bluuebunny/crossref_metadata_2025_split huggingface dataset:
Potassium in an Arid Loessial Soil: Characterization by Equilibrium Release‐Absorption to Strong Salt Solutions
Authors: James D. W. , Weaver W. H. 
Published: July 2010

AbstractShano silt loam soil developed from loessial and volcanic materials of recent origin under mild weathering conditions. It contains < 5% of clay, and 60% or more of silt. The rate of release of mineral K (Km) in this soil to 1N Cl solutions decreased in the order Na > Ca > Mg ≫ NH4. Release of Km may have involved some framework silicates, but for practical purposes the layer silicates controlled Km activity. Release of exchangeable K (Kx) graded imperceptably into Km release and apparently depended on the relative accessibility of edge‐interlattice adsorption sites. The classical method for estimating Kx (three extractions with NH4) evidently released some Km because the conformation of the cumulative solution K (Ks) curves was the same for initial NH4 extractions as for NH4 extractions following removal of Kx with Ca, Mg or Na. Based on the proportions and K‐releasing abilities of several soil size fractions, it was concluded that the preponderance of Km release activity originated in the silt fraction. A lesser amount of Km activity was associated with the sand with only a small portion of the Km release attributable to the clay. Equilibrium between Km, Kx, and Ks in the Shano soil was essentially complete within 24 hours.It appears that Km may be more important than Kx in this soil as pertaining to K intensity and capacity. In neutral and calcareous soils Ca and Mg are present in large amounts as exchangeable ions and as soluble and/or slightly soluble salts. Therefore, the activity ratio Ks/Nas potentially has greater significance in neutral to calcareous soils than do the potassium adsorption ratio K/[(Ca + Mg)/2]½ or quantity‐intensity relations, ΔKs vs. [K/(Ca + Mg/2)]½.
Potassium in an Arid Loessial Soil: Changes in Availability as Related to Cropping and Fertilization
Authors: James D. W. , Weaver W. H. , Roberts S. , Hunter A. H. 
Published: July 2010

AbstractTwo K fertilizer experiments were initiated in 1961 in arid central Washington on a Shano silt loam soil site that had been leveled to accommodate irrigation. The experiments were continued for 3 years and utilized rates of K fertilizer up to 320 kg K/ha in a randomized complete block design. By 1964 there existed a wide range of Kst (soil test K) as a result of the fixed random K treatments and the partial exposure of K‐deficient subsoils. That year the experiments were altered to completely randomized designs using both Kst and K fertilizer rates as controlled variables. The experiments were continued through 1970, providing an evaluation of the effects of crop management and K fertilization on soil K reserves.High Kst, both indigenous and fertilizer induced, decreased rapidly as a result of crop removal, with the rate of decline decreasing to zero as Kst fell below 100 ppm. The decrease in Kst was strongly modified by the type of crop (rooting habit and total K uptake) and by the method of crop residue disposition. Forage crops maximized the changes, whereas grain crops (with seed only removed) had a minimal effect, causing an apparent increase in K availability as a result of surface soil enrichment with K from the subsoil via the stubble. Decreases in Kst were stopped or reversed by K fertilization. Large amounts of K were removed by crops when Kst was low and static.At low levels of Kst soil mineral K (Km) had a dominating influence, strongly buffering Kst changes involved with K removal (cropping) and K addition (fertilization). Whereas Kst serves as a good first approximation of soil K supply potential, supplemental information is required to fully describe the intensity and capacity factors in the K‐soil‐plant system. At comparable levels of Kst, the Shano silt loam profile is essentially homogeneous in regard to K availability. Therefore, special efforts to sample subsoils need not be made in routine fertility diagnosis of this soil series.
Growth of Turfgrasses as Affected by Soil Phosphorus and Arsenic
Authors: Carrow R. N. , Rieke P. E. , Ellis B. G. 
Published: July 2010

AbstractThe influence of soil phosphorus (P) level on the growth of turfgrasses and on the Bray P1 extractable arsenic (As) were investigated. In the first study five rates of As (0, 0.44, 0.88, 1.76, and 3.53 kg As/100 m2) and four rates of P (0, 1, 2, and 4 kg P/100 m2) were applied to a soil low in natural P. In the second study four rates of As (0, 0.88, 1.76, and 3.53 kg As/100 m2) were applied to a soil collected from a long‐term P study. Several cool season turfgrasses were seeded in each study.Arsenic had no effect on seed germination of any of the grasses when the As was applied and incubated 7 weeks prior to seeding. Increasing As levels decreased the growth of all grasses regardless of P level. Poa annua L. was most affected by As. Phosphorus had little or no effect on As toxicity as exhibited by turfgrass growth even at very high P levels.Adding As increased the Bray P1 extractable As fraction. The Bray P1 extractable As level was negatively correlated to turfgrass growth. Phosphorus had no effect on As activity as measured by the Bray P1 extractable As. However, As markedly increased the P soil test results due to interference.
Loess in Ohio in Relation to Several Possible Source Areas: II. Elemental and Mineralogical Composition
Authors: Rutledge E. M. , Wilding L. P. , Hall G. F. , Holowaychuk N. 
Published: July 2010

AbstractThis study presents the elemental and mineralogical composition of thin loessial deposits eastward of three rivers in Ohio. In general, elemental contents (Ca, Fe, K, Ti, and Zr) of medium and coarse silts of the Late Wisconsin‐age loesses were of the same magnitude in each area. These elements showed remarkably slight weathering profiles which were essentially comparable among areas. Weathering profiles of Fe were more strongly expressed than those of K and Ca; depth‐distributions of Zr and Ti were most uniform. Contents of Ca within a Loveland loess paleosol were remarkably constant with depth and notably low, especially in the coarse silt fraction (mean of 0.06%). Mineralogy did not reflect bedrock lithologies among the different assumed loess source areas. Clay fractions from the parent loess in the first two transects were dominated by mica followed by vermiculite and quartz with less expandables and kaolinite. Clay fractions of surface and subsurface horizons in these transects contained about equal amounts of mica, vermiculite, and quartz with less expandables and kaolinite. In the third transect, weathered loessial materials generally contained less mica and more interstratified 10–14Å components. Clay‐free particle‐size distribution was the most sensitive parameter of parent material uniformity; total Zr and Ti in silt fractions, and Ti/Zr ratios were less sensitive in that order.
Vegetative History of Cinnabar Park in Medicine Bow National Forest, Wyoming
Authors: Miles S. R. , Singleton P. C. 
Published: July 2010

AbstractA study was initiated to determine the vegetative history and boundary stability of Cinnabar Park, a small park located in Medicine Bow National Forest, Albany County, Wyoming, typical of many high altitude parks scattered throughout our National Forest Lands.The park and the forest immediately surrounding the park occur on an erosional remnant of uplifted Tertiary aged sediments at an elevation of 2,758 m. The soils of the park are classified as Cryoborolls, and those of the forest surrounding the park are Cryochrepts. Vegetation in the park consists of a variety of forbs, shrubs, and grasses, while that of the surrounding forest is mainly lodgepole pine (Pinus contorta Dougl.), with some Engelmann's spruce (Picea engelmanni (Parry) Engelm.) intermixed.Various soil characteristics of the park were compared with those of the surrounding forest in an effort to obtain clues which might point to the vegetative history of this area. The content of plant opal and the pH of the soils, together with field observations, led to the conclusion that the park boundaries are slowly shifting in an eastward direction. Strong prevailing westerly winds and drifting snow appear to be the forces responsible for the boundary movement.
The Use of a Specific Ion Electrode for Determination of Bromide in Soils
Authors: Onken Arthur B. , Hargrove R. S. , Wendt C. W. , Wilke O. C. 
Published: July 2010

AbstractBromide has desirable characteristics for use as a tracer for NO3‐ in some soil studies. However, its quantitative determination in the presence of Cl‐, which occurs in interfering quantities in many soils, requires lengthy procedures. Further, Br‐ interferes with the quantitative determination of Cl‐ for which concentrations may also need to be determined. To facilitate the use of Br‐ as a tracer in such tests, a procedure for the rapid and accurate determination of water‐extractable Br‐ in the presence of Cl‐ and Cl‐ in the presence of Br‐ was developed. These quantitative determinations over a wide range of concentrations were accomplished by use of standard curves, interference curves, and successive approximations. Bromide added to soil over a wide range of concentrations was quantitatively recovered.
Bulk Density, Saturation Water Content and Rate of Wetting of Soil Aggregates
Authors: Gumbs F. A. , Warkentin B. P. 
Published: July 2010

AbstractBulk density, degree of saturation, volume increase on wetting, and rate of wetting were measured for aggregates and clods of Ormstown silty clay loam (Humaquept) of sizes from 5 cm to 0.036 cm diameter.Bulk density increased with a decrease in diameter. For 2.2‐mm to 0.36‐mm diameter aggregates this increase was due to a surface area effect, i.e., loss in porosity as a result of subdividing larger aggregates. Both surface area effects and increased porosity from root channels and fissures were required to explain the increase for clods between 5 and 1 cm diameter.An evaporation and a sorption technique are described and used to estimate the water content of aggregates at saturation, i.e., the intra‐aggregate water content. The evaporation technique gave reliable results at specific rates of evaporation, but the sorption technique was not as useful. Clods and aggregates of the soil and of pumice samples did not fully saturate; entrapped air accounted for 25 to 27% of the total pore volume.Aggregates of 1 and 2.2 mm diameter and clods of 1.0 and 5.0 cm diameter took about 1, 1.7, 45, and 1,000 seconds, respectively, to saturate. This rapid wetting would minimize differences in potential between inter‐and intra‐aggregate water during infiltration.
Gaseous Loss of Ammonia from Sulfur‐coated Urea, Ammonium Sulfate, and Urea Applied to Calcareous Soil (pH 7.3)
Authors: Prasad M. 
Published: July 2010

AbstractLaboratory incubation experiments were conducted to study the comparative volatilization loss of NH3 in a calcareous soil from sulfur‐coated urea (SCU) with fast (F), medium (M), and slow (S) dissolution rates, ammonium sulfate (AS) and urea, at two temperatures 22 and 32C, and at three soil moisture levels 25, 50, and 80% of the water‐holding capacity of the soil. The effect of the addition of organic amendment (filter press mud) to soil on NH3 loss from these N‐sources was also studied. Losses were studied up to 21 days. At both temperatures increasing soil moisture levels led to reduction of NH3 loss regardless of the N‐source, despite the fact that the soil analysis showed higher dissolution of N from SCU at high soil moisture.Higher temperature increased the NH3 losses from all N‐sources. Losses usually followed the order of Urea > AS > SCU(F) > SCU(M) > SCU(S). At 32C losses from uncoated urea and AS at low, medium, and high moisture were 20.6 and 16.7%; 14.5 and 13.1%, and 8.4 and 6.6% of the N application rate, respectively. Losses from SCU(F) and SCU(M) as percentage loss of uncoated urea varied from 34% and 26% at low moisture, 29% and 23% at medium moisture, and 28% and 23% at high moisture, respectively. At 22C losses from uncoated urea and AS at low, medium, and high moisture were 11.1 and 10.2%; 7.7 and 8.8%, and 4.2 and 3.5% of the N application rate, respectively. Losses from SCU(F) and SCU(M) at three moisture levels were 26 and 17%, 18 and 10%, and 24 and 16%, respectively.Incorporation of filter press mud to the soil resulted in reduction of volatilization loss of NH3 from all N‐sources which was partly due to exchange reaction and biological immobilization of NH4‐N and partly due to reduction of urease activity.
Soils and Stratigraphy of Mid to Lower Slopes in the Southwestern Uplands of Nigeria
Authors: Ojanuga A. G. , Lee Gerhard B. , Folster H. 
Published: July 2010

AbstractPedogenic and geomorphologic studies along mid to lower slopes of typical landforms in southwestern Nigeria revealed simple to complex stratification of pedisediments derived through cyclic erosional and depositional phenomena that evolved the inselberg landscapes in the region. The most recent pedimentation of slopes and hence, the deposition of the youngest soil parent material, is believed to have occurred about 2360 ± 120 years before the present. Contemporary soils owe many of their major properties to depositional processes. Pedogenic processes that could be inferred from existing soil properties include: the addition of organic matter to surface horizons, strong leaching of bases, eluviation of iron oxides from surface layers, lateral translocation of iron oxides, incrustation of subsoil concretionary materials to form petroferric horizons (hardpan) in lower slope positions, and clay migration.
Drainage System Effects on Physical Properties of a Lakebed Clay Soil
Authors: Hundal S. S. , Schwab G. O. , Taylor G. S. 
Published: July 2010

AbstractThe long‐term effects of drainage on physical properties of a lakebed silty clay soil were evaluated 16 years after initiation of a field experiment. The treatments were undrained, surface drainage, subsurface drainage, and a combination of surface and subsurface drainage. Soil conditions were characterized by surface penetration resistance and by unconfined compressive strength, hydraulic conductivity, and pore size distribution in the 0–30 cm depth. Subsurface drainage resulted in greater soil hydraulic conductivity, less unconfined compressive strength, and less surface crust resistance than treatments without subsurface drainage. Subsurface drainage also decreased bulk density and increased the volume of air‐filled pores at 0.02 to 1.0‐bar suctions, but these effects were of smaller magnitude.An alfalfa (Medicago sativa L.)‐timothy (Phleum pratense) mixture was grown during the period of these measurements. The survival of alfalfa and the total hay yield decreased in the order: combined surface and subsurface drained, subsurface drained, surface drained, and undrained treatments.
Polymerization of Aromatic Molecules on Smectite
Authors: Mortland M. M. , Halloran L. J. 
Published: July 2010

AbstractWhen benzene or phenol are adsorbed on smectite containing Fe(III) or Cu(II) on the exchange complex, higher molecular weight products are formed. Evidence for these products is provided by mass spectroscopy. In the case of benzene most of the reaction products cannot be attributed to coupled benzene rings, while extensive coupling occurs for phenol. Electron spin resonance spectroscopy provides evidence for radical cation formation of the aromatic molecules. The involvement of these radical cations is thus proposed in the formation of the higher molecular weight species. The relevance of these reactions to the natural systems of soils and sediments is suggested.
Influence of Cation Content on the Biological Activity of Fensulfothion in Plainfield Sand
Authors: Harris C. R. , Bowman B. T. 
Published: July 2010

AbstractA study was conducted to assess the influence of cations on the biological activity of the organophosphorus insecticide, fensulfothion (O, O‐diethylO‐[p‐(methylsulfinyl)phenyl] phosphorothioate)(Dasanit®) in soil. Bioassays were done using first stage crickets, Gryllus spp. as test insects and a Plainfield sand without and amended with various concentrations of reagent chloride salts of NH4+, K+, Ca2+, Fe3+, and Al3+. The toxicity of fensulfothion decreased with increasing cation content, with the effect being most pronounced with trivalent > divalent > monovalent cations. Results of the bioactivity study paralleled those of an earlier adsorption study on fensulfothion‐cation montmorillonite suspensions.
Biosynthetic Alteration in a British Columbia Soil by Ants (Formica fusca Linné)
Authors: Wiken E. B. , Broersma K. , Lavkulich L. M. , Farstad L. 
Published: July 2010

AbstractThe occurrence and pedological effects of active and recently active (inactive) ant mounds are compared with apparently unaffected soils in the subalpine region of Mt. Tatlow in British Columbia, Canada. The unaffected soils in the area are classified as Orthic Dystric Brunisols (Dystrochrepts). The soils have developed from post‐Pleistocene glaciofluvial deposits and support a lodgepole pine‐pine grass vegetative community. Comparison of the active and inactive colonies with the surrounding unaffected soils showed marked changes in particle size distribution, chemical properties, and structure formation. The biosynthetic alteration generated by ants (Formica fusca Linné) appears to reverse the general pedogenetic processes of leaching and horizonation. This process is only temporary as the inactive sites are similar to the surrounding unaffected soils.
Effect of Water Supply, Nitrogen, and Seedbed Density on White Spruce Seedling Growth
Authors: McClain K. M. , Armson K. A. 
Published: July 2010

AbstractSeedling dry weight, height, and root area index were measured during the second (2 + 0) growing season for white spruce (Picea glauca (Moench) Voss) seedlings grown in a field nursery at two seedbed densities, three levels of moisture supply, and four levels of N. All measures of growth increased with rise in N supply. Increases were more pronounced at the lower than at the higher seedbed density. Growth responses to increases in moisture supply varied in relation to N level but were consistently greater at the lower density. Seedling foliage at final harvest was analyzed and concentrations of the major elements (N, P, K, Ca, and Mg) determined. Nitrogen concentrations increased with increasing N supply and decreasing moisture. Other nutrient elements were variably affected, but did not limit growth.
The Effect of Controlled‐Availability Nitrogen Fertilizers on Mature Pecan Trees
Authors: Sullivan D. T. , O'Connor G. A. , Herrera‐Aguirre E. 
Published: July 2010

AbstractTwo controlled‐availability N fertilizers, sulfur‐coated urea (SCU) and NH4NO3 plus N‐Serve, were compared with NH4NO3 alone applied to 30‐year‐old pecan trees (Carya illinoensis Koch) in a 2‐year study. Leaf N contents were increased in both years by N fertilization, but yield and nut weight were not significantly affected. Yields in 1973 were correlated with 1972 leaf N contents, but not with 1973 leaf N contents. The SCU treatment was effective in controlling N release in 1973, but not in 1974. The N‐Serve treatment was ineffective both years of the study. The ineffectiveness of the controlled N sources were attributed to: (i) poor incorporation of the materials, (ii) inherent slow response of mature pecan tree to N fertilization, and/or (iii) sufficient variability within treatments to mask fertilizer source difference.
Changes in the Physical Properties of Soil Clays due to Precipitated Aluminum and Iron Hydroxides: II. Colloidal Interactions in the Absence of Drying
Authors: El‐Swaify S. A. 
Published: July 2010

AbstractColloidal stability diagrams were constructed for suspensions of an illite, a kaolinite, and a mixture of the two into which Al(OH)3 and Fe(OH)3 were precipitated. These diagrams covered a pH range from 2.5 to 12.5 and electrolyte concentrations up to the flocculation value. It was revealed, in accordance with expected interactions of colloids with widely different isoelectric points, that the colloidal stability of each mixture was dependent on the charge balance between its individual constituents. Therefore, as long as a system has not encountered a drying cycle, hydroxides may provide favorable (flocculating) or nonfavorable (colloidally stable) effects on soil structure depending on hydroxide type, its surface reactivity, and the clay mineral with which it may be associated. Generally, the two hydroxides provided equal enhancement of clay colloidal stability above their isoelectric points. However, Al(OH)3 was more active in inducing clay flocculation and charge reversal at low pH values.
Ammonia Volatilization and Nitrogen Utilization from Sulfur‐coated Ureas and Conventional Nitrogen Fertilizers
Authors: Matocha J. E. 
Published: July 2010

AbstractAmmonia volatilization was measured on acid and calcareous soils receiving sulfur‐coated ureas (SCU) and highly soluble N fertilizers. Surface and mixed applications of SCU‐30 (30% dissolution rate), SCU‐20 (20% dissolution rate), uncoated (NH2)2CO, NH4NO3, and (NH4)2SO4 were made with and without lime to a fallowed acid fine sand. Without lime, top dressed NH4NO3, SCU‐20, SCU‐30, and (NH4)2SO4 lost < 1% while (NH2)2CO lost 18.5% of added N in 14 days. Topdressing lime with N caused more NH3 loss from (NH4)2SO4 than from (NH2)2CO during the intial 48 hours. However, accumulative losses for 14 days were 51.5, 22.5, 9.0, and 1.7% from (NH2)2CO, (NH4)2SO4, SCU‐30, and SCU‐20, respectively. Incorporating the lime with the soil prior to N addition reduced NH3 loss > 50% as compared to surface application, but mixing N with the limed acid soil did not reduce NH3‐N losses. Mixing SCU with the soil appeared to increase release rate of N over topdressing, but this effect was not detected in plant response. Nitrogen uptake by corn (Zea mays L.) on the acid soil substantiated some of the conclusions regarding measured NH3‐N losses.Ammonia losses from N mixed with the finer textured calcareous clay loam were generally insignificant. Surface applied (NH2)2CO and (NH4)2SO4 lost significant amounts of NH3‐N, while losses from SCU and NH4NO3 were negligible.
Microcalorimeter Adaptation for Measurement of Heats of Adsorption at Solid‐Solution Interfaces
Authors: Harter Robert D. , Kilcullen Brian M. 
Published: July 2010

AbstractThe sensitivity of the Calvet Microcalorimeter makes feasible the measurement of very small heats of reaction. This capability is particularly useful when studying adsorption reactions at solid‐solution interfaces. The instrument must, however, be specially adapted for measurements of this type, since it contains no provision for equilibration and mixing of separate solutions. Previously developed adaptations of the instrument are not satisfactory, because they either do not stir the combined solutions adequately to overcome flocculation problems or their mechanical energy input is high. An instrument has been developed whereby two solutions can be equilibrated in the calorimeter cell, then mixed and stirred with a net mechanical energy input of −2 ± 0.4 mcalories. This instrument, therefore, makes possible the precise measurement of very small heats of reaction.
A Portable Rainfall Simulator for Erodibility and Infiltration Measurements on Rugged Terrain
Authors: Munn J. R. , Huntington G. L. 
Published: July 2010

AbstractA portable rainfall simulator for field study of erosion potential and infiltration on mountainous terrain is described. Polyethylene tubes produce 3.2‐mm drops which fall 2.5 m onto a 61 by 61 cm plot. The maximum rainfall intensity is 23 cm/hour. A 16% intensity variation across the plot area was measured, but the variation between separate simulated storms was < 1% for identical intensity settings. The unit is suited to one man operation on slopes up to 60%.