UNT Theses and Dissertations - 51 Matching Results

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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
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Integration of field-based analysis of plant community dynamics with quantitative analysis of landscape change in the Ray Roberts Lake area, 1987—1997

Description: This study focused on the effectiveness of integrating traditional plant community analyses with landscape ecological analyses based on remotely sensed data. A temporal analysis of plant community diversity was conducted for major plant communities of the Ray Roberts Lake area using transect monitoring data collected between 1987 and 1997. Landscape analyses were performed with FRAGSTATS*ARC using classified SPOT satellite imagery for 1987 and 1997. Although the methodology developed in this wo… more
Date: May 2000
Creator: McDonough, Theresa J.
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Spatial Analysis of Atrazine in the Elm Fork Watershed

Description: This study assessed the water quality of the Elm Fork Watershed with regards to the herbicide Atrazine. Atrazine is a potential environmental endocrine disruptor and carcinogen. Overall, concentrations were lower than the four-quarter drinking water average of 3 µg/Lthe Maximum Contaminant Level set by the USEPA. However, three creek stations had four-quarter average concentrations greater than 3 µg/L, and virtually all samples exceeded the 0.1 µg/L standard set in Europe [1,2]. Statistically s… more
Date: May 2000
Creator: Ochandio, Mario Roberto
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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.
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Assessment of the Efficacy of a Constructed Wetland to Reduce or Remove Wastewater Effluent Estrogenicity and Toxicity Using Biomarkers in Male Fathead Minnows (Pimephales Promelas Rafinesque, 1820)

Description: Vitellogenin in Pimephales promelas was used to assess estrogenicity of a local municipal effluent. Vitellogenin induction in male P. promelas increased in frequency and magnitude with increased exposure duration and was greater ("=0.05) than controls after 2 and 3 weeks of exposure. The level of vitellogenesis induced by effluent exposure was high compared to similar studies. A spring season evaluation followed. Biomarkers in P. promelas were used to assess the efficacy of a treatment wetland … more
Date: December 2000
Creator: Hemming, Jon M.
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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.
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Thresholds in avian communities at multiple scales: Relationships between birds, forests, habitats, and landscapes in the Ray Roberts greenbelt, Denton

Description: Environmental management agencies make efforts to reduce pollution loading in streams and rivers by promoting vegetated buffer zones between human activity and water. Most of these efforts do not mesh water quality-based buffer zone width requirements with conservation and wildlife values, specifically, the use of these riparian forest corridors for wildlife dispersal between habitats in highly fragmented landscapes. Forest interior birds are of the most concern to management in riparian forest… more
Date: December 2000
Creator: Barry, Dwight
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Use of Automated Sampler to Characterize Urban Stormwater Runoff in Pecan Creek

Description: The purpose of this study was to use the Global Water Stormwater Sampler SS201 to characterize the urban runoff in Pecan Creek. Location of the samplers was influenced by land use and ease of installation. Determination of the constituents for analysis was modeled after those used in the NPDES permit for seven cities within the Dallas/Ft.Worth metroplex. Some metals, notably cadmium and arsenic, exceeded the U.S. EPA's MCL's. Statistical analysis revealed first flush samples to be significantly… more
Date: December 2000
Creator: Appel, Patrick L.
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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.
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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
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The Last Laugh: Selected Edwardian Punch Cartoons of Edward Linley Sambourne

Description: The illustrative work of Edward Linley Sambourne for Punch magazine during the period 1901-1910 addresses a myriad of political topics prevalent during the Edwardian period in British history. This thesis examines two of those topics - Women's Suffrage and Socialism - through their artistic treatment by one of Britain's most influential periodicals. Through a study of the historical context and iconography of selected cartoons-of-the-week, one is better equipped to understand and appreciate the… more
Date: May 2001
Creator: Larson, Alison
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Portrait of Your Stream: Development and Assessment of a Stream Ecology Program for Middle-School Student

Description: Portrait of Your Stream (POYS) is a stream ecology and student action program designed for use with middle-school students. The program is correlated with learning cycle pedagogical methods emphasizing student-centered lessons and activities in both classroom and outdoor settings. Implementation of a pilot program in the Fall semester of 1999 was used to collect formal and informal responses and data from students and teachers. Data included changes in student knowledge, skills and attitudes an… more
Date: May 2001
Creator: Swirczynski, Brenda J.
Item Type: Refine your search to only Thesis or Dissertation
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Selection and Use of Aquatic Vegetation by Migratory Waterfowl in North Central Texas

Description: Assessment of aquatic plant selection by waterfowl has been conducted during the winters of 1997-2000 on 49 0.2-0.79 ha research ponds in north central Texas. Ponds were categorized by dominant plant species into eight habitat types. Census with waterfowl species identification were performed to investigate impacts of aquatic vegetation and water depth on waterfowl. Eighteen waterfowl species were observed. Peak migration occurred in late December/early January. Mixed native ponds and mixed nat… more
Date: May 2001
Creator: Smith, JoEtta Kaye
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Spatial and Temporal Patterns of Areal and Volumetric Phytoplankton Productivity of Lake Texoma

Description: Phytoplankton productivity of Lake Texoma was measured for one year from August 1999 to August 2000 for four stations, using the oxygen change method and laboratory incubation. Mean values of the photosynthetic parameters, PBmax and alphaB ranged from 4.86 to 46.39 mg O2.mg Chl-1.hr-1 for PBmax and 20.06 to 98.96 mg O2.mg Chl-1.E-1.m2 for alphaB. These values were in the range to be expected for a highly turbid, temperate reservoir. Estimated gross annual areal productivity ranged from 594 g… more
Date: August 2001
Creator: Baugher, Tessy
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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
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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
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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
Partner: UNT Libraries
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Use of geographic information systems for assessing ground water pollution potential by pesticides in central Thailand

Description: This study employed geographic information systems (GIS) technology to evaluate the vulnerability of groundwater to pesticide pollution. The study area included three provinces (namely, Kanchana Buri, Ratcha Buri, and Suphan Buri) located in the western part of central Thailand. Factors used for this purpose were soil texture, percent slope, primary land use, well depth, and monthly variance of rainfall. These factors were reclassified to a common scale showing potential to cause groundwater co… more
Date: August 2002
Creator: Thapinta, Anat
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Water Quality Aspects of an Intermittent Stream and Backwaters in an Urban North Texas Watershed

Description: Pecan Creek flows southeast through the City of Denton, Texas. Characterized as an urban watershed, the basin covers approximately 63.5 km2. Pecan Creek is an intermittent stream that receives nonpoint runoff from urban landuses, and the City of Denton's wastewater treatment plant, Pecan Creek Water Reclamation Plant, discharges effluent to the stream. Downstream from the City of Denton and the wastewater treatment plant, Pecan Creek flows about 6,000 m through agricultural, pasture, and for… more
Date: August 2002
Creator: Taylor, Ritchie Don
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Ecotoxicological Investigations in Effluent-Dominated Stream Mesocosms

Description: The University of North Texas Stream Research Facility (UNTSRF) was designed to examine contaminant impacts on effluent-dominated stream ecosystems. Stream mesocosms, fed municipal effluent from the City of Denton, TX, Pecan Creek Water Reclamation Plant (PCWRP), were treated with 0, 15 or 140 µg/L cadmium for a 10-day study in August 2000. Laboratory toxicity test and stream macroinvertebrate responses indicated that cadmium bioavailability was reduced by constituents of effluent-dominated str… more
Date: December 2002
Creator: Brooks, Bryan W.
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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
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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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Water Quality Mapping on Lake Texoma USA

Description: The primary objective of this study was to develop and evaluate a system capable of rapid, continuous collection of water quality and locational data on Lake Texoma. Secondary objectives included developing monthly distribution maps for chlorophyll-a, turbidity, and specific conductivity in Lake Texoma and investigating the spatial and temporal relationships between these common water quality indicators. A modified YSI multiprobe was used to develop a system capable of surveying the lake within… more
Date: December 2002
Creator: Mabe, Jeffrey A.
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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.
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