bluuebunny/crossref_metadata_2025_split huggingface dataset:
Movement of Ammonium Nitrogen in Soils
Authors: Ray H. E. , MacGregor J. M. , Schmidt E. L. 
Published: July 2010

AbstractThe distribution of applied ammonium nitrogen in four southern Minnesota soils maintained at constant moisture tension and nitrogen concentration was determined in the laboratory. Ammonium nitrate enriched with N15 in the ammonium ion was used as a source of nitrogen. The soils varied in texture from loamy fine sand to loam, and in exchange capacity from 3.2 to 34.2 me. per 100 g.Movement of ammonium nitrogen in Anoka loamy fine sand was predominantly downward and lateral. In contrast, movement of ammonium nitrogen in Nicollet loam was nearly symmetrical with slightly greater upward and lateral movement than downward movement. Retention of applied ammonium nitrogen in the zone of injection amounted to 2.0 me. per 100 g. of soil in Anoka loamy fine sand, and to 14.4 me. per 100 g. in Nicollet loam. Movement and retention of ammonium nitrogen were intermediate in the Fayette silt loam and the Barnes loam.
The Effect of Longtime Use of Winter Cover Crops on Certain Physical Properties of Commerce Loam
Authors: Patrick W. H. , Haddon C. B. , Hendrix J. A. 
Published: July 2010

AbstractA study has been made of certain physical properties of Commerce loam as affected by longtime use of winter cover crops preceding cotton. The treatments used were: (1) no treatment, (2) 40 pounds per acre of inorganic nitrogen, (3) common vetch, and (4) hairy vetch. The individual plots were sampled in 1955 and analyses made of the following soil properties: organic matter, total nitrogen, aggregation index, bulk density, noncapillary porosity, water permeability, field capacity, and wilting point.The organic matter and total nitrogen contents were highest in the hairy vetch plots and lowest in the plots receiving 40 pounds per acre of nitrogen and in the untreated plots. The values for aggregation, bulk density, and noncapillary porosity showed that the physical condition of the soil was best in the hairy vetch plots, next best in the common vetch plots, and poorest in the untreated plots and the plots receiving 40 pounds per acre of nitrogen. The 25‐year average per acre yield of cotton from the different treatments was: hairy vetch, 2,000 pounds; common vetch, 1,680 pounds; 40 pounds of nitrogen, 1,470 pounds; and no treatment, 900 pounds. The ability of the 40 pounds of nitrogen to produce an increase in yield over the untreated plots was not reflected in an increased organic matter content or an improved soil physical condition.
The Effect of pH on the Uptake of Radioactive Isotopes from Solution by a Soil
Authors: Rhodes D. W. 
Published: July 2010

AbstractThe reactions with natural earth materials of fission products and plutonium are of current interest in the field of atomic energy waste disposal and soil chemistry.Solutions containing less than 1 × 10‐9 moles per liter of selected radioisotopes were equilibrated with samples of a calcareous subsoil. The uptake of these radioactive isotopes by the soil was measured as a function of pH. The uptake of Cs137 was not affected appreciably by varying the pH between 4 and 10. The maximum uptake of Sr90 occurred at about pH 10 and decreased rapidly as the pH was lowered. The radioisotopes Pu239, Ce144, Zr95, ‐Nb95, Y91, and Ru106 exhibited a maximum uptake between approximately pH 4 and pH 8. Above pH 8 a region of reduced uptake occurred and persisted up to at least pH 11 for most of the polyvalent radioisotopes.The addition of high concentrations of sodium salts to the solution inhibited the uptake of both Cs137 and Sr90 by soil. A relatively small concentration of phosphate (0.01 M) added to the system was found, in effect, to nullify the interference of sodium ion with the uptake of Sr90, but the phosphate ions had no apparent influence on the uptake of Cs137.
Nitrogen Loss in Gaseous Form from Soils as Influenced by Fertilizers and Management
Authors: Loewenstein H. , Engelbert L. E. , Attoe O. J. , Allen O. N. 
Published: July 2010

AbstractThe experiments reported here were aimed to ascertain the magnitude of gaseous loss of nitrogen in Spencer silt loam under greenhouse conditions, as affected by pH, form of nitrogenous fertilizer, energy material, and cropping. Four additions of 150 ppm. nitrogen each were made to both cropped and uncropped soils; four successive oat crops were grown on the former.At field moisture levels large volatile losses of nitrogen occurred from the uncropped soil regardless of treatment. Over an 11‐month period these losses ranged from 35% in the soil at pH 5.5 amended with straw and nitrogen as (NH4)2SO4 to 72% in the soil at pH 6.5 with (NH4)2SO4 but no straw. In soils similarly treated and subsequently cropped with oats, the losses were between 7 to 8%.In other experiments the levels of NO3, NH4, and total N in the uncropped Spencer silt loam at pH 6.5 were measured 8 times during a 1‐year period. Irrespective of the form of nitrogen added, presence or absence of straw, and whether liming occurred at the time of fertilization or 12 weeks earlier, the greatest decrease in total nitrogen occurred during the first 6 weeks after fertilization and thereafter remained more or less constant over the year. Approximately one‐half of the 300 ppm. nitrogen added was volatilized from the soil under each treatment. Concurrent increases in nitrate nitrogen levels occurred without exception.
Chemical and Physicochemical Properties of Soil Humic Colloids: III. Extraction of Organic Matter from Soils
Authors: Choudhri M. B. , Stevenson F. J. 
Published: July 2010

AbstractA study was made of the effects of certain soil treatments on the amounts of humic acids and organic matter extracted by a number of reagents, including sodium pyrophosphate of different pH values, and alkali. The pretreatments were: (1) removal of carbonates and exchangeable bases, (2) removal of free iron and aluminum oxides by mild reducing reagents, and (3) removal of silicate minerals with hydrofluoric acid. The extraction of organic nitrogen was taken as an index of organic matter extracted.Removal of calcium and free iron and aluminum oxides increased the solubility of organic matter in alkali but had no effect on extraction by pyrophosphate. The removal of silicate minerals by repeated treatment of the soil with hydrofluoric acid was particularly effective in facilitating the extraction of humic acids by pyrophosphate. The proportion of humic acid nitrogen extracted to total organic nitrogen extracted was considerably higher in pyrophosphate extracts than in extracts of other reagents.Several organic‐complexing reagents, including cupferron, 8‐hydroxyquinoline, acetylacetone, and disodium dihydrogen ethylenediamino tetraacetate, were also tested and it was found that they were not as effective as neutral sodium pyrophosphate for removing soil organic matter. In addition, a procedure was proposed for mitigating autoxidation reactions during extraction of organic matter.
Sols Bruns Acides of the Northeastern United States
Authors: Baur A. J. , Lyford W. H. 
Published: July 2010

AbstractSols Bruns Acides is the name now used in Belgium, France, and possibly other European countries for a class of soils at the great soil group level. Similar soils have developed under forest vegetation in the Northeastern United States, and it is proposed that the same name be applied here. In the past these soils have been included with Brown Podzolic, weak Podzol, weak Gray‐Brown Podzolic or Red‐Yellow Podzolic soil groups. Morphologically, Sols Bruns Acides have a thin A1 horizon; a paler A2 or A2‐like horizon (possibly a B1 horizon) which is poorly differentiated from the B2 horizon; a B2 horizon with uniform color from top to bottom, weak subangular blocky structure, and silicate clay accumulation not evident or appearing only in traces. Sola of these soils are strongly to very strongly acid and have low base status. Distinction between Sols Bruns Acides and the Gray‐Brown Podzolic and Red‐Yellow Podzolic soils rests mainly on amounts of clay accumulation in the B horizon. Sols Bruns Acides differ from weak Podzols and Brown Podzolic soils mainly in color and structure of the B horizon. The latter have in the upper B horizon strong colors which fade with depth and weak, fine granular structure.
Characteristics of Eolian Influenced Soils in Connecticut: II. Chemical and Mineralogical Properties as Keys to Profile Mixing
Authors: Tamura Tsuneo , Ritchie A. , Swanson C. L. W. , Hanna R. M. 
Published: July 2010

AbstractUnderlying a small eolian soil deposit east of the Connecticut River, Triassic till and stratified sand and gravels had large particles, low free iron oxide content, red hue, and montmorin. The wind‐blown soil near the source had small particles, high free iron oxide content, brown color, and no montmorin. In the thinner soil mantle at a distance from the source larger particles appeared; the free iron oxide content decreased; the soil became redder; and montmorin appeared. All of these facts indicate that the distant profiles were mixed. An index of mixing based on mean size was defined using 0 for eolian sediment and 100 for the underlying deposit. The index was as great as 75 in the B and 50 in the A horizons. The presence of unstable montmorin and the scarcity of free iron oxide in the mixed profiles indicate that the mixing phenomenon was post glacial, relatively recent, and likely due to tree throw. From data on the Connecticut, Illinois and New Jersey deposits a prediction was made concerning the change in particle size with distance in any deposit.
Characteristics of Water Removal in a Tile‐Drained Humic‐Gley Soil
Authors: Taylor George S. , Goins Truman 
Published: July 2010

AbstractA water table was established within a few inches of the ground surface on a tile‐drained Humic‐Gley soil, after which measurements of water‐table levels and soil moisture contents were made at various time intervals. The hydraulic conductivity of the A horizon (0 to 8 inches) was considerably greater than that of the B horizon (8 to 50 inches), as shown by auger‐hole permeability measurements. The drains were located in the B horizon at an average depth of 30 inches and with a lateral spacing of 40 feet.During drawdown, the water‐table surfaces were nearly horizontal except in the region near the drains. When the water table receded from the ground surface to drain depth, approximately 0.50 inches of water were removed from the A horizon; whereas, only 0.10 inches were removed from the upper 22 inches of the B. An analysis of the drawdown and water‐removal characteristics indicated that the drains brought about rapid drainage in the A horizon but that deep seepage may account for significant water removal from the B. Although the A horizon was more than 50 times as permeable as the B, the A horizon was too shallow to permit significant water removal by lateral flow to the backfill.
Extraction of Potassium from Soils by Sulfuric Acid
Authors: Hunter A. H. , Pratt P. F. 
Published: July 2010

AbstractMethods of extracting potassium from soils by use of sulfuric acid have been developed. The amounts of K extracted from several Ohio and New York soils by these methods were compared with those extracted by neutral 1N NH4OAc and boiling 1N HNO3 methods as means of furnishing a reliable index to the “plant‐available” K of soils.Using H2SO4 method 1, amounts of K were extracted which were highly correlated with amounts of K extracted from soils by cropping. The correlation coefficient thus obtained was significantly different at the 1% level from the coefficients obtained by using ammonium acetate or boiling nitric acid.The sulfuric acid methods developed are simple to use and, since an exact quantity of heat energy is furnished to the soil extraction system, these methods theoretically furnish a means of releasing a constant amount of non‐exchangeable K, due to breakdown of primary and secondary minerals, as well as the exchangeable K from a particular soil.
Identification of Clay Minerals in the Surface Horizons of Four Kentucky Soils
Authors: Dixon J. B. , Seay W. A. 
Published: July 2010

AbstractKentucky is a transitional area between two great soil groups, the Gray‐Brown Podzolic and the Red‐Yellow Podzolic. The surface horizons of four soils representing the two great soil groups and one transitional soil were studied. The soils were: Cookeville (Red‐Yellow Podzolic), Loradale (Gray‐Brown Podzolic), Armour (Gray‐Brown Podzolic), and Pembroke (Red‐Yellow Podzolic—Gray‐Brown Podzolic transitional). Mechanical analyses showed that three of the four soils were silt loams, while Loradale was a silty clay loam. Mineralogical studies made of the clay fractions of these soils using X‐ray diffraction spectrometer and differential thermal analysis methods showed that chlorite, quartz, and kaolinite were prominent minerals in the clay fraction of the Cookeville soil. Kaolinite, illite, quartz and an interstratified mixture were the prominent components in the clay fractions of the other three soils.
Studies on Nitrogen Tie‐Up as Influenced by Location of Plant Residues in Soils
Authors: Parker D. T. , Larson W. E. , Bartholomew W. V. 
Published: July 2010

AbstractIn field experiments it has been observed that nitrogen availability to corn is frequently depressed where crop residues low in nitrogen remain on the soil surface as compared to where the residues are incorporated in the soil. The purpose of this investigation was to evaluate the immobilization of soil nitrogen as influenced by position of crop residue with reference to the soil.In greenhouse experiments nitrogen uptake by Sudangrass was significantly greater when cornstalk residue was applied to the soil surface than when it was incorporated in the soil. By comparison with a treatment receiving no residue it was concluded that considerable nitrogen was immobilized by cornstalk residue incorporated in the soil, whereas no immobilization occurred with cornstalk residue on the soil surface.On the other hand, in laboratory experiments it was demonstrated that soil nitrogen could be moved to and immobilized in low‐nitrogen residue on the soil surface and that the movement of nitrogen into surface residue was enhanced in treatments which were subsurface irrigated and in treatments held at a low‐air humidity. Also it was found in laboratory experiments that subsurface residue decomposed more rapidly than did surface residue and that this more rapid decomposition resulted in an increase in percent nitrogen but in a decrease in total nitrogen of the residue. Likewise, percent nitrogen of surface residue increased, but total nitrogen increased or decreased, depending upon the conditions of the experiment.The results of a field experiment demonstrated that surface applications of low‐nitrogen residue without added nitrogen fertilizer resulted in decreased nitrogen uptake by corn and yield of corn. However, when nitrogen fertilizer was added along with the residue, yields were increased above the unmulched check.
The Correlation of Soil Phosphorus with the Yields of Ladino Clover
Authors: Welch L. F. , Ensminger L. E. , Wilson C. M. 
Published: July 2010

AbstractLadino clover (Trifolium repens) was grown in 11‐ by 6‐foot concrete‐walled field bins that contained three soil types representing large acreages in Alabama, namely Norfolk sandy loam, Eutaw clay, and Cecil clay. Soil samples were taken from the bins prior to seeding the clover and were extracted for soluble phosphorus by three extracting solutions. The solutions used were 0.05N HCl + 0.025N H2SO4, 0.5M NaHCO3, and 0.03N NH4F + 0.1N HCl. The procedure used with each solution can readily be adapted for rapid, relatively inexpensive tests as is required of a method to be used in a soil testing laboratory. The study consisted of 40 bins of each soil type, and because of past phosphorus treatments within a soil type, the bins differed greatly with respect to the amounts of soluble phosphorus present.Six harvests were taken from the bins, three each in 1954 and 1955. The following correlations were made: relative yields for 1954 with soil test P2O5 values as determined by each solution on each soil type, relative yields for 1955 with soil test P2O5 values, and P2O5 values for one solution with values for another solution on a given soil type. All correlation coefficients were highly significant. Regressions equations were calculated for the regression of soil test P2O5 values on 1954 relative yield, 1955 relative yield, and total relative yield. Classes of soil test P2O5 values were calculated from the regression equations on the basis of the amount of P2O5, as indicated by soil tests, required to give a specified relative yield.Data presented show that either of the three soil testing methods can be used satisfactorily as a basis for making phosphorus recommendations for the soils and crop studied. No one solution proved to be statistically better than the other two. All solutions tended to give higher correlation coefficients for the Eutaw and Cecil soils rather than for the Norfolk.
Calcium Phosphate Fertilizers: II. A Petrographic Study of Their Alteration in Soils
Authors: Lehr J. R. , Brown W. E. 
Published: July 2010

AbstractAs a supplemental study to pot‐culture tests in which six calcium phosphates were investigated, petrographic examinations were made of the fertilizer residues and surrounding soils. The materials tested were Ca(H2PO4)2 · H2O, CaHPO4 · 2H2O, CaHPO4, Ca4H(PO4)3 · 3H2O, Ca3(PO4)2, and Ca10(PO4)6(OH)2).The purpose was to determine the physical and chemical alterations that the materials had undergone while in a soil environment and in the presence of feeding roots. Correlations between these observations and plant response were sought.Some correlation was found between plant response and; (a) relative rates of solution or solubilities of the phosphates, and (b) chemical alterations of the phosphates. Positive evidence was found for 4 hydrolysis reactions, 2 of which confirm the postulated formation of octocalcium phosphate and apatite. Other observations lend new support to the concept of contact feeding by plant roots.
The Importance of Subsoil Phosphorus to Corn
Authors: Murdock John T. , Engelbert L. E. 
Published: July 2010

AbstractIn order to determine the depth to which the corn plant feeds, field studies were conducted to measure the recovery of P32 from successive 6‐inch soil horizons. The available soil phosphorus in these horizons was determined by the Truog, Olsen, and Bray No. 2 tests. The accuracy of these tests was checked by correlations with A values and phosphorus uptake data obtained from greenhouse studies.Corn recovered more fertilizer phosphorus from the 6‐ to 12‐inch horizon of 2 of the 4 soils studied than from the plow layer and in the other soils recovery was almost as great as from the plow layer. Recovery from any layer below the 12‐inch depth was considerably less than from the top 2 layers, but the combined recovery from these lower layers was appreciable. This indicates that a large percentage of the phosphorus in the corn plant may come from the subsoil if the subsoil is fairly well supplied with available phosphorus. In most cases, the available phosphorus in the plow layer of the soils studied was greater than that in any of the respective subsoil horizons. However, it was much less than the combined amount found in all of the subsoil penetrated by corn roots.According to the greenhouse studies the three phosphorus tests used gave an accurate measure of the available phosphorus in the subsoils as well as that in the plow layer.
Soil Compaction Zones as Affected by Conservation Cropping Systems
Authors: Elder William R. 
Published: July 2010

AbstractThe effects of soil compaction on rooting depth, aeration, and effects on erosion and drainage of Houston Black clay, a monotextured Grumusol are reported.Field samples were taken over a broad area representative of definite nonconservation and conservation cropping systems. A single field was sampled on a sequence basis to measure the changes wrought by tillage from a perennial grass to a mature cotton crop.Compaction zones were measured by the change in bulk density and structural index as compared to normal values for virgin soils or soils in good condition. Bulk densities and structural indices were determined by the use of a nonpolar liquid.Compaction zones were common under continuous row crop systems.Compaction zones form rapidly as a result of poor soil management, even within a single cropping season following a 2‐year period of perennial grass.
Transformations and Movement of Urea in Soils
Authors: Broadbent F. E. , Hill G. N. , Tyler K. B. 
Published: July 2010

AbstractSamples of several California soils were incubated in a controlled environment chamber after addition of varying amounts of urea in solution. Samples were analyzed after time intervals ranging from 1 day to 8 weeks. In short‐term experiments analyses for residual urea were performed at frequent, short intervals, and in longer‐term experiments nitrification of the hydrolysis product was followed. At 45°F., 200‐ and 400‐ppm. amounts of urea were completely hydrolyzed after 7 days, although some urea remained after 3 days. At 75°F., no urea remained after 2 days when the initial application was 400 ppm or less. At 800 ppm., considerable urea remained at 3 days but none at 14 days.Urea was rapidly nitrified in all soils at moderate levels of application but was inhibited in the poorly buffered Hanford sandy loam by the 800‐ppm. application, due to the high pH produced.Leaching experiments with soil columns showed that urea moves less rapidly than nitrate, partly because of rapidly hydrolysis to ammonia and partly because urea itself is held by weak absorption forces.
Restoration of Soil Structure with Redtop and Other Sod Crops
Authors: Wisniewski Adam J. , Salomon Milton , Smith John B. 
Published: July 2010

AbstractWater‐stable aggregates, soil organic matter, bulk densities, and soil moisture retention at 50‐cm. tension were determined for a Bridgehampton silt loam following various treatments involving sod crops in rotation with potatoes and continous potatoes.An overall positive correlation was found between organic matter and aggregation. Although plots that were in a redtop‐potato rotation were significantly better aggregated than those in a red clover‐potato rotation and plots in continous potatoes, increased aggregation was not always accompanied by an increase in total soil organic matter. This implied that the type of soil organic matter resulting from the decomposition of redtop is more effective in promoting water‐stable aggregates than either the native organic matter or that resulting from the decomposition of other plant residues studied. Potato yields appear to be more a function of aggregation than of total soil organic matter. Some evidence exists that the decomposition of native organic matter has been hastened by the addition of redtop residues. A microscopic examination of aggregates > 5 mm. shows that roots are partly responsible for binding some of the smaller aggregates into larger ones.
Soil Nitrogen Accumulation Under Black Locust
Authors: Ike A. F. , Stone E. L. 
Published: July 2010

AbstractSoil nitrogen accumulation beneath stands of black locust, a leguminous tree, was studied at four locations in Tompkins County, N. Y. Adjacent areas identical in prior treatment served as controls. Significant increases were found under three 16‐ to 20‐year‐old plantations but not under a 5‐ to 10‐year stand. These changes extended below the 0‐ to 7‐inch depth, with total nitrogen increases of approximately 600 pounds per acre in the 0‐ to 20‐inch layer.In a greenhouse study of availability, Sudangrass cultures were able to absorb somewhat larger amounts of nitrogen from soils under locust. Measurement of nitrogen in ground vegetation and estimates of return by locust foliage indicate an annual turnover in excess of 50 pounds per acre.