bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variation of Soil Properties within Mapping Units of Soils with Contrasting Substrata in Northwestern Ohio
Authors: McCormack D. E. , Wilding L. P. 
Published: July 2010

AbstractVariation of soil properties within mapping units of Seward, Rimer, Wauseon, Rawson, Haskins, and Mermill soils in northwestern Ohio was statistically summarized. These series have sandy or loamy upper sola that overlie a fine‐textured substrata. Ten randomly selected profiles within each of 22 delineations of these soils were characterized by field study. Standard deviation, standard error of the mean, and coefficient of variation were computed for each of 48 selected properties. The most variable properties were depth to mottling, depth to fine‐textured discontinuity, horizon thickness, texture, and chroma of the B2t horizon, percent of mottles having chromas of two or less, and grade of structure. Hue, value, and pH of all horizons, texture of the IIB horizon, and size and shape of structure were the least variable. 54% of the profiles had IIB horizons in areas mapped as soils in which this horizon was lacking; 78% had IIB horizons in areas mapped as soils having this horizon. Little difference in other properties was noted between areas mapped as soils representing the two conditions. These soils were correctly classified with regard to soil series at 37% of the 220 observations. Careful study in such complex areas is essential before establishing a legend.
Physical Properties of Peats as Related to Degree of Decomposition
Authors: Boelter D. H. 
Published: July 2010

AbstractImportant physical characteristics, such as water retention, water yield coefficient, and hydraulic conductivity, vary greatly for representative northern Minnesota peat materials. The differences are related to the degree of decomposition, which largely determines the porosity and pore size distribution. Fiber content (> 0.1 mm) and bulk density are properties often measured to indicate the degree of decomposition of peat materials and are criteria used to distinguish fibric, hemic, and sapric peat types.Regression analyses showed a curvilinear relationship of water contents at saturation, 5 mbar, 0.1 bar, and 15 bar suctions, to fiber content (> 0.1 mm) and bulk density with coefficients of multiple determination (R2) ranging from .66 to .88. Regression analyses of the logarithm of hydraulic conductivity on fiber content (> 0.1 mm) and bulk density indicate a linear relationship (r2 = .54), although not as great due to the variability of hydraulic conductivity.Thus the classification of peat materials and organic soils based primarily on degree of decomposition as measured by fiber content and bulk density would relate significant information about their physical characteristics.
Primary and Secondary Origin of “Nonextractable” Soil Inorganic Phosphorus
Authors: Syers J. K. , Williams J. D. H. , Tyner E. H. , Walker T. W. 
Published: July 2010

Abstract“Nonextractable” soil inorganic phosphorus can have both a primary and a secondary origin. Apatite included within other minerals and phosphorus distributed throughout mineral lattices constitute the primary sources. “Nonextractable” secondary phosphorus accumulates during soil development and is associated with hydrated sesquioxides.
Relation between Staudinger Indices and Precipitabilities of Polysaccharides Extracted from Forest Soils
Authors: Saini G. R. , Salonius P. O. 
Published: July 2010

AbstractFractional precipitation of polysaccharides extracted with hot water from forest soils indicated that the organic layers contained a mixture of up to three polysaccharide fractions.The precipitabilities of the polysaccharide fractions ranged between 0.48 and 0.74 and the Staudinger indices had a range of 70 to 150. The precipitabilities and the Staudinger indices were inversely related in a linear fashion.
Radiocarbon Chronology of the Florida Everglades Peat
Authors: McDowell L. L. , Stephens J. C. , Stewart E. H. 
Published: July 2010

AbstractRadiocarbon measurements on two peat profiles near Belle Glade, Fla., indicate that peat formation in the Upper Everglades began during late Hypsithermal time, about 4,400 years B.P. (before present). Initially, peat development was very slow. About 500 to 1,000 years were required to build up the 7.6 cm of basal mucky peat, composed of a mixture of marl and organic matter. Then about 3,500 to 4,000 years ago, as a result of environmental changes, plant growths increased rapidly and were preserved as fibrous peats with very little mineral admixture. This rapid development of peat is contemporaneous with a rapid eustatic rise in sea level.Peat development proceeded rapidly (about 7.3 cm/century) from about 3,500 years to 1,200 years B.P. During this interim the existing peat, measuring about 1.37 m in thickness, was developed. By A. D. 1914 the peat had developed to a depth of about 3.65 m. This represents an average peat development of about 8.4 cm/century (4,400 B.P. to A.D. 1914).The Everglades Basin, prior to the initiation of drainage programs in the early 1900's, was inundated for a large part of the year. Since drainage, over a period of 50 years, about 1.8 m, or one‐half, of the original profile has been destroyed by the prevailing aerobic conditions.
Clay Translocation and Albic Tongue Formation in Two Glossoboralfs of West‐Central Wisconsin
Authors: Ranney Richard W. , Beatty Marvin T. 
Published: July 2010

AbstractSoil columns from two Typic Glossoboralfs were dissected to separate albic tongues and argillic B horizon material. Tongues and B horizon material have similar coarse/fine (50‐20µ/20‐2µ) silt ratios in the upper B horizon indicating that tongues could have been formed in place by eluviation of clay from certain zones of the B horizon.Lower in the B horizon the tongues consistently have different coarse/fine silt ratios than does adjacent B horizon material. Mineralogical analysis of silts gave no indication of differential weathering of quartz, alkali feldspars, or mica which together make up 85 to 90% of the fine silt (20‐2µ). The particle‐size distribution of silts in the lower albic tongues is taken to indicate that translocation of silts and sands has been involved in the formation of these tongues.Higher proportions of quartz, feldspars and mica in the coarse clay (2‐.2µ) of upper albic tongues indicate that montmorillonite, vermiculite, pedogenic chlorite and kaolinite have been preferentially removed. This, and the mineralogical similarity of fine clay (<0.2µ) between eluvial and illuvial zones, indicate that clay translocation in these soils is accomplished primarily by movement of clay particles in suspension without appreciable dissolution of crystal structures.Spodic horizons have begun to form in the albic horizons of some Glossoboralfs of the study area and Spodosols are common in coarser parent materials. Processes of illuviation inferred from this investigation, however are greatly different from those generally considered typical of Spodosols.
Profile Modification of a Slowly Permeable Soil
Authors: Eck H. V. , Taylor H. M. 
Published: July 2010

AbstractUnder limited water (preplant irrigation only), profile modification of Pullman silty clay loam to depths of 90 and 150 cm increased grain sorghum (Sorghum vulgare, Pers.) yields by 66.2 and 80.1%, respectively, over a 3‐year period. Modification (both 90 and 150 cm) increased water use efficiency in grain and total dry matter production by 41.3 and 25.2%, respectively. The increased yields and water use efficiencies resulted from changes in amount and distribution of stored water in the profile and from changes in plant rooting patterns.Under adequate irrigation, profile modification had little effect on grain or stover yields but increased water use efficiency in two of three seasons.
Chemical Properties of Allophane from Hawaiian and Japanese Soils
Authors: Lai Sung‐ho , Swindale L. D. 
Published: July 2010

AbstractFour moderately to strongly weathered soils from Hawaii and one moderately weathered soil from Japan, all derived from volcanic ash, were treated to separate out the allophane. The separates are described. With one exception, the fine clay fractions (<0.1µ) were almost X‐amorphous with only weak bands of 2:1 lattice clay minerals. The exception, the Waikaloa soil, contained much halloysite. Coarse‐clay fractions (2‐0.1µ) were mostly crystalline mica, kaolin and gibbsite. Differential thermograms of the amorphous fine clays were characteristic of allophane. The area of the low temperature endotherm correlated with the degree of crystallinity estimated from X‐ray data. Silica‐alumina molar ratios for the fine clays, varying from 0.927 to 1.50, were larger than the ratios for whole soils. The ratios for the three fine clays fractions which appeared least crystalline were all close to 1.0. Loss on ignition was inversely correlated with the silica‐alumina ratios. The allophane in these soils was fibrous and sponge‐like. The main infrared absorption band shifted from 9.70 to 10.29µ with increasing weight ratio of Al2O3/(Al2O3 + SiO2) and apparently reflected a change in state of coordination. Cation exchange capacities (CEC) of the separated fractions increased with increasing pH. There was a correlation between the apparent degree of crystallinity in X‐ray patterns of fine clays and the total change in CEC from pH 4 to pH 8.5. The CEC and infrared data together suggested that some stabilized AlIV‐O‐AlIV bonds occur in the allophane minerals.
Sodium‐Calcium Exchange Behavior in Organic Soils
Authors: Naylor D. V. , Overstreet Roy 
Published: July 2010

AbstractThe exchange complex of two organic soils from the Sacramento‐San Joaquin delta of California was easily saturated with calcium. However, the Ca2+ of the calcium‐saturated soil was difficult to replace with Na+ even when the calcium‐saturated soils were leached with 1N NaCl. Exchange of the Ca2+ by Na+ was found to be reasonably stoichiometric and complete after extensive leaching of the calcium‐saturated soils with the 1N NaCl solution. A large fraction of the adsorbed Ca2+ was extremely difficult to replace with Na+ when the soils were leached with large volumes of 0.01N NaCl.The Ca‐Na ion‐exchange isotherms of the soils were determined through the use of Vanselow's and Gapon's ion‐exchange equations. Vanselow's ion‐exchange “constant” indicated an increased selectivity for Ca2+ over Na+ as the amount of exchangeable Na+ increased while Gapon's equation yielded a constant selectivity throughout the isotherms. Both equations suggested that the soils exhibit a very large selectivity for Ca2+ over Na+, especially as the amount of exchangeable sodium becomes appreciable.
Ionic Interaction in Diffusion
Authors: Frere M. H. 
Published: July 2010

AbstractAnalysis of the system of a plant root taking up ions at a constant rate shows that the apparent diffusion coefficient of each ion can change with time, distance from the root, composition of the solution, and the rates of uptake of all the ions. A numerical method, developed to include the electrical interaction of ions during diffusion, was used to simulate the concentration behavior in a sand culture. It is concluded that the assumption of constant diffusion coefficients in models of soil‐plant system can only be a first approximation.
Effect of Soil Potassium, Potassium Fertilizer, and Method of Placement Upon Lodging in Corn (Zea mays L.)
Authors: Walker W. M. , Parks W. L. 
Published: July 2010

AbstractA quadratic regression equation including selected linear interactions was fitted to lodging percentages of corn grown on a Hartsells loam with varying K soil test levels and K fertilizer rates applied in the row and broadcast. The study was conducted over a 3‐year period and main effect variables for year, soil test K, and fertilizer K, as well as selected linear interactions, were included in a regression analysis. Both soil and fertilizer K significantly decreased percent lodging, and there was a significant difference in lodging among years. The significant soil K and fertilizer K interaction indicated that the effect of fertilizer K upon lodging varied with soil‐test level. There was also a significant interaction of fertilizer K with year indicating that the effect of K upon lodging varied among years.
Cotton Growth in an Acid Fragipan Subsoil: II. Effects of Soluble Calcium, Magnesium, and Aluminum on Roots and Tops
Authors: Soileau J. M. , Engelstad O. P. , Martin J. B. 
Published: July 2010

AbstractGreenhouse and laboratory studies were made to evaluate the effects of soluble Ca, Mg, and Al on cotton (Gossypium hirsutum) growth in highly acid fragipan subsoil (Dickson series). Growth response was not related to soil pH, per se. The high level of soluble Al inherent in the Dickson subsoil greatly inhibited cotton growth by inducing morphological damage to the root system and by depressing uptake of Ca. Yield reductions were accompanied by Al concentrations above 0.2 and 0.02% in roots and tops, respectively. Severe Ca deficiency symptoms in tops and roots were observed where Ca was maintained at inherent subsoil levels and Al was either neutralized with base or was leached from the soil system. Although all treatment yields were not related to Ca or Mg concentrations in plant tissue, results suggested that the native levels of exchangeable Ca and Mg in Dickson fragipan subsoil may be limiting for cotton growth. Whether or not the “inherent” deficiency of Ca is entirely or only partly Al‐induced was not conclusively determined; however, this question may be relatively unimportant in view of the other harmful effects of high levels of soluble Al on cotton growth.
Effect and Interaction of Molybdenum and Limestone on Growth and Molybdenum Content of Cauliflower, Alfalfa, and Bromegrass on Acid Soils
Authors: Gupta Umesh C. 
Published: July 2010

AbstractA greenhouse study involving four levels each of Mo and limestone indicated that without application of both Mo and lime, the cauliflower (Brassica oleracea, var. botrytis L.) crop produced very poor yields on the three soils investigated. Alfalfa (Medicago sativa L., var. ‘Narragansett’) was also a failure without added lime. At soil pH values of 5.5 and above, Mo applications increased the yield of alfalfa on Culloden sandy loam and O'Leary sandy clay loam soils, but gave no response on Acadia silty clay loam soil. Bromegrass (Bromus inermis Leyss., var. ‘Saratoga’) showed a marked response to application of lime, but very little response to application of Mo. Cauliflower yield showed a highly significant Mo × lime interaction on Culloden and O'Leary soils, where without added Mo, lime treatment up to pH 6.5 failed to show any increase in yield. Addition of different levels of lime did not change the exchangeable Mo content of any of the three soils, after growing crops.The application of Mo or lime increased the Mo content of all crop tissues up to the highest level of applied Mo or lime. Application of lime substantially increased the Mo content of cauliflower and alfalfa while bromegrass showed less increase. There was a marked Mo × lime interaction on the Mo content of all crops, with much higher Mo contents in the plant when lime and Mo were applied together than when either treatment was applied alone. Liming to pH 6.5 without added Mo did not increase the Mo content of crops over 1.5 ppm.In the absence of added Mo, cupping and drying of the edges of true leaves of cauliflower appeared at the early stage of growth whether or not lime had been applied to the soils. During the later stages of growth, these symptoms in most cases were associated with yellowing between the veins of leaves.
Inverse Formulation and Finite Difference Solution to Partially Saturated Seepage from Canals
Authors: Jeppson Roland W. , Nelson R. William 
Published: July 2010

AbstractThe mathematical model describing Darcian flow of water through soils approximates actual occurrences more closely when it permits regions of the flow to be partially saturated. A generally accepted relationship between effective permeability and capillary pressure is utilized to formulate and solve by inverse methods with finite differences the steady‐state flow system of water through soils. The inverse formulation considers the cartesian coordinates x and y as the dependent variables and the potential function ϕ and the two dimensional stream function ϕ as the independent variables (i.e. the problem is solved for x and y in the ϕψ plane). The approach is applied to the problem of seepage from a canal to a water table and a computer program (FORTRAN IV) has been written for solving this problem.
Cation Exchange Capacity and Weathering of Muscovite Macroflakes
Authors: Mokma D. L. , Syers J. K. , Jackson M. L. 
Published: July 2010

AbstractThe cation exchange capacity (CEC) of large (3‐ to 7‐cm2) muscovite macroflakes, determined with 45Ca, was 8.6 × 10‐7 meq/cm2 of geometrical surface, a value greater than the theoretical one of 3.5 × 10‐7 meq/cm2 calculated from the structural formula. The greater than theoretical CEC was attributed to exchange in areas of growth planes made accessible to the solution by (hkO) cleavage and by charged particle tracks. Similar values were obtained for BaEC (9.7 × 10‐7 meq/cm2) and CsEC (8.7 × 10‐7 meq/cm2). The excess of BaCl2, CsCl, or NaCl was not completely removed, whereas excess CaCl2 was removed, by five 100% methanol washings, as indicated by radiochemical measurements. The presence of excess BaCl2 and absence of CaCl2 were confirmed by electron micrographs of platinum‐carbon replicas of the muscovite cleavage surfaces, the former being removed by subsequent water washings. Hydrolysis of exchangeable Na was appreciable during water washings in the NaEC determinations, resulting in a considerably lower measured NaEC (1.1 × 10‐7 meq/cm2), but little hydrolysis of exchangeable Ba or Cs occurred in water washings. Electron micrographs showed that the muscovite (001) cleavage surfaces had been etched during extensive salt treatments and that a weathering product had formed on the surfaces. The latter material was insoluble in water, but was removed by treatment with Na citrate‐NaHCO3, indicating a sesquioxidic composition. The CEC of muscovite flakes was unaffected by the etching and the sesquioxidic weathering product.
Comparisons of Measured and Theoretical Mn2+ Concentrations in Soil Suspensions
Authors: Bohn H. L. 
Published: July 2010

AbstractThe Mn2+ concentrations in control and autoclaved suspensions of nine acid and alkaline soils in 0.01M CaCl2 differed widely from the Mn2+ concentrations calculated from models which either require measurement of Eh or assume Eh to be fixed by another redox couple. An alternative model is proposed which expresses the equilibrium solubility of the manganese compounds in terms of pH — ½pMn. The values of pH — ½pMn measured in the suspensions of all the soils tested correspond to the solubility of MnO2.
Evaluation of Slow‐Release Nitrogen Sources on Merion Kentucky Bluegrass
Authors: Moberg E. L. , Waddington D. V. , Duich J. M. 
Published: July 2010

AbstractVarious slow‐release nitrogen sources were used to fertilize ‘Merion’ Kentucky bluegrass (Poa pratensis L.) for two growing seasons. Slow‐release sources were ureaform, activated sewage sludge, ADM (a coated urea), Urex (a urea‐paraffin product), and IBDU (isobutylidene diurea). Response to fertilization was measured by weekly determinations of clipping yield and color rating. Urex performed similarly to ADM, and response following application was quicker and greater than that from ureaform, sewage sludge, and IBDU. IBDU showed good controlled release characteristics, but initial response after fertilization was slow. Residual effects of IBDU gave green color earlier in the spring than other treatments. Nitrogen recovery in the clippings was determined. Recovery ranged from 54% for ADM to 22% for ureaform over the 2‐year period. Recovery from sewage sludge was 27%. The highest recoveries for IBDU and Urex treated plots were 46% and 52%, respectively. Recovery from a urea treatment was 52%.
Thermal Conductivity and Diffusivity of Soil Using a Cylindrical Heat Source
Authors: Moench A. F. , Evans D. D. 
Published: July 2010

AbstractThe interference of moisture migration upon measurements of the thermal constants in soil has been reduced by using a large‐diameter, cylindrical thermal probe which is heated at a constant rate. Using the initial portion of the experimental record (temperature versus time) and by taking account of the thermal contact resistance between the heat source and sample material, it is possible to obtain values of thermal conductivity accurate to within 4%. Real thermal conductivity is obtained by subtracting from the measured value the small effect of distillation which is estimated with the help of the theory of vapor diffusion in porous media. Results obtained for a sandy loam soil show that real thermal conductivity increases rapidly with water content from 6.05 × 10‐4 cal/cm per °C per sec., when air dry, to 26.0 × 10‐4 cal/°C per cm per sec. at 30% of saturation. Thereafter it increases less rapidly (in proportion to the increase of volumetric heat capacity) to a value of 59.5 × 10‐4 cal/°C per cm per sec. at complete saturation. Real thermal diffusivity remains essentially constant at water contents above 30% of saturation. The method can also be used for rapid and accurate measurement of the thermal conductivity of liquids provided their volumetric heat capacities are known.
Thermodynamics of Copper(II)—Calcium Exchange on Bentonite Clay
Authors: El‐Sayed M. H. , Burau R. G. , Babcock K. L. 
Published: July 2010

AbstractThermodynamic parameters were derived for the exchange reaction between Cu(II) and calcium on bentonite clay in systems essentially devoid of precipitation, hydroxylation, and complex formation. Although the exchange isotherms showed preference of clay for calcium this proved to be only apparent since a large component of the standard free energy change for copper adsorption was due to entropy loss. The stronger binding of copper ions to clay surfaces was revealed, however, by the standard enthalpy changes and their arrangement in a more orderly structure than calcium ions on the surface was inferred from the magnitude of standard entropy changes. The activity coefficients of the adsorbed ions were obtained and were used to test the assumptions inherent in the treatment and the significance of their variations with clay composition was discussed.
Nutrient Cation Flows in Soil Around Plant Roots
Authors: Brewster J. L. , Tinker P. B. 
Published: July 2010

AbstractThe aim of the work was to test the relative importance of mass flow and diffusion in supplying nutrients to plant roots at different stages of growth, and whether there were, on average, important depletions or accumulations around the roots. Leeks (Allium porrum var. ‘Musselburgh’) were grown in large covered pots set in the field, and transpiration was measured by weighing. Nutrient content and root length were measured at four harvests, and soil solution composition was measured on 12 occasions. From this the mean inflows (uptake in moles/cm of root/sec) were calculated for K, Ca, Mg, and Na in three growth periods. They decreased strongly for sodium, slightly for potassium and magnesium, and remained constant for calcium.The ‘apparent mass flow’ was taken as water inflow (ml/cm per sec) times soil solution concentration. It was small compared to total inflow for potassium, but increased with time; it was much larger than inflow for calcium, and slightly larger for magnesium and sodium.The Passioura equation was used to calculate mean solution concentrations at the root surface. This indicated that the potassium concentration decreased to between 1/7 and ½ of the original, but that of Ca, Mg, and Na was slightly increased on average. Root demand coefficients ᾱr̄, are calculated from the results.