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Completion Report: Pesticide And Nitrate Monitoring Results For Craighead, Mississippi, And Poinsett Counties, Arkansas: Phase Ii, Kenneth F. Steele, William R. Clayton, Terry W. Nichols, Paul F. Vendrell Jun 1993

Completion Report: Pesticide And Nitrate Monitoring Results For Craighead, Mississippi, And Poinsett Counties, Arkansas: Phase Ii, Kenneth F. Steele, William R. Clayton, Terry W. Nichols, Paul F. Vendrell

Arkansas Water Resources Center Technical Reports

Because of the concern for potential contamination of ground water by agricultural chemicals, 38 wells drilled in the Mississippi River Valley alluvial aquifer in Mississippi County and the eastern parts of Craighead and Poinsett Counties, Arkansas were analyzed for pesticides and nitrate. The pesticide, fluometuron, was detected in one sample at a concentration of 0.5 mg/L. Bentazon was detected in three samples at concentrations of 2.5, 0.3, and 0.3 mg/L. The occurrences of the pesticides appear to represent isolated incidents rather than a widespread aquifer contamination. All detections were below health and safety standards. Nitrate is present in several wells …


Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer Jun 1993

Acoustic Properties Of Fine‐Grained Sediments From Emerald Basin: Toward An Inversion For Physical Properties Using The Biot–Stoll Model, Robert C. Courtney, Larry A. Mayer

Affiliate Scholarship

Acoustic data from two long cores, comprising marine clays and silts taken from Emerald Basin off Nova Scotia, are presented. High‐resolution measurements of compressional wavevelocity,attenuation, and power law exponent are made using ultrasonic frequencies between 100 to 1000 kHz. The observed values of the frequency dependence of attenuation suggest that a nonconstant Q mechanism is needed to explain these data, and Biot–Stoll theory is used to model the experimental results. An inversion scheme is used to constrain physical parameters in the Biot–Stoll dispersion relation. The inversion shows that there is a restricted range of permeability and grain size. By assigning …


Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards Jun 1993

Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards

Arkansas Water Resources Center Technical Reports

In Arkansas, much of the environmental concern related to water quality has focused on the high volume of poultry fecal waste spread on the surf ace of local pastures to fertilize forage grass. Cyromazine (N-cyclopropyl-1,3,5-triazine-2,4,6- triamine), a feed-through larvicide used to control house flies (Musca domestica), is often a component of caged-layer manure. Cyromazine is quite soluble and stable in water, and previous research has shown that it can be readily washed from pasture plots by intense rainfall. Therefore, a study was conducted to evaluate increased drying time as a best management practice technique for reducing cyromazine runoff losses from …


Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel Jun 1993

Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel

Arkansas Water Resources Center Technical Reports

Runoff and water quality data collected from two pairs of grazed fields in northwestern Arkansas were analyzed to support efforts to model runoff quality from areas receiving poultry manure and other fertilizer sources. The monitoring period described in this report was September 1, 1991 to April 30, 1993. One of each pair of fields was fertilized with inorganic fertilizer, and the other received either poultry litter or manure. Losses of fertilizer constituents were quite low from an agronomic standpoint, ranging from approximately 2-11 kg N/ha/year and 0.5-4.1 kg P04-P/ha/year. Annual losses of fertilizer constituents were dominated by only a small …


Diet And Feeding Habits Of The Southern Stingray Dasyatis Americana In The Central Bahamas, David S. Gilliam, K. M. Sullivan May 1993

Diet And Feeding Habits Of The Southern Stingray Dasyatis Americana In The Central Bahamas, David S. Gilliam, K. M. Sullivan

Marine & Environmental Sciences Faculty Articles

No abstract provided.


An Alternative Representation Of The Ice Canopy For Calculating Microwave Brightness Temperatures Over A Thunderstorm, Bradley M. Muller, Henry E. Fuelberg, Eric A. Smith May 1993

An Alternative Representation Of The Ice Canopy For Calculating Microwave Brightness Temperatures Over A Thunderstorm, Bradley M. Muller, Henry E. Fuelberg, Eric A. Smith

Publications

Passive microwave brightness temperatures (T(B)'s) at 92 and 183 GHz from an aircraft thunderstorm overflight are compared with values calculated from radar-derived hydrometeor profiles and a modified proximity sounding. Two methods for modeling particles in the ice canopy are contrasted. The first is a ''traditional'' approach employing Marshall-Palmer ice spheres. The second, or ''alternative,'' method partitions 20% of the ice water content into a Marshall-Palmer component for graupel and hail, and 80% into a modified gamma spherical particle size distribution function representing ice crystals.

Results from the alternative approach are superior to those from the traditional method in the anvil …


Focus On Phosphorus: Arkansas Water Resources Center Research Conference, Kenneth F. Steele Apr 1993

Focus On Phosphorus: Arkansas Water Resources Center Research Conference, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

No abstract provided.


Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood Apr 1993

Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood

OES Theses and Dissertations

This study tested the validity of using intraspecific variation in benthic foraminifera as a means for determining Pleistocene paleobathymetry. Canonical variate analysis was used as a means for determining visually undetectable but statistically significant differences in the morphology of selected species. Two species, Cassidulina subglobosa and Uvigerina peregrina, were collected from Pleistocene well cuttings from the northwest Gulf of Mexico. The canonical analysis involved comparing the intraspecific variation of these Pleistocene species to their counterparts occurring in the modern Gulf of Mexico, where intraspecific variation was previously analyzed and found to be sufficient to allow detection of bathymetric differences …


The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery Apr 1993

The Biogeochemistry Of Hydrogen Sulfide In The Open Ocean, Joël Radford-Knoery

OES Theses and Dissertations

Hydrogen sulfide is a poorly quantified component of the global sulfur cycle. In seawater, its dissolved species (dissolved sulfide) can react with trace metals to form dissolved complexes and insoluble compounds. Therefore, the study of dissolved° sulfide in the open ocean can yield a better understanding of the biogeochemical cycles of sulfur and trace metals.

The biogeochemical cycling of dissolved sulfide was examined using specially developed sampling and analytical methods. In the western North Atlantic and central Equatorial Pacific Oceans, total dissolved sulfide concentrations ranged from /L; they were highest, in the mixed layer and decreased with depth. The depth …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan Apr 1993

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan

OES Theses and Dissertations

Two time- and space-dependent, physical-bio-optical models have been developed for the California Coastal Transition Zone (CTZ) region with the overall objective of understanding and quantifying the processes th at contribute to the spatial and temporal development of nutrient and plankton distributions in the CTZ. The first of these models considers only time- and vertical processes at specific locations in the CTZ. The model food web components include: silicate, nitrate, ammonium, two phytoplankton size fractions, copepods, doliolids, euphausiids and a detritus pool. The wavelength dependent attenuation of the subsurface irradiance field, due to sea water, phytoplankton pigment concentrations and dissolved organic …


Characterization Of Laboratory Generated Turbulence By Optical Phase Measurements, Eric P. Magee Mar 1993

Characterization Of Laboratory Generated Turbulence By Optical Phase Measurements, Eric P. Magee

Theses and Dissertations

The resolution achieved by an optical imaging system in the presence of the random effects of the atmosphere is severely degraded from the theoretical diffraction limit. Techniques exist for recovering near diffraction limited performance of an imaging system in the presence of atmospheric turbulence. As opposed to laboratory testing, testing image enhancement techniques in the Earth's atmosphere imposes many limitations. Unfavorable weather conditions could result in the loss of time and money invested in conducting the experiments. With a properly characterized turbulence generator, with statistics that match those of the atmosphere, experimental testing of image enhancement techniques can be conducted …


Including Maximum Sustained Wind Speed In A Time Series Model To Forecast Hurricane Movement, Timothy B. Mott Mar 1993

Including Maximum Sustained Wind Speed In A Time Series Model To Forecast Hurricane Movement, Timothy B. Mott

Theses and Dissertations

Techniques for applying time series fundamentals to forecasting hurricane movement are thoroughly examined in this research. The objectives are: (1) to modify Dr. Thomas Curry's threshold autoregressive time series model to improve its ability to forecast hurricane movement, (2) to forecast the maximum sustained wind speed for a hurricane, and (3) to identify if wind speed should be included as an explanatory variable to aid in forecasting hurricane movement. Eleven different models to predict the latitude, longitude and maximum sustained wind speed are compared and contrasted with Curry's bivariate time series model. The results showed the modifications allow significant forecasting …


Applications Of Gaming Techniques To Coastal Zone Problems, Robert Adam Drews Feb 1993

Applications Of Gaming Techniques To Coastal Zone Problems, Robert Adam Drews

Marine Affairs Theses and Major Papers

The boundary between sea and land is an area which presents enormous management challenges. It is an area of fragile ecology, dense and growing population, multiple competing demands for resource use, a multitude of regulatory agencies, and far from complete scientific understanding. Given these difficulties, planning for coastal zone management frequently suffers from incomplete data, lack of consensus among users, and lack of support from government authorities. This paper proposes gaming as a tool for assisting in the information gathering, education, consensus building, and communications elements of planning. This is achieved by developing a planning game which is designed to …


Emergence Periodicity Of Caretta Caretta In Broward County, Florida, 1990, William E. Margolis, Curtis M. Burney Feb 1993

Emergence Periodicity Of Caretta Caretta In Broward County, Florida, 1990, William E. Margolis, Curtis M. Burney

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.


Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer Feb 1993

Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer

Affiliate Scholarship

This paper presents the filter correlation method, a technique for extracting consistent and accurate estimates of attenuation parameters from acoustic waveform data. The method minimizes problems associated with short time windows and multipath secondary arrivals. The method comprises two stages: a causal passband filter stage followed by a cross-correlation step. The results of the filter-correlation estimator are compared to those of the spectral difference approach for short time series with and without a secondary multipath arrival. Preliminary analyses of acoustic data collected on cored marine silts and clays show the attenuation properties of these materials cannot be described by a …


Trends In The Spatial Distribution Of Sea Turtle Activity On An Urban Beach (1981-1992), Catherine A. Mattison, Curtis M. Burney, Louis Fisher Feb 1993

Trends In The Spatial Distribution Of Sea Turtle Activity On An Urban Beach (1981-1992), Catherine A. Mattison, Curtis M. Burney, Louis Fisher

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.


Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner Jan 1993

Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner

Faculty Publications

Annual carbon, nitrogen, and phosphorus leachate rates from live Spartina alterniflora Loisel in a Louisiana (USA) salt marsh were estimated to be 200, 14, and 3 g m-2, respectively, and to peak in summer and higher salinit~es. Leachate losses of P, N and C are equivalent to a turnover of live plant tissues of 10, 17 and 49 d, respectively, when submerged, and 148, 250 and 721 d, respectively, when unsubmerged. Plant leachate losses during marsh submergence and non-submergence are nearly equal because release rates are 15x greater during submergence. Nitrogen and carbon concentrations relative to phosphorus are proportionately 4x …


Master's Degree Programs In Marine Biology And Coastal Zone Management 1993, Nova University Jan 1993

Master's Degree Programs In Marine Biology And Coastal Zone Management 1993, Nova University

Halmos College of Natural Sciences and Oceanography Course Catalogs

No abstract provided.


Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle Jan 1993

Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle

Affiliate Scholarship

The Ontong Java Plateau, a large, deep-water carbonate plateau in the western equatorial Pacific, is an ideal location for studying responses of carbonate sedimentation to the effects of changing paleoceanographic conditions. These carbonate responses are often reflected in the physical properties of the sediment, which in turn control the appearance of seismic reflection profiles. Seismic stratigraphy analyses, correlating eight reflector horizons to each drill site, have been conducted in an attempt to map stratigraphic data. Accurate correlation of seismic stratigraphic data to drilling results requires conversion of traveltime to depth in meters. Synthetic seismogram models, using shipboard physical properties data, …


Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher Jan 1993

Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher

Affiliate Scholarship

During Ocean Drilling Program Leg 130, sonic velocity and bulk density/porosity well logs were measured in five separate holes drilled through the sequence of pelagic carbonate oozes, chalks, and limestones that comprise the thick, continuous sedimentary cover on the Ontong Java Plateau. An internally consistent and continuous suite of shipboard laboratory velocity and sediment physical properties measurements were made from the top of each hole down through the entire logged interval. Because of the high quality of the data, extensive overlap of 500 m or more between the log and laboratory measurements at each hole, and the homogeneous nature of …


Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens Jan 1993

Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens

Affiliate Scholarship

Based on index properties measurements made on board the JOIDES Resolution, we studied porosity changes with depth in the fairly homogeneous deep-sea calcareous sediments cored during Ocean Drilling Program Leg 130 on the Ontong Java Plateau. Using Leg 130 data, we present evidence that the rate of porosity decrease with burial in calcareous oozes and chalks is related to the depth of deposition and thus probably depends on the "conditioning" of calcareous sediments by winnowing or dissolution processes during the time of deposition. The ooze-to-chalk transition is not clearly reflected in porosity profiles. In the ooze-chalk sections studied (the upper …


Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama Jan 1993

Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama

Affiliate Scholarship

We used the continuous saturated bulk density records collected by the gamma-ray attenuation porosity evaluator (GRAPE) at Ocean Drilling Program Site 806 on the top of the Ontong Java Plateau to evaluate the continuity of the recovered cores and to splice together a complete section from the multiple holes drilled at the site (for the upper 165 m, this is equivalent to approximately 0-5 Ma). The lack of offset in core breaks (between the 9.5-m-long, successive cores) from hole to hole made splicing difficult, and the results are not unambiguous. The composite section was converted to a time series by …


Modeling Trihalomethane Formation In Bromide-Containing Surface Water Undergoing Conventional Treatment, Maureen Mcbride Smith Jan 1993

Modeling Trihalomethane Formation In Bromide-Containing Surface Water Undergoing Conventional Treatment, Maureen Mcbride Smith

Theses Digitization Project

No abstract provided.


Effects Of Domestic Wastewater Effluent On The Water Quality And Aquatic Macroinvertebrates In A Sharp County, Arkansas Stream, Linda E. Moss, George L. Harp Jan 1993

Effects Of Domestic Wastewater Effluent On The Water Quality And Aquatic Macroinvertebrates In A Sharp County, Arkansas Stream, Linda E. Moss, George L. Harp

Journal of the Arkansas Academy of Science

The purpose of this study was to determine whether the effluent of the Ash Flat Wastewater Treatment Plant changes the water quality or aquatic macroinvertebrate community structure of North Big Creek. Weekly water samples were analyzed for pH, N, P, COD, TSS and fecal coliform bacteria from 17 June to 19 August 1992. Aquatic macroinvertebrates were collected biweekly using a Turtox Indestructible™ Dip Net, and density indices were calculated. Station 1, above the effluent, was a spring habitat. Fecal coliform, N, P, TSS and COD values were higher at this station, while the aquatic macroinvertebrate community was relatively simple. The …


Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama Jan 1993

Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama

Affiliate Scholarship

A detailed Pliocene oxygen isotope record from the Ontong Java Plateau, based on measurements of the surface-dwelling planktonic foraminifer Globigerinoides sacculifer, was produced for the period from 5 to 2 Ma. The record documents major long and short-term climate changes. The results show periods of enhanced ice volume at 4.6 to 4.3 Ma and after 2.85 Ma, a long-term warming trend from 4.1 to 3.7 Ma, and a distinct cooling trend that was initiated at 3.5 Ma and progressed through the initiation of large-scale Northern Hemisphere glaciation after 2.85 Ma (according to the time scale of Shackleton and others proposed …


Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer Jan 1993

Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer

Affiliate Scholarship

We used well logs, in some cases combined with shipboard physical properties measurements to make more complete profiles and to correlate between sites on the Ontong Java Plateau. By comparing sediment bulk density, velocity, and resistivity logs from adjacent holes at the same site, we showed that even subtle features of the well logs are reproducible and are caused by variations in sedimentation. With only minor amounts of biostratigraphic information, we could readily correlate these sedimentary features across the entire top of the Ontong Java Plateau, demonstrating that for most of the Neogene the top of the plateau is a …


Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens Jan 1993

Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens

Affiliate Scholarship

During Leg 130, an intensive program of P-wave velocity measurements was conducted on calcareous sediments of varying induration (ranging from ooze to limestone) that cover the Ontong Java Plateau (west equatorial Pacific). The high quantity and quality of shipboard acoustical property measurements seemed to be particularly appropriate for gaining a better understanding of acoustic anisotropy in calcareous sediments. Major results can be summarized as follows: 1. In calcareous oozes, acoustic anisotropy exists even at shallow depths of burial. Values are low, ranging from -0.5% to 3.5% and averaging 1.2%. Anisotropy profiles are affected by coring disturbances, but they still roughly …


Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer Jan 1993

Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer

Affiliate Scholarship

Site surveys conducted in conjunction with Leg 130 on the Ontong Java Plateau reveal a strong seismic reflector at 0.8 to 1.0 s below the seafloor that drilling at Sites 803 and 807 confirmed is Cretaceous basalt. This reflector is generally smooth, except for the northeastern margin of the plateau, where it forms a series of small, irregularly shaped depressions. Correlatable reflectors present at the bottom of the depressions are also present on the adjacent highs, suggesting that these depressions are original volcanic topography. A strong sub-basalt reflector occurs on many seismic profiles on the northeastern portion of the plateau. …


Ichthyofauna Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves Jan 1993

Ichthyofauna Of A Cypress-Tupelo Swamp, Veryl V. Board, Charlotte Allen, Andrea Reeves

Journal of the Arkansas Academy of Science

No abstract provided.


Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project, Terry Nichols, Paul Vendrell, Kenneth Steele Jan 1993

Completion Report: Arkansas State Pesticides In Ground Water Monitoring Project, Terry Nichols, Paul Vendrell, Kenneth Steele

Arkansas Water Resources Center Technical Reports

Executive Summary. The Arkansas State Plant Board (ASPB) has completed a monitoring project in Ashley County, Arkansas. Twenty-nine samples from 23 wells were analyzed for 10 pesticides commonly used in Ashley County. The only detection was Metolachlor, at 0. 71 ug/L, in one well. When the well was subsequently resampled no pesticides were detected. Fifteen of the wells were also tested for nitrate. In one of the wells nitrate was measured at 10.3 mg/L. The other wells were all below 0.05 mg/L. Extensive quality assurance (QA) data collected during the project indicate that 94% of the pesticide data meet all …