bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Long‐Time Cropping on Hydrolyzable Organic Nitrogen Fractions in Some Great Plains Soils
Authors: Porter L. K. , Stewart B. A. , Haas H. J. 
Published: July 2010

AbstractVirgin soils and their long‐time cropped counterparts were hydrolyzed with HCl. The N separated into three fractions. The proportion of N that each N fraction contributed to the total N was altered when comparisons were made between virgin soils and their cropped counterparts. Cultivation and cropping caused losses in all three N fractions, however, the nondistillable acid‐soluble N fraction lost a greater proportion of its N than did the other two fractions.
Carbon Determination in Soils and Organic Materials with A High‐Frequency Induction Furnace
Authors: Young J. L. , Lindbeck M. R. 
Published: July 2010

AbstractApplication of established procedures for determination of carbon (C) in metals yielded about 60 to 90% C recovery from soils and pure organics. Systematic instrument and procedural changes showed that low recovery was due to escape of pyrolysis products or other volatile organic materials. Complete C recovery from dry soils and pure organics was achieved by adaptations employing an internal quartz‐enclosed graphite ignitor or an external auxiliary resistance furnace. The procedures also permit analysis of total C in residues from soil extracts or other solutions and for inorganic C and organic C in soils.
Moisture, Pore Space, and Bulk Density Changes in Frozen Soil
Authors: Krumbach A. W. , White D. P. 
Published: July 2010

AbstractIn the upper 15 inches of 2 frozen loam soils, one bare and one under alfalfa, moisture contents usually exceeded prefreeze field maximum. Total pore space was always above that before freezing; bulk density was predominantly less than the lowest expected prefreeze bulk density. Moisture changes in the frozen soils are attributed solely to internal moisture movement.
Terminal Elongation of Loblolly and Shortleaf Pine Seedlings under Soil Moisture Stress
Authors: Stransky J. J. , Wilson D. R. 
Published: July 2010

AbstractDuring the spring growth flush, height growth of potted seedlings was inhibited by soil moisture tensions not greater than 2 atm. and it stopped completely as tension increased to 3.5 atm. Incipient wilting of the young flush occurred near 5 atm. and all plants died at 15 atm. Leaf moisture content and corresponding leaf water deficit changed little before growth stopped. Water deficit was not a reliable indicator of the seedling's internal moisture regime once leaf moisture content fell from an initial 210% to below 105%.
The Movement of Water and Nitrate Around Bands of Sodium Nitrate in Soils and Glass Beads
Authors: Burns G. R. , Dean L. A. 
Published: July 2010

AbstractThe movement of water and nitrate (NO3‐) around bands of NaNO3 was studied in soils and glass beads in the laboratory. A hypothesis was developed and tested concerning the predominantly downward movement of NO3‐ from a band of NaNO3 in soils with moisture contents greater than field capacity. The hypothesis of events is as follows: Soil water moves, under the osmotic force generated, to the band of NaNO3; then the NaNO3 dissolves and diffuses away from the band. However, the effect of the diffusion is reduced when sufficient mobile water is present in the surrounding soil to maintain the influx of water. As a result, the NaNO3 solution accumulates in the vicinity of the band. Once the accumulating solution exceeds that which can be held by the capillary forces of the soil, the excess NaNO3 solution literally drops out of the band under the force of gravity. The drop‐out of NaNO3 solution continues until essentially all of the NaNO3 has been dissolved.This drop‐out phenomenon occurred in systems in which the water was present initially in quantities greater than field capacity, was moved through the system by leaching, or was moved into the system by capillarity from a shallow water table. Evidence supporting the details of the hypothesis resulted when various shields were used to alter the NO3‐ movement around the fertilizer bands under the leaching and “static” moisture conditions.
Profile of Natural Radioactivity in Hartsells Loam
Authors: Burton J. D. , Guenther W. B. , Owen H. M. 
Published: July 2010

AbstractDuring summer of 1961 bulk samples at 4‐inch to 30 inches depth increments were collected at 15 random locations within an apparently uniform single acre of forest soil, Hartsells loam, under oak‐hickory sawtimber on the Cumberland Plateau in Tennessee. Net radioactivity, total potassium content, and mechanical fractions were determined in the laboratory. After samples were stored in sealed containers for 7 days, activity was counted again and found to be increased. Linear regressions of initial activity on silt‐plus‐clay and on K, K on silt‐plus‐clay, and 7‐day activity on clay, on K, and on 1‐day activity were highly significant. Distributions of K, and of initial activity in the soil profile were more closely related to the profile of total fines than to the clay curve. Initial activity was believed to be due largely to K40, but activity gain during storage was probably due to daughters of U238.
Boron in Some Saline and Nonsaline Soils in Southeastern Saskatchewan
Authors: Werkhoven C. H. E. 
Published: July 2010

AbstractThe hot‐water soluble B content of salt‐affected chernozemic soils of southeastern Saskatchewan, determined colorimetrically with quinalizarin, was found to range from 0.1 to 2.0 ppm. Wheat and alfalfa were grown in the greenhouse on six different soils with three added levels of B. The mean B content of wheat ranged from 1.4 to 30.5 ppm., and that of alfalfa from 49.4 to 69.3 ppm. No toxicity symptoms were observed; on the contrary, the first level of added B tended to increase the dry matter yield of alfalfa on three soils. In a 34 factorial experiment, alfalfa and wheat were grown in the greenhouse on a saline soil with three levels of B, Ca, Mg, and Na. The dry matter yield of both crops decreased linearly with the application of 200 and 400 ppm. of Mg as MgSO4. Increased Na levels decreased the B content of wheat and the dry matter yield of alfalfa. Added Ca and Mg had no statistically significant effect on the B content of either wheat or alfalfa. The correlation between the B content of wheat and hot‐water soluble soil B content was highly significant (r = 0.689), but no such correlation was evident for alfalfa. In the case of wheat, the correlation appeared to be valid only for a specific soil type.
Iron or Aluminum Coatings in Relation to Sulfate Adsorption Characteristics of Soils
Authors: Chao T. T. , Harward M. E. , Fang S. C. 
Published: July 2010

AbstractStudies were conducted to investigate the effects of hydrous Fe‐ and Al‐oxides in relation to pH upon SO4 retention by Soils. “Less SO4‐retentive” soils exhibited SO4 adsorption of the Latosols or Ando soils after coating with the hydrous oxides. The pH‐dependent SO4 retention was much more marked after the coatings were applied. Retentive soils are made much less retentive by treatments for the removal of the hydrous oxides while the less retentive soils show appreciable SO4 adsorption when the hydrous oxides are added. In the acid range, the amount of SO4 adsorption is essentially proportional to the amounts of hydrous Fe‐ or Al‐oxides present. Aluminum‐oxides are more effective in retaining SO4 than Fe‐oxides when both are present as coatings on soil particles. The Fe system exhibited increasing adsorption with increased acidity whereas the Al system showed a maximum at pH 4.0. Subsequent decreases of SO4 adsorption by Al‐coated soils at lower pH values were shown to be associated with dissolution of the hydrous Al oxide phase.
Effect of Lime on Availability of Phosphorus in Zamorano Soils
Authors: Awan Abdul Bari 
Published: July 2010

AbstractField studies were conducted over a 2‐year period on experimental plots at the Escuela Agricola Panamericana situated in the valley of the Rio Yeguare at El Zamorano, Honduras, to study the effect of lime on the availability of soil P.Yields of corn (Zea mays), sorghum (Sorghum vulgare), beans (Phaseolus vulgaris), and cowpea (Vigna sinensis) green manure were recorded. Highly significant yield increased were obtained when the acid soil (pH 5.5) was limed to raise the pH to 6.5. The highest yields were obtained on plots receiving both lime and P.The major portion of the potentially available P in Zamorano soils is in the organic fraction. Analysis of the final soil samples showed that liming liberated the P locked up in the organic form and increased the efficiency of applied P for crop use.
Nutrient Utilization by Young Pitch Pine
Authors: Voigt G. K. , Richards B. N. , Mannion E. C. 
Published: July 2010

AbstractTen pitch pines (Pinus rigida Mill.) ranging in age from 5 to 9 years were excavated from an abandoned gravel pit in southern New Jersey. Lateral and vertical distribution of the root systems were recorded and total soil volume occupied by roots was calculated (root system sorption zone). In addition, the volume of soil within 1 cm. of any root surface was calculated (root surface sorption zone). Contents of total and exchangeable Ca and K in these zones were related to contents of Ca and K in the trees. Exchangeable Ca and K contents in the root system sorption zone were generally higher than the total content of these nutrients in the trees while the reverse was true for the relationship between the root surface sorption zone and the tree. Annual uptake of K by the trees was approximately equal to exchangeable K content of the root surface sorption zone. Annual uptake of Ca by trees was only about one‐third of the exchangeable Ca in the root surface sorption zone indicating that average distance of movement of Ca from soil to root surface was less than that for K. Less than 10% of the total soil volume occupied by roots was utilized in absorption of Ca and K.
Infiltration into Vertical Columns of Soil under a Small Positive Head
Authors: Gupta R. P. , Staple W. J. 
Published: July 2010

AbstractExperimentally measured soil moisture profiles during infiltration into vertical columns of air‐dry Grenville silt loam, under a small positive hydrostatic pressure, were compared with those predicted by the iterative procedure of Philip, and by an explicit finite difference method. Philip's solution predicted the shape of the drier portion of the moisture profile satisfactorily but the predicted depth of the zone of zero soil moisture tension and the total depth of infiltration were less than found experimentally. Satisfactory estimates of the shape and depth of the moisture profile were provided by the second method when the high conductivities in the saturated and transition zones near the surface were taken into account.
X‐Ray Spectrographic Analysis of Zinc, Manganese, Iron, and Copper in Plant Tissue
Authors: Dixon Joe B. , Wear John I. 
Published: July 2010

AbstractX‐ray spectrographic analyses for Zn, Mn, Fe, and Cu in Bermudagrass, pecan, pine, and corn foliage were made employing standard curves prepared from composite samples and from additions of the element to each sample. Interferences by various elements were determined by analysis of enriched samples. An increase in Cu concentration in Bermudagrass reduced the value obtained for Zn. First order Kα radiation was used for all elements except Cu. Interference of W Lα radiation occurred with Cu, but was reduced by using second order reflection of Cu Kα. Simplified techniques for preparing ground sample standards were examined. Results obtained by X‐ray spectrographic and chemical methods were found to compare satisfactorily in most cases.
Effect of Incubation Method and Storage Conditions on Nitrate Production of Incubated Soil Samples
Authors: Munro D. C. , MacKay D. C. 
Published: July 2010

AbstractSamples of Charlottetown fine sandy loam were incubated for 2 weeks at 30°C. and four different moisture tensions, with sand added in four different soil to sand ratios. Tension of 0.24 atm. and 1:1 soil‐sand ratio was optimum for production of NO3‐‐N. Incubation in an atmosphere of less than 85% relative humidity severely restricted nitrate production due to drying of the soil.Samples of the same soil at air‐dry, 10% and 20% moisture were stored at −20, −5 and +5°C. for 0.7, 3, 6, 9, 12, and 15 weeks in a complete factorial experiment, then incubated at 30°C. and 0.24 atm. moisture tension for 2 weeks. Air‐drying increased nitrate production by 15 to 20 ppm. N over moist samples. Storage at 20% moisture caused a 2 to 3 ppm. decrease compared to 10% storage. Minus 20° and −5°C. storage gave constant nitrate production with changing storage time, but −20° samples were 2 to 3 ppm. N higher than −5° samples at 10 and 20% moisture.Air‐drying soil from field capacity to the wilting point had little effect on nitrate production, but further drying to the air‐dry state caused a marked increase. Moisture content of soil samples during storage affected the correlation of nitrate production with ryegrass yields in the greenhouse.
Effect of Soil Temperature and Length of Reaction Period on Water Solubility of Phosphorus in Soil Fertilizer Reaction Zones
Authors: Beaton J. D. , Speer R. C. , Brown G. 
Published: July 2010

AbstractPellets containing 15 mg of P prepared from each of the following salts: KH2PO4 (MKP), NH4H2PO4 (MAP), (NH4)2HPO4 (DAP), Ca(H2PO4)2·H2O (MCP), and CaHPO4·2H2O (DCPD) were placed in cavities in the surface of Bradwell very fine sandy loam (pH = 7.8) and Monroe silt loam (pH = 5.8). The treated soils were stored at 5, 20, and 35C. Extent of dissolution of fertilizer pellets and development of soil‐fertilizer reaction zones were measured during the first 14 days of storage. At the end of 2, 7, 14, 28, and 56 days the soil‐fertilizer reaction zones were sampled and the concentration of water‐soluble P and the percentage of fertilizer P soluble in the reaction zones were determined.Rate of dissolution of the water‐soluble P fertilizers increased markedly as temperature increased. Some pellets were incompletely dissolved at the end of 14 days at 5C, whereas, at 35C dissolution was usually complete in less than 4 days. For each 15C increase in temperature there was about a 33% reduction in concentration of water‐soluble P and the proportion of fertilizer P soluble in water.During the first 14 days after adding the water soluble fertilizers there was a rapid decrease in concentration of water‐soluble P and proportion of dissolved fertilizer P while after 14 to 28 days the changes were much samller. Extraction of water‐soluble P decreased in the order MKP>MAP = DAP>MCP>DCPD>check. Differences among sources became smaller with increased time of contact with soil. DCPD was more soluble in the acid Monroe soil than in the calcareous Bradwell soil.
Surface Soil Textural and Potential Erodibility Characteristics of Some Southern Sierra Nevada Forest Sites
Authors: Willen Donald W. 
Published: July 2010

AbstractAnalyses of texture and potential erodibility were made on 208 samples of residual, upland forest soils collected at elevations from 6,500 to 8,000 feet in the southern Sierra Nevada in California. Multiple regression tests showed that soil texture and erodibility indexes were significantly related to variation in parent rock type, vegetative cover type, aspect, slope, and elevation. Prediction equations implied that granitic forest soils at high elevations may be twice as erodible as soils developed under similar soil forming conditions at low elevations.
Changes in Fiber‐Glass Soil Moisture‐Electrical Resistance Elements in Long‐Term Installations
Authors: England C. B. 
Published: July 2010

AbstractThe entrance of soil constituents into the interelectrode material of Colman soil moisture units causes changes in calibrated moisture‐resistance relations. The degree and abruptness of change is related to depth of placement in the soil. Regular field calibration checks must be performed in order to correct for these changes.
Description of Soil Characteristics for Partially Saturated Flow
Authors: King L. G. 
Published: July 2010

AbstractTwo empirical equations are presented for describing relative permeability as a function of capillary pressure. Of the two, Gardner's equation appears to fit the experimental data better and is easier to use because of its simple form. An equation is also presented for representing saturation as a function of capillary pressure. This equation is differentiable.The equations are used to calculate relative permeability and diffusivity as functions of saturation. The main utility of the equations is in the ease of handling input data and programming for numerical solutions, using digital computers. The equations may also prove useful in some theoretical studies where a wide range of possible soils may be described by changing a small number of parameters.
Relative Availability of Phosphorus in Fertilizers Varying in Solubility of the Phosphorus
Authors: Wright Bill C. , Murphy B. C. , Gilliam J. W. 
Published: July 2010

AbstractTwenty‐eight NPK fertilizers varying in solubility of the phosphorus were compared by band application and cropping to corn (Zea mays L.) in the greenhouse. Phosphorus uptake and per cent superphosphate equivalent were determined for each of two crops and for a combination of both crops. The per cent superphosphate equivalent ranged from 14 to 135 in the first crop, from 15 to 98 in the second crop, and from 13 to 111 for the total of both crops. Correlation coefficients for the relationships between superphosphate equivalent and water‐soluble and Netherlands alkaline ammonium citrate‐“available” P (NAAC‐“available” P) were highly significant for crop I, crop II, and the total of both crops. The correlation coefficients relating superphosphate equivalent to AOAC‐“available” P were barely significant at the 5% level. It is concluded from these results that both water‐soluble and NAAC‐“available” P are good criteria to use in judging phosphate fertilizer quality for crops and it is obvious that AOAC‐“available” P is poorly related to plant available P.
Quantity, Distribution, and Variability of Organic Matter and Nutrients in a Forest Podzol in New York
Authors: McFee W. W. , Stone E. L. 
Published: July 2010

AbstractThe organic matter under yellow birch‐red spruce forest (Betula alleghaniensis Britton‐Picea rubens Sarg.) growing on well‐drained, outwash sands of the Adams series was sampled intensively on eight one‐tenth acre plots in the Adirondack Mountains of New York. Under old, undisturbed stands the mean depth of the forest floor was 6.4 inches (16 cm) and the mean weight was 216,300 ± 8,800 (90% confidence interval) lb/acre (242 metric tons/hectare). There was approximately 175,000 lb/acre of organic matter in the forest floor and about 142,000 lb/acre in the upper three horizons of the mineral soil. The average bulk density of the forest floor was 0.14 g/cm3. A theoretical O horizon accumulation curve was drawn based on samples from plots having different ages of accumulation. These ages were inferred from ecological information and from evidence of fire history. The concentration of organic matter in the B2h horizon was positively correlated with age of the forest floor. The undisturbed forest floor contained approximately 2,850 lb/acre of nitrogen or about 43% of the estimated total in the nutrient cycle. It also contained approximately 150, 90, and 620 lb/acre of phosphorus, potassium, and calcium, respectively.Coefficients of variation ranged from .33 to .67, determined on the basis of 96 sample weights from the forest floor of each plot. Approximately 50 samples were needed to reduce the standard errors to 10% of the mean weights. Similar variability was found in the thickness of mineral soil horizons. Horizon thicknesses measured from a single soil pit in a 0.1‐acre plot were not reliable estimates of thicknesses when compared with those determined by taking 12 to 24 core samples spaced throughout the same plot.
The Dickson and Zanesville Soils of Washington County, Arkansas: I. Their Properties and Genesis
Authors: Rutledge E. M. , Horn M. E. 
Published: July 2010

AbstractThe Dickson and Zanesville soils of Washington County, Arkansas, exhibit very similar morphology although underlain by different bedrock. Purposes of this study were to determine certain chemical, mineralogical, and physical properties in order to establish their general composition and whether all or part of their sola were developed in loess. Data on three profiles of each series are similar. Some property ranges of their B22t horizons are: pH, 4.2 to 4.9; CEC, 12 to 16 meq/100g; base saturation, 14 to 27%; and clay content, 24 to 36%. Variations within series are of the same order as between series except the Zanesville has about 10% more fine or very fine sand and is usually somewhat lower in bases. A loess parent material is suggested by high silt contents (50% to 80%) and a lack of abundant coarse fragments in upper horizons. Conversely, uniform heavy mineral distributions and very fine‐to‐fine sand ratios with depth in both soils suggest that a definite upper loess layer does not exist and that Zanesville soils are mainly developed from underlying sandy siltstones and the Dickson soils from cherty limestone. It is postulated that porous cherts of the Boone formation can weather to silt as do siltstones. Since both are siliceous, similar soils could result.
Effect of Chemical and Mechanical Fallow Methods on Moisture Storage, Wheat Yields, and Soil Erodibility
Authors: Black A. L. , Power J. F. 
Published: July 2010

AbstractNeither complete chemical fallow (no tillage) nor combinations of chemical and mechanically tilled fallow methods resulted in more moisture conserved than conventional stubble‐mulch fallow. Grain yields (Triticum aestivum L., ‘Lee’ ‘Rescue’, or ‘Centana’) were highest on stubble‐mulch fallow, or other tillage plots receiving no spray at any time. Lowest moisture conservation and grain yields resulted from complete chemical fallow. Yields were lower even in the absence of visual residual effects of chemical treatments.Wind erodibility of the surface of complete chemical fallow soils was considerably lower than stubble‐mulch fallow. Complete chemical fallow methods increased surface residue cover at least 10% and significantly decreased the erodible fraction of the 0‐ to 2‐inch soil layer in comparison with stubble‐mulch fallow.
Tracing Soil Particle Movement with Fe‐59
Authors: Wooldridge David D. 
Published: July 2010

AbstractRates and patterns of actual soil particle movement were established by measuring changes in radiation intensity with time on an eroding sandstone soil. Applying 300 µc of Fe59 in a 5‐foot line along the contour gave a better measure of soil erosion pattern than 100 µc applied to a point. More than 70% of the isotope applied moved 3 or more inches downslope from the line of application. Apparently Fe59 forms mainly stable precipitates or reacts with existing ferric compounds on clay and silt particles because it is not found in the soil solution or on the soil base‐exchange capacity. Only 20% of the Fe59 was temoved by 72‐hour treatment with 30% H2O2. Over 90% of the Fe59 was retained in the surface 1 cm of soil.
Soil‐Peels and a Method for Estimating Biopore Size Distribution in Soils
Authors: Bouma J. , Hole F. D. 
Published: July 2010

AbstractSoil‐peels are thin blankets of soil taken in a nearly vertical position from the sides of soil pits. The soil‐peels are cemented on one side by cellulose acetate or vinyl plastic, and show dry colors and natural structure in three dimensions on the other more fragile side. Methods are described for taking soil‐peels in the field, and for systematically studying biopores in them with the aid of a binocular microscope.