Digital Commons Network^™

Removal Of Disinfection By-Product Precursors Using Magnetic Ion Exchange (Miex(R)): The Effects Of Ph And Source Water Variability, Sarah Cousins

Graduate Theses and Dissertations

Disinfection by-products (DBPs) form as an unintended result of drinking water disinfection, from chemical reactions between disinfectants (e.g., free chlorine) and naturally occurring dissolved organic matter (DOM). At present, 11 DBPs are regulated in treated drinking waters due to potential adverse health effects, including four trihalomethanes (THMs). Despite nearly 40 years of DBP research, compliance with DBP regulations remains a challenge for many drinking water treatment plants (DWTPs), including the four DWTPs located on the Beaver Lake Reservoir in Northwest Arkansas. Due to the high net negative surface charge on DOM, anion exchange is one potentially viable method for removing …

Analyzing Spring Freeze Impacts On Deciduous Forest Productivity Using Modis Satellite Imagery, Karl Lintvedt

Graduate Theses and Dissertations

The impacts of an April 2007 spring freeze event on the productivity of deciduous broadleaf forest were analyzed using geographic information system (GIS) tools. Forest productivity was modeled using the Enhanced Vegetation Index (EVI), as recorded by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor. Measures of spatial autocorrelation were used to quantify the degree of spatial congruence between a map depicting the severity of the freeze event, and maps modeling forest productivity throughout the year. The results show a geographic correlation between the unseasonably low minimum temperatures sustained during the freeze and the unusually low forest productivity that followed. …

Water Quality Trends For Section 319 Priority Watersheds In Northwest Arkansas, 1997-2010, Bryan William Bailey

Graduate Theses and Dissertations

Northwest Arkansas contains two Section 319 Priority Watersheds that the Arkansas Natural Resources Commission (ANRC) has identified as being impacted by point and nonpoint sources of pollution (i.e., phosphorus, nitrogen, and sediment), and the Arkansas Water Resources Center (AWRC) has monitored the water quality at several sites within these watersheds. Water-quality data has been collected over the last decade within the Illinois River Watershed (HUC #11110103) and the Upper White River Basin (Beaver Reservoir HUC# 11010001), each watershed containing three sampling sites. The Illinois River Watershed sites are located on the Illinois River, Osage Creek, and Ballard Creek, and the …

Geospatial Tools And Techniques For Watershed Management Using Swat 2009, Naresh Pai

Graduate Theses and Dissertations

In this study, geospatial tools and techniques were developed to support specific aspects of watershed pollution management, such as quantifying land-use change (LUC) impacts, prioritizing subwatersheds, and communicating field-scale impacts, using the soil and water assessment tool 2009 (SWAT 2009) model.

For the land-use change objective, a geospatial tool titled SWAT2009_LUC was developed that enables SWAT modelers to prepare specific input files for simulating concurrent land-use changes during the SWAT 2009 model simulations. Testing of the tool for the Illinois River Drainage Area in Arkansas (IRDAA) watershed showed that the tool accurately represented temporal land-uses within the model. Model simulations …

Subcritical Water Hydrolysis Of Whey Proteins, Ashley Dawn Espinoza

Graduate Theses and Dissertations

Hydrolyzing food by-products is a unique approach to potentially increase by-product value and reduce waste. An abundant by-product of cheese production, whey, contains all essential amino acids and some distinctive peptides with functional and nutraceutical properties. Typically, proteins from whey are tailored for specific uses by chemical or enzymatic hydrolysis; however, subcritical water hydrolysis is a novel alternative used successfully to hydrolyze various substrates. Nevertheless, minimal research exists on: (1) the hydrolysis of whey protein; (2) the incorporation of additives; (3) the hydrolysis of whole whey; and (4) the production of volatiles when using subcritical water hydrolysis.

Therefore, whey protein …

Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem

Graduate Theses and Dissertations

In Jordan, demand for water for agricultural purposes has put a high strain on aquifer resources. Water mining, erosion, and desertification have all increased as global temperatures rise. This along with fragmentation of the landscape have altered the environment in a profound way. The Madaba Plain was chosen for this study due to the agricultural activities that take place there, as well as the proximity to a number of population centers. The purpose of the study is to examine how fragmentation of irrigated landscape has affected the aquifers underneath, while taking into account perceptions of risk of the local population. …

Estimating Cost Efficiencies Of Propane Use In Broiler Production: Case Study From Savoy, Arkansas And Trnaca Pri Laborci, Slovak Republic, Zuzana Petrikova

Graduate Theses and Dissertations

This study focuses on analyzing the common practice of U.S. broiler farmers to operate on cash basis instead open credit lines for operating cost of propane gas for heating. Data for analysis were taken over from U.S. ABRF at Savoy and Slovak Farm Univerza at Trnava pri Laborci. Predicting the propane gas usage and propane gas cost was analyzed using the OLS model. It describes impact of selected factors on gas usage and cost. The overall purpose of the thesis is to find out which approach from designed scenarios is more economically efficient for farmer: (a) to pre-purchase propane gas …

Assessing Ageing At Beaver Reservoir, Northwest Arkansas: Limnological, Geochemical & Paleolimnological Approach, Byron Anthony Winston

Graduate Theses and Dissertations

Access to potable water has been arguably one of the most important requisites for the advancement of human civilization on earth. As a result, man in his infinite wisdom devised the dam and formed reservoirs, (man- made lakes), to exploit water resources at will. In all natural lakes and reservoirs changes occur in the water quality parameters as it relates to chemical nutrients, temperature and turbidity over time. These changes are collectively referred to as "Reservoir Ageing", of which sedimentation and eutrophication are primary. Reservoir Ageing has consequences which adversely affect and defeat many of the intended uses of the …

Spatial Variations In Willingness To Pay For Water At The Local And Regional Scales Using Geographically Weighted Regression, Robyn Lane Dennis

Graduate Theses and Dissertations

Two decades of rapid urban growth and increasing per capita water consumption has left water providers in Northwest Arkansas concerned about their ability to meet future demand for water. Beaver Water District (BWD) is the largest of four regional water providers that draw from Beaver Lake, the only source of potable water in the region. Growth projections and per capita consumption patterns indicate that BWD could exhaust its raw water allocation as early as 2031. Municipal water customers served by BWD were surveyed about their stated priorities for water use, their water conservation behaviors, and their attitudes and perceptions about …