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Full-Text Articles in Soil Science

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 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 …


Nitrification In Three Different Soils In Polyethylene Bags In The Field Overwinter, William R. Olmstead May 1966

Nitrification In Three Different Soils In Polyethylene Bags In The Field Overwinter, William R. Olmstead

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrification, the process whereby ammonical-nitrogen (NH4+ - N) is changed into nitrate-nitrogen (NO3--N), is one of the more important biochemical processes associated with agriculture. Nitrate appears to be the form of N that most crops can most readily utilize.


The Effect Of Soil Adsorbents On The Thermodynamic Properties Of Soil Water System, Taghi Manbeian May 1966

The Effect Of Soil Adsorbents On The Thermodynamic Properties Of Soil Water System, Taghi Manbeian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It has been generally recognized that the surface phenomena of the solid particles such as shrinking and swelling, water- holding capacity, water' movement, and cation exchange are important in understanding the physical properties of the soil. Clay is the most prevalent material in the colloidal fraction of many soils. Because of the complex nature of the surface of clays and the small size of the particles, the direct study of surface phenomena is difficult. Thermodynamic functions change in accordance with changes and organization within the system. Thus, an examination of the thermodynamics of surface phenomena provides some understanding of the …


The Influence Of Soil Moisture Regimes And Atmospheric Environments On Transpiration And The Energy Status Of Water In Plants, Sampatrao A. Gavande May 1966

The Influence Of Soil Moisture Regimes And Atmospheric Environments On Transpiration And The Energy Status Of Water In Plants, Sampatrao A. Gavande

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant responses to different soil moisture regimes have been extensively studied. Because of interactions between the soil, plant and climatic factors, few convincing generalizations concerning the influence of soil water on the transpiration of water by plants have been established. Generally single factors or at most the interaction of two have been studied at any one time. Useful theories describing the conditions of water retention in plant tissues and movement of water through plants have been proposed. Equally useful theories have been suggested for describing the retention and transmission of water in soil. The integration of these theories and their …


The Course Or Behavior Of Applied Zinc To Soil Containing Different Levels Of Freshly Applied Organic Matter, Artnel Samuel Henry May 1966

The Course Or Behavior Of Applied Zinc To Soil Containing Different Levels Of Freshly Applied Organic Matter, Artnel Samuel Henry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil organic matter consists of a heterogenous mixture of plant, animal, and microbial material in various stages of decomposition. It possesses characteristics which at present are not very well known. Careful studies have been directed towards the behavior of organic matter as it affects plants directly and man indirectly. Consequently, much tire is devoted to its study from the point of metal inactivation and chelation, the earlier investigations failed to produce results worthy of the efforts expended, so a loss of interest in the continued pursuit of knowledge resulted, about two decades ago when it was learned that many polyvalent …


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.


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.


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.


Temperature Dependence Of Soil-Moisture Potential, Jacob Willem Kijne May 1964

Temperature Dependence Of Soil-Moisture Potential, Jacob Willem Kijne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Teachers have noticed that children draw only those objects which they know by name. Doubtless the adult has a similar tendency, exemplified by the researcher, to limit his observations or to relate them to that which can be expressed in the terminology of an existing or newly developed theory. In this thesis the data obtained from studies of the temperature and pressure dependence of the relative vapor pressure over moist soil samples are analyzed by a thermodynamic approach. Not all of the results can be explained completely by means of this tool. Natural systems, such as a moist soil, are …


Effects Of Temperature On Moisture Conductivity In Unsaturated Soil, Richard O'Bannon Meeuwig May 1964

Effects Of Temperature On Moisture Conductivity In Unsaturated Soil, Richard O'Bannon Meeuwig

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water moves in soil in response to potential gradients. The basic equation for this movement is the generalized v=-K▽Φ in which v is volume of water passing through a unit area in unit time, K is the conductivity coefficient, ▽, is the gradient operator (vector), and ▽Φ is the potential gradient.


Influence Of Fertilizer Treatment On The Response Of Sugar Beet Yield To Moisture, Samad Farzanfar May 1964

Influence Of Fertilizer Treatment On The Response Of Sugar Beet Yield To Moisture, Samad Farzanfar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many factors that influence the growth and quality of sugar beets behave in one way under one set of conditions and in quite another under other conditions. Consequently, these factors should be considered together under a dynamic situation to find their interrelations and their influence on sugar beet yield.

This study is a statistical analysis of the interaction of fertilizer and soil moisture potential with the yield of sugar beets grown in a crop rotation under different regimes of irrigation conducted over a period of seven years.

The data are available for the years 1949 through 1956, from an intensive …


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.


Differentiation Between The Ph Effect And The Bicarbonate Ion Effect In Causing Lime-Induced Chlorosis, Hyrum Del Var Petersen May 1963

Differentiation Between The Ph Effect And The Bicarbonate Ion Effect In Causing Lime-Induced Chlorosis, Hyrum Del Var Petersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lime-induced chlorosis has been recognized for many years as a problem where plants are grown on calcareous soils. There are many factors associated with and influencing this form of iron chlorosis and because of this it has been very difficult to determine the relationship between the factors and chlorosis.


Salt Effect On Water Requirements Of Plants, Abdel-Wahhab M. H. Sallam May 1963

Salt Effect On Water Requirements Of Plants, Abdel-Wahhab M. H. Sallam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Water requirement was defined by Briggs and Shantz in 1911 as the ratio of the weight of water absorbed by a plant during its growth to the weight of dry matter produced. Ballard (1933) and Williams (1935) defined water requirement as the ratio of the amount of water transpired to the amount of dry matter produced. Ballard (1933) and Williams (1935) defined water requirement as the ratio of the amount of water transpired to the amount of dry matter formed during the whole or any part of the life cycle of the plant. Miller (1938) and Kramer (1959) postulated that …


A Field Study Of Miscible Displacement In Saturated Soils, Lloyd Dowley Mcfadden Sadler May 1963

A Field Study Of Miscible Displacement In Saturated Soils, Lloyd Dowley Mcfadden Sadler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extensive research has been carried out in both field and laboratory to explain water and solute movement under both saturated and unsaturated conditions. The importance of such work is obvious, since any attempt at exploring land reclamation by leaching or nutrient movement in plant feeding (to name only two) is subject to interpretations and theories of moisture flow.

Water flow through soil during reclamation by leaching can be termed miscible displacement since soil water and leaching water do not have a distinct fluid-fluid interface and will physically mix. It is probable that miscible displacement investigations can contribute to an understanding …


Pressure Dependence Of Soil Water Matric Potential, Bozorg Bahrani May 1963

Pressure Dependence Of Soil Water Matric Potential, Bozorg Bahrani

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The partial specific Gibbs1 free energy or the chemical potential has been shown to be the most desirable thermodynamic function for describing soil-water systems. The absolute value of the chemical potential of soil water cannot be determined. If pure water at standard temperature and pressure is taken as the reference, the difference between the chemical potential of soil water and that of the reference can be measured and is called "soil water potential," which has the dimension of energy per unit mass.

The barometric pressure at the sea level has been accepted as the standard reference pressure. Thus, any …


The Influence Of Advective Energy On Evapotranspiration, Mahmoud Abdel Aziz May 1962

The Influence Of Advective Energy On Evapotranspiration, Mahmoud Abdel Aziz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Evaporation and transpiration from the soil and plant, respectively, have received increasing attention from those who work with water supply, irrigation, and drainage.


On The Enthalpy And Entropy Of Soil Water, Robert A. Kohl May 1962

On The Enthalpy And Entropy Of Soil Water, Robert A. Kohl

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Just twenty years have passed since the first papers were published on the application of chemical thermodynamics to the soil-water system (11, 14). Since then, soil physicists have used thermodynamics in an attempt to characterize and learn more about this intricate system.


The Effect Of Chelates On Phosphorus Availability And Mobility, Salah Ahmed Tahoun May 1962

The Effect Of Chelates On Phosphorus Availability And Mobility, Salah Ahmed Tahoun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil-phosphorus relations and plant-phosphorus relations have attracted the interest of many investigators since Liebig introduced his famous theory about the importance of the mineral matters to the plant in 1840. It was soon realized that phosphorus nutrition was a problem not easily solved for two reasons. 1. The added phosphorus fertilizers, soon after soil application are converted by some reactions in the soil to complex compounds far less soluble, consequently less available to the plant. Conclusions about this process led to controversial debates until it was discovered that a general statement covering all soils was impossible since the reactions involved …


Relations Between Transpiration, Leaf Temperatures, And Some Environmental Factors, Ronald Kay Tew May 1962

Relations Between Transpiration, Leaf Temperatures, And Some Environmental Factors, Ronald Kay Tew

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Transpiration is the loss of water in vapor form from a plant. This is essentially the same process as evaporation except that it is modified by plant structure. Large quantities of water are removed from the soil, transferred through the conducting tissues of the plant, and dissipated into the air each day. As soon as the water is lost to the atmosphere, it becomes unavailable for human use.


Influence Of Compaction And Freezing On The Structure And Permeability Of Some Selected Horizons From Northern Utah Soils, Samir Ramzy Nagmoush May 1961

Influence Of Compaction And Freezing On The Structure And Permeability Of Some Selected Horizons From Northern Utah Soils, Samir Ramzy Nagmoush

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Frequently, in evaluating plant deficiencies, one considers only those soil factors which are associated with the fertility of the soil-- mainly the levels of phosphorus, potash, nitrogen, and organic matter. A certain level of nutrition is essential for plant growth, but in order for the nutrients to exert their maximum influence on the productivity of the soil, it is equally important that a good soil environment be provided and maintained. A good environment requires that good physical conditions of soil, sir, and water be in balance.


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 …


Effect Of Anions On The Sodium Adsorption Capacity And Electrophoretic Mobility Of Sodium Saturated Utah Bentonite, Theron G. Sommerfeldt May 1961

Effect Of Anions On The Sodium Adsorption Capacity And Electrophoretic Mobility Of Sodium Saturated Utah Bentonite, Theron G. Sommerfeldt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sodium saturated Utah bentonite was equilibrated in several concentrations of various sodium salt solutions. The effect of anions on the amount of sodium adsorbed was determined. The effect of anions on the electrophoretic mobility of the clay was also studied. The results are reported herein.

Anions, are generally considered, in the field of surface chemistry, to have no influence on the amount of cations adsorbed or the electrophoretic mobility of negatively charged colloids (5, 10, 28, 41). There is evidence (2, 7, 24, 26, 27, 33) to indicate that anions sometimes have an appreciable effect. If anions influence the amount …


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.


The Effect Of Moisture And Temperature On Transformation Of Applied Ammonium Sulfate In Several Western Soils, Lloyd Richard Hossner May 1961

The Effect Of Moisture And Temperature On Transformation Of Applied Ammonium Sulfate In Several Western Soils, Lloyd Richard Hossner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The conversion of ammonia nitrogen to nitrite and nitrate forms of nitrogen has aroused much attention in the past and continues to receive much of the energy of the present day researcher.


The Influence Of Soil Compaction Upon The Thermodynamics Of Soil Moisture, James E. Box Jr. May 1961

The Influence Of Soil Compaction Upon The Thermodynamics Of Soil Moisture, James E. Box Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The retention of water in soils is a very interesting subject. Soil-water research presents a great challenge to research workers. The challenge is broad in scope and extends from the field problems of large irrigation projects to the atomic scale of the solid-liquid interface.

If scientists are going to describe scientifically soil-water relations, they must ultimately utilize the instruments of science and the language of mathematics. To the end of the latter the mathematics of thermodynamics has been applied in these studies of water retention in soils.