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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