bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Thermoelectric Method for Determining the Rate of Water Movement in Plants
Authors: Bloodworth M. E. , Page J. B. , Cowley W. R. 
Published: July 2010

AbstractA thermoelectric method is described for the measurement of stream flow rates in the stems of plants. It has a definite advantage in that repeated measurements can be made on the same plant without damage to it. The method is quite simple and usually requires about 15 minutes for each measurement.By subjecting cotton plants to different environmental conditions such as temperature, humidity, and wind velocity, it was found that the rate of water uptake and movement in the stem dropped from 114 cm./hr. to 76 cm./hr. when the wind velocity was changed from high to low. A temperature of approximately 99°F. and 20% relative humidity was maintained in both cases. With no wind movement but having a temperature of 82°F. and 62% relative humidity, the rate of water movement for the same plant was 38 cm./hr.Present data show that this method is well adapted for indicating the effects of micro‐climate, soil moisture availability, and soil aeration upon the rate of water uptake and movement within intact plants. In addition, it has other uses which will be of interest to both the soil scientist and plant physiologist.
Zinc Solubility Under Alkaline Conditions in a Zinc‐Bentonite System
Authors: Jurinak J. J. , Thorne D. W. 
Published: July 2010

AbstractThe possibility of zincate formation in alkaline soils has been investigated. Utah bentonite suspensions were titrated to ½, 1, and 2% of their base‐exchange capacities with Zn65 in zinc chloride. The pH of the suspensions was varied by treatment with sodium, potassium, or calcium hydroxide. After a period of shaking, the suspensions were centrifuged and the supernatant liquid analyzed for Zn65.In both the sodium and potassium systems, zinc solubility reached a minimum in the pH range of 5.5 to 6.7. As the alkalinity of the systems was increased, the solubility of zinc also increased. This suggests the formation of soluble alkali zincates. In the calcium system, zinc solubility reached a minimum at a pH of 7.6, and no increase in soluble zinc was noted as the pH of the system was increased. The formation of insoluble calcium zincate can be postulated. Since analyses did not reveal the ionic species of zinc in solution, this study can only be regarded as circumstantial evidence in support of zincate formation in alkaline soils.The movement of various ionic forms of zinc was observed in a column of calcareous silty calay soil. Zn65 was applied to the surface as the zinc ion, the zinc‐ammonia complex, and the zincate anion at a rate equivalent to 50 pounds zinc per acre 6 inches. The columns were then leached with 18.6 inches of water. The zincate complex moved the furthest, being found at a depth of 3 cm.; the zinc ion and the zinc‐ammonia complex both moved to a depth of 2 cm. The difference in movement was attributed to the difference in sign of charge between the zinc treatments.
The Effect of Time of Top‐Dressing on Uptake of Phosphorus and Potassium by an Established Stand of Alfalfa
Authors: Seay William A. , Weeks M. E. 
Published: July 2010

AbstractPlots of established alfalfa were top‐dressed with radioactive superphosphate and half the plots received potash. Top‐dressing dates varied from September to the following June. Entire plants were sampled at various periods after top‐dressing and divided into tops, crowns, and roots for analyses.Conclusions were (1) P and K are translocated to crowns from roots and tops during autumn, (2) top‐dressed P is taken up by alfalfa even in the winter or dormant season, (3) in spring a rapid translocation of P and K from roots and crowns to tops occurs, (4) K fertilization does not affect P uptake from soil by alfalfa, (5) P fertilization does not significantly affect K uptake from soil by alfalfa although trends are more suggestive than the effect of K fertilization on P uptake, and (6) top‐dressed P was taken up to a greater extent from Hagerstown silt loam than from Nicholson silt loam which was expected in that chemical soil tests showed more available P in the Nicholson.
Effect of Soil Temperature and Soil Moisture on Manganese Absorption by Soybean Plants
Authors: Mederski H. J. , Wilson J. H. 
Published: July 2010

AbstractPeriodic field observations of the development of manganese deficiency symptoms in soybeans indicate that soil temperature and soil moisture may influence manganese absorption by soybean plants. These observations were explored in detail in a greenhouse study.Glazed pots were filled with a manganese deficient clay soil, placed in constant temperature water baths and planted to soybeans. One bath was maintained at 15° C., a second at 27° C., while the third was maintained at 15° C. for the first 7 weeks of plant growth and increased to 27° C. for the remaining 5 weeks of growth. Two soil moisture levels were provided at each soil temperature.A low soil temperature combined with high soil moisture was conductive to the development of severe foliar sympoms of manganese deficiency. High soil temperature combined with low soil moisture produced plants which exhibited only a slight manganese chlorosis. The total manganese per plant and the manganese concentration within the plant were significantly greater at the high than low soil temperature. In a solution culture study, increasing the temperature of the solution increased the manganese concentration in the soybean leaves indicating a physiological response of the plant to a change in root temperature.
The Response of Alfalfa to Borax Fertilizer on Illinois Soils
Authors: Russel D. A. , Kurtz L. T. , Melsted S. W. 
Published: July 2010

AbstractA 2‐year study was made of the response of alfalfa to varying rates of borax fertilizer applied to Illinois soils. Fourteen locations differing in water‐soluble boron content, in soil type, and in the type of legume grown were selected; the trials at five of these locations were continued the second year. Borax fertilizer was applied in the spring of the first year (1952) on established legume stands at the rate of 0, 30, 60, and 90 pounds per acre. A randomized blocks design of nine replications was used in measuring the effect of the borax treatment upon seed yield, hay yield, and leaf‐to‐stem weight ratios. A modified Berger‐Truog quinalizarin procedure was used in measuring the water‐soluble boron content of the soils. Details of the modification are given.On soils with low available boron tests, the observed deficiency symptoms were corrected by the applied borax fertilizer. Except for one location, hay yields were not significantly increased by the removal of the deficiency symptoms through borax fertilizer treatment. Seed yields were obtained at only one location, but the data for both 1952 and 1953 indicated that maximum seed production was not obtained even with a 90‐pound borax fertilizer treatment. Leaf‐to‐stem ratios, measured only in 1953, showed some variation with the rate of treatment but the data were not adequate to warrant any conclusions regarding the effect of borax on hay quality.The general conclusion was that many of the soils in Illinois are at a stage of boron indigence at which boron deficiency symptoms are produced readily, especially under climatic extremes. In only a relatively few cases are the soils low enough in available boron to reduce the yield of alfalfa hay.
Factors that Influence Loss of Fall Applied Fertilizers and Their Probable Importance in Different Sections of the United States
Authors: Nelson L. B. , Uhland R. E. 
Published: July 2010

AbstractThe purpose of this paper is to attempt to reconcile observed differences in effectiveness of fall versus spring applied fertilizers between states, and to point out factors that influence loss of fall applied fertilizers and their probable importance in different parts of the United States. Particular emphasis is placed on nitrogen fertilizers.Possibilities for leaching losses from fall applied fertilizers are evaluated from the standpoint of percolation of water from the soil in various areas and temperatures as they relate to conversion of ammonia‐nitrogen in fertilizers to leachable nitrate forms. On this basis, it appears that leaching losses would be negligible in the plains states and parts of Minnesota and Iowa. Progressing eastward, leaching from most soils is likely to increase, and fall applied nitrogen becomes questionable. In the South, where high percolation and temperatures predominate, fall application appears inadvisable.Possibilities for losses from fall application are also discussed from the standpoint of erosion losses, volatilization of nitrogen, and immobilization and reversion of nutrients.
The Use of Soil Survey Information in an Area of Rapid Urban Development
Authors: Robinson Glenn H. , Porter H. C. , Obenshain S. S. 
Published: July 2010

AbstractUrban, as well as rural planning, are necessarily influenced by certain soil properties such as drainage, permeability, type of parent material, soil texture, and depth to bed rock, water table, or an indurated horizon. These properties affect both sanitary measures and development costs. Information concerning soil characteristics of an area is contained in, or can be interpreted from, a soil survey map and report.The Fairfax County (Virginia) soil survey is being made largely because of requests from the Fairfax County Planning Commission, a commercial planning firm, and a real estate agent. Local funds are made available to the Virginia Agricultural Experiment Station to defray a part of the costs. The Planning Commission and the commercial planning firm consider soil survey information vital for preparing an overall or master plan for Fairfax County. They feel that it is especially useful in zoning, planning septic tank sewage disposal systems, and agricultural planning, and that the same information is also useful in planning highways, recreational areas, and in arriving at equitable tax adjustments. If this survey meets their expectations in helping them answer questions related to rural and urban planning, it may lead to increased future demands for soil surveys.It is desirable that persons trained in soil classification, management, and interpretation assist the various users of soil surveys. This assistance can be provided by personal consultation and carefully prepared descriptive legends and reports to accompany the map. The reports should include examples of how soils can be grouped for special purposes.The expanding use of soil surveys presents a challenge to the soil scientist. It emphasizes the need for adequate classification of soils, closer field observations, improved field techniques, basic research, and careful interpretation of data.
Houston Black Clay, the Type Grumusol: I. Field Morphology and Geography
Authors: Templin E. H. , Mowery I. C. , Kunze G. W. 
Published: July 2010

AbstractIn most characteristic form the profile of Houston Black clay (the type specimen of the new group of Grumusols as proposed by Oakes and Thorp) consists of a (1) a very thick, much darkened, uneluviated A horizon of black calcareous clay 2 to 4 feet chick, (2) a slightly darkened transition several feet thick, and (3) substratum of marine clay or marl. Thickness of the black layer varies between ½ and 5 feet with position in the original pit‐and‐mound gilgai microrelief. All parts of the solum are equally clayey and, where exposed to thorough drying and moistening without confinement of volume, naturally crumble to a mulch of discrete grains. Volume change on moistening, plasticity, and stickiness approximate the maximum that occurs in soil. Free carbonates are present but lowest in the upper few feet, intermediate in total amount but partially segregated into concretions between depths of about 3 and 8 feet, highest in the relatively unaltered substrata.This soil type, with an aggregate area of some 2½ million acres, is the most extensive of its kind in the United States and exemplifies the blackest, most plastic, and more crumbly (self mulching) variety of neutral to calcareous dark clay soils high in montmorillonite. Developed under prairie vegetation on smooth erosional upland in moist‐subhumid parts of the Gulf Coastal Plain, its occurrence is confined to outcrops of argillaceous limey rocks and related to a climate that gives alternating moistening and desiccation of the profile to depths of as much as 10 feet. Relations to some of the important closely related soil series are given. Total extent of such dark clays in the United States is a minor fraction of that in some tropical countries.
Fertilizer Evaluation: I. Fundamental Principles
Authors: Black C. A. , Scott C. O. 
Published: July 2010

AbstractEvaluation of different fertilizer sources of a common nutrient is discussed in relation to the principles of quantitative biological assay. Criteria for examining the comparative effects of different fertilizers are described. Fertilizer effects are classified into different categories on the basis of these criteria. An approach is described for extending the methods of classical biological assay to cover certain practical cases that do not meet the theoretical requirement.
Ages and Development of Soil Landscapes in Relation to Climatic and Vegetational Changes in Iowa
Authors: Ruhe R. V. , Scholtes W. H. 
Published: July 2010

AbstractRadiocarbon dates in Iowa indicate that specific upland soil landscapes can be referred to age ranges before present of: (1) > 25,000 years, (2) 16,000 to 24,000 years, (3) 14,000 to 16,000 years, (4) 12,000 to 13,500 years, and (5) < 11,000 years.Paleofloras associated with the radiocarbon horizons as well as fossil pollen sequences of geologically correlative peats permit inferences regarding the vegetative and climatic environments relative to time of the specific upland soil landscapes. In Late Sangamon time (> 25,000 years) the soil landscapes were dominantly forested under a cool, moist climate. Forest dominated the landscape during Wisconsin time (24,000 to 11,000 years) under cold, moist glacial climatic regimes and cool, moist intraglacial intervals. A warmer grassland environment may have occurred in mid‐Wisconsin time (15,000 to 13,500 years). A cool, moist, arboreal environment may have culminated approximately 5,000 years ago. A warmer, subhumid to humid prairie environment became dominant at that time.Such complex climatic and vegetative histories of soil landscapes relative to time should be considered in soil‐genesis studies in Iowa as well as in other similar areas.
Effect of Nutrition on Trifolium hirtum Inoculated with Rhizobium trifolii
Authors: Specht Alston W. , Erdman Lewis W. , Means Ura Mae , Resnicky John W. 
Published: July 2010

AbstractThe growth and chemical composition of Trifolium hirtum plants inoculated with effective strains of Rhizobium trifolii and grown in sand cultures in the greenhouse were studied in two experiments. In the first, element ratios remained constant, but a complete nutrient solution of three concentration levels with and without supplementary nitrogen was used. In the second experiment, two levels of supply each of potassium, calcium, and magnesium were used without supplementary nitrogen in a 2 × 2 × 2 factorial experimental design.The highest yields in the two experiments were obtained in the first one when supplementary nitrogen was supplied to the plants in the nutrient solution. This indicated that in these experiments maximum yields were not possible with symbiotically fixed nitrogen alone. The data also indicate that symbiotic nitrogen fixation and yield of T. hirtum are closely related to the interrelation of the levels of supply of potassium, calcium, and magnesium. The results of these experiments show that this plant is very sensitive to its nutrient supply, and this characteristic suggests a delicate nutrient‐balance requirement to achieve the most efficient symbiotic nitrogen fixation and the best crop yields.
The Application of the Mitscherlich Equation for the Calculation of Plant Composition Due to Fertilizer Increments
Authors: Balba Monem A. , Bray Roger H. 
Published: July 2010

AbstractThe equation introduced by Mitscherlich has been generally used to express nutrient‐yield relationships as follows:y = A(1—e‐eb‐ex)This paper reports an attempt to apply such a curve to soil nutrient‐plant composition relationships, using the wheat plant. For this study soils deficient in phosphorus were selected in four different soil areas. All nutrients were supplied in adequate amounts except phosphorus which was added in five increments as superphosphate (0‐45‐0).Wheat grain was analyzed for phosphorus and the constants for the above equation, after Bray's modification, were established. The equation arrived at wasy = 0.5834 (l—e‐0.03296b‐0.002097x)where y is percent phosphorus in the grain, in the presence of x pounds of P2O5 and b pounds of soil phosphorus as determined by the soil test.The equation, besides expressing quantitatively the soil nutrient‐plant composition relationship, may provide a means to differentiate between the amount of the nutrient taken up by the plant from the soil sources and that from the added fertilizer sources. The relative magnitude of the efficiency factors may be considered as a quantitative measure for the net relative availability of the nutrient forms involved. It may serve to predict the soil phosphorus level through the plant composition or vice versa.
Crop Response to NPK Fertilizers Varying in Granule Size and Water Solubility of the Phosphorus
Authors: Terman G. L. , Anthony J. L. , Mortensen W. P. , Lutz J. A. 
Published: July 2010

AbstractCrop response to 7‐14‐14, 6‐12‐12, 10‐20‐20, and 11‐22‐22 fertilizers was determined on 5 soils in 2 greenhouse experiments in Tennessee and Virginia and in 21 field experiments in Georgia, Kentucky, Mississippi, North Carolina, Tennessee, and Washington. All soils were acid to neutral in reaction. The fertilizers, separately formulated from dicalcium phosphate, ammoniated ordinary superphosphate, ammoniated concentrated superphosphate, and diammonium phosphate, had 7, 27, 60, and 100%, respectively, of the phosphorus in a water‐soluble form. Each fertilizer was granulated and screened into 6–14, 14–35, and −35 mesh sizes. Early growth response, as determined in the greenhouse with oats and Sudangrass, and in the field with wheat forage and other crops, increased with smaller granule sizes of the low water‐soluble fertilizers but decreased with smaller granule sizes of the high water‐soluble fertilizers. This pronounced interaction of water solubility and granule size found at early growth stages did not persist in final yields of corn or wheat grain and vegetables in most experiments. Where an early growth response is desired, results indicate that fertilizers having a low water‐soluble phosphorus content should be granulated more finely than those having a high content of water‐soluble phosphorus.
Ion Absorption by Corn Roots as Influenced by Moisture and Aeration
Authors: Danielson R. E. , Russell M. B. 
Published: July 2010

AbstractUsing short‐term experiments, the uptake by corn seedlings of Rb86 from soil and from osmotic solutions has been measured under various levels of moisture stress and oxygen pressure. Soil moisture tensions, up to 12 atm., were developed using pressure plate apparatus appropriate to the tensions desired, and the osmotic studies were conducted with a highly porous, expanded perlite material wetted with aqueous solutions of mannitol. Continuous flushing with gas mixtures of air and nitrogen was used to maintain the oxygen partial pressures desired.Moisture stresses developed from soil moisture tensions and from osmotic solutions differed markedly in their effect on Rb86 absorption. The ion uptake decreased rapidly with initial increases in soil moisture tension and leveled out at higher tensions to give a curve nearly logarithmic in nature. Increasing osmotic pressure caused only a slight decrease in absorption of Rb86 by the corn seedlings. The ion uptake from soil was nearly a straight line function of moisture content.Initial increases in oxygen concentration of the gaseous environment at each level of soil moisture tension or osmotic pressure resulted in increased uptake of Rb86. In soil, however, the minimum oxygen content at which ion absorption reached a level value decreased with increasing soil moisture tension.
Measurement of Water and Air Permeability in Unsaturated Soil
Authors: Corey A. T. 
Published: July 2010

AbstractEquipment developed for the measurement of oil and gas flow in oil producing sands was used to study unsaturated permeability in a soil. The method employs the simultaneous flow of air and water under the same pressure gradient to maintain a uniform tension and, as a consequence, a uniform saturation within the sample during permeability measurements. The saturation is reduced in increments by reducing the water pressure with respect to the air pressure.Results of unsaturated permeability measurements on two relatively undisturbed samples of a sandy soil are presented. The interrelationship between gas and liquid permeabilities as a function of saturation is discussed, and a method of calculating the unsaturated water permeability from the more easily measured air permeabilities is suggested. The magnitude of gas slippage in a dry soil sample was determined by measuring the air permeability at several mean pressures and extrapolating the air permeability‐mean pressure function to an infinite pressure. The permeability to water of the saturated soil was only about half the permeability to air of the dry soil even when the air permeability was corrected for slippage.
Use of Thermistors for the Measurement of Soil Moisture and Temperature
Authors: Bloodworth M. E. , Page J. B. 
Published: July 2010

AbstractBasic information on soil moisture availability for proper plant growth and development is essential in irrigated areas. This has practical applications for determining the rate and zone of moisture use by plants as well as the over‐all irrigation requirements of crops.It has been recognized that the thermal method of soil moisture measurement offers one of the best possibilities of being unaffected by salt in addition to covering the available moisture range with acceptable sensitivity. By using a thermistor as a combination heating element and temperature indicator, it has been found that such a unit, when cast in a porous material, serves as an accurate moisture indicating device.Laboratory experiments have indicated that this method of moisture measurement covers the available moisture range, with its greatest sensitivity near and below field capacity. The thermal units have been unaffected by salt concentrations normally found in agricultural soils.