bluuebunny/crossref_metadata_2025_split huggingface dataset:
Native Fixed Ammonium in Hawaiian Soils
Authors: Mikami David T. , Kanehiro Yoshinori 
Published: July 2010

AbstractNative fixed ammonium was found to range from 0 to 585 ppm. Volcanic ash soil horizons generally had a lower fixed ammonium content (4 to 178 ppm) than those from basalt (0 to 585 ppm). There was a general decrease of fixed ammonium concentration with depth in most of the profiles, this pattern of decrease being more pronounced in basaltic soils than in ash soils. Native fixed NH4‐nitrogen as a fraction of total nitrogen in individual horizons varied from 0 to 32.9%. This fraction was generally much greater in the basalt soils than in the ash soils. The soils did not show any definite pattern in the profile as to the relative amount of nitrogen present as native fixed ammonium. There was a highly significant relationship between native fixed ammonium and total K2O and percent mica in both ash and basalt soils. This relationship, however, does not apply to young, partially weathered soils containing primary potassium‐bearing minerals. The difference between organic C/organic N and organic C/total N ratios was generally greater in basaltic soils than in ash soils.
Two North Carolina Coastal Plain Catenas: I. Morphology and Fragipan Development
Authors: Nettleton W. D. , Daniels R. B. , McCracken R. J. 
Published: July 2010

AbstractTwo soil catenas of the Coastal Plain of North Carolina were studied. The older catena formed in feldspathic sediments and the wetter members have fragipans and bisequal profiles. The younger catena formed in quartz‐rich sediments and fragipans are absent in most soils. The younger catena has finer textured B horizons and thinner sola than comparable members of the older catena. The moderately well‐drained members of the two catenas are similar.
Soil and Plant Moisture Relations of Red Pine Growing on a Shallow Soil
Authors: Fisher R. F. , Stone E. L. 
Published: July 2010

AbstractThe relationship of plant moisture status to soil moisture content was studied in a 25‐year‐old red pine, Pinus resinosa Ait., plantation on 60 cm of channery silt loam soil over fractured siltstone bedrock. Two of the four‐tree plots received summer rainfall; rainfall was excluded from the remaining two plots by a plastic ground covering. The relative turgidity and needle moisture content of current‐ and second‐year needles were measured; only the second‐year needle relative turgidity was significantly correlated with soil moisture content. Wood moisture content was not correlated with soil moisture content. The dry weight of current‐year needles was closely related to the soil moisture availability during the period of growth. The degree to which the underlying bedrock was fractured, allowing roots to penetrate, was a primary factor in survival.
An Insoluble Manganese Ammonium Pyrophosphate Found in Polyphosphate Fertilizer Residues
Authors: Hossner L. R. , Blanchar R. W. 
Published: July 2010

AbstractSeventeen ammonium polyphosphates containing 5.0–5.8% Mn were reacted with a Selma silt loam soil. Fertilizer residues formed in this manner contained from 5 to 80% of the applied Mn. A highly significant correlation (r2 = 0.92) existed between the pH of the polyphosphate fertilizer and the percent of Mn which remained in the residue. Increasing pH resulted in increasing amounts of Mn at the site of placement. There was no consistent relationship between the nonorthophosphate content of the fertilizer and Mn in the residue.The Mn compound which preciptated in the residue was determined to be Mn3 (NH4)2 (P2O7)2 · 2H2O. It was the only Mn compound detected and was present in the 13 of the 17 polyphosphate fertilizers which had a pH greater than 2.5.
A Technique for Obtaining Undisturbed Soil Samples by Freezing in Situ
Authors: Blevins R. L. , Aubertin G. M. , Holowaychuk N. 
Published: July 2010

AbstractA freezing technique employing liquid nitrogen has been developed to freeze soil blocks in situ. This technique makes it possible to collect undisturbed samples from soils that are incoherent, have an abundance of roots or have a high percentage of coarse skeletal materials. The frozen blocks can be transported to the laboratory in a frozen state and eut into desired‐size blocks for bulk density, moisture retention and micromorphological studies.
Automated Determination of Magnesium in Soil Extracts by Atomic Absorption Spectrophotometry
Authors: Griffin G. F. 
Published: July 2010

AbstractA procedure for automated determination of Mg in soil extracts by atomic absorption spectrophotometry is presented. A modified Morgan solution (0.625N NH4OH + 1.25N CH3COOH, pH 4.8) was used to extract Mg from the soil. Measurement of Mg in 60 soil extracts by the proposed automated method gave results which were not different from those of an accepted manual procedure. Interferences with Mg absorbance caused by levels of Al, Si, and P higher than those found in most NH4OAc soil extracts were not great enough to necessitate use of a Sr diluent to eliminate the interferences.
Effect of Low Concentrations of Aluminum on Growth and Water and Nutrient Uptake by Cotton Roots
Authors: Lance J. C. , Pearson R. W. 
Published: July 2010

AbstractUsing a split root technique, the roots of 8‐day‐old cotton seedlings (Gossypium hirsutum ‘Empire’) were exposed to concentrations of 0, 0.15, 0.225, and 0.30 ppm Al for periods varying from ⅓ to 12 hours. Reductions in root weight and Ca uptake were the only effects observed after roots were exposed to 0.30 ppm Al for 1 hour. After longer exposures the uptake of water, Ca, Mg, K, P, and NO3 from ¼ Hoagland's solution was reduced. The curve of relative uptake vs. Al concentration was about the same in each case. The inhibition of Ca uptake was avoided by increasing the Ca concentration to 15 mM. Increasing the osmotic pressure did not accentuate the effect of Al on water uptake. The inhibition of all types of uptake indicates that the permeability of the plasmalemma is reduced. This might be due to interference in a function of Ca.
Independent Measurement of Matric and Osmotic Potential of Soil Water
Authors: Oster J. D. , Rawlins S. L. , Ingvalson R. D. 
Published: July 2010

AbstractA technique is described that uses the operating principles of the thermocouple psychrometer and the porous plate apparatus to measure the matric and osmotic potentials of soil water without extraction of a significant amount of soil solution. The technique was tested on a Na‐saturated Gila soil to which NaCl solutions with osmotic potentials of −1, ‐2, and −6 bars were added. The standard error of measurement of the soil water potential components was ±0.04 bar. The measured osmotic potentials of the soil were lower than those of the added solutions, which can be explained by salt exclusion although mineral dissolution could contribute to these results. The technique also permitted measurement of the partial molar volume of soil water with an accuracy of about ±1%. Within this precision, the partial molar volume of soil water in this study was shown to be the same as that of pure water.
Relation of Water Application to Evaporation and Storage of Soil Water
Authors: Gardner H. R. , Gardner W. R. 
Published: July 2010

AbstractEvaporation was measured from columns of Rago loam and McGrew loamy sand, to which water had been added at several rates ranging from 0.25 cm/day to 10.2 cm every 20 days. The water lost by evaporation varied from 100% of the total applied for the smallest and most frequent addition to 31.2% for the 10.2 cm of water added to McGrew soil every 20 days.The losses from repeated cycles of the individual treatments tended to approach a constant value that was less than the potential loss. As the amount added was increased for a given evaporation period, the loss tended to approach a constant value that also was much less than the potential loss.The cumulative evaporation curves were scaled to dimensionless variables and compared with a theoretical solution of the diffusivity equation for finite media. Using this scaling‐comparison technique, the losses from soil with two different potential evaporations were compared with predicted curves.
Quantitative Evaluation of the Strong‐Force Model for Expansion and Contraction of Vermiculite
Authors: Kittrick J. A. 
Published: July 2010

AbstractThe model used considers expanding forces arising from hydration of positive interlayer ions, negative charge sites, and vermiculite surface. Opposing the hydration forces is the electrostatic contracting force between positive interlayer ions and negative charge sites.The contribution of each force to net thermodynamic values is considered independently of other forces. Hydration of interlayer cations may then be estimated from values for bulk solution. Hydration of the negative charge sites is estimated from the entropy change during interlayer water sorption by Na vermiculite. Hydration of the vermiculite surface is estimated from the enthalpy change for wetting of an oxygen‐silicate surface. The contribution of the electrostatic contracting force is estimated from the lattice enthalpy of an ionic structure containing the interlayer cation and an anion equivalent to the negative charge site.The thermodynamic estimates based upon the model are in qualitative agreement with water sorption by Li, Na, K, Rb, and Cs vermiculites and are in quantitative agreement with Na vermiculite. These are the only comparisons with the experiment possible at present. Agreement was dependent upon strong hydration of negative charge sites.The model and the thermodynamic estimates suggest a mechanism for fixation of ions by vermiculite. The hydrating and electrostatic forces appear to be rather closely balanced, resulting in a relatively small enthalpy change favoring water sorption. This permits the entropy contribution from interlayer water molecules, which favors desorption of water, to drive the vermiculite system to spontaneous contraction, fixing interlayer ions such as K+.
Experimental Study of the Influence of the Partial Pressure of Carbon Dioxide on the pH Values of Aqueous Carbonate Systems
Authors: Ponnamperuma F. N. , Castro Ruby U. , Valencia Carmen M. 
Published: July 2010

AbstractThe pH values of 0.001N and 0.01N solutions of sodium carbonate and of aqueous suspensions of CaCO3, MnCO3, and FeCO3 equilibrated at 25C with CO2‐N2 mixtures containing 1–100% CO2 conformed to the equations, pH = 7.85 + log Na+ − log Pco2 + log γhco3‐ and pH = K − ⅔ log Pco2 + ⅓ log γhco3‐ − ⅓ log γm2+, respectively. Suspensions of sodic and calcareous soils, equilibrated similarly, behaved like the corresponding simple systems, while reduced soils high in active iron yielded a pH‐log Pco2 relationship almost identical with that obtained experimentally with an aqueous suspension of Fe3(OH)8.
Soil Scientists' Proficiency in Describing Soil Consistence
Authors: Nettleton W. D. , Holzhey C. S. , Flach K. W. , Brasher B. R. 
Published: July 2010

AbstractA recent field trip for a group of soil scientists from the western United States permitted comparison of professional soil scientists' description of dry and moist soil consistence and comparison of the descriptions of consistence with unconfined compressive strengths of dry soil.Field party members agreed fairly well with each other in the description of the consistence of moist soils (60% agreement) and dry soils (70% agreement). There was a logarithmic relation between their description of dry consistence and unconfined compressive strengths. The unconfined compression test thus seems to provide a suitable soil consistence standard. The range in unconfined compressive strengths within classes increases from the slightly hard to the very hard classes.
Fractionation of Phosphorus in Lake Sediments: Analytical Evaluation
Authors: Frink C. R. 
Published: July 2010

AbstractMethods for the fractionation of P in soils were evaluated in the fractionation of P in lake sediments. Both Al‐P and Fe‐P may be determined readily and precisely by the Chang and Jackson procedure. Reductant‐soluble P was more difficult: modifications of a citrate oxidation procedure utilizing KMnO4 produced an acceptable method. Large amounts of Fe in the Ca‐P extracts caused low results, but this was overcome by limiting the aliquot size. Organic P determined by difference between total and inorganic P was not related to the organic matter content of the sediments. An alternative measure of inorganic P, obtained by summing the inorganic P fractions, yielded values for organic P which were correlated with organic matter.
Effect of Chloride Salts on Ammonium Nitrogen Release in Two Hawaiian Soils
Authors: Singh B. R. , Agarwal A. S. , Kanehiro Y. 
Published: July 2010

AbstractAkaka silty clay and Wahiawa silty clay were treated with the chloride salts of mono‐, di‐, and trivalent cations. Carbon dioxide production in salt‐treated samples was slightly less than in the control. NH4‐N release was a direct function of salt concentration and length of incubation. Once the NH43 ions were formed from soil organic‐inorganic complexes, the different cations had a second and larger effect on the exchange reaction which transferred the NH4 ions from surface sites to the soil solution. The equilibrium state of the exchange reaction was largely dependent on the nature and concentration of cations in the soil solution, as well as on the length of incubation.A consideration of the overall effect of cations on NH4 release in the two soils led to the series, Al > Fe > Ca > Mg > K > Na, in order of decreasing NH4 replacing power. However, the series was applicable only to a concentration of 0.1M. At higher concentrations, Al and Fe ions were believed to be complexed in the soil and were thereby inactivated. The added salts had little or no effect on NO3‐N content of the two soils.
Effect of N, P, and K Fertilization on the Mineral Composition of Tobacco
Authors: Peterson L. A. , Dolar S. G. , Chesters G. 
Published: July 2010

AbstractThe effect of N, P, and K fertilization on the mineral composition of tobacco leaves (Nicotiana tabacum L.) was evaluated under field conditions for three cropping seasons. The amounts of added N, P, and K had a highly significant effect on the leaf concentrations of Ca, Mg, B, Zn, Cu, Mn, and Al and a significant effect on Fe concentration. Correlations between the concentrations of N, P, and K in the leaves and concentrations of the other mineral components of the leaf were similar to those for added N, P, and K.Nitrogen had a direct effect on Mg and Mn and an inverse effect on B concentrations in the tobacco leaves. Phosphorus had a direct effect on Ca, Mg, and B and an inverse effect on Zn and Cu. Potassium had an inverse effect on Ca, Mg, B, Zn, and Cu. Although not all coefficients were significant, K was inversely correlated to all eight mineral elements.
Influence of Silicie Acid on Uptake of Mn, Al, Zn, and Cu by Tomatoes (Lycopersicum esculentum) Grown on an Acid Soil
Authors: Peaslee D. E. , Frink C. R. 
Published: July 2010

AbstractTreatment of an acid Merrimac fine sandy loam with H2SiO3 significantly decreased the concentration and total uptake of Mn and Al in tissues of greenhouse grown tomatoes (Lycopersicum esculentum) but affected neither the uptake nor tissue concentrations of Cu or Zn. Yields of dry matter were not significantly increased by Na2CO3 treatments. Increases in yield of dry matter were more closely associated with decreased concentrations of Zn and Cu and less closely associated with decreased concentrations of Al and Mn.
Regional Distribution of Potassium in the B Horizon Clay of Some Prairie Loess Soils of the Midwest
Authors: Wells K. L. , Riecken F. F. 
Published: July 2010

AbstractTo test the hypothesis that K content of Iowa soils was related to soil development, samples from the B horizon of selected sites were obtained from loess‐derived prairie soils at several locations within the state. Samples were also obtained from Nebraska and Illinois loess soils to relate the Iowa study to the midwestern prairie region. Total K in clay from the B horizons decreased progressively from west to east. This was explained on the basis of concurrent increase in average annual precipitation from west to east across the area. No consistent relationships between total K content and standard indexes of profile development were obtained. However, K was highly correlated with depth to the B horizon. Although montmorillonite was the dominant clay mineral in all samples, there was relatively more illite in samples of higher K content and from sites receiving lesser amounts of annual precipitation. Studies of K released to sodium tetraphenyl boron (NaTPB) on Iowa soils reflect the trends in total K content found in the B horizons.
Entrapped Soil Air in a Field Site
Authors: Garner Dale E. , Donaldson John K. , Taylor George S. 
Published: July 2010

AbstractSoil air was entrapped at 50–100 cm of water pressure in a wooded field site due to infiltrating water. The air was expelled through piezometer tubes for 2 or 3 months following spring rainfall. Seven additional sites did not exhibit this phenomenon, which appears to be caused by a favorable combination of soil and vegetative factors.
Bentonite Stabilization of Soil to Resist Wind Erosion
Authors: Hsieh J. J. C. , Wildung R. E. 
Published: July 2010

AbstractPreliminary investigations indicate that the addition of bentonite to soil followed by moistening will significantly reduce the susceptibility of the soil to wind erosion after drying. This effect persists after rupture of the aggregates originally formed through bentonite amendment provided the soil is remoistened.
The EMF of Platinum Electrodes in Dilute Solutions and its Relation to Soil pH
Authors: Bohn H. L. 
Published: July 2010

AbstractAn equation is derived for mixed potentials of electrodes which explains their non‐Nernstian behavior in dilute solutions and at nonequilibrium conditions. Adding iron(II) sulfate to soil suspensions resulted in EPt/pH slopes which were unrelated to the reaction taking place because EPt is a mixed potential and because the pH is governed to a significant extent by non‐redox reactions.
Gaseous Products Produced by Anaerobic Reaction of Sodium Nitrite with Oxime Compounds and Oximes Synthesized from Organic Matter
Authors: Porter Lynn K. 
Published: July 2010

AbstractHydroxylamine was reacted with a number of soil organic matter sources to produce organic matter oximes. This reaction has been used to measure the carbonyl groups in organic matter. The soil organic matter, organic matter oximes, oxime compounds, and aromatic compounds were reacted with buffered (pH 5.0 and pH 6.0) NaNO2 solutions in evacuated Rittenberg tubes. The gaseous products resulting from these nitrate reactions were analyzed by gas chromatography and compared to determine the nature of soil organic matter oximes and to determine if such oximes could be a source of N2O production in soils. All oxime compounds studied, except dimethylglyoxime and the quinone oximes, which produced NO, formed N2O as their major gaseous products. The major gaseous product from organic matter oximes, organic matter, and aromatic compounds was NO. The results suggest that if the reaction product of NH2OH and organic matter is an oxime, the oxime resembles or reacts like quinone oximes or dimethyl‐glyoximes. The negligible amounts of N2O produced from the reaction of NaNO2 with organic matter oximes suggests that this is probably not a pathway for N2O loss from soils.
Observations on Opal Phytoliths in a Soil Biosequence in Southeastern Minnesota
Authors: Verma Shive D. , Rust R. H. 
Published: July 2010

AbstractThe content of opal phytoliths was measured in selected horizons of six soils from Goodhue County, Minn. The highest amount of opal phytoliths occurred in a Typic Hapludoll (Kenyon series) suggesting a soil developed under dominant grass vegetation because most of the opal is derived from big bluestem (Andropogon gerardi L.) and little bluestem (A. scoparius L.). Opal phytoliths isolated from some horizons were similar in morphology to reference slides made of opal from burr oak (Quercus macrocarpa Michx.), ironwood (Ostrya virginiana (Mill.) K. Koch), and a shrub, hazel (Corylus americana Walt.).Opal phytoliths in two associated Aquollic Hapludalfs (Kasson and Taopi series) were derived primarily from big and little bluestem and with minor amounts from trees. This suggested at least a period of forest vegetation. A striking feature of Kasson, Kenyon, and Taopi soils is the higher content of opal phytoliths in till material II which begins in the B2 horizon at depths of about 50 inches. Possibly at one time the top of material II might have been prairie covered landscape and the overlying silty material was deposited later.
Infiltration and Water Depletion in Lysimeters
Authors: Qashu Hasan K. 
Published: July 2010

AbstractEvapotranspiration losses from five lysimeters with different plant species were estimated. Prediction equations were developed and used to estimate soil water regimens, infiltration and runoff in lysimeters with vegetative cover. Calculated soil water contents and runoff for lysimeters with five different plant species were good estimates of measured quantities.
Comparison of Computed and Measured Moisture Redistribution Following Infiltration
Authors: Staple W. J. 
Published: July 2010

AbstractRedistribution of water was measured in three soils following two different initial amounts of infiltration. The measured redistribution profiles were compared with those computed from the flow equation taking into account hysteresis in the drying tension vs water content relationship. Agreement between measured and computed moisture profiles was considered satisfactory. A procedure was outlined for determining wetting diffusivities and conductivities in the wetting front on the basis of soil moisture profiles obtained during redistribution. The different shapes of the drying scanning tension curves provided some insight into the differences in particle size distribution that influence the water‐holding capacity of soils.
Effect of Chelating Agents on the Availability to Plants of Carrier‐Free 59Fe and 65Zn Added to Soils to Simulate Contamination From Fallout
Authors: Wallace A. , Mueller R. T. 
Published: July 2010

AbstractCarrier‐free 59Fe and 65Zn were added to Dinuba fine sandy loam (neutral), Hacienda loam (calcareous), and Yolo loam (slightly acid), and equilibrated through drying and wetting cycles. Bush bean (Phaseolus vulgaris L., var. ‘Improved Tendergreen’), corn (Zea mays L., var. ‘Golden Cross Bantam’), and soybean (Glycine max Merr., var. ‘PI‐54619‐5‐1’ and ‘Hawkeye’) were grown in 59Fe‐containing soil and bush bean (P. vulgaris L.), corn (Z. mays L.) and cotton (Gossypium hirsutum L., var. ‘Acala 442’) were grown in 65Zn‐containing soil. One‐half of those with 59Fe received Na2EDDHA equivalent to 4.4 kg of Fe/ha had there been a 1:1 metal chelate and one‐half of those with 65Zn received Na2EDTA equivalent to 5.5 kg of Zn/ha had metal been added with the chelating agent. The chelating agents had many different effects depending on soil and on crop. Chelating agents increased the specific activity of 59Fe in the bush bean and soybeans. The specific activity of 59Fe in corn was unchanged by chelating agent but was much higher than in bush bean and soybean with or without chelating agents. When carrier Fe was added, the behavior of 59Fe was essentially unchanged. The specific activity of 65Zn in plants in most cases was increased by the EDTA. The EDTA increased both 65Zn and total Zn in corn, but the specific activity generally was unchanged by the chelate.