bluuebunny/crossref_metadata_2025 huggingface dataset:
SILICA IN SOIL SOLUTIONS: I. THE FORM AND CONCENTRATION OF DISSOLVED SILICA IN AQUEOUS EXTRACTS OF SOME SOILS
Authors: McKeague J. A. , Cline M. G.
Published: March 2010

The effects of method of equilibration, soil-water ratio, pH, and temperature on the form and concentration of dissolved silica in soil-water mixtures were studied and some hypotheses concerning the role of soluble silica in soil development were evaluated in the light of the information obtained.Studies of methods of equilibrating soil-water mixtures showed that, with medium- and coarse-textured soils, shaking for a month resulted in increasing concentrations of dissolved silica with time. Concentrations of dissolved silica in similar mixtures that were allowed to stand were much lower and they changed very slowly with time after a few days. Shaking techniques are not suitable for obtaining equilibrium water-extracts of some soils.Concentrations of dissolved silica in water extracts of the soils studied increased with temperature and with soil-solution ratio, and decreased with increasing pH. The dissolved silica concentration of extracts of different soils ranged from less than 1 to more than 20 p.p.m. Monomeric silica, presumably Si(OH)4, was the form of dissolved silica in all of the extracts studied. This result discounts hypotheses of soil genesis involving silica sol.
SILICA IN SOIL SOLUTIONS: II. THE ADSORPTION OF MONOSILICIC ACID BY SOIL AND BY OTHER SUBSTANCES
Authors: McKeague J. A. , Cline M. G.
Published: March 2010

A study was made of the adsorption of monosilicic acid from dilute solutions by soils and other solids and the results were applied to a consideration of silica in natural soil solutions. Freshly precipitated hydroxides of polyvalent metal ions were most effective, some soil samples and iron-oxide minerals were moderately effective, and alkaline-earth carbonate minerals were ineffective in adsorbing dissolved silica. The adsorption data approximately conformed to Freundlich's adsorption equation. Adsorption of Si(OH)4 increased throughout the reaction range pH 4 to pH 9 and, with a ferruginous soil sample, adsorption decreased as the pH was increased above 10.The data obtained support the hypothesis that a pH-dependent adsorption reaction is involved in controlling the concentration of silica in soil solutions. Adsorption of Si(OH)4 as soil moisture evaporates may contribute to the accumulation of amorphous coatings on soil particle surfaces.
THE EFFECT OF FERTILIZER ON GROWTH, NUTRIENT UPTAKE AND MOISTURE USE OF WHEAT ON TWO SOILS IN SOUTHWESTERN SASKATCHEWAN
Authors: Warder F. G. , Lehane J. J. , Hinman W. C. , Staple W. J.
Published: March 2010

The use of NP fertilizer gave consistent increases in yields of wheat on a loam and a clay soil with low NaHCO3 soluble phosphorus contents. The fertilizer increased crop growth during the early part of the growing season hastened maturity, and increased the amount of stooling and the number of mature heads at harvest time.Fertilized crops on both soils used more moisture than unfertilized crops between seedtime and the heading stage. For the season as a whole, no difference in total moisture use was recorded on loam soils between fertilized and check crops but on clay soil some fertilized crops extracted more subsoil moisture than the unfertilized crops.Under the climatic conditions of these experiments yield responses obtained from fertilizer application did not appear to be directly related to the amount of available moisture at seedtime or to the seasonal precipitation. When increased yields were obtained from the use of fertilizer the fertilized crops used moisture more efficiently.The NP fertilization had little or no effect on the phosphorus content of the grain but did increase the total phosphorus uptake by the crops. The fertilizer treatment increased the protein content of wheat grown on stubble on both the loam and the clay soils and on two of the four crops grown on fallow on the loam soil.
EFFECTS OF LIME, NITROGEN AND PHOSPHORUS ON THE RESPONSE OF LADINO CLOVER TO MOLYBDENUM
Authors: Ouellette G. J.
Published: March 2010

A chlorosis of Ladino clover, which was attributed to a shortage of molybdenum on St. Onesime stony loam, did not appear unless sufficient superphosphate was applied. An excessive amount of superphosphate has rendered the chlorosis more acute. The situation could be corrected by applying to the soil either 1 pound of sodium molybdate or 100 pounds of ammonium nitrate or 2 tons of limestone. This tends to prove that the trouble was one of nitrogen deficiency induced by the lack of molybdenum. Greater yield increases could be obtained, however, with additions of nitrogen or limestone than of molybdenum. Therefore, the latter could not take the place of the former, at least not completely but, under the conditions of the experiment, the reverse seemed possible. Tissue content of molybdenum, nitrogen and phosphorus correlated with growth data.
MEASUREMENT OF THE POLYSACCHARIDE CONTENT OF SOILS
Authors: Acton C. J. , Paul E. A. , Rennie D. A.
Published: March 2010

The polysaccharide content of two soils, measured by precipitating and weighing the microbial gums from the fulvic acid fraction of soil organic matter, and by colorimetric analyses using anthrone, was increased appreciably during the incubation of samples with straw. Applications of nitrogen and phosphorus altered only slightly the amount of polysaccharides present. The polysaccharide content of the amended soils increased rapidly during the first week of incubation and then levelled off.Peptization of the soil with dilute alkali prior to acid hydrolysis substantially increased the carbohydrates measured with anthrone. The anthrone reagent which measures primarily hexoses indicated a soil carbohydrate content of 10–15 per cent occurring in a range of Saskatchewan soils. Thirty-five per cent more carbohydrate carbon was found using the less specific phenol-sulphuric acid reagent.The acetone precipitated fraction from the fulvic acids accounted for only 10 per cent of the soil carbohydrates and contained a large proportion of ash and other non-carbohydrate materials. The total acid-soluble base-soluble fraction, fulvic acids, contained 15–25 per cent; the remainder was distributed in the alkali insoluble humin — 55–70 per cent and the humic acid fraction 4–12 per cent.
CARBON BONDED SULPHUR IN SELECTED QUEBEC SOILS
Authors: Lowe L. E. , DeLong W. A.
Published: March 2010

Details are given of a procedure for the determination of carbon bonded sulphur in soils and soil extracts.Significant amounts of carbon bonded sulphur were found in a few selected Quebec soils. Organic soils contained substantially more carbon bonded sulphur than mineral soils, and also a higher proportion of the total sulphur was in a carbon bonded form in the organic (47–58 per cent) than in the mineral soils (12–35 per cent).The distribution of carbon bonded sulphur between acid-extractable, alkali-extractable and non-extractable fractions was determined on the same samples. The recovery of carbon bonded sulphur in these fractions was high in the organic soils, but 16–48 per cent was not accounted for in three mineral surface soils. For all samples, very little carbon bonded sulphur was non-extractable and, in all samples, except a podzol B21 horizon, more of this sulphur fraction was extracted by alkaline than by acid extraction.The importance of this fraction as a source of sulphur for plants cannot yet be assessed.
EFFECT OF INTENSITY OF CROPPING ON THE EFFICIENCY OF WATER USE
Authors: Ferguson W. S.
Published: March 2010

An experiment conducted at Brandon, Manitoba, during the years 1955–1959 inclusive, indicated that the proportion of the total rainfall lost to the atmosphere from plant and soil surfaces on cropped land during the growing season (hereafter referred to as evapotranspiration) was highly dependent on the intensity of cropping. Evapotranspiration accounted for only 38.3 per cent of the total rainfall in a wheat-summerfallow rotation. The remaining 61.7 per cent was lost by percolation, run-off and/or evaporation during the non-crop period of the rotation. Decreasing the frequency of summer-fallow in the rotation increased the percentage of the total rainfall used by evapotranspiration. This percentage increased to 78.5 when wheat was grown continuously. Evapotranspiration accounted for 90.8 per cent of total rainfall with alfalfa. Evapotranspiration by wheat grown on summer-fallow tended to decrease when fertilizer was used and increased when third crop wheat was fertilized. The changes resulting from fertilizer were small, relative to the changes resulting from the intensity of cropping. The use of fertilizer increased the number of bushels of wheat produced per inch of evapotranspiration. This was determined mainly by the fact that fertilizer increased the yield and not because of decreased evapotranspiration. Summerfallow was not necessary to conserve moisture for wheat production during the experimental period.
SOLUBILITE ET FINESSE DE MOUTURE DE DIVERS FERTILISANTS BORATES
Authors: Oueixette G. J.
Published: March 2010

not available
NOTE ON HOT WATER BOTTLE LYSIMETER
Authors: Holmes R. M.
Published: March 2010

not available
A STUDY OF THE MINERALOGICAL COMPOSITION OF SAND IN NORTHERN ONTARIO
Authors: Dell Carol I.
Published: March 2010

A preliminary study of the mineralogical composition of the fine sand fractions of 51 samples of tills and stratified sands in northern Ontario was carried out. About 40 different minerals were identified in widely varying amounts. In all but a few samples, feldspar was the most abundant mineral while quartz was never the most abundant. Several deposits containing Palaeozoic limestone and dolomite fragments from the rocks of the James Bay lowlands were quite similar in composition to the calcareous southern Ontario deposits. Other samples, containing large amounts of pyroxenes, shale fragments or "greenstones", differed greatly from similar deposits in southern Ontario. The composition of the fine sand correlated well with the field classification of soils in this region, with a few exceptions.
THE INFLUENCE OF THE META-STABLE TRIPLE POINT SOLUTION OF MONOCALCIUM PHOSPHATE MONOHYDRATE UPON THE CLAY SEPARATES OF TWO ONTARIO SOILS
Authors: MacKenzie A. F. , Campbell C. A.
Published: March 2010

Samples of material less than 2 μ in diameter were obtained from the surface horizon of a Guelph loam and of a Haldimand clay loam. These samples were subjected to six successive treatments with the meta-stable triple point solution of monocalcium phosphate monohydrate (MTPS) to simulate the environment near a dissolving superphosphate granule. Samples of montmorillonite and illite standard clays were also included. The dissolution losses in per cent were: Guelph clay 59.5, Haldimand clay 40.4, montmorillonite 3.4, and illite 8.1. Total chemical analyses, X-ray diffraction techniques, differential thermal analyses and electron microscope observations were used to determine the nature of these losses. In the soil clay separates, vermiculite and interstratified montmorillonite were more susceptible to the action of MTPS than were the illite or halloysite clay minerals.
CHARACTERISTICS OF THE CLAY FRACTIONS IN A CHERNOZEMIC TO PODZOLIC SEQUENCE OF SOIL PROFILES IN SASKATCHEWAN
Authors: St. Arnaud R. J. , Mortland M. M.
Published: March 2010

The clay fractions of four Saskatchewan soils ranging from Orthic Black to Orthic Grey Wooded have undergone small but significant changes as a result of pedogenic processes. The fine clay fractions (< 0.2 μ) are composed almost entirely of montmorillonite and illite which occur in a ratio of approximately three to one. Trace amounts of kaolinite and chlorite are present. Montmorillonite and illite, occurring in about equal amounts in the coarse clay fractions (2.0—0.2 μ), account for less than three-quarters of the total weights; kaolinite, chlorite and primary minerals make up the remainder of the fractions.The fixation of potassium by expanding-type clay minerals has resulted in an increase in illite content within the sola of all four profiles. Illitization is most pronounced in the Ah horizon of the Black soil. The chlorite content of the clays decreases within the sola of all profiles, the greatest decrease occurring in the Ae of the Grey Wooded soil, indicating more intensive weathering in the Podzolic than in the Chernozemic soil.Surface area and cation exchange capacity data substantiate, to some degree, currently held views on the close relationship between micas and expanding 2:1 layer silicate minerals in soils. The lack of preferential movement of montmorillonite within profiles in which marked clay translocation has occurred may serve as a good indication that montmorillonite and illite occur as interstratified clays and as such cannot move separately within these soils.
NOTE ON THE COLLECTION OF ORGANIC SOILS IN SITU FOR PHYSICAL PROPERTY TESTS AND MOUNTING OF PROFILES
Authors: Stanek Walter
Published: March 2010

not available
NOTE ON A METHOD OF STUDYING SUBSOILS IN THE GREENHOUSE BY MEANS OF A LYSIMETER
Authors: Beauchamp E. , Steppler H. A.
Published: March 2010

not available
A THERMOGRAVIMETRIC STUDY OF ORGANIC MATTER OF REPRESENTATIVE CANADIAN PODZOL SOILS
Authors: Schnitzer M. , Turner R. C. , Hoffman I.
Published: March 2010

Differential thermogravimetric (DTG) curves of untreated peat, muck, and 10 different Podzol L–H materials showed peaks at approximately 100 °C (moisture), 280° (low-temperature band), and 370 to 390 °C (high-temperature band). The maxima at 280 °C were sharp and characteristic of all surface materials investigated. The DTG curves were essentially the same for all of the Podzol L–H materials investigated.The DTG curves for 12 organic matter preparations extracted from Podzol Bh, Bfh, Bhf, Bfl, and Btf horizons showed maxima at 100 °C and in the 420 to 520 °C region (high-temperature band). The peaks at 280 °C were virtually absent in these materials. This suggested differences in composition between L–H and B horizon organic matter of the Podzols studied. The variations in the positions of the high-temperature bands of the B materials were related to the morphological characteristics of these soils in the field. From this it appeared that thermogravimetry might be a useful aid in soil classification.Addition of inorganic materials did not affect the position of the low-temperature bands but had a pronounced effect on the high-temperature bands of both L–H and B organic matter. Addition of Na caused the peaks of the latter to shift to higher temperatures while addition of Al and Fe caused shifts to lower temperatures.
FERTILIZER RESPONSE OF FORAGE CROPS IN THE UPPER KOOTENAY RIVER VALLEY
Authors: Lutwick L. E. , Krogman K. K.
Published: March 2010

Phosphorus and nitrogen fertilizers applied to plots of irrigated Saha silt loam increased the yield of alfalfa and of grass from [Formula: see text] and [Formula: see text] ton per acre, respectively, to 4 and [Formula: see text] tons per acre, respectively.Alfalfa showed no yield response to boron or sulphur.The NaHCO3-soluble phosphorus content of the soil after 3 years of cropping was affected by the level of both phosphorus and nitrogen fertilizers.Low soil fertility without applied fertilizers is as much a limiting factor as lack of moisture without irrigation for the production of forage crops on the Saha silt loam.
THE RELATIONSHIP OF EXCHANGEABLE CATIONS IN THE B HORIZONS TO THE FIELD SEPARATIONS OF SOLONETZIC AND CHERNOZEMIC SOILS
Authors: Ballantyne A. K. , Clayton J. S.
Published: March 2010

Exchangeable cation data are presented for 97 Solonetzic and 131 Chernozemic B horizons from profiles sampled on morphological characteristics, by the Saskatchewan Soil Survey. The average exchangeable sodium percentage in the B horizons of the Calcareous, Orthic, and Eluviated Chernozems was 0.95, 1.3, and 2.6; and in the Bn horizons of the Solonetz, Solodized Solonetz, and Solod was 4.5, 9.4, and 4.0.Using the chemical criteria accepted by the National Soil Survey Committee of Canada for a n horizon (over 12% exchangeable sodium or more exchangeable sodium plus magnesium than calcium) only 28, 74, and 41% of the Solonetz, Solodized Solonetz, and Solod, as classified in the field, would remain in the Solonetzic Order. On the basis of exchangeable cations, 4% of the Orthic and 20% of the Eluviated Chernozems would fall within the Solonetzic Order because of high exchangeable magnesium.It is proposed that a Solonetzic B horizon on the basis of chemistry be one that contains more than 4% exchangeable sodium and has a ratio of exchangeable calcium to sodium of 10 or less, in order to exclude Chernozemic soils with high exchangeable magnesium from the Solonetzic Order.
FIXED AMMONIUM IN SOME SASKATCHEWAN SOILS
Authors: Hinman W. C.
Published: March 2010

Nitrogen, as fixed ammonium, occurred in the five profiles of arable soil of different texture which were examined. The amounts observed increased with increasing soil depth in four of the profiles. Total amounts found in the 4-ft profiles varied from 2600 to 4600 lb per acre and ranged from 7% of the total nitrogen in the surface soil to as much as 58% in the soil at the 4-ft depth.When the fixed ammonium nitrogen was subtracted from the total nitrogen the C:N ratios of these soils increased very sharply with depth, indicating that the subsoil organic matter was less rich in nitrogenous substances than was that of the surface soil.The clay fractions of the profiles were mineralogically similar and contained essentially the same amounts of fixed ammonium, approximately 2.4 meq ammonium per 100 g of clay. The silt fractions contained approximately 1.8 meq fixed ammonium per 100 g of silt. These fractions accounted for nearly all the fixed ammonium nitrogen observed except in the coarser-textured soils.Fixed ammonium and total nitrogen analysis of 25 paired samples of cultivated and virgin soil indicated that although the average total nitrogen had been reduced by one-third, there had been little or no effect on the amount of fixed ammonium N in the surface soil.
A PAINT SHAKER FOR SUSPENDING SOILS AND CLAYS
Authors: Clark J. S.
Published: March 2010

not available
AN APPROACH TO THE STUDY OF THE SULPHUR STATUS OF SOILS AND ITS APPLICATION TO SELECTED QUEBEC SOILS
Authors: Lowe L. E.
Published: March 2010

An approach to the study of the sulphur status of soils is described involving the application of one new procedure, and others developed previously, and is illustrated by results obtained on five Quebec soils. The sulphur in these soils was mainly organic in nature, the organic sulphates being the dominant organic sulphur fraction in the mineral soils, whereas the organic sulphate and carbon-bonded sulphur fractions were of similar magnitude in the organic soils. Two components of extractable sulphate were distinguished, namely easily soluble sulphate and adsorbed sulphate. In the mineral soils, the adsorbed sulphate was 26–50 times greater than the easily soluble sulphate.
SOIL PROFILE DEVELOPMENT IN SOME PEACE RIVER SOILS
Authors: Lavkulich L. M. , Pawluk S. , Odynsky W.
Published: March 2010

In the Peace River area of northern Alberta difficulty has been encountered in adopting the new Canadian classification scheme to a series of soils which occur under similar environmental conditions but still reflect varying degrees of profile development. The variation in profile development ranges from what appears to be almost Orthic Regosol to Orthic Grey Wooded. These soils are mapped as the Judah and Kathleen series by the Alberta Soil Survey. The analyses showed that the soils, under study, had a definite Bt horizon. The chemistry of the solum and clay mineral content were found to be similar to Grey Wooded soils in Alberta. Profile studies suggest erosion from the surface of these soils had occurred. The soils were classified as being both Chernozemic and Podzolic and belonging to three subgroups, namely Orthic Dark Grey, Dark Grey Wooded, and Orthic Grey Wooded.
THE NUTRIENT COMPOSITION OF HYBRID CORN AS INFLUENCED BY FERTILIZATION: II. THE PHOSPHORUS PERCENTAGE
Authors: Findlay W. I. , Fulton J. M.
Published: March 2010

Data are presented to show that leaf phosphorus percentages reflect the influence of nitrogen supply, soil type, and season as well as the phosphorus supply. Throughout a wide range of corn yields and associated phosphorus percentages no estimate of a critical phosphorus percentage was obtained.
EFFICIENCY OF VARIOUS SHAKERS IN THE PARTICLE-SIZE ANALYSIS OF SOILS
Authors: Lemieux G. J.
Published: March 2010

A review is made of the various types of shakers in use today in the particle-size analysis of soils with regard to their efficiency in speeding up dispersion with minimum abrasion of particles. Photomicrographs of soil particles submitted to the Bouyoucos drink mixer and a reciprocating shaker show the abrasive action of the former. Treatment with the Bouyoucos mixer strongly affected the proportion of the five commonly separated sand fractions as well as that of silt and clay. These observations seem to preclude the use of the Bouyoucos mixer for anything but routine analyses to determine broad textural classes.It is recommended that whenever accurate analyses are desired, shakers of the tumbling or reciprocating type be used. A simple, inexpensive reciprocating shaker, built out of a washing machine, is described.
EFFECT OF VARIOUS RATES OF LIMING AND FERTILIZATION ON CERTAIN CHEMICAL PROPERTIES OF A STRONGLY ACID SOIL AND ON THE ESTABLISHMENT, YIELD, BOTANICAL, AND CHEMICAL COMPOSITION OF A FORAGE MIXTURE
Authors: MacLeod L. B. , Calder F. W. , Bishop R. F. , MacEachern C. R.
Published: March 2010

In a field experiment, application of increasing rates of dolomitic limestone and 0-20-20 fertilizer to a strongly acid sandy loam produced marked changes in the chemical properties of the soil and in the composition and yield of a forage mixture grown thereon. The magnitude of the changes decreased as rates of limestone and fertilizer increased.Liming the soil caused decreases in exchangeable K and in Al extractable with N KCl. The latter change was particularly marked when soil pH was raised from 4.6 to 5.4.Legume species showed good establishment at all pH levels above 5.4 and relative sward density was highest at a pH of 6.2 to 6.6.Irrespective of fertilization rate dry-matter yields of forage were practically doubled by the 2.5-ton rate of limestone which changed soil pH from 4.6 to 5.4. There were also marked yield increases from fertilizer regardless of liming rate. The data further show that optimum yields resulted from liming to pH 6.0–6.5 and application of 400 lb per acre of 0-20-20.
CHARACTERISTICS AND GENESIS OF BRUNISOLIC SOILS OF NORTHERN ALBERTA
Authors: Pawluk S. , Lindsay J. D.
Published: March 2010

Exploratory surveys of the Wood Buffalo National Park in Northern Alberta revealed the presence of vast tracts of brunisolic soils. These soils are of common occurrence in the low plains area adjacent to Lake Clare.The brunisolic soils included in this study belong to the Brown Forest, Brown Wooded, and Acid Brown Wooded Great Soil Groups. All profiles were characterized with respect to their physical, chemical, and mineralogical properties. Special attention was directed to the Bf horizons where magnetic, amorphous (to X-ray) humus–iron micropellets were identified with the use of an electron microscope. The release of iron oxide from the weathering of iron-rich chlorites was also evident and is suggested as a mechanism by which the accretion of iron oxide to a pellet form could be explained. The possible genesis of these micropellets is fully discussed.
THE RELATION OF SOIL TEST VALUES TO FERTILIZER RESPONSE BY THE POTATO: III. EXCHANGEABLE POTASSIUM AND POTASSIUM FERTILIZER REQUIREMENTS
Authors: MacKay D. C. , MacEachern C. R. , Bishop R. F.
Published: March 2010

In experiments conducted at 46 locations over a 6-year period soil potassium levels ranged from 46 to 361 p.p.m. in exchangeable potassium and from 1.1 to 9.6% K saturation. The average yield of tubers on zero-K plots was 86.2% of the maximum (yield obtained from optimum K fertilization) and the zero-K plots produced less than 75% of the maximum at only two locations.Utilization of Bray's modified Mitscherlich equations indicated high variability in c1 values and poor correlation of relative yields (as percentages of the maxima) with soil test values. Expressing soil K as % K saturation provided only slightly better correlations than exchangeable K.The polynomial response equation relating absolute yields (bu/acre) with rates of applied potassium was highly significant, and near maximum yields of tubers were obtained at 150 lb/acre of K. When soils were grouped according to exchangeable K values into "high" (> 230 p.p.m.), "medium" (230–130 p.p.m.), and "low" (< 130 p.p.m.) classes, similar responses to application of K fertilizers were obtained for each. However, greater yields of tubers resulted on the higher soil test classes throughout the entire range of treatments.A highly significant linear depression in dry matter content resulted from potassium applications, with each 50 lb/acre increment of K depressing dry matter by 0.5%.
THE EVALUATION OF FOUR PRETREATMENTS USED IN PARTICLE-SIZE DISTRIBUTION ANALYSES
Authors: Protz R. , St. Arnaud R. J.
Published: March 2010

Four methods of soil pretreatment for particle-size distribution analyses compared using 10 Saskatchewan soils. Clay percentages, suspension pH values following shaking, and losses due to various treatments were used to evaluate the individual treatments. The high suspension PH required to obtain complete dispersion may not be achieved if excess acid is used to destroy lime carbonates prior to analysis. Lowering soil PH to 5.5 during pretreatment with dilute acid effectively removes free lime carbonates while still allowing complete dispersion.
EFFECTS OF FLOW VARIATIONS ON THE SALT CONTENT AND REACTION OF A MOUNTAIN CREEK
Authors: Korven H. C. , Wilcox J. C.
Published: March 2010

Water samples were taken and the stream flow measured at intervals during the summer, 1962, at several locations on a mountain stream and its tributaries which are a source of water for domestic and irrigation purposes for Summerland, B.C. Electrical conductivity and pH were determined for each sample and related to flow. There were highly significant negative correlations between the amount of water flowing past any given point in a stream and both conductivity and pH of the water at that point. Conductivity and pH showed high positive correlations. Considering the main stream on any one date, there was an increase in salt content of the water with a decrease in elevation. Storage reservoirs were beneficial because during the major portion of the irrigation season when storage water was being used, the increased flow meant a water supply of lower salt content and alkalinity than would be the case under normal stream flow.
THE DETERMINATION OF EXCHANGEABLE CATIONS AND CATION-EXCHANGE CAPACITY OF SOILS USING DILUTE NICKEL CHLORIDE
Authors: Baker Joseph , Burns W. T.
Published: March 2010

The use of nickel as a displacing ion in the determination of exchangeable cations and cation-exchange capacity was evaluated using several British Columbia soils. The values for exchangeable cations and cation-exchange capacity for the soils examined, using 0.25 normal neutral nickel chloride, were higher than those obtained by the ammonium acetate extraction method. For the most part, in samples examined, values were found to be more readily and consistently reproduced with the nickel chloride extractant. Dispersion of soil organic matter and silicate clay minerals was negligible, and the washing step involving ethanol has been eliminated.
USE OF SONIC VIBRATION FOR SEPARATION OF SOIL PARTICLES
Authors: Edwards A. P. , Bremner J. M.
Published: March 2010

not available
INFILTRATION CHARACTERISTICS OF A GUELPH LOAM SOIL FROM ANALYSIS OF HYDROLOGIC DATA
Authors: Percy M. J. , Ayers H. D. , Webber L. R.
Published: March 2010

Graphical analysis of 9 years of hydrologic data was used to derive 46 infiltration curves for 0.05-acre plots of Guelph loam. The rankings of infiltration rates under four management practices were: continuous corn < bare ground < oats after corn < corn after 2 years of hay. Mass infiltration decreased as soil moisture increased, and increased as the amount of rain during a storm increased.Mass infiltration tended to decrease with time on a plot planted continuously to corn for 9 years.
WATER QUALITY OF THE UPPER OLDMAN RIVER AND ITS TRIBUTARIES, ALBERTA
Authors: Lutwick L. E. , Chang P. C.
Published: March 2010

The concentrations of some chemical constituents of the stream waters depended upon the nature of the geological materials over which the streams were flowing. The quality of the water in the tributaries did not alter the quality of the water in the main stream.
RELATIONSHIP BETWEEN EVAPOTRANSPIRATION BY WHEAT AND THE STAGE OF CROP DEVELOPMENT, BELLANI-PLATE EVAPORATION, AND SOIL MOISTURE CONTENT
Authors: Ferguson W. S.
Published: March 2010

Mean weekly evapotranspiration by spring wheat at Brandon, Man. (1955–1959) was dependent on the stage of development of the crop. It increased from 0.70 in. per week at the 3-leaf stage to 1.45 in. per week at the flowering stage and decreased to 0.60 in. per week as the crop reached maturity. Evapotranspiration was correlated positively with Bellani-plate evaporation when the soil was moist to the surface and correlated negatively when the surface soil was dry, but total soil moisture was greater than 50% of field capacity. When the soil moisture was less than 50% of field capacity evapotranspiration was not correlated with Bellani-plate evaporation. Evapotranspiration was correlated positively with total soil moisture plus rainfall. This emphasizes the importance of moisture stress in limiting evapotranspiration in a semi-arid region.
RELATIONSHIP OF WATER TABLE AND Eh TO PROPERTIES OF THREE CLAY SOILS IN THE OTTAWA VALLEY
Authors: McKeague J. A.
Published: March 2010

Properties of three clay soils of differing wetness were related to water table levels and redox conditions. High Eh values and low water table prevailed throughout 2 years at the Wendover site. The soil, an Orthic Acid Brown Forest, was weakly developed with a thin Ah horizon and a Bm horizon in which vermiculite apparently formed from mica. At the level Bearbrook site, the water table fluctuated between the surface and 8 ft, the solum varied in moisture from saturation to extreme dryness, and Eh values fluctuated between 800 mv and −150 mv. A thin but distinct Aeg horizon of low base saturation underlay the H horizon. A marked accumulation of free iron oxide occurred in the strongly mottled Bfg horizon. Clay mineralogy changed from largely vermiculite in the Aeg horizon to montmorillonite and illite in the underlying horizons of this Orthic Gleysol. The water table was usually within 2 ft of the surface at the Laplaine site. This Peaty Rego Gleysol had an H horizon underlaid by olive-gray clay in which properties changed little with depth. Horizon differentiation appeared to be favored by wide seasonal fluctuations in moisture status and redox potentials.
THE RELATIONSHIP OF PATTERN AND GRADIENT OF SLOPES TO SOIL TYPE
Authors: Acton D. F.
Published: March 2010

Three glacial landforms (hummocky moraine, linear disintegration ridge, and washboard ridge) resulting from ice disintegration were studied to determine the relationship of the type of landform to the distribution of soil members or series. A close relationship was observed between a soil member and the nature of the slope segment on which it occurred. Calcareous Dark Brown soils were observed on the uppermost convex portion of the slope on gradients usually greater than 8%; Orthic Dark Brown soils on simple intermediate slopes or 5–8% gradient; Eluviated Dark Brown soils on slightly concave footslopes of 1–3% gradient; Rego Dark Brown wherever 3–5% slopes extended from the margin of depressions; and Gleysolic soils in the concave depressions. The extent of the soil members was found to be a function of the extent of the individual slope segment present in the landform. Orthic Dark Brown soils predominated, to approximately the same extent, on all landforms. Gleysolic soils were extensive in hummocky moraines whereas Eluviated and Calcareous Dark Brown soils were more extensive on ridged landforms, particularly on linear disintegration ridges. Rego Dark Brown soils were most extensive on washboard ridges.
SOIL TEMPERATURE CONTROL SYSTEM FOR FIELD PLOTS
Authors: Mack A. R. , Evans W. A.
Published: March 2010

not available
TIME OF SAMPLING AFTER AN IRRIGATION TO DETERMINE FIELD CAPACITY OF SOIL
Authors: Wilcox J. C.
Published: March 2010

Drainage curves following irrigation were determined at six depths in eight soils having unrestricted drainage but varying widely in soil texture. The field capacities were determined under relatively high rates of evapotranspiration. The time after irrigation that it was necessary to wait before sampling the soil, to determine field capacity, was also determined. A high positive correlation was obtained between the log of field capacity in inches and the log of time after irrigation at which to sample the soil. The time varied from about 0.5 day with 1.5 in. field capacity to 4.0 days with 35 in. From the curves of soil moisture content versus time, the errors caused by sampling too soon or too late were determined. The percentage error (i.e. percent of field capacity) increased with an increase in the error in time of sampling; it decreased with an increase in field capacity in inches; and it was greater when sampling was too soon than when it was too late.
ORGANIC PHOSPHORUS IN SOME NEW BRUNSWICK SOILS
Authors: MacLean A. A.
Published: March 2010

Levels of organic phosphorus in 12 New Brunswick soils and influence of cultivation were investigated.Organic phosphorus levels by the extraction method of Mehta et al. ranged from 161 to 403 μg/g and from 203 to 528 μg/g by the Saunders and Williams ignition method. Mean values for all soils by these methods were 291 and 365 μg/g respectively, which were equivalent to 34.8 and 43.7% of the total soil phosphorus.Organic phosphorus was lower on intensively cultivated sites than on adjacent areas that had been in sod for extended periods. The decline was equivalent to 14%.
A LABORATORY STUDY OF GLEYING
Authors: McKeague J. A.
Published: March 2010

Columns of different soil materials with ground leaves at the surface were maintained for 18 months with the water table continuously above the surface, or fluctuating between the surface and 15 cm. Redox potentials, colors, and extractable iron were determined. The effects of temperature and of organic matter on the rate of change of Eh were studied with flooded soils in test tubes.The rate and degree of development of dull colors and mottling in the soil columns was influenced greatly by the nature of the soil material. Reduction effected marked increases in acetic acid extractable iron from all of the soil materials. Low redox potentials developed rapidly at room temperature in flooded soils containing appreciable amounts of organic matter. Eh values below 0 mv developed slowly in soils at 1 °C and at room temperature in some soils that were almost devoid of organic matter. Release of Fe+2 from ferrous minerals was thought to account for these low Eh values.
INFLUENCE OF SOIL TEXTURE, DEPTH OF SOIL MOISTURE STORAGE, AND RAINFALL DISTRIBUTION ON WHEAT YIELDS IN SOUTHWESTERN SASKATCHEWAN
Authors: Lehane J. J. , Staple W. J.
Published: March 2010

In dry seasons wheat yields were higher on clay than on loam and sandy loam soils for equal amounts of moisture used. In wetter seasons, yields were higher on both clay and loam than on sandy loam.Grain yields were little influenced by the amount of moisture stored in the 0- to 6-in. and 6- to 12-in. layers at seedtime, but they were increased markedly by the moisture stored below the 12-in. depth.Multiple regression equations taking into account rainfall distribution during the season gave better estimates of yield than did equations using total seasonal rainfall only. Rainfall received during June and July and available moisture stored below 12-in. depth were important factors influencing grain yield on all soils.
THE USE OF A SOLENOID WATER VALVE IN AN ELECTRODIALYSIS SYSTEM
Authors: Dormaar J. F. , Tyrrell C.
Published: March 2010

not available
STUDIES ON METHODS FOR THE DETERMINATION OF SUGARS AND URONIC ACIDS IN SOILS
Authors: Gupta Umesh C. , Sowden F. J.
Published: March 2010

not available
CARBOXYL AND PHENOLIC HYDROXYL GROUPS IN SOME ORGANIC SOILS AND THEIR RELATION TO THE DEGREE OF HUMIFICATION
Authors: Schnitzer M. , Desjardins J. G.
Published: March 2010

The degree of humification of 17 organic soil samples was determined by the pyrophosphate test of Dawson as described by MacLean et al. (5) and the colorimetric method of Kaila (4). The latter procedure, although more laborious, was preferred because of good replication and exclusion of the personal judgment of an observer.Treatment with HCl–HF solution resulted in a significant reduction in the ash content of most samples; concomitant losses of organic matter were less than 5%. The main effect of the HCl–HF treatment was to free carboxyl groups. By contrast, phenolic hydroxyl groups remained apparently unaffected. Carboxyls appeared to be the most reactive groups in these organic soil samples. Infrared spectra of untreated peats and of mucky peats exhibited bands at 1720 cm−1, indicative of the presence of free carboxylic acid groups. These bands were absent in the spectra of mucks. After the acid treatment, however, infrared spectra of mucks showed new strong bands at 1720 cm−1 and decreased absorption at 1625 cm−1, apparently due to the conversion of carboxylate to carboxylic acid groups.The total carbon, hydrogen, sulphur, and oxygen contents were similar for all samples, but peats and mucky peats tended to contain less total nitrogen than mucks.
SULPHUR FRACTIONS OF SELECTED ALBERTA SOIL PROFILES OF THE CHERNOZEMIC AND PODZOLIC ORDERS
Authors: Lowe L. E.
Published: March 2010

Total sulphur, carbon-bonded sulphur, HI-reducible sulphur, easily soluble sulphate, adsorbed sulphate, and sulphate associated with calcium carbonate were determined on seven Grey Wooded profiles and eight Chernozemic profiles, the latter including soils from the Brown, Dark Brown, Thin Black, and Black soil zones of Alberta.A clear dichotomy was observed between the Chernozemic and Grey Wooded (Podzolic) profiles. Organic forms of sulphur predominated in all surface and B horizons, although inorganic sulphate reached high levels in C horizons of some Chernozemic profiles. HI-reducible sulphur accounted for 63% and 71% of the total sulphur of Chernozemic Ah and Bm horizons, but only 33% and 48% of the total sulphur of Grey Wooded L-H and Bt horizons. N:HI-reducible sulphur ratios were much wider in the surface and B horizons of the Grey Wooded profiles than in the Chernozems. Carbon-bonded sulphur decreased with depth in all profiles, representing 17% and 9% of the total sulphur in the Chernozemic Ah and Bm, and 26% and 15% in the Grey Wooded L-H and Bt respectively. Sulphated polysaccharides were isolated from all surface horizons, but in no case accounted for more than 2% of the total sulphur. An inert sulphur fraction, resistant to strong oxidizing and reducing agents, was detected in residues of four samples subjected to exhaustive extraction with hot acid and alkali. This fraction accounted for 2–44% of the total sulphur, the highest value being observed in a Grey Wooded L-H sample.
TRACE ELEMENTS IN SOME NEW BRUNSWICK SOILS
Authors: Presant E. W. , Tupper W. M.
Published: March 2010

A trace element study was carried out on 71 well-drained Podzol soil profiles from the Bathurst region of northeastern New Brunswick. Of these profiles 18 were selected from soils located above sulphide deposits; the other 53 were chosen randomly from areas not underlaid by sulphide-rich rocks. Lead, copper, zinc, iron, manganese, arsenic, antimony, silver, and tin were the elements studied.Lead, silver, and manganese showed definite tendencies to accumulate in the surface L–H horizons. Tin was the only element to consistently show concentrations in the Ae horizons. Arsenic, iron, and lead have accumulated in the B horizons of most profiles. The mean amounts of trace elements for all horizons of the profiles overlying sulphide deposits were higher than similar mean values for profiles above non-mineralized bedrock.
EFFECT OF SOIL TEMPERATURE AND MOISTURE ON YIELD AND NUTRIENT UPTAKE BY BARLEY
Authors: Mack A. R.
Published: March 2010

In a field experiment yields of barley were lower, regardless of moisture, when the mean minimal soil temperature was near 27 °C than near 9 °C or 18 °C. The highest yields were obtained at 18 °C. Application of fertilizer increased final yields and uptake of N, P, and K at 9 °C and 18 °C but not at 27 °C. At 9 °C and 18 °C response to added fertilizer occurred as the moisture content of the soil was raised from near the wilting point to field capacity. During the early stages of growth an increase either in temperature or moisture increased the uptake of N, P, and K. Percentage P in the plant material during early growth was related to yield near heading stage when soil temperature conditions were considered. The protein content of the grain was increased at the higher soil temperature for all moisture conditions.
INFLUENCE DU pH ET DES ELEMENTS FERTILISANTS SUR L'INTOXICATION MANGANIQUE DE LA POMME DE TERRE
Authors: Ouellette G. J. , Généreux Henri
Published: March 2010

not available
MINERALIZATION OF NITROGEN IN SOME FRASER VALLEY SOILS AS AFFECTED BY LIMING
Authors: Gardner E. H. , Derics I. A. , Basaraba J.
Published: March 2010

not available
Evaluation of the concentration the cadmium, cupper, iron, manganese, nickel and zinc in Anomalocardia brasiliana (Gmelin, 1791) distributed in mangrove areas of São Francisco do Conde and Madre de Deus, Recôncavo Baiano, BA
Authors: Jesus Taise Bomfim de , Fernandez L. G. , Queiroz A. F. de S.
Published: March 2010

Cadmium (Cd), cupper (Cu), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn) concentrations had been investigated in specimens of the mollusc bivalve Anomalocardia brasiliana (Gmelin, 1791), distributed at nine stations situated in mangroves zones, located at the Baía de Todos os Santos, Bahia, Brazil. Collection sites were selected based on the existence of antropic sources. The analyses had been carried through the atomic absorption spectrometry after drying and digestion of the sample. The concentrations of Cd, Fe, Mn and Ni had differed statistical (p < 0.05) at the different areas. The sites with strong industry influence, Coqueiro Grande at the northeast part of the Baía de Todos os Santos, and Fazenda Cajaíba located at the northern part, had presented the highest concentrations for metals in study. Despite the high concentrations found none of the analysed metals were above the limit established of the Brazilian legislation for human consumption.
High‐Throughput Flow Cytometry
Authors: Sklar Larry A. , Simons Peter C. , Waller Anna , Biggs Sean M. , Young Susan M. , Olah Marius , Bologa Cristian , Oprea Tudor I. , Prossnitz Eric R. , Edwards Bruce S.
Published: March 2010

This article describes the creation of a discovery team in an academic environment. The team is specifically structured to perform four integrated activities: characterizing membrane protein, formatting the materials for analysis of cell physiology and molecular interactions, performing screens of small‐molecule activity on a novel high‐throughput flow cytometric instrument platform, and integrating virtual screening with activity screening. These activities improve the overall efficiency of the discovery process.
CombiningNMRSpectral Information with Associated Structural Features to form Computationally Nonintensive, Rugged, and Objective Models of Biological Activity
Authors: Beger Richard D. , Buzatu Dan A. , Wilkes Jon G.
Published: March 2010

This article focuses on an alternative strategy for model building known as quantitative spectrometric data–activity relationships (QSDARs). Three‐dimensional QSDAR modeling is a complementary technique that has widespread application to many informatics challenges. It provides computational model developers a sensitive, alternate perspective on biological and toxicological properties.
Age of Regulation
Authors: Weinberg Sandy , Whartenby Gerald J.
Published: March 2010

There are three underlying precepts that together provide a foundation for and an understanding of all the myriad of FDA procedures: (1) proximal causality, (2) risk assessment, and (3) self‐regulation. Part 11 of section 21 of the Code of Federal Regulations (CFR) deals with electronic records, with the systems that produce those records in automated laboratories, clinical testing environments, and manufacturing facilities, and with the electronic approvals and signatures of those records. This article focuses on the history of the FDA, 21 CFR Part 11, and six steps of conducting risk assessment.
Simultaneous Screening of Multiple Cell Lines Using the
Cell
Card
System
Authors: Beske Oren E.
Published: March 2010

The CellCard system provides a novel platform for cell‐based assays. At the core of the platform are encoded particles referred to as CellCards. By growing individual cell types on CellCards with unique codes, the platform enables multiple cell types to be assayed simultaneously in 96‐well format. This article describes the CellCard technology and how it can be applied to the determination of cell‐type selectivity of bioactive molecules.
ProteinX‐Ray Crystallography in Drug Discovery
Authors: Nollert Peter , Feese Michael D. , Staker Bart L. , Kim Hidong
Published: March 2010

Protein X‐ray crystallography has affected drug discovery in (a) the identification of new drug targets, (b) the understanding of molecular target mechanisms, and (c) the discovery of new lead compounds. The integration of protein X‐ray crystallography into the early discovery process by joining it with chemical synthesis and assaying has become a very effective tool for lead optimization. This article aims to familiarize scientists with X‐ray protein crystallographic techniques and their exemplified application for the purpose of drug discovery.
Biological and Chemistry Assays Available During Drug Discovery And Developability Assessment
Authors: Lakings Duane B.
Published: March 2010

The discovery and development of a novel therapeutic agent requires scientific expertise from a number of different disciplines, an enormous amount of time, and money. Research studies conducted during the discovery phase in in vitro systems and in animal models can determine whether a discovery lead or group of leads. This article discusses some of the in vitro and in vivo assays employed by researchers during the drug discovery and developability assessment phases of the discovery and development processes.
High‐Throughput Screening: Evolution of Technology and Methods
Authors: Banks Martyn N. , Cacace Angela M. , O'Connell Jonathan , Houston John G.
Published: March 2010

High‐throughput screening (HTS) can be defined as a process by which hundreds of thousands to millions of compounds are tested for activity against disease targets of interest with the goal of identifying truly active, progressible “hits”. Over the last 20 years high‐throughput screening (HTS) has become a successful, reliable component of the drug discovery process. This article focuses on the variety of screening plate formats and the implications of their usage on the supporting technologies and assay designs.
Coupled Luminescent Methods in Drug Discovery: 3‐min Assays for Cytotoxicity and Phosphatase Activity
Authors: Corey Michael J. , Kinders Robert J.
Published: March 2010

Coupled luminescent technology has wide potential in drug discovery process. In comparison of fluorescent assay, coupled luminescent assays offer very rapid and sensitive readouts with minimal sample and reagent usage. However, there are idiosyncrasies and limitations inherent to the method, many of which are associated with the presence of multiple catalytic activities. This article focuses on the role of DeathTRAK and PhosTRAK assay methods in drug discovery.