Description: The dissertation is a philosophical approach to politicizing place and space, or environments broadly construed, that is motivated by three questions. How can geography be employed to analyze the spatialities of environmental justice? How do spatial concepts inform understandings of environmentalism? And, how can geography help overcome social/political philosophy's redistribution-recognition debate in a way that accounts for the multiscalar dimensions of environmental justice? Accordingly, the dissertation's objective is threefold. First, I develop a critical geography framework that explores the spatialities of environmental injustices as they pertain to economic marginalization across spaces of inequitable distribution, cultural subordination in places of misrecognition, and political exclusion from public places of deliberation and policy. Place and space are relationally constituted by intricate networks of social relations, cultural practices, socioecological flows, and political-economic processes, and I contend that urban and natural environments are best represented as "places-in-space." Second, I argue that spatial frameworks and environmental discourses interlock because conceptualizations of place and space affect how environments are perceived, serve as framing devices to identify environmental issues, and entail different solutions to problems. In the midst of demonstrating how the racialization of place upholds inequitable distributions of pollution burdens, I introduce notions of "social location" and ...

Description: The effectiveness of behavioral interventions for the treatment of young children with autism has been well documented in professional literature. The success of these procedures, however, depends on the fidelity of implementation and proper training of the therapist. The purpose of this study was to evaluate a 125-skill, comprehensive staff training package that involved a graduated sequence of teaching. In addition to changes in skills, social validity and training time were also assessed. Results indicate that correct demonstration of skills increased following training, incorrect implementation decreased, teachers rated the procedures favorably, and the total training took between 20 and 32.5 hours for over 120 skills to reach mastery criteria. A discussion of the results as well as implications for future research is also provided.

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 funnel traps were constructed (four reps of each type: control, dual-walled and ring cage). Two anti-escape devices were tested with funnels including steel fingers and hinged flaps. Ring cage and dual-walled treatments were planted using native pondweeds, while controls were left unplanted (additional bait and a drift fence scenarios were also tested). Common carp were introduced into the study pond. Chi-square statistical analyses were utilized and showed ring cage treatments using fingers as well as the use of a drift fence to be most effective. Following completion of the pond study, the two most effective treatments (controls and ring cages) were tested within the Dallas, Texas wetland; no carp were caught during the field test.

Description: Triclosan (TCS) and triclocarban (TCC) are antimicrobials found in U.S. surface waters. This dissertation assessed the effects of TCS and TCC on early development and investigated their potential to bioaccumulate using Xenopus laevis as a model. The effects of TCS on metamorphosis were also investigated. For 0-week tadpoles, LC50 values for TCS and TCC were 0.87 mg/L and 4.22 mg/L, respectively, and both compounds caused a significant stunting of growth. For 4-week tadpoles, the LC50 values for TCS and TCC were 0.22 mg/L and 0.066 mg/L; and for 8-week tadpoles, the LC50 values were 0.46 mg/L and 0.13 mg/L. Both compounds accumulated in Xenopus. For TCS, wet weight bioaccumulation factors (BAFs) for 0-, 4- and 8-week old tadpoles were 23.6x, 1350x and 143x, respectively. Lipid weight BAFs were 83.5x, 19792x and 8548x. For TCC, wet weight BAFs for 0-, 4- and 8-week old tadpoles were 23.4x, 1156x and 1310x. Lipid weight BAFs were 101x, 8639x and 20942x. For the time-to-metamorphosis study, TCS showed an increase in weight and snout-vent length in all treatments. Exposed tadpoles metamorphosed approximately 10 days sooner than control tadpoles. For the hind limb study, although there was no difference in weight, snout-vent length, or hind limb ...

Description: This study elucidates the underlying relationships for the distribution of oak landcover on bedrock and soil orders in two counties in Texas and one in Oklahoma. ESRI's ArcGis and ArcMap was used to create surface maps for Denton and Coke Counties, Texas and Choctaw County, Oklahoma. Attribute tables generated in GIS were exported into a spreadsheet software program and frequency tables were created for every formation and soil order in the tri-county research area. The results were both a visual and numeric distribution of oaks in the transition area between the eastern hardwood forests and the Great Plains. Oak distributions are changing on this transition area of the South Central Plains. The sandy Woodbine and Antlers formations traditionally associated with the largest oak distribution are carrying oak coverage of approximately 31-32% in Choctaw and Denton Counties. The calcareous Blackland and Grand Prairies are traditionally associated with treeless grasslands, but are now carrying oak and other tree landcover up to 18.9%. Human intervention, including the establishment of artificial, political and social boundaries, urbanization, farming and fire control have altered the natural distribution of oaks and other landcover of this unique georegion.