bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Calcium Ammonium and Calcium Potassium Pyrophosphates as Fertilizers
Authors: Lehr James R. , Engelstad Orvis P. , Brown Earl H. 
Published: July 2010

AbstractSix calcium ammonium and calcium potassium pyrophosphates were tested in the greenhouse as sources of P and N or K for two successive crops of corn forage on limed and unlimed Hartsells fine sandy loam. The fertilizers were applied as powders and as pellet‐granules; the residues of the granules were examined petrographically after harvest of the second crop.The granules were much less effective than the powders as sources of P and N for the first crop, but only slightly less effective as sources of K. The powders were nearly as effective as superphosphate as sources of P and one of the ammonium compounds was nearly as effective as (NH4)2SO4 as a source of N, but none of the K compounds was as effective as K2SO4 as a source of K.The chemical alterations of the pyrophosphates in the soil were much like those of the same compounds in water, and all the observed alteration products were pyrophosphates. Some of the pyrophosphates show promise as long‐term, slow‐release sources of P and N or K.
Aspects of Catenary and Depth Distribution of Opal Phytoliths in Illinois Soils
Authors: Jones Robert L. , Beavers A. H. 
Published: July 2010

AbstractSoil opal phytolith content is intimately related to internal soil drainage; highest opal contents occur in the middle of the drainage sequence. Soil productivity is invoked to explain the catenary opal distribution. Phytoliths are concentrated in the surface horizon of Planosols but distributed downward to 20 inches in Brunizem and Gray‐Brown Podzolic soils. Differences in chemical and catenary milieu, soil fauna, or loess depositional pattern are possible causes for depth distribution differences.
Direct Interception of Cloud Water on Lanaihale, Hawaii
Authors: Ekern Paul C. 
Published: July 2010

AbstractLanai, a relatively dry island, lies in the trade wind flow downstream from Maui and Molokai and is peculiarly adapted to a demonstration of the amount of water that can be gathered by direct interception from clouds. An observation station was established at the 2,750‐foot level on Lanaihale in July 1955, and maintained for 3 years. The water collected over the 3 years by a network of rain gauges set beneath a Norfolk Island pine tree averaged 391 inches while rainfall in the open was only 149 inches. Since the tree also intercepted some rainfall, a net of 30 inches is suggested as the annual gain from cloud water interception. A wire harp kept oriented into the wind by a vane gathered 1,706 inches of water while rainfall alone was 97 inches. The harp had a vertical silhouette 27.5 times the area of the standard rain gauge in which the catch was measured. A 15‐ to 20‐inch gain per unit vertical area exposed is suggested as the annual direct cloud interception by the harp. Identical catchers of aluminum louver mounted at several elevations up to 30 feet above the ground gave an increased catch greater than the increase of wind with elevation.
Water Storage Characteristics of Several Peats in situ
Authors: Boelter D. H. 
Published: July 2010

AbstractWater storage characteristics of the various horizons in a northern Minnesota bog were found to vary considerably with peat type. Surface horizons of sphagnum moss peat contain 0.020 g. per cc. of dry material and 95 to nearly 100% water by volume at saturation. Its total porosity consisted primarily of large pores which released 0.80 cc. of water per cc. between saturation and 0.1 bar suction.Decomposed and herbaceous peats from horizons below 25 cm. had water‐holding properties strikingly different from those of the moss peats. These materials had bulk densities of 0.24 and 0.14 g. per cc., respectively, and they contained between 80 and 90% water by volume at saturation. Their porosity, though high, consisted primarily of many small pores which are not easily drained at low suctions. They retained 65 to 75% water by volume at 0.1‐bar suction.These data show that a specific change in water table elevation in the horizons containing loose, porous, undecomposed moss peat would involve a great deal more water than the same change in horizons of more dense decomposed and herbaceous peats. Thus, the hydrologic role of any bog or bog area in a watershed will depend on the type of peat found in the organic soil profile.
The Effects of Wash Solvents on Cation‐Exchange Capacity Measurements
Authors: Frink C. R. 
Published: July 2010

AbstractThe CEC of a strong acid‐exchange resin, four clays, and several soils was determined using various cations for saturation and a wide variety of solvents for removal of the excess electrolyte. Precipitation of the salts in the solvents was avoided by using the more soluble acetates of the monovalent ions and the chlorides of the polyvalent ions, and by diluting the occluded volume of salt solution once with water to reduce its concentration to 0.1N. The CEC of the resin could then be determined equally well by Na, Ca, or Al, using water or any of eight nonaqueous solvents. The CEC of montmorillonite was found to be more dependent on the solvent used: low results with solvents of high dielectric constant could only be prevented by high speed centrifugation, while high results were obtained with acetone, t‐butanol, and dioxane owing to salt retention even after extensive washing. No evidence was found for the loss of adsorbed ions due to hydrolysis, or for the formation of basic exchange ions. One additional complication was found with soils: the NH4+ CEC was found to vary owing to the variable solubility of some ammoniated organic matter complex. A method is proposed in which the samples are washed with 0.001N solutions of the salts used for saturation. While high speed centrifugation is required, the introduction of a nonaqueous solvent is avoided, and a clay of known ionic composition results.
Contribution of Organic Matter and Clay to Soil Cation‐Exchange Capacity as Affected by the pH of the Saturating Solution
Authors: Helling Charles S. , Chesters G. , Corey R. B. 
Published: July 2010

AbstractThe effect of pH of the buffered saturating solution on the cation‐exchange capacity (CEC) of 60 Wisconsin soils was determined within the pH range 2.5 to 8.0. The relative contributions of clay and organic matter to total CEC were measured using multiple regression analyses; the independent variables were clay and organic matter contents and the dependent variables, CEC at pH 2.5, 3.5, 5.0, 6.0, 7.0, and 8.0. The average CEC of the organic matter at each pH value was 36, 73, 127, 131, 163, and 213 me. per 100 g., respectively; while that of the clay was 38, 46, 54, 56, 60, and 64 me. per 100 g. Within the limits of the standard errors of the regression coefficients, CEC of both clay and organic matter increased linearly with pH. The regression equations indicated that the mean relative contribution of organic matter to total soil CEC in this group of soils varied from 19% at pH 2.5 to 45% at pH 8.0; the mean organic matter and clay contents of the soils studied were 3.28% and 13.3% respectively. Coefficients of multiple correlation varied from 0.927 at pH 3.5 to 0.959 at pH 8.0.
Pyrolysis of Soil Organic Matter
Authors: Schnitzer M. , Hoffman I. 
Published: July 2010

AbstractOrganic matter extracted from O2 and Bh horizons of a Podzol soil was pyrolyzed between room temperature and 540°C. Samples were withdrawn at regular temperature intervals and analyzed by chemical and spectroscopic methods.The carbon content of the chars increased with temperature accompanied by a simultaneous decrease in oxygen. The chars of both organic matter preparations heated to 540°C. contained identical percentages of carbon and hydrogen but no oxygen. Some of the nitrogen and sulfur in the original organic matter was very stable and was recovered in the chars heated to the highest temperature.Phenolic OH groups were more stable than COOH groups but both were eliminated between 250° and 400°C. Both types of functional groups were more stable in the Bh horizon organic matter than in O2 horizon organic matter, apparently because the former was more aromatic.The infrared spectra of the chars were in general agreement with the chemical data. On the basis of the analytical data the low temperature peaks in the DTG curves of both organic matter preparations were due mainly to the elimination of functional groups, whereas the high‐temperature maxima resulted from decomposition of the nuclei.Using the graphical‐statistical method of Van Krevelen, the main reactions governing the pyrolysis of O2 horizon organic matter were found to be: (a) dehydrogenation (up to 200°C.); (b) a combination of decarboxylation and dehydration (between 200 and 250°C.); and (c) continuous dehydration. The main reaction determining the pyrolysis of Bh horizon organic matter was dehydration.
Mechanisms Involved in Soil Aggregate Stabilization by Fungi and Bacteria
Authors: Harris R. F. , Chesters G. , Allen O. N. , Attoe O. J. 
Published: July 2010

AbstractMicrobial mechanisms of soil aggregate stabilization were investigated as a function of microbiological and water‐stability changes of incubated artificial aggregates, 2 to 4.76 mm. in size composed of soil particles < 0.5 mm., prepared from Waupun silt loam. Aggregate water‐stability was determined by wet‐sieving and expressed as the percentage of soil material bound into water‐stable aggregates 0.5 to 1 mm., 1 to 2 mm. and > 2 mm. in size. Microbial development was investigated by dilution plate and microscopic methods.Aggregate stabilization was a function more of microbial synthesis of soil‐binding substances than of numbers of microorganisms. Extensive production of mycelium and spores in soil aggregates by a fungus known to be capable of aggregate stabilization, did not, necessarily, result in an increase in the stability of the aggregates. Stabilization of aggregates by Mucor silvaticus involved the binding of soil particles into > 2 mm. water‐stable aggregates at all stages of incubation. Aggregates stabilized under anaerobic conditions exhibited a high percentage contribution of 0.5‐ to 1‐mm. and 1‐ to 2‐mm. aggregates to total stability in the early stages of incubation. A relatively high proportion of the total water‐stability of sucrose‐amended aggregates possessing the indigenous mixed microflora was attributable to stable 0.5‐ to 2‐mm. aggregates in the early stages of aerobic incubation, an indication that bacteria were more important than fungi in the initial stabilization of these aggregates.
Partially Acidulated Rock Phosphate as a Source of Phosphorus to Plants: I. Growth Chamber Studies
Authors: McLean E. O. , Wheeler R. W. 
Published: July 2010

AbstractRock phosphate was acidulated with H3PO4 at 0, 10, 20, 50, and 100% of that required to convert the rock phosphate to triple superphosphate. These materials plus a check (0 P) and H3PO4 alone were established as treatments on an acid soil (AB‐38) in 1‐gallon containers in a growth chamber. Representative treatments were also made to a Miami (County) soil. The phosphate treatments were applied both in bands and mixed with the soil. In general, German millet and alfalfa yielded about as much and contained as much P in the tissue from 10% acidulated phosphate as from 100% acidulated.Corn seedlings took up P in proportion to the relative solubilities of rock phosphate, FePO4, AlPO4, Ca3(PO4)2, and KH2PO4 in sand. Yet they took up much less P when the phosphates were added to the soil, the amount being nearly constant regardless of the phosphate source added. This seems to be evidence for depression by common‐ion action of the availability of P in comparatively insoluble phosphates whether added to or formed in the soil.Plant response to the partially acidulated phosphates and to H3PO4 was discussed in the light of recent reports on phosphate reaction products in the soil. This led to the suggestion that detrimental effects of the common ion may be minimized by the partial acidulation treatments such that the environment for the soluble phosphate may be largely defined by the unreacted rock phosphate.The comparatively favorable plant response to the partially acidulated material and the economy of its production make partial acidulation appear to have very promising practical applications.
Soil Nitrogen Loss as a Result of Alternate Submergence and Drying
Authors: Patrick Wm. H. , Wyatt Ronald 
Published: July 2010

AbstractSuccessive cycles of submergence and drying resulted in the loss of 15 to 20% of the total soil nitrogen. Nitrogen was nitrified during the aerated portion of the cycle and lost when the soil was submerged. Most of the loss occurred during the first three cycles of submergence and drying. The soil oxidation‐reduction potential decreased rapidly after the initial submergence. The more times the soil had been submerged and dried, the slower the oxidation‐reduction potential decreased when the soil was again submerged. Carbon and nitrogen were lost in approximately the same ratio that they occurred in the soil.
Effects of Liming on Yields and Composition of Heavily Fertilized Grasses and on Soil Properties Under Humid Tropical Conditions
Authors: Abruña Fernando , Vicente‐Chandler José , Pearson Robert W. 
Published: July 2010

AbstractHeavily fertilized tropical grasses responded strongly to liming on two typical soils of the Humid Tropics. Liming increased the Ca and decreased the Mn content but did not affect the phosphorus or Mg content of the grasses. Surface applications of limestone were as effective as mixing limestone with the surface soil and one application was as effective as two applications at 2‐year intervals.Exchangeable Al and Mn content of the soils was sharply increased by fertilization alone but was decreased by liming. Base content at all depths sampled was decreased by fertilization alone but was increased by surface liming followed by heavy fertilization. Yields of grasses increased markedly with pH of the upper 6 inches to about 4.8, with bases to 8.0 me. per 100 g. of soil and with decreasing exchangeable Al to 2 me. per 100 g. of soil.Heavy fertilization of grasses over a 4‐year period without liming greatly depressed yields of subsequently planted tobacco and this effect was only partly compensated by reliming prior to planting the tobacco.
Soil and Plant Potassium as Affected by Soil Temperature Under Controlled Environment
Authors: Weber J. B. , Caldwell A. C. 
Published: July 2010

AbstractStudies on the effect of soil temperature and moisture on the K‐supplying power of two soils were carried out in a growth chamber. Air temperature and lighting were programmed to follow a constant daily cycle, while soil temperature was kept constant with an insulated water bath assembly. Soil and plant K determinations were made at each of five stages of growth. Regression and correlation analyses were performed to describe the various response curves. Correlations were also made to describe the relationships between the plant and soil K measurements.Results obtained from these studies showed soil temperature to have a tremendous effect on the K‐supplying power of a Floyd soil and much less of an effect on a Milaca soil. Plant yields were increased similarly on both soils with increased soil temperature, but K yields on the Floyd soil were increased from two to three times those of the Milaca soil. A significant response to applied K was obtained on both soils at low soil temperatures, but only the Milaca soil showed a substantial response at the high soil temperature. Correlations between plant and soil K measurements indicated that plants on the Milaca soil utilized exchangeable K at both low and high soil temperatures, whereas those on the Floyd soil utilized exchangeable K at low soil temperatures, and both exchangeable and nonexchangeable forms at high soil temperatures. Both soils fixed substantial amounts of applied K, but temperature effects on the two soils were very different and it appeared as though different fixation processes were involved. It was concluded from these studies that the erratic response to K fertilization on the Floyd soil in different years can be attributed primarily to differences in soil temperatures. Yield increases from K applications were obtained on this soil at low temperatures but not at high temperatures.
Morley and Blount Soils: A Statistical Summary of Certain Physical and Chemical Properties of Some Selected Profiles from Ohio
Authors: Wilding L. P. , Schafer George M. , Jones R. B. 
Published: July 2010

AbstractStatistics including the mean, range, coefficient of variation, and standard deviation are reported for particlesize distribution, organic matter content, calcium carbonate equivalent, pH, depth of leaching, soil color, grade of soil structure, horizon thickness, and depth to mottling for 21 Morley and 38 Blount soil profiles sampled in Ohio. Of these properties, composite horizon thickness, hue and value variables of color, depth of leaching of free carbonates, silt content, and total clay content are least variable. The number of profile samples required to estimate the population mean of the above parameters within ± 10% using a .95 confidence interval was also computed. Cation‐exchange data are also presented for representative Morley and Blount profiles.
Soil Water Measurement with Gamma Attenuation
Authors: Reginato R. J. , van Bavel C. H. M. 
Published: July 2010

AbstractGamma‐ray attenuation measurements of wet density were made with a 5‐mc. Cs137 source over a pathlength of about 30 cm. Data were obtained for glass‐and‐water systems as well as for soil materials of varying water content. The equipment was designed for use in the measurement of water content of soil in situ in 1‐cm. increments, without any collimation of the beam.Experimental results verify theoretical considerations on the use of gamma attenuation for soil water measurement. For equipment calibration, the unattenuated beam intensity and the attenuation coefficients for oven‐dry soil and water need be determined to make use of the exponential inverse square law for calculating the water content, given the dry density. The data demonstrate that the difference in the attenuation coefficients of dry soil and water must be taken into account.Accuracy of the method, for a total count of 20,000, is 0.010 g. cm.‐3 for water contents from 0.050 to 0.400 g. cm.‐3 at a dry density of 1.300 g. cm.‐3. For the same total count, a precision of 0.006 g. cm.‐3 is demonstrated.
X‐Ray Studies of Crystalline Swelling in Montmorillonites
Authors: Fink D. H. , Thomas G. W. 
Published: July 2010

AbstractSwelling properties of several montmorillonites (Li‐, Na‐, or Ca‐saturated) in water systems were studied using low‐angle X‐ray diffraction. All Li‐montmorillonites expanded linearly with water contents greater than 35%. Sodium‐hectorite also exhibited similar expansion. Sodium‐saturated Otay and Wyoming bentonites and nontronite, however, showed step‐wise expansion to about 110% water, and linear expansion at higher water contents. All calcium montmorillonites expanded in a step‐wise manner to a maximum spacing of about 20Å. The experimental techniques also were applied to the swelling properties of soil clays known to be high in montmorillonite. Results suggest that the poor crystallinity of soil montmorillonites is much more apparent at high water contents.
Fixation of Hydroxy‐Aluminum Polymers by Vermiculite
Authors: Hsu Pa Ho , Bates T. F. 
Published: July 2010

AbstractThe addition of vermiculite to hydroxy‐aluminum (OH‐Al) solutions prepared by the controlled addition of NaOH to AlCl3 results in the fixation of OH‐Al polymers by the clay. With solutions of NaOH/Al molar ratios = 0.3 to 2.1, the polymers held by the clay are of nearly constant composition, very close to the formula [Al6(OH)12]6+ (single ring) or [Al10(OH)22]8+ (double ring). The polymers are present in a single layer in the interlayer space. All specimens give a strong 14Å. X‐ray diffraction peak of similar intensity on K+ saturation even though the proportion of cation‐exchange positions occupied by the OH‐Al polymers varies from 24% to 61% on an equivalent basis.With solutions of NaOH/Al = 2.25 to 2.70, the polymers held by clay gradually increase in size and decrease in net positive charge per Al atom with increasing NaOH/Al ratio. The polymers are also present in a single layer in the interlayer space, but it takes more Al atoms and a longer time for the polymers in this group to produce a 14Å. peak of an intensity corresponding to that obtained when the Al is in the form of single or double ring units. In those specimens in which the amount of Al fixed is not sufficient to hold the vermiculite layer apart effectively, the Al polymer‐vermiculite layer is randomly interstratified with K‐vermiculite, and the resultant X‐ray diffraction patterns vary widely, some appearing as though X‐ray amorphous components were present.For all of the above mentioned specimens, no noticeable change has been found in the composition of the polymers held by clay minerals during aging up to 6 months. No crystalline Al(OH)3 was detected in any of these specimens. It is concluded that vermiculite functions as an anion which has a strong affinity for OH‐Al polymers and which inhibits the formation of gibbsite in soils.At NaOH/Al = 3, no OH‐Al polymer is found in the interlayer space but crystalline Al(OH)3 forms outside the clay lattice within two weeks.
Nitrosation of Soil Organic Matter: I. Nature of Gases Evolved During Nitrous Acid Treatment of Lignins and Humic Substances
Authors: Stevenson F. J. , Swaby R. J. 
Published: July 2010

AbstractManometric and infrared studies of the gaseous products formed by reacting HNO2 with humic and fulvic acids, lignins. lignin‐building units, and polyphenols showed the presence of N2, N2O, and CO2. In addition, methyl nitrite (CH3ONO) occurred in the gases obtained from lignins and certain phenolic derivatives. The CH3ONO originated through dismutation of phenolic ethers; the CO2 from decarboxylation of aromatic acids and cleavage of ring structures. Aromatic‐like substances interfere with the determination of free amino groups in soil organic matter by the Van Slyke nitrous acid method.
Soil Surface Patterns of some Semiarid Soils in Northern Utah, Southern Idaho, and Northeastern Nevada
Authors: Hugie V. K. , Passey H. B. 
Published: July 2010

AbstractSurface soil patterns were classified and studied on 70 semiarid to subhumid areas with relict native vegetation in Utah, Idaho, and Nevada. Three general classes of soil surface conditions were recognized — prominently patterned, weakly patterned, and unpatterned. Prominent and weak patterns were further classified into polygonal surface soil patterns with and without segregation of coarse particles.Surface patterns were found to occur only on bare surface soil between clumps of plants on well‐drained and moderately well‐drained silt loam, silty clay loam, and very fine sandy loam textured soils. Polygonal patterns with segregated coarse particles were observed only on moderately well‐drained planosolic, lithosolic, and solonetzic soils containing basalt pebbles. Surface soil patterns did not occur under vegetation, mulch, stones, or gravel.Cycles of alternate freezing and thawing of the surface soil followed by desiccation result in the formation of polygonal surface soil patterns with and without segregation of coarse particles.