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Pre-impoundment Environmental Study of Ray Roberts Lake

Description: "This report presents the results of the pre-impoundment investigations" of Ray Roberts Lake. The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas… more
Date: December 1987
Creator: University of North Texas. Institute of Applied Sciences.
Item Type: Refine your search to only Book
Partner: UNT Institute of Applied Sciences
open access

Pre-impoundment Environmental Study of Ray Roberts Lake

Description: "This report presents the results of the pre-impoundment investigations" of Ray Roberts Lake. The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas… more
Date: May 1988
Creator: University of North Texas. Institute of Applied Sciences.
Item Type: Refine your search to only Report
Partner: UNT Institute of Applied Sciences
open access

Multivariate Analyses of Amphibian and Reptilian Distribution in Texas

Description: Presence-absence data for amphibians, chelonians, saurians, ophidians, and the terrestrial and aquatic ecological guilds of reptilians were analyzed using multivariate analyses. Geographically consistant distributional patterns were found for all faunal groupings. The correspondence between analyses of the different taxa and guilds was not perfect, but similarities were found. All analyses agreed on the presence of a distinctive region in east Texas. Most analyses also agreed on the presence of… more
Date: August 1988
Creator: Ward, Rocky
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Remote Sensing and GIS for Nonpoint Source Pollution Analysis in the City of Dallas' Western Watersheds

Description: This report describes the findings of a study conducted on the watersheds of "Lake Lewisville, Lake Ray Roberts, Lake Grapevine and the Elm Fork of the Trinity River between Lake Lewisville and Frazier Dam," which are all part of the upper Trinity drainage basin (p. 31). The study examines the potential benefit of "remote sensing and geographic information systems (GIS) for watershed management" in and around Dallas, Texas (p. i).
Date: August 1988
Creator: University of North Texas. Department of Biological Sciences.
Item Type: Refine your search to only Book
Partner: UNT College of Arts and Sciences
open access

Remote Sensing and GIS for Nonpoint Source Pollution Analysis in the City of Dallas' Eastern Watersheds

Description: This report describes the findings of a study conducted on the Eastern Watersheds of Lake Lavon, Lake Ray Hubbard, Lake Tawakoni, Lake Palestine and Lake Fork, which are located within the Blackland Prairie, Post Oak Savannah and Pineywoods provinces. These watersheds are among nine that provide drinking water to Dallas, Texas. The study examines the potential benefit of "remote sensing and geographic information systems (GIS) for watershed management" in these five watersheds (p. iii).
Date: June 1989
Creator: University of North Texas. Department of Biological Sciences.
Item Type: Refine your search to only Book
Partner: UNT College of Arts and Sciences
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Applications of GIS and Remote Sensing for the Characterization of Habitat for Threatened and Endangered Species

Description: Geographic Information Systems (GIS) and remote sensing technologies were used to identify and describe potential habitat for three species endemic to the Southwestern United States; the Golden-cheeked Warbler (Dendroica chrysoparia), the Black-capped Vireo (Vireo atricapillus), and the Texas kangaroo rat (Dipodomys elator). For each species, the computerized classification of digital satellite imagery was integrated with ancillary spatial information (e.g. soils, geology, and land use) to con… more
Date: December 1989
Creator: Shaw, Denice Marie, 1958-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Desorption/Diffusion of Benzene After Simulated Ground Water Remediation

Description: A study was undertaken to examine the desorption/ iffusion of benzene after simulated ground water remediation in aquifer material of differing carbon content using column experiments and comparing the results to batch experiments and adsorption empirical relationships. It was hypothesized that the organic carbon of the aquifer material will affect desorption/diffusion. Results from the column experiment indicated no significant difference in the increase benzene concentrations after remediatio… more
Date: December 1989
Creator: Bennett, Kathryn C. (Kathryn Condreay)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Effects of Water Quality, Instream Toxicity, and Habitat Variability on Fish Assemblages in the Trinity River, Texas

Description: The Trinity River flows through the Dallas-Ft. Worth Metroplex in north central Texas where it receives effluents from numerous point sources including seven large regional wastewater treatment facilities. Historically, the Trinity River has been impacted by massive wastewater loadings which often constitute > 80% of the total river discharge during low flow periods. Normally, high mass loadings correspond to the summer months, compounding the effects of a naturally stressful period, characteri… more
Date: December 1989
Creator: Arnold, Winfred R., 1960-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

The Effect of Nine Diet and Water Combinations on the Culture Health of Ceriodaphnia Dubia

Description: Culture health of Ceriodaphnia dubia was evaluated for organisms cultured using all combinations of three foods and three waters. Criteria used to assess health of cultures included adult and neonate weights, time required to produce first broods, neonate production, adult survival, and resistance to hexavalent chromium. Diet/water combinations which produced the most neonates were not found to produce adults which were more resistant to chromium than those which produced fewer neonates. Of tho… more
Date: May 1990
Creator: Patterson, Paul W. (Paul William)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Sediment Bound Trace Metals in the White Rock Creek Watershed, Dallas and Collin Counties

Description: Areas were sampled in the White Rock Creek Watershed to examine sediment bound trace metal distributions and sorption relationships. A Kruskal-Wallis AOV found significant among area differences for most metals, and SNK-like multiple comparisons were used to group these areas. Kruskal-Wallis AOVs similarly found among area differences for sediment components that bind trace metals (Fe and Mn oxides and organic carbon) and physicochemical conditions that influence metal sorption (particle size a… more
Date: May 1990
Creator: Combest, Kyle B. (Kyle Bryan)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Toxicity of Chromium and Fluoranthene From Aqueous and Sediment Sources to Selected Freshwater Fish

Description: Research efforts in aquatic toxicology have historically centered on the chemical analyses and toxic effects of waters to aquatic organisms. More recently, sediment-source toxicity has been explored, with efforts concentrated on establishing sensitive and accurate methodologies. This study focused on the toxicity of trivalent chromium, hexavalent chromium, and fluoranthene to Pimephales promelas, Ictalurus punctatus, and Lepomis macrochirus. Test fish were exposed to both water-borne and sedime… more
Date: May 1990
Creator: Gendusa, Tony C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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An Analysis of Refuse Derived Fuel as an Environmentally Acceptable Fuel Alternative for the Cement Industry

Description: Resource recovery is an attractive alternative to the waste disposal problem. The chief by-product of this process, refuse derived fuel (RDF) can be co-fired in traditional coal burning facilities. The cement industry is a potential user of RDF. This study, based on a test burn done at Texas Industries Inc. in Midlothian, Texas, demonstrated the technical, environmental, and economic feasibility of using RDF fuel in a cement kiln. Technically, the cement showed no deleterious effects when RDF w… more
Date: May 1991
Creator: Brooks, Cheryl L. (Cheryl Leigh)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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After Earth Day: Continuing the Conservation Effort

Description: Collection of essays based on sessions presented at a conference held for the 21st Earth Day (April 1991), organized into five topical sections: Conservation Politics; Environmental Science Today and Tomorrow; Conservation, Economics, and the Corporate Effort; Environmental Philosophy; and Religion and Conservation. Index starts on page 237.
Date: 1992
Creator: Oelschlaeger, Max
Item Type: Refine your search to only Book
Partner: UNT Press
open access

Atmospheric Visibility Assessment for Urban Areas Using Photographic Slides and Optical Densitometry

Description: The factors involved in calculating Standard Visual Range (SVR) are discussed, and a comparison is made between the visibility reported by airport observers and the photographic slide/ optical densitometer method of calculating SVR. Using slides of Houston, Texas, from the fall and winter of 1988-89, it was found that the altitude at which the contrast measurements are made significantly affects the SVR. Also an index for predicting high and low humidity was developed using the blue/red ratio o… more
Date: May 1992
Creator: Jacob, Mary Katherine
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Ephippia Production, Activation, and Use of Ex-Ephippio Neonates of Ceriodaphnia Dubia as Toxicity Test Organisms

Description: Ceriodaphnia dubia is widely used as a test organism in monitoring water quality. At the present time, cultures must be continuously maintained in the laboratory. In an attempt to avoid continuous culture and maintenance, the hatching of ephippial eggs of C. dubia would provide test organisms when needed. In order to determine the parameters required for maximum hatching, approximately ninety-four thousand ephippia were exposed to a variety of conditions ranging from light and temperature regim… more
Date: August 1992
Creator: Poage, Duane W.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Development of Predictive Models for the Acid Degradation of Chrysotile Asbestos

Description: The purpose of this study was to determine the factors affecting the acid degradation of chrysotile asbestos (Mg_3Si_2O_5(OH_4)) . Millions of tons of asbestos have found use in this country as insulative or ablative material. More than 95 percent of the asbestos in use is of the chrysotile variety. The remaining 5 percent is composed of various types of fibrous amphiboles. The inhalation of asbestos can lead to several diseases in humans. Asbestosis, lung cancer and mesothelioma are the most c… more
Date: May 1993
Creator: Ingram, Kevin D. (Kevin Dean)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Eutrophication Monitoring and Prediction

Description: Changes in trophic status are often related to increases or decreases in the allocthonous inputs of nutrients from changes in land use and management practices. Lake and reservoir managers are continually faced with the questions of what to monitor, how to monitor it, and how much change is necessary to be considered significant. This study is a compilation of four manuscripts, addressing one of these questions, using data from six reservoirs in Texas.
Date: December 1993
Creator: Cairns, Stefan H., 1949-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Habitat Evaluation Procedures at Ray Roberts Lake: an Analysis of the Relationship with Ecological Indicators and a Study of Observer and Temporal Variability

Description: Habitat Evaluation Procedure data gathered at Ray Roberts Lake in 1989 and 1990 were analysed for temporal variability, observer variability and relationships between Habitat Units (HUs) and species density/diversity. observer variability within a group was analysed by cluster analysis and bootstrapping. Five out of 36 sites showed significant differences in Habitat Suitability Index (HSI) values within the group. A nonparametric Mann-Whitney test was used to analyze temporal variability. One o… more
Date: December 1993
Creator: Wattrus, Jane M. (Jane Marie)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Landscape Ecological Characteristics of Habitat of the Red-cockaded Woodpecker

Description: Geographic information systems (GIS) technology was used to analyze factors influencing habitat use by an endangered species, the red-cockaded woodpecker. The study area was the western part of the Raven Ranger District of the Sam Houston National Forest, Texas. The factors considered included both structural characteristics and spatial relationships among stands of trees in the habitat.
Date: December 1993
Creator: Thomlinson, John Richard
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Temporal and Spatial Comparisons of Ambient Toxicity of the Trinity River in Relationship to an Effluent

Description: A toxicological study was initiated because of concerns about allegations that the Texas Water Commission that effluent from the Dallas Central Wastewater Treatment Plant, which discharges into the Trinity River, was affecting downstream water quality. Monthly, flow-weighted composite effluent samples were collected. Grab samples were also collected upstream and downstream from the effluent from April 1989 to August 1991. Toxicity tests were conducted on these samples using Ceriodaphnia dubia a… more
Date: December 1993
Creator: Hall, David B., 1958-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Multiple Regression Equations to Estimate Mean Nutrient Concentrations in Streams of North Central Texas from Landsat Derived Land Use

Description: Nutrients are of critical concern in water quality assessment. The development of empirical models to estimate mean nutrient concentrations, based on satellite derived land use, could aid water resource managers. Models using land use acreages outperformed those using percentages, and discrete urban land uses were superior to lumped urban. Regressions of the combinations of two, three and four of the eight possible land use variables were investigated. Sensitivity analyses, with one stream dele… more
Date: May 1994
Creator: Kerr, Barry Douglas
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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SFE Fractionation and RP-HPLC Characterization of Aquatic Fulvic Acid

Description: The Supercritical Fluid Extraction (SFE) technique was used to fractionate Suwannee River reference fulvic acid (FA). The fractions were characterized by gas chromatography (GC) and reversed-phase high performance liquid chromatography (RP-HPLC). A SFE fractionation method was developed using stepwise gradient of supercritical CO₂ and methanol. Three FA fractions were separated. The average mass recovery was 102% with the coefficient of variation of 2.8%. The fractionation dynamics and the diff… more
Date: May 1994
Creator: Shao, Peimin
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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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
Partner: UNT Libraries
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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
Partner: UNT Libraries
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