bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Chlorite‐Like Mineral in Indiana Soils
Authors: Klages M. G. , White J. L. 
Published: July 2010

AbstractA clay mineral with basal spacing of approximately 14Å is a constituent of many Indiana soils. The properties of a sample of this mineral separated from Crosby silt loam were studied.During the weathering of the soil profile, the pH decreased and the 14Å mineral replaced illite as the dominant clay mineral. In similar size fractions of clay, the potassium content decreased from the C to the A horizon, while the cation‐exchange capacity remained practically unchanged.X‐ray diffraction and other procedures were used to determine the properties of the 14Å mineral and the effect of various treatments on these properties. Many of its characteristics were found to be similar to those reported for dioctahedral vermiculite. Several of the reactions suggested positively charged, partially hydrated aluminum hydroxide rather than hydrated exchangeable aluminum ions as the interlaying material.It was concluded that during weathering of illite, aluminum can replace potassium between the clay plates. The form of this interlayer aluminum is probably influenced by soil pH. A suggested general formula is:
urn:x-wiley:03615995:saj2sssaj195703615995002100010005x:equation:saj2sssaj195703615995002100010005x-math-0001 where x varies with soil pH. Dioctahedral vermiculite and dioctahedral chlorite could thus form a continuous series.
Replaceability of Ammonium Fixed in Clay Minerals as Influenced by Ammonium or Potassium in the Extracting Solution
Authors: Hanway J. J. , Scott A. D. , Stanford G. 
Published: July 2010

AbstractFixed NH4 in vermiculite and bentonite was completely released by distillation in NaOH solutions. Small amounts of K in the solutions, however, blocked this release of NH4. If the amount of K was in excess of 2 K ions per 100 Na ions, no fixed NH4 was released from vermiculite. With smaller amounts of K present, the amount of fixed NH4 released decreased as the K/Na ratio in solution was increased. In an equilibrium NaCl extraction, small amounts of either fixable ion, NH4 or K, in the solution prevented the release of fixed NH4. There was no blocking from the NH4 in the NaOH distillations since it was lost from the alkaline systems. In the salt solutions, NH4 was more effective than K in blocking the release of fixed NH4. The blocking effect of a gixen fixable/nonfixable ion ratio in the neutral salt solutions increased as the amount of salt extractant per gram of mineral was increased. This is due to the preferential adsorption of the fixable cations. Higher K/Na ratios were required to block the release of fixed NH4 in neutral salt solutions than in alkaline solutions. Ten K ions per 100 Na ions in NaCl were not as effective as 2 K ions per 100 Na ions in NaOH. Higher K/Na or NH4/Na ratios were required to block the release of fixed NH4 from bentonite than from vermiculite. The NH4/Na ratio required to completely prevent the release of fixed NH4 from bentonite by NaCl was 0.04 as compared to 0.02 for vermiculite.
Effect of Douglas‐Fir Sawdust Mulches and Incorporations on Soil Microbial Activities and Plant Growth
Authors: Bollen W. B. , Lu K. C. 
Published: July 2010

AbstractSawdust and other wood wastes applied to soil may retard plant growth by inducing nitrogen deficiency but these effects with Douglas‐fir are less pronounced than with many other residues of wide C:N ratio. While Douglas‐fir wood is extremely low in nitrogen it is low also in available carbon. The predominating lignin‐cellulose complex is resistant and only slowly metabolized, enabling a minimum amount of nitrogen, repartitioned among successive crops of microbes, to suffice for long‐continued decomposition.Sawdust showed no direct toxicity and had little effect on soil pH. Resins and other extractives were readily decomposed. Apparent decomposition percentages based on 50 days CO2 production without added available nitrogen in soil respiration experiments were: for dextrose 60, wheat straw 48, red alder 40, ponderosa pine 33, western red cedar 33, Douglas‐fir 30, pitch 30, western hemlock 27, bark 26, and lignin 6%, respectively. Although added nitrogen fertilizer hastened decomposition of organic matter having wide C:N ratio, it commonly depressed cumulative CO2 evolution in soil respiration.Greenhouse and field studies indicate that to avoid induced nitrogen deficiency 5 to 10 pounds of nitrogen per ton of sawdust are generally sufficient during the first year; nitrogen additions the following 2 or 3 years may be successively halved. Douglas‐fir sawdust without added nitrogen often causes no retardation and in some cases significant increases of certain crops such as sunflowers and strawberries. Corn appeared much more sensitive to nitrogen deficiency. All wood wastes and cereal straws at 100 tons per acre have been found to depress plant growth unless nitrogen is added.
Residual Effects of Various Phosphates as Measured by Yields, P32 Uptake, and Extractable Phosphorus
Authors: Ensminger L. E. , Pearson R. W. 
Published: July 2010

AbstractIn 1930 an experiment was started on a Decatur silt loam and on a Greenville fine sandy loam to compare the effectiveness of different sources of phosphorus for crops grown in a rotation of corn and cotton with vetch. At the end of 16 years, phosphate applications were discontinued in order to study residual effects on yields. In 1950 and 1951, tagged superphosphate was applied to all treatments and available phosphorus, based on P32 uptake, was calculated and expressed as A values.Yield data from both locations show that all sources had considerable residual effects. For any particular source, the residual effect was in proportion to the amounts that had been added. Basic slag gave the greatest residual effect on the Decatur soil as measured by vetch and cotton yields. It also gave the greatest residual effects on the Greenville soil as measured by cotton yields. Tricalcium phosphate and raw phosphate showed a much greater residual effect, as indicated by vetch yields, in the Greenville soil than in the Decatur soil.A values show that all sources had considerable residual effects as measured by radiophosphorus uptake. The A values for basic slag at both locations were larger than for an equivalent amount of any other source. For the Greenville soil, A values show that superphosphate had a greater residual availability than rock phosphate applied at twice the rate of P2O5. However, A values on the Decatur soil indicate that rock phosphate had about the same residual availability as superphosphate applied at an equivalent rate of P2O5. For any particular source, A values were in proportion to the amounts which had been added.Yield data for the first 4 years of the residual period show only a very general relationship with A values when all sources are considered together. However, correlation coefficients show a fairly close relationship between yields and A values in most cases when the analysis is limited to rates of one source.Extractable phosphorus data show that phosphate applications resulted in phosphorus accumulation and that the amount accumulated was proportional to the rate of application.
The Effect of Soil Potassium Levels on Yield, Lodging, and Mineral Composition of Corn
Authors: Boswell Fred C. , Parks W. L. 
Published: July 2010

AbstractFive corn hybrids (three single crosses and two double crosses) were grown on a soil low in exchangeable potassium. Four potassium fertility levels were used. K, Ca, Mg, and P were determined on leaf samples collected periodically throughout the growing season. Root lodging and stalk breakage were also determined periodically. A significant yield increase from the first increment of K2O was obtained, but no further increase was obtained from additional increments. Significant yield differences among corn hybrids were obtained. Potassium fertilization significantly decreased both root lodging and stalk breakage. The corn hybrids were found to differ significantly in their root lodging and stalk breakage characteristics.The potassium content of the plant increased with increased rates of potassium fertilization. The maximum potassium content of the plant was observed during the early stages of plant growth and the potassium content decreased percentagewise as the plant neared maturity. The calcium and magnesium contents of the leaf tissue were generally inversely related to the potassium content of the plant. The phosphorus content was unaffected by the potassium fertility treatments. The milliequivalents of total cations (K, Ca, Mg) per 100 g. of over‐dry tissue (1) decreased at a given stage of plant growth as the rate of potash fertilization increased, (2) increased with age of plant at the lower potassium levels, and (3) remained essentially constant throughout the life of the plant at the highest potassium level. The sum of the percent K, Ca, and Mg content of the plant was essentially a constant at all stages of growth.
Ridged Rows and Winter Cover Crops in Tobacco Production
Authors: Britt C. S. , Slater C. S. 
Published: July 2010

AbstractRidged rows and winter cover crops were used to control erosion and promote good tilth in 1‐year tobacco rotations. Studies conducted over a 5‐year period comparing flat cultivation versus ridged rows showed that tobacco yields were increased substantially by ridging in wet years. In dry years, yields on ridged and flat plots were essentially the same.Winter cover crops and their management affected both the yield and quality of the succeeding tobacco crop. Ryegrass alone reduced yield and vetch alone lowered quality. Highest yields and quality of tobacco followed mixed cover crops of rye and vetch or ryegrass and vetch.Late turning of the mixed cover crops was better than early turning. Aside from supplying more organic residues to the soil, late turning promoted the larger yield of tobacco, of as good a quality as early turning.
Use of Acid‐Fluoride Solutions for the Extraction of Available Phosphorus in Calcareous Soils and in Soils to Which Rock Phosphate Has Been Added
Authors: Smith F. W. , Ellis B. G. , Grava J. 
Published: July 2010

AbstractIn the chemical measurement of “available” phosphorus in calcareous soils from western Kansas, it was found that a method involving use of a solution of 0.025N HCl and 0.03N NH4F worked very well. It was necessary to use a large volume of solution to effect accurate measurement of available phosphorus. Neither dilute acid alone nor 0.1N HCl plus 0.03N NH4F proved satisfactory. Use of 0.5M NaHCO3 buffered at pH 8.5 was not as satisfactory as the use of dilute acid and fluoride as mentioned above. It was better than the other techniques, however.Addition of fluoride to dilute acid (0.025N HCl) repressed the solubility of certain forms of phosphorus found in calcareous soils which were extracted by acid alone. Apparently the portion of the phosphorus not repressed by fluoride, insofar as its solubility is concerned, corresponded rather closely to that which was usable by wheat plants. Therefore, good agreement was obtained between this method of chemically extracting available phosphorus and plant growth response to added phosphorus. Addition of 1.0N CaCl2 to the extracting solution, as a substitute for fluoride, did not aid materially in improving the usefulness of dilute acid solution as a means of extracting “available” phosphorus. It did repress somewhat the solubility of phosphorus, however.The acid‐fluoride combination (0.025N HCl + 0.03N NH4F), most acceptable for use with the calcareous soils, also was adapted for use with soils from central and eastern Kansas, most of which were acid in reaction. This method of extracting phosphorus was useful in evaluating availability of phosphorus in either untreated soils or in soils after the addition of rock phosphate. Likewise it was useful in measuring the release of phosphorus from rock phosphate to forms in the soil which may be regarded as available for plant utilization.Extraction of phosphorus from pure chemical compounds by means of the dilute acid‐fluoride technique provided additional information.
Ring Growth of Plants
Authors: Harper W. G. 
Published: July 2010

AbstractThis paper discusses the spectacular rings formed among stands of ringgrass (Muhlenbergia torreyi) and mentions that this type of growth occurs in many places and among many plants in the arid and semiarid Southwestern States. Brief physical and chemical characteristics of soils where ring growth occurs are given and speculations are made about conditions that contribute to formation of the rings.
Some Meteorological Aspects of Evapotranspiration
Authors: Halstead Maurice H. , Covey Winton 
Published: July 2010

AbstractDuring the past decade increasing attention has been given to various engineering type equations designed to estimate, from available climatic data, the amount of water used by plants.Some of the basic assumptions involved in these equations are examined in the ligh to frecent advances in knowledge of the physical processes at the earth‐atmosphere interface.It is found that the majority of equations involving the concept of potential evapotranspiration or consumptive use tend to assume a homogeneous soil moisture regime infinite in horizontal extent. Therefore, it has been difficult to apply these equations to irrigation practice, which obviously must create isolated areas of above normal moisture.Consequently, the problem is approached from the strictly physical point of view, and it is shown that a solution can be obtained, provided that sufficient knowledge of soil interactions is available.
Rate of Loss of Carbon from Georgia Soils
Authors: Giddens Joel 
Published: July 2010

AbstractThe organic content of forest soils in Georgia was found to be rapidly lowered by cultivation. A mean decrease from 3.29% organic matter to 1.43% was found upon sampling 29 locations of forest soils and adjoining areas cultivated 25 years or more. A 20% average reduction in carbon occurred for 6 forested Piedmont soils brought under simulated cultivation for 24 months.Most of the carbon from green oats, crimson clover, and barnyard manure was lost in 24 months when added to cultivated Cecil soil at rates of 20 tons per acre. Sawdust and mature oat and wheat straw were more resistant. But even these materials decomposed fairly rapidly with simulated cultivation.The 20,000‐ and 40,000‐pound application rates of green oats only slightly increased soil carbon after 12 months, and after 24 months only the 40,000‐pound rate was higher (but not statistically) than the control. Rates of 2,000 and 5,000 pounds of green oats resulted in a slight decrease of soil carbon over the control after 24 months (but this was also not statistically significant at the 5% level).
The Effect of Drainage on the Weathering of the Clay Minerals in the Allenwood Catena of Pennsylvania
Authors: Johnson L. J. , Jeffries C. D. 
Published: July 2010

AbstractThe clay minerals from each horizon of a poorly‐drained and well‐drained member of the Allenwood catena were examined by X‐ray methods. In both drainage members the weathering sequence found was: mica (illite) → mica intermediate → vermiculite → chlorite‐like. Apparently, drainage conditions controlled the degree of expression of this weathering sequence in the two soils investigated.
Transmission of Gamma Radiation by Soils and Soil Densitometry
Authors: van Bavel C. H. M. , Underwood N. , Ragar S. R. 
Published: July 2010

AbstractThe theoretical basis for gamma densitometry of soil by transmission is reviewed. It is stressed that the familiar exponential‐inverse square law applies only to primary radiation. Data obtained with five different soils show such to be the case. Inclusion of secondary radiation in the measurement results in unwanted complications. The separation of the two types of radiation is achieved by scintillation counting and electronic discrimination.
Alfalfa Growth as Affected by Aeration and Soil Moisture Stress under Flood Irrigation
Authors: Kemper W. D. , Amemiya M. 
Published: July 2010

AbstractPeriodic lowering of oxygen content of the soil atmosphere to 13% or less for periods of 2 or 3 days appeared to have no adverse effects on alfalfa growth. If there were any adverse effects, they were entirely masked by the dominating effect of reduced soil moisture stress. When hydraulic moisture stress reached approximately 0.2 atm. at the 10‐inch depth, growth rate was greatly curtailed. When combined with the osmotic component of soil moisture stress, 0.2 atm. hydraulic stress resulted in total soil‐moisture stresses of about 1.9 and 2.8 atm. on leached and unleached plots, respectively.In one series of irrigations where 17 inches of water were applied, the soil surface was sealed against diffusion of oxygen for at least 8 days. During this time the average oxygen content in the root zone dropped to 6% with individual readings as low as 3%. Alfalfa on these plots grew much better than did alfalfa on adjacent plots which received normal irrigation.
Physical and Chemical Properties of Soil Aggregates in a Brunizem Soil
Authors: Wittmuss H. D. , Mazurak A. P. 
Published: July 2010

AbstractA surface sample of Sharpsburg silty clay loam was separated into aggregate fractions of diameters 4760 to 2380µ, 2380 to 1190µ, + … +, 37 to 18.5µ by means of rotary sieves and elutriators. A similar separation was made for primary particles. Each fraction of aggregates was analyzed for chemical and physical properties. The physical properties of aggregates were compared with those of primary particles.Data on water stability of aggregates show that as the diameter of aggregates decreased the stability increased. Particularly, aggregates of diameter 74 to 37µ and 37 to 18.5µ were different from the other fractions. Some of the differences in properties were: higher degree of aggregation, percentage of primary particles, available phosphorus, and exchangeable Ca++; lower moisture retention, percentage of organic matter, total nitrogen content, and exchangeable H+.At complete water saturation, aggregates and particles wetted under partial vacuum held greater amounts of water on a volume basis than did aggregates and particles wetted under atmospheric pressure. However, as tension was applied, more water was released from the aggregates and particles wetted under partial vacuum than under atmospheric pressure. At increased tensions, the differences between the two methods of wetting were less marked. At tensions of 0.33 atm. and higher, the moisture contents were nearly identical.Aggregates treated with VAMA soil additive, under both vacuum‐wetting and atmospheric‐wetting, released more water at successive tensions than did those without the additive.
Compression of Soil by Isotropic Stress
Authors: McMurdie John L. , Day Paul R. 
Published: July 2010

AbstractLoose packs of moist soil aggregates were encased in thin, cylindrical rubber membranes and subjected externally to air pressure in a triaxial test cell. The pressure was increased in increments, and the volume of the pack was determined from the axial strain after the rate of strain became less than 0.01% per minute at each step.The stress‐strain measurements revealed certain characteristics of the compaction process. The soil aggregates were deformed plastically during loading and had developed a condition of “plastic set” at the end of each step. However, the system expanded substantially when the pressure was released. This effect has been attributed to translocation of water within the aggregates as a result of differential stress. The mechanical behavior of moist soil aggregates is different in this respect from the behavior expected of perfectly plastic grains under the same conditions.A new sequence of plastic deformations occurred when the precompacted samples were recompressed to pressures which exceeded those previously applied. The volumetric contraction of the pack resulting from pressure gave an almost continuous envelope which represented successive states of plastic equilibrium throughout the pack.
Proportionate Uptake of Soil and Fertilizer Phosphorus by Plants as Affected by Nitrogen Fertilization: I. Growth Chamber Experiment
Authors: Grunes D. L. , Viets F. G. , Shih S. H. 
Published: July 2010

AbstractAn experiment was conducted to determine the effect of source and placement of nitrogen on the relative availability of fertilizer and soil phosphorus to plants. Barley was grown on seven soils in a controlled light‐temperature chamber. The addition of nitrogen fertilizer generally increased the percent of the total phosphorus absorbed by plants from bands of concentrated superphosphate. The addition of ammonium sulfate with the phosphorus band was generally more effective in increasing the percent of the total plant phosphorus derived from the fertilizer than was separating the nitrogen and phosphorus bands. Placement of sodium nitrate with, or on the opposite side of the plants from, the phosphorus band were approximately equally effective methods for increasing the percent of the total plant phosphorus absorbed from the fertilizer.Indications are that the effect of nitrogen, on increasing the relative uptake of banded fertilizer phosphorus, was associated with increased top and root growth, and also with decrease in soil pH.Detailed studies on one soil indicate that, when the phosphorus fertilizer was thoroughly mixed with the soil, the addition of nitrogen fertilizers did not increase the percent of the total phosphorus absorbed by plants from the fertilizer.
Desert Pavement and Vesicular Layer of Some Soils of the Desert of the Lahontan Basin, Nevada
Authors: Springer M. E. 
Published: July 2010

AbstractDesert pavement and vesicular layer are described as distinct horizons of some Gray Desert soils. Distribution of > 2‐mm. and < 2‐mm. particles in the profile along with laboratory tests suggest that accumulation of gravel and stones at the surface to form a desert pavement is not due solely to removal of finer material by wind or water. There has also been some upward movement of coarse fragments from the nearly stone‐free layers below.Some properties of vesicular layers are pointed out by field and laboratory studies. Natural vesicular structure was destroyed by sieving and a new, but similar, structure formed by merely wetting and drying the soil. This led to a hypothesis for origin of the vesicular layer as a pedogenic horizon.
The Use of Undisturbed Soil Cores to Investigate the Reclamation of Saline and Alkali Soils
Authors: Amemiya M. , Robinson C. W. 
Published: July 2010

AbstractField leaching investigations relative to the reclamation of saline and alkali soils generally require considerable land area, as well as time and personnel, for establishing and maintaining such studies. Concurrent with a field leaching experiment a laboratory leaching study was made to determine the relationship between results obtained from undisturbed cores in the laboratory and those obtained from field plots. Changes in infiltration rate, soluble salts, and exchangeable‐sodium‐percentage due to leaching, with and without gypsum, were compared.In view of the similarity of results obtained from undisturbed cores in the laboratory and field plots, it appears that soil cores, properly encased, can be used to predict with reasonable accuracy the reclaimability of saline and alkali soils. Although laboratory studies will not replace field investigations, cores could be used in making preliminary studies during period outside of the field season. The information thus obtained could then be used in the final selection of treatments to be considered in the field.