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Correlating Soil Test Phosphorus Losses In Runoff, D. H. Pote, T. C. Daniel, P. A. Moore Jr., D. J. Nichols, D. R. Edwards, A. N. Sharpley Jun 1994

Correlating Soil Test Phosphorus Losses In Runoff, D. H. Pote, T. C. Daniel, P. A. Moore Jr., D. J. Nichols, D. R. Edwards, A. N. Sharpley

Arkansas Water Resources Center Technical Reports

Phosphorus in agricultural runoff is often a major cause of accelerated eutrophication of lakes and streams. Previous research has indicated that the amount of dissolved P (DP) in runoff is directly related to P content of the surface soil. Decades of fertilizer application at rates exceeding those of crop uptake have elevated soil test P (STP) levels in areas of intensive crop and livestock production, making this the major source of DP loss in runoff. The objective of our experiment was to relate STP content of Captina silt loam to P concentration and loss in runoff, and determine which STP …

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Assessment Of Effectiveness Of Buffer Zones In Removing Impurites In Runoff From Areas Treated With Poultry Litter, I. Chaubey, D. R. Edwards, T. C. Daniels Jun 1994

Assessment Of Effectiveness Of Buffer Zones In Removing Impurites In Runoff From Areas Treated With Poultry Litter, I. Chaubey, D. R. Edwards, T. C. Daniels

Arkansas Water Resources Center Technical Reports

Land application of animal manures (e.g. poultry litter, poultry manure, and swine manure) to pasture and range can lead to runoff quality degradation during storms that occur soon after application. Vegetative filter strips (VFS) have been shown to reduce pollution in runoff from row-cropped areas but have not been extensively studied in pasture and range settings. This research involved characterizing performance of fescue VFS in improving quality of runoff from pasture land areas treated with poultry litter and swine manure. The VFS were found to be quite effective in reducing off-site transport of ammonia nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), …

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Arkansas Rice Research Studies 1993, B. R. Wells Jun 1994

Arkansas Rice Research Studies 1993, B. R. Wells

Arkansas Agricultural Experiment Station Research Series

The research reports in this publication represent one year of results; therefore, these results should not be used as a basis for longterm recommendations. Several research reports in this publication dealing with soU fertility also appear in Arkansas Soil Fertility Studies 1993, Arkansas Agricultural Experiment Station Research Series 436. This duplication is the result of the overlap in research coverage between the two series and our effort to inform Arkansas rice producers of all the research being conducted with funds from the rice check-off.

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Books And Letters Vol. 8, No.1, University Libraries, John A. Harrison, Anne Marie Candido, Michael J. Dabrishus, Juana R. Young, Ethel C. Simpson, Kim Allen Scott, Donald W. Batson Apr 1994

Books And Letters Vol. 8, No.1, University Libraries, John A. Harrison, Anne Marie Candido, Michael J. Dabrishus, Juana R. Young, Ethel C. Simpson, Kim Allen Scott, Donald W. Batson

Books and Letters

Who Selects the Books?; Director's Column; Newspaper Project Closes; Chinese Student Visits Collections

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Application Of Machine Learning Principles To Modeling Of Nonlinear Dynamic Systems, Murray R. Clark Jan 1994

Application Of Machine Learning Principles To Modeling Of Nonlinear Dynamic Systems, Murray R. Clark

Journal of the Arkansas Academy of Science

A method for the development of mathematical models for dynamic systems with arbitrary nonlinearities from measured data is described. The method involves the use of neural networks as embedded processors in dynamic system simulation models. The technique is demonstrated through generation of models for anharmonic oscillators described by the Duffing Equation and the Van der Pol Equation from measured input/output data. It is shown that high quality models of these systems can be developed using this technique which are efficient in terms of model size. Using neural networks as embedded processors, accurate models of the Duffing Oscillator and the Van …

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Ground Water Monitoring Project For Arkansas, Phase Iii, Kenneth F. Steele, Steven S. Hill, Terry W. Nichols, H. Don Scott, Paul Vendrell, H. S. Lin Jan 1994

Ground Water Monitoring Project For Arkansas, Phase Iii, Kenneth F. Steele, Steven S. Hill, Terry W. Nichols, H. Don Scott, Paul Vendrell, H. S. Lin

Arkansas Water Resources Center Technical Reports

This report is composed of two parts. The first part is an interpretation of the pesticide and nitrate data collected in Woodruff County based on samples collected during 1994. Because there is an indication that there were hydrological differences between 1994 and 1995, and because most of the pesticide data is from 1994, this interpretive portion is restricted to 1994 data. Six wells initially sampled in 1994 that contained pesticides had continuing contamination in re-sampling in 1994 and 1995. Part II lists a seventh well in Woodruff County that contained pesticides in February and May of 1995

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Compton Scattering Of Gamma-Rays From Electrons In Advanced Laboratory, Christine A. Byrd, Morgan T. Burks, Lawrence A. Yates, Wilfred J. Braithwaite Jan 1994

Compton Scattering Of Gamma-Rays From Electrons In Advanced Laboratory, Christine A. Byrd, Morgan T. Burks, Lawrence A. Yates, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

A kinematically-complete 2-body final state measurement of Compton scattering of 662-keV photons is presened, where both scattered photon energy and electron recoil energy are measured versus photon scattering angle, theta gamma. Passive collimation of the photon beam is avoided; each recoiling electron triggers a photon-scattering event providing active beam collimation. Recoiling electrons have low energies at small theta gamma, impairing electron detection efficiency. Examining the recoiling-electron energy spectra in coincidence with high-resolution gammas indicates a 1"x 1"NaI detector is superior to a 1"x1" NE-102 plastic scintillator as the active scattering material, for efficient recoil-electron detection. Electron efficiencies versus theta gamma …

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Storm Dominated Channel Sequences On A Shallow Marine Shelf: Morrowan Of Northwest Arkansas, Kimberley R. Jones, Doy L. Zachry Jan 1994

Storm Dominated Channel Sequences On A Shallow Marine Shelf: Morrowan Of Northwest Arkansas, Kimberley R. Jones, Doy L. Zachry

Journal of the Arkansas Academy of Science

The Brentwood Member of the Bloyd Formation (Morrowan, Pennsylvanian) in northwestern Arkansas contains stratigraphic sequences deposted by tropical storms in middle shelf environments. The deposits are confined to shallow channels incised by strong unidirectional currents into an interval of shale deposited during fair weather conditions. Complete storm sequences reflect initial bottom currents of high competency that declined through time and were succeeded by wave generated oscillatory activity. The storm succession consists of an erosion surface followed by a basal pebble conglomerate, massive grainstone and packstone, whole-fossil wackestone, hummocky cross-strata and a swell lag of platy crinoidcalyxes. As storm activity ceased, …

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Fluid Dynamics Model Of Data Acquisition And Date Analysis For High-Energy Physics, Charles M. Byrd, Christine A. Byrd, Wilson H. Howe, W. J. Braithwaite Jan 1994

Fluid Dynamics Model Of Data Acquisition And Date Analysis For High-Energy Physics, Charles M. Byrd, Christine A. Byrd, Wilson H. Howe, W. J. Braithwaite

Journal of the Arkansas Academy of Science

No abstract provided.

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Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan Jan 1994

Effective, Reliable, Inexpensive Cryofixation Device, Lawrence A. Mink, Roger A. Buchanan

Journal of the Arkansas Academy of Science

No abstract provided.

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Publication Policies And Suggestions For Authors, Academy Editors Jan 1994

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Analysis Of Ammunition By X-Ray Fluorescence, Michael W. Rapp, Teddy L. Townsend Jan 1994

Analysis Of Ammunition By X-Ray Fluorescence, Michael W. Rapp, Teddy L. Townsend

Journal of the Arkansas Academy of Science

Nondestructive analysis of lead shotgun pellets by X-ray fluorescence (XRF) shows considerable promise in assignment of the identity of the ammunition source. X-ray fluorescence spectra of various shotgun pellets and of standard alloys were obtained using an energy-dispersive instrument and an Am-241 source. The correlation obtained between the precent antimony in the standard alloys and the intensity of the Ka fluorescence peak from antimony was excellent. Peak areas from antimony in shotgun pellets were measured and compared to calibration plots from the standard alloys. The method was capable of distinguishing among lead-based alloys, such as ammunition, with antimony content as …

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78th Annual Meeting, 1994. Secretary's Report And Financial Statement, Academy Editors Jan 1994

78th Annual Meeting, 1994. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Computational Fluid Dynamics In Small Airway Models Of The Human Lung, G. Burnside, J. R. Hammersley, Rama N. Reddy, B. Catlin Jan 1994

Computational Fluid Dynamics In Small Airway Models Of The Human Lung, G. Burnside, J. R. Hammersley, Rama N. Reddy, B. Catlin

Journal of the Arkansas Academy of Science

The promise of gene replacement therapy for cystic fibrosis, the administration of drugs via inhalation therapy, and die deposition location of man-made airborne particulates all involve a more complete understanding of the fluid dynamics in the human lung. Flow in the larger airways may be measured through life-sized models directly, but the airways in the peripheral lung are too small and the flows are too complex to be studied in this manner. Computational models can be developed which will accurately represent both the geometric nature of the central airways and the fluid dynamics with in them. Two-dimensional and three-dimensional models …

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Proceedings Of The Arkansas Academy Of Science - Volume 48 1994, Academy Editors Jan 1994

Proceedings Of The Arkansas Academy Of Science - Volume 48 1994, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Using The Cern Program-Library Graphics And Interactive Data Display, Morgan T. Burks, Wilson H. Howe, Christine A. Byrd, Wilfred J. Braithwaite Jan 1994

Using The Cern Program-Library Graphics And Interactive Data Display, Morgan T. Burks, Wilson H. Howe, Christine A. Byrd, Wilfred J. Braithwaite

Journal of the Arkansas Academy of Science

Small scale Monte Carlo programming is growing rapidly due to the ease with which complex problems may be formulated by any programmer. These programmers may choose to exploit graphics and interactive displays available in the program library developed and maintained by CERN (the Center for European Nuclear Research). This paper outlines the use of graphics and interactive data display features of the CERN program library, developed for visualizing simulated data events in particle detectors. One example uses GEANT, CERN's Monte Carlo modeling program, to simulate 300 MeV/c protons incident on a silicon slab. Display packages for GEANT are available both …

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Reaction Of Titanocene Dichloride With Acetylenedicarboxylate, Tanya L. Hagler, Mark Draganjac, Paul M. Nave, J. Ed Bennett, Farooq Kahn, Robert Engelken, Gerard Williams, Chris Poole, Kwok Fai Yu Jan 1994

Reaction Of Titanocene Dichloride With Acetylenedicarboxylate, Tanya L. Hagler, Mark Draganjac, Paul M. Nave, J. Ed Bennett, Farooq Kahn, Robert Engelken, Gerard Williams, Chris Poole, Kwok Fai Yu

Journal of the Arkansas Academy of Science

The reaction of Cp2TiCl2 with either the mono- or dipotassium salt of acetylenedicarboxylic acid (ADC) gives high yields of an insoluble orange product. The insoluble compound shows potential semiconductor behavior, as evidenced by an apparent bandgap in the orange region of the visible spectrum. Under N2 ,the compound decomposes at 238° C, eventually losing approximately 46% total mass up to 1350° C. The exothermic decomposition in air, beginning at 235° C, results in the formation of titanium oxides.

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Boron Phosphate And Aluminum Phosphate Aerogels, David A. Lindquist, Steven M. Poindexter, Sterling S. Rooke, D. Ritchie Stockdale, Kirk B. Babb, Alison L. Smoot, William E. Young Jan 1994

Boron Phosphate And Aluminum Phosphate Aerogels, David A. Lindquist, Steven M. Poindexter, Sterling S. Rooke, D. Ritchie Stockdale, Kirk B. Babb, Alison L. Smoot, William E. Young

Journal of the Arkansas Academy of Science

Anhydrous sol-gel condensation of triethyl phosphate [(CH3CH2O)3PO] with boron trichloride (BCL3 ) or triethyl aluminum [(CH3CH2 ) 3A1] in organic solvents, led to formation of metallophosphate gels. The pore fluid of the gels was removed under supercritical conditions in a pressurized vessel to form aerogels. The aerogels were then calcined at progressively higher temperatures to produce high surface area phosphates. Since the initial gel reagent mixtures contained several NMR active nuclei, the condensation chemistry prior to the gel point was monitored by solution nB NMR. The surface areas, distribution of pore sizes, and total pore volumes of the aerogel products …

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Visualizing Electrostatic Phenomena Using Mathematica, Eric Mayes Jan 1994

Visualizing Electrostatic Phenomena Using Mathematica, Eric Mayes

Journal of the Arkansas Academy of Science

A set of packages for visualizing electrostatic phenomena was developed using Mathematica as a programming language. These packages allow users to plot potential fields, equipotential lines, 2-D and 3-D vector fields in order to gain a visual understanding of electrostatic charges. They would be useful in accompanying undergraduate physics labs pertaining to electrostatics, as they would enable students to connect experiment with mathematics through open-ended visual exploration

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Hammett Correlations Of Half-Wave Reduction Potentials In A Series Of N-(Aryl Substituted)-Dichloronicotinamides, Cecil C. Persons, Ali U. Shaikh, Julie Shiflett, Frank L. Setliff Jan 1994

Hammett Correlations Of Half-Wave Reduction Potentials In A Series Of N-(Aryl Substituted)-Dichloronicotinamides, Cecil C. Persons, Ali U. Shaikh, Julie Shiflett, Frank L. Setliff

Journal of the Arkansas Academy of Science

Excellent correlations of Hammett substituent constants (sigmaR) of a series of N-(R-substituted aryl) -2,6-, 2,5-, and 5,6- dichloronicotinamides with polarographic half-wave potentials were observed. Although the correlations demonstrate that all three series of amides experience comparable sensitivity to the R groups at the carbonyl reduction site, the relative ease of reduction varies according to the chlorine substitution pattern on the pyridine ring. These differences are suggested to be due to combinations of mesomeric, inductive, and field effects which operate differently in the three systems. Correlation analysis also revealed that Hammett heteroatomic replacement constants previously determined by NMR studies are valid …

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Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac Jan 1994

Thermal Decomposition Studies Of Selected Transition Metal Polysulfide Complexes. Ii. Effect Of Atmosphere On Decomposition, Benjamin Rougeau, Mark Draganjac

Journal of the Arkansas Academy of Science

Initial studies involved the thermal decomposition profile of five polysulfide complexes in air up to 550 °C. Since our first report to the Academy in 1990, we have obtained the capability to run samples up to 1500°C under various gases. Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA)of a series of transition metal polysulfide complexes are presented. Compounds analyzed included Cp2TiS5 ,MoS9 2",MoOS8 2", Zn(S x ) 2", Cd(S x ) 2-, Fe2S122 - and NiS82.

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Aquatic Macrophytes Of Two Small Northwest Arkansas Reservoirs, John J. Sullivan, Arthur V. Brown Jan 1994

Aquatic Macrophytes Of Two Small Northwest Arkansas Reservoirs, John J. Sullivan, Arthur V. Brown

Journal of the Arkansas Academy of Science

Lake Fayetteville and Lake Wedington are small reservoirs of about the same size and age that are located in northwestern Arkansas. We collected macrophytes from eleven transects around each reservoir in the autumn of 1993. Justicia (waterwillow), Typha (cat-tail), Scirpus (bulrush), Potamogeton (pondweed), and Zannichellia (horned pondweed) occur in both reservoirs. Justicia occurs most commonly in both reservoirs. The macrophytes of Lake Wedington are organized in a characteristic zonation pattern with bands from shore toward open water of emergent, floating-leaved, then submersed macrophytes. Macrophyte zonation was not as evident in Lake Fayetteville because of the low occurrence of floating leaved …

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Monte Carlo Simulation Of The Scintillating Optical Fiber Calorimeter (Sofcal), Zibin Yang, Russell Gillum, Donald C. Wold Jan 1994

Monte Carlo Simulation Of The Scintillating Optical Fiber Calorimeter (Sofcal), Zibin Yang, Russell Gillum, Donald C. Wold

Journal of the Arkansas Academy of Science

A scintillating optical fiber calorimeter (SOFCAL) is being developed by NASA/Marshall Space Flight Center for use in balloon-borne emulsion chambers to study the spectrum of high-energy cosmic rays and gamma rays. SOFCAL will not saturate for long exposures, and the detector will be helpful for the study of primary cosmic-ray nuclei energies from 100 GeV to 1,000 TeV. For a given incident particle and energy, computer simulations of electromagnetic cascades allow computation of energy deposited in different regions of the calorimeter. For these initial simulations, a 5-cm x 5-cm x 7-cm calorimeter was used. Each subsection contained a 0.4-cm thick …

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Ultrasound Assisted Oxidative Cleavage Of Alpha-Keto, Alpha-Hydroxy And Alpha-Halo Ketones By Superoxide, Yi Hong Cao, A. Toland, Dominic T.C. Yang Jan 1994

Ultrasound Assisted Oxidative Cleavage Of Alpha-Keto, Alpha-Hydroxy And Alpha-Halo Ketones By Superoxide, Yi Hong Cao, A. Toland, Dominic T.C. Yang

Journal of the Arkansas Academy of Science

No abstract provided.

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Directory Of Water Resource Experts At Arkansas Universities And Colleges, Kenneth F. Steele Dec 1993

Directory Of Water Resource Experts At Arkansas Universities And Colleges, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

The objective of this publication is to identify those faculty and staff scientists in the universities and colleges of Arkansas who are actively conducting research on water resource issues and problems. Undoubtedly, we have omitted several such researchers, but hopefully, a second edition of this publication will be more complete.

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Arkanasas Water Resources Center Evaluation Report Fy 1988-Fy 1992, Kenneth F. Steele Aug 1993

Arkanasas Water Resources Center Evaluation Report Fy 1988-Fy 1992, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

Since the beginning of the Arkansas Water Resources Center the overall program has been focused on helping local, state and federal agencies learn to manage Arkansas' water resources. AWRC has contributed substantially to the State's water resources via research and training of students. Through the years, projects have included topics concerned with irrigation, ground water modeling, non-point source pollution (including sediment erosion), water quality, efficient septic tank design, and ecosystems. Information on water research and other water-resource information is disseminated by the Center through public presentations, conferences, and publications. Since 1980, an average of more than 15 principal investigators a …

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Determination Of The Efficacy Of Fertilization Practices On Bob Kidd Lake, Richard L. Meyer, Jeanette K. Shipley-Phillips Jun 1993

Determination Of The Efficacy Of Fertilization Practices On Bob Kidd Lake, Richard L. Meyer, Jeanette K. Shipley-Phillips

Arkansas Water Resources Center Technical Reports

Fertilization strategies have been used as a standard practice on Bob Kidd and other lakes and reservoirs to enhance the availability of phytoplankton and zooplankton as food sources for developing fish. The nominal practice is to use a fixed application rate and a constant ratio of nitrogen and phosphorus fertilizer per acre of lake surface. The application technique varies as does the timing. Application techniques vary from spillage and bulk deposition of fertilizer at selected sites to broadcasting of pellets or a pre-mixed slurry via boat and/or airplane. Timing is usually in the spring under appropriate weather conditions.

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Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells Jun 1993

Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells

Arkansas Water Resources Center Technical Reports

Current perception is that nutrient runoff from croplands is a significant contributor to poor water quality in some areas. While extensive research has been conducted to survey and ameliorate this problem for several upland crops, little work has been done to evaluate the problem with flooded rice (Oryza sativa, L.) soils. Since rice production utilizes a major portion of the total irrigation water usage for certain areas, it is important to understand the contribution of rice production to non-point source N and P in surface water. Several production fields were selected to evaluate the concentrations of nutrients in the floodwater …

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The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost Jun 1993

The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost

Arkansas Water Resources Center Technical Reports

The research protocol was designed to compare three reservoirs with similar physical environments but different morphometry. Three reservoirs on the western edge of the Ozark uplift were selected because of their similar substrate and climatic condition. The reservoirs primarily differed in morphometry. Two of the reservoirs were of identical size, Bob Kidd and Prairie Groves Lakes, but of different configuration, semicircular and linear, respectively. The bifurcated lake, Lincoln Lake, was of smaller size. Each lake is dimictic. Each of the lakes were nitrate-N limited while soluble reactive phosphorus-P is available and not restricting the growth of phytoplankton. Although the pattern …

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Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott Jun 1993

Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott

Arkansas Water Resources Center Technical Reports

A study was conducted to compile a GIS database for the Beaver Reservoir Watershed and then use the database to run the Universal Soil Loss Equation and the Phosphorus Index Model on the War Eagle Creek Watershed, a portion of the Beaver Reservoir Watershed database. Characterization of the spat i a 1 properties of the primary attributes compiled for the watershed were reported. In addition, water quality samples taken from War Eagle Creek were analyzed for relationships across the watershed. Erosion in the watershed was lower than expected with well vegetated and fertilized pastures contributing to the reduction of annual …

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