal agencies were positively related to landowner satisfaction with conservation programs. Landowner willingness to participate in a conservation program was positively related to payment amount, concerns about wildlife habitat losses, frequency of contact with the Natural Resources Conservation Service (NRCS), and education level. Similarly, provision of clean water as landownership objective, concerns about hurricanes and tornadoes, and landowner age were negatively associated with landowner interests to participate in conservation programs. This research also quantified landowner median willingness to accept (WTA) compensation which was $229.98 ha-1 yr-1 for participation in a conservation program related to bottomland hardwood or pine forests. The findings help identify likely participants or landowners for conservation programs facilitating ecosystem services and determine actual conservation costs at a regional level.
93

Creating an interdisciplinary framework for economic valuation: A CVM application to dam removal

Kruse, Sarah A. 05 January 2005 (has links)
No description available.
94

Economic efficiency and income distribution evaluation of toxics and dam removal using contingent valuation

Abdul-Mohsen, Ashraf A. 06 January 2005 (has links)
No description available.
95

Two essays on environmental and food security

Jeanty, Pierre Wilner 30 November 2006 (has links)
No description available.
96

Advances in Applied Econometrics: Binary Discrete Choice Models, Artificial Neural Networks, and Asymmetries in the FAST Multistage Demand System

Bergtold, Jason Scott 27 April 2004 (has links)
The dissertation examines advancements in the methods and techniques used in the field of econometrics. These advancements include: (i) a re-examination of the underlying statistical foundations of statistical models with binary dependent variables. (ii) using feed-forward backpropagation artificial neural networks for modeling dichotomous choice processes, and (iii) the estimation of unconditional demand elasticities using the flexible multistage demand system with asymmetric partitions and fixed effects across time. The first paper re-examines the underlying statistical foundations of statistical models with binary dependent variables using the probabilistic reduction approach. This re-examination leads to the development of the Bernoulli Regression Model, a family of statistical models arising from conditional Bernoulli distributions. The paper provides guidelines for specifying and estimating a Bernoulli Regression Model, as well as, methods for generating and simulating conditional binary choice processes. Finally, the Multinomial Regression Model is presented as a direct extension. The second paper empirically compares the out-of-sample predictive capabilities of artificial neural networks to binary logit and probit models. To facilitate this comparison, the statistical foundations of dichotomous choice models and feed-forward backpropagation artificial neural networks (FFBANNs) are re-evaluated. Using contingent valuation survey data, the paper shows that FFBANNs provide an alternative to the binary logit and probit models with linear index functions. Direct comparisons between the models showed that the FFBANNs performed marginally better than the logit and probit models for a number of within-sample and out-of-sample performance measures, but in the majority of cases these differences were not statistically significant. In addition, guidelines for modeling contingent valuation survey data and techniques for estimating median WTP measures using FFBANNs are examined. The third paper estimates a set of unconditional price and expenditure elasticities for 49 different processed food categories using scanner data and the flexible and symmetric translog (FAST) multistage demand system. Due to the use of panel data and the presence of heterogeneity across time, temporal fixed effects were incorporated into the model. Overall, estimated price elasticities are larger, in absolute terms, than previous estimates. The use of disaggregated product groupings, scanner data, and the estimation of unconditional elasticities likely accounts for these differences. / Ph. D.
97

Integrated scenic modeling of environmentally induced color changes in a coniferous forest canopy.

Clay, Gary Robert. January 1995 (has links)
The relationship between the changes in color values of scenic landscapes, and the corresponding shifts in viewers' preferences to those changed environments, was the focus of the presented research. Color modifications, either natural or based on some human intervention, provide visual clues that an environment has undergone some transformation. These color changes can occur at both the micro and macro scale, can having temporal dimensions, and can be a result of combinations of both physical landscape change, and shifts in an observer's perspective with respect to that landscape. The research reviewed two existing models and related them in an integrated program of scenic change analysis. The first, a bio-physical remote sensing model, identified the relationships between the existing bio-physical environmental conditions and measured color signatures of selected landscape features. The second, a psychophysical perception model, established relationships between the landscape's bio-physical attributes and measured perceptual responses to those environments. By merging aspects of each model, the research related the changing scenic color patterns with observers' responses to those changed environments. The research methodology presented a program of scenic change analysis incorporating several technologies including (1) ground-based biological inventories, (2) remote sensing, (3) geographic information systems (GIS), and (4) computer visualization. A series of investigations focused on landscape scenes selected from a high elevation coniferous forest in southern Utah. Three initial scenic investigations compared (1) the impact of changing view angles on scenic color values, (2) color shifts due to changing sun-illumination angles within a day, and (3) color shifts due to changing biological conditions over a 12-month period. A fourth investigation measured the color changes caused by a spruce bark beetle outbreak, and developed a series of color signatures to simulate the color shifts indicative of an outbreak at different stages of development. These signatures were applied to digitized site photographs to produce a series of visualizations displaying different levels of beetle damage. The visualizations were then applied in a series of perceptual experiments to test the precision and reliability of the visual simulations.
98

The monetary value of marine environmental change

Hasselström, Linus January 2016 (has links)
The marine ecosystems are fundamental for human welfare. A number of current environmental pressures need attention, and the formulation of management strategies requires information from a variety of analytical dimensions. The linkage between environmental change and resulting implications for human welfare is one such dimension. This thesis presents studies on welfare implications from hypothetical future policies which improve the state of the marine environment. The method for these studies is economic valuation. The studied scenarios concern eutrophication in the Baltic Sea (including the Kattegat) and oil spill risk from shipping in the Lofoten-Vesterålen area in the Arctic Barents Sea. The thesis shows that the economic benefits from undertaking policies to improve or protect the marine environment in these cases are substantial and exceed the costs of taking measures. In addition to providing new monetary estimates, the thesis also provides new insights concerning 1) what type of scenario to use when valuing an environmental improvement and 2) whether there may exist trade-offs between precision in estimates and the level of ambition with respect to survey instrument complexity and econometric models when conducting valuation studies. The findings suggest an end of an era for studies in which the environmental change is unspecified or based on a single environmental indicator while the actual consequences of the suggested measures are more multifaceted. In contrast, relevant scenarios to study are well-specified and holistic. The thesis further reveals that it might not always be worth the effort to go for the most advanced scenario presentation or statistically best-fitting model specifications. This is something that needs to be further discussed among practitioners in order to allocate valuation resources wisely and not waste resources on unnecessarily elegant valuation studies. / <p>QC 20161011</p>
99

Utah Boating and Fishing Survey: Applying Contingent Valuation and Travel Cost Methods to Estimate Recreational Values in Northern Utah for the Bear River Water Development Project

Williams, Jeff T. 01 May 1994 (has links)
The intent of this thesis is to compare contingent valuation methods (CVM) and travel cost methods (TCM) to estimate consumer surplus for boaters and anglers in northern Utah. TCM results are about three times that of CVM. Several limitations are noted, specifically that CVM solicits given willingness to pay (WTP for specific reservoir sites. TCM analyzes aggregated trips to reservoirs with a wide array of site characteristics.
100

Use the Contingent Valuation Method (CVM) to study the tourists for Penghu National Scenic Area between 2008 to 2011development plan of the economic effect evaluation.

Jan, Sue-lin 04 August 2007 (has links)
Within these years, in order to effectively arrange the limited resource that the government has owned and been able to allocate, a detailed financial plan and a well-structured evaluation system for any project is essential. Normally the most research topics issued are related to the economic effect of natural resources. In Taiwan, the article about analyzing the economic effect about the tour schemes proposed for the development of National Scenic Area is few and only at the beginning stage and the cause mainly is because of the common property of such schemes, i.e. the involvement of different departments needed. At this situation, effected by the different control froces from a varity of government departments and varied industry structures and developing progress in different areas, it is difficult to clarify and analyze the achievement for each department. Owing to this character, the economic effect related to such development schemes is difficult to conclude and it is even harder to evaluate whether or not the economic benefit is definitely resulted from the improving projects. The research topic is going to comprehend the economic effect caused by the medium-range scheme launched by National Scenic Areas, then is able to propose some feasible items to evaluate the economic effect and collect the figures the Cost-Efficiency Evaluation relaed to the effect. As to the intangible benefit, it is assessed by the Contingent Valuation Method (CVM). The study takes the case of Penghu National Scenic Area to predict the economic effect between 2008 to 2011. From the research, it shows that the figure of Willing To Pay (WPA) among the tourists already visited the Penghu National Scenic Area is NT$6,943 and within 2008 and 2011, after the development implemented, the amount is going to raise to NT$9,638. Based on this raise, the economic revenue would be NT$415,691,000 caculated from the Prediction equation in 2008, NT$428,984,000 in 2009, NT$442,397,000 in 2010 and NT$ 455,933,000 in 2011. Within 10 year of available analytic fixed number of years, the 4-year Net Present Value¡]NPV¡^ ¡]valuta of 2008 year ¡^ will be NT$1,766,586,000 based on the discount rate at 2% and the 4 year Benefit-Cost Ratio, B/C ratio is 3.05>1. From this result, the 2008-2011 development plan itself has demostrated its economic feasibility.

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