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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

Effectiveness of Porous Pavement and an Infiltration Trench as Urban Best Management Practices

Lathrop, Mitchell Currie 11 February 1999 (has links)
The following study is a demonstration of the effectiveness of porous pavement and an infiltration trench as Best Management Practices (BMPs) in the reduction of stormwater and its constituents. The field work of the study was conducted from 1986 through 1988 and the report was written in 1990 and finalized in 1996. Results of the study show that porous pavement and the infiltration trench significantly reduced the volume of stormwater runoff as well as its constituents from an urban parking lot area. In addition, wetfall and dryfall were found to be the major contributors to the runoff loading and yet were not comparable to associated studies. Peak and total flow runoff volumes were reduced significantly thereby reducing the overall pollutant loading. Antecedent dry period was found to be related to pollutant loading but only up to about 5 days total. / Master of Science
2

EXPLORING THE UTILIZATION OF SUSTAINABLE DEVELOPMENT STRATEGIES FOR THE NEW PARKS IN THE MUNICIPALITIES OF THE GREATER TORONTO AREA

Nikzad, Amir Ardeshir 22 September 2011 (has links)
Sustainable urban parks provide social and economical benefits to the residents and contribute to the urban ecosystem health. Municipalities are responsible for development and management of urban parks and the goal of this study was to better understand if, and why, the municipalities in the Greater Toronto Area (GTA) have utilized sustainable development strategies in the planning, design, construction and management for their new park projects. A qualitative study utilizing an in-depth interview format was created based on the principles of sustainable development compiled from the Sustainable Sites Initiative. A sample of four municipalities in the GTA was selected based on population and development growth and the park authorities were contacted. The results indicated few sustainable initiatives implemented in the design and management stages of park development. Understanding the constraints against these suggest that there may be potential to increase the sustainability of urban parks. / The Goal of this thesis was to explore if, and why, the municipalities in the Greater Toronto Area (GTA) have or have not adopted sustainable development strategies in planning, design, construction and management of their new parks.
3

Calibration and verification of HSPF model for Tualatin River Basin water quality /

Tang, Fei. January 1993 (has links)
Thesis (M.S.)--Portland State University, 1993. / Computer-produced typeface. "Technical report EWR-003-93."--Cover. Includes bibliographical references (leaves 75-76). Also available on the World Wide Web.
4

Identifying Adopters of Best Management Practices within Mississippi Beef Producers and the Reasons for Non-Adoption

Cagle, M Scott 17 May 2014 (has links)
The goal of the Mississippi State University Extension Service (MSU-ES) is to improve the quality of life for all Mississippians. One specific group that agricultural change agents work with at the county level is beef producers. Grazing lands have received much attention over the last few years regarding environmental concerns and Best Management Practices (BMPs) for beef cattle operations. The adoption of these practices was voluntary during the time this study was conducted, however; adoption was highly encouraged by the MSU-ES and the Natural Resources Conservation Service (NRCS). By knowing the level of adoption of BMPs that Mississippi beef producers have implemented, change agents can more effectively plan educational programming efforts for producers to better understand the importance of BMP adoption. The purpose of this study was to describe the adopter categories of Mississippi beef producers as determined by Rogers (2003) adopter characteristics generalizations based on their (1) socioeconomic status, (2) personality values and communication behavior, and (3) opinions. It also examined the correlations between the adopter categories to predict the level of the three BMPs being studied. The adopter categories were innovator, early adopter, early majority, late majority, and laggard. The three BMPs that were the focus of the study were rotation grazing, riparian buffers, and pasture renovation. The results of the study indicated that Mississippi beef producers could be correctly identified in the adopter categories. By identifying the adopter categories of the Mississippi beef producers and then examining the correlations among the variables, prediction of BMP adoption of rotational grazing and riparian buffers was possible. The relationships between MSU-ES agents and their programming efforts, as well as the relationships between NRCS district conservationist and their programs, were studied. Nonoption, though not an adopter category, was also examined and the reasons for it were cited.
5

Optimization of BMP Selection for Distributed Stormwater Treatment Networks

Hodges, Clayton Christopher 19 July 2016 (has links)
Current site scale stormwater management designs typically include multiple distributed stormwater best management practices (BMPs), necessary to meet regulatory objectives for nutrient removal and groundwater recharge. Selection of the appropriate BMPs for a particular site requires consideration of contributing drainage area characteristics, such as soil type, area, and land cover. Other physical constraints such as karst topography, areas of highly concentrated pollutant runoff, etc. as well as economics, such as installation and operation and maintenance cost must be considered. Due to these multiple competing selection criteria and regulatory requirements, selection of optimal configurations of BMPs by manual iteration using conventional design tools is not tenable, and the resulting sub-optimal solutions are often biased. This dissertation addresses the need for an objective BMP selection optimization tool through definition of an objective function, selection of an optimization algorithm based on defined selection criteria, development of cost functions related to installation cost and operation and maintenance cost, and ultimately creation and evaluation of a new software tool that enables multi-objective user weighted selection of optimal BMP configurations. A software tool is developed using the nutrient and pollutant removal logic found in the Virginia Runoff Reduction Method (VRRM) spreadsheets. The resulting tool is tested by a group of stormwater professionals from the Commonwealth of Virginia for two case studies. Responses from case study participants indicate that use of the tool has a significant impact on the current engineering design process for selection of stormwater BMPs. They further indicate that resulting selection of stormwater BMPs through use of the optimization tool is more objective than conventional methods of design, and allows designers to spend more time evaluating solutions, rather than attempting to meet regulatory objectives. / Ph. D.
6

Farmer Adoption of Best Management Practices Using Incentivized Conservation Programs

Miller, Jennifer Christine 01 January 2014 (has links)
Many farms in the United States impose negative externalities on society. Population growth and the accompanying increase in demand for food further promote this trend of environmental degradation as a by-product of food production. The USDA's Environmental Quality Incentives Program (EQIP) provides financial assistance to farmers who wish to address natural resource concerns by making structural improvements or implementing best management practices (BMPs) on their farms. Regional examinations of program implementation and incentive levels are needed to evaluate the effectiveness of EQIP at both the farm and environmental level. This research addresses this need in the following two ways. First, conjoint analysis was used to calculate the willingness to accept incentive levels desired by Vermont farmers for implementing three common BMPs and the relative importance of each attribute in their adoption decisions. Next, a survey was conducted to document Vermont farmers' experiences, or choices not to engage, with EQIP. The results of the conjoint analysis indicated that farmers' adoption decisions are most heavily influenced by the available implementation incentives and that the higher the incentive level offered, the more willing farmers are to adopt a practice. The survey results triangulated these findings as cost was the most frequently cited challenge farmers face when implementing BMPs and one third of respondents felt the cost-share amount they had received was inadequate. Although 46% of respondents reported receiving nonmonetary benefits, 43% had encountered challenges when enrolling or participating in EQIP. In addition, though contracts are designed to address specific resource concerns, 30% of respondents had not fully fixed the original issues with their contracts. This also indicates that the incentive levels offered in EQIP contracts may be lower than Vermont farmers' preferred incentive levels, affecting the adoption rate of BMPs and subsequently the environmental health and long term sustainability of Vermont's agricultural systems. Program areas ripe for improvement, key points for farmers weighing the costs and benefits of program participation, and future research opportunities are discussed in order to guide efforts to improve the effectiveness of EQIP in Vermont. This research also raises awareness of how much it costs to simultaneously support environmental health and food production in our current food system and who ultimately should bear this financial burden.
7

Field-Scale Evaluation of Enhanced Agricultural Management Practices Using a Novel Unsaturated Zone Nitrate Mass Load Approach

Bekeris, Loren January 2007 (has links)
The monitoring of nitrate mass load through the unsaturated zone below agricultural land was proposed as a novel technique to assess the effect of agricultural best management practices (BMPs). The objectives of the study were to: develop field techniques and apply computational models for the quantification of unsaturated zone nitrate mass flux; scale the point mass flux results to a nitrate mass load across an agricultural parcel; and assess the resulting nitrate mass load measurements as indicators to evaluate the effect of a BMP. At several locations across the study site, groundwater quality and profiles of soil water content and temperature were regularly monitored, and several rounds of geologic cores were collected for analysis of bulk soil nitrate and an applied bromide tracer. The field data were applied in several analytical techniques for estimating recharge, and in two unsaturated zone numerical models used to refine the recharge estimates. The recharge rate at each measurement location was then combined with unsaturated zone nitrate data to quantify nitrate mass flux. Upscaling of the flux values to field-scale mass load was based mainly on topography, geology and field observations. The calculation of stored nitrate mass in the shallow subsurface showed some correlation to changes in surface nitrogen application, with the greatest decreases in stored mass observed at locations underlain by sand where there was a switch to a grass crop. In contrast, the calculation of nitrate mass load suggested that the post-BMP value (4.1 t NO3-N/yr) was greater than the pre-BMP value (2.2 t NO3-N/yr). However, the calculation of nitrate mass load was limited by several factors, including a lack of nitrate concentration data from the deep unsaturated zone and an above-average annual precipitation rate; as a result, the findings suggesting an increase in nitrate mass load in response to decreasing nutrient inputs should be interpreted with caution. Continued monitoring of nitrate mass load and stored nitrate mass in the unsaturated zone is recommended to determine whether further benefits from the BMPs are observed as the measurement period lengthens and the unsaturated zone is progressively flushed.
8

Field-Scale Evaluation of Enhanced Agricultural Management Practices Using a Novel Unsaturated Zone Nitrate Mass Load Approach

Bekeris, Loren January 2007 (has links)
The monitoring of nitrate mass load through the unsaturated zone below agricultural land was proposed as a novel technique to assess the effect of agricultural best management practices (BMPs). The objectives of the study were to: develop field techniques and apply computational models for the quantification of unsaturated zone nitrate mass flux; scale the point mass flux results to a nitrate mass load across an agricultural parcel; and assess the resulting nitrate mass load measurements as indicators to evaluate the effect of a BMP. At several locations across the study site, groundwater quality and profiles of soil water content and temperature were regularly monitored, and several rounds of geologic cores were collected for analysis of bulk soil nitrate and an applied bromide tracer. The field data were applied in several analytical techniques for estimating recharge, and in two unsaturated zone numerical models used to refine the recharge estimates. The recharge rate at each measurement location was then combined with unsaturated zone nitrate data to quantify nitrate mass flux. Upscaling of the flux values to field-scale mass load was based mainly on topography, geology and field observations. The calculation of stored nitrate mass in the shallow subsurface showed some correlation to changes in surface nitrogen application, with the greatest decreases in stored mass observed at locations underlain by sand where there was a switch to a grass crop. In contrast, the calculation of nitrate mass load suggested that the post-BMP value (4.1 t NO3-N/yr) was greater than the pre-BMP value (2.2 t NO3-N/yr). However, the calculation of nitrate mass load was limited by several factors, including a lack of nitrate concentration data from the deep unsaturated zone and an above-average annual precipitation rate; as a result, the findings suggesting an increase in nitrate mass load in response to decreasing nutrient inputs should be interpreted with caution. Continued monitoring of nitrate mass load and stored nitrate mass in the unsaturated zone is recommended to determine whether further benefits from the BMPs are observed as the measurement period lengthens and the unsaturated zone is progressively flushed.
9

AGRICULTURAL BEST MANAGEMENT PRACTICES AND THEIR EFFECTS ON SEDIMENT TRANSPORT CURVES FOR IMPROVED WATERSHED HEALTH

Stang, Conrad 23 January 2012 (has links)
Eutrophic conditions caused Severn Sound to be listed as an Area of Concern in the 1980’s, it was then delisted in 2002 after implementing a number of agricultural Best Management Practices (BMPs). The focus of this research is to evaluate BMP effectiveness on a watershed scale using both monitoring and modelling. The monitoring data clearly shows that the BMPs significantly reduced the sediment loadings. It also showed that BMPs affect only the intercept and not the slope of the sediment rating curves meaning that BMPs reduce sediment loadings in a linear fashion and at a constant percentage for all sizes of storms. The literature review and associated BMP reduction factors used to model the applied BMPs clearly show that observed and predicted reductions in sediment were experienced and that the model is validated for use on a watershed scale for BMP implementation. The results from this research will further the understanding of how sediment transport curves are affected by Best Management Practices. / Chapter 1 defines the problem and scope of the research study to be examined in this thesis. The literature review presents the current state of knowledge related to the effectiveness of BMPs, sampling techniques, and the use of sediment transport curves, and watershed modelling as a tool to evaluate the use of BMPs. Chapter 3 explains the goals and objectives as well as the study area for this research. Outlined in Chapter 4 are the standard methods used for water quality monitoring and setting-up and calibrating a watershed model. Research results are presented in Chapter 5 and include measured streamflow and water quality results for the respective rivers along with results from watershed modelling. The results section also reflects on the implications for BMP effectiveness and areas of future research. Chapter 6 concludes with a summary of the new information gained from this research and the success of Severn Sound in leading the way in improved use of BMPs for a healthier watershed. / Severn Sound Environmental Association, Greenland International Consulting Ltd., University of Guelph School of Engineering
10

Economic Policy and Resource Implications of Biofuel Feedstock Production

Adusumilli, Naveen 2012 August 1900 (has links)
Dramatically higher fuel prices and massive petroleum imports from politically unstable countries have contributed to a major national initiative to generate renewable fuels in the United States. Often, such policies are enacted and implemented with huge taxpayer expenditures without due diligence to the consequences. The evaluation of the water quality impacts of converting pastureland to intensive biomass production for fuel in a southern Texas watershed suggest significant increases erosion and nutrient loadings to water bodies. The Best Management Practices (BMPs), cover crop and filter strips when implemented individually failed to produce status-quo reduction levels. Combined BMPs implementation produced improved mitigation, at substantially higher costs, highlighting the issue of sustainability related to the economics of renewable fuels. The estimation of the net energy of biomass ethanol accounting for the production input data indicate a greater than one energy return for biomass crops. However, the policy results indicate that only 70 percent in net contribution to the energy supply is achieved due to relatively lower energy returns compared to conventional fossil fuels. In addition, because the ethanol produced has to have the energy used deleted from the total, the cost of producing a gallon of biomass ethanol is substantially higher than that of gasoline. The impacts of an exogenously-specified biofuel mandate fulfilled by the production of a dedicated biomass crop and its consequent effects on commodity prices and overall welfare are estimated. Net farm income increased due to an increase in crop prices; however, both consumer surplus and total surplus decreased. The analysis is extended to estimate the sensitivity of Conservation Reserve Program (CRP) acres returning to crop production and the potential of higher biomass yields. The results indicate that net farm income decreased and consumer surplus increased due to a decrease in crop prices, resulting in an increase in overall welfare. This current research evaluates the unintended consequences of the U.S. energy policy and provides interesting insights of the potential economic and environmental impacts. These results suggest policy makers should be cautious before enacting energy policy and consider multiple alternative energy sources in an economic and financial context to achieve a sustainable energy goal.

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