bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soils of the Rio Grande Valley Border in Southern New Mexico
Authors: Gile Leland H. 
Published: July 2010

AbstractMany kinds of desert soils occur along the border of the Rio Grande Valley in southern New Mexico. These include series in the Torripsamments, Torriorthents, Camborthids, Haplargids, Paleargids, Calciorthids, and Paleorthids. Soil morphology and distribution are related to soil age, texture of parent materials, present and past climate, soil biota, geomorphic surface, and degree of landscape stability. Increase in soil development with age is shown by increasing carbonate accumulation, by increasing silicate clay accumulation in some soils, and by increasing thickness of solum.Radiocarbon ages of buried charcoal show that some soils are of Holocene age while others are much older and started their development at various times in the Pleistocene. Morphology of the Holocene soils indicates present processes of pedogenesis in this desert region. Certain morphological similarities of Holocene soils to those of Pleistocene age also suggest the character of present processes of pedogenesis in soils that started their development in the Pleistocene. The illuviation of carbonate in nearly all soils and the illuviation of silicate clay in some soils are features of pedogenesis at the present time.The argillic horizons have been turncated in many soils along the valley border and in others have been engulfed by carbonate or mixed by soil biota. Horizons of carbonate accumulation in these soils are commonly compact and some are indurated, thus are more resistant to erosion and disruption by soil biota. Development of the horizon of carbonate accumulation is therefore a more reliable indicator of approximate soil age than morphology of the B horizon.Soils discussed in this report have formed in alluvial parent materials derived from noncalcareous rocks, and calcareous dust is virtually the sole source of pedogenic carbonate. Percentages of CaCO3 equivalent for such soils, as determined in the laboratory and controlled by soil morphology, are measures of approximate amounts of dust‐derived illuvial carbonate.
Preventing Water Resorption in Weight Loss Determinations
Authors: Kittrick J. A. , Hope E. W. 
Published: July 2010

AbstractAn important error in weight‐loss determination is resorption of moisture after heating. This is prevented by heating samples in glass ampules in an aluminum block. The ampules are sealed prior to cooling. The average deviation between duplicates for the procedure is ± 0.03% weight loss, or less, when mineral samples are heated to 300C.Weight losses for several minerals and soils suggest that there is no single time and temperature combination best for all materials, and that heating to 110C gives incomplete weight loss.
New Occurrences of Tabular Halloysite
Authors: Carson C. D. , Kunze G. W. 
Published: July 2010

AbstractIn order to establish the presence of tabular halloysite in soils of widely distributed geographical areas, a study was made of the < 0.2µ clay fraction of four soils. This relatively new clay mineral was found in the Weston soil series from Florida and the Chicaj series of Guatemala. These two soils along with two series from Texas already known to contain tabular halloysite showed the mineral to have moderately high surface areas and cation exchange capacities. Chemical analyses show significant quantities of Mg and Fe present. Upon examination by X‐ray diffraction all clays showed a 7.4A peak characteristic of this clay mineral.
Effect of Temperature on Shear Compliance of Soil with Isosteric Water Vapor Adsorption
Authors: Waldron L. J. , Constantin G. K. 
Published: July 2010

AbstractShearing deformation of a soil briquet with equal amounts of adsorbed water at 35.5 and 44.5C was measured from 1 to 86,400 seconds. Deformations at 1 second were the same for both temperatures, but deformation continued at a higher rate thereafter at the higher temperature. The difference in deformation rate at the two test temperatures is greater than the change in fluidity of bulk water at the two temperatures. The isosteric heat of adsorption at the particular water content (equivalent to about 10 monolayers) was about 10% greater than the heat of condensation of water.
Thixotropic Changes with Aging of Synthetic Soil Aggregates
Authors: Blake G. R. , Gilman R. D. 
Published: July 2010

AbstractArtificially prepared aggregates held at constant water content increased in relative stability with time. The increase is analogous to a thixotropic sol‐gel transformation and to an increase in strength of packed soil with aging. Aggregates were not perceptibly stable to wet sieving at time of formation. Matrix stability of aggregates increased at a rate dependent on water content at which aggregates were stored, on soil type and on storage temperature. High relative stabilities were commonly attained in 24–48 hours at intermediate water contents and at 25C. Extent of slaking resistance was dependent on aging from time of aggregate formation rather than from time of wetting pulverized soil in preparation for pressing into aggregates. The aging phenomenon was independent of organic matter content and of a viable microflora. Data are compatable with the explanation that orientation of water molecules and associated cation equilibrium, and spontaneous shifting of clay particles to positions of lowered potential energy account for the build‐up in aggregate stability during aging.
Desorption of Lindane from Soil as Related to Vapor Density
Authors: Spencer W. F. , Cliath M. M. 
Published: July 2010

AbstractVapor‐phase desorption of soil‐applied lindane (γ‐BHC) was studied by measuring vapor density of lindane as affected by soil‐water content, temperature, and lindane concentration. Water content had no effect on vapor density until the soil was dried to a water content below one molecular layer of water. When more than a monomolecular layer of water was present in Gila silt loam, vapor density increased with temperature and lindane concentration until a saturated vapor density, equal to that of lindane without soil was reached at 50, 55, and 62 ppm lindane at 20, 30, and 40C, respectively. Isotherms relating soil lindane concentration to relative vapor density were similar to isotherms relating soil lindane concentration to solution concentration indicating that Henry's Law, p = kc, can be used to predict pesticide behavior in the soil‐water system. Desorption isotherms for lindane on Gila silt loam and bentonite fitted the Freundlich equation. Freundlich constants for vaporphase lindane were similar to those reported previously by others for adsorption of lindane from the solution phase by soil materials.
Urea Conversion to Ammonia in Waterlogged Soils
Authors: Delaune R. D. , Patrick Wm. H. 
Published: July 2010

AbstractUrea hydrolysis to ammonia proceeded at about the same rate in waterlogged soils and in soils kept at ⅓ bar moisture. Urea hydrolysis took place at an initial rate of about 8 to 12 ppm/hour and began to level off after about 24 hours. Maximum conversion of urea occurred at about pH 8 under both moisture conditions. Volatilization loss of ammonia hydrolyzed from surface applied urea was slightly greater at ⅓ bar than under waterlogged conditions and was considerably greater under all conditions than was loss from surface applied ammonium sulfate. For topdressed urea in flooded soil, urea conversion was much more rapid in the surface layer of soil than in the flood water.
Characteristics of Boron Absorption by Excised Barley Roots
Authors: Bingham F. T. , Elseewi A. , Oertli J. J. 
Published: July 2010

AbstractBoron absorption by excised barley roots was found to be noncumulative, rapid, and unaffected by pH variations of the substrate in the acid range. However, increases in pH above 7.0 resulted in sharp reductions in absorption. At pH 6.0, changes in substrate temperature, salt composition and level, or addition of KCN and 2,4‐DNP failed to exert any influence on B absorption.These results indicate that B absorption is a physical, non‐metabolic process acting in response to B concentration gradient and that molecular boric acid is favored for absorption.
Residual Effect of Grain‐Pasture Feeding Systems on the Fertility of the Soil Under a Pasture Sward
Authors: Benacchio S. S. , Baumgardner M. F. , Mott G. O. 
Published: July 2010

AbstractDuring 1967, the fertility status of the soils under pasture swards was studied after 4 years of different levels of grain feeding. Nutrient status was assessed by standard soil analysis procedures. The primary concern of this study was to examine the relationship between the amount of grain fed to grazing steers in previous years and the fertility status of the soils at the end of the 1967 growing season during which time no grain was fed to the grazing animals.A phosphorus accumulation occurred up to a 7.5‐cm depth and was linearly related to the amount of grain fed. The available potassium increased at a growing rate as the level of grain was augmented, indicating a quadratic relationship. This occurred at all sampling levels although the accumulation was much greater in the surface 2.5 cm than at lower depths. The levels of potassium in the surface 2.5 cm of soil were closely related to pasture yield. The pH negatively correlated with potassium availability in the surface 2.5 cm of soil. Potassium level in these pasture soils was a reliable indicator of the fertility value of the excreta from the grazing animal.
Autoradiographic Evidence for the Differential Effect of Four Plant Species in Altering the Calcium Content of the Rhizosphere Soil
Authors: Barber Stanley A. , Ozanne Peter G. 
Published: July 2010

AbstractChanges in the concentration of Ca in the soil about the roots of four species were observed with autoradiographic procedures. Ryegrass (Lolium rigidum, Gaud.), subclover (Trifolium subterraneum L.), and capeweed (Arctotheca calendula (L.) Levyns) all caused accumulations of Ca about the roots as more arrived by mass‐flow than was absorbed. Lupins (Lupinis digitatus, Forsk.) absorbed larger amounts and caused Ca depletion about the root. There was agreement between calculated and observed changes in the Ca concentration in the rhizosphere zone.
Ferromanganiferous Soil Concretions: A Scanning Electron Microscope Study of Their Micropore Structures
Authors: Cescas Michel P. , Tyner Edward H. , Harmer Richard S. 
Published: July 2010

AbstractThe micropore structures of zoned and nonzoned concretions which occur together in the plow‐depth layer of Flanagan silt loam were examined by scanning electron microscopy. The concretions were characterized by a dominance of small irregularly shaped pores having dimensions varying from 0.2 to 2 µ. Some large pores with dimensions of 2 to 3 µ were observed. The concretion fabric components, for the most part, were masked by massive plasmic depositions indicating that much of the original matrix porosity had probably been infilled during concretion formation. The magnitude of infilling and reduction in original matrix porosity, judged from the frequency and distribution of various sized pores, appeared to be similar for zoned and nonzoned concretions.
Observations of Certain Soil Fabrics With the Scanning Electron Microscope
Authors: Lynn Warren C. , Grossman Robert B. 
Published: July 2010

AbstractApplication of the scanning electron microscope to the study of soil fabrics is presented, and techniques of sample preparation are discussed. Photographs, exhibiting most of the magnification range of the instrument, show examples of spodic, argillic, and fragipan fabrics; an argillan and a skeletan. Particle coatings or the lack of them, interparticle bridges, and orientation of clay on structural surfaces may be observed.
Effects of Loblolly Pine Fertilization on a Piedmont Soil: Growth, Foliar Composition, and Soil Nutrients 10 Years after Establishment
Authors: Moschler W. W. , Jones G. D. , Adams R. E. 
Published: July 2010

AbstractA field study was conducted in Virginia on an infertile, upland soil in the Piedmont area to determine the response of loblolly pine (Pinus taeda L.) to surface applications of N, two phosphatic fertilizers, and dolomitic limestone. No differences in survival or growth were obtained 10 years after planting. Phosphate increased competition from fireweed (Erechtites hieracifolia) so severely the first year that height growth was significantly reduced, and the effect persisted through the second year. The P content of the foliage was increased by phosphate, while lime increased the Mg content and decreased the Mn content. A high rate of rock phosphate also decreased the Mn content of the foliage. The N, K, Ca, Cu, and Zn contents of the foliage were unaffected by fertilization or liming. The P content of the foliage did not correlate closely with tests of available P in the soil nor did foliar Ca correlate with available Ca in the soil.
Effects of Sources of Phosphorus Under Varying Soil Temperature and Moisture Regimes on the Emergence of Winter Wheat
Authors: Baker J. M. , Tucker B. B. , Morrill L. G. 
Published: July 2010

AbstractThe effects of several sources of phosphorus on the emergence of winter wheat (Triticum aestivum L.) were compared when applied in a band with the seed under controlled temperature and moisture conditions. The detrimental effects of a given fertilizer treatment on emergence increased as temperature increased from 15 to 25C. Increasing soil moisture stress from 1 to 3 bars also reduced emergence. The harmful effects of increasing the temperature from 15 to 25C were greater than the harmful effects of increasing moisture tension from 1 to 3 bars. Emergence was reduced to a much greater extent on a sandy soil than on a medium textured soil for a given fertilizer treatment. The effects of temperature, moisture, and soil texture appeared to be cumulative.Ammonium polyphosphate, ordinary superphosphate, and concentrated superphosphate had approximately equal effects on emergence and were much less detrimental than monoammonium and diammonium phosphate which were about equal. Ammonium phosphate sulfate decreased emergence to a much greater extent than any other source.Banding of concentrated superphosphate with the seed reduced emergence as much as 40% in the field. This reduced emergence, however, had no effect on yield of grain.
Preparation of Porous Ceramic Cups to be Used for Extraction of Soil Water Having Low Solute Concentrations
Authors: Grover B. L. , Lamborn R. E. 
Published: July 2010

AbstractThe ceramic cups of soil moisture access tubes were found to contribute excessive amounts of Ca, Na and K to solutions drawn through them. They also adsorbed significant amounts of P from solutions containing P.Leaching the cups with 1N HCl reduced the contamination of Na and K to acceptable levels. Calcium levels were greatly reduced but significant amounts of Ca contamination continued. Phosphorus adsorption was reduced to an acceptable level.
Steady Infiltration from Line Sources and Furrows
Authors: Raats P. A. C. 
Published: July 2010

AbstractSteady infiltration from an array of equally spaced line sources or furrows at the surface of a semi‐infinite soil profile is analyzed. The discussion is based on the assumption that the hydraulic conductivity is an exponential function of the pressure head. It is shown that, under this assumption, the matric flux potential and the stream function for plane flows satisfy the same linear partial differential equation. Explicit expressions for the stream function, the flux, the matric flux potential, the pressure head, and the total head are obtained. Some implications with regard to furrow irrigation are discussed. The solution provides a rational basis for the discussion of leaching under furrow irrigation.
Solubility and Hydrolysis of Aluminum in Soil Solutions and Saturated‐paste Extracts
Authors: Richburg John S. , Adams Fred 
Published: July 2010

AbstractThree Coastal Plains soils that had exhibited different “critical” pH values for maximum cotton yields in field experiments were analyzed for Al solubility. Fertilized soil was used to verify critical pH by a root‐growth experiment in a growthchamber and to obtain displaced soil solutions (⅓‐bar moisture) and water extracts from saturated pastes. Extracts were also obtained from saturated pastes made with 0.01M and 0.05M KCl and with 0.0033M and 0.0167M CaCl2. Solutions were analyzed for pH, Ca, Mg, Mn, K, NH4+, Al, and SO42‐; the remaining ions required for electrical neutrality were assumed to be Cl‐ and NO3‐. A computer program, involving successive iterations of numerous equilibrium equations, was used to solve for ion activities and ion‐pair concentrations, including the Al‐ion species of Al3+, AlOH2+, Al6(OH)153+, and AlSO4+. The ion‐product of (Al3+) (OH‐)3 was considerably larger and much more pH‐dependent with AlOH2+ as the hydrolytic product than with Al6(OH)153+. Calculated (Al3+) values were much lower for polymeric hydrolysis than for monomeric hydrolysis.
Reaction of Montmorillonite with Iron(III)
Authors: Herrera Rafael , Peech Michael 
Published: July 2010

AbstractThe reaction between montmorillonite and Fe(III) was studied at two different degrees of neutralization of the FeCl3 solutions. The adsorption of iron was found to reach a definite saturation value which depended on the initial degree of neutralization of the FeCl3. The maximum amount of Fe(III) adsorbed from FeCl3 solution, having molar OH/Fe ratio = 2, corresponded to the calculated amount of Fe(III) required to form a complete monolayer of octahedrally coordinated Fe(III) on both planar surfaces of the moutmorillonite. The Fe(III)‐montmorillonite complex had a net positive charge at pH 5, which decreased with increase in pH; its cation exchange capacity, however, remained constant at about 45 meq/100 g within the pH range from5 to 7.
Effect of Chemical Pretreatment of Kaolinite Clay Upon The Apparent Self‐Diffusion of Phosphorus‐32
Authors: Phillips Ronald E. , Peaslee D. E. 
Published: July 2010

AbstractIn previous work, it had been observed that “slight” differences in chemical pretreatment of kaolinite clay resulted in large differences in apparent self‐diffusion coefficients of 32P. Apparent self‐diffusion coefficients were measured in a standard kaolinite clay for differing chemical pretreatments. Elemental P was added to each treatment at the rate of 160 ppm. The clay of each treatment was the same physically, but differed chemically due to the chemical pretreatment. Large differences in apparent self‐diffusion coefficients resulted; they were significantly and linearly related to water‐soluble P. A “capacity factor” was calculated from the apparent self‐diffusion coefficients for each chemical pretreatment. The water‐soluble P contents were inversely proportional to the “capacity factors.” The data indicated that systems in which diffusion coefficients of P are measured need to be chemically characterized in detail and that the validity of measuring self‐diffusion coefficients of P in materials such as kaolinite clay needs to be critically evaluated.
Micronutrient Uptake and Mobility Within Corn Plants (Zea mays L.) in Relation to Phosphorus‐induced Zinc Deficiency
Authors: Warnock R. E. 
Published: July 2010

AbstractCorn plants (Zea mays L.) were grown in greenhouse pots on calcareous soil known to be low in available Zn. Phosphorus was applied to soil at rates of 0 to 520 ppm with concomittant addition of Zn decreasing from 40 to 0 ppm—in inverse concentration. Zinc deficiency occurred at high P and low Zn. Maximum growth occurred at 130 ppm P and 2.5 ppm Zn applied.Distribution of Zn, Fe and Mn among leaf, stem and root tissue indicated that P and Zn fertilization had altered the mobility of these micronutrients within the plant. Mobility of Fe and Mn was increased by high P and low Zn. Zinc mobility varied opposite to that of Fe and Mn.Applied P reduced Zn concentration in tissue but not uptake per plant. DTPA‐extractable Zn in soil was not decreased by P applied, but did increase with Zn applied. DTPA‐extractable Fe and Mn increased at high levels of applied P.Zinc‐deficient plants accumulated a large excess of Fe. Interference from excess Fe is suggested as contributing to physiological malfunction within Zn‐deficient corn plants.
Extraction and Colorimetric Determination of Urea in Soils
Authors: Douglas L. A. , Bremner J. M. 
Published: July 2010

AbstractA simple colorimetric method of determining urea in soils is described. The soil sample is extracted with 2M KCl containing a urease inhibitor (phenylmercuric acetate), and the extract is analyzed for urea by measurement of the red color formed when an aliquot is heated with diacetyl monoxime and thiosemicarbazide under acidic couditions (phosphoric acid‐sulfuric acid medium). The method is sensitive and precise, and it gives quantitative recovery of urea added to soils. The extraction performed is satisfactory for determination of exchangeable ammonium, nitrite, and nitrate by steam distillation methods.
Solubility and Availability of Sorbed Sulfate in Hawaiian Soils
Authors: Hasan S. M. , Fox R. L. , Boyd C. C. 
Published: July 2010

AbstractThe capacity of volcanic ash soils to adsorb sulfate is related to rainfall, a major factor in weathering. Highly weathered and leached soils developed from ash may contain 7,000 µg/g of sulfate S in the subsoil. This sulfate has very low water solubility. Some less weathered ash soils are almost devoid of sulfates. Desorption of sulfate decreases the solubility of adsorbed sulfate remaining. Sulfate sorption‐desorption isotherms plotted against log concentration of sulfate in equilibrium solutions give approximately straight lines up to 16 to 30 ppms S in solution. Indications are that “first phase” adsorption maxima were attained by highly weathered soil at about 16 ppm S in solution. For less weathered soils, “first phase” adsorption maxima were attained at about 33 ppm S in solution. Pot studies on soils which sorb much sulfate indicate that the soil solution should contain about 5 ppm SO4‐S for adequate nutrition of kikuyu grass. This corresponds to 60 to 80% of first phase adsorption maxima of the ash derived soils. Soils which have low capacity to adsorb sulfate need higher concentrations of sulfate in solution to compensate for low adsorption capacity. A soil which field experiments had shown to be very S deficient was only 10% sulfate saturated.
Phosphate Sorption Isotherms for Evaluating the Phosphate Requirements of Soils
Authors: Fox R. L. , Kamprath E. J. 
Published: July 2010

AbstractPhosphorus sorption isotherms were constructed for soils which varied in mineralogy, texture, and past history of phosphate fertilization. Equilibrating conditions were: 25C, 0.01M CaCl2, and 6 days. Effects of heavy phosphate fertilization of soils with high phosphate sorption capacities were evident in phosphate sorption isotherms 10 years later. The sorption curves were used as a basis for fertilizing soils in pots so that phosphate in soil solutions varied from about 0.01 to 1.8 ppm P. Millet (Pennesitum typhoides, var. Gahi‐1), was grown for 4 weeks. Yields approached 95% maximum when phosphate in soil solutions was adjusted to 0.2 ppm. The phosphate concentrations at which near maximum yields were attained were little influenced by soil texture or past fertilizer treatments, but absolute yields of millet growing in the sandy Norfolk soil (low phosphate buffering capacity) was greatest if the soil had been previously phosphate fertilized.