bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clay Mineral Genesis of Some New York Spodosols
Authors: Coen Gerald M. , Arnold Richard W. 
Published: July 2010

AbstractSome Spodosols in northern New York previously shown to have well crystallized montmorillonite in the albic horizon but only amorphous clay sized material in the spodic horizon were studied to determine the source or genesis of the montmorillonite. The soils used to test several hypotheses of the clay mineral genesis represented Orthods, Humods, and Aquods. These soils were also shown to be deficient in mica and chlorite in the sand, silt, and clay fractions. This allowed a test of the hypothesis that montmorillonite in albic horizons weathers from mica, a process which previously has been reported to be active. The presence of only traces of mica and chlorite in the sand and silt fractions would indicate that weathering of sand and silt sized minerals directly to clay sized minerals should not be important. However, the small amount (generally less than 3%) of clay sized materials in the pedons makes this assumption inconclusive.Soil solution studies, coupled with equilibrium diagrams, provide evidence that clay mineral synthesis from ions does not occur in these soils.The well crystallized clay sized minerals detected in the upper solum of the pedons studied may have (i) weathered directly from sand and silt sized minerals, (ii) been added as dust, or (iii) weathered from minerals added as dust. There is recent evidence that appreciable amounts of montmorillonite, illite, vermiculite, and kaolinite are deposited as dust throughout the northern United States. If projected figures are valid, dust could account for most of the montmorillonite in the albic horizons studied. Concomitant additions of chlorite and mica are not detected. Chlorite and mica added as dust, as well as any traces of these minerals present as sand or silt, must be weathered to some other species in the clay fraction, because they are not detected in the clays.It is proposed that in the Spodosols studied (i) any chlorite in the albic horizon is weathered to amorphous aluminosilicates and translocated to the spodic horizon, and (ii) mica is weathered to montmorillonite in the albic horizon, to vermiculite in the Bh horizon, and to “chloritized” vermiculite in the Bir horizon.
Forest Site Productivity Among Soil Taxonomic Units in Northern Lower Michigan
Authors: Shetron Stephen G. 
Published: July 2010

AbstractGrowth measurements (site index and cubic meter volume) and soil descriptions for 195 field plots on 12 soil taxa were obtained to evaluate the variation in tree growth of jack pine (Pinus banksiana L.), northern red oak (Quercus rubra L.), sugar maple (Acer saccharum Marsh.), and bigtooth aspen (Populas grandidentata Michx.) in northern lower Michigan.Jack pine had significant differences in growth among five of eight soil taxa. Red oak showed significant differences among four soil taxa. Sugar maple showed no significant differences in growth among five soil taxa. Bigtooth aspen exhibited significant differences in growth among four of eight soil taxa.Soil properties recorded for soil profile descriptions were related to the range in site index of each study species. Regression equations were developed for depth to mottling, depth to loamy sand lenses in sandy soils, and thickness of A and B horizons. The significance of the effect of the soil property on tree growth differed between species.Soil‐tree growth ratings are possible, but the precision is affected by the lack of significant site differences among soil taxa. Within soil taxa, variation should be recognized for some soil series.
Ion Mobilities and Electric Charge of External Clay Surfaces Inferred from Potential Differences and Osmotic Flow
Authors: Kemper W. D. , Quirk J. P. 
Published: July 2010

AbstractBentonite, illite, and kaolinite clays were compacted, made homoionic with various cations, and placed between chloride solutions of the respective cations of different concentrations. Rates of osmotic flow, electric potentials in the solutions and streaming potentials were measured across these compacted clay membranes. The osmotic flow was often from the high salt to low salt concentration side and was generally in the direction of more negative potential, indicating electroosmosis as the mechanism involved in osmotic flow. Diffuse layer theory was used to estimate the concentration ranges in which the measured external potential differences were not appreciably different from the respective potentials in solution inside the clay. Assuming the osmotic movement to be electroosmosis, the ζ potentials were calculated from the observed potential gradients and the osmotic flux. The portion of adsorbed cations participating in the diffuse portion of the double layer was then calculated from ζ. This “mobile” fraction of the adsorbed cations appears to decrease for multivalent cations as the equilibrium solution concentration decreased. La3+ kaolinite and Willalooka illites were positively charged and adsorbed Cl‐ as diffuse layers. The mobile fractions estimated by this method for bentonite are in reasonably good agreement with mobile fractions estimated from diffusion and conductance measurements.
Volatility of Organochlorine Insecticides from Soil: II. Effect of Relative Humidity and Soil Water Content on Dieldrin Volatility
Authors: Igue K. , Farmer W. J. , Spencer W. F. , Martin J. P. 
Published: July 2010

AbstractThe influence of soil water content and soil water loss on the volatilization of dieldrin, a representative weakly polar insecticide, was investigated to test the “codistillation” theory of pesticide volatility. Dieldrin volatilization from Gila silt loam was dependent on soil water content, but was not dependent on rate of water loss from the soil. Air relative humidity indirectly influences dieldrin volatilization by influencing soil water content. Dieldrin volatilization from moist soil was always at a maximum when soil water loss was zero. With air at 100% relative humidity, volatilization remained high, and only decreased gradually as the dieldrin concentration at the soil surface decreased. When air was at less than 100% relative humidity, volatilization decreased rapidly as the soil water content decreased and was essentially zero below a soil water content of 2.8%. The influence of soil water content and soil water loss on dieldrin volatility was similar at 20 and 30C, at 2 and 8 ml/sec flow rate and at 5 and 10 µg/g dieldrin concentration. The results show that soil water content influences pesticide volatilization by competing for soil adsorption sites and thereby controlling the vapor density of the pesticide. These experimental results offer conclusive evidence that for dieldrin and probably for all pesticides, the term “codistillation” does not apply to volatilization from soils.
Calcite Contributions by Earthworms to Forest Soils in Northern Illinois
Authors: Wiecek C. S. , Messenger A. S. 
Published: July 2010

AbstractCalcite spheroids and recognizable spheroid fragments originating in earthworm calciferous glands, contribute up to 56 kg/ha CaCO3 to the upper portions of the Al horizons of some forested, deeply‐leached soils. Horizons with a fresh pH from 6.3 to 7.5 may contain calcite spheroids; soil pastes of these horizons reach a pH between 7.2 and 8.0 upon incubation.The data are consistent with the hypothesis that the weathering of calcite spheroids is partly responsible for pH values in excess of 7.0 in the undried Al horizons of otherwise acid soils under forest cover.
Temperature Effects on Interlayer Potassium Exchange in Micaceous Minerals
Authors: Ismail F. T. , Scott A. D. 
Published: July 2010

AbstractThe potential range of temperatures that can be used with NaCl‐NaTPB solutions for the extraction of interlayer K in micaceous minerals has been established. Temperatures up to 45C proved suitable for all minerals and prolonged extraction periods. Higher temperatures have limited use, particularly with dioctahedral micas, because changes in TPB stability and KTPB solubility occur. For short contact periods, however, temperatures up to 105C may be used with trioctahedral micas.The release of K by dioctahedral and trioctahedral mica samples and by illite and soil fractions was determined with solutions that contained NaTPB to minimize K blocking and were maintained at 5, 25, or 45C. In coarsely‐ground samples of mica, where edge weathering was the dominant mechanism of K release, the rate of interlayer K exchange increased with the temperature. With finely‐ground mica samples there was no temperature effect on the initial release of K by layer weathering, but once K release by layer weathering was completed, temperature affected the rate of K release from small particles as well. Such differences in the effect of temperature on K release by edge and layer weathering provide a means of identifying the release mechanism involved in a particular mineral sample. Accordingly, it was found that fractions of Grundite, illite, and Marshall soil are unlike finely‐ground micas in that they do not release a major portion of their K by layer weathering. Changes in reaction temperature do not alter the limited degree of K exchange encountered with small mica particles.
Influence of Added Ca(OH)2 on Acidity in Submerged and Subsequently Dried Lateritic Rice Soils
Authors: Savant N. K. , Kibe M. M. 
Published: July 2010

AbstractTwo acid lateritic soils of the Maharashtra State (India), treated with increasing amounts of Ca(OH)2 equivalent up to about 92% total acidity (exchange acidity + pH‐dependent acidity) were submerged under water at room temperature (27 ± IC). Changes in soil pH were determined periodically during submergence. The soils were then air‐dried or oven‐dried and analysed for pH, exchange acidity, and pH‐dependent acidity. On 0‐day submergence, the addition of increasing amounts of Ca(OH)2 increased soil pH, but with time, the pH values of submerged soils converged in the neutral range of pH. The buffer curves of pH values of 30‐day submerged and subsequently dried soils against amounts of Ca(OH)2 added, indicated resemblance to that of weak acid titrated with weak base. The progressive neutralization curves of 30‐day submerged soils treated with Ca(OH)2 and then dried, showed that pH‐dependent acidity was neutralized concurrently with the neutralization of the major portion of exchange acidity. On addition of Ca (OH)2 equivalent to 92% of total acidity, exchange acidity was completely neutralized, whereas pH‐dependent acidity was not proportionately neutralized.
Salt Dispersion Coefficients Near an Evaporating Surface
Authors: Todd R. M. , Kemper W. D. 
Published: July 2010

AbstractA series of laboratory experiments was conducted to gain detailed information on water and salt movements near an evaporating surface.Columns instrumented with tensiometers and Richards' salinity sensors were used with coarse‐ and fine‐textured soils. Water was supplied to a water table at the base of the columns and approximately steady state evaporation from the soil surface was established. Dispersion coefficients were calculated from salt gradients and evaporation rates in regions of the soil where suctions ranged from 0.1 to several bars. Dispersion increased with increased solution flux and average solution velocity. Values obtained for dispersion coefficients corresponded closely with those obtained by other workers under more nearly saturated conditions at similar rates of solution flux.
Water Transmission Properties of an Asphalt Barrier
Authors: Palta J. P. , Blake G. R. , Farrell D. A. 
Published: July 2010

AbstractThe water transmission properties of an asphalt barrier were studied using samples taken from a barrier formed in Zimmerman fine sand. Steady flow experiments using a 9.0‐cm diameter soil column showed that water movement through the barrier was affected by the capillary potentials on both sides of the barrier if these potentials exceeded a critical value or ‘break point’ which ranged from −32 to −20 cm depending on the flow rate. When the potential below the barrier dropped below the critical value, the potential above the barrier remained relatively unchanged. This steady value increased from −4.3 to −1.5 cm when the flow rate was increased from 0.009 to 0.058 cm/hour. The hysteretic flow properties of the barrier are explained using a model based on the following assumptions: (i) flow occurs mainly through cracks of varying width, and (ii) the ratio of the draining to wetting potentials of the cracks exceeds unity and is independent of crack size.
The Effect of Bulk Density and Initial Water Content on Infiltration in Clay Soil Samples
Authors: Gumbs F. A. , Warkentin B. P. 
Published: July 2010

AbstractInfiltration measurements were made on swelling clay soil samples packed into columns. Small increases in bulk density over the range 1.10 to 1.25 g/cm3 markedly decreased the rate of water movement. The magnitude of the effect was greater for confined samples than unconfined samples at all initial water contents. A 1‐cm compact layer in the profile retarded water movement if the soil was confined. In partially confined samples the soil in the compact layer would swell on wetting, and water movement was retarded only when the bulk density after swelling still exceeded the bulk density of the remainder of the column. Bulk densities below 1.05 g/cm3, and heat of wetting in partially confined samples with 0% initial water content produced nonlinear distance to wet front vs. square root of time relationships. Comparison of horizontal and vertical infiltration showed that under these experimental conditions gravity contributed significantly to water movement at high initial water content.
Phosphate Fixation by Aluminum in Plant Roots
Authors: McCormick Larry H. , Borden F. Yates 
Published: July 2010

AbstractAlthough the exact physiological mechanism of Al toxicity is unknown, experiments have indicated that Al reduces the uptake of phosphates in plants. The suspected sites of Al‐phosphate interaction are within the root tissue and along the root surface. The present investigation was designed to identify by photomicrographic techniques the sites of phosphate fixation by Al within plant roots. Following pretreatment immersion of barley (Hordeum vulgare) and poplar (Poplus sp.) in solutions containing various concentrations of Al and phosphate, whole roots and sections of root tissues were selectively stained by using a modified Mo blue method to detect the location of phosphate. Color photomicrographs of the root section showed a definite interaction of Al and phosphate in the root cap and in the epidermal and cortical regions extending back from the root tip 1 to 5 mm. The Al‐phosphate interaction appeared to be associated with the cell wall and cytoplasmic membrane of the epidermal and cortical cells. Results also indicated that Al adsorbed by the root surface or in the intracellular free space may be capable of immobilizing phosphate present in the root tissue or in the external substrate.
Potassium Selectivity in Certain Montmorillonitic Soil Clays
Authors: Carson C. D. , Dixon J. B. 
Published: July 2010

AbstractPotassium selectivity (kG) was relatively constant when K‐saturation exceeded 15% for soil clays. As K‐saturation decreased from 15% or less, depending on the soil and clay fraction, kG increased exponentially. The 2 to 0.2µm clay fractions had high kG values to about 15% K‐saturation, apparently due to dioctahedral mica and vermiculite. Potassium selectivity for 0.2 to 0.08µm and <0.08µm soil clay fractions was below kG = 4.5 for about 85% of the exchange sites which corresponds to the montmorillonite contribution to cation exchange capacity (CEC) in these soil clays. Mica content correlated well with kG at a point near the steep part of the selectivity curves indicating the influence of small amounts of mica and possibly associated vermiculite on kG values. High kG values that occur over several percent K‐saturation in coarse soil clay fractions indicate that this fraction is more important than the more abundant finer fractions in controlling kG values and presumably K+ availability to plants. Increases in kG values for reference montmorillonites where only a few percent K‐saturation exists are attributed to mica and possibly vermiculite impurities. Dioctahedral mica and vermiculite appear to control K‐selectivity in the low K‐saturation range common in certain montmorillonitic soils.
Soil Water Depletion by A Hardwood Forest in Southwestern Wisconsin
Authors: Sartz Richard S. 
Published: July 2010

AbstractSoil water depletion by cut and uncut forest on a north slope was measured for 3 years with a neutron meter. Depletion by the uncut forest began early in the growing season at all depths measured and continued at a nearly constant rate until leaf fall. Seasonal depletion in a 1.5 m soil mantle averaged 188 mm on uncut plots, 87 mm on clearcut plots, and 57 mm on plots without vegetation. The amount of depletion increased with mantle depth; thus cutting had a greater water‐saving effect on deeper soils. Estimates of evapotranspiration by uncut forest agreed closely with empirical estimates of potential evapotranspiration.
Visual Recorder for Energize‐Deenergize Cycles
Authors: Benz L. C. , Doering E. J. , Dubuque D. E. 
Published: July 2010

AbstractAn inexpensive modification for an FW‐1 water stage recorder to provide a record of energize‐deenergize cycles is described. The system can be used in any equipment or process operation and provides a visual record of the performance.
Production of Permanganate Ion by Sodium Hypochlorite Treatment to Remove Soil Organic Matter
Authors: Anderson J. U. , O'Connor G. A. 
Published: July 2010

AbstractThe pink color characteristically produced during NaOCl treatment of soil to destroy organic matter was studied. Colored extracts were analyzed for Mn content and Redox potential. A spectrophotometer scan of one extract was compared with a scan of KMnO4 solution, and the extract color was shown to be caused by the MnO4‐ ion. The time of appearance and the intensity of the color were related to the organic matter contents of the samples. The source of the Mn was probably Mn(II) released from organic matter during oxidation. The MnO4‐ color appeared when the Redox potential shifted to about + 1.2 V, and was thus a reliable indicator of the approximate end of the organic matter oxidation process.
Ferruginous Concretions in a Poorly Drained Soil of Alberta
Authors: Pawluk S. , Dumanski J. 
Published: July 2010

AbstractInvestigations into the nature of a poorly‐drained soil pedon developed from acid shales in the Peace River region of Alberta, Canada, revealed the presence of ferruginous concretions in the A and B horizons. Concretions from both horizons were separated into two groups, magnetic and nonmagnetic. Magnetic properties were attributed to the preesnce of maghemite. This mineral was associated with iron oxides amorphous to X‐rays in the A horizon and with hematite in the B horizon. Iron oxide in nonmagnetic concretions from the A horizon was X‐ray amorphous while that in the B was crystallized as both goethite and hematite.Magnetic concretions from the A horizon showed dense areas when viewed in thin‐sections and contained less organic matter and oxalate extractable iron than the associated nonmagnetic concretions.An authigenic origin is suggested for the concretions.
Dynamic Measurement of Soil and Leaf Water Potential With a Double Loop Peltier Type Thermocouple Psychrometer
Authors: Chow T. L. , de Vries J. 
Published: July 2010

AbstractDetails on the construction, calibration, and performance of a three‐terminal double loop thermocouple psychrometer are given. (This psychrometer design was originally conceived and constructed by Dr. W. H. Gardner, Dep. of Agronomy, Washington State University, Pullman, Wash., USA). The thermal stability of this psychrometer is about 40 times better than that of the two‐terminal psychrometer (Spanner type) for ambient temperature fluctuations with a time rate of change greater than 0.2C/min. The response behavior of a fritted glass bulb and a ceramic bulb psychrometer was tested for vapor and for liquid phase water movement. For vapor phase flow the fritted glass bulb exhibited a shorter response time than the ceramic bulb psychrometer, whereas the reverse was true when water movement was predominantly in the liquid phase. Water potential measurements carried out on silty clay and silt loam soil samples were within ±0.4 bar of the porous plate extractor equilibrium values. A system that facilitates automatic and continuous in situ measurement of soil water potential using the three‐terminal psychrometer is described.
The Effect of Saturating Cations on the Adsorption of Dasanit®, O,O‐diethyl O‐[p‐(methyl sulfinyl) phenyl] phosphorothioate, by Montmorillonite Suspensions
Authors: Bowman Bruce T. 
Published: July 2010

AbstractA study was conducted to examine the adsorptive behavior of Dasanit in montmorillonite suspensions as affected by saturating cations and the clay suspension concentration. Adsorption isotherms, similar to Type III or Class “S” isotherms, were constructed for 10 cation‐saturated montmorillonites. Infrared spectroscopy was used to examine the relative polarities of the sulfoxide, sulfone, phosphoryl, and carbonyl groups as they occur in Dasanit, in some of its oxidation products, and in several other insecticides. Despite its polar nature, Dasanit did not appear to adsorb on the interlayer surfaces of montmorillonite. X‐ray diffraction data for dry Dasanit‐montmorillonite systems showed a maximum interlayer expansion of 2.7Å. Kinetic data showed that the adsorption process reached equilibrium in less than 15 min. The sequence of the upper linear segments of the 10 isotherms appeared to be related to valence, atomic weight, and co‐ordinating habits of the saturating cations. The Fe‐montmorillonite system adsorbed the most Dasanit. At a suspension concentration of 15 mg/ml, this system removed 99% of the Dasanit from solution. The maximum adsorption value obtained for Fe‐montmorillonite was 0.354 mg/mg clay at a suspension concentration of 0.25 mg/ml. This value corresponded to approximately 4.8 Dasanit monolayers on the exterior clay surface. Desorption studies indicated that those clays with the greatest adsorption capacity exhibited the least desorption tendency. The decreasing order of desorption was Na − > Ca − > Al − > Cu − montmorillonite.
Effects of Straw, Calcium Chloride, and Submergence on a Sodic Soil
Authors: Puttaswamygowda B. S. , Pratt P. F. 
Published: July 2010

AbstractThe effects of straw and CaCl2 during 130 days of submergence, and the effects of these amendments under submerged aerobic vs. anaerobic conditions for a period of 30 days were studied. Comparisons of pH, EC, Na, Ca + Mg, K, Fe, the optical density of the water extract, and ESP were used to evaluate the effects of these amendments. The straw and straw + CaCl2 treatments had the largest effect in lowering the pH and the ESP, increasing the Na and Ca + Mg concentrations and the EC. Submerged anaerobic conditions had the largest effect on promoting these reactions. The concentration of Fe2+ was highest in the straw treatments whereas CaCl2 had a depressing effect on the soluble Fe2+. The optical density was lowest in the straw plus CaCl2 amendment treated soil and the effect of this treatment was larger under anaerobic conditions.Wheat straw under anaerobic conditions caused an increase in the sum of Na plus Ca plus Mg that was about three times greater than the sum of these cations in the straw itself. In combination with CaCl2 wheat straw reduced the loss of Ca from solution observed when CaCl2 alone was added to soil.