bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction Effects of Boron and Lime on Barley
Authors: Gupta Umesh C. 
Published: July 2010

AbstractA greenhouse study involving six levels of B and four levels of lime was conducted on barley (Hordeum distichon L., cultivar ‘Herta’). Boron toxicity symptoms occurred at 0.5 to 4.0 ppm applied B, with the most severe symptoms occurring at 4.0 ppm B level at soil pH 5.3. At 0.5 ppm B, no visible symptoms occurred at pH values of 6.3 and 6.8, and at 1.0 ppm B no symptoms occurred at pH 6.8. There was a highly significant soil pH × B interaction, in which high rates of B were more detrimental to kernel yields at lower pH than at high pH values. The highest kernel yields were recorded with 0.25 ppm B at soil pH 5.8. An application of 4.0 ppm B at soil pH 5.3 and 5.8 did not produce any kernels.The B concentrations of boot stage tissue (b.s.t.) and straw showed a B × pH interaction resulting in decreased B with increasing rates of lime. The lowest concentrations of 1.9 to 5.1 ppm B were found in the B1 treatments. A B concentration of about 12 ppm in the b.s.t. and of 7 ppm in straw at soil pH 5.8 appeared to be related to maximum yields. Boron deficiency was related to B concentrations of about 2 to 5 ppm and Ca/B ratios of about 540 and higher in the b.s.t. A Ca/B ratio of about 180 appeared to be optimum, while ratios of 10 to 45 were in the severe B toxicity range. The Ca/B ratios of > 697 in straw were associated with B deficiency. A Ca/B ratio of 260 appeared to be sufficient and ratios of 7 to 22 were related to severe B toxicity.A range in the B concentration of 1.4 to 9.9 ppm and in Ca/B ratio of 343 to 1,159 in the b.s.t. collected from Prince Edward Island fields indicated a deficiency of B in many soils for growing barley. However, no visible B deficiency symptoms were found either under greenhouse or field conditions.
White Phosphorus as a Phosphatic Fertilizer
Authors: Rodriguez Armando , Bohn Hinrich L. , Johnson Gordon V. 
Published: July 2010

AbstractWhite P, in amounts equivalent to phosphate fertilization rates, oxidized within 2 days in soils. Sorghum (Sorghum vulgare Pers.) and tomatoes (Lycopersicon esculentum Mill.) responded equally to white P and NH4H2PO4 in greenhouse tests of neutral and calcareous soils. In an acid soil, the growth rate was delayed initially in the white P treatments compared to phosphate. Later growth narrowed the gap between the phosphatic sources. After liming the acid soil, the growth delay was absent and the yields from white P treatments were as great as from NH4H2PO4. No evidence of phytotoxicity was found in these experiments.
Fractional Water‐Sediment Sampler
Authors: Heinemann William H. , Brown Melvin J. 
Published: July 2010

AbstractThe fractional water‐sediment sampler enables collecting large‐volume representative samples of water and sediment from surface drainage streams. Free fall‐flow, such as obtained at drop structures, is required for the operation of the sampler. The total sediment‐laden water flow sampled can be split to 50 or 25% of the original sampled flow before being directed to containers by adding one or two splitting stages.
Relative Flow Rates of Salt and Water in Soil
Authors: Krupp H. K. , Biggar J. W. , Nielsen D. R. 
Published: July 2010

AbstractA hydrodynamic equation for the mixing of two miscible solutions in a porous media has been combined with the Gouy theory for ion distribution in soil pores in order to examine the effect of flow velocity and ion distribution in the pores on the breakthrough curves. The model considers zones of mobile and immobile solution in the porous media, and the extent these zones are affected by the total concentration of the solution and the pore water velocity.Miscible displacement experiments of 36Cl and 3H through Panoche clay loam at 0.1, 0.01, and 0.001N total salt concentration using CaCl2 were performed on the same column at a fast and slow flow velocity. It was shown that the exclusion volume for isotope and the separation volume for 36Cl and 3H increased as flow velocity decreased and these changes were related to the total ion concentration, the thickness of the diffuse double layer, and the zones of mobile and immobile solution.
Properties of Five Tropepts in a Toposequence of the Humid Tropics in Costa Rica
Authors: Martini J. A. , Mosquera L. 
Published: July 2010

AbstractFive Tropepts, in a toposequence developed under a warm humid climate, without a well‐defined dry season, were studied. The parent material varied from limestone in the pediment and upland soils to alluvium and colluvium derived from limestone and andesite in the terrace soils. Some andesitic volcanic ash contamination may have occurred from an adjacent volcano. The objective of this work was to characterize some of the physical and chemical properties, and to relate them to soil genesis, morphology, and performance in the greenhouse using tomato (Lycopersicon esculentum Mill.) as indicator plant. The occurrence of Tropepts and particularly Eutropepts under such climatic conditions was explained by the continuous rejuvenation of the soil parent material through alluviation, colluviation, landslides, and other forms of erosion. The calcareous parent material and possibly some contamination with volcanic ash may also have been a factor. These Tropepts had moderately thin sola, increasing in thickness at higher elevation in the toposequence. They have ochric epipedons and cambic horizons. Weathering, leaching, and profile development became stronger up‐slope where rejuvenation was not too drastic, as in the soils on the pediment backslope. Variations among profiles in this sequence were accounted for by changes in topography and parent material.
Colorimetric, Semiquantitative Test for Soil Salinity
Authors: Bower C. A. 
Published: July 2010

AbstractA colorimetric, semiquantitative test for soil salinity is described based on the equivalent release of yellow CrO4 ion upon reaction of Cl and SO4 with slightly soluble Ag2CrO4 and SrCrO4, respectively, to form less soluble AgCl and SrSO4.
Gaseous Losses of Nitrogen from Freshly Wetted Desert Soils
Authors: Macgregor A. N. 
Published: July 2010

AbstractOn the basis of manometric data and mass spectrometer analyses, N2 and N2O were formed when samples from the dry surface of two semiarid soils were moistened and incubated under argon for 22 to 42 hours at 38C.Of the endogenous soil nitrate‐N present in each soil, approximately 60% was volatilized by Pima clay loam (agriculture soil) and 0.6% was volatilized by Sonoita sandy loam (virgin desert soil). When either soil was amended with organic carbon, more gaseous nitrogen (N2 and N2O) was evolved than could be accounted for in terms of the initial level of endogenous nitrate.In 15N‐experiments, N2O was derived primarily from nitrate. However, although significant amounts of N2O were evolved by both soils, much of the N2O was unlabelled further suggesting nonnitrate sources play a role in volatilization of nitrogen from the soils under study.
An Infrared and Chemical Investigation of the Acid Tin Chloride Method of Determining Quinones in Humus
Authors: Mathur Sukhdev P. 
Published: July 2010

AbstractObservations of infrared spectral changes accompanying an acid SnCl2 treatment of soil humic preparations and a known quinone confirmed the effectiveness of SnCl2‐HCl for reducing quinones. The treatment did not reduce the nonquinoid but conjugated carbonyls of p‐hydroxy‐benzaldehyde, benzophenone, o‐benzoylbenzoic acid, chalcone, and curcumin. Recent criticisms of the technique were examined. It was proposed that due to the diversity in carbonyl frequencies, the variety of quinone groups and their derivatives, perhaps no single species of quinoid carbonyl was present in amounts adequate enough to be represented by a distinct peak in the spectra of unmodified humic compounds. Instead, there may have been several small peaks, all masked by the broad absorption bands due to other chromophores in the 1600‐ and 1700‐cm‐1 regions. Spectra of blends of fulvic acids (FA) with certain quinones, and naphtharesorcinol, supported the above concept. The 1600‐cm‐1 region of the FA spectra may have represented aromatic −C = C as well as quinones H‐bonded to ‐OH groups. In an indirect manner, this study furnished additional evidence for the presence of quinones in soil humus.
Field Calibration of Soil Tests for Available Zinc
Authors: Alley M. M. , Martens D. C. , Schnappinger M. G. , Hawkins G. W. 
Published: July 2010

AbstractLaboratory tests were calibrated for detection of soils supplying inadequate Zn for normal growth of corn plants (Zea mays L.). The available Zn tests under investigation were based on amounts of Zn extracted by 0.1 N HCl, dilute HCl‐H2SO4, ethylenediaminetetraacetic acid (EDTA), and diethylenetriaminepentaacetic acid (DTPA). The EDTA procedure gave the best separation of soils supplying either adequate or inadequate Zn for corn plants grown in the field. The “critical” level of EDTA‐extractable Zn for the 10 soils under study was approximately 0.8 ppm. Soils also were separated into Zn deficient and Zn sufficient categories by a three variable equation, Ŷ = 780.2 + 68.8X1 − 101.3X2 − 0.4X3; where Ŷ = Zn availability index, X1 = ppm dilute HCl‐H2SO4 extractable Zn, X2 = soil pH, and X3 = ppm dilute HCl‐H2SO4 extractable P. A Zn availability index of 135 gave the separation.
Response of Corn to Time and Rate of Phosphorus and Zine Application
Authors: Keefer R. F. , Singh R. N. , Horvath D. J. , Henderlong P. R. 
Published: July 2010

AbstractCorn (Zea mays L.) was grown in the greenhouse on two soils—Monongahela, a Typic Fragiudult (I) and Wharton, an Aquic Hapludult (II), which differed in available Zn, available P, exchangeable Mg, total Zn, and organic matter (OM). Dry matter yield and Zn concentration and content of plant parts were increased where Zn either as ZnSO4 or ZnEDTA was applied with P regardless of time to soil I (low in available Zn, total Zn, exchangeable Mg and OM). Zinc‐EDTA seemed to be a better source of Zn since it increased Zn concentration in leaves and stems more than ZnSO4 on soil I. However, with soil II (higher in available Zn, exchangeable Mg, and OM), response to ZnSO4 application was obtained only when P was applied at high rates 8 weeks before planting. Application of ZnEDTA produced no significant response by corn on soil II, probably due to instability of ZnEDTA under acid conditions resulting in appreciable amounts being fixed on the clays in this soil. The relative response to Zn with increasing levels of P (0 to 200 mg P/kg soil) was greater on soil I than on the soil II. Addition of Zn in the former decreased the percent P and P content in both leaves and stems at high levels of P application; however, application of Zn to the latter did not show any noticeable affect on percent P at all levels of P application.
Measurements of the Standard Entropy of Formation of Clay Minerals
Authors: Santillan‐Medrano Javier M. , Bohn Hinrich L. 
Published: July 2010

AbstractThe standard entropies of several clays were determined by calorimetry. The entropies of kaolinite and halloysite, 0.197 and 0.185 cal/g (50.8 and 47.7 cal/mole), respectively, compared well to literature values. The entropies of 2:1 layer‐lattice aluminosilicate clay minerals were within the range of 0.15 to 0.16 cal/g. The results for the 2:1 clays are considered questionable because of the problem of low thermal conductivity of these minerals. Problems of calorimetric measurements of clay minerals are discussed.
Some Observations on Soils‐Microclimate Interactions
Authors: Southard A. R. , Dirmhirn Inge 
Published: July 2010

AbstractThis paper reports data collected to relate some soil‐micro‐climate interactions. The environmental parameters examined were solar and scattered radiation evapotranspiration, calcium carbonate equivalent, organic matter, and particle size distribution. The data show a strong interaction between slope aspect or direction of exposure and soil properties. The need for careful observation of soil properties below the soil surface in selecting research sites is apparent.
Calcium, Magnesium, and Potassium Saturation Ratios in Two Soils and Their Effects Upon Yields and Nutrient Contents of German Millet and Alfalfa
Authors: McLean E. O. , Carbonell M. D. 
Published: July 2010

AbstractA greenhouse study involving sequential cropping of two soils of differing cation exchange capacities (CEC) with five Ca‐Mg saturation ratios at two K levels was conducted. German millet (one cutting, Setaria italica, German) followed by alfalfa (five cuttings, Medicago sativa, Saranac) was grown with Mg‐Ca saturations varied from Mg 5%–Ca 75% to Mg 25%–Ca 55% at two K levels.German millet yields were not affected by treatment of either soil. Similarly, alfalfa yields were not affected in the above range of Ca‐Mg saturations. However, an apparent Mg response occurred when alfalfa yields were more than doubled by increasing initial Mg and Ca saturations from 3 and 18% to 5 and 75%, respectively (concomitant pH increase from 5.4 to 6.8).Magnesium contents of plant tissue increased with increased Mg saturation, but soil K depressed the Mg content of the tissues more per equivalent than soil Mg increased it. The results indicate that for most conditions, 6–10% Mg saturation (high to low soil CEC) would likely be adequate for maximum yields of crops, although 12–15% may be indicated for supplying adequate Mg when grasses are to be grown for use as the main dietary constituent of ruminants.Exchangeable Mg and Ca contents in the soils after cropping plus amounts removed by cropping were less than the initial contents in one soil and were more than the initial contents in the other. Evidently some type of fixation mechanism tied up Mg and Ca in the former while solubilization of residual lime released them in the latter.
Rates of Growth and Nutrient Uptake of Irrigated Corn as Affected by N and P Fertilization
Authors: Bar‐Yosef B. , Kafkafi U. 
Published: July 2010

AbstractGrowth rates of corn and weekly uptake of major nutrients were measured in a permanent plot fertilization experiment. Bicarbonate‐soluble P and NO3‐N concentration in the soil were measured four times during the growing period. High levels of nitrates in the soil (140 ppm NO3‐N) during the first month of growth suppressed dry matter production. An increase in soil phosphate concentration resulted in higher phosphate uptake and early appearance of male flowers. On the control plots, which had not received any phosphatic fertilizer for 8 years, the plants took up more phosphate than the amount estimated by the bicarbonate method. The high levels of nitrates which were found in the soil 4 weeks after seeding (140 and 70 ppm N) dropped within the fifth week to a level of 20‐10 ppm N. Denitrification to gaseous compounds in the presence of living plants due to 68 mm of sprinkler‐applied water is proposed as an explanation of this phenomenon.In order to support satisfactory plant development, the soil must be able to supply at least 900 mg N and 100 mg P per week to each plant. Uptake flux values for P and N ranged between 2.6 and 22.8 × 10‐6 µg P cm‐2 sec‐1 and between 4.1 and 22.5 × 10‐5 µg N cm‐2 sec‐1, and were affected by plant age and fertilizer application.
Readily Oxidizable Carbon: An Index of Decomposition and Humification of Forest Litter
Authors: Hu Lily , Youngberg C. T. , Gilmour C. M. 
Published: July 2010

AbstractThe forest floor is an important component of the forest ecosystem. The reactions taking place at this interface between the organic horizons and the mineral soil are strategic. The rate of CO2 evolution from the forest floor is indicative of the biological activity occurring in the organic horizons and is also indicative of the readily available energy material present. The amount of CO2 evolved over a 28‐day period was determined for the F‐layers (decomposing material) and H‐layers (humified material) from hardwood, conifer, and mixed hardwood conifer forests in the northeastern United States. Total CO2 evolved appeared to be indicative of the level of readily oxidizable carbon in the material and its state of decomposition and humification. A more rapid method of evaluating decomposition and humification appeared desirable. Water soluble carbon was determined on the same materials used for the CO2 evolution study plus fresh litter from some of the same stands. The values for soluble carbon compared very favorably with those from CO2 evolution determinations. It was thus concluded that the more rapid soluble carbon determination is a useful index of state of decomposition and humification.
Microbial Competition for Glucose in Excised Root Experiments
Authors: Zwarun A. A. 
Published: July 2010

AbstractCompetition was determined by measuring 14CO2 evolution from the metabolism of 14C‐glucose by sterile roots or by roots with microflora present. Test solutions consisted of sterile 10‐4 M CaSO4 containing 1 µCi 14C‐glucose. A new technique was used to measure 14CO2. This technique does not rely on any wet chemical treatment and each analysis is completed in 72 sec. Treatments included sterile roots, nonsterile roots, and the microbial flora without roots. Sterile roots produced a low amount of 14CO2 from the 14C‐glucose. The nonsterile roots rapidly produced a copious amount of 14CO2. The low microbial inoculum without root material was dormant and did not produce any 14CO2. Apparently the microflora normally present during excised root experiments successfully competes with the root for glucose thus masking uptake attributable to the root.
Effect of Drying on Water Retention of a Puddled Soil
Authors: Taylor Howard M. 
Published: July 2010

AbstractMechanical energy applied to soil may disrupt the existing structure and increase water retention at a specific water potential. In this experiment, samples of puddled silty clay loam soil were predried to specified levels, then rewet. The effects of predrying on the water content‐potential relationships were determined.Puddling substantially increased water retention of the soil. If the puddled samples were ovendried at 110C prior to testing, water retention at all potentials between −1/5 and −15 bars was similar to nonpuddled soils. If the samples were predried to any water potential more negative than the test value, then rewet to near saturation, their water retention reverted toward that of samples in the nonpuddled state.
Application of Multispectral Remote Sensing to Soil Survey Research in Southeastern Pennsylvania
Authors: Mathews H. L. , Cunningham R. L. , Cipra J. E. , West T. R. 
Published: July 2010

AbstractComputer analyses of multispectral imagery collected from aircraft shows promise for reducing preparation time and increasing the accuracy of soil survey maps. The study area in southeastern Pennsylvania included soils formed from limestone, shale, sandstone, alluvium, and local colluvium. Four study sites ranging in size from 8.5 to 30 ha were selected from a 72 km flightline. Surface reflectance properties of nonvegetated fields were classified using pattern recognition techniques. Computer printout maps showing areal distribution of soil spectral classes were compared with field conditions. Limestone, shale, sandstone, and local colluvial soils were separated with a high degree of accuracy. Erosion classes separated by spectral maps were comparable in location and extent to field observations. The feasibility of preparing computer display maps for potential use as soil mapping aids was demonstrated.
Lindane Diffusion in Soil
Authors: Shearer R. C. , Letey J. , Farmer W. J. , Klute A. 
Published: July 2010

AbstractVapor and “nonvapor” diffusion of lindane was measured in Gila silt loam at various soil‐water contents. The apparent vapor diffusion coefficient (Dv′) increased rapidly as water content increased to 4%. There was a gradual decrease in Dv′ as water content increased from 4 to 20% and then a rapid decrease at water contents greater than 20%. The “nonvapor” apparent diffusion coefficient (Ds′) also reached a maximum at 4% water content and declined at water contents between about 4 and 20%. Ds′ increased as water content was increased above 20%.Apparently diffusion in the “nonvapor” phase occurs at the water‐air and water‐solid interface as well as in the water. The contribution of these pathways to the total transfer is dependent upon water content. It was assumed that the water‐solid diffusion coefficient would be constant at water contents above 4%. The air‐water interface diffusion was highest at 4% water content and decreased at higher water contents. Diffusion in water was essentially zero at water contents below 15% and increased with increasing water contents above this value.
Effects of Some Urease Inhibitors on Urea Hydrolysis in Soils
Authors: Bremner J. M. , Douglas L. A. 
Published: July 2010

AbstractStudies reported showed that, of eight urease inhibitors tested (2,5‐dimethyl‐p‐benzoquinone, catechol, p‐benzoquinone, hydroquinone, phenylmercuric acetate, N‐ethylmaleimide, sodium p‐chloromercuribenzoate, and acetohydroxamic acid), 2,5‐dimethyl‐p‐benzoquinone had the greatest ability to retard urea hydrolysis in soils and reduce gaseous loss of urea N as ammonia. Gaseous loss of urea N as ammonia from a urea‐treated sandy soil incubated at 20C for 14 days was reduced from 61.1% to 0.3% by addition of 2,5‐dimethyl‐p benzoquinone (2.3 parts/100 parts of urea).
The Chemistry of Fungal Humic Acid‐like Polymers and of Soil Humic Acids
Authors: Schnitzer M. , Ortiz de Serra M. I. , Ivarson K. 
Published: July 2010

AbstractA. niger, E. nigrum, and S. chartarum were grown in glucoseasparagine media according to Martin et al. The fungal “humic acids” synthesized were isolated, purified, and characterized by elementary and functional group analyses and by permanganate oxidation of methylated preparations. The oxidation products were separated by extraction into organic solvents, followed by preparative gas chromatography. The major components were identified by mass spectrometry and microinfrared spectrophotometry. The experimental data for the fungal “humic acids” were then compared with those obtained by identical methods on soil and peat humic acids.There were a number of similarities in surface functional groups between the fungal and soil preparations. The major oxidation products from the fungal materials were: (i) aliphatic mono‐ and dicarboxylic acids; (ii) benzenecarboxylic acids; (iii) phenolic acids; and (iv) aromatic compounds containing S and N. Compared with peat and soil humic acids, the fungal materials produced, per gram of initial material, relatively small amounts of aromatic but more aliphatic compounds. The E. nigrum “humic acid” yielded substantial amounts of n‐C14 to n‐C18 fatty acids. The results show that fungal “humic acids” are complex organic materials containing aliphatic and aromatic structures, only some of which are phenolic. Claims by Martin et al. that simple phenols and phenolic acids were significant constituents of fungal “humic acids” were not confirmed.
Ammonia Nitrogen Losses from Simulated Plowing of Native Sods
Authors: Hooker M. L. , Peterson G. A. , Sander D. H. 
Published: July 2010

AbstractThe objective of this research was to measure NH3 gas evolved from soils that have recently been broken from the native sod condition. Methodology for measuring NH3 losses under simulated natural environments is presented. Two moisture levels, field capacity, and wilting point were studied. It was concluded that NH3 volatilization was not a significant loss mechanism in the first 160 days after cultivation began.