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Articles 11851 - 11880 of 12002
Full-Text Articles in Physical Sciences and Mathematics
Simulating The Water Requirements And Economic Feasibility Of Corn In The Midwest, Wendi L. Palmer, B. J. Barfield, M. E. Bitzer, C. T. Haan
Simulating The Water Requirements And Economic Feasibility Of Corn In The Midwest, Wendi L. Palmer, B. J. Barfield, M. E. Bitzer, C. T. Haan
KWRRI Research Reports
An evaluation of the economics of supplemental irrigation when using a surface water supply must be site specific in order to account for variations in soil moisture holding capacity, watershed area supplying the runoff, climatic conditions, and proposed irrigation management procedures.
With the use of farm specific simulation models to determine grain yields, availability of irrigation water, and economic expenditures involved in irrigation, an economic evaluation of supplemental irrigation can be performed, In the model presented in this report, the Duncan SIMAIZ model is used to predict grain yields using long-term daily weather information. SIMAIZ also determines irrigation water demand …
Fertilizer Recommendations, William O. Thom
Fertilizer Recommendations, William O. Thom
Soil Science News and Views
Fertilizer recommendations are interpreted from a soil test value. The interpretations are based on field research that compares crop yield to soil test levels and the amount of fertilizer applied. These field studies provide data to compare relative yield of a crop for a measured soil test value and fertilizer recommendations are then calibrated to these soil test values.
Soil Drainage---Effects On Crop Production, Kenneth L. Wells
Soil Drainage---Effects On Crop Production, Kenneth L. Wells
Soil Science News and Views
One of the major physical properties of soil which is important to crop production is drainage through the rooting zone. This characteristic greatly influences aeration in the rooting zone, and the degree of aeration greatly influences several important biochemical reactions of economic importance to crop production.
Conservation Tillage Practices, Monroe Rasnake
Conservation Tillage Practices, Monroe Rasnake
Soil Science News and Views
The loss of topsoil from farmlands has become a serious problem in some parts of Kentucky. During the past 20 years, grain crop acreage has tripled. The production of soybeans, which leaves the soil in a condition more susceptible to erosion, has grown from almost none to 1.7 million acres. Much of this increased acreage has come at the expense of soil conserving crops such as hay and pasture on sloping class II and III land with an erosion hazard. Use of large equipment, larger fields, chemical weed control, etc., has added to the scope of the problem with which …
Use Of Annual Legumes As Winter Cover For No-Till Corn, Robert L. Blevins
Use Of Annual Legumes As Winter Cover For No-Till Corn, Robert L. Blevins
Soil Science News and Views
Legumes in crop rotations hsve traditionally provided nitrogen for nonlegume crops since the early history of agriculture. When in association with the proper strains of Rhyzobium bacteria, legumes are capable of fixing atmospheric nitrogen, which when residues from the legumes decompose, enrich the soil content of nitrogen. Legume cover crops recycle other nutrients, thus reducing leaching losses that often occur in soils during the winter and spring seasons. In addition to these advantages, legume cover crops used with no-tillage corn provide a surface mulch which reduces soil erosion, slows evaporation of soil moisture, increases infiltration of rainfall, and increases soil …
Effects Of Soil Erosion On Productivity, Wilbur Frye
Effects Of Soil Erosion On Productivity, Wilbur Frye
Soil Science News and Views
About 75 percent of Kentucky's agricultural land is sloping enough that potential erosion losses must be considered in its management. In addition to the effect of soil erosion on water pollution is the question of its effect on the productivity of the soil. This is a complex question due to the interactions of the many factors that affect crop growth. Furthermore, the same degree of erosion has a greater adverse effect on some soils than on others. The kind of erosion that has taken place or is taking place is a major factor in making land use decisions for crop …
Delayed Nitrogen Applications On Corn, Grant W. Thomas
Delayed Nitrogen Applications On Corn, Grant W. Thomas
Soil Science News and Views
A method of fertilizer application that was standard practice 30 to 50 years ago has become important once again, and for the same reason. When nitrogen fertilizer was expensive and corn was cheap, it was considered prudent to save back some of the nitrogen fertilizer and apply it when the corn was "knee-high." This was thought to be safer because some of the nitrogen added at planting might be lost before the corn was big enough to take advantage of it. The increasing cost of nitrogen fertilizer has made efficient use of this product important again.
Soybean Inoculation, J. L. Sims
Soybean Inoculation, J. L. Sims
Soil Science News and Views
Well-nodulated soybean plants are needed for most efficient soybean production. Recent research by University of Kentucky Agronomy Department personnel indicated that on Maury soil without N fertilizer, nodulating plant types of Clark 63 variety yielded 8 bushels per acre more than the non-nodulating Clark 63. With application of 125 lbs N per acre to the non-nodulating type only, both types yielded the same, showing the value of good nodulation.
An Avoidance Response Bioassay For Aquatic Pollutants, Jeffrey A. Black, Wesley J. Birge
An Avoidance Response Bioassay For Aquatic Pollutants, Jeffrey A. Black, Wesley J. Birge
KWRRI Research Reports
Avoidance response bioassays were conducted with eight aquatic contaminants, including cadmium, copper, mercury, zinc, chloroform, dioctyl phthalate (DOP), trisodium nitrilotriacetic acid (NTA), and phenol. Tests were performed in a dual-channel fluviarium system, and the toxicant injection procedure used provided good regulation of exposure concentrations. Juvenile stages of largemouth bass (Micropterus salmoides), bluegill sunfish (Lepomis macrochirus), and rainbow trout (Salmo gairdneri), and tadpoles of the American toad (Bufo americanus) proved to be suitable animals for evaluating avoidance or attraction responses. The trout was the most sensitive species tested.
Avoidance was significant in tests …
Determination Of Sediment Filtration Efficiency Of Grass Media, David T. Kao
Determination Of Sediment Filtration Efficiency Of Grass Media, David T. Kao
KWRRI Research Reports
Vegetative filters serve the purpose of retarding flow. As a result the sediment carrying power of flowing water in a vegetated channel is greatly reduced and silting takes place along the section where the vegetation is planted.
The mechanism of the filtering action of real or artificial vegetation can be described by a simplified principle, in that a gross reduction of turbulent fluctuation of the fluid is involved. This in turn allows the sediment particles to settle under the force of gravity more readily. In the case of nonsubrnerged flow, solid particles may settle out even faster due to the …
An Environmental Study Of The Origin, Distribution, And Bioaccumulation Of Selenium In Kentucky And Barkley Lakes, B. E. Mcclellan, Kenneth J. Frazer
An Environmental Study Of The Origin, Distribution, And Bioaccumulation Of Selenium In Kentucky And Barkley Lakes, B. E. Mcclellan, Kenneth J. Frazer
KWRRI Research Reports
Many samples of water, bottom sediment, and fish were analyzed for toxic metal ion content. The samples were collected from several selected sites along Kentucky and Barkley Lakes as well as the Cumberland River and several sub-impoundments along these aquatic systems. Emphasis was placed on selenium, although several other metal ions were determined. The results showed that there are no serious pollution problems with As, Cd, Cr, Cu, Hg, Pb, Se, Sr, Zn, or Zr at any of the sites examined. Actually, none of the trace metals examined even come close to the EPA limits on fish, with the exception …
High-Carbonate And Low-Silica Stone In The High Bridge Group (Middle Ordovician), Fayette County, Central Kentucky, Garland R. Dever Jr.
High-Carbonate And Low-Silica Stone In The High Bridge Group (Middle Ordovician), Fayette County, Central Kentucky, Garland R. Dever Jr.
Information Circular--KGS
The High Bridge Group (Middle Ordovician) of central Kentucky, a major source of limestone and dolomite for construction and agricultural stone, is also a potential source of stone for industrial uses requiring carbonate rocks of high chemical purity. Chemical analyses of foot-by-foot samples from a Fayette County core show that several thick zones of high-carbonate and low-silica stone are present in the High Bridge at a minable depth.
Bibliography Of The Kentucky Geological Survey, 1839 Through 1978, Kentucky Geological Survey
Bibliography Of The Kentucky Geological Survey, 1839 Through 1978, Kentucky Geological Survey
Information Circular--KGS
It is the hope of the authors that all of the various publications and maps of the Kentucky Geological Survey are included in this bibliography. It is our intent to revise, supplement, and update the publication lists in "Geological Research in Kentucky" by Willard Rouse Jillson (1923).
During its history the Kentucky Geological Survey has suffered losses from two disastrous fires, one at Frankfort in 1929, and a second at Lexington in 1948. Many maps and some of the reports were reprinted after 1948 in Series VIII, but so many of the earlier publications were lost that they are now …
Ground Driven Powered Tillage, Larry G. Wells, E. M. Smith, D. E. Hammett, H. J. Thompson Jr.
Ground Driven Powered Tillage, Larry G. Wells, E. M. Smith, D. E. Hammett, H. J. Thompson Jr.
Biosystems and Agricultural Engineering Faculty Publications
A ground driven powered tillage device is described which utilizes a passive rolling coulter propelled through the soil by a prime mover. The reaction torque imparted by the soil to the coulter is delivered via a torque transfer unit to a powered tillage blade. The tillage blade rotates counter to the direction of the passive rolling coulter and prepares a tilled furrow of some predetermined depth for seed placement and coverage.
Analysis is presented in which the torque developed by a passive rolling coulter engaging the soil is predicted. A relationship is presented for determining the velocity ratio between the …
Economic Comparison Of Alternative Burley Tobacco Harvesting Practices By Computer, Thomas C. Bridges, Larry G. Wells, George A. Duncan, John N. Walker
Economic Comparison Of Alternative Burley Tobacco Harvesting Practices By Computer, Thomas C. Bridges, Larry G. Wells, George A. Duncan, John N. Walker
Biosystems and Agricultural Engineering Faculty Publications
The computer model CATCH (Computer Analysis of Tobacco Cutting and Housing) was developed to provide the individual tobacco producer with management information concerning alternative methods of harvesting burley tobacco. CATCH utilizes specific producer in-puts to analyze 24 alternative burley production systems and presents up to four economic rankings containing costs, equipment and labor for each system. The economic rankings aid the producer in decision making with regard to his own operation.
Effects Of Organic Compounds On Amphibian Reproduction, Wesley J. Birge, Jeffrey A. Black, Robert A. Kuehne
Effects Of Organic Compounds On Amphibian Reproduction, Wesley J. Birge, Jeffrey A. Black, Robert A. Kuehne
KWRRI Research Reports
Aquatic toxicity tests were conducted with atrazine, carbon tetrachloride, chloroform, methylene chloride, trisodium nitrilotriacetic acid (NTA), and phenol. Each compound was administered to developmental stages of three to five amphibian species. Exposure was initiated at fertilization and maintained through 4 days posthatching. Test responses included lethality and teratogenesis. Different amphibian species exhibited varying degrees of tolerance to the selected compounds. Greatest tolerance usually was observed for the more broadly adapted semi-aquatic and terrestrial species (e.g., Bufo americanus, Bufo fowleri). The more sensitive amphibians usually included those species which normally are restricted to aquatic or moist habitats (e.g., Rana …
Charged Membrane, Low Pressure Ultrafiltration To Treat Acid Mine Drainage Waters, Dibakar Bhattacharyya, Robert B. Grieves, Shiela Shelton
Charged Membrane, Low Pressure Ultrafiltration To Treat Acid Mine Drainage Waters, Dibakar Bhattacharyya, Robert B. Grieves, Shiela Shelton
KWRRI Research Reports
Low-pressure ultrafiltration with negatively-charged, non-cellulosic membranes is shown to be a feasible process in terms of achieving the simultaneous separation of dissolved metals (and sulfate) and of suspended solids from acid mine drainage water. The process is evaluated in terms of the simultaneous achievement of good water flux without membrane fouling and of adequate ultrafiltrate quality at high water recovery for water reuse operation.
At a transmembrane pressure of 5.6 x 105 N/m2, water fluxes in the range of 5.8 x 10-4 cm/sec to 12.5 x 10-4 cm/sec could be obtained at 97% water recovery. …
A Computer Model For Evaluating Corn Harvesting, Handling, Drying And Storage Systems, Thomas C. Bridges, Otto J. Loewer Jr., John N. Walker, Douglas G. Overhults
A Computer Model For Evaluating Corn Harvesting, Handling, Drying And Storage Systems, Thomas C. Bridges, Otto J. Loewer Jr., John N. Walker, Douglas G. Overhults
Biosystems and Agricultural Engineering Faculty Publications
No abstract provided.
The Influence Of Harvest Rate And Drying Time On Grain Drying And Storage Facility Selection, Thomas C. Bridges, Otto J. Loewer Jr., Douglas G. Overhults
The Influence Of Harvest Rate And Drying Time On Grain Drying And Storage Facility Selection, Thomas C. Bridges, Otto J. Loewer Jr., Douglas G. Overhults
Biosystems and Agricultural Engineering Faculty Publications
No abstract provided.
Emission Of Microbial Aerosols From Polluted Waters In Densely Populated Regions, Lois S. Cronholm
Emission Of Microbial Aerosols From Polluted Waters In Densely Populated Regions, Lois S. Cronholm
KWRRI Research Reports
The air surrounding three activated sludge tanks was sampled over a two year period for the emission of bacterial aerosols under a variety of climatic conditions and at varying distances upwind and downwind of the aerated tanks. All plants emitted species of enteric bacteria which are significant as index organisms and as frank pathogens. The emission pattern of these bacteria were influenced by distance from the plant and wind direction. Within the parameters of a plant, defined arbitrarily in this study by sampling sites less than 150 m upwind and less than 900 m downwind, distance from the source was …
Development Of A New Technique For The Analysis Of Pesticides In Water, Prasad K. Kadaba, Pramode K. Bhagat, Radko Osredkar, V. R. K. Murthy
Development Of A New Technique For The Analysis Of Pesticides In Water, Prasad K. Kadaba, Pramode K. Bhagat, Radko Osredkar, V. R. K. Murthy
KWRRI Research Reports
A Nuclear Double Resonance Spectrograph has been designed and constructed with emphasis on quadrupolar nuclei of half-integral spins. The use of a data acquisition and processing system featuring the A/D converter, signal averager with built in fast Fourier transformation hardware greatly improves the S/N ratio. The spectrograph has been used to detect certain organochlorine, carbamate and symmetrical triazine pesticides. Concentration levels that can be detected range from 15 to 100 micrograms per liter. Since the measurements are done below ice temperatures, heat-labile compounds can be detected without conversion to more suitable derivatives as in gas chromatography. Fats and oils in …
Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer
Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer
KWRRI Research Reports
This project was designed to determine the effects of nitrogen fertilization on the quality and quantity of streamflow eminating from an eastern hardwood forest watershed. A 40.67 ha watershed, located in mountainous eastern Kentucky, was aerially fertilized in late April 1975. The forest stand was principally oak, hickory, and yellow poplar, 50 - 55 years of age and in a relatively undisturbed condition. A helicopter applied anunonium nitrate at a rate of 504 kg/ha. Because a large part of applied nitrogen fertilizer ends up in the highly mobile nitrate nitrogen.form, this is the principal ion monitored in this study. No …
A Proposed Revision Of Kentucky's Water Rights Legislation, Richard Ausness
A Proposed Revision Of Kentucky's Water Rights Legislation, Richard Ausness
KWRRI Research Reports
Kentucky's present system of water law consists of a statutory water withdrawal permit system superimposed upon a body of common-law water rights doctrine. The rights of water users are often uncertain under this system, particularly in periods of water shortage. The proposed revision of Kentucky's existing water rights legislation, would greatly reduce the significance of common-law water rights and would remedy some of the weaknesses in the present statute.
Part 1 of the proposed statute establishes an administrative structure; Part 2 deals with water withdrawal permits; Part 3 retains the present statute's provisions on the regulation of dams and impoundments, …
Effects Of Soil Injection Of Liquid Dairy Manure On The Quality Of Surface Runoff, I. J. Ross, S. Sizemore, J. P. Bowden, C. T. Haan
Effects Of Soil Injection Of Liquid Dairy Manure On The Quality Of Surface Runoff, I. J. Ross, S. Sizemore, J. P. Bowden, C. T. Haan
KWRRI Research Reports
Liquid dairy manure has been injected on the soil contour to depths of 6 and 12 inches and applied to the surface of a Bluegrass sod and a bare tilled soil. Application rates of 9,250 gallons per acre were used. Runoff from 9-foot-square plots which were sprinkled at rates of 2.5 inches per hour on sod and 1.5 inches per hour on bare soil was collected and analyzed for various pollution parameters including COD, N, TS, TSS, pH, DO, and Fecal Coliform. The effects of pollutant yield in the runoff have been determined for various treatments.
Injection of the manure …
Evaluation Of Detention Basins For Controlling Urban Runoff And Sedimentation, C. T. Haan, A. D. Ward
Evaluation Of Detention Basins For Controlling Urban Runoff And Sedimentation, C. T. Haan, A. D. Ward
KWRRI Research Reports
This report summarizes the work completed under the research project "Evaluation of Dentention Basins for Controlling Urban Runoff and Sedimentation." The main project accomplishments were:
(1) a demonstration of the desirability of considering systems of urban stormwater detention basins as opposed to individual basin design,
(2) the development of a systems analysis approach for least cost selection of a system of dentention basins for meeting a preset hydrologic objective,
(3) the development of a mathematical, computer-based simulation model of the performance of sediment retention basins,
(4) partial verification of the sediment basin model and
(5) the development of design recommendations …
Removal Of Chloroform From Drinking Water, John S. Zogorski, George D. Allgeier, Robert Lee Mullins Jr.
Removal Of Chloroform From Drinking Water, John S. Zogorski, George D. Allgeier, Robert Lee Mullins Jr.
KWRRI Research Reports
The overall objective of this investigation was to evaluate via laboratory experiments the technical feasibility of reducing trihalomethane levels in drinking water. Special attention was directed at the removal of chloroform since: (a) it is the only trihalomethane which has been shown to be carcinogenic in animal tests; and (b) this compound generally comprises the largest fraction of the total trihalomethane content of chlorinated waters in Kentucky. Trihalomethanes are present in municipal drinking waters due to the reaction of free chlorine with naturally occurring compounds, collectively called "precursors".
A variety of treatment processes and potential modifications (or additions) to existing …
Organized Resistance To An Imposed Environmental Change: A Resevoir In Eastern Kentucky, William F. Schweri Ii, John Van Willigen
Organized Resistance To An Imposed Environmental Change: A Resevoir In Eastern Kentucky, William F. Schweri Ii, John Van Willigen
KWRRI Research Reports
This is a case study of a group organized to resist the construction of an Army Corps of Engineers reservoir project located in Eastern Kentucky, More specifically the account describes how a group of landowners organized themselves and enacted an increasingly complex strategy of resistance. Within this framework perceived costs, leadership and authority and group organization are considered.
The primary method employed in this research was that of repeated interviews with members of the resistance organization who were identified as key informants. These interviews were carried out on both structured and unstructured bases.
The formal analysis of the voluntary association …
Design Of A Reliable, Inexpensive Recording Rain Gage Which Utilizes Solid-State Memory, Stephen A. Dyer
Design Of A Reliable, Inexpensive Recording Rain Gage Which Utilizes Solid-State Memory, Stephen A. Dyer
KWRRI Research Reports
Researchers working in the general area of water resources frequently have need for precipitation data. Unfortunately, the cost of commercially available recording rain gages is often greater than $1,000 per unit. This report describes a microprocessor-controlled remote recording rain gage which is capable of unattended operation for periods of greater than a month that costs less than $400 in single quantities. The laboratory prototype uses a tipping bucket to collect precipitation in 0.01-inch increments. The time of the bucket tip is stored, using an offset binary format, in solid-state memory. A complete description of the gage hardware is presented along …
Predicted And Measured Drainable Porosities For Field Soils, R. W. Skaggs, Larry G. Wells, S. R. Ghate
Predicted And Measured Drainable Porosities For Field Soils, R. W. Skaggs, Larry G. Wells, S. R. Ghate
Biosystems and Agricultural Engineering Faculty Publications
Experiments were conducted on large field cores to determine the relationship between drainage volume and water table depth for five soils. The measured drainage volumes were less than predicted from the soil water characteristics for three soils, but were in good agreement for the other two. Drainable porosities were calculated from both theoretical and experimental drainage volume-water table depth relationships by assuming that the unsaturated zone is essentially 'drained to equilibrium, with the water table. The experimental drainable porosities thus obtained were less than predicted.
Drainable porosities for drainage in two-dimensions were calculated from experimental results for one-dimension by assuming …
The Response Of Various Soil Strength Indices To Changing Water Content And Bulk Density, Larry G. Wells, O. Treesuwan
The Response Of Various Soil Strength Indices To Changing Water Content And Bulk Density, Larry G. Wells, O. Treesuwan
Biosystems and Agricultural Engineering Faculty Publications
Various soil strength parameters were measured in the laboratory using a bevameter and a recording soil cone penetrometer. Measurements were made at various levels of soil bulk density and water content. Results were discussed in terms of similar published analyses. Two dissimilar methods of predicting vehicular tractive performance were compared and evaluated in terms of potential utility with respect to prediction of soil trafficability.