Search Results

Analysis of Interrelationships between Climate Change and Cotton Yield in Texas High Plains
The Texas High Plains produces the most substantial amount of cotton in Texas. The region is a semi-arid area with limited precipitation, and it is, therefore, susceptible to climate change. Cotton production in the Texas High Plains is mostly dependent on irrigation to increase yield. The overall goal of this research was to study the interrelationships between climate change and cotton yield using correlation analysis and also to study how climate has changed in the region using trend analysis. A three-decade data (1987-2017) was analyzed to establish the relationship between climate change and cotton and also to determine how climate has changed in the area over the last 30 years. The research used precipitation and temperature data to assess climate change.The results of this research showed that annual mean temperature has lesser impacts on cotton yield, and the correlation between annual precipitation and cotton yield is insignificant. It also found out that high rates of temperature at the boll opening stage of cotton growth results in decreased cotton yield and that at the boll development and boll opening stages, precipitation is needed. Again, the research indicated that, on average, there had been a significant increase in temperature, but precipitation trends are insignificant. About 60% of cotton acreage in the area is irrigated. Therefore the research also found out that increasing trends of cotton yield may contribute to the decline of groundwater in the area.
Analyzing Tuberculosis Vulnerability and Variables in Tarrant County
Over 9 million new cases of tuberculosis (TB) were reported worldwide in 2013. While the TB rate is much lower in the US, its uneven distribution and associated explanatory variables require interrogation in order to determine effective strategies for intervention and control. However, paucity of case data at fine geographic scales precludes such research. This research, using zip code level data from 837 confirmed TB cases in Tarrant County obtained from Texas Department of State Health Services, explores and attempts to explain the spatial patterns of TB and related risk markers within a framework of place vulnerability. Readily available census data is then used to characterize the spatial variations in TB risk. The resulting model will enable estimations of the geographic differences in TB case variables using this readily available census data instead of time-consuming and expensive individual data collection.
App Stole My Gayborhood? A Transforming Ethos at the Intersection of Queer Urban Life and Cyberspace(s)
This thesis demonstrates a queer perspective stemming from a qualitative analysis of data gathered in interviews with LGBTQ+ people to analyze a transforming ethos of gayborhoods and queer desires. In particular, the research focuses on the interactive relationship between self-identified lesbian, gay, bisexual, transgender, and queer (LGBTQ+) participants; the cyberspace(s) of LGBTQ+ mobile-dating applications (apps); and tangible urban places. The topic of gayborhood demise and whether such places are worth saving has been debated by scholars and journalists for the last decade. The demise of gayborhoods is often thought to be a symptom of neoliberal urban processes such as gentrification within the context of the post-gay era and broader societal acceptance of homosexuality. This means the question of "if the gayborhood is worth saving" is inherently imbedded in an assumption that homosexuality is not viewed or treated as different or lesser than heterosexuality. In this imagined post-gay era, gayborhoods are declining because the dangers posed to the LGBTQ+ population are purported to no longer exist, so there is no longer a need for designated queer and/or safe places. This research destabilizes the assumptions embedded within the conception of the post-gay era by asking whether the gayborhood meets the needs and desires of contemporary queers. Alternatively, are LGBTQ+ mobile-dating apps part of gayborhood decline, and if so how? Therefore, the question of "if the gayborhood is worth saving" is not about assumed queer acceptance in greater society; rather, the question should be grounded in if the gayborhood fulfills the needs and desires of contemporary queers.
Assessing Agricultural and Hydrologic Potential of Ancestral Puebloan Community Centers using Open Source Data
The Pueblo III period marks a critical shift in settlement location of Ancestral Puebloan people within the Mesa Verde region. Community centers during the Pueblo I and Pueblo II periods were built on mesa tops, whereas canyon-rims and alcoves became the preferred settlement location during the Pueblo III period. Beginning in the Pueblo I period, community centers consisted of linear roomblock villages. By the late Pueblo II period great house community centers influenced by the Chaco culture system spanned the Mesa Verde region. The Pueblo III period hallmarks the transition to canyon-rim villages and cliff dwellings. The location of these Pueblo III centers is thought to be related to the need for a defensive position on the landscape, and access to water sources. This shift in settlement locations undoubtedly led to change in the access to resources, such as water, arable farmland, and wild food plants and game. This study aims to evaluate whether the change in community center location impacted the accessibility to arable farmland and water sources immediately available to Ancestral Puebloan people throughout time. Specifically, several variables related to farming potential and hydrologic potential, including soil type, soil moisture, elevation, cropland suitability, distance to water sources, drainage density, and hydrogeologic units were evaluated. Nine community centers within the McElmo drainage area in southwestern Colorado ranging in age from the Pueblo II to Pueblo III periods were included in this study.
Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas
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 ± 2.3 SE), and lowest for IP (9.1 ± 4.9 SE). Factors like wind exposure, wind-driven rain and overall tree health may help explain this variability. This research will contribute to our knowledge of hydrological fluxes in urban areas and the role of urban green infrastructure in stormwater runoff mitigation.
An Assessment of Riparian Buffer Effectiveness in the Upper Hickory Creek Watershed: A GIS Approach Using the Riparian Buffer Delineation Equation (RBDE) and the Buffer Improvement Potential Percentage (BP)
As population increases and urbanization occurs, watershed management will be critical in the protection of water resources in North Central Texas. By 2040, Denton County will nearly double its 2010 population. The Upper Hickory Creek Watershed lies west of Denton and empties into Lake Lewisville. Lake Lewisville provides drinking water for Denton, Dallas, and other neighboring cities. Mitigation of non-point source pollutants as a result of urban and agricultural practices is essential to protecting Lake Lewisville water resources. A common best management practice used to mitigate pollutants is the protection of riparian ecotones that occupy river corridors; however, recent agricultural and urban practices are diminishing these ecosystems and their services. In this paper, the riparian buffer delineation equation (RBDE) is used to assess the current state of Upper Hickory Creek Watershed to aid in the monitoring of the riparian buffers along stream corridors. While the RBDE was used as pre-assessment tool for the riparian buffer effectiveness in the watershed, a new form of the equation was used to evaluate riparian buffer improvement potential (BP) in conjunction with Denton County parcel data to provide insights into buffer effectiveness and identify areas for improvement on a landowner scale.
Automated Tree Crown Discrimination Using Three-Dimensional Shape Signatures Derived from LiDAR Point Clouds
Discrimination of different tree crowns based on their 3D shapes is essential for a wide range of forestry applications, and, due to its complexity, is a significant challenge. This study presents a modified 3D shape descriptor for the perception of different tree crown shapes in discrete-return LiDAR point clouds. The proposed methodology comprises of five main components, including definition of a local coordinate system, learning salient points, generation of simulated LiDAR point clouds with geometrical shapes, shape signature generation (from simulated LiDAR points as reference shape signature and actual LiDAR point clouds as evaluated shape signature), and finally, similarity assessment of shape signatures in order to extract the shape of a real tree. The first component represents a proposed strategy to define a local coordinate system relating to each tree to normalize 3D point clouds. In the second component, a learning approach is used to categorize all 3D point clouds into two ranks to identify interesting or salient points on each tree. The third component discusses generation of simulated LiDAR point clouds for two geometrical shapes, including a hemisphere and a half-ellipsoid. Then, the operator extracts 3D LiDAR point clouds of actual trees, either deciduous or evergreen. In the fourth component, a longitude-latitude transformation is applied to simulated and actual LiDAR point clouds to generate 3D shape signatures of tree crowns. A critical step is transformation of LiDAR points from their exact positions to their longitude and latitude positions using the longitude-latitude transformation, which is different from the geographic longitude and latitude coordinates, and labeled by their pre-assigned ranks. Then, natural neighbor interpolation converts the point maps to raster datasets. The generated shape signatures from simulated and actual LiDAR points are called reference and evaluated shape signatures, respectively. Lastly, the fifth component determines the similarity between evaluated and reference shape …
Behind the Curtain of Public Space: Revealing the Narratives of Corporate Street Hawking in Globalizing Accra
All street hawkers are not the same in many Newly Industrialized Countries (NICs) of the global south as often portrayed by the media and documented in extant literature. This perception has created a gap in knowledge as researchers explore street hawking activities in NICs. In this study, I investigated a new informality trend of street hawking is coming into being within the capital city of Accra, Ghana. As governance is increasingly becoming entrepreneurial, informal activities are gradually becoming formal. Formal and registered businesses are increasingly capitalizing on hawking activities to occupy public spaces. The advent of the informality trend, I term corporate street hawking opens up new issues for the political economy, labor, and urban studies. By employing semi-structured interviews with 47 street hawkers in Accra, this paper sought to investigate three broadly interrelated questions. First, how do neoliberal policies impact the production of public space in Accra? Second, is corporate street hawking a form of creative destruction? Finally, how do corporate street hawkers practice agency within Accra?
Big Game, Big Decisions, and Big Government: Understanding the Effects of Commodification on Deer and Feral Hog Hunting in Texas
My research examines how primary stakeholders interact with Texas' most harvested big game animals: white-tailed deer, which are increasingly impacted by chronic wasting disease (CWD), and feral hogs, which impact the landscape but effectively have no management strategy. Drawing on literature on wildlife governance in Texas, managing property and the commons, and disease landscapes, and broadly framed by themes of political and historical ecology, my research asks: (1) how do management goals for deer and feral hogs compare to hunting practices and hunting culture in Texas? (2) How are deer commodified by the Texas deer breeding industry? (3) How does the commodification of deer by breeders impact deer hunting practices in Texas? To examine how local stakeholders manage CWD and feral hogs, I conducted interviews among 21 stakeholders, including hunters, game wardens, game ranch managers, and deer breeders in Texas, as well as conducting participant observation at three deer conferences. Analysis shows that contrary to my expectations, not all participants viewed feral hogs negatively, with some viewing them as profit-making ventures. Inversely, how stakeholders contend with and understand CWD varies by a stakeholder's ability to generate profit from deer breeding. Furthermore, the majority of participants identified deer breeding operations as the greatest risk for spreading CWD; deer-breeders themselves, not surprisingly, perceived CWD as either low risk or a big government conspiracy. This research demonstrates a need for further regulation or outlawing deer breeding altogether.
Building a Digital Twin of the University of North Texas Using LiDAR and GIS Data
Digital twins are virtual renditions of the actual world that include real-world assets, connections, activities, and processes. Recent developments in technologies play a key role in advancing the digital twin concept in urban planning, designing, and monitoring. Moreover, the latest developments in remote sensing technology have resulted in accurate city-scale light detection and ranging (LiDAR) data, which can be used to represent urban objects (buildings, vegetation, roads, and utilities), enabling the creation of digital twin of urban landscapes. This study aims to build a digital twin of the University of North Texas (UNT) using LiDAR and GIS data. In this research, LiDAR point clouds are used to create 3D building and vegetation modeling along with other GIS data (bicycle racks and parking areas) in creating a digital twin model. 3D Basemap solutions of ArcGIS Pro and ArcGIS Online Scene Viewer, respectively, are used to create an initial 3D urban model and build the ultimate digital twin of UNT. The emergency management floorplans of UNT buildings are incorporated into the digital twin to increase emergency management efficiency. Moreover, solar power potential for individual buildings at UNT has been estimated using the Digital Surface Model (DSM) and integrated into the digital twin model to identify the buildings with the highest solar energy capacity. This study indicates that implementing a digital twin in a university enhances campus efficiency, safety, and sustainability, serving as a central system for a smart campus and contributing to intelligent urban growth.
Climate Injustice and Commodification of Lives and Livelihoods in Southwest Coastal Bangladesh
Just and equitable responses to the disparate impacts of climate change on communities and individuals throughout the world are at the heart of the concept of climate justice. Commodification, in the context of my research, is the process of monetizing nature and livelihoods for the purpose of surplus accumulation and profit maximization. In this study, my aim was to contextualize the concepts of climate injustice, disaster capitalism, and the commodification of lives and livelihoods in the specific setting of disaster vulnerability in southwest coastal Bangladesh. By conducting a case study in Kamarkhola and Sutarkhali regions of southwest coastal Bangladesh, I utilized discourse analysis and content analysis of livelihood interviews, semi-structured interviews, and policy documents to demonstrate the conceptual interrelation among global climate change, climate injustice, disaster capitalism, and capitalist expansion in environmentally precarious areas. I argue that in Southwest Coastal Bangladesh, the vulnerability to disasters stems from a complex and multifaceted layer of social hierarchies and inequalities, entwined with factors such as class and power relations. I also argue that Inequalities in the political, economic, and social realms have a key role in imposing vulnerability on disadvantaged people living in ecologically vulnerable areas. The perpetuation of inequality is sustained by the expansion and accumulation of capital through the dispossession and exploitation of natural resources. The existing approaches to climate change adaptation in the southwest coastal region of Bangladesh are deeply entrenched in neoliberal capitalism. The introduction of neoliberal economic policies, such as the privatization of state lands and the promotion of export-oriented aquaculture, created favorable conditions for capitalist expansion in environmentally vulnerable places through "accumulation by dispossession."
Crisis, New Imperialisms, and Accumulation by Dispossession: The Case of the Pakistan Railways
My research examines the three interrelated concepts of crisis; new imperialisms, spatial-temporal fix and accumulation by dispossession (ABD) stemming from the work of David Harvey as a way to understand the contested history of the Pakistan Railways. For the first thirty odd years after Pakistan's inception in 1947, the railways, a state-owned institution, was the primary mode of transport for the public, cargo, and workers. Alongside basic infrastructure, the railways had a vast network of hospitals, schools, workers' colonies and an array of physical infrastructure connected to production, operations and other aspects of the economy. The systematic ransack and decline of the Pakistan Railways reached its peak in 2010. Despite several attempts throughout the 1990s by successive democratic and military-led governments backed by the IMF/World Bank in 2015, it was announced that Pakistan railways would be revived under the banner of the 46 billion dollar China Pakistan Economic Corridor (CPEC) as part of the changing geopolitical context of growing regional connectivity and new Chinese imperialism. By examining the processes that underlie ABD, such as spatial-temporal fix, the following research shows that these processes not only reflect a shift of resources away from the public domain, but in Pakistan also entailed the transformation of the railways from a utilitarian welfare organization to an entity that facilitates looting, unbundling, and dispossession of shared resources and infrastructure.
The Death and Life of Great American Malls: (Un)Spectacular Creative Destructions, Luxury Mixed-Use Developments, and Gentrification in Dallas-Fort Worth
Mall after mall was built in American cities, exhaustively emulated by developers often working in concert with civic governments. In service of capital, neoliberal urban governance engages in the risky subsidization of spatio-spectacle production, working together with private business entities to bolster tax revenue and aid in private capital accumulation. The extensive replication of malls in close geographic proximity to one another across the American landscape, erected through the neoliberal partnerships of civic governments and private business interests, has greatly contributed to mall decline and mall death. There is now, however, a new spatio-spectacle that has arisen to take the place of the "great American shopping mall"—the luxury mixed-use development. These luxury mixed-use projects have been adopted as a new trend within urban development following the reality of sweeping mall decline and are proliferating across the (sub)urban landscape. Luxury mixed-use developments, I argue, are merely a continuation of late capitalism's problematic spectacle fetish. Moreover, this process is revealed to be inextricably entangled with gentrification, driven by cities' neoliberal desires to become/maintain status as global, "world-class" cities, performed through the spatialized ideology of neoliberal multiculturalism.
Developing a Soil Moisture-Based Irrigation Scheduling Tool (SMIST) Using Web-GIS Technology
Software as a service (SaaS) is a primary working pattern and a significant application model for next generation Internet application. Web GIS services are the new generation of the Software as a service that can provide the hosted spatial data and GIS functionalities to the practical customized applications. This study focused on developing a webGIS based application, Soil Moisture-Based Irrigation Scheduling Tool (SMIST), for predicting soil moisture in the next seven days using the soil moisture diagnostic equation (SMDE) and the upcoming seven precipitation forecasts made by the National Weather Service (NWS), and ultimately producing an accurate irrigation schedule based on the predicted soil moisture. The SMIST is expected to be capable of improving the irrigation efficiency to protect groundwater resources in the Texas High Plains and reducing the cost of energy for pumping groundwater for irrigation, as an essential public concern in this area. The SMIST comprised an integration of web-based programs, a Hydrometeorological model, GIS, and geodatabase. It integrates two main web systems, the soil moisture estimating web application for irrigation scheduling based on the soil moisture diagnostic equation (SMDE), and an agricultural field delineation webGIS application to prepare input data and the model parameters. The SMIST takes advantage of the latest historical and forecasted precipitation data to predict soil moisture in the user-specified agricultural field(s). In this regard, the next seven days soil moisture versus the soil moisture threshold for normal growth would be presented in the result page of the SMIST to help users to adjust irrigation rate and sequence.
Effect of Barrier Height on Magnitude and Character of Hurricane Harvey Washover Fans, Matagorda Peninsula, Texas
This study uses topographic profiles, washover fan volumes, and shoreline retreat rates to explore relationships between barrier types and Hurricane Harvey storm washover sedimentation. Pre- and post-Hurricane Harvey topographic profiles were created on 15 transects using Bare Earth LiDAR (2016) and surveyed elevations (2019). Depth and area of washover fan measurements were collected to estimate washover fan volumes. An inverse relationship was found between washover fan volume and pre- and post-storm barrier heights. Based on the topographic profiles, one section of shoreline had a scarp up to 3m high which blocked overwash, but appears to have increased shoreline erosion. In contrast, a low-lying section of shoreline generated relatively large washover fans, but experienced less shoreline retreat. Shoreline retreat was further quantified between 2014 and 2019 using Google Earth Imagery from 2014, 2016, 2017, and 2019 to track migration of the shoreline. The entire shoreline in the study area is undergoing relatively rapid retreat, but the results suggest that Hurricane Harvey increased erosional rates. The Colorado River Jetty borders the study area and may have acted as an anthropogenic barrier, likely reducing storm surge energy and contributing to marsh aggradation on transects in its close proximity. The study findings indicate that the identification and incorporation of other variables that influence washover magnitude would further the understanding of this complex natural system. The research results provide valuable information on the interaction of hurricane storm surge with natural and anthropogenic barriers, beach and dune erosion, and marsh aggradation along the coast of Texas.
The Geography of Partial-Market Exits: Applying Geospatial and Econometric Methods to Analyze 2017 Department Store Closures in the United States
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 probability of closure.
The Geography of Retail Clinics Post Implementation of the Affordable Care Act
Retail clinics are walk-in clinics designed for convenience and for servicing minor health issues and certain acute conditions. The model began as a way of bringing both convenience and care to areas that have lower levels of access to primary care resources. With the implementation of Affordable Care Act (ACA) in March 2010, populations that were previously uninsured were now required to have access to some level of health insurance. These populations presented a potential new market for retail clinics. This research shows that post implementation of the ACA, retail clinics tend to locate in areas with higher incomes and, generally, greater access to primary care.
GIS-Based Analysis of Local Climate Zones in Denton, Texas
This study implemented a GIS-based analysis of local climate zones (LCZ) in Denton, TX with data sets from 2009, 2011, 2015, and 2016. The LCZ scheme enables evaluation of distinct regions' thermal characteristics with greater granularity than conventional urban-rural dichotomies. Further, the GIS-based approach to LCZ mapping allows use of high-resolution lidar data, the availability of which for the study area enabled estimation of geometric and surface cover parameters: height of roughness elements, sky-view factor, and building surface fraction. Pervious surface fraction was estimated from National Landcover Database impervious imagery. A regular grid was used to estimate per-cell mean values for each parameter, and with a decision-making algorithm (if/then statements) two maps were produced (2011 and 2015) and six LCZ identified in each: LCZ 6 (open low-rise), LCZ 8 (large low-rise), LCZ 9 (sparsely built), LCZ A (dense trees), LCZ B (scattered trees), and LCZ C (bush/scrub). Post-processing was carried out to ensure identified zones met the spatial minimum for qualification as LCZ. Landsat Collection 2 Level 2 surface temperature products from various seasons of 2011 and 2015 were acquired to examine LCZ thermal differentiability, and preliminary surface urban heat island intensity values were estimated. Particular attention was afforded to issues regarding data quality and classifier threshold adjustment.
Global Techno-Capitalism and the Production of Hate: Understanding Political-Economic and Ideological Utility on YouTube and Gab
The production of Hate, albeit a historical, long-existing, and relentless process, has been reinvigorated by the simultaneously globalizing and localizing power of cyberspace. Techno-capitalism, often perceived as the actuating force of neoliberal globalization, has emanated novel formations of social interaction, community formation, the dissemination of ideology, and political mobilization. Far-right ideology is being globalized throughout popular social cyberspaces like YouTube by thought leaders or ideological entrepreneurs, while users then localize within alternative social cyberspaces like Gab, wherein their beliefs are reaffirmed, identities are consolidated, and communities are formed. This process is integral to the materialization of far-right extremism, manifested as political action in real, physical space, and thus, illuminates new expressions of real virtuality, various politics of scale, and contemporary consequences of neoliberal globalization.
Green Entrepreneurialism and the Making of the Trinity River Corridor: The Intersection of Nature and Capital in Dallas, Texas
Since the adoption of neoliberalism, many cities have taken to integrating nature with capital accumulation to create a sense of place. This has been closely tied to urban greening, or green "revitalization." As part of curating this desired character, city governments are working to roll out plans to restore and renew neighborhoods using their natural landscapes through methods such as reforestation, the creation of parks, and commercial development. These cities, deemed Entrepreneurial cities, are increasingly incorporating natural or green spaces into their development of character as part of their branding schemes. This research focuses on the role of nature as the site of economic development and community revitalization within Dallas, Texas. This research examines how the City of Dallas uses nature to attract capital, and how the narratives of development relate to residents' visions for development in the historically neglected Joppa neighborhood in the Trinity River Corridor. Development near Joppa could be an example of how the natural landscape is being used to not only attract developers but also to bring a different ‘class' of resident into the area. By exploring this intersection of nature and capital in Dallas, we can better understand the nuanced ways through which the neoliberalization of nature can lead to deeper social and economic disparities.
How Receiving Communities Structure Refugee Settlement Experiences: The Case of Burmese Immigrants in DFW
The Dallas-Forth Worth Metroplex (DFW) serves as a diverse resettlement location for globally displaced refugees. While research examines how the nation impacts refugee resettlement, studies that examine the role of the city and community in placemaking are still lacking. In city resettlement investigations, research often focuses broadly on advocacy and political movements rather than the impacts of local-level structures and policies. In this paper, I develop an evaluation model using Jenny Phillimore's categories for successful refugee resettlement that examines how structural barriers, community interactions, and resource accessibility affect space and place for refugee populations. Through an ethnography of Chin and Rohingya refugee communities in DFW, I explore the differences between community-settled and state-settled refugee groups and the idea of an integrated resettlement program. Additionally, I argue that refugees who choose their settlement location in the United States are empowered and thus have a stronger connection to their host community than state-settled refugees. For example, in interviews, the Chin emphasized their ownership of Lewisville and feelings of home, while the Rohingya expressed feelings of placelessness and dispossession in Dallas. As governments push towards an entirely privatized system of refugee resettlement, this research argues for an integrated method that draws upon federal resources and community connections. Through the experiences of Lewisville's Chin community, this research demonstrates the potential of such a program in the United States.
Hurricane Harvey and the Devastation of Dispossession
Disaster science is a procedural field often construed as producing blanket policies that attempt to cover everyone, but the complexity of human lived experiences must have a space to exist within disaster science if its research and findings are to be effective. This thesis illustrates that disaster policies and publications often leave out the most vulnerable communities—those in greatest need of collective support. Through critically analyzing beautification through green space, discussing photovoice interviews, and by deconstructing public preparedness documents published by Harris County Office of Homeland Security and Emergency Management (HCOHSEM), it is clear that accumulation by dispossession filters down through not only property and money but also access to green spaces and a healthy life. By dispossessing low-income communities of their right to green spaces and life, those communities end up in places that are environmentally dangerous, leaving them at a disadvantage in the disaster preparedness and recovery process. This thesis serves as a case study highlighting how HCOHSEM failed to provide low-income communities with assistance prior to, during, and after Hurricane Harvey. The lessons from these gaps in protective measures show that public policies need to be malleable to ensure residents of any community are covered. Though no two communities are alike, other cities and federal emergency entities can learn about what public policy measures require progressive changes to better serve the most vulnerable communities.
Improvement of the Soil Moisture Diagnostic Equation for Estimating Root-Zone Soil Moisture
Soil moisture information can be used accurately in determining the timing and amount of irrigation applied to plants. Pan and Pan et al. proposed a robust and simple daily diagnostic equation for estimating daily soil moisture. The diagnostic equation evaluates the relationship between the soil moisture loss function and the summation weighted average of precipitation. The loss function uses the sinusoidal wave function which employs day of the year (DOY) to evaluate the seasonal variation in soil moisture loss for a given year. This was incorporated into the daily diagnostic equation to estimate the daily soil moisture for a location. Solar radiation is an energy source that drives the energy and water exchanges between vegetation and the atmosphere (i.e., evapotranspiration), and thus impacts the soil moisture dry-down. In this paper, two parameters (the actual solar radiation and the clear sky solar radiation) are introduced into loss function coefficient to improve the estimation of soil moisture. After the Introduction of the solar radiation data into soil moisture loss function, a slight improvement was observed in the estimated daily soil moisture. Pan observed that generally the correlation coefficient between the estimated and the observed soil moisture is above 0.75 and the root mean square error is below 5.0 (%v/v). The introduction solar radiation data (i.e. clear sky solar radiation and actual solar) improve the correlation coefficient average for all the sites evaluated by 0.03 when the root mean square error is generally below 4.5(%v/v) for the entire root zone.
Lithic Production at the Mesilla Phase Placitas Arroyo Site Complex Doña Ana County, New Mexico
This study of lithic analysis shifts attention from typological studies to explicitly behavioral analyses, complimenting studies of both intrasite and intersite patterns of variability and change. Analysis of several assemblages from the Placitas Arroyo site complex reveals changing patterns of raw material procurement and selection, core reduction strategies, as well as tool production and discard. The most striking result thus far is the quite uniform emphasis on flake production from well-prepared cores, and the near absence of manufacture or maintenance of bifacial tools, especially projectile points. Associated with common ground stone artifacts, the flaked stone materials may well represent intensive food processing. Regardless, the technological patterns being revealed by this approach illustrate a productive new means to gain insights into changing behaviors in the Jornada Mogollon cultural tradition.
Location Analysis of Lifestyle Centers: Uncovering Patterns and Potential Driving Factors behind Site Selection
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.
Memory and Continuity Amidst Irreversible Decline in the Texas Big Empty
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.
A Multi-Proxy Approach to Identifying Marine Overwash Sedimentation and Terrestrial Flood Sedimentation in a Coastal Lake in Southeastern Texas
This research project focuses on using a multiproxy approach to discriminate between overwash and non-hurricane marsh sediments within the bed of a coastal lake. 3 marsh cores were collected in an area of McFaddin National Wildlife Refuge just south of Clam Lake that are known to contain 4 hurricane overwash deposits, Ike, Rita, Carla, and Audrey. LOI and XRF analysis were used to determine the signature of the hurricane overwash layers. 3 more cores were collected from Clam Lake where there are no visible sand layers. The elemental signature of the overwash layers found in the marsh cores was used to run a hierarchical cluster analysis on the lake cores. This was able to determine the effectiveness of XRF's ability to distinguish between hurricane overwash and marsh sediments. The combination of cluster analysis, LOI, and XRF can tentatively identify hurricane overwash deposits in a coastal lake, however, it is more successful in the marsh cores. Results in the lake cores are somewhat inconsistent and uncertain, possibly because there may have not been enough overwash deposits to identity or that the XRF analysis needs more distinct sand layers to distinguish between overwash and marsh.
Particulate Matter Accumulation to Urban Rock Pigeon (Columba livia) Feathers
This research investigates particulate matter (PM) deposition to rock pigeons (Columba livia) in urban environments within Denton County, Texas. Pigeon habitat was characterized within a 2-km radius at eight locations using the 2016 National Land Cover Database (NLCD). In summer 2020, feathers were sampled from 10 rock pigeons at two locations (n = 20) differing in degree of urban development. Birds were captured using walk-in funnel traps baited with bird seed. Based on molt pattern and appearance, four old flight feathers were identified and sampled from each bird. New primary feathers were obtained from each population as reference samples. Feathers were washed three times with double deionized water and acetone, and the solution vacuum filtered through a glass microfiber filter to collect all particles >1.5 µm in diameter. Particulate matter mass was determined by gravimetric analysis and calculated per unit feather surface area. Relative PM accumulation rates were significantly different between the populations. Characteristics of urban land cover, proximity to and types of emissions sources, wind exposure, and building density were drivers of variability in PM deposition to feather surfaces. The results from this study should be useful for subsequent research to help identify best practices for using feathers collected from pigeons or other urban restricted bird species to monitor PM levels across multiple spatial scales.
Photoinduced Toxicity in Early Lifestage Fiddler Crab (Uca longisignalis) Following Exposure to Deepwater Horizon Spill Oil
The 2010 Deepwater Horizon (DWH) oil spill resulted in a large release of polycyclic aromatic hydrocarbons (PAH) into the Gulf of Mexico. PAH can interact with ultraviolet radiation (UV) resulting in increased toxicity, particularly to early lifestage organisms. The goal of this research was to determine the sensitivity of fiddler crab larvae (Uca longisignalis) to photo-induced toxicity following exposure to Deepwater Horizon spill oil in support of the DWH Natural Resource Damage Assessment. Five replicate dishes each containing 20 larvae, were exposed to one of three UV treatments (10%, 50%, and 100% ambient natural sunlight) and one of five dilutions of water accommodated fractions of two naturally weathered source oils. A dose dependent effect of PAH and UV on larval mortality was observed. Mortality was markedly higher in PAH treatments that included co-exposure to more intense UV light. PAH treatments under low intensity sunlight had relatively high survival. These data demonstrate the importance of considering combined effects of non-chemical (i.e. UV exposure) and chemical stressors and the potential for photo-induced effects after exposure to PAH following the Deepwater Horizon spill.
The Political Economy of Retailing Sustainable Food: Green Consumerism and Sustainability
In recent decades, the global impacts of unsustainable consumption and production patterns have become a leading topic of sustainability, and more recently, climate action discourse. At the policy level, green consumerism – an element of green capitalism – has been positioned as the pathway to more sustainable consumption and production (SCP) practices. Within this model, eco-labeling schemes are used to communicate various sustainability attributes, or conditions of production, to the consumer. This study set out to investigate whether SCP is achievable through green consumerism using a two-part case study that centers around the egg industry and specific hen welfare standards. The case study examines the effectiveness of egg eco-labeling schemes and related statements and images placed on egg packaging in informing consumers' purchasing decisions. It also examines the impacts of green consumerism on organic egg production in the presence of strong consumer demand for enhanced hen welfare standards. The results of the case study demonstrate that in the egg industry, green consumerism is not highly effective because consumers' purchasing decisions are often informed by vague and misleading information about conditions of production. Moreover, the presence of strong consumer demand has not resulted in enhanced hen welfare standards in organic production. In interpreting these findings through the lens of David Harvey's theory of the spatial fix, I argue that the true role of green consumerism is to facilitate a spatial fix to resolve the chronic crisis of overaccumulation in the conventional egg industry. Furthermore, that the limitations and contradictions within green consumerism (e.g. vague or insignificant eco-label claims) aid in removing the barrier of capital fixity so that the spatial fix can occur.
Public Market Trade Areas: Local Goods, Farmers, and Community in the U.S. Southwest Region, 1996-2016
The number of public markets in the United States increased from more than 300 in the 1970s to more than 8,600 by 2016. This increase in markets is related to changes in food production, localism and the local food systems movement, socioeconomic changes, cultural changes, and perceptions of embeddedness. Research on the underlying conditions for the success of public markets is scant in the United States, and especially in the USDA Southwest Region. This study provides analysis of public market locations as compared with non-market locations by drive-time trade areas during a 20-year period, 1996 and 2016, to gain further insights into factors leading to their success. The results from logit regression analyses and simulations of socioeconomic, college-town status, and climate-grid classifications find an increased likelihood of public markets with population, education, college town status, and some climate-grid locations. Median income, surprisingly, has an inverse relationship with public market success. Qualitative data and a literature review point to three types of embeddedness that motivate customers to attend public markets. This study concludes that "local nontradable consumer goods" tied to place are offered at these "nontradable consumption amenities." These amenities are "third places" that promote social interaction and become important places of community, farmer support, and commerce across the Southwest Region.
Quantification of the Seasonality and Vertical Dispersion Environment of PM2.5 Variation: A Comparative Analysis of Micro-Scale Wind-Based Buffer Methods
Increasing PM2.5 (particulate matter smaller than 2.5 micrometers) poses a significant health risk to people. Understanding variables critical to PM2.5 spatial and temporal variation is a first step towards protecting vulnerable populations from exposure. Previous studies investigate variables responsible for PM2.5 variation but have a limited temporal span. Moreover, although land-use classes are often taken into account, the vertical environment's influence (e.g., buildings, trees) on PM2.5 concentrations is often ignored and on-road circle buffers are used. To understand variables most critical to PM2.5 concentration variation, an air pollution sensor and GPS unit were affixed to a bicycle to sample for variables over three seasons (spring, summer, fall). Samples were taken on a route during the weekdays at four targeted hours (7AM, 11AM, 3PM, and 7PM) and joined with meteorological data. 3D morphology was assessed using LiDAR data and novel wind-based buffers. Wind speed only, wind direction only, and wind speed and direction buffers were computed and compared for their performance at capturing micro-scale urban morphological variables. Zonal statistics were used to compute morphological indicators under different wind assumptions in seasonal ordinary least squares regression models. A comprehensive wind and buffer performance analysis compares statistical significance for spatial and temporal variation of PM2.5. This study identifies the best wind parameters to use for wind-based buffer generation of urban morphology, which is expected to have implications for buffer design in future studies. Additionally, significant exposure hotspots for UNT students to PM2.5 pollution are identified.
Reconstructing Identity with Urban Community Agriculture: How Refugees Confront Displacement, Food Insecurity, and Othering through Community Farming
Ethnic and religious conflict, and the deepening of capitalism have led to global diaspora at unprecedented levels. The United Nations High Commissioner for Refugees reported that as of 2015, 1 in every 122 persons worldwide were either a refugee, internally displaced, or seeking asylum. The U.S. currently admits the largest number of refugees worldwide. However, policies fail to reflect the multitude of elements that constitute successful resettlement. Moreover, many refugees come from farming backgrounds and are forced to migrate to a landless urban environment, where their skill sets may not be utilized and farm land is not available. I argue that existing resettlement processes are embedded in logics and practices that alienate humans from nature and from each other through competition, isolation, and placeless environments. Through an exploration in concepts of urban agriculture, place-making, identity, and otherness, and illuminating the experiences of resettled refugees involved in a community gardening project in Fort Worth, Texas, show how the urban refugee garden provides the individual a space to narrate an identity, and to resist industrial agriculture and labor outside their industry. Exploring best practices in resettlement should be a priority to governments, politicians, and communities involved in the process and highlight the reasons to advocate these types of resettlement alternatives.
Redesigning Police Beat Zone Placement to Improve 911 Response Time: A Data Driven Approach
Research suggests that using data driven solutions in policing strategies improves the quality of service provided by the police department. Unfortunately, many police departments, including the Denton Police Department, do not use their spatial data to inform beat zone placement. Analysis of the current beat zone configuration found that there are disparities in the workload, as measured by number of calls for service, between beat zones. Further, there was also a statistically significant difference between the median response times across all the five beat zones in Denton. This means that the median response time varies depending on where the call for service originates. Using readily available data, these police departments can apply methods such as UPAS to improve the quality of service provided by the department. UPAS is a deterministic algorithm that produces a given number of contiguous spatial partitions of approximately equal population size; in this case, calls for service are substituted for population. Although this algorithm was originally developed to create solutions for bio-terrorism response planning, it has been applied to the problem of creating beat zones of roughly equal workload in this research. I have shown that this algorithm results in a beat zone configuration that significantly reduces the difference in workload between the busiest and least busy beat zone (~94% reduction). Assuming an equal distribution of resources across beat zones, having approximately similar workloads should lead to fewer disparities in quality of service.
Renewable Electricity in DFW: Access, Distribution, and Consumer Awareness
Texas is the leading producer of renewable energy in the U.S, and Dallas-Fort Worth (DFW) is the largest metropolitan area in the state. Texas has a deregulated energy market, with three types of providers: privatized, public-owned, and co-operatives. Privatized providers compete in the deregulated market, and consumers choose between hundreds of electricity retailers. Public-owned providers are owned by the municipality, and electricity consumers that live within the city limits must use the municipal provider. Electric co-operatives operate similarly where customers within the region must use the co-operative, but instead of being owned by the city, co-ops are owned by the members (customers). To date, the availability, cost, accessibility, and outreach of renewable electricity among these provider types remains unclear. For this reason, my research examines the renewable energy market in DFW by asking: (1) Who has access to renewable energy and how do they understand it? (2) How do electricity retailers distribute and make renewable energy available? and (3) If consumers can choose their provider, why do they select certain electricity plans over others? My findings suggest that while many consumers want or are open to using renewable energy, uncertainties surrounding how to find or choose a provider, price, and lack of information about renewables are obstacles for consumers to access renewable energy. Additionally, while renewable energy is widely distributed in the region, there are disparities in renewable energy options.
Retail District Evolution: An Exploration of Retail Structure and Diversity, a Case Study in Denton, Texas
It is well established that national retail chains impact small, single location retail businesses in terms of revenue generation, retail structure, retail type diversity, and location. This study examines the retail structure and diversity of five retail districts in the City of Denton, Texas. The analysis focuses on one central business district (CBD), one traditional retail strip center (University Drive, also known as US HWY 380), one special retail district (Fry Street District), one traditional enclosed shopping mall and associated development (Golden Triangle Mall), and one power retail center (Denton Crossing). The empirical foundation for the investigation is a historical business database covering years 1997 to 2010, obtained from Info Group's Reference USA. This Reference USA database includes location, industry, and status (single versus chain location) information for each business. Retail diversity and evenness were measured for each of the five retail districts using the Simpson's Diversity Index and the Simpsons Measure of Evenness, leading to specification of the differences that exist in retail structure and diversity among the districts. Golden Triangle Mall and Denton Crossing were primarily chain location in composition while Fry Street District, the CBD, and University Drive were primarily single location in composition. Across all years, the single versus chain status of the local business communities did not substantially change within any of the districts. The Fry Street District exhibited the most change in diversity as well as the lowest overall diversity among the retail districts, followed by University Drive and Golden Triangle Mall. The CBD did not experience any major change in retail type diversity. However, all retail districts experienced major changes in retail evenness. Overall for the city, single location retail businesses accounted for the majority of all the retail businesses, however, chain locations employed more people. In total, these findings indicate that the …
Seeds of Disempowerment: Bt cotton and Accumulation by Dispossession in the States of Maharashtra, Telangana, and Andhra Pradesh in India
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, the research will also incorporate themes of food security through changing landscape of agriculture due to the incorporation of Bt cotton. This research argues the contradictions that are presented through the commodification of agriculture under neoliberalism and provide a contribution to social justice literature, and our understanding of the relationship between technology and the commodification of nature.
Social Vulnerability and Bio-Emergency Planning: Identifying and Locating At-Risk Individuals
In 2006, the United States Congress passed the Pandemic All-Hazards Preparedness Act (PAHPA) which mandated that all emergency preparedness planning shall address at-risk populations. Further, in 2013, the reauthorization of this act, known as PAHPRA, defined at-risk individuals as "children, older adults, pregnant women, and individuals who may need additional response assistance." This vague definition leaves emergency managers, planners, and public health officials with the difficult task of understanding what it means to be at-risk. Further, once identified, the geographic location of at-risk individuals must be obtained. This research first uses the concept of social vulnerability to enhance the understanding of what it means to be "at-risk." Then, by comparing two data disaggregation techniques, areal weighted interpolation and dasymetric mapping, I demonstrate how error of estimation is affected by different scenarios of population distribution and service area overlap. The results extend an existing framework of vulnerability by stratifying factors into quantifiable and subjective types. Also, dasymetric mapping was shown to be a superior technique of data disaggregation compared to areal weighted interpolation. However, the difference in error estimates is low, 5 percent or less in 72 percent of the test cases. Only through local collaboration with community entities can emergency planners access the appropriate data to both: 1) understand the nature of at-risk individuals in their service areas and 2) spatially target resources needed to ensure all individuals are planned for in case of a bio-emergency.
Soil Carbon Accumulation in an Urban Ecosystem: Canopy Cover and Management Effects
Black carbon (BC), a stable form of organic carbon (OC), is a byproduct of the incomplete combustion of biomass, biofuels, and fossil fuel. The main objectives of this research are to examine the spatial distribution of OC and BC in urban soil and determine the influence of tree canopy cover and landscape maintenance on soil carbon accumulation. Soil sampling was conducted at 29 sites throughout the City of Denton, Texas, in May 2019. Samples were collected from underneath post oak canopies and in adjacent open areas and were analyzed for total carbon (TC), total organic carbon (TOC), total N (TN), C:N ratio, and BC. Although maintenance levels had no significant effect, TOC was greater underneath trees (5.47%, 5.30 kg/m2) than lawns (3.58%, 4.84 kg/m2) at the surface 0-10 cm. Total nitrogen concentration was also greater underneath trees (0.43%) than lawns (0.31%) at the surface 0-10 cm. Preliminary results for BC were closely correlated to TOC. The lack of difference in C:N ratio between cover types indicates that leaf litter quality may not be the primary driving factor in soil C and N accumulation. Instead, differences in soil properties may be best explained by manual C inputs and greater atmospheric deposition of C and N to soils with tree canopy cover. Identifying patterns and potential drivers of soil OC and BC accumulation is important because soil carbon sequestration not only reduces atmospheric CO2, but also may provide additional pollution mitigation benefits, thereby contributing to a more sustainable urban environment.
A Spatial Decision Support System to Dynamically Compute and Map Neighborhood Indices
Neighborhoods are organic entities that are in a state of constant change and are driven by the specific context of the problem being investigated. The subsequent lack of consensus on a universal geographic definition for what constitutes a neighborhood can lead to biased interpretations of relationships between human activities and place. Further, while existing geographical information system software allows users to combine a range of geographic objects to generate regional units of analyses, their design does not explicitly assess how changing patterns, such as populations, impact the data expressed within them. This research develops an exploratory geographical information system framework that allows users to dynamically delineate neighborhoods based on user-specified characteristics. These include socioeconomic and similar measurements of neighborhood classification from information obtained from secondary data sources, including parcel data, land use/land cover information, and attribute data provided by the United States Postal Service. The proposed methodology creates custom geographies from readily available tract data obtained from various federal and state data repositories to produce indices. By allowing the user to dynamically weigh the combinations of variables used to define their neighborhood, this thesis introduces a solution to a common analytical problem in the discipline.
Spatial-Temporal Assessment of Irrigation Application Changes and Soil Moisture Analysis Using SMAP Maps
Due to inadequate long-term and large-scale observation approach for observation of soil moisture across the globe, this study intends to unveil the importance of using simulated soil moisture fields from land surface models, forced with observed precipitation and near-surface meteorology in monitoring drought and formulating effective water management practices for continued production irrigation applications. This study shows that socio-economic and ecosystem effects can be determined by evaluating spatial-temporal changes in irrigation applications. Thus, it facilitates understanding of the importance of water management and how water, energy, and carbon flows protect our climate and environment. By using Soil Moisture Active Passive (SMAP) in monitoring soil moisture, the information obtained is critical in providing early drought warnings, particularly in those parts of the United States that experience flash agricultural droughts. Further, this study highlights that frequent and reliable soil moisture measurements from SMAP helped improve the predictive capability of weather and climate models.
Urban Trees as Sinks for Soot: Deposition of Atmospheric Elemental Carbon to Oak Canopies and Litterfall Flux to Soil
Elemental carbon (EC), a product of incomplete combustion of fossil fuels and biomass, contributes to climate warming and poor air quality. In urban areas, diesel fuel trucks are the main source of EC emissions from mobile sources. After emission, EC is deposited to receptor surfaces via two main pathways: precipitation (wet deposition) and directly as particles (dry deposition). Urban trees may play an important role in removing EC from the atmosphere by intercepting and delivering it directly to the soil. The goal of this research was to quantify the magnitude of EC retention in leaf waxes (in-wax EC) and EC fluxes to the soil via leaf litterfall in the City of Denton, Texas. Denton is a rapidly growing urban location in the Dallas-Fort Worth metropolitan area. A foliar extraction technique was used to determine EC retention in leaf waxes. Foliar samples were collected monthly, from April through July, from pairs of Quercus stellata (post oak, n=10) and Quercus virginiana (live oak, n = 10) trees. Samples were rinsed with water and chloroform in a two-step process to determine EC retained in leaf waxes. A Sunset OC/EC aerosol analyzer was utilized to analyze the EC content of extracts filtered onto quartz-fiber filters. From April through July, leaf litter was collected bi-weekly under 35 trees (20 post oak, 15 live oak), and oven dried to determine dry weight. EC retained by tree canopies was estimated by multiplying in-wax EC by canopy leaf area index, while EC flux to soil was estimated by multiplying in-wax EC by leaf litterfall mass. This study shows that through retention of EC in leaf waxes, urban tree canopies represent important short-term sinks for soot in urban areas.
Using Machine Learning to Develop a Calibration Model for Low-Cost Air Quality Sensors Deployed during a Dust Event
Low-cost sensors have the potential to create dense air monitoring networks that help enhance our understanding of pollution exposure and variability at the individual and neighborhood-level; however, sensors can be easily influenced by environmental conditions, resulting in performance inconsistencies across monitoring settings. During summer 2020, 20 low-cost particulate sensors were deployed with a reference PM2.5 monitor in Denton, Texas in preparation for calibration. However, from mid to late-summer, dust transported by the Saharan Air Layer moved through the North Texas region periodically, influencing the typical monitoring pattern exhibited between low-cost sensors and reference instruments. Traditional modeling strategies were adapted to develop a new approach to calibrating low-cost particulate sensors. In this study, data collected by sensors was split according to a novel dust filter into dust and non-dust subsets prior to modeling. This approach was compared with building a single model from the data, as is typically done in other studies. Random forest and multiple linear regression algorithms were used to train models for both strategies. The best performing split-model strategy, the multiple linear regression models split according to dust and non-dust subsets (combined R2 = 0.65), outperformed the best performing single-model strategy, a random forest model (R2 = 0.49). The results from this study indicate that low-cost sensor performance can be greatly influenced by the presence of dust, and that adaptive strategies, like the ones presented in this paper, are necessary when calibrating sensors in environments that may experience pollution from inconsistent sources throughout the year.
What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, Texas
Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.
Wildfire Influence on Rainfall Chemistry and Deposition in Texas during the 2011-2014 Drought
From 2011 to 2014, one of the most severe and intense droughts in Texas recorded history led to widespread wildfires across the state, with unknown effects on atmospheric nutrient and pollutant deposition. The objectives of this research were to: (1) characterize the frequency, magnitude, and spatiotemporal distribution of Texas wildfires (2011-2014); (2) identify smoke occurrence and source regions at eight Texas National Atmospheric Deposition Program (NADP) National Trends Network (NTN) sites (2011); and (3) quantify the influence of wildfire on weekly rainwater chemistry and deposition in 2011 at three NADP sites (Sonora, LBJ Grasslands, Attwater Prairie NWR). Data on large wildfires, smoke occurrence, and rainfall chemistry and deposition were coupled with principal component and back-trajectory analysis to address these objectives. Between 2011-2014, 72% of all wildfires occurred in 2011, accounting for 90% of the total area burned. In total, there were 17 extreme wildfires (i.e., in the 95th percentile of hectares burned), of which 11 occurred in 2011. Wildfire activity was concentrated in West Texas ecoregions and consumed primarily shrub/scrub and grassland/herbaceous land cover. Although West Texas experienced the most wildfires, smoke at the NADP locations in 2011, the "high-fire year," was more frequent in East Texas due to regional wind patterns transporting smoke from diverse source locations. In 2011, weeks with smoke-influenced rain events––defined as weeks in which the rainfall event air mass trajectory intersected a smoke polygon, at any time, for at least one hour in the 72-hours prior to rainfall at the NADP site––had higher concentrations of Ca2+, Mg2+, K+, NH4+, and SO42- compared to background samples (not affected by smoke). At LBJ Grasslands, four smoke-influenced rain samples deposited >49% of annual wet deposition for all ions. Principal component analysis identified wildfire as a key component contributing to the variance in the dataset. Taken together, these findings …
Women in Wrestling Arenas: How Globalization, Socially Produced Spaces, and Commodification Impact their Portrayal and Empowerment Post Women's Revolution
The Women's Revolution in 2015 has led to a drastic shift in the ways women are portrayed in professional wrestling. The Women's Revolution came as a result of the social unrest over the lack of time women were receiving on the televised shows. Where women's storylines had centered on their sexuality, they are now presented as equal to their male counterparts after the Women's Revolution. Through an exploration of concepts in globalization, commodification, and socially produced spaces, this research seeks to understand and contextualize the Women's Revolution, the degree to which the portrayed women's equality has been achieved, and the resulting impacts of the female superstars overall. I argue that that this "equality" has been achieved through inscribing the traditionally masculine qualities of wrestling to women, has resulted in an unequal distribution of opportunities to particular female superstars rather than equality for all women on the shows, and that phallocentric objectification of the female superstars still occurs in certain aspects of professional wrestling.
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