Developing a Soil Moisture-Based Irrigation Scheduling Tool (SMIST) Using Web-GIS Technology (open access)

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 …
Date: May 2018
Creator: Nikfal, Mohammadreza
System: The UNT Digital Library
Public Market Trade Areas:  Local Goods, Farmers, and Community in the U.S. Southwest Region, 1996-2016 (open access)

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 …
Date: May 2018
Creator: Oppenheim, Vicki Ann
System: The UNT Digital Library
Urban Trees as Sinks for Soot: Deposition of Atmospheric Elemental Carbon to Oak Canopies and Litterfall Flux to Soil (open access)

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 …
Date: May 2018
Creator: Rindy, Jenna
System: The UNT Digital Library

Green Entrepreneurialism and the Making of the Trinity River Corridor: The Intersection of Nature and Capital in Dallas, Texas

Access: Use of this item is restricted to the UNT Community
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 …
Date: May 2019
Creator: Krupala, Katie Ilene
System: The UNT Digital Library
Reconstructing Identity with Urban Community Agriculture: How Refugees Confront Displacement, Food Insecurity, and Othering through Community Farming (open access)

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 …
Date: May 2017
Creator: Griffin, Marinda
System: The UNT Digital Library
Assessing Rainfall Interception by Urban Tree Canopies in Denton, Texas (open access)

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 ± …
Date: May 2017
Creator: Edington, Patrick
System: The UNT Digital Library