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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

Development of a Decision Support Methodology for the Design of Animal Waste Management Strategies to Achieve Regional Environmental Objectives

Anastasiou, Christos Charalambou 03 December 2002 (has links)
Management of waste from confined animal feeding operations is becoming increasingly important. While anaerobic lagoons and sprayfields are currently used for treatment, recent administrative initiatives call for their replacement. This decision has increased the need for characterization of the cost and treatment effectiveness of alternative technologies. However, due to variations in farm characteristics (e.g., size, location), identification of the most cost-effective combination of treatment technologies to achieve collective environmental goals requires an integrated approach (i.e. all combinations of treatment technology alternatives at all farms in a region must be considered simultaneously). The objective of this research was to develop a regional management decision-support framework to assist policy-makers, planners, and farmers in making cost effective lagoon replacement decisions to achieve desired treatment and public protection goals. A major component of the framework is a cost and treatment efficiency assessment tool to evaluate alternative animal waste treatment technologies for individual farms. Outputs from the assessment tool, together with geospatial data, feed into the regional management component of the framework, which consists of several formal optimization techniques that assist in the search for good decisions. Among these techniques are an optimization engine (integer programming) that can be used to find management strategies that meet cost and environmental targets, and a method for efficiently generating alternatives (Modeling to Generate Alternatives (MGA)). The management alternatives have similar cost and environmental performance but may behave differently for unmodeled objectives (e.g., risk or equity). Finally, the regional management framework includes an uncertainty analysis component that allows the evaluation of alternatives while taking into consideration the uncertainty in model inputs. The decision-support framework was demonstrated through an illustrative example; the regional waste management of swine farms in the Lower Neuse River watershed in eastern North Carolina to achieve a 30% reduction in nitrogen loading. Results show that 1) a regional management approach is essential for achieving cost savings, 2) there is significant flexibility in meeting the nitrogen reduction and cost targets, 3) consideration of uncertainty may lead to the selection of a different solution, 4) the decision support framework can be used successfully to address a range of concerns, including but not limited to cost, risk, equity, and uncertainty.
2

NMR studies on the effects of model pollutants in selected invertebrate species

Gibb, Jason Ocean Telford January 1997 (has links)
No description available.
3

Information System for Environmental Technologies

Gomez Hernandez, Maria del Carmen 20 May 2005 (has links)
Geographical Information Systems (GIS) play an important role in environmental management solutions, and they are being used with increasing frequency in environmental studies. The use of GIS technology in environmental studies provides a better way to manage, analyze, display and share the information. In this thesis, I automated a process for constructing GIS maps of odor complaints and inspections that have been used to study odor complaints in the vicinity of three landfills in Jefferson Parish. I provided an application that integrates daily environmental observation and monitoring data into a GIS and publishes the resulting maps through the Internet. The user's interaction with the web-based maps does not require any GIS expertise. A Webapplication was also implemented for managing the list of the constructed maps. The maps are deleted or updated through the manager application, a friendly interface application that does not require users to have any GIS technology knowledge.
4

Development and Application of Hydraulic and Hydrogeologic Models to Better Inform Management Decisions

Stout, Trinity L. 01 August 2017 (has links)
Water is one of the most important and limited resources in regions with little rainfall. As populations continue to grow, so does the need for water. Individuals in water management positions need to be well informed in order to avoid potential negative effects concerning the overall quality and amount of water available for both people and the environment. In order to provide better information for these individuals, computer models and mathematical relationships are commonly developed to estimate the outcome of different situations regarding surface water and groundwater. Along these lines, this study focused on two modeling studies that provide information to managers regarding either stream restoration techniques or the amount of groundwater available. The first study investigated the effects that beaver dams have on streams. In order to do this, a computer model was developed to represent a section of stream with beaver dams and a section without. The model provided information regarding changes in the average depth, width, and velocity of the stream as a result of having beaver dams. We also measured changes in sediment size distributions between the two stream sections to confirm that beaver dams additionally impact sediment movement and channel shape. Results indicated that only a few dams are actually needed to achieve many of the desired changes in stream restoration. The second study involved testing an equation that was used to predict how much precipitation would become groundwater in a Midwestern watershed. Variables in the equation included measurements of natural or developed land, movement of water through soil, the depth of the water table, and hillslope steepness. We tested the equation in two western watersheds to determine if variables used in the earlier study remain relevant when applied under different conditions. The independent application of the method to each western watershed stressed the importance of meeting simplifying assumptions and developing more complete datasets. We also found that the application of existing simplified empirical relationships may not be suitable in estimating groundwater recharge in mountain watersheds.
5

Implementation of Land Use and Land Use Change and its Effects on Biodiversity in Life Cycle Assessment

Oyewole, Ayodeji January 2010 (has links)
Land use refers to the use of land for intensive human activities aiming at exclusive use of land for certain purposes and adapting the properties of land areas in view of these purposes. Environmental problems are, however, generated as a result of these human activities which modify the shape and properties of large land areas according to the requirements of human activities and thereby excluding wild animals and plants from coexisting on such land areas and in their neighbourhoods. Land use also leads to the degradation of the natural environment. Life Cycle Assessment (LCA) methodology is used for evaluating the environmental burdens associated with products or processes while taking their whole life cycle into consideration. LCA is a comprehensive assessment method which considers all aspects of natural environment, human health, and resources. Land use is regarded as an impact category in Life Cycle Assessment and is treated as such. However, the environmental impacts associated with land use and land use change are not being adequately considered in LCA, if considered at all.Life Cycle Impact Assessment is a part of LCA and is aimed at understanding and evaluating the magnitude and significance of the potential environmental impacts of products or processes and this involves developing characterization factors which link an environmental impact to a category indicator. In the assessment of land use impacts, characterization factors are developed so as to weigh the magnitude of environmental interventions such as land occupation and land transformation on the potentially affected attributes of ecosystem quality such as biodiversity, ecological functions and natural resources.The goal of this study is to review the progress of the implementation of land use and land use change as an impact category in LCA with a particular focus on biodiversity, recognize limitations, and indicate future prospects for the development of land use impact assessment methodologies and subsequent integration into LCA. Land use impacts are not being widely integrated into LCA because they are dependent on the regional or local situation which is not well known in LCA and land use as an environmental intervention is very complex. However, the importance of land use cannot be overemphasized when assessing products or processes which make use of raw materials that originate from land extensive activities. Despite this importance, there have been diverse arguments on how to include land use impacts, for example, on biodiversity in LCA so as to provide a common and acceptable methodology for this assessment.This study focuses on how land use impacts can be included in LCA. With a particular focus on land use impacts on biodiversity, the result of this review shows that only a few studies have been carried out. The problem of non-convergence of the methodology for the assessment of land use in LCA still persists because most of the proposed methodologies deal with different aspects of land use impacts and are therefore conflicting.Most of the studies reviewed stress the importance of biodiversity measured in terms of vascular plant species diversity. However, there are other methodologies which consider other impact pathways such as life support functions. The number of studies thereby correlates with an increase in the interest in the research area. However, it is difficult to identify any trend of convergence. Different methods are being proposed which do not actually agree with one another. Some of these methods are not “closely” related to the use of land in the normal usage sense. Most of the methods being proposed are exemplified in different regions and these have not been found to be applicable to global cases. This could be a limiting factor for the applicability of the proposed methodologies in LCA. In order to overcome these shortcomings, more research work would be needed before these methodologies could be incorporated into LCA which is presumed to be a global assessment methodology. This will enhance the credibility of the results provided by an LCA and the subsequent acceptability of the LCA methodology.
6

Environmental Impacts of Renewable Energy : An Overview of Life Cycle Results

Hung, Christine January 2010 (has links)
Selected non-renewable and renewable energy processes from the ecoinvent 2.2 life cycle inventory database were analysed using basic contribution analysis, geometric series expansion, and structural path analysis. The hierarchical perspective of the ReCiPe impact assessment method was applied. The sources studied included biomass, wind, solar photovoltaic, hydropower, natural gas combined cycle and hard coal. Several technologies within each energy source were studied for comparison purposes. The processes were compared based on material consumption, land use and emissions for the production of 1 EJ (278 TWh). Results indicate that all of the renewable energy sources studied had a significantly lower impact than the non-renewable sources chosen. With the exception of bioenergies and pumped reservoir hydropower, technologies for the same energy source showed similar behaviour in the analyses performed.The findings from this study confirm previous work stating the environmental and human health superiority of renewable energy technologies over fossil fuel energy.
7

Implementation of Land Use and Land Use Change and its Effects on Biodiversity in Life Cycle Assessment

Oyewole, Ayodeji January 2010 (has links)
Land use refers to the use of land for intensive human activities aiming at exclusive use of land for certain purposes and adapting the properties of land areas in view of these purposes. Environmental problems are, however, generated as a result of these human activities which modify the shape and properties of large land areas according to the requirements of human activities and thereby excluding wild animals and plants from coexisting on such land areas and in their neighbourhoods. Land use also leads to the degradation of the natural environment. Life Cycle Assessment (LCA) methodology is used for evaluating the environmental burdens associated with products or processes while taking their whole life cycle into consideration. LCA is a comprehensive assessment method which considers all aspects of natural environment, human health, and resources. Land use is regarded as an impact category in Life Cycle Assessment and is treated as such. However, the environmental impacts associated with land use and land use change are not being adequately considered in LCA, if considered at all.Life Cycle Impact Assessment is a part of LCA and is aimed at understanding and evaluating the magnitude and significance of the potential environmental impacts of products or processes and this involves developing characterization factors which link an environmental impact to a category indicator. In the assessment of land use impacts, characterization factors are developed so as to weigh the magnitude of environmental interventions such as land occupation and land transformation on the potentially affected attributes of ecosystem quality such as biodiversity, ecological functions and natural resources.The goal of this study is to review the progress of the implementation of land use and land use change as an impact category in LCA with a particular focus on biodiversity, recognize limitations, and indicate future prospects for the development of land use impact assessment methodologies and subsequent integration into LCA. Land use impacts are not being widely integrated into LCA because they are dependent on the regional or local situation which is not well known in LCA and land use as an environmental intervention is very complex. However, the importance of land use cannot be overemphasized when assessing products or processes which make use of raw materials that originate from land extensive activities. Despite this importance, there have been diverse arguments on how to include land use impacts, for example, on biodiversity in LCA so as to provide a common and acceptable methodology for this assessment.This study focuses on how land use impacts can be included in LCA. With a particular focus on land use impacts on biodiversity, the result of this review shows that only a few studies have been carried out. The problem of non-convergence of the methodology for the assessment of land use in LCA still persists because most of the proposed methodologies deal with different aspects of land use impacts and are therefore conflicting.Most of the studies reviewed stress the importance of biodiversity measured in terms of vascular plant species diversity. However, there are other methodologies which consider other impact pathways such as life support functions. The number of studies thereby correlates with an increase in the interest in the research area. However, it is difficult to identify any trend of convergence. Different methods are being proposed which do not actually agree with one another. Some of these methods are not “closely” related to the use of land in the normal usage sense. Most of the methods being proposed are exemplified in different regions and these have not been found to be applicable to global cases. This could be a limiting factor for the applicability of the proposed methodologies in LCA. In order to overcome these shortcomings, more research work would be needed before these methodologies could be incorporated into LCA which is presumed to be a global assessment methodology. This will enhance the credibility of the results provided by an LCA and the subsequent acceptability of the LCA methodology.
8

Environmental Impacts of Renewable Energy : An Overview of Life Cycle Results

Hung, Christine January 2010 (has links)
Selected non-renewable and renewable energy processes from the ecoinvent 2.2 life cycle inventory database were analysed using basic contribution analysis, geometric series expansion, and structural path analysis. The hierarchical perspective of the ReCiPe impact assessment method was applied. The sources studied included biomass, wind, solar photovoltaic, hydropower, natural gas combined cycle and hard coal. Several technologies within each energy source were studied for comparison purposes. The processes were compared based on material consumption, land use and emissions for the production of 1 EJ (278 TWh). Results indicate that all of the renewable energy sources studied had a significantly lower impact than the non-renewable sources chosen. With the exception of bioenergies and pumped reservoir hydropower, technologies for the same energy source showed similar behaviour in the analyses performed.The findings from this study confirm previous work stating the environmental and human health superiority of renewable energy technologies over fossil fuel energy.
9

Life Cycle Assessment of an Active House : Sustainability concepts by integrating energy, environment and well-being

Ghose, Agneta January 2012 (has links)
An emerging interest in constructing ultra low energy buildings, with low impact materials and maximizing the potential of using renewable energy reflects the potential in building industry to significantly contribute towards reducing environmental impacts. Life cycle assessments of the different green building prototypes provide a means to estimate the impacts of such buildings as well as provide suggestive improvements. The Active house in Stjørdal, Norway is one such prototype of a green building. This is a single family residence which is built with a concept of solar architecture in ultra low-energy buildings. It is challenging to harness solar energy at high latitudes. The Active house uses the fundamental construction details for a Passive house as mentioned in Norwegian regulatory standard, with specific changes in increasing the glazed surface to promote passive solar heat gain as well as increase daylighting , but also making it vulnerable to heat loss. The house is based on timber framework. Apart from electricity the house uses solar collectors which are connected to the hot water storage and hydronic floor heating. Space heating is also compensated by use of wood stoves. In the LCA results suggest that, based on the construction the Active house requires ten percent more energy than an equivalent Passive house which uses only electricity and wood. However, due to the effectivity of the solar collectors, it compensates for the need of the extra energy and in a lifetime of 60 years, it performs 15 % better , contributing to lesser environmental impacts than an equivalent Passive house. It is understood that extra embodied energy does not affect the environmental performance of a building if it results in better environmental performance (1). However, it is important to create demonstrable value of the building for the end user. Lifecycle assessment results from simulated operational use carries considerable error with respect to how the building actually performs. The results in this study have also been estimated with an approximate error factor derived from previous studies (2). There is a necessity to make every stakeholder of the building participative in the functioning of the building, inclusive of the end user, and maintaining the well-being. The case has also been scored in the basic categories of a sustainibility certification, with the results available from the lifecycle assessment and energy simulation.
10

Sustainable Dwellings and Intergenerational Equality - New Applications for Ecological Economics : A Systems Thinking Approach

Klar, David January 2011 (has links)
A systems thinking based approach was used to define and investigate the current state of knowledge in the academic disciplines related to sustainable residential dwellings via literature review. Semi-structured interviews were conducted with respondents connected to the system definition. The goal of the study was to determine the extent to which the academic disciplines, as well as the respondents, incorporated the social, economic, environmental and intergenerational aspects of sustainability. Significant variation was found in both the disciplines as well as in the responses of interviewees. Life-cycle cost analysis of dwellings built to the Norwegian passive house standard was used to investigate the implications of using alternative discount factors for extended assumed life spans. The results indicated that alternative discount factors have the potential to significantly reduce rental costs while fulfilling the potential Pareto optimality criterion. The alternative discount factors used in the life-cycle cost analysis were later shown to have flaws which limit their usefulness; a methodology for deriving a representative multigenerational discount rate was proposed.

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