ArcView and ArcInfo were used to identify and delineate areas contaminated by fluoride, sulfate, chloride, and nitrate in the Woodbine Aquifer. Water analysis data were obtained from the TWDB from the 1950s to 1990s covering 9 counties. 1990s land use data were obtained to determine the relationship with each contaminant. Spearman's rank correlation coefficients and Kruskal-Wallis tests were used to calculate relationships between variables. Land uses had little effect on distributions of contaminants. Sulfate and fluoride levels were most problematic in the aquifer. Depth and lithology controlled the distributions of each contaminant. Nitrate patterns were controlled mainly by land use rather than geology, but were below the maximum contaminant level. In general, contaminant concentrations have decreased since the 1950s.

The four elements of the lower hind foot (calcaneus, metatarsal, naviculo-cuboid, and tibia) were tested for use as age-independent proxies of body size in white-tailed deer using known aged specimens from Ft. Hood Texas. Statistical analysis indicates that the calcaneum and the tibia are good proxies of age-independent body size in white-tailed deer. In addition to expanding the list of elements that can be used for studies of age-independent body size, these elements can also be used to age faunal remains to an ordinal scale of juveniles and adults. This is useful for research regarding prehistoric prey populations; as a single element can be used to determine prey body size and age simultaneously, which are the two variables used to assess changes in human subsistence practices via the archaeological remains of their prey.

Rain gardens are low impact developments designed to mitigate a suite of issues associated with urban stormwater runoff. The site for this study was a Denton City rain garden at the Denton Waste Water Treatment Plant. Nitrogen and phosphorus removal was examined in light of two overflow events comprised of partially treated wastewater from an upslope anaerobic digester pond. Nitrate removal efficiency was examined across differing dry spell intervals of 5, 8, and 12 d, displaying a moderate negative correlation (r2 = 0.59). Continued phosphorus removal capacity was assessed, showing phosphorus removal in cases where P was in excess of 0.8 mg/L, reflecting an equilibrium phosphorus concentration. A high expanded shale component in the soil media (25%) was likely a factor in the continued removal of phosphorus. Overall the rain garden proved to be a large source of nitrate (+425%) and total nitrogen (+61%) by mass. The study showed that while the rain garden intercepted a large volume of partially treated wastewater during the overflow events, preventing it from reaching a nearby creek, the mitigation of an acute event has extended to a chronic one as nitrogen is gradually processed and flushed from the system as nitrate.

Urbanization is seen as a threat to biodiversity within urban ecosystems, which are largely reliant on humans for their composition. Two types of extremes exist in the spectrum of urban domestic gardens; on one end, the typical urban garden which is planted by landscapers at the time the house is built and is generally left unchanged, and, at the other, a "wild" landscape planted entirely with native plants which provides habitat for native fauna and pollinators. This study assesses the plant choices made by members of organized gardening groups-the Denton County Master Gardeners (DCMG), the Elm Fork Master Naturalists (EFMN), the Trinity Forks Native Plant Society (TFNPS), and Keep Denton Beautiful (KDB)-and toward which extreme these choices put these gardens on the psectrum. TFNPS and EFMN both fall closer to the wild garden extreme, with TFNPS the closest to a "wild garden." DCMG was almost directly between the two extremes, but fell closer to the typical urban garden. By looking at how these groups manage their gardens, we begin to understand the ways in which gardeners can mitigate and soften the harsh changes between wild landscapes and urban environments. Collaboration between groups could have the potential to encourage more people …

Many factors have prompted the adoption of partial-market exit strategies in retail as a means of reducing cost and minimizing risk. These mass closures have become more frequent in recent years. Marketers and economists have offered explanations for these closures linked to the rise of e-commerce, the real estate cycle and general changes in consumer taste. The research here marks an attempt to apply geospatial and econometric methods to better understand what factors explain the spatial variation of these closures across the United States. Specifically, the analysis examines the store networks of Sears, J.C. Penney and Macy's- large, established department stores that, collectively, announced over 100 closures at the beginning of 2017. By treating each store as a unit of observation, and a closure as a limited dependent variable, this analysis will attempt to quantify the relationship between place-specific factors and retail closures using Probit modeling. This application of modeling marks a deviation from traditional analyses in retail geography which, up until the early 2000s, have focused almost entirely on store development and growth. The results reveal patterns of spatial clustering of closures in and around the Rust Belt and demonstrate the strong negative effect of competitive agglomeration on the …

The analysis of protein residues recovered from archaeological artifacts provides a unique opportunity to reveal new information about past societies. However, many scientists are currently unwilling to accept protein-based results due to problems in method development and a basic lack of agreement regarding the ability of proteins to bind to, and preserve within, artifacts such as pottery. In this paper, I address these challenges by conducting a two-phase experiment. First, I quantitatively evaluate the tendency of proteins to sorb to ceramic matrices by using total organic carbon analysis and spectrophotometric assays to analyze samples of experimentally cooked ceramic. I then test a series of solvent and physical parameters in order to develop an optimized method for extracting and preparing protein residues for identification via mass spectrometry. Results demonstrate that protein strongly sorbs to ceramic and is not easily removed, despite repeated washing, unless an appropriate extraction strategy is used. This has implications for the future of paleodietary, conservation ecology and forensic research in that it suggests the potential for recovery of aged or even ancient proteins from ceramic matrices.

Renewable energy studies are becoming increasingly important as world energy demand rises and current energy sources are increasingly questioned. Solar photovoltaics (PV) are the focus of this study as a renewable industry still in its infancy. This research examines the geography of solar panel installation and manufacturing from 2007 to 2010 in California and New York. California is the larger of the two markets and has implemented more policy support; programs that appear to have increased the pace of installations, reduce the size of the subsidy, and help lower total costs. Similar trends are observable in New York. US based companies are still making solar panels, but foreign competitors, most notably from China and Mexico, are capturing an increasing share of the market.

This research is an investigation of the Late Holocene technological transition from the spearthrower and dart to the bow and arrow in north central Texas. It is conducted through a theoretical approach that utilizes ethnographic research, experimental archaeology and the archaeological record to elucidate differences in the behaviors and hunting strategies of Late Archaic and Late Prehistoric groups. It first confirms that there was a transition. Second, a lithic analysis demonstrates that there are fundamental differences in the sizes of the stone dart and arrow points that relate to the propulsive requirements of the weapon systems. Third, it is shown these size differences constrain maintenance potentials and that indeed dart and arrow points exhibit stark differences in their life histories in spite of being employed for the same task. And finally, the faunal record suggests that this transition was associated with an increase in foraging efficiency.

Mass transit investments continue to be utilized in many cities as means of dealing with various transportation issues. In Dallas Texas, light rail transit was developed with the hopes of encouraging compact and orderly growth. This research uses the DART system as a case study in examining transportation/land use relationships in Dallas. As such, this thesis reviews past research that examined transit systems impacts on urban areas, analyzes historical changes in land use pattern development around the existing twenty stations of the DART light rail starter system, and summarizes the progression of land use trends in the transit corridor as they relate to DART impacts. Results of this study suggest that DART's light rail system has been an effective tool used in achieving the transportation and land use goals for the region. Finally, recommendations are presented with respect to what can be expected for future light rail development in Dallas.

This thesis interrogates sense of place and place attachment in the Big Empty on the north central Texas plains. The region stretches from the Red River on the north to the Colorado River basin on the south and from the Cross Timbers on the east to the Caprock escarpment on the west. Since 1930, the Big Empty has seen sustained and severe population decline such that some counties there now register less than a quarter the population they did at their peaks during the interwar years. Through in-depth field interviews, I examine sense of place and place attachment amidst apparently irreversible decline. I also describe conditions of postindustrial rurality arising from rolling reconfigurations of economic and social relations, particularly changes in scale in farming and the diminished centrality of productivist agriculture in local economies and culture, and how these conditions become legible through the study of place.

Academic institutions have recently organized to address their campus' greenhouse gas emissions. Along those lines, the University of North Texas (UNT) pledged to minimize the campus' environmental impact, and conducted a transportation survey in May 2009. The analyses confirm that commuting to campus was the second highest source (29%) of UNT's greenhouse gas emissions, following purchased electricity (48%). Students, faculty and staff drive over 89 million miles per year, 84% of which comes from students. Forty‐two percent of student driving trips originate in the primary and secondary core areas surrounding Denton, which are partially served by buses. However, because these core areas are in close proximity to the campus, they contribute only 8% of the total student driving distance. Beyond the Denton core, the inner periphery of Denton County contributes another 22% of driving mileage. Students living in the outer periphery (outside Denton County) contribute the remaining 70% of total driving distance, and carpooling is currently their only alternative.

Population estimation in inter-censual years has many important applications. In this research, high-resolution pan-sharpened IKONOS image, LiDAR data, and parcel data are used to estimate small-area population in the eastern part of the city of Denton, Texas. Residential buildings are extracted through object-based classification techniques supported by shape indices and spectral signatures. Three population indicators -building count, building volume and building area at block level are derived using spatial joining and zonal statistics in GIS. Linear regression and geographically weighted regression (GWR) models generated using the three variables and the census data are used to estimate population at the census block level. The maximum total estimation accuracy that can be attained by the models is 94.21%. Accuracy assessments suggest that the GWR models outperformed linear regression models due to their better handling of spatial heterogeneity. Models generated from building volume and area gave better results. The models have lower accuracy in both densely populated census blocks and sparsely populated census blocks, which could be partly attributed to the lower accuracy of the LiDAR data used.

A traditional two dimensional (planar) statistical analysis was used to identify the clustering types of North Central Texas traffic fatalities occurring in 2001-2006. Over 3,700 crash locations clustered in ways that were unlike other researched regions. A two dimensional (x and y coordinates) space was manipulated to mimic a one dimensional network to identify the tightest clustering of fatalities in the nearly 400,000 crashes reported from state agencies from 2003-2006. The roadway design was found to significantly affect crash location. A one dimensional (linear) network analysis was then used to measure the statistically significant clustering of flow variables of after dark crashes and daylight crashes. Flow variables were determined to significantly affect crash location after dark. The linear and planar results were compared and the one dimensional, linear analysis was found to be more accurate because it did not over detect the clustering of events on a network.

Nutritional quality and availability is thought to regulate geographic patterns of variability in animal body size due to phenotypic plasticity. The purpose of this study is to determine how vegetation quality, abundance and population density influence white-tailed deer (Odocoileus virginianus) body size on a subregional spatial scale at Fort Hood, Texas. Harvest and census records are used to test the hypothesis that white-tailed deer exhibit phenotypic plasticity (e.g. larger body size) in response to differences in vegetation quality and availability. Results from these analyses suggest that forage quality and abundance alone is not a main driver of white-tailed deer body size. Analysis of deer population density (generally) resulted in an inverse relationship with body size. Areas with high quality forage and low population density support larger deer while areas with low quality forage and high density support smaller than average deer. The few exceptions occur in areas exhibiting poor quality forage and low population density or high forage quality and high density. Results from this study suggest that continued overcrowding of deer within isolated areas may eventually lead to efficiency phenotypic conditions producing smaller sized deer. These results could prove useful in interpreting deer population responses to harvest management. For …

Valley development through erosional processes typically tends to create symmetrical valleys. Over time, water cuts through the substrate to create valleys, gorges, and canyons for which the sides are the valley are evenly sloped. However, there are anomalies to this process. Asymmetrical valleys have been well-documented even in areas of uniform substrate or little tectonic uplift. One proposed explanation for the asymmetry of these valleys is differential insolation. This may lead to different microclimates from one slope to another which alter the rate and extent of erosion. Since the differences in received insolation vary with latitude (especially in streams that flow along an east/west axis), it follows that the degree of asymmetry should also vary with latitude if differential insolation is a primary driving factor in the development of these valleys. To evaluate if insolation plays a role in the development of asymmetrical valleys, this study examines variability in asymmetry across 447 valleys in nine study areas located at different latitudes. The degree of asymmetry for each valley was measured by using 30 meter resolution digital elevation models (DEMs) to determine the slope angle of each side of the valley. Asymmetry was measured by computing a ratio of the average …

This study is a test of a methodology to predict changes in elevation and shoreline position of coastal wetlands in Trinity Bay, Texas, in response to projected sea level rise. The study combines numerical modeling and a geographic information system. A smoothing technique is used on a United States Geographical Survey (USGS) digital elevation model to obtain elevation profiles that more accurately represent the gently sloping wetlands surface. The numerical model estimates the expected elevation change by raster cell based on input parameters of predicted sea level rise, mineral and organic sedimentation rates, and sediment autocompaction rates. A GIS is used to display predicted elevation changes and changes in shoreline position as a result of four projected sea level rise scenarios over the next 100 years. Results demonstrate that this numerical model and methodology are promising as a technique of modeling predicted elevation change and shoreline migration in wetlands. The approach has potential utility in coastal management applications.

Understanding spatial perspectives on the spread and incidence of a disease is invaluable for public health planning and intervention. Choropleth maps are commonly used to provide an abstraction of disease risk across geographic space. These maps are derived from aggregated population counts that are known to be affected by the small numbers problem. Kernel density estimation methods account for this problem by producing risk estimates that are based on aggregations of approximately equal population sizes. However, the process of aggregation often combines data from areas with non-uniform spatial and population characteristics. This thesis presents a new method to aggregate space in ways that are sensitive to their underlying risk factors. Such maps will enable better public health practice and intervention by enhancing our ability to understand the spatial processes that result in disparate health outcomes.

Advocates of urban light rail transit argue that positive developments around station area(s) should offset the costs of implementing a transit system by creating more livable communities and enhance surrounding residential property values. In some cases, decreased urban landscape aesthetics have been reported. The purpose of this study is to contribute to this debate via an analysis of the impact of the Dallas Area Rapid Transit system on residential property values in Dallas County. By examining the impact of distance on property values of two features of the DART system: the transit station and the rail line, and by holding a series of structural variables constant, a net change in value can be calculated using a multi-regression model.

During the modern era, the urbanization of water has been facilitated by various privileged discourses, which valorize major engineering interventions for the sake of continued urban growth. This research examines discourse surrounding the 2-th Century proposal and construction of a reservoir near the then-tiny farming community of Grapevine, Texas, for the benefit of urban interests. I argue that urban interests produced Grapevine space as nothing more than a container for city water, by rendering meaningless any conception of space that was not directly articulated with urban economic networks. Modern discourse collapsed Denton Creek space from a watershed and landscape into a dimensionless node in the urban space of flows. In return, rural inhabitants were encouraged to progress and to modernize their own spaces: to become urban. Whereas urban discourse entails an implicit spatial imaginary of networks, I deploy the conceptual framework of settler colonialism to show that a core-periphery relationship remains relevant, and is not reducible to a network spatial ontology.

This analysis of faunal remains from eleven archaeological sites in the northern San Juan region, extensively occupied by the Ancestral Pueblo people until they leave the region by AD 1300, explores the effects of resource intensification of small wild and domestic resources leading up to this regional depopulation. By examining multiple lines of evidence, in addition to faunal abundance, causal factors are identified to address changes in abundances through time. In particular, age- and sex-based mortality are examined for lagomorphs (jackrabbits and cottontails) and domesticated turkey, respectively, to test hypotheses generated using the prey and patch choice models. Analyses of these resources follow a systematic paleontology which provides explicit identifications made of five sites from a large study area, Goodman Point Pueblo Unit. These data are integrated with those from large village sites from the encompassing central Mesa Verde region. The results of both analyses help clarify why the Ancestral Pueblo people left southwestern Colorado. During the final twenty-year occupation period, the results of this study support a shift from reliance on turkey husbandry to intense exploitation of locally available garden resources (i.e. cottontails).

In 1991, India adopted neoliberalism, a system of political economic practices that promotes private property and free trade, as its political and economic system to promote development in their country. India's neoliberal reform has created issues surrounding human development, resource accumulation, and power struggles. Eleven years later, in 2002, Bt cotton was introduced to the Indian agricultural sector. This research examines how the genetically modified organism Bt cotton is being used to commodify nature in the context of agriculture under neoliberalism. The research focuses on the dispossession of the rural farmers through the commodification of agriculture using Bt cotton. Dispossession of the rural farmers happen through the implications that arise from the commodification of nature. Through Marxist theory of primitive accumulation, this research analyzes accumulation by dispossession and how it neglects the working class and its struggle in rural India. Through this examination, the research will argue alternatives to the dispossession of the working class and the commodification of nature through Bt cotton. Dispossession, in this research, is examined both through working class, but also through the dispossession of biodiversity. Through the loss of biodiversity, the rural farmers are becoming dispossessed from a more sustainable environment. Along with these goals, …

This paper presents methods and results of county-level population estimation using Landsat Thematic Mapper (TM) images of Denton County and Collin County in Texas. Landsat TM images acquired in March 2000 were classified into residential and non-residential classes using maximum likelihood classification and knowledge-based classification methods. Accuracy assessment results from the classified image produced using knowledge-based classification and traditional supervised classification (maximum likelihood classification) methods suggest that knowledge-based classification is more effective than traditional supervised classification methods. Furthermore, using randomly selected samples of census block groups, ordinary least squares (OLS) and geographically weighted regression (GWR) models were created for total population estimation. The overall accuracy of the models is over 96% at the county level. The results also suggest that underestimation normally occurs in block groups with high population density, whereas overestimation occurs in block groups with low population density.

Rainfall interception is one mechanism by which tree canopies can reduce surface runoff in urban areas. The objectives of this research were to: 1) quantify rainfall interception by urban tree canopies, and 2) determine the influence of vegetation and microenvironmental factors on rainfall interception rates. In the city of Denton, Texas, 30 mature post oak (Quercus stellata) and blackjack oak (Quercus marilandica) trees were selected for study. Trees were assigned to one of three categories: clusters of trees on greenspace (CG), isolated trees on greenspace (IG), and isolated trees surrounded by pavement (IP). Throughfall (the volume of water that travels through the canopy and reaches the soil surface) collectors were placed beneath these trees and rainfall collectors were placed in nearby open areas. Throughfall and rainfall were collected daily from 19 March to 4 July. Interception was calculated as the difference between throughfall and gross rainfall. Over the study period, there were 27 days with measurable rainfall; daily rainfall ranged from 1-51 mm. Over the sampling period, rainfall interception for individual trees ranged from -10% to 49%, indicating high spatial variability in interception. Percent interception was highest for the CG treatment (22.7 ± 3.8 SE), intermediate for IG (27.4 ± …

The shopping center has held an important place in the American economy for decades. However, the concept has seen multiple revolution in terms of format. The most recent shopping center concept to gain rapid popularity is the lifestyle center – an outdoor shopping mall made to resemble a pleasant main street setting, with a tenant mix emphasizing dining and entertainment. In other words, the lifestyle center concept is geared toward selling consumers things to do, versus things to buy. This thesis studies the geography of lifestyle centers in the United States in both the large-scale and small-scale view. Results show that lifestyle centers are concentrated into larger urban areas, often with a population of over 1 million. An analysis of spatial agglomeration revealed that lifestyle centers are often several miles away from the nearest traditional mall, indicating that developers do not feel the need to build near established shopping districts where traditional malls lie. Finally, results concerning trade area characteristics show the characteristics of consumers in areas where lifestyle centers have been built. Findings in this study indicate that developers are utilizing a unique approach when selecting sites for lifestyle centers compared to traditional indoor malls.