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open access

Analysis and Development of Post Secondary Curriculum on Sustainability

Description: This thesis examines existing curricula at colleges and universities about sustainability and uses results to develop an introductory post secondary course curriculum. The proposed course is organized around three major elements - - science, philosophy, and economics - - all integral to understanding sustainability. Materials needed to teach the proposed 3-semester hour course including syllabus, teaching modules, transparencies, handouts, and exams were developed. Suggestions on how to teach a… more
Date: May 2000
Creator: White, Miki Machell
open access

Analysis of the One-Horned Rhinoceros (Rhinoceros Unicornis) Habitat in the Royal Chitwan National Park, Nepal.

Description: This study analyzes the remaining suitable habitat of the one-horned rhinoceros, Rhinoceros unicornis, in Royal Chitwan National Park of Nepal. An April 2003 Landsat image was classified into eight land cover types: wetland, sand, water, mixed forest, sal forest, agriculture, settlement, and grassland. This image was converted into habitat suitability maps using cover, food, and water. The rhinoceros prefers grassland habitat with oxbow lakes and closed canopy during the monsoon season. Nomina… more
Date: December 2005
Creator: Thapa, Vivek
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
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.
open access

Bioaccumulation of Triclocarban, Triclosan, and Methyl-triclosan in a North Texas Wastewater Treatment Plant Receiving Stream and Effects of Triclosan on Algal Lipid Synthesis.

Description: Triclosan (TCS) and triclocarban (TCC), widely used antimicrobial agents found in numerous consumer products, are incompletely removed by wastewater treatment plant (WWTP) processing. Methyl-triclosan (M-TCS) is a more lipophilic metabolite of its parent compound, TCS. The focus of this study was to quantify bioaccumulation factors (BAFs) for TCS, M-TCS, and TCC in Pecan creek, the receiving stream for the City of Denton, Texas WWTP by using field samples mostly composed of the alga Cladophor… more
Date: August 2007
Creator: Coogan, Melinda Ann
open access

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

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 Eva… more
Date: May 2002
Creator: Roberts, Elizabeth
open access

Comparison of Bare Root vs. Potted Plants, Species Selection, and Caging Types for Restoration of a Prairie Wetland, and Quantitative Analysis and Descriptive Survey of Plant Communities and Associations at Lewisville Lake Environmental Learning Area (LLELA), Lewisville, TX

Description: Lewisville Lake Environmental Learning Area (LLELA) is an 809-hectare property in Denton County, TX. A study of the vegetation community identified 466 species in 104 families, with 25% of the species from only two families, Asteraceae and Poaceae. The property demonstrates the characteristics of an early successional community, dominated by weedy species. Prairie communities are dominated by Johnson grass and ragweed, with climax tall grass prairie communities only in areas that have been plan… more
Date: May 2007
Creator: Buckallew, Robin R.
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
open access

Correspondence Between Aquatic Ecoregions and the Distribution of Fish Communities of Eastern Oklahoma

Description: I assessed fish community data collected by the Oklahoma Conservation Commission from 82 minimally impaired wadeable reference streams in eastern Oklahoma to determine whether existing aquatic ecoregions provide the best framework for spatial classification for the development of biological assessment methods and biocriteria. I used indirect ordination and classification to identify groups of sites that support similar fish communities. Although correspondence was observed between fis… more
Date: May 2001
Creator: Howell, Charles E.
open access

Density, Distribution and Habitat Requirements for the Ozark Pocket Gopher (Geomys Bursarius Ozarkensis)

Description: A new subspecies of the plains pocket gopher (Geomys bursarius ozarkensis), located in the Ozark Mountains of north central Arkansas, was recently described by Elrod et al. (2000). Current range for G. b. ozarkensis was established, habitat preference was assessed by analyzing soil samples, vegetation and distance to stream and potential pocket gopher habitat within the current range was identified. A census technique was used to estimate a total density of 3, 564 pocket gophers. Through automo… more
Date: May 2004
Creator: Kershen, Audrey Allbach
open access

Determination of Habitat Preferences of Pronghorn (Antilocapra americana) on the Rolling Plains of Texas Using GIS and Remote Sensing

Description: The Rocker b Ranch on the southern Rolling Plains has one of the last sizeable populations of pronghorn (Antilocapra americana) in Texas. To investigate habitat utilization on the ranch, pronghorn were fitted with GPS/VHF collars and were released into pastures surrounded by a variety of fences to determine how fence types affected habitat selection. Habitat parameters chosen for analysis were vegetation, elevation, slope, aspect, and distances to water, roads, and oil wells. Results showed … more
Date: May 2005
Creator: Aiken, Robin A.
open access

Dissolved Organic Carbon Assessment on Selected Creeks and Rivers within the Elmfork Subwatersheds of Denton, Texas

Description: The primary focus of the study was to compare dissolved organic carbon (DOC) at baseline stream flow to DOC at a higher post-rain stream flow, with a secondary focus on comparison of DOC between sites. Comparisons were also done on suspended solids at baseline flow to those of the higher post-rain flow, as well as suspended solids between sites. Significant differences did exist between DOC sampled at baseline flow and DOC in samples taken at peak flow. The study found no difference in suspende… more
Date: May 2004
Creator: Jackson, Pamela J.
open access

Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles

Description: This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the h… more
Date: May 2002
Creator: Redick, Melinda
open access

Effects on Survival, Reproduction and Growth of Ceriodaphnia dubia following Single Episodic Exposure to Copper or Cadmium

Description: Effects of episodic exposures have gained attention as the regulatory focus of the Clean Water Act has shifted away from continuous-flow effluents. Standardized laboratory toxicity tests require that exposure be held constant. However, this approach may not accurately predict organism responses in the field following episodic exposures such as those associated with rain-driven runoff events or accidental pollutant discharge. Using a modified version of the 7-day short-term chronic test recomme… more
Date: August 2005
Creator: Turner, Philip K.
open access

Establishment and Competitive Ability of Nelumbo Lutea in Relation to Myriophyllum Spicatum

Description: Limitations from reduced light and increasing water depth on Nelumbo lutea seedlings were determined in tank experiments. Survival was high in all tested light levels. Total biomass increased significantly with increasing light. Biomass allocation shifted significantly to root production between 3 and 6 weeks in the 10 and 24% levels. Survival decreased with increasing planting depth, and biomass of survivors reduced significantly between 0.5, 1.0, and 1.5 m depths. Nelumbo lutea and Myriophyl… more
Date: December 2000
Creator: Snow, Joe R.
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
open access

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

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 funne… more
Date: May 2008
Creator: Williams, Paul Edwin
open access

Evaluation of the Chlorophyll/Fluorescence Sensor of the YSI Multiprobe: Comparison to an Acetone Extraction Procedure

Description: The purpose of this study was to examine the suitability of the YSI model 6600 Environmental Monitoring System (multiprobe) for long term deployment at a site in Lewisville Lake, Texas. Specifically, agreement between a laboratory extraction procedure and the multiprobe chlorophyll/fluorescence readings was examined. Preliminary studies involved determining the best method for disrupting algal cells prior to analysis and examining the precision and linearity of the acetone extraction procedur… more
Date: May 2001
Creator: Lambert, Patricia
open access

Evaluation of the Economic, Social, and Biological Feasibility of Bioconverting Food Wastes with the Black Soldier Fly (Hermetia illucens)

Description: Food waste in the waste stream is becoming an important aspect of integrated waste management systems. Current efforts are composting and animal feeding. However, these food waste disposal practices rely on slow thermodynamic processes of composting or finding farmers with domestic animals capable of consuming the food wastes. Bioconversion, a potential alternative, is a waste management practice that converts food waste to insect larval biomass and organic residue. This project uses a native a… more
Date: August 2004
Creator: Barry, Tami
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
open access

The impact of climate and flooding on tree ring growth of Fraxinus pennsylvanica in north-central Texas.

Description: Tree cores of Fraxinus pennsylvanica were used in a dendrochronological analysis investigating the species' responses to climate and flooding. The objective was to develop a model that incorporates the effects of precipitation, temperature, and flooding on radial growth in this species in north-central Texas. The trees exhibited strong climatic signals. The study clearly shows that all three factors have significant impacts on tree ring growth both prior to and during growth; however, the natur… more
Date: December 2009
Creator: Komperod, Mari
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
open access

Investigation of Lead Hydrolytic Polymerization and Interactions with Organic Ligands in the Soil/Sediment-Water Environment

Description: The objective of this research was to investigate lead speciation in the soil/sediment-water environment and to better understand how the species affect lead mobility under different environmental conditions. The research involved both field soil and sediment samples as well as standard lead solutions. Field samples were fully characterized and extracted by aqueous and organic solvents. The results were compared and evaluated with the metal speciation model, MINTEQA2. Hydrolytic polymerization … more
Date: December 2002
Creator: Sanmanee, Natdhera
open access

Landscape forest modeling of the Luquillo Experimental Forest, Puerto Rico.

Description: This thesis contributes to modeling the dynamics of forest community response to environmental gradients and disturbances over a mountain landscape. A gap model (FACET) was parameterized for species of various forest types (Tabonuco, Colorado, Dwarf and Palm), for many terrain conditions and was modified and extended to include species response to excess soil moisture and hurricanes. Landscape cover types were defined by dominance of species of each forest type and canopy height. Parameters of … more
Date: December 2002
Creator: Abbott-Wood, Chris
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