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Articles 241 - 270 of 339
Full-Text Articles in Earth Sciences
Metal Mobilization In Groundwater, Bauxite, Ar, Steven Alexander Hamlin
Metal Mobilization In Groundwater, Bauxite, Ar, Steven Alexander Hamlin
Graduate Theses and Dissertations
The Wilcox Aquifer of Bauxite, AR contains bauxite ore deposits that may contribute heavy metals to groundwater. Twenty-four wells were sampled for aluminum, iron, manganese, zinc, lead, barium, nitrate, sulfate, sodium, alkalinity, calcium, magnesium, chloride, pH, total organic carbon, and total dissolved solids. A Wilcoxon Rank-Sum compared the similarity of the three geographic areas covered in the study. All parameters for wells in Bauxite and Sardis failed to reject the null hypothesis, signifying that wells all occupy the Saline Formation. 2/3rds of the parameters from BFI261 and the Bauxite region did not agree, suggesting the two areas do not occupy …
Paleoclimate Implications From Stable Isotope Analysis Of Sedimentary Organic Carbon And Vertebrate Fossils From The Cedar Mountain Formation, Ut, U.S.A., Garrett Andrew Hatzell
Paleoclimate Implications From Stable Isotope Analysis Of Sedimentary Organic Carbon And Vertebrate Fossils From The Cedar Mountain Formation, Ut, U.S.A., Garrett Andrew Hatzell
Graduate Theses and Dissertations
Oxygen and carbon isotopic compositions of fossilized vertebrate teeth and bone were analyzed to determine isotopic values of vertebrate faunal diet from the early Cretaceous Cedar Mountain Formation of Utah. Results for δ18O of PO4 (δ18Op) (Suarez et al., 2014) from the same data set have been compared to the δ18O of CO3 (δ18Oc) portion of teeth and turtle shell to determine if diagenetic alteration of the isotopes has occurred by plotting the line of best fit equation that models the relationship between unaltered δ18OP and δ18OC of modern mammals from Iacumin et al., 1996. Results indicate slight diagenesis of …
The Functional And Distributional Ecology Of Mycetozoans Under Changing Edaphic And Climatic Dynamics, Geoffrey Lloyd Zahn
The Functional And Distributional Ecology Of Mycetozoans Under Changing Edaphic And Climatic Dynamics, Geoffrey Lloyd Zahn
Graduate Theses and Dissertations
Investigations into the distribution and ecosystem functions of fruiting amoebae revealed that local-scale environmental conditions can largely explain broad biogeographical patterns in species assemblage, the way in which amoeboid predators shape bacterial communities and how this top-down influence may affect global biogeochemical processes in a changing climate. The distribution and assemblage of protosteloid amoebae on the islands of New Zealand and Hawaii did not yield any expected patterns of island biogeography, and conformed to other global regions studied. The strongest predictor of species richness in a given region was sampling effort and these species do not appear to have any …
Solubility And Detectability Of Hydrocarbons On The Surface Of Titan, Sandeep Singh
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 …
Stable Isotopes As A Tool To Characterize Carbon Cycling And Develop Hydrologic Budgets In Mantled Karst Settings, Katherine Knierim
Stable Isotopes As A Tool To Characterize Carbon Cycling And Develop Hydrologic Budgets In Mantled Karst Settings, Katherine Knierim
Graduate Theses and Dissertations
Isotopes of water (δ2H/δ18O), carbon dioxide (δ13C-CO2), and dissolved inorganic carbon (δ13C-DIC) were used to explore water quality, trace carbon cycling, and quantify recharge sources through mantled karst and into Blowing Spring Cave (BSC). Of the possible sources of contamination in the BSC recharge area, septic-tank effluent was hypothesized to degrade water quality at the spring outlet of BSC because of the dominance of septic tanks for waste treatment, unsuitable topography and soil for septic-tank absorption fields, increased nitrate and chloride concentrations concomitant with increased urbanization, and increased Escherichia coli with discharge. Carbon cycling between the soil and BSC was …
Toolstone Use In Ozark Prehistory: Assessing Adaptations To A Lithic Dichotomy In The Boston Mountains And Springfield Plateau, Luke Allen Morris
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 …
Controls On Dissolution Rate Variation At A Pair Of Underflow-Overflow Springs At The Savoy Experimental Watershed, Kiefer Allen Vaughn
Controls On Dissolution Rate Variation At A Pair Of Underflow-Overflow Springs At The Savoy Experimental Watershed, Kiefer Allen Vaughn
Graduate Theses and Dissertations
Physical dissolution experiments and numerical modeling have been used in the past to study limestone dissolution rates. Numerical models have typically used constant dissolution rates, whereas rates in nature vary in time. Limestone tablets allow natural estimation of rates over month time scales, but these rates cannot necessarily be extrapolated to geologic timescales and also do not aid our understanding of short term variability. This study characterizes natural variability in these rates and examines potential causes of that variability from first principles. This may enable more accurate projections of dissolution rates within models. This study combines measurement of physical and …
Rice Grain Yield And Nitrogen Uptake And Ammonia Volatilization From Urea As Affected By Urea Amendment And Simulated Rainfall, Randy Dempsey
Rice Grain Yield And Nitrogen Uptake And Ammonia Volatilization From Urea As Affected By Urea Amendment And Simulated Rainfall, Randy Dempsey
Graduate Theses and Dissertations
The effect of rainfall between urea application and flood establishment on N loss and grain yield of rice (Oryza sativa L.) has not been studied. The first research objective was to compare the effects of simulated rainfall amounts and N-(n-butyl) thiophosphoric triamide (NBPT) urease inhibitor rate on NH3 volatilization and rice growth. Three field experiments were conducted and NH3 volatilization was measured in two experiments for 11 days after urea application (DAU) in semi-open chambers. Urea or NBPT-treated urea (NBPT-Urea) was subjected to six simulated rainfall amounts (0-25 mm) applied 5 to 15 h after urea application and flooded 7 …
Pennsylvanian Subsurface Sequence Stratigraphy Based On 3d Seismic And Wireline Data In Western Osage County, Oklahoma, Alexander West
Pennsylvanian Subsurface Sequence Stratigraphy Based On 3d Seismic And Wireline Data In Western Osage County, Oklahoma, Alexander West
Graduate Theses and Dissertations
The Pennsylvanian System in the Mid-Continent United States has been studied for nearly a century. In north central Oklahoma, the Pennsylvanian is primarily composed of cyclothems. These cyclothems are sequences of alternating carbonate, clastic, and shale members. Because of this, these zones can be difficult to differentiate. This project provides valuable insight into better understanding the Pennsylvanian System in western Osage County, Oklahoma. The scope of this project is to perform a subsurface study to produce a detailed interpretation of the depositional history and stratigraphy of Pennsylvanian sequences in western Osage County.
This study features 3D seismic and well log …
Stratigraphic Analysis With Respect To Aggregate Potential In The Duffield Quarry In Gum Log, Arkansas, Brock Evan Langford
Stratigraphic Analysis With Respect To Aggregate Potential In The Duffield Quarry In Gum Log, Arkansas, Brock Evan Langford
Graduate Theses and Dissertations
The crushed stone mining industry is valued at nearly one billion dollars in Arkansas alone. Physical properties of the rock dictate whether or not an area may be suited for the establishment of an aggregate quarry. The Gum Log quarry located 10 miles northeast of Russellville, Arkansas is geographically well situated near areas in need of aggregate material, as well as physically competent rock. The rock mined in Gum Log is located in the Upper Atoka Formation, a Middle Pennsylvanian aged member of the Arkoma Basin. There are five different lithologic facies identifiable in the quarry (Facies 1-5 respectively): A …
Subsurface Fluid Flow Through The Mississippian Section Of North-Central Oklahoma, Carolyn Brown
Subsurface Fluid Flow Through The Mississippian Section Of North-Central Oklahoma, Carolyn Brown
Graduate Theses and Dissertations
This study consisted of using drill stem tests, seismic amplitude data, and well logs to create the parameters needed to construct a groundwater flow model for a portion of Osage County. At the start, a potentiometric map of Osage County, Oklahoma was generated to use as a basis for the initial hydraulic heads and the constant heads in the model. Next, three seismic amplitude images were produced in a seismic interpretation program, OpenDtect, to base the hydraulic conductivity values on. In addition, utilizing Gamma Ray on 12 separate wells east-west across the county, a structural cross-section was created within Petra. …
Stratigraphic Characterization And Depositional History Of The Barnett Shale Within The Fort Worth Basin In Denton County, Texas, Matthew Loren Cope
Stratigraphic Characterization And Depositional History Of The Barnett Shale Within The Fort Worth Basin In Denton County, Texas, Matthew Loren Cope
Graduate Theses and Dissertations
The Barnett shale, located in the Fort Worth Basin, is a geologic unit that has undergone extensive study and currently holds great economic importance. It contains well-known stratigraphy, but still holds questions with regard to the specific stratigraphic variation over much of its area. Denton County contains a large geographic area of the Barnett shale, and holds many answers to the varying stratigraphy of the Barnett shale, as well as an explanation into its depositional history. The investigation involved the use of two cross sections utilizing 32 and 26 wells respectively in the western region of Denton County, Texas. From …
Analysis Of Paleokarst Sinkholes In The Arkoma Basin Using 3-D Seismic, Michael Kumbalek
Analysis Of Paleokarst Sinkholes In The Arkoma Basin Using 3-D Seismic, Michael Kumbalek
Graduate Theses and Dissertations
Paleokarst features are important to understand, both with regards to research geologists and to the petroleum industry. In terms of geology, understanding paleokarst features can yield more information about the depositional and surface environments of past times, and how diagenetic alteration affected the environment during the formation of karst features. In the petroleum industry, paleokarst features can have positive or negative consequence resulting in a potential reservoir with enhanced porosity due to the paleokarst features, or as a geo-hazard to prepare for or avoid when drilling.
Inspired by issues faced when drilling in the Ft. Worth basin, this study utilizes …
Methane Emissions From Direct-Seeded, Delayed-Flood Rice Grown On A Clay Soil, Alden Daniel Smartt
Methane Emissions From Direct-Seeded, Delayed-Flood Rice Grown On A Clay Soil, Alden Daniel Smartt
Graduate Theses and Dissertations
Due to the production of methane (CH4) under flooded-soil conditions, rice (Oryza sativa L.) cultivation is a major contributor to agricultural CH4 emissions. Studies examining CH4 emissions from rice have only recently been initiated in Arkansas and no data have been collected from rice produced on clay soils in Arkansas. Therefore, research was conducted in 2012 and 2013 at the Northeast Research and Extension Center in Keiser, Arkansas to examine the factors affecting CH4 emissions from rice produced on a Sharkey clay (very-fine, smectitic, thermic Chromic Epiaquerts). The objectives of this study were to determine: 1) the effect of vegetation …
Terrestrial Impacts Of The Central Atlantic Magmatic Province On Western Pangea, Todd Kenneth Knobbe
Terrestrial Impacts Of The Central Atlantic Magmatic Province On Western Pangea, Todd Kenneth Knobbe
Graduate Theses and Dissertations
Earth's climate is predominantly controlled by the fluctuation of greenhouse gases, specifically CO2 and CH4, over geologic time. The late Triassic is a period of abrupt climate change that has been associated with a disruption to the global carbon cycle due the emplacement of the Central Atlantic Magmatic Province (CAMP). Evidence has shown that this global carbon cycle perturbation may be the culprit for the end-Triassic extinction. The Whitmore Point Member of the Moenave Formation is a lacustrine deposit with a disputed age of either late Triassic or early Jurassic and currently no absolute dating techniques can be applied to …
Interpretation Of Late Cretaceous Volcanic Mounds And Surrounding Gulfian Series Formations Using 3d Seismic Data In Zavala County, Texas, Laura Claire Bennett
Interpretation Of Late Cretaceous Volcanic Mounds And Surrounding Gulfian Series Formations Using 3d Seismic Data In Zavala County, Texas, Laura Claire Bennett
Graduate Theses and Dissertations
The Late Cretaceous Gulfian series is a prominent and important series across the State of Texas that has been extensively studied since the nineteenth century. It is composed of series of southeast-dipping shelf carbonates and clastics deposited on the northwest margin of the Gulf of Mexico Basin. In south Texas, the Gulfian series was deposited in the Rio Grande Embayment and Maverick Basin and is comprised of the Eagle Ford Group, Austin Group, Anacacho Limestone, San Miguel Formation, Olmos Formation, and Escondido Formation that crop out and continue basinward in the subsurface. Late Cretaceous volcanism formed volcanic mounds composed of …
Petrology And Weathering Environment Of Sub-Unconformity Limestone Unit: The Kessler Limestone Member Of The Bloyd Formation, Morrowan (Pennsylvanian) Northwest Arkansas, Thomas Daniels Dolan
Petrology And Weathering Environment Of Sub-Unconformity Limestone Unit: The Kessler Limestone Member Of The Bloyd Formation, Morrowan (Pennsylvanian) Northwest Arkansas, Thomas Daniels Dolan
Graduate Theses and Dissertations
In northwest Arkansas the thin, widespread Pennsylvanian Kessler Limestone of the Bloyd Formation is exposed in numerous locations. Comparison of various exposures shows the Kessler is heterogeneous in thickness and lithology. Thickening of the Kessler occurs southward into the Arkoma Basin where the interval has been commonly used as a horizon for natural gas exploration. The Kessler Limestone is underlain by the Dye Shale Member of the Bloyd Formation and overlain by the Trace Creek Shale of the Atoka Formation. The contact between the Kessler Limestone Member and the Trace Creek is a regional unconformity in the midcontinent, marked by …
An Investigation Of 3d Seismic Deep Basement Events In Osage County, Oklahoma, Kevin Matthew Liner
An Investigation Of 3d Seismic Deep Basement Events In Osage County, Oklahoma, Kevin Matthew Liner
Graduate Theses and Dissertations
Deep basement events seen in 3D seismic surveys located in Osage County, Oklahoma can be observed and may have affect overlying sedimentary formations. The 3D surveys used in this study are on the Chautauqua platform about fifty miles northwest of Tulsa, Oklahoma. Stratigraphy of the work area spans base of the Permian to Precambrian formations, with basement depth averaging around 5000 ft in the area of the 3D seismic surveys. Cores spanning Precambrian to Pennsylvanian were examined in the area of the 3D seismic surveys. Hydrothermal minerals were observed in Mississippian age cores. The basement events where tracked using OpendTect …
Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin
Effects Of Landscape Disturbances On Autotrophic Processes Within Arkansas Ozark Streams, Bradley J. Austin
Graduate Theses and Dissertations
Land-use change is one of the most widespread human impacts and can influence abiotic and biotic processes within surrounding streams. For example, streams in agricultural and urban watersheds receive greater light and nutrient inputs that can promote increased algal growth and primary production. Natural gas (NG) infrastructure development, a recent land use change in many regions, may also stimulate forested stream primary production, by reducing forest cover and increasing sediments and nutrient transport. I sampled streams across a NG activity gradient for algal biomass and gross primary production (GPP) to assess potential effects of this emerging land-use type. Algal biomass …
Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers
Source Constraints Of Ore Metals In Mississippi Valley-Type Deposits In Central And Eastern Tennessee Using Pb Isotopes, Austin Moyers
Graduate Theses and Dissertations
The Mississippi Valley-Type (MVT) Central and East Tennessee (TN) Districts contain economically significant lead-zinc deposits that occur in the Early Ordovician carbonates of the Knox Group. Although both districts share similar host rock, have similar temperatures of formation, and typically fill open spaces of collapse breccias or replace their host carbonates, previous studies may suggest that these ores did not form from the same mineralizing fluids and may have different Pb sources. Nu Plasma MC-ICP-MS Pb isotopic analyses on sulfides from Central and East TN were conducted and the metal sources evaluated. Results were plotted on covariation diagrams with respect …
Geologic Controls On Oil And Gas Accumulation And Production From Missourian Stage Granite Wash Reservoirs In The Western Anadarko Basin, Wheeler County, Texas, Derrell Mathis
Graduate Theses and Dissertations
Up-to-date regional and local Granite Wash data of any form is either too scarce to reference or highly privatized by exploration and production companies operating in the region. The objective of this research is to correlate horizontal production data with mapped depositional trends from Upper Pennsylvanian (Missourian Stage) Granite Wash reservoirs in the Western Anadarko Basin in northeastern Wheeler County, Texas. The correlation of raster logs to define various trap type and geometries in Missourian Granite Wash reservoirs of Wheeler County, Texas is used to understand the geologic controls on oil and gas accumulation and production. The analysis includes detailed …
Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver
Development Of A Hydrologic Model For An Urban Headwater Stream: The Influence Of Pervious Surface Properties On Runoff Dynamics, Dawn A. Farver
Graduate Theses and Dissertations
A hydrologic model was developed for the Mullins Creek (MC) catchment located on the University of Arkansas campus in Fayetteville, Arkansas. The MC catchment is a small, dynamic urban stream system with a range of land use/land cover (LULC), an extensive and well-developed stormwater drainage network, and extensive urbanization (over 90% developed, and almost 50% impervious surface area (ISA)). Selected datasets provided information on the stormwater drainage network, the physical attributes of the catchment and receiving waterway (i.e. drainage area, slope, etc.), infiltration potential of soil map units, LULC, and percent ISA. These datasets were analyzed to provide input parameters …
Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti
Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti
Graduate Theses and Dissertations
Mangrove forests are national treasures of the United Arab Emirates (UAE) and other arid countries with limited forested areas. Mangroves form a crucial part of the coastal ecosystem and provide numerous benefits to society, economy, and especially the environment. Mangrove trees, specifically Avicennia marina, are studied in their native habitat in order to characterize their population structure, aboveground biomass, and soil properties. This study focused on Eastern Mangrove Lagoon National Park in Abu Dhabi, which was the first mangrove protected area to be designated in UAE. In situ measurements were collected to estimate Avicennia marina status, mortality rate (%), …
Seeing Below The Surface With Electrical Resistivity Tomography: Exploring The Deepest Reaches Of Arkansas' Tallest Prehistoric Mounds, James Robert Zimmer-Dauphinee
Seeing Below The Surface With Electrical Resistivity Tomography: Exploring The Deepest Reaches Of Arkansas' Tallest Prehistoric Mounds, James Robert Zimmer-Dauphinee
Graduate Theses and Dissertations
Despite decades of research and over a century of public interest, the most prominent features at Toltec Mounds Archeological State Park, Mound A and Mound B, remain virtually unexamined by modern archaeological techniques, and poorly understood. The tremendous scale and importance of these mounds makes most standard research methods difficult if not impossible. Electrical Resistivity Tomography, a geophysical technique rarely used in North America, was employed to survey both Mound A and Mound B, resulting in models of the subsurface that provide insights into the construction, modification and condition of the mounds.
Are Concentration-Discharge Relations Influenced By Water Sample Collection Methods?, William M. Welch
Are Concentration-Discharge Relations Influenced By Water Sample Collection Methods?, William M. Welch
Graduate Theses and Dissertations
Two primary methods of stream water sampling, the U.S. Geologic Survey (USGS) equal-width increment (EWI) and point samples (PS) from vertical centroid of flow (VCF) were compared at three river sites, the White River near Fayetteville, Richland Creek at Goshen, and War Eagle Creek near Hindsville. A little over three years of concentration data, which was paired with corresponding instantaneous discharge values (http://ar.water.usgs.gov/), was gathered separately at each site by the Arkansas Water Resource Center (AWRC) and the United States Geological Survey (USGS). The purpose of this study was to evaluate how concentration is related to discharge when water samples …
Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley
Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley
Graduate Theses and Dissertations
Biochar, a charcoal product produced by the anaerobic thermal decomposition of biomass, can provide agronomic benefits when soil applied. However, research is lacking in temperate region soils investigating specific biochar products and their effects on agronomically important crops. A greenhouse study utilizing poultry litter biochar and a field study utilizing pine woodchip biochar were conducted to observe the effects of biochar application to Northwest Arkansas soils on corn growth and nutrient availability. A third experiment investigated poultry litter and pine woodchip biochar influences on soil water retention. In all three experiments, biochar was applied at three rates (0, 5, and …
A Hazard Assessment And Proposed Risk Index For Art, Architecture, Archive And Artifact Protection: Case Studies For Assorted International Museums, Clara Jeanene Kirk
A Hazard Assessment And Proposed Risk Index For Art, Architecture, Archive And Artifact Protection: Case Studies For Assorted International Museums, Clara Jeanene Kirk
Graduate Theses and Dissertations
This study proposes a hazard/risk index for environmental, technological, and social hazards that may threaten a museum or other place of cultural storage and accession. This index can be utilized and implemented to measure the risk at the locations of these storage facilities in relationship to their geologic, geographic, environmental, and social settings. A model case study of the 1966 flood of the Arno River and its impact on the city of Florence and the Uffizi Gallery was used as the index focus. From this focus an additional eleven museums and their related risk were assessed. Each index addressed a …
Applications Of A New Geodata Crawler For Landscape Ecology: From Mapping Natural Stream Hydrology To Monitoring Endangered Beetles, Douglas Ryan Leasure
Applications Of A New Geodata Crawler For Landscape Ecology: From Mapping Natural Stream Hydrology To Monitoring Endangered Beetles, Douglas Ryan Leasure
Graduate Theses and Dissertations
An investigation of endangered American burying beetle (Nicrophorus americanus) ecology led to development of a Geodata Crawler with applications in eco-hydrology. Geodata Crawler includes a national GIS (geospatial information systems) database with layers that quantify climate, land cover, soils, human development, and other attributes of the biosphere. For user-locations in the continental United States, Geodata Crawler can rapidly tabulate site-specific statistics within automatically delineated sample areas: points, site radii, watersheds, and riparian zones, among others. Geodata Crawler supported a multi-scale analysis of N. americanus habitat at a military installation in western Arkansas to produce a Landsat-based monitoring tool. Royle's N-mixture …
Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs
Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs
Graduate Theses and Dissertations
Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …
Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford
Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford
Graduate Theses and Dissertations
Several potential indicators of rice (Oryza sativa L.) response to nitrogen (N) fertilization include the soils alkaline hydrolyzableN (AHN) concentration, seeding date, and the soils clayfixed NH4N content. Three studies were conducted to: (1) correlate AHN, determined using Illinois Soil Nitrogen Test (ISNT) or Nitrogen Soil Test for Rice (NSTaR), to plant parameters of interest and develop a fertilizer N rate calibration curve capable of predicting the 95% relative grain yield (RGY) fertilizer N rate for rice grown on clayey soils; (2) evaluate the influence of seeding date and N fertilization on rice plant growth and grain …