bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil‐Geomorphic Relationships in a First‐Order Valley in Central New York
Authors: Hanna W. E. , Daugherty L. A. , Arnold R. W. 
Published: July 2010

AbstractMorphologically the soils in Hemlock Creek watershed are related to geomorphic development since glaciation. Initial drift deposits covering the 75‐ha area in south‐central New York were modified by mass movement (solifluction) and then altered by fluvial aggradation‐degradation under a periglacial environment, and by erosion in more recent times. Eight soil profiles representative of the geomorphic components forming the watershed were evaluated.Fragiochrepts dominate the shoulder, backslope, and upper footslope components. They are also the major soils on congeliturbate terraces and on step‐treads of the upper basin. Fragiaquepts are common on the lower footslope and toeslope components and also occur on portions of the step‐treads of the cirque‐like basin. Fragipans have formed in both glacial till and congeliturbate deposits indicating a pedologic origin. Structural expression and density of the pans increase with a decrease in natural drainage in both deposits. Dystrochrepts are dominant soils on the summit and on the intermediate level fluvial terraces; Entisols occur on the low level alluvial terraces. Pan formation is thought to be precluded by nearness of bedrock (< 1 m) to the surface in the summit area and by matrix textures in the fluvial terraces. Stratigraphic changes that produce distinct discontinuities in fluvial terrace profiles are readily evident. Incipient stratification in congeliturbate deposits appears to affect soil morphology, especially horizon thickness, in these relatively young soils.
Design and Use of Closed‐top Infiltrometers
Authors: Dixon R. M. 
Published: July 2010

AbstractSeveral similar closed‐top infiltrometers were designed and used to simulate effective surface heads ranging from −3 to +1 cm of water. Design was based on the principle that natural positive soil air pressure may be simulated by creating an equivalent negative air pressure above ponded surface water. Effective surface head hs, defined as the difference between the ponded water depth hw and either the actual or simulated soil air pressure head ha, is negative when ha is greater than hw. Under natural field conditions, negative hs often causes counterflow of soil air during water infiltration. Narrow ranges in hs surrounding zero greatly affect infiltration by controlling air and water flow in soil macropores and weakly hydrophilic micropores. Thirty‐minute cumulative infiltration increased 19% per centimeter increase in hs for one soil and 33% per centimeter for another soil.Closed‐top infiltrometers make possible realistic infiltration measurements under the negative hs commonly produced by rain and irrigation waters as they infiltrate natural soils. These devices may also be useful in studying the infiltration effects of several interacting parameters that are related to hs including soil surface macroporosity and roughness, macropore space extent and continuity, antecedent soil air and water, surface wettability and water repellency, wetted surface area and shape, and surface crust and slope.The infiltration response to hs in the range −3 to +1 cm is of practical significance since such a range results from common soil and water management practices.
Soybean and Corn Rooting in Southwestern Minnesota: II. Root Distributions and Related Water Inflow
Authors: Allmaras R. R. , Nelson W. W. , Voorhees W. B. 
Published: July 2010

AbstractRoot length density (RLD) of corn (Zea mays L.) and two isolines (determinate and indeterminate) of Harosoy soybean (Glycine max. L. Merr.) in a Nicollet soil were measured from 1 July to 15 Aug. 1971. These measurements, along with water uptake sinks in these vertically developing root systems, were used to evaluate water relations of these three crops.Both soybean isolines had about 0.2 cm/cm3 RLD in the Ap layer with values < 0.1 below the Ap layer. This RLD distribution persisted with depth as the root system expanded vertically. Corn RLD were about 0.3 initially in the Ap layer, and as the root system expanded vertically, maximum RLD of about 0.3 was produced even to the 100‐cm depth on 9 Aug. Vertical extension rates of corn after 1 July were 1.3 cm/day as compared with 1.7 for soybeans, but maximum rooting depths on 9 Aug. were 145 and 120 cm, respectively.Modal specific water inflows were 0.03 cm3/cm root per day—maximal values for soybeans were 0.2; maximal values for corn were about 0.05. Maximum soybean rooting depths coincided with maximum depth of water uptake sink, but corn rooting depths ranged 15 to 30 cm deeper than the water uptake sink.Specific water inflow generally increased as soil hydraulic conductivity increased and RLD decreased, which agrees with models for steady‐state water flow into single roots. At low RLD, specific water inflows were either constant or increased as hydraulic conductivity decreased. This increased root resistance to water flow at the lower fringes of rooting may have resulted from low soil temperatures. Soybean root conductivities decreased with decreasing soil water potential. Corn root conductivities were largest at about −700 mbars and decreased as soil water potential decreased. Decreases of corn root conductivity resulted from potentials > −700 mbars when soil temperatures were low.
Linear Dispersion in Finite Columns
Authors: Parlange J.‐Y. , Starr J. L. 
Published: July 2010

AbstractThe effect of the finite length of a soil column on the miscible displacement of a solute is analyzed. The boundary conditions at both ends of the column affect the breakthrough curve, while only the boundary condition at the entrance of the column affects the profile within the column to any extent. The interaction between boundary conditions and column length is such that while the breakthrough curve is essentially that given by the standard solution for a semi‐infinite column, even for relatively short columns, the concentration profile is greatly affected by the finite length of the soil column.
Redox Potential in Irrigated Desert Soils as an Indicator of Aeration Status
Authors: Meek B. D. , Grass L. B. 
Published: July 2010

AbstractThe redox potential (Eh) of irrigated desert soils was evaluated under a wide range of conditions. Factors important in controlling Eh were temperature, flooding time, soil water content, and energy source. Field heterogeneity necessitated using 10 to 20 electrodes (placed in a 30‐cm square) to characterize a treatment. The Eh varied over a short distance with variations not due to poisoning or erratic electrode readings.A 5C increase in temperature at the 15‐cm depth resulted in a 50‐mV decrease in redox potential. The length of soil saturation time correlated directly with the decrease in Eh. When the soil was not saturated during irrigation (sprinkler or drip), Eh decreased less than when the soil was flooded. The amount of energy available to microorganisms has a major effect on how low the Eh decreased in a flooded soil.
Boron Toxicity in Red Pine Following Municipal Waste Water Irrigation
Authors: Neary Daniel G. , Schneider G. , White D. P. 
Published: July 2010

AbstractFoliar boron toxicity symptoms, a needle tip necrosis and discoloration, appeared in a 20‐year‐old red pine plantation (Pinus resinosa Ait) after two growing seasons (a total of 34 weeks) of spray irrigation with municipal waste water. Irrigation rates of 25, 50, and 88 mm/week produced significant increases in the boron contents of current foliage, forest humus, and mineral soil. Foliage, humus and upper 15 cm of mineral soil of the unirrigated plots contained 22 ppm, 16 ppm, and 1 kg/ha of boron, respectively. The high irrigation rate increased boron levels to 75 ppm, 90 ppm, and 4 kg/ha, respectively. Despite low boron concentrations (1 ppm) in the waste water, total boron loadings were equivalent to applications of 67.3, 135.7, and 230.1 kg/ha of borax fertilizer (11.3% B).
Tests of the Concept of Secondary Frost Heaving
Authors: Loch J. P. G. , Miller R. D. 
Published: July 2010

AbstractHeaving tests were conducted with 2–4, 4–8, and 8–16 µm soil fractions in special apparatus in which sliding friction (during heaving) was eliminated by confining the specimen as in standard triaxial test apparatus. Maximum pressures developed by heaving exceeded those computed by a primary heaving model (using air intrusion data) by factors as large as 3 to 6. Maximum pressures and rates of heave at constant pressures depended on temperature gradient and were maximal at gradients between 1 and 3C cm‐1.Comparisons with simplified transport equations for a frozen fringe adjacent to a growing ice lens (the characteristic feature of secondary heaving) indicate that pore ice in the frozen fringe contributes to water transport for lens growth but this may be offset by plastic counter‐flow of ice at large temperature gradients, accounting for the gradient‐dependent maxima.Results were interpreted as supporting the concept of secondary heaving.
Infrared Study of Exchangeable Cation Hydration in Montmorillonite
Authors: Sposito Garrison , Anderson Duwayne M. 
Published: July 2010

AbstractInfrared absorption spectra in the 3000 cm‐1 and 1600 cm‐1 regions are reported for thin films of Na‐, K‐, Li‐, and Ca‐Wyoming bentonite previously dehydrated over P2O5 and over LiCl · H2O at room temperature. The spectra of Na‐ and K‐clay exhibited very similar features in the 3000–3500 cm‐1 region, which, together with other data, lead to the proposal that the exchangeable cations on these montmorillonites are dehydrated at relative humidities less than about 11%. The spectra of Li‐ and Ca‐clay are very different from those of Na‐ and K‐clay. A sharp doublet structure appears to be centered near 3650 cm‐1 and the absorption in the 3000–3500cm‐1 region generally is much deeper and broader. These differences are interpreted as evidence of the hydration of the exchangeable cations Li+ and Ca2+ at relative humidities less than about 11%. The conclusions drawn here are in agreement with previous findings based on infrared, differential thermal analysis, and desorption isotherm studies.
Effect of Lime on Boron Transport to and Uptake by Cotton
Authors: Scott H. D. , Beasley S. D. , Thompson L. F. 
Published: July 2010

AbstractDeficiencies of Boron have occurred in cotton (Gossypium hirsutum L.) grown in coarse textured soils during periods of moisture stress and in those soils which have been recently limed. These B deficiencies have generally been attributed to a decrease in soil B availability to cotton. As a result a greenhouse experiment was conducted to study (i) the amounts of adsorption and diffusivity rates of B in two silt loams and (ii) B absorption by cotton grown in pots.Addition of lime increased B adsorption by both a Taloka silt loam and a Calloway silt loam. Maximum B adsorption occurred on the seventh day after its addition but did not differ appreciably from the one day equilibration time. The adsorption data could not be accurately described by the Langmuir adsorption equation.Increasing amounts of lime and decreasing soil water content caused a decrease in B diffusivity in the two soils. Diffusivity values when averaged over all treatments were 4.6 × 10‐6 and 2.7 × 10‐6 cm2/sec for the Calloway and Taloka soils, respectively.The addition of lime to the Taloka soil reduced the growth and rate of development of cotton grown in greenhouse pots. Plant parameters such as date of emergence, plant height, dry weight accumulation, total B content, root length and root surface were reduced by the lime addition. The rate of B absorption by cotton decreased until square initiation then increased. This result suggests that cotton has differing B requirements during the growing season and that these requirements are highest during the early growth stages and fruit formation. Even though the total amount was lower, the rate of absorption of B by those plants growing in the limed soil was greater than those growing in the soil which received no addition of lime. This was attributed to the lime having a greater effect in reducing the magnitude of root surface area as compared to its effect in reducing the rate of B transport within the soil.
Effect of Surface Applied Sulfuric Acid on Water Penetration into Dry Calcareous and Sodic Soils
Authors: Yahia T. A. , Miyamoto S. , Stroehlein J. L. 
Published: July 2010

AbstractSulfuric acid, a surplus by‐product of copper smelters in the Southwest, was studied to determine a possible role in reclamation and revegetation of calcareous and sodic range soils. The rate of water penetration into dry calcareous soils was measured in columns as well as boxes after concentrated (93%) sulfuric acid was applied to the soil surfaces. The rate of penetration increased with increasing acid application rates, but then decreased, with optimum application rates ranging from 5 to 15 metric tons/ha. Acid was especially effective in increasing the rate of penetration into sodium‐affected calcareous soils. When acid was applied as a band on the soil surface, the wetting front advanced in an elongated semicircular form with depth. Surface applied acid was more effective than surface applied gypsum in increasing water penetration into sodiumsaturated soils. Sulfuric acid may be useful for increasing water penetration into and subsequently aiding in revegetation of sodium‐affected soils of semi‐arid regions.
Quartz Oxygen Isotopic Stability in Relation to Isolation from Sediments and Diversity of Source
Authors: Sridhar K. , Jackson M. L. , Clayton R. N. 
Published: July 2010

AbstractThe NaOH boiling treatment to remove amorphous silica relics in the quartz isolation procedure is unnecessary because the subsequent H2SiF6 treatment dissolves both the amorphous silica relics and feldspars. Washing with 0.1N HF, water, and saturated boric acid in the new procedure removed fluorates that precipitate during the H2SiF6 treatment. Failure to remove the fluorates depressed the oxygen yield (to as much as 85%) of theoretical SiO2 and slightly raised the quartz weight percent, but the oxygen isotopic ratio of quartz derived from various sources was not affected by these washings, by Na2S2O7 fusion, or by H2SiF6 treatment.When 35 to 45% of the outer shells of the 1–3.5, 3.5–7, and 7–10 µm quartz size fractions from Cretaceous (Pierre) marine shales was dissolved with 3N HF, the quartz δ18O decreased by 0.8, 2.1, and 2.6 o/oo for a central‐basin shale and 0.7, 1.2, and 0.8 o/oo for a near‐shore shale, respectively. The trend, the greater the particle size the greater the δ18O decrease, is the opposite of that expected (finer particles, higher specific surface) if the δ18O decrease by HF treatment is a result of dissolving an isotopically exchanged portion and/or overgrowths in outer shells. The decrease appeared by scanning electron microscopy (SEM) to result from preferential dissolution of the cements holding fine quartz crystals (formed at low temperature) together as silt‐size clusters. A systematic increase in δ18O with decreasing grain size occurred in the quartz from the near‐shore shale (> 10 µm quartz, 16.1 o/oo; < 1 µm quartz, 21.8 o/oo). The increase was 6.7 o/oo from the central‐basin shale (> 10 µm quartz, 18.8 o/oo; < 1 µm quartz, 25.5 o/oo). The wide variation appears, from quartz particle morphology (SEM) and the response to partial dissolution, to result mainly from a mixing within each size fraction of different proportions of individually homogeneous quartz grains formed at various temperatures. Because of quartz oxygen isotopic stability, the isotopic ratio can be reliably used to trace source or provenance of fluvial and eolian sediments and soil parent materials.
The Slow Reaction which Continues After Phosphate Adsorption: Kinetics and Equilibrium in Some Tropical Soils
Authors: Munns D. N. , Fox R. L. 
Published: July 2010

AbstractDissolved phosphate was mixed with topsoil samples, and the decline in solution phosphate concentration (P) was followed for 200–300 days by periodically shaking and extracting subsamples with 1 or 10 mM CaCl2 (1:10).During the first 20–40 days, (P) declined faster in soil suspensions that were being shaken than it did in undisturbed soil at 0.1 bar moisture. After 40 days of reaction, shaking time had little effect.The slow fixation had first‐order kinetics with respect to (P). The relative rate was faster in an Andept than in three Oxisols. It was unaffected by lime, though lime increased the strength of adsorption.Equilibrium was achieved at 50 days in an Andept and 100–200 days in three Oxisols. At equilibrium, the amount of adsorbed phosphate remaining labile was estimated from values of (P), using 6‐day adsorption isotherms. Labile phosphate so estimated amounted to 30–50% of the added phosphate, implying that the residual value of phosphate added to these soils should be substantial and permanent except for removal by crops and erosion.Desorption isotherms diverged from adsorption isotherms less markedly with increasing time after phosphate addition, as if the slow reaction caused much of the apparent hysteresis.
Adsorption of Selenite and Phosphate on an Allophane Clay
Authors: Rājan S. S. S. , Watkinson J. H. 
Published: July 2010

AbstractSelenite was adsorbed on an allophane clay from solutions of different concentrations at pH 5.0, at 30C, and under a N2 atmosphere, and the amounts of sulfate, silicate and hydroxyl ions released were measured. The results were compared with those from a similar study with phosphate on the same clay.The results indicate that at low concentrations both phosphate and selenite exchanged with adsorbed sulfate, adsorbed silicate, and aquo and hydroxo groups. About three times more phosphate than selenite was adsorbed, due mainly to phosphate displacing more aquo groups and thus making the surface less positive.At high concentrations, whereas the selenite adsorption reached a maximum, phosphate continued to be adsorbed. The latter was due to phosphate displacing structural silicate and probably also to disruption of hydrous oxide polymers. A two‐term Langmuir equation distinguished adsorption by surface ligand exchange from these other reactions at high concentration.A selenite desorption experiment showed that phosphate displaced all of the selenite adsorbed. Phosphate was adsorbed with greater strength, the selectivity coefficient, KSeP, being 2.2.
Defining Ranges of Soil Characteristics
Authors: Jansen I. J. , Arnold R. W. 
Published: July 2010

AbstractA method is developed for using quantitative sample data to characterize mappable bodies of soil. Inclusions are separated into two kinds. The first consists of included bodies of soil that are recognized as separate entities, but not mappable because of scale limitations. The second consists of scattered areas having extreme expression of some significant property but not recognized as separate geographic entities.Inclusions of the first kind are sampled separately and treated as separate entities. The location and setting of these inclusions can be described in relation to the dominant soil body. A range of expression for each measurable soil property of interest is determined separately for each soil entity. The ranges are derived from the sample data and are designed to include a fixed portion of the total population of values rather than to be all inclusive. Soil areas having extreme expression of some particular property (falling outside of the defined range) are inclusions of the second kind. The location and setting of those soil areas cannot be readily described but their extent is controlled.The tolerance interval procedure is used to calculate range limits from sample data when a normal distribution can be assumed. The resulting range can be said to include a predetermined portion of the total population of values with a specified degree of confidence. When the distribution is believed to deviate markedly from normal, the range limits are set subjectively by observing a frequency distribution of the sample data. Ranges set by the tolerance interval procedure were generally somewhat wider than those set subjectively, because the tolerance interval procedure allows for the imperfect relationship between the sample and the population and enables one to make confidence statements about the ranges defined.
An Evaluation of Sulfur‐coated Urea as a Preplant Total Season Nitrogen Supply for Trellised Tomatoes
Authors: Shelton J. E. 
Published: July 2010

AbstractThe use of a controlled release N source for the production of trellised tomatoes (Lycopersicon esculentum) which require frequent topdressings would be desirable. Three sulfur‐coated urea (SCU) materials having release rates of 11.4, 21.5, and 29.3% over a 7‐day period were compared to NH4NO3 applied preplant or as multiple applications. Nitrogen rates were 392, 560, and 729 kg N/ha. Marketable yields from an application of SCU11.4 at 392 or 560 kg N/ha were greater than with the same rate of N as NH4NO3 either as preplant or split applications. When SCU21.5 or SCU29.3 was used, the yields were comparable to a single application of NH4NO3. Differences in fruit number per plot were not significantly related to treatments. However, there was a significant difference in average fruit weight which was correlated with total yield. Tissue N content was highest at the first sampling from a single application of NH4NO3 and lowest from SCU11.4. However, at later sampling periods the N content was maintained at a higher level with SCU11.4. Although 729 kg N/ha as a single application of NH4NO3 detrimentally affected plant growth and production, this effect was not noted with the sulfur‐coated urea materials.
The Release of Nitrogen from Sulfur‐coated Urea as Affected by Soil Moisture, Coating Weight, and Method of Placement
Authors: Prasad M. 
Published: July 2010

AbstractInformation on the release of N from sulfur‐coated urea (SCU) as affected by soil moisture in the aerated range is lacking. Laboratory incubation experiments were therefore conducted on two soils to study the release of N from SCU as affected by soil moisture in the aerated range, coating weight (SCU‐28 and SCU‐9), and method of placement (on one soil only).In the calcareous Princes Town soil the release of N from SCU increased with increasing moisture throughout the 9 weeks of study. In acid Talparo soil similar trends were present up to 3 weeks, but at 6 and 9 weeks maximum release of N occurred at medium moisture (soil moisture at pF 2.4) and minimum release at low moisture (soil moisture at pF 3.5).In Princes Town soil the difference in release of N from SCU‐28 and SCU‐9 remained throughout the 9 weeks. By 9 weeks SCU‐9 (heavy coat) released more N at high moisture level (soil moisture at pF 1.0) than SCU‐28 (light coat) at low moisture. In Talparo soil the effect of coating weight on the release of N at three moisture levels was considerably reduced from 6 weeks onwards.Ammonia volatilization losses were recorded only with Princes Town soil but they never exceeded 2.5% of the total N applied. The release of N from SCU was faster when the granules were mixed with the soil rather than surface applied. This difference between surface and mixed application was greater at high soil moisture levels.
Determination of 14C‐Labeled Pesticides in Soils by a Dry Combustion Technique
Authors: Cheng H. H. , Farrow F. O. 
Published: July 2010

AbstractA dry combustion method for oxidation of 14C‐labeled pesticides in soils and determination of total 14C is described. The method is a modification of the procedure using a Leco high‐temperature induction furnace for oxidation and determination of total C in soils. In the modified system, the CO2 evolved from sample oxidation is trapped in a NaOH solution, which can be analyzed for total 14C radioassay and for total C by titrimetry.