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Soil Science

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Procedure And Structure For An Instructional Laboratory Which Supplements Research, R. S. Adams Jr. Jan 1968

Procedure And Structure For An Instructional Laboratory Which Supplements Research, R. S. Adams Jr.

Journal of the Minnesota Academy of Science

This paper describes the organization of a laboratory course in Soil Chemical Analysis. Students select and pursue small research problems to gain experience in the soil analyses that are discussed in lecture and required in the laboratory. Involvement of the class in an actual research problem proved challenging to both the instructor and the class. The data obtained often supplemented current departmental research. Individual projects were found to be easier to supervise than team problems. This paper reports results of a team project examining parameters of a pot experiment. Shape of the pot, methods of watering, methods of fertilizing, and …


Multiple Cropping Will Increase The Erosion Hazard, W J. Burdass Jan 1968

Multiple Cropping Will Increase The Erosion Hazard, W J. Burdass

Journal of the Department of Agriculture, Western Australia, Series 4

WITH the low price of wool and the price of wheat high in comparison, farmers need little encouragement to increase their acreage of crops.

Unfortunately with increased cropping comes the risk of increased erosion—unless there is a simultaneous increase in the use of conservation practices.


Movement Of Atrazine In Soil Under Furrow Irrigation, Jyothi Veerabhadrappa May 1967

Movement Of Atrazine In Soil Under Furrow Irrigation, Jyothi Veerabhadrappa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Movement of atrazine in response to furrow irrigations was studied using the samples of Timpanogos silt loam soil. Distribution in soil profile of surface applied herbicide was determined by drawing samples of water extracts through porous cylinders. Atrazine quantity was determined by spectrophotometer.

It was observed that the herbicide found in the water extracts was an indication of the quantity present in the soil. The herbicide moved readily with the applied water. Irreversible thermodynamic model could not be applied because of the initial and final boundary conditions. The pattern of movement was in conformity with the chromatographic theory.


The Influence Of Thermo-Gradients Upon Water Movement And Retention In Unsaturated Soils, Jose V. Salazar May 1967

The Influence Of Thermo-Gradients Upon Water Movement And Retention In Unsaturated Soils, Jose V. Salazar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperature differences of about 5, 10, and 15 V, were applied to uniformly packed and insulated horizontal column of Millville silt loam soil using mean temperatures near 13, 14, 15, 16, 17, 18, 19, 20 and 23.5 C. The temperature distribution along the soil column was determined using copper constantan thermocouples. Soil samples were taken to determine volumetric moisture content, and soil water potential, using the vapor pressure psychometer technique. The thermodynamic flow equation of Taylor and Cary, (1964) was used to calculate the hydro-thermal transfer coefficient (ß) as given by:

-ß = d(μw)T / dlnT

where …


The Interaction Between Water Movement, Solute Uptake, And Respirational Energy In Plant Roots, Mohamed Sadek Tawakol May 1967

The Interaction Between Water Movement, Solute Uptake, And Respirational Energy In Plant Roots, Mohamed Sadek Tawakol

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sunflower plants (Helianthus annus, var. Russian mammoth) were grown in Hogland nutrient solution. The roots (after being subjected to treatments with either respiratory inhibitors or respiratory stimulators) were used to measure the flux of water Jw, flux of solute Js , and the rate of respiration Jo.

The thermodynamic theory of irreversible processes was used to examine the interaction between fluxes, and the changes in conductivity under different treatments. The rate equations for a root membrane of unit thickness were developed as:

Jw = LwwVw∆p + LwsRT ln …


Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Vi, Thomas Barrett Apr 1967

Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Vi, Thomas Barrett

Green Revolution

Reprint of section of book Earthworms by Thomas Barrett.


Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part V, Thomas Barrett Mar 1967

Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part V, Thomas Barrett

Green Revolution

Reprint of section of book Earthworms by Thomas Barrett.


Earthworms: In Biological Soil Building - Their Intensive Propagation And Use - Part Iv, Thomas Barrett Feb 1967

Earthworms: In Biological Soil Building - Their Intensive Propagation And Use - Part Iv, Thomas Barrett

Green Revolution

Reprint of section of book Earthworms by Thomas Barrett.


Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Iii, Thomas Barrett Jan 1967

Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Iii, Thomas Barrett

Green Revolution

Reprint of section of book Earthworms by Thomas Barrett.


A Geographical Interpretation Of Coles County Soils Through A Comparative Analysis Of Modern Soil Classification Systems, John C. Klink Jan 1967

A Geographical Interpretation Of Coles County Soils Through A Comparative Analysis Of Modern Soil Classification Systems, John C. Klink

Masters Theses

No abstract provided.


Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Ii, Thomas Barrett Dec 1966

Earthworms: Their Intensive Propagation And Use In Biological Soil Building - Part Ii, Thomas Barrett

Green Revolution

Reprint of section of book Earthworms by Thomas Barrett.


The Influence Of Organic Matter And Ph On Transformations Of Nitrites To Elemental Nitrogen, Mohammad A. Rashid May 1966

The Influence Of Organic Matter And Ph On Transformations Of Nitrites To Elemental Nitrogen, Mohammad A. Rashid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen occupies an important and prominent place in plant and animal nutrition. Large quantities are required by plants and must be available in the soil. Recently the use of nitrogenous fertilizers has increased manyfold. In view of the importance of this element in crop production, even greater use is anticipated in the coming years. In order to make full use of the applied nitrogen, continued investigations of soil-nitrogen relationship are imperative; however, this element presents many complex and challenging problems to investigators.


Movement Of Phosphorus In Soils As Influenced By Chelates And Soil Types, Abd-Elmonem Sayed-Ahmad Mostafa May 1966

Movement Of Phosphorus In Soils As Influenced By Chelates And Soil Types, Abd-Elmonem Sayed-Ahmad Mostafa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The problems of phosphate fertilization have attracted the attention of agronomists, nutritionists, and other biological scientists due to the importance of phosphorus in animal and plant nutrition. However, the fundamental behavior of phosphorus in soil systems is not well understood. Because of its far-reaching effects, a solution of a portion of this problem is of importance.


Nature Of Non-Biological Decomposition Of Nitrite In Acid Media, Mukkatira Kariappa Mahendrappa May 1966

Nature Of Non-Biological Decomposition Of Nitrite In Acid Media, Mukkatira Kariappa Mahendrappa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Curiosity is the cause of investigations, and the thirst for knowledge originates from it. Many times at the end of investigations, the number of questions raised are greater than those for which answers are sought. Therefore, all the information gathered through scientific investigations may not be of value for immediate application in practical life. Nevertheless, no research can be considered less important than the other because the integration of several scientific findings considered less less important at the time of investigation may reveal something of very high significance. Similarly, the study of various transformation reactions that the added fertilizers undergo …


Simultaneous Movement Of Water And Herbicides In Unsaturated Soils, Ming-Shyong Yang May 1966

Simultaneous Movement Of Water And Herbicides In Unsaturated Soils, Ming-Shyong Yang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since weed killers were developed in the early part of the decade beginning in 1940, herbicides have been increasing in use until they are now widely used to control weeds. The application of herbicides has thus become a regular agricultural and ecological practice.


Simultaneous Flow Of Heat And Water In Plant Tissue, Gaylon Sanford Campbell May 1966

Simultaneous Flow Of Heat And Water In Plant Tissue, Gaylon Sanford Campbell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although biological phenomena may be partially described in a general way without the use of mathematics and physics, the experimental results may be more meaningful if they are analyzed on the basis of physical and mathematical laws. The complexity of biological systems has made the application to them of mathematics and physics rather difficult, and only recently has much progress been made. Although it has yet been possible to describe only a few simple biological systems by actual equations, a great deal of qualitative information may be obtained by applying physics and mathematics. Russell (1960, p. 439) said

In principle …


Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation Jun 1965

Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation

Publications (WR)

The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will provide water quality data of Lake Mead prior to releases from Lake Powell as a basis for evaluating Lake Powell's effect on water quality and limnology of Lake Mead. The performance of a DO analyzer was tested and found unsatisfactory at depths below 150 ft. Parameters tested by standard chemical analyses of water samples in the Denver Laboratory and by …


Effect Of Calcium Availability On Alfalfa Grown In Calcareous High Sodium Soils, Harry Irving Nightingale May 1965

Effect Of Calcium Availability On Alfalfa Grown In Calcareous High Sodium Soils, Harry Irving Nightingale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In soil science we shall always be confronted with reactions in soils that involve Ca. Early recognition of this led to experimentation in this area. Due to the fact that Ca deficiency is most common in acid soils, the majority of the experimentation has in the past been largely confined to acid soils and their soil-Ca-plant relationships. There has been relatively little research done with Ca and its availability problems associated with alkaline or sodic soils.


Puccinellia : Outstanding Saltland Grass, C V. Malcolm, S. T. Smith Jan 1965

Puccinellia : Outstanding Saltland Grass, C V. Malcolm, S. T. Smith

Journal of the Department of Agriculture, Western Australia, Series 4

"Puccinellia" is a tussocky perennial grass with an outstanding ability to survive salty and waterlogged conditions.

Considerable areas of saltland in Western Australia are suited to its growth.

Seed is now available commercially and in this article the conditions to which the grass is suited are described and establishment and management methods are suggested.


The Interaction Of Water And Salt Flow In Unsaturated Soils, Mahmoud Hassan Abd-El Aziz May 1964

The Interaction Of Water And Salt Flow In Unsaturated Soils, Mahmoud Hassan Abd-El Aziz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The movements of salt and water, particularly in fairly dry soils or compacted shales, are important processes in both agronomic studies and hydraulics of deep ground water which is important in the location of oil.


Nitrite Reactions In Soil, John Otto Reuss May 1963

Nitrite Reactions In Soil, John Otto Reuss

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Losses of soil nitrogen that cannot be attributed to leaching or crop removal have been observed in many field experiments. Several mechanisms have been proposed to account for these losses.


A Soil And Vegetation Inventory And Analysis Of Three Nebraska Sandhills Range Sites, Donald F. Burzlaff Mar 1962

A Soil And Vegetation Inventory And Analysis Of Three Nebraska Sandhills Range Sites, Donald F. Burzlaff

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This study was undertaken to inventory the soils and vegetation of certain areas of the Sandhills and to seek edaphic characteristics that may be the limiting factor in the distribution of various plant species. Information of this nature will permit formulation of more accurate management practices because of a refinement in delineation of range sites.


The Gascoyne River Catchment Area, W M. Nunn Jan 1962

The Gascoyne River Catchment Area, W M. Nunn

Journal of the Department of Agriculture, Western Australia, Series 4

A RECENT Department of Agriculture survey of the Gascoyne River catchment area has indicated that deterioration of plant cover in the area contributes to the severity of floods which regularly damage the town of Carnarvon.

It is hoped that the results of the survey will help efforts to regenerate the catchment area, and reduce the risk of flooding.


Geological Implications Of Soil Mechanics, James Harrison Quinn Jan 1962

Geological Implications Of Soil Mechanics, James Harrison Quinn

Journal of the Arkansas Academy of Science

No abstract provided.


The Influence Of Temperature On The Impedance To Water Flow Through Plants, Royal Duane Jensen May 1961

The Influence Of Temperature On The Impedance To Water Flow Through Plants, Royal Duane Jensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This era has been termed the atomic or space age. The greatest concern of most people seems to be centered around survival from the destruction and suffering that might be caused by atomic and nuclear weapons. However, along with this, the world is confronted with perhaps a greater disaster--a potential calamity seldom realized by most people, yet a problem which grows more serious in the world each year--a tragedy which would probably be worse than destruction from nuclear weapons. This encroaching catastrophe is starvation.

Even today the majority of the people in the world do not have enough food. Each …


Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice May 1961

Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen has commonly been a deficient element in the cultivated soils of the world since the beginning of agriculture. The general acceptance of the practice of using manures as a means of increasing plant growth, as shown by the records of ancient civilizations, attest to this fact. Since the time of von Liebig there has been an increasing awareness of the importance of this deficiency in soils. As a result of a better understanding of the problem and the increasing availability of commercial forms of nitrogen, a rapid increase in the use of nitrogen fertilizers has taken place in the …


The Effect Of Temperature And Moisture On Nitrification Of Applied Ammoniacal Fertilizer In A Noncalcareous Soil, Merwin Allen Stevens May 1961

The Effect Of Temperature And Moisture On Nitrification Of Applied Ammoniacal Fertilizer In A Noncalcareous Soil, Merwin Allen Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance of nitrogen in world agriculture has been known for many years. But in the past few decades the enormity of the problem of nitrogen economy has been recognized. Along with the recognition of this problem there has developed a great increase in the use of nitrogen fertilizers. Coupled with the increased use of nitrogen there has come about an increasing awareness of the problem involved in the use of nitrogen fertilizers.


Potassium Deficiency In Medium Rainfall Areas, William John Toms Jan 1961

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 Jan 1961

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.


Microorganisms And Soil Structure, T. M. Mccalla, F. A. Haskins Jan 1961

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 …