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Articles 17641 - 17670 of 17781
Full-Text Articles in Entire DC Network
Potassium Deficiency In Medium Rainfall Areas, William John Toms
Potassium Deficiency In Medium Rainfall Areas, William John Toms
Journal of the Department of Agriculture, Western Australia, Series 4
IT is well known that potassic fertilisers must be used for the successful growth of subterranean clover (Trifolium subterraneum L.) on many soils in the higher rainfall districts of Western Australia.
Recent investigations have shown that some soils in medium rainfall districts are also too low in potassium to grow healthy subterranean clover pastures.
Healthy Pastures, F E. Ryan
Healthy Pastures, F E. Ryan
Journal of the Department of Agriculture, Western Australia, Series 4
IN sweeping away forests to make room for pastures we have taken on the responsibility of maintaining these areas in a condition suitable for the growth of pasture plants.
This is done by a choice of suitable species, fertilising, cultivating, drainage, control of grazing and by weed and insect control.
Minor Elements Can Be Overdone, L T. Jones
Minor Elements Can Be Overdone, L T. Jones
Journal of the Department of Agriculture, Western Australia, Series 4
T H E term "minor elements" which is now commonly used and well understood by farmers and gardeners, refers to the five essential plant foods—copper, zinc, manganese, molybdenum and boron.
These five essential plant foods are needed by all plants in minute quantities and it is relatively easy to use them in excess of actual requirements or even in toxic amounts.
In practice this is not usually a problem with cereals and pastures. The important exception is when zinc alone is added to a cereal crop low in copper and the extra zinc accentuates the copper deficiency, and poorer yields …
Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins
Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins
Department of Agronomy and Horticulture: Faculty Publications
SUMMARY
Good stable soil structure is valuable for promoting the growth of plants and micro-organisms by permitting enhanced aeration and water penetration and by decreasing erosion under some conditions.
Micro-organisms influence water percolation through the soil. They may plug up soil pores with byproducts of growth and reduce water percolation. On the other hand, if a soil containing a large amount of microbial products is stirred and allowed to dry, then the percolation may be high.
Micro-organisms are involved in stabilizing soil structure by their products of decomposition and their cellular binding material, such as mycelia. Microorganisms differ greatly in …
Special Report (1960), Walter A. Lawrance
Special Report (1960), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Addition Of Sodium Nitrate (1960), Walter A. Lawrance
Addition Of Sodium Nitrate (1960), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation
Comprehensive Survey Of Sedimentation In Lake Mead, 1948-49, W. O. Smith, C. P. Vetter, G. B. Cummings, U.S. Bureau Of Reclamation
Publications (WR)
Reservoirs are becoming an increasingly prominent feature of the American landscape. Built for flood mitigation and to change a fluctuating river into a dependable source of water for irrigation, power, and other purposes, they are predestined, like natural lakes, to be destroyed sometime following their creation. Sedimentation sooner or later robs most lakes and reservoirs of their capacity to store water. The significance of sedimentation in the life of Lake Mead, the largest artificial reservoir in the world, was realized when the plan for the reservoir was conceived, and an aerial survey of the floor was made in 1935 before …
Addition Of Sodium Nitrate (1959), Walter A. Lawrance
Addition Of Sodium Nitrate (1959), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Odor Report (1959), Walter A. Lawrance
A Manometric Method For The Determination Of Soil Carbonates In The Field, N. A. Polyzopoulos
A Manometric Method For The Determination Of Soil Carbonates In The Field, N. A. Polyzopoulos
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In soil survey work the method now generally used to evaluate the carbonate content of the soil in the field is to observe the amount of effervescence that takes place when the soil reacts with dilute acid. The four degrees of effervescence usually recognized are designated by the symbols eo, e, es, ev and correspond roughly to a lime content of 0-0.5, 0.5-3, 3-15, and above 15 per cent, respectively. This, or course, is a very rough estimate and therefore a method is needed for the quantitative determination of carbonates in the field with a fair degree of accuracy. If …
Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight
Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen is the most widely needed and the most widely used of the fertilizer elements. Yet, in spite of the voluminous research work of evaluating the nitrogen status of soils, laboratory tests for the purpose of predicting need of nitrogen fertilizer are not very widely used. In general, laboratory tests for nitrogen supplying power have not given satisfactory results. Methods currently employed by a few laboratories can be classified either as biological or chemical. In the former method, the soil is incubated under optimum conditions and the amount of nitrate released over a given period of time is measured and …
A Review Of Fossilization Processes In Different Sedimentary Environments (With Special Reference To The Time Factor Of Deposition Of Ore Minerals Associated With Fossil Material, In Particular The Coprolitic Phosphate Deposits), Giovanna Reggiori Ligasacchi
A Review Of Fossilization Processes In Different Sedimentary Environments (With Special Reference To The Time Factor Of Deposition Of Ore Minerals Associated With Fossil Material, In Particular The Coprolitic Phosphate Deposits), Giovanna Reggiori Ligasacchi
Masters Theses
"This thesis offers a cross/section through some principal fossilization processes involving organic matter (animals and plants) during and after sedimentation. The influence of different environments during fossilization is considered. The chemical composition of some classes of living invertebrates and plants is compared with the chemical composition of same organisms as found in consolidated sediments as fossils.
Some literature on carbonates, oxides, silicates, phosphates, and sulphides in fossils is reviewed with particular attention to those instances where the fossils are associated with ore minerals. Special consideration is given to the occurrence and composition of fecal matter in recent and consolidated sediments. …
An Iron Fulgurite From Nebraska, C. M. Riley
An Iron Fulgurite From Nebraska, C. M. Riley
Bulletin of the University of Nebraska State Museum (1924–2023)
From the time of the ancients man has been impressed with the force of lightning and its effect on the rocks at the surface of the earth. It was Saussure in 1786 who first wrote a scientific account of a true fulgurite, and a wealth of literature has been written about the subject since this time. Many unusual fulgurites have been described, some of which may not truly be the result of lightning. The iron fulgurite is a strange conical object about 3 inches high composed mainly of tiny spheres and filaments of metallic iron intermixed with a small amount …
Addition Of Sodium Nitrate (1958), Walter A. Lawrance
Addition Of Sodium Nitrate (1958), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
An Application Of A Thermodynamic Flow Equation To Water Movement In Unsaturated Soil, Brennan Derry Soane
An Application Of A Thermodynamic Flow Equation To Water Movement In Unsaturated Soil, Brennan Derry Soane
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The movement of water in soil presents many interesting problems to the research worker. It is also a subject which finds wide and important application in agriculture and several branches of engineering.
The object of this work was to examine the usefulness of a new equation of flow of water in unsaturated soil. If valid, this new approach may be able to eliminate some of the gaps in our present knowledge of the subject.
All soil lying above the capillary fringe of a water table is in the unsaturated state with respect to water. This means that in any macroscopic …
Industrial Wastes: Bio-Assays For Control Of Industrial Effluents, Croswell Henderson, Clarence M. Tarzwell
Industrial Wastes: Bio-Assays For Control Of Industrial Effluents, Croswell Henderson, Clarence M. Tarzwell
United States Environmental Protection Agency: Publications
Waste effluents from many industries are toxic to fish and other aquatic life. The control or treatment of these wastes for safe release into receiving waters presents a problem of consider able magnitude.
Much effort has been expended by some industries to solve this problem, primarily through chemical analysis for possible toxic components and then generally by a search of the literature to find out how toxic a particular component may be. Unfortunately, this approach has not been successful, nor can it be expected to be productive of satisfactory answers.
Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner
Medial Pleistocene Fossil Vertebrate Localities In Nebraska, C. Bertrand Schultz, Lloyd G. Tanner
Bulletin of the University of Nebraska State Museum (1924–2023)
The accurate geologic dating of Pleistocene vertebrate localities which occur outside the glaciated regions has always been difficult. Several new fossil localities in Nebraska now provide data for a better understanding of the paleoecology and faunal evidence of the medial Pleistocene of the Great Plains region.
A fossil quarry, containing the remains of both vertebrates and invertebrates, has been discovered in south-central Nebraska (11/2 miles south and west of Angus in Nuckolls County). The fossils are preserved in Sappa silts in a lime concentration zone (C horizon) of a Yarmouth paleosol. The calcium carbonate appears to have been responsible for …
Addition Of Sodium Nitrate (1956), Walter A. Lawrance
Addition Of Sodium Nitrate (1956), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell
Stream Pollution- Aquatic Macro-Invertebrate Communities As Indicators Of Organic Pollution In Lytle Creek, Arden R. Gaufin, Clarence M. Tarzwell
United States Environmental Protection Agency: Publications
Year-round field studies of the com position and ecology of stream communities associated with the purification of organic wastes in streams were initiated on Lytle Creek in October, 1949. This creek, which is located about 45 miles northeast of Cincinnati, Ohio, is a tributary of the Little Miami River. Its drainage basin comprises 27 sq. mi., a third of which is contained within the city limits of Wilmington, Ohio, a city of some 7,412 persons
Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz
Arretotherium Fricki, A New Miocene Anthracothere From Nebraska, J. R. Macdonald, C. Bertrand Schultz
Bulletin of the University of Nebraska State Museum (1924–2023)
A new species of middle Miocene (early Hemingfordian) anthraco-there, Arretotherium fricki Macdonald and Schultz is described based on a cranium from the upper Marsland deposits of Nebraska. The holotype suggests that this genus was derived from the Oligocene genus Elomeryx Marsh.
Addition Of Sodium Nitrate (1955), Walter A. Lawrance
Addition Of Sodium Nitrate (1955), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout
Classification Of Oligocene Sediments In Nebraska: A Guide For The Stratigraphic Collecting Of Fossil Mammals, C. Bertrand Schultz, Thompson M. Stout
Bulletin of the University of Nebraska State Museum (1924–2023)
The Chadron and Brule formations constitute the White River Group in Nebraska and adjacent states. The Brule is divided into the Orella and Whitney members. The latter members are referred to the Medial and Late Oligocene (equivalents of the European Stampian and Aquitanian), while-the Chadron is equated with the Early Oligocene (Sannoisian). Each unit in Nebraska is subdivided into three parts (Lower, Middle, and Upper; or A, B, and C for the Chadron and Whitney, and A-B, C, and D for the Orella). Key beds such as fossil soils (paleosols), Purplish White beds, and volcanic ash layers, when considered with …
Geology At The Secondary School Level, William C. Scott
Geology At The Secondary School Level, William C. Scott
Journal of the Minnesota Academy of Science
No abstract provided.
The Effect Of Land Reduction On Sea Level And Continental Area, Fred Boos Jr.
The Effect Of Land Reduction On Sea Level And Continental Area, Fred Boos Jr.
Journal of the Minnesota Academy of Science
No abstract provided.
Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey
Paleosols Of The Oligocene Of Nebraska, C. Bertrand Schultz, Lloyd G. Tanner, Cyril Harvey
Bulletin of the University of Nebraska State Museum (1924–2023)
Prominent paleosol ("buried" or "fossil" soil) complexes occur at the top of the middle Orella, upper Orella, lower Whitney, and upper Whitney in the Brule formation of Nebraska; and at the top of the "Lower Oreodon," "Middle Oreodon," "Upper Oreodon," and "Leptauchenia" beds in the Brule deposits of South Dakota. These paleosols have regional distribution and appear to be of value in stratigraphic correlations. Major faunal breaks seem to coincide with important buried soil zones, thus indicating that certain paleosols actually represent unconformities. Some of the soils were developed on old land surfaces where deposition was practically at a standstill …
Industrial Wastes, Charles E. Renn
Industrial Wastes, Charles E. Renn
United States Environmental Protection Agency: Publications
This paper presents a summary of experiences with a variety of cyanogenic wastes. The work has attempted to evaluate the interaction of waste bearing waters and the environment in terms of waste disposal design requirements. In this, the approach is somewhat more critical than that commonly taken by fisheries biologists, conservationists, and others who have been concerned with the "preventive" aspects of waste disposal.
The first phases of the work were designed to discover the tolerable limits of certain waste components to fresh water fish. This was undertaken in 1950; in the interval the composition of the wastes has been …
Morphology And Systematic Position Of Some Anomalinid Foraminifera, Billy G. Deaver
Morphology And Systematic Position Of Some Anomalinid Foraminifera, Billy G. Deaver
Masters Theses
"Morphological studies of the following species are the basis for a partial revision of the Family Anomalinadae: Anomalina acuta Plummer, A. midwayensis (Plummer), A. pseudopapillosa Carsey, A. vulgaris (Plummer), Anomalinoides pinguis (Jennings), Cibicides alleni (Plummer), C. beaumontianus (d’Orbigny), c. harperi (Sandidge), Cibicidina danvillensis (Howe and Wallace), Planulina correcta (Carsey), and P. dumblei (Applin); a description of Stensioina americana Cushman and Dorsey, discorbid foraminifer, is included for comparison. The classificatory position and incomplete content of the family are: Superfamily Discorbidea; Family Anomalinidae; Subfamily Anomalininae (revised) -- with ventral supplementary apertures: Anomalina , Planulina ; Subfamily Cibicidinae -- with dorsal supplementary apertures: …
The Effect Of The Bicarbonate Ion On The Respiration Of Excised Roots, Gene W. Miller
The Effect Of The Bicarbonate Ion On The Respiration Of Excised Roots, Gene W. Miller
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
For many years man has been searching for a cure for lime-induced chlorosis. This disease is prevalent throughout the entire western United States and is characterized by a yellowing of the leaves, destruction of the chlorophyll, and eventual death of the plant. It has brought devastation of fruit orchards in Utah, costing fruit producers millions of dollars. Hardly any county in Utah is free from this destructive nutritional disease.
Addition Of Sodium Nitrate (1953), Walter A. Lawrance
Addition Of Sodium Nitrate (1953), Walter A. Lawrance
Walter Lawrance Papers
No abstract provided.
Stream Pollution, Ruth Patrick
Stream Pollution, Ruth Patrick
United States Environmental Protection Agency: Publications
This paper discusses the various ways in which aquatic organisms may be of use in solving problems associated with waste disposal. Since many state and federal laws set forth that nothing may be discharged that is deleterious to aquatic life, the most expedient way to determine the effect of an effluent is to study the aquatic organisms themselves.
In every river that has not been adversely affected by pollution there is a great variety of aquatic life. These organisms do not represent a great mass of living things, but rather they are organized into an intricately balance systems, often referred …