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Full-Text Articles in Social and Behavioral Sciences

Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner May 2017

Development Of A Multiband Remote Sensing System For Determination Of Unsaturated Soil Properties, Cyrus D. Garner

Graduate Theses and Dissertations

A multiband system including active microwave sensing and visible-near infrared reflectance spectroscopy was developed to measure unsaturated soil properties in both field and laboratory environments. Remote measurements of soil volumetric water content (θv), soil water matric potential (ψ), and soil index properties (liquid limit [LL], plastic limit [PL], and clay fraction [CF]) were conducted. Field-based measurement of θv was conducted using a ground-based radar system and field measurements within 10 percentage points of measurements acquired with traditional sampling techniques were obtained. Laboratory-based, visible and near infrared spectroscopy was found to be capable of obtaining empirical, soil specific regression functions (partial …


Environmental And Climatic Constraints On Large-Scale Camelina Production In Eastern Arkansas, Benjamin Robert Tracy May 2017

Environmental And Climatic Constraints On Large-Scale Camelina Production In Eastern Arkansas, Benjamin Robert Tracy

Graduate Theses and Dissertations

Camelina sativa is a cold weather crop that is typically grown in semi-arid environments in the Western United States, usually as a spring crop, but sometimes during the winter. Research analyzing climate data and soil hydrology is important to better understand the environmental and terrain conditions necessary for Camelina farming wherever it is proposed for large-scale production. This study focused on various conditions and constraints pertaining to the potential for Camelina as a crop biofuel in Eastern Arkansas. Due to interest in the economic potential of crop biofuels in this area, and in particular the low input costs for Camelina, …


A Gis Approach To Modeling Groundwater Levels In The Mississippi River Valley Alluvial Aquifer, Josef Orion Lilly Dec 2016

A Gis Approach To Modeling Groundwater Levels In The Mississippi River Valley Alluvial Aquifer, Josef Orion Lilly

Graduate Theses and Dissertations

Groundwater depletion, a subject of growing concern for a significant portion of Arkansas, may lead to future economic challenges for the Arkansas Delta region. The Mississippi River Valley Alluvial Aquifer is the uppermost aquifer and features the largest groundwater capacity in the Mississippi Embayment Aquifer System. The Mississippi River Valley Alluvial Aquifer, commonly referred to as the “alluvial aquifer”, spans 53,000〖 km〗^2 underlying portions of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, Illinois, and Tennessee. As the alluvial aquifer trends southward for approximately 250 miles alongside the Mississippi River, its geographical extent ranges from 50 to 125 miles wide. There is a …


Lidar-Assisted Extraction Of Old Growth Baldcypress Stands Along The Black River Of North Carolina, Weston Pierce Murch Aug 2016

Lidar-Assisted Extraction Of Old Growth Baldcypress Stands Along The Black River Of North Carolina, Weston Pierce Murch

Graduate Theses and Dissertations

The remnants of ancient baldcypress forests continue to grow across the Southeastern United States. These long lived trees are invaluable for biodiversity along riverine ecosystems, provide habitat to a myriad of animal species, and augment the proxy climate record for North America. While extensive logging of the areas along the Black River in North Carolina has mostly decimated ancient forests of many species including the baldcypress, conservation efforts from The Nature Conservancy and other partners are under way. In order to more efficiently find and study these enduring stands of baldcypress, some of which are estimated to be more than …


Geospatial Analysis Of Droughts, Rice And Wheat Production, And Agrarian Vulnerability: A District-Level Study Of The Self-Calibrated Palmer Drought Severity Index In India, Aaron Michael Shew May 2016

Geospatial Analysis Of Droughts, Rice And Wheat Production, And Agrarian Vulnerability: A District-Level Study Of The Self-Calibrated Palmer Drought Severity Index In India, Aaron Michael Shew

Graduate Theses and Dissertations

Droughts have affected more people than any other natural disaster in the last century, causing billions in economic damages and millions of deaths. As the Sea Surface Temperatures (SST) have heated in the Indian Ocean, drought patterns across South Asia have changed; the Indian monsoon has become more volatile and less predictable. In this study, monthly self-calibrated Palmer Drought Severity Index (sc-PDSI) data for the time period between 1950 and 2009 were interpolated to India’s districts; then the data were analyzed for changes in frequency and severity. The data were further evaluated using Anselin’s Local Moran’s I Statistic to elicit …


Evaluation Of Conservation Practices Through Simulation Modeling And Tool Development, Gurdeep Singh Dec 2015

Evaluation Of Conservation Practices Through Simulation Modeling And Tool Development, Gurdeep Singh

Graduate Theses and Dissertations

For the first objective, predicted impacts of selected Mississippi River Basin Initiative (MRBI) conservation practices (CPs) on sediment and nutrient loss were assessed. The study area was L’Anguille River Watershed (LRW), a priority focus watershed of the MRBI program and the simulated CPs were filter strip, critical area planting, grade stabilization structure, irrigation land leveling, irrigation pipeline, irrigation water management, and nutrient management. The Soil and Water Assessment Tool (SWAT) model was calibrated (1998 – 2005) and validated (2006 – 2012) for flow, sediment, total phosphorus (TP), and nitrate-nitrogen (NO3-N) at the Colt site (503 sq. km. drainage area) and …


Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy Dec 2015

Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy

Graduate Theses and Dissertations

The WCL (Wet Chemistry Lab) instrument on board the Mars’s Phoenix Lander has identified the soluble ionic composition of the soil at the landing site. Two important ions were detected at the landing site; perchlorates (ClO4-) with a concentration of ~ 2.4 wt% and chlorides (Cl-) with a concentration of 0.54 wt%. Between chloride and perchlorate ions three other oxidized ions exist and called chlorine ions: hypochlorite ClO - (ox. state +1), chlorite ClO2- (ox. state +3) and chlorate ClO3- (ox. state +5). These oxidized ions might be existed as intermediate species on the surface of Mars but remained undetected. …


Solubility And Detectability Of Hydrocarbons On The Surface Of Titan, Sandeep Singh Jul 2015

Solubility And Detectability Of Hydrocarbons On The Surface Of Titan, Sandeep Singh

Graduate Theses and Dissertations

Titan’s thick atmosphere is enriched with organic compounds and its surface holds reservoirs of hydrocarbons. This makes Titan the only other candidate in our solar system (apart from Earth) to have stable liquid at the surface. The stability and characteristics of liquid and ices on the surface of Titan are of high importance in understanding its surface-atmosphere interactions. Titan’s hydrological cycle is similar to what we see on Earth, with the exception of methane (CH4) and ethane (C2H6) taking the place of water. The smoggy atmosphere veils the surface of Titan from the view of Cassini spacecraft, except at seven …


Mapping Ancient Baldcypress Forests For Conservation At Black River, North Carolina, Jordan Nichole Burns May 2015

Mapping Ancient Baldcypress Forests For Conservation At Black River, North Carolina, Jordan Nichole Burns

Graduate Theses and Dissertations

A few ancient baldcypress-bottomland hardwood forests survive across the southeastern United States in a mosaic of remnant old-growth stands left untouched by extensive logging during the early 20th century. Uncut stands in the Southeast that survived centuries of disturbance following European settlement tended to be too senescent and non-commercial to justify logging. Remnant ancient baldcypress forests at Black River, North Carolina, appear to contain the oldest living trees in eastern North America and The Nature Conservancy has protected several of these stands. However, the full extent of ancient bottomland forests along Black River is not known and many valuable tracts …


Toolstone Use In Ozark Prehistory: Assessing Adaptations To A Lithic Dichotomy In The Boston Mountains And Springfield Plateau, Luke Allen Morris May 2015

Toolstone Use In Ozark Prehistory: Assessing Adaptations To A Lithic Dichotomy In The Boston Mountains And Springfield Plateau, Luke Allen Morris

Graduate Theses and Dissertations

Toolstone use in the Ozark Mountains is a reactionary process reliant on how the landscape provides or constrains chipped stone for prehistoric populations. These technological adaptations are recognized at sites throughout the area, but no regional assessment of lithic assemblages provides answers as to why certain stones are used at a particular location. This thesis employs a five step mass analysis of lithic assemblages, and GIS visualizations to observe how the organization of stone technologies vary based on location within contrasting geologic contexts. The chert-bearing Springfield Plateau, and the Boston Mountains with siltstone, are two neighboring dichotomous landscapes that illustrate …


Bedrock Geological Map Of The Rockhouse Quadrangle, Carroll And Madison Counties, Arkansas, Douglas Eben Jones Dec 2013

Bedrock Geological Map Of The Rockhouse Quadrangle, Carroll And Madison Counties, Arkansas, Douglas Eben Jones

Graduate Theses and Dissertations

A digital geologic map of the Rockhouse quadrangle, Carroll and Madison counties, Arkansas, was created on a 1:24,000 scale using ArcMap 10 and Photoshop CS4. The data obtained in the field are digitized onto the United States Geological Survey (USGS) digital raster graphic (DRG) of the Rockhouse quadrangle. The geology in the Rockhouse quadrangle consist entirely of sedimentary rocks that are Paleozoic ranging from Lower Ordovician to Mississippian in age. The Ordovician System is represented by the Cotter, Powell, Everton, and St. Peter Formations. The Cotter and Powell are the prominent bluff forming units throughout the quadrangle and along the …


A Geomechanical Study Of The Mississippian Boone Formation, Karen Nicole Mason Buckland Aug 2013

A Geomechanical Study Of The Mississippian Boone Formation, Karen Nicole Mason Buckland

Graduate Theses and Dissertations

The Boone Formation in northwest Arkansas is a chert-limestone sequence analogous to the subsurface Mississippi Lime reservoir in parts of Oklahoma and Kansas. It has low permeability and produces via horizontal drilling and hydraulic fracturing. The response to stimulation by fracturing is dependent on the quantity of chert in the area. Chert nodules and laterally extensive chert layers in the sequence are variable. Locally, cm- to dm-scale chert bedding is continuous and comprises up to 50% of the outcrop. Elsewhere, the chert is nodular and intermittent.

Samples collected from representative outcrops spanning the thickness and aerial extent of the formation …


Classification Of Satellite Time Series-Derived Land Surface Phenology Focused On The Northern Fertile Crescent, Brian Embree Bunker May 2013

Classification Of Satellite Time Series-Derived Land Surface Phenology Focused On The Northern Fertile Crescent, Brian Embree Bunker

Graduate Theses and Dissertations

Land surface phenology describes events in a seasonal vegetation cycle and can be used in a variety of applications from predicting onset of future drought conditions, to revealing potential limits of historical dry farming, to guiding more accurate dating of archeological sites. Traditional methods of monitoring vegetation phenology use data collected in situ. However, vegetation health indices derived from satellite remote sensor data, such as the normalized difference vegetation index (NDVI), have been used as proxy for vegetation phenology due to their repeated acquisition and broad area coverage. Land surface phenology is accessible in the NDVI satellite record when images …


Agricultural Production And Stability Of Settlement Systems In Upper Mesopotamia During The Early Bronze Age (Third Millennium Bce), Tuna Kalayci May 2013

Agricultural Production And Stability Of Settlement Systems In Upper Mesopotamia During The Early Bronze Age (Third Millennium Bce), Tuna Kalayci

Graduate Theses and Dissertations

This study investigates the relationship between rainfall variation and rain-fed agricultural production in Upper Mesopotamia with a specific focus on Early Bronze Age urban settlements. In return, the variation in production is used to explore stability of urban settlement systems. The organization of the flow of agricultural goods is the key to sustaining the total settlement system.

The vulnerability of a settlement system increases due to the increased demand for more output from agricultural lands. This demand is the key for the success of urbanization project. However, without estimating how many foodstuffs were available at the end of a production …


Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann Dec 2012

Prehistoric Human Ecodynamics In The Rub Al-Khali Desert: Results Of Remote Sensing And Excavations In Dubai, United Arab Emirates, Jason T. Herrmann

Graduate Theses and Dissertations

Archaeological investigations in the Emirate of Dubai, UAE conducted by the Dubai Department of Archaeology and the University of Arkansas demonstrate that the desert inland of the Oman Peninsula was occupied not only during the Arabian Neolithic (8000-4400 BC), when the region experienced a moist period referred to as the Holocene Climatic Optimum (HCO), but also during the more arid millennia following the decline of the HCO into the Christian Era. During this period, desert settlement clustered near a band of oases, in contrast to the more widespread spatial distribution of remains of nomadic pastoralists from the Neolithic. Excavations at …


Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser May 2012

Geoarchaeology Of The Orontes River Floodplain Surrounding Tell Qarqur, Syria, Anna Flora Wieser

Graduate Theses and Dissertations

This project combines geoarchaeological soil description and GIS analysis of archaeological site distribution to investigate the history of marsh formation in the northern Ghab Basin, located within the Orontes River Valley of western Syria. Tell Qarqur, the archaeological site around which this project is focused, has a continuous occupational sequence throughout the Holocene. Annual inundation of the site by seasonal marshlands suggests that the marsh was either smaller or non-existent in the past, but its history remains unknown. The objectives of this investigation are to interpret the nature of depositional environments, particularly fluvial action, in the vicinity of Tell Qarqur, …


Integrating Human Variables In Cross-Boundary Monitoring Of Aberdare Preserves In Kenya, Peter K. Njuguna May 2012

Integrating Human Variables In Cross-Boundary Monitoring Of Aberdare Preserves In Kenya, Peter K. Njuguna

Graduate Theses and Dissertations

This research critically examines extant data systems and their linkage of scientific research to policy and public education in east African highland forest conservation preserves. The research indicates that the current state of data and monitoring systems in the region imposes substantial limitations on the ability to manage these preserves. Major outcomes of those constraints manifest in unprecedented cross-boundary pressure such as encroachment and conversion of forest to agriculture, increased human-wildlife conflicts, and constrained relations among primary stakeholders. Current monitoring is biodiversity focused within preserves and fails to capture human dimensions in adjoining areas across preserve boundaries. This study proposes …


Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan May 2012

Role Of Vegetation And Environmental Characteristics On Slope Stability In Northwest Arkansas, Michael Maguigan

Graduate Theses and Dissertations

Slope failure continues to pose risks to society because knowledge of environmental factors and their interactions are unclear and possibly misunderstood. This misunderstanding leads to generalizations about slope failure susceptibility mapping, despite knowing that slope failures are likely the result of an extensively complex set of interactions among a number of environmental, edaphic, and geomorphic characteristics. Therefore a series of experiments were conducted to investigate the effects of slope, soil texture, vegetation cover, bedrock permeability, and compaction,. A wooden flume with a slope face 1 m wide by 1.5 m long with a 10 cm toe was constructed to contain …


Identifying Optimal Cellulosic Biomass Feedstock Supply Areas For Potential Biorefineries In Arkansas, Mark Cooper May 2012

Identifying Optimal Cellulosic Biomass Feedstock Supply Areas For Potential Biorefineries In Arkansas, Mark Cooper

Graduate Theses and Dissertations

In February 2010, the U.S. Environmental Protection Agency released the revised Renewable Fuel Standard (RFS2), mandating at least 36 billion gallons of renewable fuels to be produced annually in America, and blended into all on/off road, locomotive, and marine gasoline and diesel by the year 2022. America's existing biorefineries fall significantly short of being able to meet this mandate, resulting in the need for rapid expansion in the near future if this goal is to be met. The state of Arkansas has abundant resources to offer the renewable energy industry, if properly utilized. The goal of this thesis is to …


Analyzing Spring Freeze Impacts On Deciduous Forest Productivity Using Modis Satellite Imagery, Karl Lintvedt Dec 2011

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. …