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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.
11

Two Cost Analyses in Resource Economics: The Public Service Costs of Alternative Land Settlement Patterns and Effluent Allowance Trading in Long Island Sound

Speir, Cameron Lindsey 08 February 2000 (has links)
This study offers two cost analyses to inform public policy decisions on the use of land and water resources. The first presents some public service costs associated with different spatial forms of land development. The second cost analysis presents costs associated with three different policy options for meeting water quality goals in Long Island Sound. The objective the first analysis is to determine the cost to local governments of providing water distribution and wastewater collection services to alternative spatial forms of residential development. Components of spatial form are explicitly defined in terms of lot size, distance and tract dispersion. An engineering cost model is used to determine the water and sewer costs to three sets of hypothetical land settlement scenarios. Each set shows the effect of one component of spatial form on cost. The results show that smaller lots, shorter distances between existing centers and less tract dispersion reduce public water and sewer costs. Lot size is found to have the most pronounced effect on water and sewer cost. Some policy options for reducing the public service costs associated with development are considered. The objective of the second cost analysis is to analyze the cost implications of a nitrogen allowance trading system for wastewater treatment plants in Connecticut. Effluent allowance trading involves the transfer of pollution control responsibility between pollution sources. Effluent allowances are the right to discharge a given quantity of waste into the environment over a given time period. Allowance trading has been proposed as a way of reducing pollution control costs, encouraging innovative pollution prevention techniques and more quickly achieving water quality goals. Long Island Sound, a major estuary in the northeastern United States, experiences chronically low dissolved oxygen levels. Excessive nitrogen loads from anthropogenic activities in the Sound watershed have been identified as the cause of the oxygen problem. The state of Connecticut is examining the possibility of introducing an effluent allowance trading system in order to reduce the cost of achieving required reductions in nitrogen discharge. A linear programming model is used to predict trading outcomes and allowance prices. The total cost of achieving a nitrogen load cap is calculated under three administrative approaches. The first approach is a uniform reduction requirement where all plants are required to reduce discharge by the same proportion. The second approach is an administrative reallocation of waste load where a regulatory agency assigns control responsibility based on the agency's understanding of relative costs. The third approach is a flexible effluent allowance trading system. The results will show that a trading program offers cost savings over traditional regulatory approaches, demonstrate the potential for further cost savings from pollution prevention activities and estimate the cost savings that would result from including nonpoint sources in the overall nitrogen reduction strategy. / Master of Science
12

Essays on Water Policy and Coupled Human and Natural Systems

Weng, Weizhe 02 August 2019 (has links)
Human and freshwater ecosystems are intrinsically interconnected. To better design effective policies, modeling tools and valuation methods are necessary to help understanding the complex reciprocal linkages between ecosystem processes and human actions, and coupled human and natural systems (CNHS) sets up a critical paradigm to do so. It is thus of both academic and empirical appeal to integrate reliable economic valuation methods with tools and models from multiple disciplines in order to quantify the feedbacks between human and natural systems and to inform better policy design. Using freshwater resources as an example, this dissertation contains three essays which integrate natural science and economics models to understand how changes in human behavior and societal policies lead to changes in ecosystem services, and how changes in ecosystem services, in return, affect human decisions. The first two essays focus on agricultural nonpoint source pollution problems in United States and examines the impacts of potential water polices on both water polluters and water demanders. Specifically, in the first essay, a novel coupling between an ecological model of within-lake hydrodynamics and an economic model of hedonic property prices has been developed to quantify the connections between nutrient loading, lake water quality, and economic outcomes. Linking ecological processes with human decision-making provides a basis for enhanced evidence-based decision making in the context of reducing nonpoint-source pollution. In the second essay, an economic mathematical programming model is coupled with an agro-ecosystem model to investigate the behavioral adjustments and environmental pollution outcomes of water quality policies. A complete quantification of costs from all regulating sources are necessary to help pinpoint the efficient water policy design and reflecting the connection between human decisions and ecosystem processes. The third essay focus on the water quantity problem in another developed country, Australia. A discrete choice experiment method has been explored and used to provide estimates of willingness to pay for purchasing irrigation rights to restore a Ramsar-convention wetland. Water policy scenario described in this essay could directly affect the feedback between human and ecosystem processes and serve as a baseline for future planning and policy designs. By offering both conceptual and methodological advancements, this dissertation aims to improve the understanding of coupled human and natural systems and the implementation of water policies. This dissertation also provides a framework to establish multi-disciplinary dialogues and cooperation between scientists and economists in the search of efficient water polices. / Doctor of Philosophy / Freshwater resources are one of the most important elements in our daily life. It provides important goods and services to our society, but at the same time, due to human behaviors, freshwater resources are under threat in both their quality and quantity. This dissertation contains three essays which integrate knowledge from multiple disciplines to help understand and quantify the linkages between human and freshwater resources, and provides information to come up with better water polices. In the first essay, I explore the connections between nutrient loading, lake water quality, and the economic outcomes. The essay illustrates how potential change in nutrient loadings affect lake water quality, and how that induces people’s housing purchase behavior, property sales price and local governments’ property tax revenue. In the second essay, I focus on the agricultural production problem, which is one of the largest source for water quality degradation. By exploring the impacts of water policy on farmers’ production decisions, the essay sheds light on how to better design water polices to maintain farmers’ profit while simultaneously alleviating the impact of agricultural production to water qualities. In the third essay, I utilize a survey method, choice experiments, to elicit people’s willingness to pay for wetland ecosystem health. This could better allocate water resources between agricultural production use and residential use and come up with better water quantity polices.
13

Using an interdisciplinary approach to improve efficacy of agricultural conservation practices for protecting stream health

Mouser, Joshua Braden 19 August 2024 (has links)
Protecting water quality, biota, and ecosystem services of streams (cumulatively referred to as stream health) while increasing food production is a major global challenge. One way to balance these often-competing interests is through the installation of agricultural conservation practices, such as excluding livestock from streams via fencing and adjusting grazing patterns. However, conservation practices often do not improve stream health as expected. Failure to achieve stream health outcomes may be due to biophysical (e.g., conservation practices are not appropriate for the landscape) or social reasons (e.g., agricultural producers are not willing to use conservation practices). Therefore, the goal of my dissertation research was to understand factors influencing effectiveness of conservation practices using an interdisciplinary approach that integrates ecological engineering, ecology, and social science. My research focuses on southwest Virginia, a karst region where cattle grazing is common. In the introduction, I developed a social-ecological framework that outlines how the natural and social sciences can be used to guide effective placement and implementation of conservation practices and explain why interdisciplinary approaches are often necessary due to social-ecological connections that influence efficacy (i.e., feedbacks, heterogeneity, time lags, and thresholds). In Chapter 1, I modeled pollutant transport to characterize watershed features that contribute disproportionate amounts of pollutants to streams. I found that water, and associated nitrate, is primarily entering streams through subsurface pathways, whereas sediment is entering the stream through streambank erosion. Therefore, a combination of conservation practices that stop nitrogen at its source (e.g., nutrient management plans) and stabilize streambanks (e.g., fenced riparian buffers) could be useful for protecting stream health. For Chapter 2, I sampled water quality, habitat, and macroinvertebrates from 31 streams within sub-watersheds that span a range of pollutant yields, conservation practice densities, and agricultural land use extent to understand the pathways through which conservation practices influence stream health. Agricultural land use increased total nitrogen and decreased macroinvertebrate diversity, but conservation practices stabilized nitrogen and improved bank stability. Despite such improvements, adverse effects on water quality and habitat still limited the biotic assemblage. Therefore, innovative conservation practices, higher densities of existing practices, or allowing more time for the effects of existing practices to improve water quality and habitat may be required to achieve stream health goals. For Chapter 3, I surveyed producers to understand if they continue to use their conservation practices after their cost-share contracts end (i.e., persistence) and factors that influence persistence. Persistence was most strongly related to producers' attitudes towards the conservation practice, producers' motivations, and practice durability. Therefore, persistence could be encouraged by using producers' motivations to focus messaging on ways conservation practices are achieving producers' goals and allocating more funding to practice maintenance. Overall, my interdisciplinary approach led to a greater understanding of pollutant dynamics, the pathways through which conservation practices influence stream health, and social constraints to persistence. This knowledge can inform what conservation practices may be most effective and strategies to keep appropriate practices on the landscape long enough to achieve stream health goals. / Doctor of Philosophy / As farmers work to feed a growing worldwide population, streams can inadvertently receive pollution, like excess sediment and nitrogen. Too much sediment can clog the gills of aquatic animals and reduce their habitat, and too much nitrogen can cause excessive plant growth and decrease the amount of oxygen in the water. The cumulative effects of pollution from farming can result in streams being unable to support human uses such as clean drinking water and fishing opportunities. To increase food production while protecting streams, government agencies help farmers pay for the costs of using conservation practices that can reduce pollution. Examples of conservation practices include keeping livestock out of streams with fences, ensuring the ground is covered with plants in between planting crops, and developing a plan for the maximum amount of fertilizer that can be used. Unfortunately, conservation practices are sometimes ineffective, and streams still become polluted despite their use. My goal was to understand why some conservation practices are ineffective and how conservation practices might be improved for southwest Virginia. In the introduction, I developed a framework that illustrates how connecting the natural and social sciences can improve conservation practice efficacy by guiding planning and placement of new practices. In Chapter 1, I used a computer program to simulate pollution within streams so that I could understand which locations have the greatest amount of pollution and why. I found that nitrogen typically enters streams through the water in the soil rather than water running over the land surface and that sediment mostly enters the stream through erosion of the streambanks. These results suggest that conservation practices such as limiting the amount of nutrients placed on the landscape could be especially effective for reducing nitrogen pollution, whereas building fences to exclude cattle from streams and planting trees along streams can help reduce sediment pollution. For Chapter 2, I visited 31 streams in southwest Virginia that had varying amounts of pollution and conservation practices and collected water quality, habitat data, and aquatic insects. All these metrics are good indicators of pollution, but aquatic insects are particularly excellent indicators because their populations respond to cumulative changes in habitat and water quality. Streams with more conservation practices did not exhibit more diverse insect communities but did show stabilized water quality and habitat. These results indicate that the types of conservation practices currently used are not completely protecting streams and farmers may need to use more practices, new types of practices, or use their current practices for longer periods of time. For Chapter 3, I surveyed farmers to find out if they continue to use their conservation practices after funding from agencies ends, as well as their motivations for their actions. Farmers indicated that they were more likely to continue using conservation practices if their goals for using the practice were achieved and that they had difficulty keeping fences and trees from being destroyed by floods and wildlife. Government agencies could increase continued use of conservation practices by showing farmers how the practices are achieving their goals and by providing more funding to maintain practices. By combining research from several fields of study, I was able to better understand which conservation practices would be most effective in protecting streams and new ways to support farmers in using conservation practices.
14

Assessing environmental equivalents for water quality trading

Lee, Ming-Chieh January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / Water quality trading (WQT) is a market-based approach to improve water quality. It is an innovative, voluntary program that connects point source (PS) dischargers who need to reduce their pollutant loads with land managers who could offset those loads with nonpoint source (NPS) reductions to economically achieve water quality improvements in a watershed. The potential issues impeding WQT are its inability to address trading risks and quantify the uncertainty of potential load reduction in trades between PS and NPS. Recent research has also shown that trading information level and transaction costs cause problems in implementing WQT. Therefore, the goals of this study were to quantify the uncertainties of pollutant load reduction and delivery effect for potential trades, to estimate their spatiotemporal variations, and to provide information for stakeholders to reduce intangible costs of WQT. This study simulated agricultural cropland with more than 225 alternative land management practices to identify trends among these scenarios. Both total nitrogen and total phosphorus loads were modeled with SWAT and EUTROMOD for 36 years to analyze the potential load reduction, in-field uncertainty ratio, in-stream delivery ratio, and overall trading ratio (TR) in Lower Kansas watershed, Kansas. The analyses of site-specific effects in both geospatial and temporal aspects were also applied on subbasin level. The variant loading patterns and time distributions of each subbasin showed strong site-specific phenomena. The ANOVA of in-field nutrient load showed significant differences among the design criteria of scenarios. The results also showed a significant delivery and lake effects within the subbasins. The overall TR ranged from 1 to 2.2 or more in different scenarios. The advanced cluster analysis presented a potential method to eliminate the problems involved in fixed TRs while keeping the method simpler than finer-resolution floating TR system. Based on WQT geospatial data model, a three-tier GIS-based web interface Water Quality Trading Information Platform System (WQTIPS) was then developed for WQT information and assessment. A case study demonstrated WQTIPS can provide systematic, spatially information for stakeholders to assess the potential environmental benefit changes from the land management shifts using a simple interface. This study demonstrated that it is possible to automate water-quality trades, use watershed models to minimize trading risk and maximize water-quality benefits, and prioritize among possible trades both spatially and by BMP.
15

Application of Integrated Watershed Management Modeling on Non-point Source Pollution Evaluation for the Ai-Liao River Basin

Shen, Wei-Lin 23 August 2006 (has links)
In Taiwan, non-point source (NPS) pollution is one of the major causes of the impairment of surface waters. NPS pollutants, which are associated with stormwater runoff from agricultural land uses can be quite diffuse and difficult to treat. The I-Liao Creek Basin, located in southern Taiwan, flows through approximately 90-km and drains towards the Kaoping River. It is one of the major sub-basin in the Kaoping River watershed, which is the largest and the most intensively used watershed in Taiwan. Field investigation results indicate that the main water pollution sources in the I-Liao Creek Basin are domestic wastewater and NPS pollutants from agricultural activities. In this study, an Integrated Watershed Management Model (IWMM) was applied for simulating the water quality in the I-Liao Creek watershed. The model includes a global atmosphere module, a land module, a human impact module, a canopy module, and a global ocean module. Those modules can be linked and managed by a graphic user-interface. The model was calibrated and verified with field data, and was used to investigate potential NPS pollution management plans. Moreover, the Storm Water Management Model (SWMM) was used to verify the accuracy of the simulated results of flow and water qualities. Results from this study show that geographical information system (GIS) is an important mean for land-use identification and waste load estimation in the catchment. Linking the information of land utilization with the NPS pollution simulation model may further provide essential information of pollution potential of NPS pollution for all sub-regions in the river basin. Results and experience obtained from this study will be helpful in designing the watershed management and NPS pollution control strategies for other similar river basins.
16

Reduced Inputs Turfgrass Through White Clover Inclusion

Sparks, Bret Andrew 01 January 2014 (has links)
Most managed turfgrass species require frequent inputs to maintain an acceptable level of quality. Among these inputs, nitrogen (N) fertilization is usually the most limiting in terms of growth and development. However, N fertilization is also linked to non-point source (NPS) pollution. White clover (WC) is known for its ability to provide N when mixed into stands of turfgrass, and does not pose a threat for NPS pollution. Two field studies were designed to investigate the effects of WC inclusion in stands of cool-season turfgrasses. In the first field study, three cultivation techniques were examined for establishment of WC into preexisting turfgrass stands at three different seasonal timings. Scalping during the summer was seen as providing the highest WC populations, although scalping treatments also caused the most initial damage to the turfgrass. In the second field study, mixed stands of turfgrass and WC were examined for response to several weeks of traffic simulations, with WC withstanding the traffic events. Additionally, a greenhouse study was implemented to examine the effects of several commercial broadleaf herbicides on two WC varieties. Only 2,4-D was shown to be safe for application to both WC varieties, although Microclover did show tolerance to quinclorac applications.
17

Identifikace bodových zdrojů znečištění povrchových vod a jejich kvantifikace na vybraných povodích na Šumavě / Identification of point sources of surface water pollution and their quantification in selected catchments in the Šumava Mountains.

TOMKOVÁ, Zdeňka January 2010 (has links)
An evaluation of chemical parameters of surface waters proceed in the three small basin areas in Šumava Mountains, in the area of Svatý Tomáš highlands, during the year 2009: Bukový (woods), Mlýnský (semi{--}intensive and drained pasture, part of Pasečná village) and Horský stream (wetlands, woods, mowed meadows, a part of Svatý Tomáš village). The aim was to chart the three main periods during the year. The spring sampling (the 12th May) should illustrate the beginning of growing season with higher water flow rates. The summer sampling (the 21st July) is the period on the top of growing and touristic season, seasonal works in wood and especially in agriculture (grazing and mowing meadows). The last sampling (the 21st October) represents the season at the end of growing season, generally with the lowest flow rates in the stream, the end of touristic season and the end of full{--}area grazing. Already during the field research, involving the water sampling and conductivity measurement, there were some inflows with increased concentrations of dissolved solids found. Whereas in Bukový stream, as has been assumed, these inflows didn´t more or less occur, in Horský stream they had, relatively surprisingly but significantly, appeared immediately in headwater area. The elevated concentrations of dissolved solids occurred in Mlýnský stream in the whole area of basin, as has been assumed regarding to drainage and full{--}area grazing. One year monitoring proved the advantage of water quality evaluation using simple measurement of conductivity in field. High water conductivity in field was subsequently confirmed by laboratory analysis of selected ions. On the basis of identification of point sources of pollution, the recommendation improving present condition was suggested.
18

Modeling Occurrence and Assessing Public Perceptions of De Facto Wastewater Reuse across the USA

January 2014 (has links)
abstract: The National Research Council 2011 report lists quantifying the extent of de facto (or unplanned) potable reuse in the U.S. as the top research need associated with assessing the potential for expanding the nations water supply through reuse of municipal wastewater. Efforts to identify the significance and potential health impacts of de facto water reuse are impeded by out dated information regarding the contribution of municipal wastewater effluent to potable water supplies. This project aims to answer this research need. The overall goal of the this project is to quantify the extent of de facto reuse by developing a model that estimates the amount of wastewater effluent that is present within drinking water treatment plants; and to use the model in conjunction with a survey to help assess public perceptions. The four-step approach to accomplish this goal includes: (1) creating a GIS-based model coupled with Python programming; (2) validating the model with field studies by analyzing sucralose as a wastewater tracer; (3) estimating the percentage of wastewater in raw drinking water sources under varying streamflow conditions; (4) and assessing through a social survey the perceptions of the general public relating to acceptance and occurrence of de facto reuse. The resulting De Facto Reuse in our Nations Consumable Supply (DRINCS) Model, estimates that treated municipal wastewater is present at nearly 50% of drinking water treatment plant intake sites serving greater than 10,000 people (N=2,056). Contrary to the high frequency of occurrence, the magnitude of occurrence is relatively low with 50% of impacted intakes yielding less than 1% de facto reuse under average streamflow conditions. Model estimates increase under low flow conditions (modeled by Q95), in several cases treated wastewater makes up 100% of the water supply. De facto reuse occurs at levels that surpass what is publically perceived in the three cities of Atlanta, GA, Philadelphia, PA, and Phoenix, AZ. Respondents with knowledge of de facto reuse occurrence are 10 times more likely to have a high acceptance (greater than 75%) of treated wastewater at their home tap. / Dissertation/Thesis / Ph.D. Civil and Environmental Engineering 2014
19

Assessing the Effectiveness of the Roaring Branch BMP Retrofit Using Macroinvertebrate Bioassessment

Banning, James L 01 February 2010 (has links)
Using benthic macroinvertebrates to measure stream health has been widely used and accepted around the world. Macroinvertebrates are resident monitors of chronic impairment in a stream since they are relatively sessile and most commonly respond to disturbance by drift but can recolonize a restored stream reach very quickly. This study tested the effectiveness of macroinvertebrate metrics developed through the Rapid Bioassessment Protocol (RBP) to detect changes in stream integrity as the result of placement of a best management practice (BMP), installed on a tributary of Roaring Branch, located in Columbus, Georgia. The BMP was designed to attenuate flow to reduce sediment suspension and downstream deposition. A sampling protocol derived from the Georgia Ecoregions Project was implemented to evaluate the macroinvertebrate community, located downstream of the BMP, and downstream of the confluence with Roaring Branch, both before and after the BMP installation. The resulting metrics were compared to a reference condition described for subecoregion 65c, sandhills-lower piedmont. A dramatic improvement or increase of macroinvertebrate populations suggests an improvement in water quality (via reduction in fine sediment deposition) due to improved physical habitat conditions for indicators (Trichoptera) of healthier streams. The results of this study suggests further restoration activities should continue and that re-evaluation of the sampling protocol should take into account a larger subsample size of benthic macroinvertebrates than currently recommended by the RBP.
20

INVENTORY OF STORMWATER MANAGEMENT PRACTICES IN THE CITY OF OXFORD, OHIO

Kitheka, Bernard M., Mr. 25 May 2010 (has links)
No description available.

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