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University of Arkansas, Fayetteville

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Articles 631 - 660 of 766

Full-Text Articles in Earth Sciences

Fate Of Nitrogen From The Disposal Of Poultry Litter: A Simulation Approach, B. A. Ibrahim, H D. Scott Jun 1990

Fate Of Nitrogen From The Disposal Of Poultry Litter: A Simulation Approach, B. A. Ibrahim, H D. Scott

Arkansas Water Resources Center Technical Reports

A computer program was written to simulate the transport of nitrogen after an application of poultry litter to a pasture. The program was written in FORTRAN 77 to run on an IBM PC/AT or compatible personal computer or on a Sun SPARCSTATION. Simulation of water, solute and heat transport was by finite difference. Partition of rainfall into infiltration and runoff was by the SCS curve number method. A comparison was made of the computer model output with the results of a field experiment established at the Main Agricultural Experiment Station at Fayetteville. Poultry litter was applied at a rate of …

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Virus Reduction By The Stanford Onsite Wastewater Treatment System, Mark A. Gross Jun 1990

Virus Reduction By The Stanford Onsite Wastewater Treatment System, Mark A. Gross

Arkansas Water Resources Center Technical Reports

A field study to examine the Stanford Onsite Wastewater Treatment System's ability to remove bacteriophage from wastewater was conducted. MS2 Coliphage was Injected Into the low pressure pipe (LPP) distribution system to achieve an Influent concentration of 1.6 x 106 plague forming units per milliliter (PFU/ml). The bacteriophage was Injected Into the system three times during the day, and samples were taken from drainage tiles of the treatment system. Tile drainage was assayed on conform bacteria host cultures for MS2 phage. The treatment system removed two to three logs (99% to 99.9%) of the phage. During the past two years, …

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A Preliminiary Investigation To Determine The Economic Implications Of The "404" Permit For Constructing Agriculturally Related Reservoirs In Arkansas, Richard K. Ford, Charles R. Britton Jun 1990

A Preliminiary Investigation To Determine The Economic Implications Of The "404" Permit For Constructing Agriculturally Related Reservoirs In Arkansas, Richard K. Ford, Charles R. Britton

Arkansas Water Resources Center Technical Reports

A descriptive inquiry of the economic consequences of federal regulations which restrict the construction of agriculturally related reservoirs in Arkansas's wetlands is presented in this report. The applicable economic principles are identifyed and applied to the situation without the quantifiable information necessary to evaluate the alternatives. The difficulty of collecting the required quantifiable information necessitates the formulation of a different technique to unravel the dilemma. An alternative method for resolving the wetlands allocation question is presented for a public sector decision maker. This unconventional technique suggests that it may be desirable to estimate and compare the costs associated with the …

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Optimal Reservoir Design Criteria In Conjuctive Use Of Surface Water And Groundwater For Soybean Irrigation In Eastern Arkansas, D. R. Edwards, J. A. Ferguson Jun 1990

Optimal Reservoir Design Criteria In Conjuctive Use Of Surface Water And Groundwater For Soybean Irrigation In Eastern Arkansas, D. R. Edwards, J. A. Ferguson

Arkansas Water Resources Center Technical Reports

A computer simulation model, named Arkansas Offstream Reservoir Analysis (ARORA) was developed to simulate present worth of net income from soybean production systems for conditions varying with respect to ground water availability, offstream reservoir capacity, and many other variables. Additional algorithms were incorporated into the model to enable it to optimize reservoir dimensions given realistic constraints and to identify the reservoir capacity corresponding to maximum present worth of simulated net income. The model was written in FORTRAN programming language and requires significant input data in order to provide significant flexibility with respect to the situations which may be accomodated. The …

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Presentation Of Verified Algal Taxa As Reference Sources - Phase Ii, Richard L. Meyer Jun 1990

Presentation Of Verified Algal Taxa As Reference Sources - Phase Ii, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

The focus of this research project was to continue the development of a photographic system which would record living organisms using various forms of light microscopy with correct color and with arrested movement. These demands dictate the use of an electronic flash source with metering and control system located in a position following the passage of the light through the optical train. The system developed uses off-the-shelf components with a modified flashtube holder which positions the tube in the axis of the light beam between the field and iris diaphragm. The light is measured off-the-film so that light from the …

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Dew Chemistry, G. H. Wagner Jun 1990

Dew Chemistry, G. H. Wagner

Arkansas Water Resources Center Technical Reports

From July, 1989 to July 1990 a total of 98 dews and 9 frosts were collected at the University of Arkansas Agricultural Experiment Station, Fayetteville. The total water flux from dews and frosts per year is less than 2% of that from rains. Acid and nutrient fluxes are also much lower in dew. In the following series of ions the number in parenthesis gives the % of the yearly flux of the ion in dew compared to rain for an average year: H+ (0.08), Ca2+ (23), Mg2+(9), K+(20), Na+(5), NH+(12), Cl-(7), S02/4-(5) and N0-/3 (6). A typical dew has a …

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Arkansas Water Resources Research Center Pamphlet, Kenneth F. Steele Jan 1990

Arkansas Water Resources Research Center Pamphlet, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

Arkansas Water Resources Center (AWRC) works closely with state and federal agencies and academic institutions. Priority research categories are: surface water analysis, ground water pollution, surface and ground water quality/quanity, and water resource management.

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Efficiency In Collecting Fossils, Kenneth M. Ball, Leo Carson Davis Jan 1990

Efficiency In Collecting Fossils, Kenneth M. Ball, Leo Carson Davis

Journal of the Arkansas Academy of Science

Two hundred seventy-two kilograms of sediments and fossils were collected from 1 meter square plots on lake beach and river gravel bars to compare the efficiency of surface collecting with that of intensive laboratory processing. Collecting fossils by visual inspection of the outcrop required an average of 14 minutes 56 seconds per square meter and resulted in 319 vertebrate and 1320 invertebrate fossils. The ratio of time spent collecting and processing sediments to time spent in surface collecting fossils was 4.66:1. The ratio of invertebrates produced by the intensive laboratory process to invertebrates produced by surface collecting was 4.80:1. Vertebrate …

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Soil And Lithostratigraphy Below The Loveland/Sicily Island Silt, Crowley's Ridge, Arkansas, Donna Porter, Sam Bishop Jan 1990

Soil And Lithostratigraphy Below The Loveland/Sicily Island Silt, Crowley's Ridge, Arkansas, Donna Porter, Sam Bishop

Journal of the Arkansas Academy of Science

Two stratigraphic units between the Loveland/Sicily Island Silt and the Pliocene sand and gravel on Crowley's Ridge were analyzed to determine their origin and assess the degree of pedogenic development. The Crowley's Ridge Loess, the upper unit, was up to 2.6 m thick, was not laterally continuous, and contained a well developed paleosol. The lower unit was a several meter thick sandy facies of the Pliocene sand and gravel which contained a weak paleosol. Particle size analysis revealed that the upper unit exhibited texture similar to the overlying loess units, with unimodal silt comprising greater than 95% of the clay-free …

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Characterization Of Radioactivity In Hot Springs National Park, Arkansas, C. E. Epperson, N. R. Rhodes Jan 1990

Characterization Of Radioactivity In Hot Springs National Park, Arkansas, C. E. Epperson, N. R. Rhodes

Journal of the Arkansas Academy of Science

No abstract provided.

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Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice Jun 1989

Determining Pesticide And Nitrate Levels In Spring Water In Northwest Arkansas, T. L. Lavy, B. A. Dehart, John D. Mattice

Arkansas Water Resources Center Technical Reports

Occurrences of pesticides in our nations ground water are on the rise. As states become aware of this problem and begin monitoring programs, incidence of contamination will probably increase. Since the problem of pesticides in groundwater is relatively new, little research has centered on the fate of pesticides after they reach the groundwater environment. In Northwest Arkansas efforts to monitor groundwater for pesticides have been small. Twenty-five springs in Northwest Arkansas were sampled in the fall of 1988, and spring of 1989. Analysis for atrazine, alachlor, metolachlor, diuron, and simazine in spring water was preformed using gas liquid chromatography and …

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Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab Jun 1989

Analysis, Design And Implementation Of A Pilot Relational Database For Groundwater In The State Of Arkansas, Ray Hashemi-Nassab

Arkansas Water Resources Center Technical Reports

There are several agencies within the state of Arkansas dealing with underground water. Each agency has its own database that acts as an isolated depository of data. Practically, the communication among these databases is zero, not because there is no need for it, but because the communication is very difficult if not impossible. Data redundancy, inconsistency, and lack of integrity is overwhelming. In this study we have addressed the problem of lack of unity among the databases belonging to different agencies. Also, as an alternative we have developed a relational database. In this database the data was normalized to 4NF. …

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An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker Jun 1989

An Expert System For Managing An Activated Sludge Wastewater Treatment Plant, Sandra C. Parker, David G. Parker

Arkansas Water Resources Center Technical Reports

A diagnostic expert system for an activated sludge wastewater treatment plant has been designed to link with a relational database management system for obtaining operational parameter values that are used by the program to diagnose operational problems that may occur in the process. The problems that are dealt with by the system are bulking sludge, floating sludge, defloculation, ashing, solids washout, foaming problems, high soluble effluent BOD and problems in the aeration system. The link between the expert system and the database is accomplished via programming that is initiated by the expert system program. The operator of the system is …

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Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice Jun 1989

Minimizing The Potential For Groundwater Contamination From Agricultural Point Sources, Joseph H. Massey, Terry L. Lavy, John D. Mattice

Arkansas Water Resources Center Technical Reports

An activated charcoal filtration unit was designed to remove pesticides from leftover pesticide solutions and rinsates generated under farm-like conditions. The system, fabricated for less than $1400 using readily available components, effectively removed the pesticides atrazine, benomyl, carbaryl, fluometuron, metolachlor, and trifluralin from wastewater generated on the University of Arkansas Agronomy Farm located in Fayetteville, AR. A total of 2253 L of wastewater were treated using the system. Of these 1768 L were generated from washing out the spray tank (rinsates) while 485 L stemmed from leftover pesticide solutions that were mixed, but not applied. Typical initial pesticide concentrations in …

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Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis Jun 1989

Improving Irrigation Scheduling And Water Use Efficiency In Cotton, Derrick M. Oosterhuis

Arkansas Water Resources Center Technical Reports

Cotton (Gossypium hirsutum L) is an important crop in the southern United States. The crop is grown in both irrigated and rainfed situations and is seldom free from periods of water shortages at some stage during the season. In recent years the need for consistency in yields and a stable cash flow has resulted in a rapid expansion in the number of irrigated acres of cotton in the Mississippi Delta. Irrigation research has, however, not kept pace with this expansion. This project represents a start at meeting this urgent need. The influence of weather patterns necessitates that these studies be …

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Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott Jun 1989

Simulation Of The Fate Of Nitrogen From The Disposal Of Poultry Litter, H. D. Scott

Arkansas Water Resources Center Technical Reports

A PC/AT computer model was developed to simulate the transport of water, nitrate and ammonia in the soil profile after an application of poultry litter to pasture. The model was written using FORTRAN 77 compiler and can be used on any IBM type compatible computer with a math coprocessor. Poultry litter has been shown to be a potential source of plant nutrients, but mismanagement can result in nitrate pollution of the surface and groundwater. The model is composed of a main program, 11 subroutines and three subprograms. An example was shown of the flexibility and dynamic nature of the computer …

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Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer Jun 1989

Presentation Of Verified Algal Taxa As Reference Sources, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

A data base of the algae of Arkansas ecoregions has been established to describe the numerous taxa that occur within the aquatic ecosystems included in these regions. The organisms were identified with the aid of diverse literature from throughout the world. These sources are written in multiple languages and the living organisms had to be compared with outline or silhouette drawings. These illustrations may include shading, but none present the true color of the organism but only the characteristics of the descriptive source. Primary characteristics used to identify algae is based upon pigmentation of the plastid and the number and …

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Blackland Prairies Of Southwestern Arkansas, Thomas L. Foti Jan 1989

Blackland Prairies Of Southwestern Arkansas, Thomas L. Foti

Journal of the Arkansas Academy of Science

The Blackland Prairie community type has been described in Texas; related communities exist in Alabama and Mississippi. The Arkansas variant of the community has not been described in detail. Since the Arkansas Natural Heritage Commission began a systematic inventory of the community in 1985, more than 36 remnants have been identified that retain substantial natural character. However, all show some degree of disturbance. Based on aerial photo interpretation, aerial inspection, and ground study, an initial description of the community is presented, including original distribution, soil, vegetation and relationship to similar communities of Texas, Mississippi, and Alabama.

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Soil Micromorphologic Features Of Holocene Surface Weathering And A Possible Late Quaternary Buried Soil, Northwest Arkansas, Diane Phillips, Margaret J. Guccione Jan 1989

Soil Micromorphologic Features Of Holocene Surface Weathering And A Possible Late Quaternary Buried Soil, Northwest Arkansas, Diane Phillips, Margaret J. Guccione

Journal of the Arkansas Academy of Science

Micromorphologic features of an alfisol developed in White River alluvium near Fayetteville, Arkansas are typical for this soil order. The A horizon has a relatively high organic matter content and an abundance of quartz sand grains with a silt and clay matrix. Voids are relatively common and some have been partly infilled. In contrast to the A horizon, the E horizon has less organic matter, larger voids, and some weak orientation of the clay matrix. The parent material for these horizons was deposited in the past 4,700 years and these pedologic horizons have formed since that time. In the underlying …

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Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta Aug 1988

Virtually Interactive Large-Scale Model For Arkansas: User's Guide (Vilma), Rosalinda R. A. Cantiller, Richard C. Peralta

Arkansas Water Resources Center Technical Reports

This user’s guide supports the use of VILMA (Virtually Interactive Large-scale Model for Arkansas). This document presents the basic concepts in Chapter I. Chapter II discusses the execution steps that the user follows during a VILMA session. Chapter III provides a detailed illustration of example data files. Chapter IV presents two example VILMA sessions. Finally, Chapter V elaborates on additional concepts. The Appendices consist of relevant program listings, instructions, and example files. In this user’s guide, the word "interactive" means the user enters his responses to the prompts that appear on a computer terminal while he is logged on to …

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Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale Jun 1988

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale

Arkansas Water Resources Center Technical Reports

In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …

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Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis Jun 1988

Development Of A Combined Quantity And Quality Model For Optimal Management Of Unsteady Groundwater Flow Fields, R. C. Peralta, J. Solaimanian, C. L. Griffis

Arkansas Water Resources Center Technical Reports

Presented are alternative techniques for including conservative solute transport within computer models for optimizing groundwater extraction rates. Unsteady two-dimensional flow and dispersed conservative solute transport are assumed. Comparisons are made of the practicality of including modified forms of implicit and explicit finite difference solute transport equations within optimization models. These equations can be calibrated and subsequently used within a MODCON procedure. The MODCON modelling procedure consists of an integrated series of five optimization or simulation modules. The procedure is applicable for either an entire aquifer system or for a subsystem of a larger system. The first module, A, computes physically …

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Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer Jun 1988

Qualitative And Quantitative Aquatic Algal Data Compilation To Determine Macrotrends - Iv, Richard L. Meyer

Arkansas Water Resources Center Technical Reports

A data base of the algae of Arkansas ecoregions has been estabblished by the use of a relational data base management system (dBase III plus). The system was chosen to be readily available for a variety of microcomputers using MS- and PC-DOS. The data base contains taxonomic fields from division through variety, synonymy, authors, initial description, date, and definitive descriptive source. The data are cross-referenced by ecoregion, Round's community and subcommunity designations. The data base contains greater than 1,500 taxonomic records in all divisions and classes of freshwater algae. The data are sortable by any of the included parameters. The …

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Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr Jun 1988

Long-Term Reconstruction And Analysis Of White River Streamflow, M. K. Cleaveland, D. W. Stahle, J. G. Hehr

Arkansas Water Resources Center Technical Reports

A 281-year reconstruction of White River annual runoff at Clarendon, Arkansas, was developed from a regional average of nine Oklahoma, Missouri, and Arkansas tree-ring chronologies (six post oak, Quercus stellata, and three baldcypress, Taxodium distichum). Inhomogeneity of the gaged series was detected with both double mass analysis (using state average total annual Arkansas precipitation) and regression (using the regional tree-ring average). Simple regression calibrated the homogeneous runoff data with the average ring width data from 1930 to 1980. Comparing the reconstruction with independent data verified the regression model. Variance of the reconstruction increases significantly during the 20th century, a change …

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Assessment Of The Effects Of Household Chemicals Upon Individual Septic Tank Performances, Mark A. Gross Jun 1987

Assessment Of The Effects Of Household Chemicals Upon Individual Septic Tank Performances, Mark A. Gross

Arkansas Water Resources Center Technical Reports

A laboratory study and a field study were performed to determine the amounts of specific household chemicals required to destroy bacteria populations in individual domestic septic tanks. The particular chemicals evaluated include liquid chlorine bleach, High Test Hypochlorite (HTH), Lysol disinfectant and Drano crystal. The laboratory study was performed to determine the approximate chemical concentrations to destroy the bacteria in the septic tank, and the field study showed the actual effect of the chemicals upon the bacteria in terms of reduction of the number of bacteria in the septic tank as well as the time required for the bacterial population …

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Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale Jun 1987

Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale

Arkansas Water Resources Center Technical Reports

In 1985, more than 750 million broiler chickens were produced in Arkansas. During the same year over 15 million laying chickens produced 3.6 million eggs. The waste products of these agricultural production systems, poultry litter and manure, were about 1 million metric tons. As a result of land application of these wastes, about 5,000 metric tons of annnonium N and 12,000 metric tons of mineralized nitrogen were applied to Arkansas pastures in 1985. Manures contributed about 2-3 percent of the total. The objective of this research was to quantify major components of the nitrogen cycle which influence the ground and …

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Botanical Evidence For Holocene Movement Of Rock Streams In Arkansas, S. Marie Lookingbill, Malcolm K. Cleaveland, Margaret J. Guccione Jan 1987

Botanical Evidence For Holocene Movement Of Rock Streams In Arkansas, S. Marie Lookingbill, Malcolm K. Cleaveland, Margaret J. Guccione

Journal of the Arkansas Academy of Science

Botanical studies of rock streams on the western half of Rich Mountain and on the north slope of Mt. Magazine in Arkansas question the common presumption that such streams require periglacial conditions to form, and are now inactive relict features in this area. Trees along the margins of the streams examined show abundant evidence of trauma resulting from Late Holocene movement, in the form of bent and tilted stems. Cross sections of trees demonstrate marked eccentric growth associated with tilting and cambial trauma associated with corrasion by rocks. That this damage is not the result of excessive snow loading is …

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Physiography And Hydrology Of The Upper Saline River, Saline And Garland Counties, Arkansas, John D. Rickett Jan 1987

Physiography And Hydrology Of The Upper Saline River, Saline And Garland Counties, Arkansas, John D. Rickett

Journal of the Arkansas Academy of Science

The Saline River is one of two significant river systems in Arkansas that does not have a major impoundment. In the interest of continuing this status, this project was conducted. Thirty-five sites on the four major and six minor tributaries of the upper saline River, Saline and Garland Counties, Arkansas, were visited a total of 58 times between 24 January 1985 and 21 November 1986. Habitat quality was assessed by measuring twelve physicochemical features and flow parameters, analyzing substrate composition and describing stream morphometry. Physicochemical measurements were within the limits of good quality habitat, and most of the readings were …

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Textural And Lithologic Differences Of Cretaceous, Tertiary, And Quaternary Gravels Of South Arkansas, Lesli Wood Jan 1987

Textural And Lithologic Differences Of Cretaceous, Tertiary, And Quaternary Gravels Of South Arkansas, Lesli Wood

Journal of the Arkansas Academy of Science

Stream gravels have been derived from the Ouachita Mountains since at least Cretaceous times. Past studies have assigned ages to gravel deposits in the basins of the Saline and Little Missouri Rivers on the basis of altitude above local floodplains. This study examines the lithologies and textures of seven gravel outcrops ranging in age from Cretaceous to Quaternary to determine whether any patterns of variation based on assigned ages, variable sources, or precise depositional setting can be discerned. No variation patterns could be found for size distributions of sand-sized and larger fractions. However, the amount of silt-clay matrix decreases through …

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Long-Term Effects Of Tillage On The Retention And Transport Of Soil Water, H. D. Scott, L. S. Wood, W. M. Miley Jun 1986

Long-Term Effects Of Tillage On The Retention And Transport Of Soil Water, H. D. Scott, L. S. Wood, W. M. Miley

Arkansas Water Resources Center Technical Reports

Quantitative measurements were made of the physical and chemical properties of two virgin prairie soils, Crowley and Jay, that remain in their native Arkansas environments and of similar soils that had been tilled extensively. Comparisons were made of soil properties at several depths. When compared with the tilled soils the virgin soils had higher organic matter contents, saturated hydraulic conductivities and water retained at several applied pressures. Bulk densities and hydraulic resistances were lower in the virgin soils. For the Crowley silt loam, values of pH and elemental contents of the virgin soil were higher than those of the tilled …

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