bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPARATIVE SURVIVAL AND DECOMPOSING ABILITY OF FOUR FUNGI ISOLATED FROM LEAF LITTER AT LOW TEMPERATURES
Authors: IVARSON K. C.
Published: March 2010

The survival and decomposing ability of the four dominant fungi found in low-temperature decomposing leaf litter was studied over a 46-mo period, at temperatures ranging from 1 C to room temperature. A Rhizoctonia sp. by itself and in association with the three other fungi disappeared. When alone it brought about no decomposition. Over the temperature range a Penicillium sp. that appeared to be a member of the Penicillium terrestre series showed strong survival properties in association with the other fungi, and by itself decomposed about the same amount of litter as the natural microbial flora of the unaltered litter, indicating that under natural conditions and at temperatures above 1 C this fungus is an important colonizer and decomposer of organic matter. Mucor spinescens alone and in association survived at room temperature and 10 C, but was absent at 4 and 1 C. By itself it decomposed a small amount of litter. The most abundant species, Chrysosporium pannorum (50% of all isolates at cold temperatures), a cellulolytic fungus, was not able to survive in litter in the absence of the other fungi. In their presence, it not only survived but increased in number as temperature decreased. The facts that pH changes and litter extract did not affect its growth suggest that C. pannorum does not possess the ability to be a pioneer colonist, and it is only after associated fungi begin the initial breakdown and perhaps supply easily available energy sources or growth factors that C. pannorum is able to take part in the decomposition process and survive. Thus, as temperature decreases, there is perhaps less competition for this cold-tolerant fungus, and its role in the decomposition process increases.
GENETIC HISTORY OF TWO WELL-DRAINED SUBALPINE SOILS FORMED ON COMPLEX PARENT MATERIALS
Authors: SINGER MICHAEL , UGOLINI F. C.
Published: March 2010

Two well-drained soils formed in the subalpine zone of the Washington Cascades from the same complex parent material and environment exhibit contrasting morphologies due to the vegetation. One of the soils, presently unforested, exhibits in its morphology the influence of three ash falls and a complex vegetational history. The horizon sequence and properties fit the Lithic Regosol criteria of the Canadian classification system. The second soil, formed on the same parent materials but under forest vegetation, exhibits properties of an orthic Ferro-Humic Podzol. These pedons exemplify the complex nature of soils whose classification has previously been oversimplified as steep, rocky soils or lithosols.
SEASONAL AND VERTICAL DISTRIBUTION OF SOIL FAUNA IN A THINNED AND UREA-FERTILIZED DOUGLAS FIR FOREST
Authors: MARSHALL V. G.
Published: March 2010

Ecological studies on soil nematodes, enchytraeids, collembolans and mites in a 1948 Pseudotsuga menziesii plantation at Shawnigan, British Columbia were made from March 1971 to March 1972. The plantation was thinned to 1,900 stems/ha and urea was applied at 0, 224 and 448 kg N/ha just before faunal sampling. Monthly samples were extracted in high-gradient apparatus, Murphy split funnels and simple wet funnels. Fifty-two and 53% of collembolans and mites, respectively, occurred in the top 5.3 cm of the 17.5-cm soil profile studied. The Pearson and Hartley power function test indicated that for intramonth sampling to show statistical significance of treatment, at least 10 samples per treatment would be required for any of the groups under experimental conditions similar to the one reported here. Collembolans and mites exhibited significant downward seasonal distribution, and urea treatment accentuated this phenomenon for all four groups, suggesting that sampling below 6 cm would be required to observe the full impact of urea fertilization on the soil fauna. Except for enchytraeids, seasonal population fluctuation contrasted with the generally observed pattern in temperate regions of spring and fall peaks and showed increases through the spring, culminating in summer and autumn maxima. Urea fertilization increased annual mean population of nematodes by 1.41 and 2.51 times the control for 224 and 448 kg N/ha, respectively, and decreased enchytraeids by 0.52 and 0.28 times the control for the same two fertilizer rates; collembolans and mites were not significantly affected.
EFFECTS OF pH AND NITRIFIER POPULATION ON NITRIFICATION OF BAND-APPLIED AND HOMOGENEOUSLY MIXED UREA NITROGEN IN SOILS
Authors: PANG P. C. , CHO C. M. , HEDLIN R. A.
Published: March 2010

Two soils, Keld silty clay loam (pH 5.4) and Wellwood clay loam (pH 6.6), were used to investigate the effects of modifying soil pH upon the nitrification of band-applied urea at 20 C. The pH of the Keld soil was adjusted to 6.5 and 7.3 with Ca (OH)2, whereas the Wellwood soil was adjusted to 5.6 with H2SO4. In addition, nitrification of nitrogen in a homogeneously mixed soil–urea suspension at 20 C was studied using the two soils mentioned and also Morton very fine sandy loam (pH 8.2). There were marked differences in the rate of oxidation of NH4 between the natural Keld and acidified Wellwood soils at comparable soil pH values. The oxidation was found to be very slow in the Keld soil at all pH values and no appreciable nitrite was formed. In the Wellwood soil, nitrification was more rapid and was accompanied by nitrite formation. However, the rate of oxidation was temporarily retarded by decreasing the pH of the Wellwood soil, but the oxidation of band-applied urea in the Keld soil remained unchanged with modified pH of 6.5 and 7.3. Increase in nitrification and nitrate accumulation occurred when the limed Keld soils (pH 7.3) was inoculated with Nitrosomonas europaea. Soil suspension studies confirmed that the difference in nitrifying capacity among the soils was related to the initial nitrifier numbers whose activities were affected by the initial soil pH.
EFFECTS OF NITROGEN CONCENTRATION ON THE TRANSFORMATION OF BAND-APPLIED NITROGEN FERTILIZERS
Authors: PANG P. C. , CHO C. M. , HEDLIN R. A.
Published: March 2010

The concentration of the ammonium form of N (NH4+ + NH3) at the fertilizer zone in a neutral Wellwood soil (pH 6.6) banded with (NH2)2CO and NH4OH had an effect on nitrite accumulation. Nitrite accumulated when (NH2)2CO and NH4OH were banded at rates of 800 and 200 kg N/ha (on an area basis), but no nitrite accumulated at 100 kg N/ha. With urea, the lowest rate at which nitrite accumulated (200 kg N/ha) corresponded to an ammonium concentration near the fertilizer band of 750 ppm after 1 wk incubation, and 400 ppm N after 2 wk incubation. At a rate of 100 kg N/ha where no nitrite accumulated, the concentration of ammonium form was 500 ppm N and 250 ppm N at 1 and 2 wk, respectively. Irrespective of the rate of N, only a trace of nitrite accumulated when soil was banded with (NH4)2SO4 and incubated.
IMPROVEMENTS IN SAMPLING, STORING AND ANALYSIS OF SOIL AIR FOR GAS CHROMATOGRAPHY
Authors: BUNTTNG B. T. , CAMPBELL J. A.
Published: March 2010

not available
RESIDUES OF PARAQUAT IN AN ORCHARD SOIL
Authors: KHAN S. U. , MARRIAGE P. B. , SAIDAK W. J.
Published: March 2010

not available
CONSECUTIVE STEADY STATE REACTIONS OF UREA, AMMONIUM AND NITRITE NITROGEN IN SOIL
Authors: ARDAKANI M. S. , VOLZ M. G. , McLAREN A. D.
Published: March 2010

Previously developed mathematical models based on first and zero order sequential transformations of urea–nitrogen to nitrate by soil urease and microorganisms, based on Michaelis–Menten-type kinetics, were examined in a laboratory soil column with continuous flow. Comparison with data show that the models describe adequately concentration profiles of urea, NH4+, NO2− and NO3−. Apparent rate constants for urea hydrolysis and for NH4+ and NO2− oxidation increased with duration of flow. These increases in rate constants are attributable to microbial growth. A microbial profile developed in the column and was characterized by a decrease in population densities with depth.
RELATIONSHIPS BETWEEN NITRATE IN SUMMER-FALLOWED SURFACE SOIL AND SOME ENVIRONMENTAL VARIABLES
Authors: CAMPBELL C. A. , BIEDERBECK V. O. , HINMAN W. C.
Published: March 2010

Multiple regression was used to quantify the relationships between NO3 in surface soil versus several selected environmental variables. Measurements were made on summer-fallowed Wood Mountain loam in the field. The temperatures and moisture conditions measured during one growing season were simulated in the laboratory using three soils. The most important factor influencing NO3 change was wetting and drying. The latter's effect was dependent on the soil moisture content just before the change occurred and/or the temperature during the period of change. Nitrification accounted for 12% of the increases in NO3 in the top 2.5 cm of soil; 88% of the increase resulted from upward movement of NO3-salts into the surface layer of soil as a result of evaporation. Of the NO3 produced by nitrification in the Wood Mountain loam, about 17.4% was credited to temperature effects. Thus only about 2.1% of the NO3 increase in the top 2.5 cm of soil in the field was due to temperature. In the simulation study, 19 C appeared to be a critical temperature above which the rate of nitrification was sufficient to counterbalance NO3 losses resulting from leaching and/or denitrification. The effect of moisture change on NO3 change appeared to be directly proportional to the total C and total N content of the three soils.
SALT STATUS OF SOME SOILS OF THE SLAVE RIVER LOWLANDS IN CANADA'S NORTHWEST TERRITORIES
Authors: PRINGLE W. L. , HENNIG A. M. F. , CAIRNS R. R. , SIEMENS B.
Published: March 2010

As part of a study to determine the agricultural potential of 833,000 ha of land in Canada's Northwest Territories along the Slave River it was found that the poorly drained soils of the Grand Detour complex were saline to varying degrees. It is estimated that about 80,000 ha of Rego Humic Gleysols have electrical conductivities exceeding 4 mmhos/cm in the surface 20 cm. Sampling of soils and water indicated that sodium was the prevalent cation and that it was present in some soils in amounts sufficient to limit agricultural production. It was shown that surface disturbance, as in land preparation for cropping, increased salinity in the surface layers of soil thus reducing the potentially arable area to those soil types in which concentrations of salts are much lower. Results of this study show that salinity problems are not confined to warmer areas of the world but may also be a factor in restricting agricultural expansion into the subarctic.
LEAD-210 ASSAY IN SOIL AND PLANT MATERIAL USING CERENKOV RADIATION
Authors: KARAMANOS R. E. , BETTANY J. R. , RENNIE D. A.
Published: March 2010

Cerenkov radiation counting was found to be an excellent method of radioassay of 210Pb in aqueous extracts of soils and acid digests of plant material. The use of polyethylene vials and a wavelength shifter 7-amino-1,3-naphthalene-disulfonic acid greatly improved the counting efficiency. Color quenching was the main factor in lowering counting efficiency but could be corrected using the channels ratio method. Extracts of soils having high organic matter contents showed severe color quenching. Pretreatment of these extracts with 30% H2O2 greatly increased the counting efficiency.
ORGANIC AND INORGANIC P CONTENT, MOVEMENT AND MINERALIZATION OF P IN SOIL BENEATH A FEEDLOT
Authors: CAMPBELL L. B. , RACZ G. J.
Published: March 2010

Greater amounts of 0.5 M NaHCO3 and water-extractable P were found in soil beneath a cattle feedlot located on an alkaline sandy soil than in soil in an adjacent non-manured field. The 0.5 M NaHCO3-extractable P contents of the feedlot soil samples were greater than for the adjacent field to a depth of 120–150 cm, suggesting that P from the manure had moved to this depth. Water extracted very little P from all field samples and the feedlot samples obtained below 120 cm. Concentration of total P in the feedlot soil was usually greater than in the corresponding field soil. The field soil contained more organic P than the feedlot soil at depths of 0–90 cm. Organic P concentrations at the 0 to 15-cm depths were 268 and 56 ppm for the field and feedlot sites, respectively. The organic C:N:P ratios for the 0 to 15-cm feedlot and field samples were 214:18:1 and 132:8.7:1, respectively. Mineralization of organic P in laboratory experiments was greater in flooded soils than in soils maintained at field capacity. Rates of mineralization were greater for manured than for non-manured samples. Organic and inorganic P moved at about equal rates in soil treated with manure extract. Rates of movement of both decreased with increasing sample depth in the feedlot soil. The feedlot soil below 30 cm and the field soils exhibited a high potential for inorganic and organic P fixation. Organic and inorganic P applied as manure extract moved faster than an equivalent concentration of P as KH2PO4.
FRACTIONATION OF SOIL AND 15N NITROGEN TO SEPARATE THE ORGANIC AND CLAY INTERACTIONS OF IMMOBILIZED N
Authors: McGILL W. B. , PAUL E. A.
Published: March 2010

Labelled 15N was added to two soils in cylinders in the field, and allowed to equilibrate for two summers of crop growth. The labelled soils were fractionated to provide information on the effect of organic and inorganic colloids on the stabilization of immobilized, 15N. Organic materials removed by 0.5 N NaOH without pretreatment contained more 15N than those extracted by the same reagent following decalcification and removal of sesquioxides with dithionite and HCl. Both extracts had similar amino acid (contents) and similar degrees of hydrolability. A fractionation system using an initial 0.1 M NaOH–0.1 M Na4P2O7 extraction followed by sonication and peptization in H2O yielded a humic acid fraction and a sedimentation fraction (< 0.04 μm) which differed markedly in degree of hydrolyzability, 15N content and amino acid-N content. The N associated with inorganic colloids < 0.04 μm, and that remaining in solution after the removal of larger particles accounted for 50% of the amino acid-N in a clay soil, and 40% in a fine sandy loam soil. Removal of sesquioxides followed by a second 0.5 N NaOH extraction reduced the N content of the colloidal size fractions of both soils, indicating that amorphous iron and aluminum compounds on the surface of clays are probably the active agents in bonding organic N to inorganic colloids. It is suggested that the nonhydrolytic technique, based largely on dispersion of the inorganic–organic colloids and analyses of the sediment, could be used to interpret the fate of microbiologically immobilized N compounds in the soil. Materials removed by 0.1 M Na4P2O7 were associated with polyvalent cations in the soil. Materials such as cytoplasmic constituents, released from the biomass during ultrasonic vibration or as lytic products would be expected to be adsorbed to inorganic colloids. They should be concentrated in the < 0.04 μm-size fraction. Cell wall and other particulate debris with a faster setting velocity would be expected to appear in larger-sized sedimentation fractions.
SOIL BACTERIAL CHANGES AS AFFECTED BY GROWING SEASON WEATHER CONDITIONS: A FIELD AND LABORATORY STUDY
Authors: CAMPBELL C. A. , BIEDERBECK V. O.
Published: March 2010

During the 1972 and 1974 growing season, soil bacteria, actinomycetes, moisture and temperature in the top 15 cm of a Wood Mountain loam were monitored regularly under sheltered and unsheltered summer-fallow and cropped conditions. The 1972 temperatures and rainfall were later simulated in the laboratory and their effects on the bacterial population in the Wood Mountain loam, a Sceptre heavy clay, and a Melfort silty clay loam determined. Multiple regression was used to quantify the relationships between the different microbial populations and several selected environmental variables. Microbial change was generally directly proportional to moisture change, the latter being the main factor influencing response. The effect of moisture change was usually dependent on the temperature and/or the initial moisture content prior to the change. Soil microbial populations increased in response to both increases and decreases in temperature. The inverse relationship with temperature appeared to be the result of the dry soil surface being wetted by dew which accompanied low night temperatures. Microbial responses were greater in the top 2.5 cm than in the 2.5- to 15-cm segment. Bacteria and actinomycetes responded to environmental stimuli in a similar manner but the response of bacteria was usually greater than that of actinomycetes. The bacteria: actinomycetes ratio was 3:1 in the top 2.5 cm but only 1.3:1 in the 2.5- to 15-cm segment. Cropping the soil had no effect on microbial numbers. In the laboratory study, denitrifier response was more closely related to rainfall than were bacterial or actinomycetal response. Denitrifier response was greatest in the clay and least in the loam.
EXTRACTABLE PHOSPHORUS IN SURFACE AND SUBSURFACE LAYERS OF STE. ROSALIE AND ST. BLAISE SOIL SERIES IN QUEBEC
Authors: BEAUCHAMP E. G. , MacMILLAN K. , HAMILTON H. A.
Published: March 2010

The relationship between extractable P and soil characteristics including pH, clay content (CLAY), cation exchange capacity (CEC), organic matter content (OM), and phosphorus retention (PRET) was determined using stepwise multiple regression analysis. Similarly, the influence of pH, CLAY, CEC, OM and PRET on the relationship between extractable P and relative yield (Yo/Yp) of young corn plants in the greenhouse was determined. Surface (0- to 20-cm) and subsurface (20- to 40-cm) layers from two soil series (St. Blaise and Ste. Rosalie) were collected from farm fields in the region south of Montreal. Twenty-eight sites of the St. Blaise series and 25 sites of the Ste. Rosalie series were sampled from fields of which the majority were in cultivation for 100–200 yr. Three P extractants were used: Bray 1 (P1) (0.03 N NH4F, 0.025 N HCl), Bray 2 (P2) (0.03 N NH4F, 0.1 N HCl) and 0.5 M NaHCO3 (P3). Extractable P by all three extractants was negatively correlated with pH of the St. Blaise surface soils. However, extractable P by the P2 extractant was positively correlated with pH of the Ste. Rosalie surface soils. Although significant, the R2 values for these relationships were low, ranging from 0.15 to 0.17 for the surface soils. Extractable P was related, to variable extents, to one or more of pH, PRET, OM and CEC of the subsurface soils depending on the soil series and P extractant in an unexplainable manner. However, the R2 values were generally much higher for the subsurface than surface soils suggesting that extractable P in subsurface soils was more closely related to the measured soil characteristics. There was no relationship between extractable P with any extractant and CLAY for either series. The highest correlation between relative yield (Yo/Yp) and extractable P occurred with P3 for the surface soils of both series. None of the soil characteristics was included with P3 in the regressions with the surface soils. PRET was included along with P2 in the regression with Yo/Yp for the St. Blaise surface soils, whereas a P × CLAY interaction term occurred with the P1 and P2 extractants for the Ste. Rosalie surface soils. A linear relationship was obtained between Yo/Yp and P1 or P3 for the Ste. Rosalie surface soils and P2 for the St. Blaise surface soils. A curvilinear relationship was obtained with P1 or P3 for the St. Blaise surface soils and with P2 for the Ste. Rosalie surface soils. Extractable P was not included as an independent variable in any of the regressions with Yo/Yp as the dependent variable for the subsurface soils. This suggests that extractable P with any of the extractants used in this study does not reflect the availability of P in subsurface soils.
THE NATURE OF MERCURY IN CHERNOZEMIC AND LUVISOLIC SOILS IN ALBERTA
Authors: DUDAS M. J. , PAWLUK S.
Published: March 2010

Contents of mercury in surface soil horizons of Chernozemic soils from Alberta were considerably lower than contents in respective C horizons. For eluviated soils, highest contents of mercury were found in B horizons, with lowest levels in A horizons. Results for content of mercury in particle-size separates together with profile distribution patterns for the element suggested that a significant portion of the mercury in surface mineral horizons was mobilized to the atmosphere. Pyrolysis studies indicated that the dominant form of mercury in the soils consisted of organically bound compounds.
A DURABLE AND INEXPENSIVE SAMPLER FOR SHALLOW FROZEN SOIL
Authors: GOIT J. B. , SHEPPARD M. I.
Published: March 2010

not available
MNII-FULVIC ACID COMPLEXING EQUILIBRIUM MEASUREMENTS BY ELECTRON SPIN RESONANCE SPECTROMETRY
Authors: GAMBLE D. S. , SCHNITZER M. , SKINNER D. S.
Published: March 2010

Electron spin resonance (ESR) spectrometry was used to determine weighted average equilibrium functions [Formula: see text] for water-soluble complexes formed between fulvic acid and divalent manganese. [Formula: see text] values ranged from 0.2 × 10−2 (at pH 6.15) to 0.5 × 10−3 (at pH 6.45) and were in excellent agreement with [Formula: see text] values determined previously for Mn–fulvic acid complexes by an ion-exchange method. The ESR method was found to be more sensitive, convenient and faster than the ion exchange procedure. From the data presented in this and in earlier publications it appears that MnII is bound simultaneously electrostatically and by hydrogen-bonding as Mn(OH2)62+ to fulvic acid donor groups in outer sphere complexing sites. These complexes are likely to be unsymmetrical.
AN ASSESSMENT OF THE SOIL ACIDITY PROBLEM IN ALBERTA AND NORTHEASTERN BRITISH COLUMBIA
Authors: PENNEY D. C. , NYBORG M. , HOYT P. B. , RICE W. A. , SIEMENS B. , LAVERTY D. H.
Published: March 2010

The amount of cultivated acid soil in Alberta and northeastern British Columbia was estimated from pH values of farm samples analyzed by the Alberta Soil Testing Laboratory, and the effect of soil acidity on crops was assessed from field experiments on 28 typical acid soils. The field experiments consisted of two cultivars of barley (Hordeum vulgare L.) and one cultivar each of rapeseed (Brassica campestris L.), red clover (Trifolium pratense L.) and alfalfa (Medicago sativa L.) grown with and without lime for 2 yr. There are about 30,000 ha of soils with a pH of 5.0 or less where soil acidity seriously restricts yields of all four crop species. There are approximately 300,000 ha with a soil pH of 5.1–5.5 where liming will on the average increase yields of alfalfa by 100%, yields of barley by 10–15%, and yields of rapeseed and red clover by 5–10%. There are a further 1,600,000 ha where soil pH ranges from 5.6 to 6.0 and liming will increase yields of alfalfa by approximately 50% and yields of barley, rapeseed and red clover by at least 4–5%.
FIBER CONTENT, PARTICLE-SIZE DISTRIBUTION AND SOME RELATED PROPERTIES OF FOUR PEAT MATERIALS IN EASTERN CANADA
Authors: LEVESQUE M. , DINEL H.
Published: March 2010

The effects of dispersion and sieving on the determination of fiber content was studied using four peat materials selected for their range of properties. In addition, a method of particle-size analysis of peat materials and chemical characterization data of the particular-size fraction are presented. Controlling the sieving operation effected a reduction in the coefficient of variation of the fiber content data to 2.7% as compared with 26.7% for the conventional rubbed fiber method. The somewhat more effective dispersion of the peat in 0.025 M pyrophosphate than in water did not compensate for the associated disadvantage of increased ash content of the pyrophosphate-treated samples. Thus, the recommended procedure involves dispersion of peat in water for 16 h. The proportion of the 100-mesh (0.15-mm) fraction reflected both the stage of decomposition and the botanical origin of the peat materials. Thus, particle-size fraction would be useful in the characterization of peat materials. Cation exchange capacity and content of both Fe and P varied inversely with particle size.
FIELD PERFORMANCE OF THE DEW-POINT HYGROMETER IN STUDIES OF SOIL–ROOT WATER RELATIONS
Authors: NNYAMAH JOE U. , BLACK T. A.
Published: March 2010

In situ measurements of soil water matric potential and root xylem water potential in a Douglas fir forest using a Wescor HR-33T dew-point microvoltmeter and PT51-10 hygrometers are described. Root xylem water potential measurement required tangential insertion of the hygrometer into the root xylem and sensor protection from plant resins using gypsum powder. Soil water matric potential measurements were compared with matric potentials computed using gravimetric and neutron meter measurements of soil water content and laboratory soil water retention data, while root water potential measurements were compared with measurements made using the pressure chamber method. The comparisons showed agreement to within ± 0.3 bar over an 8-bar range. There was good agreement between soil water matric potentials determined using the dew-point and psychrometric modes of operation of the instrument. The root xylem water potential showed a marked diurnal response to atmospheric demand.
PHOSPHATE SOLUBILITY IN DRIED FOREST FLOOR SAMPLES FROM NEW BRUNSWICK SOILS
Authors: MAFTOUN M. , KRAUSE H. H.
Published: March 2010

The forest floors of 20 soils supporting adult forest growth in New Brunswick were sampled and subjected to a study of P solubility in various reagents and P retention in the presence of variable amounts of Al. The organic surface accumulations contained from 430 to 1,280 ppm total P. After drying at 60 C, 6–28% of the total P was soluble in distilled water. Similar proportions of P were extracted with 0.002 N H2SO4, and slightly larger proportions by anion exchange resin. Extraction with 1 N HClO4 removed from 13 to 36% of the total P. Major portions of added [Formula: see text]were recovered by resin extraction from the organic substrates. Addition of Al reduced the recovery of added [Formula: see text] by various degrees, depending on the amount of Al added and origin of the organic sample.
THERMODYNAMIC CHARACTERIZATION OF WATER ADSORBED ON PEAT
Authors: KAY B. D. , GOIT J. B.
Published: March 2010

A preliminary thermodynamic characterization of water adsorbed on peat of sphagnum origin has been completed. The characterization has indicated that this organic material has a reactivity with respect to water which is similar to that of a montmorillonite clay. Under the relatively dry conditions of this study, less water was adsorbed by samples with a very low rubbed fibre content. The relative partial molar heat content of the adsorbed water approached the latent heat of fusion at water contents of about 16%. Additional measurements are required in the range of relative vapor pressures of 0.0–0.5 in order to determine if Halsey’s theory for adsorption on heterogeneous surfaces is applicable to the adsorption of water on peat.
HUMIC AND FULVIC ACIDS IN SEDIMENTS AND SOILS OF AGRICULTURAL WATERSHEDS
Authors: WHITBY L. M. , SCHNITZER M.
Published: March 2010

Humic and fulvic acids were extracted from suspended and bottom sediments and soils of small agricultural watersheds of Southern Ontario and characterized by chemical and spectrophotometric methods and by chemical degradation. Soil humic and fulvic acids were found to be similar to sediment humic and fulvic acids, respectively, in elemental and functional group composition and in surface structural features. Metal-binding capacities of sediment and soil humic and fulvic acids were estimated from their CO2H and phenolic OH group contents. Because watershed soils contained per unit weight considerably more humic materials than did adjacent bottom sediments, the metal-binding capacity due to humic and fulvic acids in the watershed soils was considerably higher than that due to humic and fulvic acids in the sediments. Major products resulting from the alkaline KMnO4 oxidation of soil and sediment humic and fulvic acids were benzenecarboxylic and phenolic acids. The chemical, spectrophotometric and degradation data indicated that sediment and soil humic substances had similar chemical structures.
A BURIED PALEOSOL IN THE HUDSON BAY LOWLAND, MANITOBA: AGE AND CHARACTERISTICS
Authors: MILLS G. F. , VELDHUIS H.
Published: March 2010

A Brunisolic–paleosol soil sequence is described from an ancient marine strandline in the Hudson Bay Lowland of northern Manitoba. The paleosol, underlying a present-day Brunisolic soil, is almost an exact morphologic counterpart of the contemporary soil. A radiocarbon date from the upper horizon of the buried soil indicates a minimum age of 2,380 ± 120 yr for the contemporary Brunisolic soil. The established geochronology of the Hudson Bay Lowland indicates that the marine beach on which this soil sequence is found was deposited about 7,000 YBP. The paleosol, therefore, may have developed over a maximum time interval of 4,500 yr allowing for a possible age difference between the two soils of up to 2,000 yr. However, a precise relationship between time and soil development can not be determined from this study. Because of limitations inherent in comparative soil morphology, uncertainty about the absolute age of the paleosol and difficulty in interpreting single radiocarbon dates, it is just as possible that both soils could develop over similar time intervals. This possibility is supported by the similar morphology of the two soils.
SURFACE APPLICATION OF GYPSUM AND AMMONIUM NITRATE FOR AMELIORATION OF A BLACK SOLONETZ SOIL
Authors: CARTER M. R. , WEBSTER G. R. , CAIRNS R. R.
Published: March 2010

Heavy rates of gypsum surface applied alone and in combination with ammonium nitrate to a Black Solonetz under dryland conditions favorably affected the chemical properties of the Ap and Bnt horizons and increased water penetration into the Bnt. Gypsum alone was equally as effective in ameliorating the soil as the combined treatment.
SITE CHARACTERISTICS, MORPHOLOGY AND PHYSICAL PROPERTIES OF SELECTED ORTSTEIN SOILS FROM THE MARITIME PROVINCES
Authors: WANG C. , MCKEAGUE J. A. , BEKE G. J.
Published: March 2010

Ortstein horizons at two sites in the Maritime Provinces were found to be strongly developed and continuous in poorly drained locations in the observation trenches, and intermittent at well drained locations. Roots did not penetrate the ortstein horizons but most ortstein clods were permeable to water, with saturated hydraulic conductivities ranging from about 0.1 to 31 cm/h. The unconfined compression strength of dry or moist ortstein clods usually exceeded 5 kg/cm2 and this is suggested as a limit to aid in separating weakly cemented materials from ortstein. The general environment of ortstein and its significance as related to land use are discussed.
EVAPORATION FROM TWO POROUS MEDIA DURING DIURNAL RADIATION CYCLES
Authors: NAGPAL N. K. , BOERSMA L.
Published: March 2010

The process of evaporation from porous media subjected to diurnal radiation cycles was studied. Information about pore size effects on evaporation was also obtained. Two porous media consisting of glass beads with diameters ranging from 53 to 74 μm and from 149 to 210 μm were used. Rates of water loss from the initially saturated media varied during the diurnal cycle. The initial rise in rate of surface irradiation increased the rate of water loss from both media. For the coarser material the rate of evaporation continued to increase for several hours after the maximum rate of irradiation was reached while for the finer material the rate of evaporation reached a maximum value even before the maximum rate of irradiation was attained. As a result, the ratio of the evaporation rates, Ecoarse/Efine, varied during the day from approximately 1.0 during periods of low evaporative demand to 2.60 during periods of high evaporative demand with an average value of 1.47 for the full day. The total amount of water lost per day from each medium remained constant during a 7-day experimental period, even though the surface layers dried out during periods of high irradiation. The pore size dependency of the rate of water loss was shown to be determined by the hydraulic conductivities of the porous media. The rates of water loss predicted by unsaturated water flow equations agreed well with the experimental data.
DRYLAND SOIL SALINITY: EFFECT ON THE YIELD AND YIELD COMPONENTS OF 6-ROW BARLEY, 2-ROW BARLEY, WHEAT, AND OATS
Authors: BOLE J. B. , WELLS S. A.
Published: March 2010

Six-row barley outyielded 2-row barley which outyielded wheat and oats in field plots on non-irrigated saline soils in southern Alberta. Salinity reduced the number of 6-row barley spikes less than it did the number on other cereals compared to spike production on adjacent non-saline soils. More kernels per spike were maintained on 6-row barley than on the other cereals under the salinity stress but average kernel weight was not differentially affected. Although salinity reduced the germination of wheat to a greater extent than it did the other cereals, adequate stands of all cereals were established and germination was not a major factor except on a plot where salinity stress was combined with spring drought. Six-row barley did not maintain its salt-stressed yield advantage over the other cereals under the drought conditions on a non-saline soil. The tolerance of cereals to osmotic stress thus differed from the tolerance to drought stress under dryland field conditions.
ALKALINE CUPRIC OXIDE OXIDATION OF ROOTS AND ALKALINE-EXTRACTABLE ORGANIC MATTER OF CHERNOZEMIC SOILS
Authors: DORMAAR J. F.
Published: March 2010

Alkaline cupric oxide oxidation was performed on roots of three grass species, on humic substances from three Chernozemic soils, and on three known compounds. The three grass species were Stipa comata Trin. & Rupr., Stipa spartea Trin. var. curtiseta Hitchc, and Festuca scabrella Torr., the three Chernozemic soils were Brown, Dark Brown and Black, and the three known compounds were vanillin, p-hydroxybenzaldehyde, and syringaldehyde. The intent of the study was to obtain a qualitative overview of the set of ethyl ether-soluble products. The gas chromatographic patterns were, therefore, qualitatively assessed and only some of the major peaks were tentatively identified. The ethyl ether-soluble fraction represented only up to 5.7% of the total root C. Most of the compounds identified in the root digests were also present in digests of the alkaline-soluble humic substances. There were quantitative differences for each chromatographic peak among root species, among time of sampling and growth location, and among extraction procedures of humic substances. The oxidation of the three known compounds in turn led to a number of compounds. The CuO-NaOH oxidation may thus cause alterations in similar compounds released from the original structure which will lead to either inflated or deflated yields of compounds that were part of the original structure.
CLAY MINERALS IN CANADIAN SOILS: THEIR ORIGIN, DISTRIBUTION AND ALTERATION
Authors: KODAMA H.
Published: March 2010

A literature survey was conducted to collect mineralogical data of Canadian soils. In the past 40 years, clay mineralogical data of varying precision have been reported for approximately 1200 samples from more than 380 pedons. Based on the data, (1) the distribution of clay minerals was examined physiographically, (2) an investigation was made to relate specific changes in clay minerals of pedons within a physiographic region to taxonomy, and (3) a comparison was made of the clay mineral alteration in the pedons of the same order in different physiographic regions. The results indicated that virtually no or minor alterations of clay minerals had occurred in pedons of many Canadian soils with the exception of Podzolic soils and to a limited extent, Brunisolic, Luvisolic and Gleysolic soils. In the Podzolic soils, chlorite disappeared or diminished in surface horizons, and micas and possibly some chlorites were transformed by hydration into partially or fully expansible clay minerals. For general soil clay mineral characterization, the analyses of one subsoil sample of a pedon would appear to be adequate for most soil orders. However, clay mineralogy has a potential to go much further in distinguishing minor changes and subtle differences in clay minerals. Such information would be useful in specific studies of soil development and in assessing trends in early stages of weathering. The current priorities of soil clay mineralogy in Canada should be improvement of methods of quantification and increasing the standardization of methodology and interpretation of results.
NUCLEIC ACID BASES IN SOILS AND THEIR ASSOCIATION WITH ORGANIC AND INORGANIC SOIL COMPONENTS
Authors: CORTEZ J. , SCHNITZER M.
Published: March 2010

Purines and pyrimidines were determined by ion-exclusion chromatography in 15 soil samples of widely differing pedological origins and in humic fractions isolated from these soils. The nucleic acid bases tended to concentrate in humins and fulvic acids (FA) rather than in humic acids. N in purines and pyrimidines constituted up to 7.4% of the soil-N and up to 18.6% of the N in a FA. The distribution of nucleic acid bases in soils and humic fractions was similar. Guanine, cytosine and adenine were detected in all samples, and thymine in most, while uracil and 5-methyl cytosine were found less frequently. The predominance of guanine and cytosine suggested a microbial DNA origin for the nucleic acid bases. Evidence was obtained that the nucleic acid bases interacted not only with humic materials but also with inorganic soil components such as clays and hydrous oxides. Our data show that purines and pyrimidines accounted for up to 16% of the unidentified N in a soil and for up to 40% of the N in a FA so far not yet identified. This suggests that more attention be given to nucleic acid bases when considering the N status of soils.
SURFACE AREA AND EXCHANGE CAPACITY OF CLAY IN RELATION TO THE MINERALOGICAL COMPOSITION OF GLEYSOLIC SOILS
Authors: KIMPE C. R. DE , LAVERDIERE M. R. , MARTEL Y. A.
Published: March 2010

A study was made to determine to what extent the mineralogical composition of the clay fraction can be related to the total surface area (So) as well as the cation exchange capacity (CEC) values of Gleysolic soils. Eleven soil profiles were sampled in the regions of Montreal, Quebec and Lake St-Jean. Mineralogical composition, surface area and exchange capacity of the clay fraction, and surface area and exchange capacity of the soils were determined. Results showed good agreement between the experimental measurements of surface area and exchange capacity and the calculated figures obtained by using mineralogical composition and theoretical values of So and CEC of each mineral. The variations in the mineralogical composition of the clay fraction were related to the difference in the degree of evolution of the soils in the three regions.
A COMPARISON OF VARIOUS MEANS OF MEASURING THE DEGREE OF DECOMPOSITION OF VIRGIN PEAT MATERIALS IN THE CONTEXT OF THEIR RELATIVE BIODEGRADABILITY
Authors: LÉVESQUE M. P. , MATHUR S. P.
Published: March 2010

Eleven physical and chemical properties of 26 peat materials from a total of five virgin profiles were determined and statistically analyzed for correlations among attributes that relate to the degree of decomposition, and with the rates at which the materials biodegraded. Estimation of fiber content made routinely by pedologists in the field correlated with relative, biodegradability better than any other criterion of decomposition and humification.
THE EFFECT OF Ca ON TRIALLATE ACTIVITY
Authors: McKERCHER R. B. , McGREGOR W. R.
Published: March 2010

Applications of Ca to soil in both growth chamber and field experiments increased triallate [S-(2,3,3-trichloroallyl)-diisopropylthiocarbamate] activity. Ca appears to affect the distribution of triallate between the colloid and soil solution causing a shift of triallate toward the solution phase. These effects are measurable in pot experiments at Ca additions of about 1 meq/100 g soil or at field applications of 2.5 tonnes per hectare (1 ton per acre) of Ca(OH)2.
THE MICROBIOLOGICAL FORMATION OF BASIC FERRIC SULFATES. 3. INFLUENCE OF CLAY MINERALS ON CRYSTALLIZATION
Authors: IVARSON K. C. , ROSS G. I. , MILES N. M.
Published: March 2010

Solutions of ferrous sulfate (pH 3.0) containing Mg- Al-, NH4- and alkali-saturated montmorillonite were inoculated with the iron-oxidizing bacterium Thiobacillus ferrooxidans and incubated for 451 days. In presence of K, NH4, Na and Li-montmorillonite the respective basic ferric sulfates formed were jarosite, ammoniojarosite, natrojarosite and hydronium jarosite. Their rates of formation were in the sequence listed and were slower than in systems containing no clay minerals. Hydronium jarosite also formed in the Mg- and Al-montmorillonite systems but at a slower rate than in the Li system. Fifteen to 20% of the montmorillonite was dissolved. In presence of muscovite, jarosite formed and the release of K resulted in some hydration of mica interlayers.
YIELD AND CHEMICAL COMPOSITION OF RAPE IN RESPONSE TO NITROGEN, PHOSPHORUS AND POTASSIUM
Authors: SHEPPARD S. C. , BATES T. E.
Published: March 2010

A field trial was conducted for 3 yr to monitor the response of seed rape (Brassica napus L.) to several fertilizer treatments at two seeding dates. The fertilizer treatments consisted of 0–200 kg N/ha, 0–100 kg P/ha and 0–180 kg K/ha broadcast with or without 4.2–7–0 kg N-P-K/ha banded below the seed. Total yield, seed yield, plant height, lodging index, seed contents of oil and N, and leaf contents of N, P, K, Ca, Mg, Mn, Cu, Zn and B were measured. Rape responded to broadcast N with maximum seed yields at 100 kg N/ha independent of seeding date or banded fertilizer. Leaf concentrations of N, P and K were influenced by nitrogen supply but the critical leaf N concentration varied considerably. Response to 7 kg P/ha banded or 25 kg P/ha broadcast occurred when the soil P was less than 10 μg/cc. The critical leaf P concentration was less than 0.2%. Very little response to broadcast K was observed with a soil test of approximately 60 μg K/cc. The early seeding date (late April to early May) increased seed yields an average of 225 kg/ha over the late seeding date (late May) and the band placement of fertilizer increased seed yields an average of 55 kg/ha over comparable treatments without banded fertilizer. Seed yield and leaf elemental composition are presented as functions of broadcast nitrogen, phosphorus and potassium.
MICROBIAL ACTIVITY IN A PINUS BANKSIANA LAMB. FOREST FLOOR AMENDED WITH NITROGEN AND CARBON
Authors: FOSTER N. W. , BEAUCHAMP E. G. , CORKE C. T.
Published: March 2010

Organic matter with high C:N ratios accumulated on mineral soil retards cycling of nutrients in semi-mature jack pine (Pinus banksiana Lamb.) ecosystems. To test whether N as ammonium sulfate or as urea stimulates organic matter decomposition, 200 kg N∙ha−1 were applied to mixed L and F horizon material in Warburg respirometer flasks. Soils were incubated at 13 °C and constant 0.3 bar (340%) moisture; O2 consumption was measured as an index of microbial activity. In urea-treated soil, O2 uptake was much higher than with unamended soil over a 7-wk incubation period, and this indicated a marked effect of urea on microbial activity. The fact that ammonium sulfate depressed respiration rates was evidence that stimulation of microbial respiration by urea was not initially related to added N, but rather to an increase in soil-soluble C resulting from soil pH changes during hydrolysis. In the presence of a C source (ethanol), a 5-fold increase in respiration was noted, whereas C and urea together produced a 15-fold increase in activity. These results suggest that readily available energy for microbial growth, rather than N, limits the initial decomposition of L and F materials in this pine stand. Once microbial demand for C is satisfied, a further increase in microbial activity is produced by N addition.
DISPERSION AND DISSOLUTION EFFECTS DURING ULTRASONIC DISPERSION OF GLEYSOLIC SOILS IN WATER AND IN ELECTROLYTES
Authors: HINDS A.A. , LOWE L. E.
Published: March 2010

The dispersive efficiency of ultrasonic vibration of Gleysolic samples in water or in electrolytes was comparable to that obtained by the peroxide-calgon method, with insonation in electrolytes yielding generally higher recoveries of clay than insonation in water. Ultrasonic dispersion in water was accompanied by considerable dissolution of Fe, Al, Si and organic-C. B horizon samples released on average about five times as much Fe, Al and Si as A horizons. The converse was found for organic-C release. Dissolution resulting from ultrasonic treatment averaged 49.6, 48.4 and 228 ppm (soil basis) Fe, Al and Si, respectively, for A horizons, and 286, 275 and 1492 ppm, respectively, for B horizons. The ratios of released Fe, Al and Si were consistently in the neighborhood of 1:1:5. Fe and Al dissolution were inversely related to organic-C release. Ultrasonic disperson in 0.01 M CaCl2 0.01 M BaCl2 or 0.1 M NaCl resulted in substantial suppression of these dissolution effects, with CaCl2 being the most effective. For Gleysolic soils, ultrasonic vibration is likely to give higher yield of less-altered organo-clay complexes than ultrasonic dispersion in water.
FLUORESCENCE EXCITATION SPECTRA OF HUMIC SUBSTANCES
Authors: GHOSH KUNAL , SCHNITZER M.
Published: March 2010

Fluorescence excitation spectra of fulvic acid (FA) and humic acid (HA) were recorded at different pH as well as at different netural salt concentrations. Spectra of both FA and HA exhibited distinct bands at 465 nm, while spectra of FA showed additional bands at 360 nm. Fluorescence intensities decreased with decreasing pH and increasing ionic strength. This is due to decreasing ionization, increasing particle association, and to coiling of macromolecular structures. The fluorescence characteristics of FA and HA were observed to be related to the free radical content, color, and phenolic structures. Our data show that fluorescence excitation spectra can be utilized for differentiating between soil FA and HA.
THERMODYNAMIC PROPERTIES OF SYNTHETIC BASIC ALUMINITE [Al4(OH)10SO4∙5H2O] FROM SOLUBILITY DATA
Authors: SINGH S. SHAH
Published: March 2010

From the solubility equilibrium data of basic aluminite at three temperatures, the standard free energy change (ΔG°), enthalpy change (ΔH°), and entropy change (ΔS°) were determined as 160.02 kcal∙mole−1, 65.48 kcal∙mole−1 and 317.1 cal∙deg−1]mole−1, respectively. From these values the free energy of formation (ΔGf°) and the heat of formation (ΔHf°) of basic aluminite was also computed and was 1465.25 kcal∙mole−1 and 1682.08 kcal∙mole−1, respectively.
METHODE NOUVELLE DE PREPARATION DE COUPES MINCES DES TOURBES ET DES GYTTJA
Authors: PARENT LÉON ETIENNE , PAUZÉ FERNAND J. , BOURBEAU GÉRARD A.
Published: March 2010

The proposed method for the preparation of peat and gyttja samples for thin sectioning reduces or eliminates perturbation risks caused by the usual peat or gyttja dehydration processes, dissolution of organic substances, percolation of the substitution liquids through samples, negative pressure, osmotic pressure, as well as delicate manipulations to extract crystalline embedding materials. The method includes sample fixation with a noncoagulant fixative, acrolein, mild dehydration with tetrahydrofuran (THF), and gradual impregnation with a non-crystalline embedding medium, celloidin. Thin sectioning with the sliding microtome produces 15–20 μm sections.