bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Moisture on the Effectiveness of Winter‐Applied Nitrogen Fertilizers
Authors: Kurtz L. T. , Owens L. D. , Hauck R. D. 
Published: July 2010

AbstractTwo field experiments were conducted to compare the effectiveness of 3 forms of N when applied in the winter to a silt loam soil receiving 3 different rates of moisture. Ammonium sulfate, sodium or calcium nitrate, and urea were applied in the winter at the rates of 0, 60, 120, and 240 pounds of N per acre. The moisture rates ranging from 9 to 29 inches were established for the 5 months between fertilizer application and crop seeding. Four forage crops were then grown successively on the plots over a period of 2 years. Yield and nitrogen contents of the crops were determined for each plot.Nitrogen contents of crops from fertilized and unfertilized plots were, in general, inversely proportional to the amount of moisture applied to the plots during the winter and spring. Crop uptake of N from plots receiving ammonium, urea, and nitrate N was generally similar at lower moisture and N rates. However, uptake was less from nitrate‐treated plots than from the corresponding ammonium‐treated plots when applications of either N or moisture were increased to high levels. Experimental conditions were probably conductive to nitrogen losses through leaching and denitrification.
Vertical Distribution of Soil Phosphorus and Potassium on Several Established Alfalfa Stands That Received Various Rates of Annual Fertilization
Authors: Wells K. L. , Parks W. L. 
Published: July 2010

AbstractAvailable soil phosphorus, available soil potassium, calcium, magnesium, and pH were determined at various depths on four soil profiles under established stands of alfalfa. Three experiments were set up in a complete factorial design using four rates of annual phosphate application and five rates of annual potash application. The fourth experiment received five annual applications of potassium and no applications of phosphate since it was on soil inherently high in phosphate.Available potassium after 4 years of annual applications of potash on three soils and 5 years on one soil was concentrated in the 0‐ to 6‐inch layer. Only a slight movement of potassium into depths below 6 inches was noted even at high rates of annual potash fertilization. Available soil phosphorus was found to be concentrated in the 0‐ to 3‐inch layer. It was found that annual potash and phosphate applications had little effect on soil reaction.Significant difference in yield at the 0.05 level of probability was found between the 0‐ and the 100‐pound‐peracre annual potash treatment in each experiment, and between the 0‐ and the 60‐pound‐per‐acre annual phosphate treatment on those experiments receiving phosphate fertilization. No significant response to higher rates of annual todressing was obtained.Yield data were correlated with soil test potassium values of various soil layers. A poor correlation was found to exist between soil test potassium values and yield. Correlation values were increased by addition of phosphorus soil test values into the equation.
Cobalt Uptake by Plants from Cobalt Impregnated Soil Minerals
Authors: Kabata Alina , Beeson Kenneth C. 
Published: July 2010

AbstractA water‐soluble Co salt applied to soils will result in a greatly increased uptake by crop plants for a short period. Although most of this Co is retained in the soil it gradually becomes unavailable and its effect may entirely disappear within 10 years. Since soil minerals are important factors in the Co supply to the soil solution the relative uptake of Co from substrates containing Co‐impregnated bentonite, kaolin, hematite and muscovite treated in a manner to exclude exchangeable Co was investigated.The highest sorption of Co was found in muscovite, but the highest percentage of sorbed Co soluble in 0.1N HCl was found in the bentonite. Ladino clover and orchardgrass absorbed several‐fold more Co from bentonite than from the other minerals, and there was a correlation between this uptake of Co and the 0.1N HCl‐soluble Co in the bentonite‐sand culture at the conclusion of the experiment. In all cases the total uptake of Co was only a small fraction of the total supply of Co in the substrate.
Release of Nonexchangeable Soil Potassium During Short Periods of Cropping and Sodium Tetraphenylboron Extraction
Authors: Scott A. D. , Welch L. F. 
Published: July 2010

AbstractUndried soils were cropped in the greenhouse to determine the short‐term release of nonexchangeable K under intensive cropping conditions. Using corn root mats with plants intact, it was found that 218, 59, 50 and −1 ppm. nonexchangeable K was released in 10 days by Marshall surface and subsoil and Clarion surface and subsoil samples, respectively, that had received no NH4 or K additions. It was concluded that this short‐term cropping method could be used to study factors that affect the availability of nonexchangeable soil K to plants.Nonexchangeable K was also extracted from the undried soils by two chemical methods that tend to reduce the blocking effect of replaced K. Single extractions with a NaOAc‐NaBPh4 solution removed more nonexchangeable K than five successive NaCl‐HCl extractions or 5‐day cropping periods. The corn plants and the NaCl‐HCl solution, however, continued to remove K when the extraction period was increased whereas the NaOAc‐NaBPh4 solution did not.
Determination of Consumptive Use of Water by Irrigated Crops in the Western United States
Authors: Robins J. S. , Haise H. R. 
Published: July 2010

AbstractCertain of the many procedures for indirect estimation of consumptive use are discussed including the Blaney‐Criddle, Thornthwaite and Penman methods as well as evaporimeters such as atmometers and evaporation pans. The applicability and limitations in use of these procedures are analyzed including type and quality of data available, microclimatic effects and use of derived information. Problems involved in determining evapotranspiration or consumptive use by irrigated crops are discussed and their implications in use of data obtained for specific situations are analyzed. These include sampling precision, frequency and time of sampling, crop rooting depth and stage of growth, type of crop, moisture status effects, climatic effects including advected heat, and percolation losses beyond the sampling zone.
Soil Tensile Strength by Centrifugation
Authors: Vomocil J. A. , Waldron L. J. , Chancellor W. J. 
Published: July 2010

AbstractTensile stress was applied to soil samples by the body force developed when they were rotated in a specially designed centrifuge head. Cylinders or briquets of soil were positioned in the head with their long axes perpendicular to the axis of rotation. The magnitude of applied tensile stress was calculated from sample dimensions, sample mass and speed of rotation. Tensile strength was defined as the applied tensile stress when the sample failed.Tests were made on samples prepared from five soil types. Three methods of preparation were used that produced samples with water contents ranging from oven‐dry to that corresponding to approximately ⅓‐atm. suction. The method proved satisfactory over this range of water contents. Experience and calculations indicated it could be used over a range of strengths from 15 to 4000 millibars. Reproducibility varied with the method of sample preparation. The coefficient of variation ranged from 10 to 25%.
The Influence of Phosphorus Fertilization and Moisture on Growth and Nutrient Absorption by Spring Wheat: II. Soil and Fertilizer P Uptake in Plants
Authors: Power J. F. , Reichman G. A. , Grunes D. L. 
Published: July 2010

AbstractThe availability and uptake of soil and fertilizer P was studied with dryland spring wheat under four moisture regimes in a field experiment in eastern Montana. The Chestnut soil used was moderately low in available P (6.2 ppm. NaHCO3‐soluble P per acre).Fertilization with P, higher soil moisture supplies at seeding time, and additional precipitation during the growing season, all increased total P uptake by spring wheat at all stages of plant growth. Interactions between any of these three factors seldom affected total P uptake at any stage of growth.Increasing the supply of soil moisture at seeding or growing‐season precipitation increased plant uptake of soil P. However, P fertilization reduced soil P uptake. Moisture supplies at seeding and growing‐season precipitation did not affect uptake of fertilizer P, except at the tillering stage of growth. The percent of total P in plant material derived from fertilizer was generally lowest in treatments receiving the most moisture, either as stored soil moisture or growing‐season precipitation. NaHCO3‐extractable P was not influenced appreciably by moisture conditions.
Greenhouse Measurement of Available Sulfur Using Radioactive sulfur
Authors: Nearpass D. C. , Fried M. , Kilmer V. J. 
Published: July 2010

AbstractAvailable sulfur was determined in a greenhouse experiment with 30 surface soils from the Southeastern United States by growing cotton plants at six levels of applied sulfate‐sulfur, 0, 2, 4, 8, 16, and 32 ppm. The A value technique involving radiosulfur was used as an index of available sulfur.Sulfur A values varied from 9.8 ppm. to 42 ppm. A high degree of correlation was obtained between A values and the percent sulfur in the control plants. Growth responses from applied sulfate‐sulfur were also related to percent sulfur in the control plants and to A value sulfur in the soil. The total uptake of sulfur also was related closely to the total available sulfur in the soil (A value plus fertilizer sulfur). A sixteen‐fold increase in the rate of sulfur addition increased the A value by approximately 20%.
Derivation of State Factor Equations of Soils and Ecosystems
Authors: Jenny Hans 
Published: July 2010

AbstractThe ecosystem is a piece of landscape having artificial boundaries. Changes in ecosystem properties are viewed as gains minus losses or influxes minus outfluxes of matter and energy. The fluxes are expressed as products of gradients and permeation. The outside potentials of the flux gradients are identified with the environmental soil‐forming factors, particularly climate and biotic factor. Pedogenic functions as now rewritten offer psychological and typographical advantages.
Runoff and Erosion Losses from Mexico Silt Loam in Relation to Fertilization and Other Management Practices
Authors: Whitaker F. D. , Jamison V. C. , Thornton J. F. 
Published: July 2010

AbstractResults from the runoff‐erosion plots on claypan soils at McCredie, Missouri, are summarized. With improvement due to fertilization and sod rotations, the performance of these soils approaches that of the better soils of Missouri. Where adequate fertility is supplied the chief advantage of growing corn in a sod‐based rotation over continuous corn is the reduction in the time the soil is without protective cover. The critical period found for erosion losses from corn was from the time of seedbed preparation until the growing crop provided an adequate canopy. Erosion losses for rotation corn were about 60% as high as for continuous corn from intense rain storms that occurred during this period. Average soil and water losses from adequately fertilized soil were less for corn in rotation than for continuous corn during the corn growing season. Seedbed preparation by subtillage so as to leave shredded cornstalks on or near the surface reduced erosion losses.
Growth and Ca Uptake by Plants as Affected by Rate and Depth of Liming
Authors: Hourigan W. R. , Franklin R. E. , McLean E. O. , Bhumbla D. R. 
Published: July 2010

AbstractThe study involved the liming of two acid soils, one high in extractable Al and one of similar pH, but low in extractable Al. Portions of each soil were treated in the laboratory with Ca(OH)2 (labeled with Ca45) to bring the pH to three levels. One of the soils also had been maintained in the field at the same pH levels for many years. Three depths of topsoil were used with corresponding depths of subsoil. These soils were placed in 18‐inch cylinders and cropped to alfalfa.Results indicated that plant yields, root proliferation, and consequent uptake of Ca depend largely on adequate level of lime in both topsoil and subsoil. However, if sufficient lime was applied to the topsoil, near maximum yields were obtained regardless of the lime level of the subsoil. Subsoil liming had minor effects on yield and uptake of Ca except when the topsoil was shallow and more acid. The soil with the highest level of Al responded proportionally more to the lime added. Freshly added Ca appeared to be more available to alfalfa than Ca added earlier in the field. The percentage of Ca from the topsoil‐applied source increased from 8 to 100% as the rate of liming increased from ½ to 8 tons per acre in a 3‐inch layer of the most acid soil. With increased level of lime in the subsoil, smaller percentages came from the Ca applied to the topsoil. Root growth generally reflected what yields and Ca uptake had indicated. Root cation‐exchange capacities increased with increased rate of liming.
A Self‐Adjusting, Null‐Point Tensiometer
Authors: Leonard Ralph A. , Low Philip F. 
Published: July 2010

AbstractThis paper describes a new tensiometer which does not allow water passage through the porous cup and which automatically adjusts the measuring manometer to the correct tension value. It can be used to measure dynamic as well as static tensions. Performance data, which are given and discussed, indicate the accuracy of the tensiometer is within 2%.
The Use of Thermometric Titrations in Soil Chemistry Studies
Authors: Ragland John L. 
Published: July 2010

AbstractIt was determined that a thermometric titration procedure could be used to obtain the cation‐exchange capacities and heats of neutralization of acid‐saturated clays. The endpoints of these titration curves were much sharper than those commonly obtained by potentiometric or conductometric methods.Cation‐exchange capacities calculated from thermometric titration curves of H‐exchanges agreed fairly well with those determined by the BaCl2‐TEA method. Heats of neutralization for Arizona, Mississippi, Southern and Utah bentonites were found to be: −13.3 ±2, −15.9 ±3, −16.1 ±1 and −15.5 ±2 kcal. per eq., respectively. The heat of neutralization of humic acid was −13.2 ±1 kcal. per eq. and that of Al‐saturated Mississippi bentonite was −5.5 kcal. per eq. The large difference in the heat of neutralization of the H‐ and Al‐saturated exchangers causes titration curves for the two to have widely differing slopes. This allows determination of the proportions of H and Al saturations of mixed H‐Al clays from the titration curves.The possible use of thermometric titrations in determining the course, mechanism and rate of a number of chemical reactions in soils is discussed and concluded to be excellent.
Measurement of Microbial Thermogenesis in Soil
Authors: Clark Francis E. , Jackson Ray D. , Gardner Herbert R. 
Published: July 2010

AbstractMicrobially induced temperature changes were measured in laboratory soil lots without vacuum insulation or adiabatic control. The instrumentation consisted of thermistors, a 52‐point stepping switch, and a bridge‐type strip‐chart recorder. The thermistors were variously positioned in soil quantities of 25 g., 3.3 kg., and 39.6 kg. The temperature changes were measured on an alluvial sandy loam, unamended or amended with either alfalfa meal or sucrose, at rates ranging from 0.1 to 1.0%. Temperature elevations of the order of 1.5°C. were observed in the 39.6 kg. uninsulated soil lots containing 1.0% alfalfa meal and 5.3°C. in 3.3‐kg. soil lots similarly amended and incubated in insulated containers. Addition of 1.0% alfalfa meal to 25 g. soil in uninsulated glass containers led to a maximum rise of 0.22°C.In other work, soil temperature values were determined in various soil lots given lesser rates of organic amendments. The data obtained show that organic residues in soil can cause local areas within which microbially induced thermogenesis is measurable for intervals of several days, or even weeks, despite the relatively high specific heat capacity and conductivity of moist soil.
Zirconium Content of Coarse Silt in Loess and Till Of Wisconsin Age in Northern Illinois
Authors: Alexander J. D. , Beavers A. H. , Johnson P. R. 
Published: July 2010

AbstractThe zirconium content of the course silt fraction of 11 calcareous Wisconsin age till samples and 13 calcareous Wisconsin age loess samples was determined by the X‐ray emission spectrograph. It was found that the mean zirconium content of the loess (0.055%) was approximately twice as high as in the glacial tills (0.022%). This difference in zirconium content may be used to help distinguish loess from till where separation is difficult by field methods and also should be helpful in soil development studies.
Effect of Prescribed Burning of Forest Litter on Total Soil Nitrogen
Authors: Klemmedson J. O. , Schultz A. M. , Jenny H. , Biswell H. H. 
Published: July 2010

AbstractThe effect of prescribed burning of ponderosa pine forest floor on soil nitrogen was investigated. Standardized soil columns were placed under the forest floor and subjected to three burning treatments: no burn, light burn, and intense burn. One‐third of the columns were removed immediately after burning, one‐third 4 months later, and the remainder 16 months later.All burning and post‐burning treatments showed net gains of nitrogen, those of no‐burn and light‐burn being greater than that for intense burning. The gain of nitrogen in the first inch of soil for the no‐burn and light‐burn treatments was 11.1 pounds per acre per year. This gain is attributed to leaching of the decomposing forest floor remaining after treatment and indicates a decomposition rate of 3.0%. The combined effects of light and intense burning reduced the nitrogen in the forest floor by 124 pounds per acre.
Adsorption and Desorption Phenomena of Sulfate Ions in Soils
Authors: Chao Tsun Tien , Harward M. E. , Fang S. C. 
Published: July 2010

AbstractFour soils, of 15 examined, exhibited much higher adsorption of sulfate than the others.Isotopic exchange studies indicated that sulfate which is retained by soils is in kinetic equilibrium with sulfate in solution. Adsorption‐desorption studies using retentive soils also indicated that sulfate adsorption is dependent on the concentration of the equilibrium solution. The adsorption phenomena could be described by the Freundlich type equation. The data thus indicated that the sulfate‐retentive soils did not possess adsorption maxima or definite anion exchange capacities, at least up to 500 ppm. S. Although certain soils were shown to have marked capacity to retain sulfate, the sulfate could be easily desorbed. As much as 45% of the sulfate initially adsorbed could be recovered in the first water extraction.The lack of adsorption maxima is in contrast to cation‐exchange reactions where more definite exchange capacities are observed. These data suggest that either anion exchange is not involved in the retention of sulfate or that other mechanisms in addition to anion exchange are involved with sulfate retention by these soils.
Decomposition of Phenoxyalkyl Carboxylic Acids
Authors: Burger K. , MacRae I. C. , Alexander M. 
Published: July 2010

AbstractThe persistence of phenoxyalkyl carboxylic acids in soil was measured by a bioassay technique using alfalfa seedlings. Acetic, alpha‐propionic and alpha‐ and gammabutyric acid derivatives were toxic when applied to soil planted to alfalfa whereas the beta‐propionic acid derivatives showed no inhibition of the test plant. All 3,4‐dichloro‐ and 2,4,5‐trichlorophenoxyalkyl carboxylic acids exhibited prolonged persistence in soil. The duration of phytotoxicity in soil receiving 4‐chloro‐, 2,4‐dichloro‐ and 2‐methyl‐4‐chlorophenoxyalkyl carboxylic acids was governed by the type and linkage of the aliphatic side chain.A Flavobacterium sp. active in the degradation of phenoxybutyric acids was isolated. The bacterium metabolized only phenoxybutyric acids having no meta chlorine on the aromatic ring. In the decomposition, the organic chlorine was liberated and the aromatic ring cleaved.The results demonstrate that specific structural characteristics of these herbicide molecules govern persistence of the compounds in soil.
A Comparison of the Amounts of Phosphorus Removed from Different Soils by Various Extractants
Authors: Breland H. L. , Sierra F. A. 
Published: July 2010

AbstractThe relative effects of 8 extractants on the removal of phosphorus from 7 major soil types of Florida were studied. HCl and NH4F and HCl and H2SO4 solutions extracted more phosphorus than the other extractants. The amount of phosphorus extracted by any of the extractants apparently depended, to a large extent, on the kind and amount of phosphorus compounds present in the soil as well as other factors. It was found that soils high in phosphorus required a longer extraction period to reach equilibrium than those low in phosphorus. Increasing the length of stroke of the shaking machine from 1½ to 3 inches did not significantly affect the amount of phosphorus removed from the soils. In general, an extraction time of 10 to 15 minutes was sufficient for the extraction of soil phosphorus.
An EDTA Method for the Direct Routine Determination of Calcium and Magnesium in Soils and Plant Tissue
Authors: Barrows Harold L. , Simpson Elmer C. 
Published: July 2010

AbstractAn EDTA procedure is described for the direct determination of Ca and Mg in soils and plant tissue. These elements are determined in the ammonium acetate leachate of soils and in the 1N HNO3 solution of the plant ash. Calcium is separated from Mg by precipitating calcium sulfate from ethanol and is determined in the precipitate. Magnesium is determined in the supernatant solution. Manganese may be present in concentrations likely to interfere with the Mg titration, but this interference is easily eliminated. The accuracy and precision of the method are well within the limits required for routine analyses.
The Effect of Rhizobial Polysaccharides on Aggregate Stability
Authors: Clapp C. E. , Davis R. J. , Waugaman S. H. 
Published: July 2010

AbstractSixteen rhizobial polysaccharides previously isolated and characterized and representing several cross‐inoculation groups were screened for aggregate stabilization effects on 10 subsoils of widely varying properties. Two additional polysaccharides of bacterial origin and three chemical compounds were included for comparison with the rhizobial products.Artificial aggregates were prepared in acrylic plastic molds under standardized moisture conditions. An ethanolwater microslaking procedure for assessing stability was used to determine relative effects between aggregating agents and soils. At the low concentrations used, several rhizobial polysaccharides were more effective stabilizing agents on most soils than either the synthetic soil conditioner or the other reference compounds. Some general comparisons relating carboxyl content and viscosity of the rhizobial polysaccharides and clay content with aggregate stabilization are presented and discussed.
Mechanisms of Urea Adsorption by Soils
Authors: Chin Wei‐Tsung , Kroontje Wybe 
Published: July 2010

AbstractPhysically adsorbed urea may be easily desorbed by dilution. Chemisorbed urea existing primarily in the form of relatively stable soil organic matter‐urea complexes may, in part, be slowly dissociated upon dilution.Differences between soil types with respect to urea adsorption were primarily related to organic matter contents. The effects of CEC, pH, and clay mineral content were found insignificant. Wet soils had a lower capacity for urea adsorption than dry soils. Considering the amounts of urea adsorbed, soils have in general a weak affinity for the urea molecule.