Soil Science Commons^™

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …

A Measure Of The Amount Of Phosphate Adsorption And The Rate Of Release Of Indigenous Phosphate From A Desert Soil, Robert Lindsey Evans

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The capacity of a calcareous desert soil, Thiokol silt loam, to retain natural, as well as added, orthophosphate-P was measured by equilibrium adsorption employing a batch technique and evaluated using the two-slope Langmuir adsorption isotherm. From these data, corrected to account for indigenous soil P, a hypothesis was formulated as to the nature of retention of P by the soil, including the identification of two interfacial reactions involving P, and a value calculated for the adsorption maximum as defined by the Langmuir isotherm equation for P with soil at each of two soil depths and three constant temperatures within the …

An Intensive Edaphological Characterization Of The Soils Of Malambito Experimental Station And Its Implications In Future Agricultural Research, William L. Rubink

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Malambito Experiment Station, in the Atlántico III project area, Department of Atlántico, Colombia, had almost no quantitative edaphological data on which to base agricultural research. Unexplainably low general yields as well as problem areas of deficient plant growth only confounded the results of field plot experiments. Intensive soil sampling and subsequent measurements of pH, EC_e of the saturation extract, and the four major cations disproved the previous suggestions that the crop growth problems were related to saline, sodic, or degraded soil conditions. The Ca/Mg+K+Na ratio, although significant when correlated with plant height, was sufficient explanation for only a small …

An Examination Of The Inorganic Nitrogen Status Of A Soil Of The Alaskan Coastal Tundra Plain, Norton R. Munn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This experiment was designed to measure in situ concentrations of NH₄⁺ and NO₃^--N in a soil of the arctic coastal tundra plain, to determine if nitrification was taking place in this soil and to determine if the vascular plants growing in this soil could assimilate NH₄⁺-N.

The extractable NH₄⁺-N concentration was approximately 40 μg/g in the 0₁ horizon and 10 μg/g in the 0₂ horizon. The NO₃^--N concentration was approximately 5 μg/g in the 0¹ horizon and 4 μg/g in the 0_{2 …}

Evaluation Of The Filter Paper Method For Estimating Soil Water Potential, Samir Al-Khafaf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The filter paper method for measuring soil water potential was evaluated. The method was calibrated using salt solutions (-1.4 bars to -22.4 bars), sample chamber psychrometer (-1 to -50 bars), pressure plate (-0.1 to -15 bars) and soil column at equilibrium (0 to -0.2 bars). It was found that the absolute temperature had little effect on the predicted soil water potential, but a temperature variation had a large effect. It was found that the temperature fluctuation must be small. The predicted water potential was influenced by the type of contact of the soil with the filter paper. It is suggested …

Model For Predicting Simultaneous Distribution Of Salt And Water In Soils, Satish C. Gupta

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of water and salt movement in soils is necessary for development of a management scheme for controlling the quality of irrigation return flow. A computer model was developed to predict the distribution of water and salts in the root zone under varying initial and boundary conditions. The model consists of water flow and salt flow sub-models. The water flow sub-model considers the numerical approximation of the general water flow equation with modification for water loss by evapotranspiration (and thus root extraction). The salt flow sub-model considers the mass flow of salts, chemical exchange, precipitation or dissolution of CaCO_{3 …}

Potentiometric Titration Of Sulfate Using A Lead-Mercury Amalgam Indicator Electrode, Charles W. Robbins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A lead sensitive indicator electrode was constructed with a 70 percent lead and 30 percent mercury amalgam billet. Sulfate concentrations in pure solutions, natural waters, and soil saturation extracts were determined potentiometrically using the lead-mercury amalgam indicator electrode and a standard calomel reference electrode. Sulfate concentrations over the range 0.4 to 20 milliequivalents sulfate per liter were determined with an automatic titrator and compared to a turbidimetric method for accuracy and precision. The values obtained by the two methods from twelve saturation extracts and three subsurface drainage waters were not significantly different and the potentiometric method was generally more precise. …

Model For Estimating Soil Water Flow, Water Content, Evapotranspiration And Root Extraction, Musa N. Nimah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical model was developed to predict water content profiles, evapotranspiration, water flow from or to the water table, root extraction and root water potential at the surface as functions of time under unsteady state conditions.

The model was tested in the field at The Hullinger Farm near Vernal, Utah, in 1970 and 1971. Comparison of water content-depth profiles show excellent agreement at the end of a 9- day run in 1970 on oats seeded to alfalfa. In 1971 with alfalfa as the crop, the data show best agreement, between predicted and computed water content-depth profiles, 48 hours after any …

Effect Of Early Growth Cultivation On Beans And Sweet Corn, Raymond L. Cartee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations involving four cultivation treatments were conducted at the Utah State University Greenville Experimental Farm to determine the effect of these treatments on yields of beans and sweet corn. The effects of the different treatments on soil water content, soil temperature, and weed control in beans and corn were investigated. The effect of cultivation on the degree of root rot infection and the effect of different planting dates were also investigated in the bean study.

The pre-emergence treatment (ridged just before the plants emerge) produced a 48 percent greater bean yield and a 40 percent greater corn yield than the …

The Effect Of Alternate Wetting And Drying On The Ammonium And Nitrite Nitrogen Transformation In Soils, Virupax C. Baligar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations were carried out to study the effect of alternate wetting and drying cycles on the mineralization, nitrification, and denitrification of soil nitrogen in two soils, in the presence or absence of added ammonium and nitrite. Soils were analyzed at the end of each drying cycle for total inorganic nitrogen, ammonium, and nitrite nitrogen. Gaseous products, i.e., ammonia, and the oxides of nitrogen (NO and NO₂) were collected in the course of drying for determination.

The drying cycles accelerated the rate of nitrogen mineralization in both soils and further increased the oxidation of applied and available ammonium. The …

Role Of Transition Metals In Nitrite Decomposition In Soil, J. S. Bajwa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Iron and copper increased the decomposition of nitrite significantly during the first two hours of reaction when 150 parts per million (ppm) of nitrite and nitrogen was added to an acidic soil. Manganese was found to have a slight effect. There was no additional effect of the added metals after two hours reaction time.

The higher concentration of metals was not effective in catalyzing the decomposition of the added nitrite in nitrogen. All the added nitrite nitrogen was not recovered and the deficit could be due to the formation of nitrogen gas.

A Comparative Study Of Boron Adsorption By A Calcareous And An Acid Soil, Namik M. Ali Rashid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The adsorption of boron by Aiken clay loam and Vernal sandy loam was studied in the boron equilibrium concentration range of 0 to 40 ppm. Adsorption data were obtained at 11, 20 and 30°C. The data were analyzed by the application of the Langmuir adsorption isotherm. It was concluded that, in both soils, the adsorption of boron occurred on three distinct sites or regions.

The acid ferrigenous Aiken soil had a higher adsorption capacity for boron than the calcareous Vernal soil when compared on a unit mass basis. On the unit area basis, however, the Vernal soil adsorbed more boron …

Calcium Carbonate Dissolution And Precipitation In Water: Factors Affecting The Carbonate Saturometer Method, Lyle M. Dabb

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The carbonate saturometer method developed by Weyl (1961) was studied in respect to the effect of several variables on the solubility of carbonates. The solubility of three solid carbonate materials was measured in four different salt solutions, at four ionic strengths, and at two different temperatures. The solids studied included: calcite, dolomite, and a calcareous soil.

It was found that the three solid carbonate materials varied in solubility from a low in the soil carbonates to a high in dolomite.

Increasing the ionic strength of the solution increased the solubility of most of the solid carbonate materials.

By decreasing the …

Effect Of Time And Rate Of Application Of Nitrogen On The Yield Of The Mexican Wheat Under The Semi-Arid Conditions Of Tunisia, Habib M. Halila

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of the time and rate of application of nitrogen on the yield of high yielding varieties of wheat was studied under the semiarid conditions of Northern Tunisia.

Analysis of the experimental data showed that nitrogen increased the yield of wheat in most locations which were chosen for this experiment.

In high rainfall areas, late application of nitrogen (tillering, jointing stages) was more effective than early applications. The optimum yield was obtained by applying 90 kilograms of nitrogen per hectare.

In the medium to low rainfall area, early applications (seeding time) were more effective than the late ones. The …

Relationship Of The Soil Water Content And Microclimate To The Plant Growth Water Use Relationship Of Several Plants, Philip Dean Sandberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies involving field plots, lysimeters, and garbage can lysimeters showed that an intermediate soil water level produced the most growth for a given amount of water use by oats, corn, and barley. For crested wheatgrass the lowest water level produced the most growth per water used. Field plots which were covered with sheet metal between the rows produced more plant growth per water used than the uncovered plots for the crops used in this study. One year's data were obtained on the effect of positioning the garbage can lysimeters. One half of the cans were placed on the soil surface …

The Effect Of Early Spring Clipping And The Level Of Nitrogen Fertilizer On The Yield Of Improved Pastures, North Logan, Utah, Dechar Sumrit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The influence of agronomic practices on forage production and chemical composition of grass-legume pasture mixture was studied at the Utah State University Dairy Farm, North Logan, Utah, during spring and summer, 1970. The soil is a well-drained Millville silt loam that has about a 1 percent slope. It is high in potash, phosphorus, and lime, having a pH of 7.9.

Analysis of the clipping management showed that the early spring clipping decreased the yield of forage. The losses in total yield due to spring clipping were approximately four to five times the yields received in early spring clipping. The grasses …

Magnesium Ion Inhibition Of Calcium Carbonate Precipitation And Its Relation To Water Quality, John J. Hassett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of Mg⁺⁺ ion on the solubility of calcium carbonate was determined using P. K. Weyls "carbonate saturometer."

The amount of calcium carbonate precipitated or dissolved was measured for five series of waters when equilibrated with solid carbonate.

It was found that the effect of Mg⁺⁺ ion on solubility depend upon the nature of the solid phase: surface area, coprecipitated Mg⁺⁺, minerology, etc.

Pure low area calcite showed an increase in solubility which could be explained by ion-pair formation, while its other carbonates departed from this behavior.

Areal And Temporal Variations In Developmental Phases Of Syringa Vulgaris L. Throughout The Western United States, Joseph Michael Caprio

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper presents the results of the analysis of 10 years of information 1957-1966 on three phases-- begin, peak and end bloom-- of the purple common lilac (Syringa vulgaris L.) using data recorded at approximately 1,000 locations throughout the Western Region of the United States.

The pattern of geographical advance of the various bloom phases is determined by both a manual mapping procedure developed by the author and by standard statistical methods. Manually drawn isophanes for the various elevations for begin bloom phase are based entirely upon the first 5 years of record, 1957-1961. A Zones of Adjustment map to …

Cation Exchange And Transport In Soil Columns Undergoing Miscible Displacement, Sung-Ho Lai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical model was developed to predict the exchange of one cation by another in a soil column undergoing one dimensional cation solution displacement under steady state flow conditions. The model allowed prediction of both the solution and exchanger phase concentration of the cation in question.

The model consists of a material balance equation which is a parabolic type partial differential equation. The assumption was made that equilibrium was reached instantaneously between the cations in the solution phase and the exchanger phase. This assumption reduced the material balance equation to a form that allowed numerical solution providing the data concerning …

The Effect Of Chemical Competition On Thermodynamics Of Bacterial Adsorption, Deorao R. Khairnar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this investigation was to study the effect of chemical competition on thermodynamics of bacterial adsorption. This was done using an experimental system consisting of Mendon silt loam soil as the adsorbent, Staphylococcus aureus as a common adsorbate and sodium chloride (NaCl), sodium lauryl sulfate (SLS), and peptone as competitive adsorbates.

The bacterial adsorption on soil both with and without chemical competition followed Langmuir type isotherms. From the equilibrium data, thermodynamic functions such as free energy, ΔF°, enthalpy, ΔH°, and entropy, ΔS°, were calculated. Observed positive ΔH° values indicated that the bacterial uptake in both noncompetitive and competitive …

Transpiration And Dry Matter Response To Atmospheric Humidity, Matric Suction, And Fertility, Gordon Edgar Warrington

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Growth chamber studies showed that a relationship exists between transpiration and dry matter production of spring wheat (Tritiaum Aestivum L. var . Thatcher). A temperature of 27 C for a 16-hour day,and 21 C at night were used throughout the experiment. Relative humidities (RH) of 12, 25, 71, and 83 percent and matric suctions of 1, 3, and 9 bars were used a l ong with six fertility levels and a 20-day growing period. An equation was developed from previous equations by De Wit and Arkley to describe the transpiration ratio (Tr = mass of water transpired/mass of dry …

A Kinetic Approach To The Inactivation Of Zinc By Various Soil Constituents, Shingara S. Sandhu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The adsorption reaction of zinc onto prochlorite, pyroxene, and biotite minerals, from dilute solution (water) was studied under isothermal conditions by agitated nonflow experiment method. The equilibrium concentration of zinc in the solution was determined both by radioactive tracer technique and adsorption spectrophotometer methods. The data were collected at three temperatures.

The data were treated by the equation:

∂θ/∂t = k₁(1-θ)C - k_-1θ

where θ is the fraction of total surface coverage and C is the equilibrium concentration of zinc in solution, k₁ and k_-1 are the rate constants for the adsorption and reverse …

Salinity And Water Potential Sensor For Evaluation Of Soil Water Quality, Melvin Dee Campbell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this study was to evaluate response times of a salinity sensor and a soil psychrometer. Influences of pressure, temperature and molar concentration changes were to be measured.

Salinity sensor response times ranged from 50 to 130 minutes during solution adsorption while desorption response times were perhaps ten times as long. Temperature affected both response times and equilibrium values, but pressure did not affect either.

Soil psychrometer response times ranged from from 40 to 80 minutes for either adsorption or desorption of solution. However, other factors probably related to indirectness of measurement made the soil psychrometer fail to …

Catalytic Effect Of Soil Components On The Nitrite Transformation In Buffer Acid Solutions, Laxman G. Kuratti

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrite decomposition in buffer solutions of pH 3, 4, and 5 was observed to be a first order reaction with rate constants (k) 6.39 x 10^-3, 1.15 x 10^-3, and 0.17 x 10^-3, respectively. When 10 grams of two different soils were introduced, the reaction was catalyzed in all three pH conditions studied. This effect, however, was more pronounced in pH 5.

When 10 grams of soil were introduced, all the added nitrite was not recovered. The deficit ranged from 17 to 30 parts per million when 150 parts per million nitrite nitrogen was …

A Formula To Express Evapotranspiration As A Function Of Soil Moisture And Evaporative Demands Of The Atmosphere, Aldo L. Norero

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mathematical expression was developed and tested which describes the relation between evapotranspiration and soil moisture. A general premise of this mathematical model is that the evapotranspiration-soil moisture relationship is determined by interaction of climatic, soil and plant factors. The basic model is

dETa/dYs = -ke[1-(ET_a/ET_mx)]

in which ET_a is the actual evapotranspiration, Ψ_s is the total soil water potential, k is a proportionality coefficient, ∈ is the soil moisture extraction capacity of the atmosphere , and ET_mx is the evapotranspiration that would occur from a particular crop-soil unit when soil moisture was …

Experiments On The Inactivation Of Zinc By The Mineral Fractions Of The Soil, John J. Hassett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Zinc deficiency, in many cases, is closely related to organic matter decomposition. DeRemer and Smith (1964) studied the effects of decomposing sugar beet tops on the reactions of Zn⁶⁵ in a Portneuf soil. They found that with time the Zn⁶⁵ associated with lime minerals, exchangeable, and water soluble fractions of the soil decreased, while that found with the organic and mineral fractions increased. This increase in the mineral fraction is of particular interest, since the majority of the Zn⁶⁵ was found to be with this fraction after a period of time. They also showed that the increase …

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 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 J_w, flux of solute J_s , 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:

J_w = L_wwV_w∆p + L_wsRT ln …

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(μ_w)_T / dlnT

where …

The Influence Of Irrigating With Saline Water On The Energy Status Of Water In Soil And Plant, Rolando H. Braun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

1. Changes in the energy status of water that occurred in Milville silt loam and in bean (Phaseolus vulgaris L.) plants growing on it , during two consecutive 6-day periods while being irrigated with saline solutions, were studied.
2. Total soil water potential (Ψ soil) (measured with thermocouple psychrometers), matric-potential (Ψ_m) (measured with tensiometers) were considered. In leaf samples, the total water potential (leaf) and the osmotic potential (Ψ_π)--after freezing-- were determined with thermocouple psychrometers; by difference, the pressure potential (Ψ_p) was obtained.
3. There is no evidence of close relationship between changes taking place in …