bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical and Chemical Properties of Some Iowa Soil Profiles with Clay‐Iron Bands
Authors: Folks Homer C. , Riecken F. F. 
Published: July 2010

AbstractField and laboratory studies were made on some sandy soils of Iowa to determine the extent and nature of the clay‐iron bands which occur in some of these soils.Observations made in the field studies indicate that the iron and silicate clay enriched bands have a depth relation to the soil surface under virgin conditions. Also the bands occur often enough in loamy fine sand soils to indicate that the banding phenomenon is the usual rather than the exception in their genesis. Data obtained by fractionation of the < 2µ clay indicate differential movement of the clay fractions in 2 loamy fine sand profiles with iron and silicate clay enriched bands. In a sandy loam profile, no banding of iron and clay or movement of clay size particles was evident.Data from the chemical analyses indicate a very small quantity of bases held in the exchangeable form. Exchangeable base content of the iron band layers was of the order of twice as high as in the interband layers. Exchangeable Ca:Mg ratios were lower in the bands than in the interband layers. Exchangeable Ca:Mg ratios were higher in the profiles studied than those reported for other Gray‐Brown Podzolic and Brunizem soils which have developed from finer textured material. Total nitrogen was higher in the iron‐enriched bands than in the interband layers.In a laboratory experiment, iron bands were produced in a 1‐inch diameter, 4‐foot tube filled with iron containing fine sand by leaching with 0.01 N oxalic acid solution. Though visually evident, the bands were not sufficiently thick to sample for laboratory analysis. The development of bands in the laboratory is considered as additional proof that the bands of iron and clay enrichment observed in the field are the product of profile genesis. Upon drying, the sandy material in the upper part of the leaching tubes was quite strongly cemented.
Fertilizing the Subsoil for Better Water Utilization
Authors: Kohnke Helmut , Bertrand A. R. 
Published: July 2010

AbstractSubsoil fertilization experiments were conducted on several Indiana soils. The fertilizer was applied in vertical bands from 7 to 20 inches deep. The distance between the bands varied between 28 and 48 inches.The growth of corn roots greatly increased as a result of subsoil fertilization; subsoiling without fertilizing the subsoil increases root growth only slightly. Subsoil that was chiseled and fertilized maintained a higher porosity for over 2 years. The reason for the difference is probably the presence of additional organic matter (roots and microbes) in the fertilized subsoil.The subsoiled areas generally contained more moisture than the untreated plots, pointing to less runoff and erosion and to a greater water supply for the crops.Yield increases from subsoil fertilization have been substantial in many cases, but not consistent. It is assumed that benefits from this practice will increase as it is repeated on the same area.
Dynamics of Cation Exchange in Soil Columns
Authors: Bower C. A. , Gardner W. R. , Goertzen J. O. 
Published: July 2010

AbstractEquations for describing the process of ion exchange during passage of a salt solution through an exchanger column have been given by H. C. Thomas. N. K. Hiester, T. Vermeulen, and A. Opler have extended these equations and have provided graphic and numerical solutions.In the present study, the equations have been applied to the problem of determining the distributions of dissolved and adsorbed cations in soil columns as functions of depth and volume of solution applied. Two cases were studied: (1) saturation of soil initially free of the saturating cation by a solution containing only this cation, and (2) equilibration of soil having two cationic species initially present uniformly with a mixed solution of the two cations. For exchange between ion pairs of both equal (Mg and Ca) and unequal (Na and Ca) valence, the experimental results agreed quite satisfactorily with those predicted by the equations.
The Soil‐Vegetation Survey in California
Authors: Gardner Robert A. , Wieslander A. E. 
Published: July 2010

AbstractThis paper deals briefly with procedures and kinds of information currently being obtained in the soil‐vegetation survey of wild land in California and some of the problems encountered. The principal objective of the survey is to obtain accurate basic information on the kind and distribution of soils and natural vegetation, their relationships, and their characteristics and uses as an aid in better management of wild lands. The classification and mapping of both soils and vegetation follows a closely integrated procedure in which the skillful stereoscopic interpretation of aerial photographs plays an important part.
Photo Interpretation of Vegetation and Soils in Wild Land Areas of California
Authors: Nelson R. E. , Bradshaw K. E. , Wieslander A. E. 
Published: July 2010

AbstractThrough stereoscopic study of aerial photographs many features of the vegetation and also ground features can be directly identified. This has a practical application in mapping vegetation and soils in upland areas of California. This paper describes how vegetation types can be identified by analysis of the features visible on aerial photographs. It then describes how soil mapping is facilitated by photo interpretation of ground features, land form, and vegetation.
Uses of Soil‐Vegetation Survey Information in Watershed Management
Authors: Rowe P. B. , Colman E. A. 
Published: July 2010

AbstractManaging land for purposes of flood and erosion control and for maximum yield of usable water requires, among other things, knowledge of the hydrologic properties of soil in particular areas. Such knowledge can be obtained in the course of soil‐vegetation surveys if the surveys are planned to provide the needed kinds of information. This paper discusses the kinds of information required, and points out the need for improved methods of measuring the hydrologic characteristics of soils. In addition, it describes the hydrologic properties of three wild land soils in Mendocino County, California, and interprets these properties in terms of some of their watershed management implications.
The Fertility Status of Soils in Important Agricultural Areas of Colombia
Authors: Baird Guy B. , Rodriguez J. Manuel , Vega J. Victor M. , Aristizabal G. Alfonso 
Published: July 2010

AbstractField fertilizer trials were conducted in four of the important agricultural areas of Colombia. These areas were the Sinu and Cauca Valleys, the Savanna of Bogota, and the Mountains. Elevation ranged from about 70 to 10,000 feet above sea level with a correspondingly wide range in temperature, soils, and crops. Greenhouse pot tests with lettuce as the indicator crop and laboratory studies were made on samples of soils from field test sites.Soils from the Savanna of Bogota and the Mountain areas were found to be low in available P as shown by crop response in the field. Yield increases of about 40% were obtained with both potatoes and wheat by application of P fertilizer. There was little crop response to added N fertilizer, except in the Mountain area. With the exception of one soil, K was found to be present in ample quantities for the crops tested in all of the areas. There was a poor correlation between the field response to applied N and P, and the greenhouse and laboratory results under these widely different soil conditions.Mean values for soil pH were inversely related to the elevation of the areas. Values for pH ranged from 6.6 for the sample from the Sinu Valley (elevation 66 feet) to 5.2 for the Mountain area (elevation 7,000 to 10,000 feet). Mean organic matter content of the soil was positively related to the elevation. Mean values for organic C were 2.07 and 9.44% for the Sinu Valley and Mountain areas, respectively.
A Soil‐Column Study to Compare the Chemical Availability and Movement of Phosphates from Liquid and Dry Fertilizers
Authors: Langguth Robert P. , Brautigam George F. , Loveless L. E. 
Published: July 2010

AbstractThe chemical availability and movement of phosphates from liquid fertilizers and highly water‐soluble dry fertilizers were compared using four widely different California soils. Comparisons of the chemically available phosphate and migration of the phosphates were made at various time intervals after fertilizer application. The method used in determining chemically available phosphate was chosen because it has been reported as one of the best methods for correlating chemically available phosphate with plant growth.The availability of phosphate from liquid fertilizers was either equal to or greater than the phosphate availability from dry fertilizers having a highly water‐soluble phosphate source. The movement of the phosphate from the liquid fertilizer was essentially the same as that obtained from the dry fertilizers. While it is true that the quantity of applied phosphate remaining on the soil surface was greater from the solid fertilizers than from the liquid fertilizer, the amount of surface phosphate was only a small fraction of the total applied phosphate.
The Association between Free‐Water Evaporation and Evapotranspiration of Spring Wheat Under the Prevailing Climatic Conditions of the Plains Area of Montana
Authors: Army T. J. , Ostle B. 
Published: July 2010

AbstractIn a study involving over 25 years of crop and weather data at 2 stations in the Northern Plains of Montana, evapotranspiration of dryland spring wheat was negatively correlated with free‐water evaporation. In years of high temperatures and low rainfall, i.e., high free‐water evaporation, reduced crop growth and an inadequate supply of soil moisture resulted in low evapotranspiration.Cultural practice and geographic location influenced the amount of evapotranspiration per unit of free‐water evaporation. A greater amount of evapotranspiration per inch of free‐water evaporation always resulted under fallow than under continuous wheat.When adjustments were made for variation in size of plants (evapotranspiration/total dry weight ratio), the correlation between free‐water evaporation and evapotranspiration per unit of dry matter produced was positive. However, the degree of association between free‐water evaporation and the evapotranspiration ratio was apparently reduced by limited soil moisture supply.The effects of cultural practice, geographic location, and limited moisture supplies on the magnitude of evapotranspiration per unit of free‐water evaporation detract considerably from the value of free‐water evaporation measurements as an indication of water use by wheat plants under semiarid conditions.
Effect of Vegetation Upon Aggregation in Strip Mine Spoils
Authors: Wilson H. A. 
Published: July 2010

AbstractMaterial from vegetated and barren (nonvegetated) portions of strip mine spoils and adjacent unstripped soils were wet‐sieved through a series of standard mesh sieves. Five coal‐land strip mine spoils and two century‐old ironore spoils were sampled. The fractions remaining on each sieve were dried, weighed, and examined, using a stereoscopic microscope at a magnification of 15X. Differences in weight between the sieved fractions and the fractions remaining on the sieves from chemically dispersed samples were also determined. The actual aggregates, stones, and bits of coal were counted and the percentage aggregation calculated.The results show that the total weight of the wetsieved fractions from the vegetated (reforested iron‐ore spoils) and nonvegetated spoils is statistically less than that from the undisturbed soils. The percentage of aggregation in the coal‐land spoils is of the following order: nonvegetated < vegetated < undisturbed. The reforested iron‐ore spoils are not as well aggregated as the adjacent soils.The type of vegetation on spoils, as on soils, was also found to be an important factor in aggregation. In general, on these coal‐land spoils aggregation increases in the following order; based on the type of vegetation: nonvegetated < pine < locust < forage grasses and legumes.
The Retention and Reactions of Anhydrous Ammonia on Different Soil Types
Authors: McDowell L. L. , Smith G. E. 
Published: July 2010

AbstractSoil texture had a pronounced effect on ammonia movement and retention. The greatest movement of ammonia occurred in the sand and silt loam soils; and the least movement in the clay. The loss of ammonia from the airdry, acid sandy soil at a 6‐inch depth of application was 44 times the loss from the calcareous clay soil receiving ammonia at comparable moisture and depth. The retentive capacity of a soil for ammonia increased greatly as the texture became heavier. The loss of ammonia from the air‐dry, calcareous clay soil was negligible even at the 3‐inch depth of application. A considerable portion of the nitrogen applied as anhydrous ammonia was lost to the atmosphere or was fixed in some form making it non‐extractable by the chemical analysis used. The amount of ammonia fixed increased with the greater clay content of the soil.The presence of high concentrations of ammonia in a localized area resulted in the partial breakdown of the soil organic matter. As a result of nitrification and the subsequent increase in hydrogen‐ion concentration this condition was no longer observed at the end of 4 weeks of incubation.Ammonia losses were reduced considerably when the application was changed from 40‐inch to 16‐inch spacings and the rate applied per acre was maintained a constant.
The Potassium Status of Hartsells Fine Sandy Loam as Affected by Potassium Fertilization
Authors: Rouse R. D. 
Published: July 2010

AbstractThe K status of Hartsells fine sandy loam was characterized in the field by cropping for 18 years at rates of K ranging from 0 to 80 pounds per acre followed by 9 years of cropping without further additions. The K supplying power, exchangeable K, K content of cotton leaves, and cotton yield were determined annually during the residual period. These data indicate that the easily replaceable nonexchangeable K and the exchangeable K are both of value in sustained crop production.The rate of K application found to be adequate during the rate's study was inadequate when applied to former check plots until the application had been repeated annually for 5 or 6 years. It was found feasible to bring plots to a desired level of exchangeable K by discreet additions.
Sequence Relationships of Loess‐Derived Forested Planosols in Southeastern Iowa
Authors: Cain Charles C. , Riecken F. F. 
Published: July 2010

AbstractAccording to genetic theory, the loess‐derived soil series of southeastern Iowa can be arranged in a number of sequences. As for a number of other sequences studied previously, there is increasing clay in the Bt layer with decreasing loess thickness. The forested Planosols have an A1(Ap)A2BgC1 genetic horizon sequence. They have greater textural differences and a more abrupt boundary between the A and B horizons than any other sequence. In the forested Planosols, there is a secondary accumulation of N and organic P in the B horizon; the free Fe tends to accumulate in the A2B transition layer.
Spring Wheat Production and Soil and Water Conservation as Influenced by Methods of Summer Fallowing on a Chestnut Soil in Northeastern Montana
Authors: Power J. F. , Aasheim T. S. , Hartman G. P. 
Published: July 2010

AbstractFive methods of summer fallowing commonly employed in the spring wheat producing area of Montana were evaluated in respect to their effects on grain yield and quality, and on soil and moisture conservation. This study was conducted under dryland conditions on a Chestnut soil during the period 1949 to 1956.During seasons of normal or above‐normal growing conditions, grain yields were not significantly influenced by the method of fallowing employed the previous summer. Under poor growing conditions, grain yields were generally highest on plowed fallow.Protein content of the grain was slightly lower on stubble‐mulch than on plowed fallow. Test weights of the grain were highest on stubble‐mulch fallow. Other fallow methods were generally intermediate between plowed fallow and stubble‐mulch fallow in respect to grain quality.Soil‐moisture content at seeding time was not affected by fallow method. Stubble mulching provided the best soil erosion control. Fall tillage could not be recommended from the data collected in this study.
Available Water‐Holding Capacity of Alluvial Soils in Louisiana
Authors: Lund Zane F. 
Published: July 2010

AbstractA water‐holding capacity survey consisting of 22 profiles in Louisiana gave a positive correlation of 0.626 for silt and range of available moisture. Data indicated clay held moisture at suction values too high for plant availability. A negative relationship existed between sand and range of available water. Permeability was positively correlated with percent large pores.Many of the soils of Louisiana range from medium to fine texture and have large amounts of water available to plants. Permeability is a problem due to the low percent large pores.
Chestnut, Chernozem and Associated Soils of Western North Dakota
Authors: Mogen C. A. , McClelland J. E. , Allen J. S. , Schroer F. W. 
Published: July 2010

AbstractChestnut or Chernozem soils may occur in close association with Regosols, solonetzic soils and Calcium Carbonate Solonchaks, the Chernozems occurring in the moister northeastern portion. The morphology of these soils is discussed and some physical and chemical data are presented.
The Electric Balance Technique for Measuring the Mass and Charge of Clay Particles
Authors: Perrier Eugene R. , Evans D. D. 
Published: July 2010

AbstractThe electric balance technique, as employed by R. A. Millikan in measuring the charge of an electron, was used to simultaneously measure the mass and charge of individual kaolinitic, air‐dry clay particles. Also, it was possible with the same equipment to estimate the mass of the particles from the velocity of fall in air through the application of Stokes' law. A comparison of the two values is an evaluation of the error involved in using Stokes' law for kaolinitic clay particles.The mass could be measured to three significant figures in the range of 10‐12 g. by the electric balance technique, while to only two significant figures by the method involving Stokes' law. The calculated mass was from 0.0 to 80% higher by the former method than by the latter, which is an indication of the error from applying Stokes' law to irregularly shaped clay particles. The number of charges measured initially on the air‐dry particles ranged from 14 to 369. The nature and source of these charges were not determined.
Distribution of Fixed Ammonium in Soils
Authors: Stevenson F. J. , Dhariwal A. P. S. 
Published: July 2010

AbstractFixed ammonium was determined in 17 profiles representative of most of the great soil groups occurring within the North Central Region of the United States. The results showed that a vast reservoir of N exists in the terrestrial areas of the world as ammonium held within the lattice structure of clay minerals, thereby revealing a heretofore missing link in the N cycle.The amount of fixed ammonium in the soil was found to depend upon the type and amount of clay minerals present. With respect to clay mineral type, the order was illite > montmorillonite > kaolinite. Drainage, type of vegetative cover, and extent of leaching of the profile by percolating water had little effect on the fixed ammonium content of the soil. Cropping decreased the amount of fixed ammonium in surface soil; however, the fraction of the N present as fixed ammonium was greater for cropped soil than for uncropped soil.
Properties and Genesis of Finer Textured Subsoil Bands in Some Sandy Michigan Soils
Authors: Wurman E. , Whiteside E. P. , Mortland M. M. 
Published: July 2010

AbstractField and laboratory studies show that the nonlimy, more reddish, finer textured layers (Bt) found in the subsoils of three coarse‐textured soil profiles in Michigan contain a considerably higher concentration of silicate clay minerals and “free iron oxide” than the adjoining sandier layers. These layers also have slightly more organic matter than the adjoining sandier layers, and considerably less organic matter than the Bhir horizons in the same or associated profiles. These textural bands may or may not be from the same initial material as the horizons immediately above or below them. They are wholly or in part the result of pedogenetic processes.Both physical and chemical mechanisms are probably involved in the textural band formation. The existence of complexes of “free iron oxide”‐silicate clay‐organic matter in the soil and their ability to move through artificial columns containing natural nonlimy soil material was demonstrated in the laboratory. In addition, the movement of silicate clay and iron‐organic matter complexes simultaneously or at different times can be postulated. The deposition of the individual complexes or a combination of them may be caused by a chemical interaction between them, physical factors such as wetting and drying of the soil, or the activity of a third agency on one or both of the mobile constituents, e.g., free lime flocculating clay and/or organic‐iron complexes. Results indicate that a combination of the above mentioned factors is needed to explain the physical, chemical, and micropedological observations.
A Mineralogical Characterization of Some Loess‐Derived Soils in Illinois
Authors: Johnson P. R. , Beavers A. H. 
Published: July 2010

AbstractSix soil profiles representing successive stages of development in Peorian loess were studied by X‐ray diffraction to determine any changes in mineralogical composition of the silt fraction in relation to their maturity. The quartz, albite, and microcline contents were determined using NaF as an internal standard. The dolomite content was determined with the carbon‐induction furnace. The quartz content of the fine silt fraction increased progressively in the A horizons, did not change significantly in the B horizons, and increased slightly in the C horizons with distance from the loess source or bluff. Concomitant with the increase in quartz in the A horizons the feldspar content decreased, indicating the greater susceptibility of the latter to weathering. The slight increase in quartz content in the C horizons was due to the presence of dolomite in the younger soils and the absence of dolomite in the more mature soils. Quartz/feldspar ratios, an index of the weathering of the minerals, increased significantly for the fine silt fraction with increasing distance from the loess source. Albite weathered at a faster rate than microcline in the fine silt fractions. No significant change in the quartz and feldspar content of the coarse silt fraction was observed.
Integrating Soil Moisture Characteristics With Classification Units of Some Illinois Soils
Authors: Bartelli L. J. , Peters D. B. 
Published: July 2010

AbstractSoil moisture characteristics (15 atm., 1/3 atm., etc.) were determined for 31 soil types representing the major great soil groups recognized in Illinois. In addition such physical properties as bulk density and mechanical analysis were also determined for the principal soil horizons. Available soil moisture and field capacity was shown to vary by textural classes for each soil group studied. For example it was found that silt loam soils of the Gray‐Brown Podzolic averaged more available moisture in the A horizon than the Brunizems and Planosols. It was found that the available soil mositure was highly correlated with the 1/3‐atm. percentage but not correlated with the 15‐atm. percentage. The available moisture was controlled principally by the silt fraction.