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Assessment of Transportation Emissions for Ferrous Scrap Exports from the United States: Activity-Based Maritime Emissions Model and Theoretical Inland Transportation Model.

Description: Industrial ecology is a field of study that encourages the use of closed-loop material cycles to achieve sustainability. Loop closing requires the movement of materials over space, and has long been practiced in the iron and steel industry. Iron and steel (ferrous) scrap generated in the U.S. is increasingly exported to countries in Asia, lengthening the transportation distance associated with closing the loop on the iron and steel life cycle. In order to understand the environmental cost of… more
Date: December 2011
Creator: Caldwell, Amanda
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Urban Trees as Sinks for Soot: Deposition of Atmospheric Elemental Carbon to Oak Canopies and Litterfall Flux to Soil

Description: Elemental carbon (EC), a product of incomplete combustion of fossil fuels and biomass, contributes to climate warming and poor air quality. In urban areas, diesel fuel trucks are the main source of EC emissions from mobile sources. After emission, EC is deposited to receptor surfaces via two main pathways: precipitation (wet deposition) and directly as particles (dry deposition). Urban trees may play an important role in removing EC from the atmosphere by intercepting and delivering it directly… more
Date: May 2018
Creator: Rindy, Jenna
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Identifying Cultural and Non-cultural Factors Affecting Litter Patterns in Hickory Creek, Texas

Description: Plastic deposition in hydrological systems is a pervasive problem at all geographic scales from loci of pollution to global ocean circulation. Much attention has been devoted to plastic deposition in marine contexts, but little is known about inputs of plastics into local hydrological systems, such as streams. Any attempt to prevent plastic litter must confront people’s behaviors, so archaeological concepts are used to distinguish between various cultural inputs (e.g., littering) and non-cultur… more
Date: August 2014
Creator: Carpenter, Evan S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Use of GIS to Identify and Delineate Areas of Fluoride, Sulfate, Chloride, and Nitrate Levels in the Woodbine Aquifer, North Central Texas, in the 1950s, 1960s, 1970s, 1980s, and 1990s

Description: ArcView and ArcInfo were used to identify and delineate areas contaminated by fluoride, sulfate, chloride, and nitrate in the Woodbine Aquifer. Water analysis data were obtained from the TWDB from the 1950s to 1990s covering 9 counties. 1990s land use data were obtained to determine the relationship with each contaminant. Spearman's rank correlation coefficients and Kruskal-Wallis tests were used to calculate relationships between variables. Land uses had little effect on distributions of conta… more
Date: August 2001
Creator: Sanmanee, Sirichai
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Distribution and Probable Sources of Nitrate in the Seymour Aquifer, North Central Texas, USA

Description: This study utilized GIS and statistical methods to map the spatial variability of nitrate and related groundwater constituents in 30 counties above the Seymour Aquifer, analyze temporal patterns of nitrate pollution, identify probable sources of pollution, and recommend water development strategies to minimize exposure to nitrate and reduce future aquifer contamination. Nitrate concentrations in excess of 44 mg/L (US EPA limit) were commonly observed in the Seymour Aquifer region, especially i… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2001
Creator: Hillin, Clifford K.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

The Landscape Legacies of Gas Drilling in North Texas

Description: In North Texas, the Barnett Shale underlies large areas of the Dallas-Fort Worth Metroplex (DFW), which magnifies debates about the externalities of shale gas development (SGD). Continued demand for natural gas and expansive urbanization in DFW will cause more people to come in contact with drilling rigs, gas transport, and other urban shale gas landscapes. Thousands of gas wells within the DFW region occupy a large, yet scattered land surface area. DFW city planners, elected officials, and oth… more
Date: May 2016
Creator: Sakinejad, Michael Cyrus
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Exceedance Frequency Analysis of Urban Stormwater Quality and Its Relation to Land Use Change, Denton, Texas

Description: Urbanization causes various environmental issues including water pollution, air pollution, and solid waste. Urbanization of watersheds has a profound influence on the quality of stormwater runoff. The quality of stormwater runoff is highly associated with land use. This study analyzed the exceedance frequency of stormwater quality in five watersheds of Denton over eleven years and also analyzed the relationship between stormwater quality and land use/cover of each watershed. The results showed … more
Date: August 2015
Creator: Shrestha, Manjul
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Soil Carbon Accumulation in an Urban Ecosystem: Canopy Cover and Management Effects

Description: Black carbon (BC), a stable form of organic carbon (OC), is a byproduct of the incomplete combustion of biomass, biofuels, and fossil fuel. The main objectives of this research are to examine the spatial distribution of OC and BC in urban soil and determine the influence of tree canopy cover and landscape maintenance on soil carbon accumulation. Soil sampling was conducted at 29 sites throughout the City of Denton, Texas, in May 2019. Samples were collected from underneath post oak canopies and… more
Date: May 2020
Creator: Kang, Katherina A
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Retail Change and Light Rail: an Exploration of Business Location Changes Accompanying Commuter Rail Development in Denton County, Texas

Description: Within the past few decades, commuter rail routes in several major metropolitan areas have been implemented to provide an alternative to automobile transportation. Urban planners in these cities are looking to commuter rail to mitigate congestion and pollution. However, research on the impacts of commuter rail development on the surrounding retail landscape is still needed. In metropolitan Dallas-Fort Worth, the Denton County Transportation Authority recently opened its new A-Train light rail s… more
Date: August 2014
Creator: Yarbrough, Trevor S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Integrating GIS with Benthic Metrics: Calibrating a Biotic Index to Effectively Discriminate Stream Impacts in Urban Areas of the Blackland Prairie Eco-Region

Description: Rapid Bioassessment Protocols integrate a suite of community, population, and functional metrics, determined from the collection of benthic macroinvertebrates or fish, into a single assessment. This study was conducted in Dallas County Texas, an area located in the blackland prairie eco-region that is semi-arid and densely populated. The objectives of this research were to identify reference streams and propose a set of metrics that are best able to discriminate between differences in community… more
Date: December 2003
Creator: Earnest, Steven F. P.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

An Exploration of the Ground Water Quality of the Trinity Aquifer Using Multivariate Statistical Techniques

Description: The ground water quality of the Trinity Aquifer for wells sampled between 2000 and 2009 was examined using multivariate and spatial statistical techniques. A Kruskal-Wallis test revealed that all of the water quality parameters with the exception of nitrate vary with land use. A Spearman’s rho analysis illustrates that every water quality parameter with the exception of silica correlated with well depth. Factor analysis identified four factors contributable to hydrochemical processes, electr… more
Date: August 2011
Creator: Holland, Jennifer M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Are Streams Protected? Outcomes of Environmental Regulation

Description: Urban areas experience the loss of natural stream channels through conversion to artificial conveyances. This process tends to target headwater and other low order streams. The purpose of this study is to determine the patterns of stream loss in Denton, Texas, and explore the regulatory structure that manages these streams. Historic and current maps and stream data are used to map Denton's streams and categorize them according to their vertical connectivity as: 1) "intact", streams that are … more
Date: August 2017
Creator: Rowen, Zachary
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Using Geographic Information Systems for the Functional Assessment of Texas Coastal Prairie Freshwater Wetlands Around Galveston Bay

Description: The objective of this study was to deploy a conceptual framework developed by M. Forbes using a geographic information system (GIS) approach to assess the functionality of wetlands in the Galveston Bay Area of Texas. This study utilized geospatial datasets which included National Wetland Inventory maps (NWI), LiDAR data, National Agriculture Imagery Program (NAIP) imagery and USGS National Land Cover data to assess the capacity of wetlands to store surface water and remove pollutants, including… more
Date: May 2010
Creator: Enwright, Nicholas
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas

Description: Rainfall interception is one mechanism by which tree canopies can reduce surface runoff in urban areas. The objectives of this research were to: 1) quantify rainfall interception by urban tree canopies, and 2) determine the influence of vegetation and microenvironmental factors on rainfall interception rates. In the city of Denton, Texas, 30 mature post oak (Quercus stellata) and blackjack oak (Quercus marilandica) trees were selected for study. Trees were assigned to one of three categories… more
Date: May 2017
Creator: Edington, Patrick
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

An Assessment of Riparian Buffer Effectiveness in the Upper Hickory Creek Watershed: A GIS Approach Using the Riparian Buffer Delineation Equation (RBDE) and the Buffer Improvement Potential Percentage (BP)

Description: As population increases and urbanization occurs, watershed management will be critical in the protection of water resources in North Central Texas. By 2040, Denton County will nearly double its 2010 population. The Upper Hickory Creek Watershed lies west of Denton and empties into Lake Lewisville. Lake Lewisville provides drinking water for Denton, Dallas, and other neighboring cities. Mitigation of non-point source pollutants as a result of urban and agricultural practices is essential to prot… more
Date: May 2019
Creator: Yesildirek, Monica Veale
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Spatio-temporal Variation of Nitrate Levels in Groundwater in Texas, 1970 to 2010

Description: This study looks at spatial variation of groundwater nitrate in Texas and its fluctuations at 10 year increments using data from the Texas Water Development Board. While groundwater nitrate increased in the Ogallala and Seymour aquifers across the time period, the overall rate in Texas appears to be declining as time progresses. However, the available data is limited. Findings show that a much more targeted, knowledge based strategy for sampling would not only reduce the cost of water qualit… more
Date: December 2012
Creator: Rice, Susan C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Effects of Vegetation Structure and Canopy Exposure on Small-scale Variation in Atmospheric Deposition Inputs to a Mixed Conifer Forest in California

Description: Data on rates of atmospheric deposition is limited in many montane ecosystems, where high spatial variability in meteorological, topographic, and vegetation factors contributes to elevated atmospheric inputs and to the creation of deposition hotspots. Addressing the ecological consequences of increasing deposition in these areas will require a better understanding of surface controls influencing atmospheric deposition rates at both large and small-scales. The overarching objective of this thesi… more
Date: May 2014
Creator: Griffith, Kereen
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Green Entrepreneurialism and the Making of the Trinity River Corridor: The Intersection of Nature and Capital in Dallas, Texas

Description: Since the adoption of neoliberalism, many cities have taken to integrating nature with capital accumulation to create a sense of place. This has been closely tied to urban greening, or green "revitalization." As part of curating this desired character, city governments are working to roll out plans to restore and renew neighborhoods using their natural landscapes through methods such as reforestation, the creation of parks, and commercial development. These cities, deemed Entrepreneurial cities… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: May 2019
Creator: Krupala, Katie Ilene
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Water systems, water policy, and Karst terrain: An analysis of the complex relationships between geology, economy, public perceptions, and policy in southern Trelawny, Jamaica.

Description: Jamaica has an abundance of freshwater resources, however, a lack of infrastructure makes treated, piped water inaccessible in many areas. Through literature reviews and site visits, this thesis is an analysis of how the people and land, and money and policy, interact with one another in relation to Jamaica's freshwater resources and water infrastructure. Special attention is given to the island's type-example Cockpit karst geology; tourism, mining, and farming's relation to this karst; types o… more
Access: Restricted to the UNT Community Members at a UNT Libraries Location.
Date: December 2005
Creator: McCall, Sarah
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Rail Transit and Its Influence on Land Use: A Dallas Case Study

Description: Mass transit investments continue to be utilized in many cities as means of dealing with various transportation issues. In Dallas Texas, light rail transit was developed with the hopes of encouraging compact and orderly growth. This research uses the DART system as a case study in examining transportation/land use relationships in Dallas. As such, this thesis reviews past research that examined transit systems impacts on urban areas, analyzes historical changes in land use pattern development a… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2001
Creator: Farrow, Melissa A.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Efficiency of Nitrate and Phosphorus Removal in a Working Rain Garden

Description: Rain gardens are low impact developments designed to mitigate a suite of issues associated with urban stormwater runoff. The site for this study was a Denton City rain garden at the Denton Waste Water Treatment Plant. Nitrogen and phosphorus removal was examined in light of two overflow events comprised of partially treated wastewater from an upslope anaerobic digester pond. Nitrate removal efficiency was examined across differing dry spell intervals of 5, 8, and 12 d, displaying a moderate neg… more
Date: August 2015
Creator: Strong, Patrick
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Measuring the value of transit access for Dallas County: A hedonic approach.

Description: Advocates of urban light rail transit argue that positive developments around station area(s) should offset the costs of implementing a transit system by creating more livable communities and enhance surrounding residential property values. In some cases, decreased urban landscape aesthetics have been reported. The purpose of this study is to contribute to this debate via an analysis of the impact of the Dallas Area Rapid Transit system on residential property values in Dallas County. By examin… more
Date: August 2007
Creator: Leonard, Christopher
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

A Storm Water Runoff Investigation Using Gis and Remote Sensing

Description: Environmental controls are becoming more and more expensive to implement, so environmental management is becoming more technologically advanced and efficient through the adoption of new techniques and models. This paper reviews the potential for storm water runoff for the city of Denton, Texas and with the main objective to perform storm water runoff analyses for three different land use datasets; each landuse dataset created with a different methodology. Also analyzed was the difference betwee… more
Date: August 2012
Creator: Jennings, Laura
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

National Patterns and Community Impacts of Major Domestic U.S. Military Base Closures, 1988-present

Description: This thesis analyses major U.S. military bases closed by the Base Realignment and Closure (BRAC) Commission since 1988. The study focuses on geographic patterns of pre-existing versus BRAC bases, statistical attributes, environmental restoration, and reuse of bases. Comparative case studies supplement the analysis, highlighting rural versus urban location, success versus failure, politics, conflict, and local versus national goals. Thesis findings are that: 92 bases closed versus 97 commonly pu… more
Date: August 2004
Creator: Webster, Sean T.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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