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open access

Assessing Outcomes of a Recycling Education and Service Program within an Elementary School

Description: During the spring 2004 a pilot school recycling program was implemented within Robert E. Lee Elementary. The primary goal of the program was to determine how recycling education in the school would affect curbside recycling rates within the surrounding community. The program was a cooperative effort between the University of North Texas, City of Denton Solid Waste Department and Keep Denton Beautiful. Throughout the first months of the study during the spring 2004, an increase in curbside rec… more
Date: August 2005
Creator: Cunningham-Scott, Carey Beth
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing Regional Gully Erosion Risk: A Remote Sensing and Geographic Information Systems Approach

Description: Gully erosion has been established as a major source of sediment pollution in the upper Trinity River watershed in north-central Texas. This fact, along with a lack of models appropriate for a large-area gully erosion analysis established a need for a gully erosion study in the upper Trinity basin. This thesis project attempted to address this need by deriving an index indicative of gully erosion risk using remote sensing and geographic information systems (GIS) methodology. In context of previ… more
Date: August 1995
Creator: Sill, Paul E. (Paul Eric)
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessing the Spatial and Temporal Distribution of MTBE and BTEX Compounds in Lake Lewisville, Texas February 1999 - February 2000

Description: The spatial and temporal distribution of Methyl Tertiary-Butyl Ether (MTBE) and BTEX (Benzene, Toluene, Ethylbenzene, Xylenes) compounds were assessed in a multipurpose reservoir, Lake Lewisville, Texas between February 1999 and February 2000. Concentrations of MTBE ranged from 0.0 - 16.7 mg/L. Levels of MTBE in the lake were related to watercraft. BTEX concentrations were never detected above 2.0 mg/L during the sampling period. Finished drinking water from Denton and the Upper Trinity Regio… more
Date: August 2000
Creator: Lee, Anne W.
Item Type: Refine your search to only Thesis or Dissertation
open access

Assessment of Radio-Tagged Grass Carp (Ctenopharnygodon idella) Dispersion, Vegetation, and Temperature Preferences in North Lake Reservoir

Description: Twenty-nine (Group One, June 8,1995) grass carp (Ctenopharyngodon idella) and five (Group Two, April 18, 1996) grass carp were radio-tagged to monitor movement patterns and habitat preferences on North Lake, a 335 hectare multi-use reservoir located in Irving, Texas. Overall fish mean Average Daily Movement (ADM) rates were 49.2 meters/day (during Half One, 6/8/95-11/30/95) and 5.3 meters/day (during Half Two, 12/14/95-6/6/96). Aquatic macrophtye distribution data were obtained. Radio-tagged gr… more
Date: August 1996
Creator: Lacewell, Jason (Jason Lawrence)
Item Type: Refine your search to only Thesis or Dissertation
open access

An Assessment of Storm Water Toxicity from the Dallas/Fort Worth Metroplex and Denton, Texas

Description: With the advent of national storm water regulations, municipalities with populations greater than 100,000 are required to obtain National Pollutant Discharge Elimination System Permits (NPDES) for storm water discharges. In addition to the sampling required for the permit process, the City of Fort Worth contracted with the University of North Texas' Institute of Applied Sciences to conduct acute toxicity testing using Pimephales prcmelas and Ceriodaphnia dubia on storm water samples received fr… more
Date: August 1995
Creator: Keating, Paul Redmond
Item Type: Refine your search to only Thesis or Dissertation
open access

Bioconcentration of Triclosan, Methyl-Triclosan, and Triclocarban in the Plants and Sediments of a Constructed Wetland

Description: Triclosan and triclocarban are antimicrobial compounds added to a variety of consumer products that are commonly detected in waste water effluent. The focus of this study was to determine whether the bioconcentration of these compounds in wetland plants and sediments exhibited species specific and site specific differences by collecting field samples from a constructed wetland in Denton, Texas. The study showed that species-specific differences in bioconcentration exist for triclosan and triclo… more
Date: August 2011
Creator: Zarate, Frederick M., Jr.
Item Type: Refine your search to only Thesis or Dissertation
open access

Biotic Factors and Temperature Tolerances via Critical Thermal Methodology in Goldfish

Description: CTMinimum and CTMaximum were measured in 620 goldfish to determine if biotic factors, in particular starvation, condition factor and size, affect temperature tolerance. Twenty-eight days of starvation adversely affected both upper and lower temperature tolerance. Condition factor was related to upper but not lower temperature tolerance.
Date: August 1999
Creator: Ford, Tiiu Kirsti, 1972-
Item Type: Refine your search to only Thesis or Dissertation

Characterizing the Municipal Solid Waste Stream in Denton, Texas

Description: Forty-two commercially collected dumpsters from Denton’s Municipal Solid Waste Stream were emptied, sorted and weighed to characterize the material types and make preliminary recycling policy recommendations. The general composition of Denton’s solid waste stream was not significantly different from the composition of the nation’s solid waste stream. Fifty-eight percent of the observed waste stream was recyclable. Paper made up the largest portion of recyclable materials and the "grocery" sourc… more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2000
Creator: Brady, Patricia D.
Item Type: Refine your search to only Thesis or Dissertation
open access

Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Description: Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were d… more
Date: August 2013
Creator: Woodard, Jennifer Kristin
Item Type: Refine your search to only Thesis or Dissertation

Comparison of GPS Point Selection Methods for GIS Area Measurement of Small Jurisdictional Wetlands

Description: U.S. Army Corps of Engineers (USACE) regulates fill of jurisdictional waters of the United States including wetlands. Recent USACE regulations set a threshold of impacts to wetlands at one-half acre. Impact area can be determined by Global Positioning System (GPS) measurement of wetland boundary and Geographic Information System (GIS) calculation of impact area. GPS point selection methods include (1) equal time interval, (2) transect and (3) intuition. Four two-acre shapes were measured with e… more
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Date: August 2001
Creator: Shelton, Michael
Item Type: Refine your search to only Thesis or Dissertation
open access

Concentrations of Triclosan in the City of Denton Wastewater Treatment Plant, Pecan Creek, and the Influent and Effluent of an Experimental Constructed Wetland

Description: The Pecan Creek Waste Reclamation Plant in Denton, Texas, an activated sludge WWTP, was sampled monthly for ten months to determine seasonal and site variation in concentrations of triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol), an antibacterial additive. SNK separation after the highly significant ANOVA on ranked data were: summer = fall > winter = spring and influent > downstream = effluent = wetland inflow > wetland outflow (a=0.05). After the plant converted to ultraviolet disinfection… more
Date: August 2004
Creator: Waltman, Elise Lyn
Item Type: Refine your search to only Thesis or Dissertation
open access

Ecological Responses to Severe Flooding in Coastal Ecosystems: Determining the Vegetation Response to Hurricane Harvey within a Texas Coast Salt Marsh

Description: Vegetative health was measured both before and after Hurricane Harvey using remotely sensed vegetation indices on the coastal marshland surrounding Galveston Island's West Bay. Data were recorded on a monthly basis following the hurricane from September of 2005 until September of 2019 in order to document the vegetation response to this significant disturbance event. Both initial impact and recovery were found to be dependent on a variety of factors, including elevation zone, spatial proximity … more
Date: August 2021
Creator: Hudman, Kenneth Russell
Item Type: Refine your search to only Thesis or Dissertation
open access

Effects of Macrophyte Functional Diversity on Taxonomic and Functional Diversity and Stability of Tropical Floodplain Fish Assemblages

Description: Multiple dimensions of biodiversity within and across producer and consumer guilds in the food web affect an ecosystem’s functionality and stability. Tropical and subtropical aquatic ecosystems, which are extremely diverse, have received much less attention than terrestrial ecosystems in regards to the effects of biodiversity on ecosystem functioning. We conducted a field experiment that tested for effects of macrophyte functional diversity on diversity and stability of associated fish assembl… more
Date: August 2015
Creator: Treviño, Jessica Marie
Item Type: Refine your search to only Thesis or Dissertation
open access

Estimated Extent and Fate of Chlorinated Solvent Contamination in the Soil of the Naval Air Station, Dallas, Texas

Description: This thesis estimates the spatial extent of chlorinated solvent contamination of the soil at the Naval Air Station, Dallas, then estimates the fate and transport of these contaminants, over time, using the Soil Transport and Fate database and the Vadose-Zone Interactive Processes (VIP) modeling software. Geostatistical analysis identifies two areas with serious chlorinated solvent contamination. Fate and transport modeling estimates that this contamination will degrade and disperse from the soi… more
Date: August 1998
Creator: Trescott, Jill V. (Jill Virginia)
Item Type: Refine your search to only Thesis or Dissertation
open access

Evaluating Tree Seedling Survival and Growth in a Bottomland Old-field Site: Implications for Ecological Restoration

Description: In order to assess the enhancement of seedling survival and growth during drought conditions, five-hundred bare-root seedlings each of Shumard oak (Quercus shumardii Buckl.) and green ash (Fraxinus pennsylvanica Marsh.) were planted each with four soil amendments at a Wildlife Management Area in Lewisville, Texas. The treatments were a mycorrhizal inoculant, mulch fabric, and two superabsorbent gels (TerraSorb® and DRiWATER®). Survival and growth measurements were assessed periodically for two … more
Date: August 2007
Creator: Boe, Brian Jeffrey
Item Type: Refine your search to only Thesis or Dissertation

An examination of the riparian bottomland forest in north central Texas through ecology, history, field study, and computer simulation

Description: This paper explores the characterization of a riparian bottomland forest in north central Texas in two ways: field study, and computer simulation with the model ZELIG. First, context is provided in Chapter One with a brief description of a southern bottomland forest, the ecological services it provides, and a history of bottomland forests in Texas from the nineteenth century to the present. A report on a characterization study of the Lake Ray Roberts Greenbelt forest comprises Chapter Two. The … more
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: August 2001
Creator: Holcomb, Sheralyn S.
Item Type: Refine your search to only Thesis or Dissertation
open access

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

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 purch… more
Date: August 2004
Creator: Dickason, Deborah
Item Type: Refine your search to only Thesis or Dissertation
open access

Hepatotoxicity of Mercury to Fish

Description: Tissue samples from spotted gar (Lepisosteus oculatus) and largemouth bass (Micropterus salmoides) were collected from Caddo Lake. Gar and bass livers were subjected to histological investigation and color analysis. Liver color (as abs at 400 nm) was significantly correlated with total mercury in the liver (r2 = 0.57, p = 0.02) and muscle (r2 = 0.58, p = 0.01) of gar. Evidence of liver damage as lipofuscin and discoloration was found in both species but only correlated with liver mercury con… more
Date: August 2010
Creator: Barst, Benjamin Daniel
Item Type: Refine your search to only Thesis or Dissertation
open access

The impact of invertebrates to four aquatic macrophytes: Potamogeton nodosus, P. illinoensis, Vallisneria americana and Nymphaea mexicana.

Description: This research investigated the impact of invertebrates to four species of native aquatic macrophytes: V. americana, P. nodosus, P. illinoensis, and N. mexicana. Two treatments were utilized on each plant species, an insecticide treatment to remove most invertebrates and a non-treated control. Ten herbivore taxa were collected during the duration of the study including; Synclita, Paraponyx, Donacia, Rhopalosiphum, and Hydrellia. Macrophyte biomass differences between treatments were not measu… more
Date: August 2008
Creator: Nachtrieb, Julie Graham
Item Type: Refine your search to only Thesis or Dissertation
open access

Laboratory and field studies of cadmium effects on Hyalella azteca in effluent dominated systems.

Description: Laboratory single-species toxicity tests are used to assess the effects of contaminants on aquatic biota. Questions remain as to how accurately these controlled toxicity tests predict sitespecific bioavailability and effects of metals. Concurrent 42-day Hyalella azteca exposures were performed with cadmium and final treated municipal effluent in the laboratory and at the University of North Texas Stream Research Facility. Further laboratory testing in reconstituted hard water was also conduct… more
Date: August 2003
Creator: Stanley, Jacob K.
Item Type: Refine your search to only Thesis or Dissertation
open access

Macroinvertebrate Colonization and Assemblages Associated with Aquatic Macrophytes in a Newly Created Urban Floodway Ecosystem, Dallas, Tx

Description: A study of macroinvertebrate colonization and assemblages, including secondary productivity of the familiar bluet damselfly or Enallagma civile Hagen (Odonata: Coenagrionidae), associated with the aquatic macrophytes Heteranthera dubia (Jacq.) MacMill. (water stargrass) and Potamogeton nodosus Poir. (American pondweed) was conducted at the Dallas Floodway Extension Trinity River Project (DFE) Lower Chain of Wetlands (LCOW), Dallas, TX, from September 2010 through November 2011. Macroinverte… more
Date: August 2013
Creator: Schad, Aaron Neale
Item Type: Refine your search to only Thesis or Dissertation
open access

Managing Cattail (Typha latifolia) Growth in Wetland Systems

Description: Nutrient availability, water depth, competition, and soil management effects on cattail (Typha latifolia) growth in wetland systems were examined. Soluble reactive phosphorous (SRP), nitrate-nitrogen (NO3-N), and ammonia-nitrogen (NH3-N) removals were tested at a constructed wetland receiving municipal wastewater effluent. Over all, no significant differences in nutrients occurred between diverse planted and cattail areas. T. latifolia seeds, under the canopy of Eleochoris macrostachya, had… more
Date: August 2002
Creator: Sharp, Jessica Little
Item Type: Refine your search to only Thesis or Dissertation
open access

Modeling the Relationship Between Golden Algae Blooms in Lake Texoma, Usa, Versus Nearby Land Use and Other Physical Variables

Description: Pyrmnesium parvum, commonly known as golden algae, is an algal species that under certain circumstances releases toxins which can lead to fish kills and the death of other economically and ecologically important organisms. One of the major objectives of the study was to investigate whether a relationship exists between land use and Prymnesium parvum abundance in littoral sites of Lake Texoma, USA. Another objective was to investigate whether a relationship exists between other physical variable… more
Date: August 2012
Creator: Ware, Trudy M.
Item Type: Refine your search to only Thesis or Dissertation
open access

Recovery of the Fish Population of a Municipal Wastewater Dominated, North Texas Creek After a Major Chlorine Disturbance

Description: This study evaluated the effects of a major chlorine disturbance on fish communities in Pecan creek by the City of Denton's Pecan Creek Water Reclamation Plant. Fish communities in Pecan Creek were sampled using a depletion methodology during February, April, July, and November, 1999. February and April sampling events showed that the fish communities were severely impacted by the chlorine. Sampling during July and November showed fish communities recovered in Pecan Creek. The first-twenty minu… more
Date: August 2002
Creator: Maschmann, Gerald F.
Item Type: Refine your search to only Thesis or Dissertation
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