bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rice — Soil Conserving or Soil Depleting?
Authors: Green Victor E. 
Published: July 2010

AbstractA review of the literature shows that the soil‐rice plant‐water system of rice culture throughout the world has resulted in subsistence yields of rice grain for a period of 4,000 years. The system has also resulted in the maintenance of nitrogen and organic matter content of the soil, the prevention of soil erosion through the level terrace system of rice culture, the maintenance of soil structure even after purposeful puddling of the soil, the prevention of subsidence of organic soils, and a more rapid release of soil minerals.These beneficial effects are obtained only when the rice is grown on flooded soil. Dryland rice is comparable to the other small grains in their effects on the soil. Flooding unplanted soil has been shown to be deleterious to the nitrogen supply.In the Everglades region of Florida, flooded soils alternately planted to rice seem to be the only recourse to prevent a complete disappearance of the muck and peat by the year 2000.The Federal Government has not considered these factors in its various conservation programs to date.
Using Soil Survey Information for Farm Planning
Authors: Hockensmith R. D. 
Published: July 2010

AbstractDuring the first five months of 1952, the views of 79 farm‐planning technicians representing various sections of the country were obtained on the kind of information needed and the manner in which it could best be used in farm planning. Among the major preferences frequently expressed were: Maps of suitable scale, usually 8 inches to the mile for farms and 2 inches to the mile for range land (a 4‐inch field sheet enlarged to 8 inches is satisfactory for farms); precise information on the soil features significant in planning the farm; adequate interpretation in terms of suitability of land for cultivation, the practices and treatments needed, and potential responses to management; and specific information on such items as adapted crops, forage plants, or trees, suitability for irrigation or drainage, suitability for conservation structures, and susceptibility to erosion.Maps to meet these needs should show significant variation in internal soil features, slope, degree of erosion, and such factors as stoniness, salinity, overflow hazards, or any others that affect potential use of the land or the practices needed for its conservation and improvement. The farm‐planning technician wants specific information on these items, and accurate descriptions for his own use as he works with the farmer. The map that the farmer usually receives, however, shows not only these details, but a grouping of the closely similar mapping units into land‐capability units. The units are further grouped into subclasses and into the eight land‐capability classes. In some places the map received by the farmer shows land‐capability units but not the detailed mapping symbols.Technical guides for soil and water conservation planning are being organized by land‐capability units, which provide a convenient interpretation of the soil‐survey information. Part of the technical‐guide material for each unit is also prepared in form that is suitable for distribution to the farmer who has that unit on his farm. The land‐capability map of a farm and the appropriate guide sheets together make up a conservation guide for that farm. With the conservation guide as a foundation, and with job sheets for specific practices as the need arises, farmers are encouraged to work out basic conservation plans with their neighbors over a period of time that can vary from a few days to several years. The ideal is to guide them toward becoming conservation farmers who understand the particular capabilities and needs of their land and who apply and believe in the practices that will preserve their soils and keep them productive.
Float‐Valve Pressure Control for Porous‐Plate Apparatus
Authors: Hanks R. J. , Miller E. E. , Tanner C. B. 
Published: July 2010

AbstractA new type of pressure‐control regulator is described. The performance of this regulator is compared with the mercury tower regulator and with a two‐stage diaphragm regulator. The mercury tower and float‐valve regulators were both sufficiently precise for use with porous‐plate apparatus. The mercury tower was found to be quite inconvenient to use, requiring more experience than either of the other regulators. The float‐valve regulator was found to be easy to use with very little experience but was neither simple nor economical to construct. It was found that the two‐stage diaphragm regulator was not a precise pressure control below about 0.4 atni. However, because it is compact and inexpensive, the two‐stage diaphragm regulator appears to be quite useful where precision is not required.
Equipment for Subsampling and Packing Fragmented Soil Samples for Air and Water Permeability Tests
Authors: Reeve R. C. , Brooks R. H. 
Published: July 2010

AbstractThe permeability ratio, air to water, is used as a measure of the stability of soil structure. Equipment and procedures are described for subsampling, placement in containers, and packing fragmented soil samples for air and water permeability tests. Dropping the soil sample through a 4.75 mm. dia. round‐hole screen into the soil container was found to give a more uniform pack than four other packing methods tested. A reproducible degree of packing, as determined by air permeability determinations, was obtained by dropping the soil‐filled container repeatedly from a height of 2.5 cm. Intrinsic (air) permeability decreased rapidly with degree of soil packing and reached an approximately constant value at about 200 impacts. The relationship between air permeability and bulk density was found to be approximately linear for two soils tested.
The Nature of Phosphate Sorption by Calcium Carbonate
Authors: Cole C. V. , Olsen Sterling R. , Scott C. O. 
Published: July 2010

AbstractStudies on the nature of phosphate sorption by calcium carbonate indicate that when soluble phosphate fertilizers are added to calcareous soils, the reactions with calcium carbonate consist of rapid monolayer sorption on CaCO3 surfaces and, at high phosphate concentrations in the vicinity of fertilizer particles, the precipitation of dicalcium phosphate, or a compound with similar properties. The initial products of these reactions are characterized by very high specific surfaces and greater phosphorus solubility than the stable hydroxyapatite or fluorapatite. Dynamic equilibrium in calcareous soils involves all of these forms of phosphate. Some of the effects of the ionic environment on solubility of calcium phosphates were calculated and experimentally verified.
Influence of Fertilizers on the Crude Protein Yields of Bromegrass Pasture in the Matanuska Valley
Authors: Laughlin Winston M. 
Published: July 2010

AbstractCrude protein yields of bromegrass pasture were markedly increased by nitrogen fertilizers. This conclusion is based on field trials in the Matanuska Valley of Alaska during 1949, 1950, and 1951. A split‐plot factorial design was used to compare five rates of nitrogen fertilization, spring versus summer nitrogen applications, and three levels of phosphate‐and‐potash applied in a fixed ratio.Each increment of nitrogen, including the highest level (128 pounds of nitrogen per acre) produced highly significant increases in protein yields. Greatest production amounted to 636 pounds of crude protein per acre as compared to unfertilized plots which produced only 100 pounds. Sixfold increases were obtained from heavy fertilization which is economically feasible under present conditions.Significant nitrogen × phosphate‐potash interactions were observed. Early season protein yields are usually increased by phosphate‐potash applications while later clippings are generally not benefitted.Stage of maturity when grazed also determines crude protein yields which are the greatest during the early flowering stage.
Investigation of Small Grain Response to Various Applications of Nitrogen, Phosphorus, and Potassium on Several Kansas Soils
Authors: Gingrich J. R. , Smith F. W. 
Published: July 2010

AbstractFour wheat and three oat fertilizer experiments were established at various locations in the eastern half of Kansas for the crop year 1950–51. Objectives of these experiments were to obtain information (1) relative to the best time, rate, and method of applying nitrogenous fertilizers to wheat and oats, and (2) concerning the use of phosphorus and potassium in combination with various rates of nitrogen.Each experiment consisted of four factorially designed randomized blocks. Rates of nitrogen used were 0, 25, 50, and 100 pounds per acre; rates of available phosphoric acid were 0 and 50 pounds per acre; and rates of potash were 0 and 25 pounds per acre. Chemical analyses of the soils were made. Yield data were analyzed statistically and comparisons were made. Significant yield differences between treatments were obtained for each experiment.Greatest increases in yield of wheat accompanied the heaviest applications of nitrogen with the single exception of one location which recently had been in alfalfa. The application of both phosphorus and potassium increased the yield of wheat appreciably at this location, most of the increase being due to phosphorus. The application of potash increased the yield appreciably where no ammonium nitrate was supplied.Significant increases in yield of oats were obtained at each location following the application of 50 pounds per acre of nitrogen. The inclusion of phosphorus and potassium in the fertilizer did not affect oat yields very much.The time of application of nitrogen generally had little influence on yields of either wheat or oats. From an economical standpoint, application of all the nitrogen at seeding time might be preferable.
The Influence of Soil Aggregate Stabilizers on the Biological Activity of Soils
Authors: Fuller W. H. , Gairaud Catherine 
Published: July 2010

AbstractThe influence of three synthetic polyelectrolytes, hydrolyzed polyacrylonitrile (HPAN), modified vinyl acetate maleic acid compound (VAMA), and a new polymer 212 on the biological activity in six agricultural Arizona soils and quartz sand was investigated. Particular attention was directed to (a) the rate and extent that these materials decompose, (b) the possible toxic or inhibitory effect that these materials may exert on the soil microflora, and (c) the effect that these materials have on the rate and extent of decomposition of a crop residue such as oat straw.VAMA was found to stimulate biological activity in soil as evidenced by the total cumulative CO2 evolved during 14 days of incubation with soil. HPAN and polymer 212 had little effect on the over‐all biological activity of well‐aerated soil cultures during this period of incubation. This situation appeared to be the same regardless of the presence or absence of oat straw.The rate of evolution of CO2 measured during intervals of 24 hours, indicated that in soil (a) a certain small portion of VAMA and a very small portion of HPAN and polymer 212 is immediately available to attack by the soil microflora, and (b) when this supply is exhausted the remaining material is so slowly available it has no measurable influence on the cumulative CO2 evolved over a period of five months by the method employed.The presence of VAMA in sand delayed peak CO2‐evolution depending on the rate of application. This indicated that the soil conditioner had a temporary toxic or inhibitory effect on the microflora in the sand cultures.
The Influence of Certain Fertilizing Materials on the Soil Reaction and Nutrient Level in the Potato Row during the Growing Season
Authors: Dunton E. M. , Hall R. B. , Taylor M. E. 
Published: July 2010

AbstractThis is a continuation of an experiment conducted at the Virginia Truck Experiment Station in 19483 to determine the influence of acid and neutral fertilizers on the soil reaction in the potato row during the growing season. Results from the 1948 study indicate that fertilizers applied in bands in the potato row had a marked influence on lowering the soil reaction, and that the degree of this influence was dependent upon where the sample was taken with respect to the fertilizer bands. The purpose of this study was to determine whether fertilizer materials might differ in their influence on the soil reaction, with some possibly being more effective than others in reducing the pH of soils where there was danger of scab.A commercial 5‐10‐5 fertilizer was used for treatment 1, and hand mixed materials were used for the other five treatments. In treatment 2, all the nitrogen was derived from NH4NO3, while in treatment 3, it was derived from (NH4)2SO4. In treatments 4 and 5 the nitrogen was derived from NH4NO3, and 50 and 100 pounds of sulfur, respectively, were added per ton of fertilizer. All of the treatments were applied at the rate of 2,000 pounds per acre except treatment 6 where the fertilizer mixture was applied at the rate of 3,000 pounds per acre.Soil samples were taken 2, 4, 8, and 12 weeks after planting at certain locations around the band. Phosphorus, potassium, pH, nitrate and conductivity tests were run on all samples.The six fertilizer mixtures markedly lowered the soil reaction in the potato row during the 1949 and 1950 growing seasons. This influence varied with the sampling location or position of the soil sample with respect to the fertilizer bands, with the greatest influence being exerted above the bands. The lowering of the pH was associated with increases in salt concentration in nitrates and in potassium. There was no important differences in the influence of the six different mixtures on the soil acidity except where the soil samples were taken from the fertilizer bands.
The Effects of Different Rates, Times, and Methods of Application of Various Fertilizer Combinations on the Yield and Quality of Hard Red Winter Wheat, 1949–50
Authors: Williams B. C. , Smith F. W. 
Published: July 2010

AbstractA study was made to determine the effect of nitrogen fertilizer, alone and in combination with phosphate and potash fertilizers, on the yield and quality of wheat; to determine the effect of nitrogen carrier on wheat yield and quality; and to determine the effect of time and method of application of nitrogen fertilizer on yield and quality of wheat.Yields of wheat were found to be increased at all locations by the use of nitrogen fertilizers. Increasing the rate of nitrogen applied gave varied but similar results. Increases in yields were noted for inclusion of phosphatic fertilizer in the treatment while the inclusion of potash fertilizer had no effect, beneficial or detrimental, on yields of wheat. The later applications of nitrogen fertilizer gave more increase in yield of wheat than did nitrogen fertilizer broadcast before seeding. Only at Manhattan was NH4NO3 significantly superior to CaCN2 in increasing the yields of wheat. At other locations, no differences in effect of type of carrier of nitrogen on yields of wheat were observed.Test weights of wheat were affected by several treatments at Manhattan and Belleville but not at the other two locations. At Belleville, the resulting effect was a reduction of test weight of the treated plot yield below that of the untreated plot yield, but the effect at Manhattan was in general a reversal of that found at Belleville.Protein content was increased by several treatments as a result of the use of nitrogen fertilizer alone or in combination with phosphate and/or potash fertilizers. This tendency was most pronounced for the heavier applications of nitrogen fertilizer. The inclusion of potash in the treatment caused an increase in percentage of protein at Belleville but at other locations had no effect on percentage of protein. Phosphorus when included in the treatment decreased the protein percentage. The type of nitrogen carrier had little effect on protein percentage contained in wheat.
Changes in Composition of Irrigated Soils as Related to the Quality of Irrigation Waters
Authors: Thorne D. W. , Thorne J. P. 
Published: July 2010

AbstractThese studies were conducted to determine the effects of field application of waters of different quality on the chemical composition of soils. Soil samples were obtained from paired sites within irrigated and unirrigated soil areas located in 14 different soil locations and representing use of 12 different irrigation waters. The data for irrigation water and soil composition were statistically analyzed for regression and correlation relationships.The salt content of the soils was found to be closely related to the salt content of the irrigation waters.The percentages of exchangeable sodium in the soils had significant regressions on sodium percentages, weighted sodium percentages, sodium adsorption ratios and the theoretical equilibrium exchangeable sodium percentages for the irrigation waters included in the study. The regressions of exchangeable sodium percentages on excess sodium percentages of the waters were not significant.There were significant negative regressions between increase in lime content of the irrigated soils (calcium carbonate content of irrigated soil minus calcium carbonate content of non‐irrigated soil) and the electrical conductance, the chloride content, calcium and magnesium content and sulfate content of the irrigation water. Lime tended to be leached out of soils when the electrical conductance of the irrigation waters exceeded 2 millimhos per cm. and frequently to increase in soils irrigated with waters of lesser salt content.The data do not indicate that the carbonates and bicarbonates in irrigation waters studied contributed significantly to either the accumulation of carbonates in soils or to increase in exchangeable sodium percentages.
Chemical and Mineralogical Properties of a Brown Podzolic Soil
Authors: Tamura Tsuneo , Swanson C. L. W. 
Published: July 2010

AbstractChemical and mineralogical studies were made of the Wethersfield silt loam, a Brown Podzolic soil derived principally from sandstone, siltstone and shale. The clay minerals identified were illite, vermiculite, chlorite, and interstratified montmorillonitechlorite. Illite decreased from the parent material (70%) to the surface (35%) while vermiculite increased from 5% in the parent material to 40% in the surface. The interstratified montmorillonite‐chlorite was positively identified in the B3 and C horizons and composed 15% of the clay fraction. The chlorite, hematite, quartz and feldspars were present in quantities ranging from 5–10% each. Field observations of a compact C horizon capable of supporting a perched water table and a 7% slope facilitating lateral movement of water help to explain the results of the mechanical, chemical, and mineralogical analyses performed in the laboratory.
Properties of the Galva and Moody Series of Northwestern Iowa
Authors: Foth H. D. , Riecken F. F. 
Published: July 2010

AbstractThe purpose of this investigation was to study soil development in relation to loess thickness and annual precipitation in northwestern Iowa. From a study of six profiles located along two traverses, it was concluded that soil properties were related to both loess thickness and annual precipitation on the basis of the amount and distribution of clay, percentage of total nitrogen, base saturation and depth to secondary lime.
The Influence of Soil Properties on the Effectiveness of Synthetic Soil Conditioners
Authors: Laws W. Derby 
Published: July 2010

AbstractThe influence of soil organic matter, soil acidity, free calcium carbonate, soil texture, type of clay mineral, and destruction and re‐forming of stabilized aggregates on the effectiveness of the soil conditioners was studied. Wet‐sieve aggregation data were expressed as mean weight‐diameter and the effectiveness of the conditioner was obtained by subtracting the mean weight‐diameter of the untreated soil from that of the treated soil.Oxidation of the soil organic matter greatly decreased the effectiveness of the soil conditioner. Adjusting acid soils to pH 6.3 to 7.0 with calcium carbonate increased the effectiveness of the soil conditioner, but the presence of free calcium carbonate in the soil appears to inhibit the effectiveness.In synthetic soils the effectiveness of the conditioner reached a maximum at 15% clay where acid Cecil clay colloid was used. When base saturated colloids were used, the maximum effectiveness of the conditioner occurred at about 10% clay content. When applied to Texas soils, the conditioner was more effective as an aggregating agent on sandy loam and clay loam soils than on heavy clay soils.
The Effect of Sodium Carboxymethylcellulose on Some Physical Properties of Ohio Soils
Authors: Taylor George S. , Baldridge Paul E. 
Published: July 2010

AbstractThe effect of sodium carboxymethycelluloses (CMC) on soil aggregation, plasticity, moisture equivalent, fifteen‐atmosphere‐percentage, and water permeability was investigated in the laboratory. These compounds contained different degrees of substitution of sodium carboxymethyl groups, ranging from 0.32 to 1.28 substitutions per anhydroglucose unit. In general, increasing the degree of substitution resulted in greater soil aggregation, increased water permeability and larger plastic limits. Varying rates of CMC up to 0.5% concentration also resulted in significant increases in these soil characteristics. None of the compounds had any effect on the moisture equivalent and fifteen‐atmosphere‐percentage. The duration of aggregates stabilized by the 0.70 substitution was found to be much less than those aggregates stabilized by the higher‐substituted types.
Effect of Several Insecticides on Ammonification and Nitrification in Two Neutral Alluvial Soils
Authors: Brown A. L. 
Published: July 2010

AbstractColumbia fine sandy loam and Yolo loam were incubated in the laboratory at 15% moisture and five rates (0, 0.0005%, 0.005%, 0.05%, and 0.5% active ingredient) of insecticide. The insecticides used were, DDT, aldrin, dieldrin, lindane, heptachlor, and chlordane. All insecticides were applied as wettable powder formulations. Ammonia and nitrate were determined after 15, 30, and 60 days of incubation.In general, the results seem to indicate that rates of insecticide of 0.05% or greater will inhibit nitrification in some soils. DDT is the least toxic to the nitrifiers of the insecticides studied, while aldrin, dieldrin, and chlordane are the most toxic. Lindane and heptachlor occupy an intermediate toxicity. The significance of the results is discussed.The rates of insecticide required to produce an effect on nitrification and ammonification are greatly in excess of common rates of application for the materials studied.