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

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

Date: May 2010
Creator: Enwright, Nicholas
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 nitrogen, phosphorus, heavy metals, and organic compounds. The use of LiDAR to characterize the hydrogeomorphic characteristics of wetlands is a key contribution of this study to the science of wetland functional assessment. LiDAR data was used to estimate volumes for the 7,370 wetlands and delineate catchments for over 4,000 wetlands, located outside the 100-yr floodplain, within a 2,075 square mile area around Galveston Bay. Results from this study suggest that coastal prairie freshwater wetlands typically have a moderate capacity to store surface water from precipitation events, remove ammonium, and retain phosphorus and heavy metals and tend to have a high capacity for removing nitrate and retainremove organic compounds. The results serve as a valuable survey instrument for increasing the understanding of coastal prairie freshwater wetlands ...
Contributing 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.

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

Access: Use of this item is restricted to the UNT Community.
Date: December 2005
Creator: McCall, Sarah
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 of water delivery systems in rural southern Trelawny's Cockpit Country; southern Trelawny residents' perceptions of the water situation; and policy and development goals in the context of Jamaica and southern Trelawny. I hope to bring attention to the unique social, geologic, and developmental context of water in Jamaica, and more specifically to garner attention for major water infrastructure improvements in south Trelawny. A number of recommendations for improvements with policy and infrastructure are made.
Contributing Partner: UNT Libraries
County Level Population Estimation Using Knowledge-Based Image Classification and Regression Models

County Level Population Estimation Using Knowledge-Based Image Classification and Regression Models

Date: August 2010
Creator: Nepali, Anjeev
Description: This paper presents methods and results of county-level population estimation using Landsat Thematic Mapper (TM) images of Denton County and Collin County in Texas. Landsat TM images acquired in March 2000 were classified into residential and non-residential classes using maximum likelihood classification and knowledge-based classification methods. Accuracy assessment results from the classified image produced using knowledge-based classification and traditional supervised classification (maximum likelihood classification) methods suggest that knowledge-based classification is more effective than traditional supervised classification methods. Furthermore, using randomly selected samples of census block groups, ordinary least squares (OLS) and geographically weighted regression (GWR) models were created for total population estimation. The overall accuracy of the models is over 96% at the county level. The results also suggest that underestimation normally occurs in block groups with high population density, whereas overestimation occurs in block groups with low population density.
Contributing Partner: UNT Libraries
Future Consumers Weigh in on Hybrid Vehicles: A Look at College Students' Opinions and KNowledge

Future Consumers Weigh in on Hybrid Vehicles: A Look at College Students' Opinions and KNowledge

Date: Spring 2007
Creator: Obregon, Nicole LeAnn
Description: Thesis written by a student in the UNT Honors College discussing hybrid vehicles, the development of such vehicles, and what college students know and believe about them.
Contributing Partner: UNT Honors College
Distribution and Probable Sources of Nitrate in the Seymour Aquifer, North Central Texas, USA

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

Access: Use of this item is restricted to the UNT Community.
Date: May 2001
Creator: Hillin, Clifford K.
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 in the central agricultural belt. Data indicated that this is an ongoing problem in the Seymour Aquifer and that agricultural activity and rural septic systems are the likely sources of the nitrate. Inconclusive results emphasized the need for a more comprehensive spatial and temporal water quality monitoring.
Contributing Partner: UNT Libraries
Bioreactor Landfill Cell Feasibility Study ' Reference to City of Denton Subtitle-D Permit #1590A Landfill

Bioreactor Landfill Cell Feasibility Study ' Reference to City of Denton Subtitle-D Permit #1590A Landfill

Date: May 2002
Creator: Roberts, Elizabeth
Description: The City of Denton Landfill, Permit #1590A, utilizes “Dry-Tomb” techniques for disposal and promotion of municipal solid waste stabilization, as described by the Resource Conservation and Recovery Act (RCRA) prohibition in 40 CFR. Bioreactor research suggests re-circulating leachate increases biodegradation rates and reduces long-term monitoring from fifty years to less than ten years. Current procedures that are followed at Denton's landfill, literature review and the use of the Hydrologic Evaluation of Landfill Performance (HELP) model, suggest that a bioreactor landfill cell is worthy of further research. Re-circulating leachate and augmenting it with additional liquid will increase biodegradation and the need to design and build a landfill gas collection system to capture methane for energy recovery uses.
Contributing Partner: UNT Libraries
Evaluation of a Common Carp (Cyprinus carpio L.) Exclusion and Trapping Device for Use in Aquatic Plant Founder Colony Establishment

Evaluation of a Common Carp (Cyprinus carpio L.) Exclusion and Trapping Device for Use in Aquatic Plant Founder Colony Establishment

Date: May 2008
Creator: Williams, Paul Edwin
Description: The focus of this study was to design and evaluate a trapping system that would reduce populations of common carp within water bodies in conjunction with establishment of native aquatic macrophytes founder colonies. A pond study and field study were conducted. A pond study was performed at the Lewisville Aquatic Ecosystem Research Facility, located in Lewisville, Texas, followed by a field study within a constructed wetland located in southern Dallas, Texas. For the pond study, twelve funnel traps were constructed (four reps of each type: control, dual-walled and ring cage). Two anti-escape devices were tested with funnels including steel fingers and hinged flaps. Ring cage and dual-walled treatments were planted using native pondweeds, while controls were left unplanted (additional bait and a drift fence scenarios were also tested). Common carp were introduced into the study pond. Chi-square statistical analyses were utilized and showed ring cage treatments using fingers as well as the use of a drift fence to be most effective. Following completion of the pond study, the two most effective treatments (controls and ring cages) were tested within the Dallas, Texas wetland; no carp were caught during the field test.
Contributing Partner: UNT Libraries
Comparison of Remediation Methods in Different Hydrogeologic Settings Using Bioplume II

Comparison of Remediation Methods in Different Hydrogeologic Settings Using Bioplume II

Date: May 1996
Creator: White, Sherry A. (Sherry Anne)
Description: A contaminant fate and transport computer model, Bioplume II, which allows simulation of bioremediation in ground water systems, was used to compare the effects of 11 remediation scenarios on a benzene plume. The plume was created in three different hydrogeologic settings from the simulation of an underground gasoline storage tank leak.
Contributing Partner: UNT Libraries
Green Improvements: A Consumer's Guide to Environmentally and Economically Responsible Home Repairs and Improvements for the North Central Texas Region

Green Improvements: A Consumer's Guide to Environmentally and Economically Responsible Home Repairs and Improvements for the North Central Texas Region

Date: August 2004
Creator: Dickason, Deborah
Description: The Consumer's Guide is designed to help consumers by providing guidelines for the purchase of specific energy-efficient household appliances- water heaters, air conditioning and heating systems, windows, dishwashers, refrigerators, clothes washers, and dryers. This serves two major purposes: to decrease the environmental impact of those products and to save consumers money over the lifetime of the products. The seven major appliances covered in this work are things that consumers tend to purchase quickly when their older models wear out and with little research into their energy and/or water efficiency. The guide begins with a general introduction and an explanation of the need for energy conservation. Explanations of how they work, purchasing tips, installation tips, maintenance tips, tips for additional energy efficiency, and case studies are given for each appliance. Printable pamphlets are included at the end.
Contributing Partner: UNT Libraries
Surface Water and Groundwater Hydrology of Borrow-Pit Wetlands and Surrounding Areas of the Lewisville Lake Environmental Learning Area, Lewisville, Texas

Surface Water and Groundwater Hydrology of Borrow-Pit Wetlands and Surrounding Areas of the Lewisville Lake Environmental Learning Area, Lewisville, Texas

Date: August 2004
Creator: Dodd-Williams, Lynde L.
Description: The focus of this study was to characterize the surface water and groundwater hydrology of borrow-pit wetlands located within the borders of the Lewisville Lake Environmental Learning Area (LLELA), east of the Elm Fork of the Trinity River. The wetlands were excavated into alluvial deposits downstream of the Lewisville Lake Dam. Both surface water and groundwater contribute to the hydro-period of the borrow-pit wetlands. Nearby marshes exhibit characteristics of groundwater discharge. Salinity in groundwater-fed wetlands could affect establishment of vegetation, as suggested from plant surveys. Surface water input from storm events dilutes salinity levels. Management of LLELA wetlands should include long-term evaluation of hydrology and plantings to enhance habitat. Plans for additional wetlands should consider both surface water and groundwater inputs.
Contributing Partner: UNT Libraries
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