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open access

Plankton Community Response to Dechorination of a Municipal Effluent Discharged into the Trinity River

Description: Chorine is used by the Village Creek Waste Water Treatment Plant to kill pathogenic microorganisms prior to discharge of the effluent into the Trinity River. The residual chlorine in the river impacted aquatic life prompting the U.S. Environmental Protection Agency in December 1990 to require dechlorination using sulfur dioxide. One pre-dechlorination and four post-dechlorination assessments of phytoplankton, periphyton, and zooplankton communities were conducted by the Institute of Applied Sci… more
Date: December 1994
Creator: Bryan, Brynne L. (Brynne Lee)
open access

An Evaluation of Fish and Macroinvertebrate Response to Effluent Dechlorination in Pecan Creek

Description: This study evaluated the effects of chlorinated effluent discharged from the City of Denton, Texas' wastewater treatment plant on Pecan Creek's fish and macroinvertebrate assemblages, and their recovery upon dechlorination. A baseline of ecological conditions was established while chlorine was present in the effluent (June 1993- October 1993), and was evaluated again after dechlorination with sulfur dioxide (October 1993-August 1994). In situ Asiatic clam and fathead minnow ambient toxicity tes… more
Date: May 1995
Creator: Wise, Patricia D. (Patricia Diane)
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)
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
open access

The Tarrant County Atlas for Planning: A Geographic Information System for Open Space Design

Description: This project demonstrates the construction of a land planning geographic information system (GIS) for Tarrant County, and explores how the technology could be used to select sites for a county wide open space preservation plan. As Texas' Tarrant County continues to undergo rapid change due to growth and expansion, the need for proactive, resourceful community planning is greater than ever. One crucial issue facing the region is how to preserve open areas that serve the county's citizens' ecolog… more
Date: May 1996
Creator: Stewart, Mark Pierce
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)
open access

Simulating Thermal and Chemical Spills in Coupled Cooling Reservoirs

Description: Hot water discharges and potential chemical spills are factors that threaten water quality in cooling reservoirs of chemical and power plants. In this thesis, three models are used to analyze the impact of these factors in a particular case study.
Date: August 1997
Creator: Qiu, Bin
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)
open access

Environmental Factors Influencing Chlorophyll-a Concentrations in Lake Texoma

Description: An analysis of algal biomass measured by chlorophyll-a concentration in Lake Texoma was performed as a part of a monitoring program to develop baseline environmental data in order to detect the potential effects of engineered changes in chloride concentrations in the reservoir. This portion of the research project focused on two main research objectives. The first objective was evaluating the effect of sampling strategy on the ability to adequately reflect standing crop estimates and trends in … more
Date: December 1998
Creator: Gibbs, Jennifer S. (Jennifer Sokolovic)
open access

Pretreatment Optimization of Fiberglass Manufacturing Industrial Wastewater

Description: Wastewater effluent produced in the fiberglass manufacturing industry contains a significant amount of total suspended solids. Environmental regulations require pretreatment of effluent before it is discharged to the municipal wastewater treatment plant. Chemical precipitation by coagulation and flocculation is the method of pretreatment used at the Vetrotex CertainTeed Corporation (VCT). A treatability study was conducted to determine conditions at which the VCT Wastewater Pretreatment Plant c… more
Date: December 1998
Creator: Dragoo, Ron
open access

Interspecific Competition Between Hygrophila polysperma and Ludwigia repens, Two Species of Importance in the Comal River, Texas

Description: Hygrophila polysperma is a plant native to Asia that has been introduced into the Comal River, TX and is thriving while Ludwigia repens, a species native to the river appears to be declining. Both plants have similar morphologies and occupy similar habitats in the river. Two plant competition experiments were conducted to examine the competitive interactions between the two species. First, an experimental design was developed in which established Ludwigia plants were 'invaded' by sprigs of Hygr… more
Date: May 1999
Creator: Francis, Matthew D.
open access

Monitoring Watershed Health in the Upper Trinity River Basin, North Central Texas

Description: This study conducts watershed analysis using biological and geo-spatial techniques. Incorporating landscape features with biological attributes has been shown to be an effective method of monitoring environmental quality within watersheds. In situ biomonitoring using the Asiatic Clam, Corbicula fluminea, habitat suitability, and water quality data were evaluated for their potential to describe ecological conditions in agricultural and urban areas within the Upper Trinity River watershed. These … more
Date: May 1999
Creator: Csekitz, Jill Diane
open access

An Assessment of the Use of Seeding, Mowing, and Burning in the Restoration of an Oldfield to Tallgrass Prairie in Lewisville, Texas

Description: An examination of the effectiveness of seeding, burning, and mowing in the reestablishment of tallgrass prairie species on overgrazed and abandoned pastureland. The study site is a 20 acre tract on U.S. Corps of Engineers land below Lake Lewisville in Denton County, Texas. The site was partitioned into thirty-nine 40 by 40 meter plots with seeding (carried out in 1996) and management treatment (burning, mowing, and no maintenance carried out in 1998) randomly applied following a two level desig… more
Date: August 1999
Creator: Windhager, Steven
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