bluuebunny/crossref_metadata_2025 huggingface dataset:
NITROGEN FERTILIZER REQUIREMENTS FOR BARLEY WHEN APPLIED WITH CATTLE MANURE CONTAINING WOOD SHAVINGS AS A SOIL AMENDMENT
Authors: MACKAY D. C. , CAREFOOT J. M. , SOMMERFELDT T. G.
Published: March 2010

In an 8-yr experiment on an irrigated Dark Brown Chernozemic soil, four rates of N (0, 34, 67 and 101 kg ha−1), applied annually with 45 t ha−1 of manure containing softwood shavings (avg. of 46% dry wt) produced a linear yield response (from 3.5 with the check to 4.3 t ha−1 at the highest rate) of barley grain (Hordeum vulgare L. 'Galt'). There were large differences in yields among years, which could be attributed to weather factors, but there was no significant N × year response. Protein content increased linearly (from 11.2 to 13.5%), and both kernel weights and "test weights" (kg hL−1) decreased slightly but significantly with N applications. There was a pronounced "residual" effect of N rates on both grain yield (from 3.8 to 6.3 t ha−1) and protein content (from 10 to 13%) in the first year after applications of manure and N fertilizer ceased. These effects decreased rapidly and had practically disappeared by the end of the 3rd yr, although yields of all treatments remained high (about 5 t ha−1). Organic matter and N contents of the soil were increased by 70 and 41%, respectively, from the cumulative applications of shavings manure. It is concluded that application of manure containing large quantities of softwood shavings has a negligible effect on the N fertilizer requirements of the crop being grown. Beneficial residual effects of N fertilizer applied with the manure may result because of buildup of NO3-N throughout the soil profile, and likely also because of N release from readily mineralized organic compounds or microbial biomass. However, this effect was not reflected in soil tests for readily mineralizable N by NO3 incubation or KCl digestion methods and the effects were practically dissipated after 3 yr. The recovery of applied N fertilizer by the crops was high at all rates (61–79%), and essentially all of the N applied (fertilizer + manure) was accounted for by crop removal + increased soil N. Key words: Mineralizable-N soil tests, Chernozemic soil, repeated fertilizer applications, residual effects
FERTILITY GROUPING OF MONTREAL LOWLANDS SOIL MAPPING UNITS BASED ON SELECTED SOIL CHARACTERISTICS OF THE PLOW LAYER
Authors: NOLIN M. C. , WANG C. , CAILLIER M. J.
Published: March 2010

Ten soil properties, including texture, pH, available phosphorous, cation exchange capacity, exchangeable cations and organic carbon, were determined from the Ap horizons of 91 map units of two Montreal Lowlands counties. Multivariate analysis techniques were used to classify the soils into fertility groups. Nine fertility groups were derived from cluster analysis. Principal component analysis yielded two components which accounted for more that 75% of the variance. These principal components were related to soil texture and fertilizer management factors. They confirmed the grouping obtained by cluster analysis. Multiple discriminant analysis distinguished these fertility groups and allocated new soil mapping units to one of them using discriminant functions. Clay content, pH, exchangeable Ca and available P were selected as the more potent and significant variables in descriminating groups. This work demonstrated that multivariate analysis has considerable promise in deriving meaningful interpretive grouping from selected soil parameters. Key words: Fertility, interpretive grouping, soil quality, multivariate analysis
RECOVERY OF 15N-LABELLED UREA AS INFLUENCED BY STRAW ADDITION AND METHOD OF PLACEMENT
Authors: MALHI S. S. , NYBORG M. , SOLBERG E. D.
Published: March 2010

Field experiments were conducted during 1982–1983 at two locations (Rimbey and Ellerslie) in north-central Alberta to determine the influence of date of application (mid-October, late October and spring), method of placement (incorporation, banding and nesting) and straw (0 and 3.4 t ha−1) on the recovery of 15N-labelled urea in plants and soil at harvest. The rate of N was 50 kg N ha−1. The recovery of 15N in mature barley plants at both locations was greater with spring application as compared to fall application, and greater with banding or nesting compared to incorporation. At Rimbey, the average recovery, in plants plus soil, of incorporated urea N was lower with October applications (43% for mid and 55% for late) as compared to spring application (89%). Banding or nesting increased the N recovery of October applications. With spring application, there was more immobilization of applied N when incorporated into soil as compared to band or nest placement. Also there was more immobilization of applied N when straw was added to the soil, but banding or nesting tended to overcome the immobilization effect of straw so that the plant N recovery was greater with banding or nesting as compared to incorporation. At the Ellerslie location, there was heavy rain with consequent saturated topsoil in late June and early July. Recovery of fall-applied N in plants was low, and even with nesting the recovery was only 13%. There was substantial immobilization of applied N at Ellerslie. With spring application, nesting overcame the large immobilization effect and produced normal recovery of applied N in the plants. Addition of straw resulted in more immobilization of applied urea N, particularly when urea was incorporated. The 15N recovery in plants plus soil of spring-applied N indicated N losses during the growing season and the losses were much greater at Ellerslie than at Rimbey. Key words: Band placement, fall application, immobilization of N, incorporation, 15N, N losses, nest placement, spring application
TRANSFORMATIONS AND DISPOSITION OF LATE-FALL APPLIED NITROGEN DURING WINTER IN SOUTHERN SASKATCHEWAN
Authors: SELLES F. , LEYSHON A. J. , CAMPBELL C. A.
Published: March 2010

Prairie farmers are interested in applying nitrogen (N) in the fall or winter to reduce fertilizer costs and allow a better distribution of labor and machinery use. Two studies were conducted in southwestern Saskatchewan to determine the consequences of applying N in late fall. In the laboratory, fertilizer N barely penetrated into the snow at constant subzero temperatures, but under freeze-thaw conditions, urea and ammonium nitrate descended 27 cm in 3 d. In the field, ammonium nitrate and urea were applied to snow-covered and bare microplots of grass sod and cereal stubble (1981–1982) and grass sod only (1985–1986). Nitrogen from ammonium nitrate penetrated deeper into the snow than N from urea. Nitrogen recovery in April 1982 was 55–59% from ammonium nitrate and 39–51% from urea, but was near 100% for both sources on bare soil treatments in April 1986. More N was recovered when fertilizer was applied to bare than to snow-covered soil, especially during 1985–1986 when all the applied fertilizer was blown off the snow-covered plots. Mineral N generally declined from fall to spring in all treatments, probably because of denitrification and immobilization. In 1985–1986, a period of extremely low temperatures in late fall resulted in no movement or transformation of N until after early December. By late January, periods of above-zero soil temperatures resulted in substantial mineralization of soil organic N, in the fertilized plots. This apparent priming effect was attributed to perturbations in the organic matter and microbial biomass due to fertilizer application and freezing and thawing. Following this period there was a general decrease in mineral N towards spring, as observed in 1981–1982. Producers must consider the benefits of using labor and equipment more efficiently and of lower fertilizer cost in the fall against the risk of large potential N losses over winter. Key words: Urea, ammonium nitrate, N recovery, frozen soils, fertilizing in winter
PREDICTION OF THE PERSISTENCE OF THE TRIAZINE HERBICIDES ATRAZINE, CYANAZINE, AND METRIBUZIN IN REGINA HEAVY CLAY
Authors: SMITH A. E. , WALKER A.
Published: March 2010

The persistence of the herbicides cyanazine, metribuzin, and atrazine was studied at different controlled temperature and moisture contents in Regina Heavy Clay soil. Degradation of the herbicides approximated first-order kinetics at temperatures in the range 5–30 °C and at moistures of above 20%. The breakdown of cyanazine was faster than metribuzin, which, in turn, was more rapid than atrazine. The breakdown of the three herbicides under field conditions, following June applications of 1.0 kg ha−1, was measured. Over 90% of the applied cyanazine had dissipated within 56 d, while the metribuzin and atrazine were more persistent, with approximately 30% of the initial treatment remaining at the end of the growing season. In all cases, there was no leaching of the chemicals below 10 cm. The laboratory data were used in conjunction with meteorological records in a computer program to simulate the dissipation pattern for the herbicides. There was good agreement between the observed and predicted residue levels for cyanazine, and a reasonable agreement for atrazine. For metribuzin, the model underestimated the rate of loss. Key words: Herbicides, atrazine, cyanazine, metribuzin, predicted field persistence
POTASSIUM EXCHANGE AND FIXATION IN SOME SOUTHERN ONTARIO SOILS
Authors: Ross G. J. , GAMBLE DONALD S. , CLINE R. A.
Published: March 2010

Long-term (8 yr) K+ fertilization experiments were started in 1983 on Jeddo clay loam, Smithville silt loam, Oneida loam, and Vineland sandy loam in the Niagara region of southern Ontario to study K+ exchange and fixation in relation to K+ uptake by grapes. Potassium fertilization at rates of 0, 100, 200, 400, and 600 kg K+ ha−1 was discontinued after 4 yr to record the build-up of soil K+ with fertilization and its decline after fertilization ceased. This paper reports the results on K+ exchange and fixation during the 4-yr K+ fertilization period. The clay mineralogy of the soils was similar with their clays containing mainly mica and smaller amounts of vermiculite, chlorite, quartz, and feldspars. There was a highly significant linear relationship between rates of applied K+ and K+ fractions of exchangeable cations for every soil in every year of K+ application. Exchangeable K+ concentrations in the coarse-textured Vineland soil increased sharply from the first to the second year of K+ application. However, there was no consistent increase of exchangeable K+ concentrations with time in the finer-textured soils for the first 2-4 years of K+ application. This was attributed mainly to K+ fixation. This interpretation was supported by chemical and X-ray evidence that showed reduced K+ fixation capacity and transformation of vermiculite to a mica-like mineral at the high rate of K+ application. Potassium exchange equilibria and standard Gibbs free energies for the exchange of (Ca2+ + Mg2+) by K+ were calculated using the theory of multiple ion exchange equilibria. Standard Gibbs free energy values for this exchange became more negative with increase in clay and vermiculite contents of the soils which was attributed to the strong adsorption of K+ in vermiculite and vermiculite-like minerals that were concentrated in the clay fraction. Clay content is therefore the dominant factor determining K+ exchangeability in the soils of the Niagara region of southern Ontario. Key words: soil mineralogy, vermiculite contents, potassium exchange equilibria, standard Gibbs free energy
CORRECTING SOIL VOLUMETRIC WATER CONTENTS FROM A DIRECT-READING TIME DOMAIN REFLECTOMETRY INSTRUMENT (IRAMS)
Authors: TOPP G. C. , CULLEY J. L. B.
Published: March 2010

Determination of volumetric soil water content (θ) using time domain reflectometry (TDR) is well established. A commercially available instrument (IRAMS) (the IRAMS (Instrument for Reflectometry Analysis of Moisture in Soils) is a trademark registered by Foundation Instruments Inc. of Ottawa) is now available which incorporates computer software, thus providing direct readouts of θ. A field study of the operation of the IRAMS showed that it operates consistently and repeatedly. The IRAMS values were higher but related linearly to those obtained using a TDR cable tester and manual calculations of travel times. A linear correction of the IRAMS readings is proposed and possible causes are suggested for the observed deviations from expected values. Key words: Time domain, reflectometry, soil water content, field
EFFETS DE DIFFERENTES PRATIQUES SYLVICOLES ET DE L'INTRODUCTION DE VERS DE TERRE SUR LA STRUCTURE DU SOL EN PLANTATIONS DE FEUILLUS
Authors: BRAIS S. , BHÉREUR P. , GAGNON D. , CODERRE D.
Published: March 2010

Impacts of silvicultural practices on soil structure were evaluated in hardwood plantations. On two different sites, four treatments (mechanical weed control, herbicide weed control, seeding of nitrogen-fixing companion species and a control) were undertaken, with and without earthworm introduction, according to a complete randomized block design. Treatments had significant effects on the water stability of soil aggregates, macroporosity and bulk density. Earthworm introduction significantly increased macroporosity in control plots while decreasing it in the three other treatments. Key words: Soil structure, silvicultural practices, earthworm, Lumbricus terrestris
EFFECT OF CANOPY AND INCORPORATION ON METRIBUZIN PERSISTENCE IN SOILS
Authors: JENSEN K. I. N. , KIMBALL E. R. , IVANY J. A.
Published: March 2010

The half-life of metribuzin applied to a bare soil surface was calculated to be 3–7 d over four field tests. An artificial cover erected after application or a shallow incorporation increased the half-life of metribuzin approximately 2.5- to 3-fold. Leaching out of the 0- to 5-cm-deep sampling zone could not account for loss of metribuzin. It was concluded that metribuzin persistence may be affected by volatility and/or photodecomposition losses under field conditions, especially shortly after application. Key words: Metribuzin half-life, volatility, photodecomposition, row width
THE CHEMICAL AND MINERALOGICAL COMPOSITION OF SOIL PARENT MATERIALS IN NORTHEAST ALBERTA
Authors: SPIERS G. A. , DUDAS M. J. , TURCHENEK L. W.
Published: March 2010

Seven major parent materials from the Athabasca oil sands area were investigated for detailed mineralogy and chemistry. The clay mineral species identified and quantified were mica, smectite, kaolinite, chlorite and vermiculite. The fine (50–250 μm) sand mineralogical suite was dominated by quartz, with lesser amounts of Na-, K-, and Ca-feldspars, and minor amounts of individual heavy mineral species. Electronoptical examination indicated that the feldspar grains in the parent materials have undergone extensive preglacial weathering. Regional mean levels of all analyzed elements (Al, Ca, Fe, K, Mg, Na, Mn, P, Cr, Co, Cu, Ni, Pb, Sr, V, and Zn), with the exception of Ca, are related to textural variability. The variability of Ca levels within the study area is related to the occurrence of calcareous parent materials. The highest levels of all major, minor, and trace elements were associated with either the Legend unit derived largely from Cretaceous bedrock or with the modern sediments of the Athabasca delta. Key words: Soil parent materials, clay mineralogy, trace element levels, sand mineralogy, feldspar morphology
IRRIGATION SUBSURFACE RETURN FLOWS AND WATER USE IN LYSIMETERS CONTAINING APPLE TREES
Authors: STEVENSON D. S.
Published: March 2010

For 9 yr, subsurface return flow measurements from irrigated lysimeters containing "Macspur McIntosh" apple trees (Malus domestica Borkh.) on MM 111 rootstocks were collected. Water use with and without a grass cover crop was calculated as irrigation plus summer precipitation minus drainage. Drainages were consistently and significantly lower, and therefore water use higher, under grass than under bare soil but the differences were not large. The times of irrigation and drainage events were not closely linked. Drainage followed irrigation anywhere from a day to many days, stretching at times into weeks or months. By far the largest drainages, however, occurred during the irrigation season. Irrigation amounts provided most of the water for return flows with summer or winter precipitation contributing little to the drainage. At the higher irrigation levels the return flow quantities and calculated water use quantities clearly indicate that sprinkler design flow quantities are too high for the area and that improvements in irrigation efficiencies are possible. Key words: Drainage, irrigation, lysimeters, water use, apple trees
THE WIND ERODIBILITY OF SOME ALBERTA SOILS AFTER SEEDING: AGGREGATION IN RELATION TO FIELD PARAMETERS
Authors: BLACK J. M. W. , CHANASYK D. S.
Published: March 2010

Average percentages of soil material > 0.84 mm diameter estimated from wind erodibility groups (WEG) are commonly employed in the appraisal of the wind erodibility of soils. Soil samples taken after seeding from four areas of Alberta were sieved on a Modified Rapid Rotary Sieve. Agreement between the sieving data and estimates of material > 0.84 mm made using the WEG was poor (r = 0.33). Samples from soil textural groups generally had twice as much material > 0.84 mm than predicted by the WEG. Using 350 soil samples the relationship between soil aggregates > 0.84 mm and (1) field estimated soil properties, and (2) soil management was investigated by multiple regression analysis. Aggregation was strongly dependent on soil texture (r = 0.67) with coarser-textured soils having fewer aggregates > 0.84 mm and thereby being more erodible. Increasing quantities of soil carbonates (up to 10%) increased soil erodibility. Preseeding tillage decreased erodibility. Conversely, postseeding packing operations increased erodibility except when a rodweeder was used. Type of seeding implement, rotations, and type of crop seeded (oilseeds versus grains) had no statistically significant effect on aggregation. The coefficient of multiple determination (R2) for the final model was 0.61. Results were corroborated by previous experimental findings and confirmed that the WEG are not accurate for Canadian Prairie soils. The study demonstrated that although soil texture and carbonate content played an important role, tillage had a considerable effect on soil erodibility. Key words: Wind erosion, soil erodibility, WEG, aggregation, soil management
MOVEMENT TO THE SUB-SOIL OF P APPLIED TO AN ACIDIC SOIL CROPPED TO TIMOTHY-GRASS FOR TWENTY-SIX YEARS
Authors: RICHARDS JOHN E. , BÉLANGER GILLES
Published: March 2010

Fertilizer P was applied annually (0, 15, 29 and 44 kg P ha−1 yr−1) for 26 yr to an acidic loam cropped to timothy (Phleum pratense L.). Some fertilizer P was translocated into the 30- to 45-cm depth of soil when 15 kg P ha−1 yr−1 was applied and into the 45- to 60-cm depth when 44 kg P ha−1 yr−1 was applied. The amount of P translocated increased with increasing rates of applied P. Key words: Fertilizer, phosphorus, leaching, translocation, movement
NATURE OF SMECTITES IN SOILS DEVELOPED ON BASALTIC SAPROLITE AND BASALTIC AND GRANITIC TILL IN NOVA SCOTIA
Authors: RUTHERFORD G. K. , LI LORETTA , ROSS G. J.
Published: March 2010

In Kings County Nova Scotia, soils have developed over pre-Wisconsinan basaltic saprolite and basaltic and granitic till. The clay fraction of the soil developed on the saprolite is predominantly a trioctahedral smectite and apparently has not been significantly changed by post-Wisconsinan weathering. The clay fraction of the Aej horizon of the soil developed on granitic till is dominantly composed of dioctahedral layer silicates, mainly mica with some montmorillonite and vermiculite, and that developed on basaltic till by smectite and vermiculite. Key words: Basaltic saprolite, trioctahedral smectite, post-Wisconsinan weathering
MICROBIAL BIOMASS AND EXTRACTABLE SULFATE SULFUR LEVELS IN NATIVE AND CULTIVATED SOILS AS INFLUENCED BY AIR-DRYING AND REWETTING
Authors: GUPTA V. V. S. R. , GERMIDA J. J.
Published: March 2010

Air-drying decreased (> 80%) microbial activity, microbial biomass carbon (MB-C) and sulfur (MB-S) levels of both native and cultivated soils. This resulted in a flush (~ 4 μg g−1) in the 0.01 M CaCl2 extractable SO4-S. Rewetting soils restored microbial activity and biomass contents to their original levels, but this led to immobilization of the SO4-S. Restoration of the MB-S levels was slower than MB-C levels. Thus, during drying and rewetting cycles, the MB-S pool acts as both a source and sink for the SO4-S pool in soil. Key words: Microbial activity, microbial biomass sulfur, extractable sulfate sulfur
BULK DENSITY OF SURFACE SOILS AND PEAT IN THE NORTH CENTRAL UNITED STATES
Authors: GRIGAL D. F. , BROVOLD S. L. , NORD W. S. , OHMANN L. F.
Published: March 2010

Relationships between bulk density (BD) and loss on ignition (LOI) for forest floor, shallow mineral soil (0–25 cm depth), and peat were described by exponential functions. The data were collected in forests across the North Central US. For forest floor, predicted BD, BDp = 0.073 + 2.369 exp(− 0.073 LOI), R2 = 0.75, (BDp in Mg m−3 and LOI in percent dry wt), and for surface mineral soil, BDp = 0.669 + 0.941 exp(− 0.240 LOI), R2 = 0.95. For peat, BDp = 0.043X + 4.258 exp(− 0.047 LOI), R2 = 0.89, where X is a dummy variable with a value of 0 for surface peat (0–25 cm depth) and 1 for subsurface peat (25–175 cm). Key words: Bulk density, loss-on-ignition
REDUCTION OF SECONDARY TILLAGE IN MOULDBOARD-PLOUGHED SYSTEMS FOR SILAGE CORN AND SPRING CEREALS IN MEDIUM-TEXTURED SOILS
Authors: CARTER M. R. , WHITE R. P. , ANDREW R. G.
Published: March 2010

Minimum tillage for soils that require regular cultivation consists of reducing the degree of secondary tillage and number of passes over the field. This study was conducted to determine whether one-pass mouldboard-ploughed systems were suitable for production of silage corn (Zea mays L.) and spring cereals (Hordeum vulgare L., Triticum aestivum L.) on loam to sandy loam soils (Humo-Ferric Podzol and Gray Luvisol) in the perhumid soil climate of Prince Edward Island. The effects of reduction in secondary tillage were gauged by characterizing crop yield and nutrient content, soil properties and structure, and relative economics. Plant growth, crop yield, and nutrient content were similar in all the mouldboard-ploughed systems. Soil chemical properties were not affected by reduction in secondary tillage, but the one-pass plough system did result in a macro-aggregate distribution with a greater proportion of large soil aggregates (9.5–16 mm) and a slight reduction in soil strength over the 10- to 25-cm soil depth. Macroporosity and soil density in the top 8 cm of soil were similar between tillage systems. Reducing both the degree of secondary tillage and number of tillage operations decreased both estimated cultivation costs and time of tillage per hectare by 26 and 39%, respectively. One-pass mouldboard-ploughed systems appear suitable for annual crop production on medium-textured soils under the soil environment of Prince Edward Island. Key words: One-pass tillage, soil properties, crop growth
EFFECT OF DATE OF APPLICATION ON THE FATE OF 15N-LABELLED UREA AND POTASSIUM NITRATE
Authors: NYBORG M. , MALHI S.S. , SOLBERG E.D.
Published: March 2010

Previous work in north-central Alberta showed large losses of fall-applied 15N-labelled N fertilizers over the winter, but determination was not made for the summer season. The objective of the present study was to discover the amount of 15N loss during both the non-cropped winter season and during the following cropped season. Field experiments were conducted at two sites with 15N-labelled urea and potassium nitrate (KNO3) applied in early October, late October, late winter and in the spring. The 15N-labelled fertilizers at 50 kg N ha−1 were incorporated into the soil. Plots were sown to barley in spring and harvested when mature. Recovery of 15N in soil samples taken before sowing in spring indicated over-winter N losses from October-applied N at both locations and especially with KNO3. At the Breton site spring recovery of 15N in soil from the October application was 69% with urea and only 30% with KNO3. The mechanism of N loss was primarily denitrification. The amount of 15N immobilized in the soil was greater with urea than KNO3 for both sites. The total recovery of October- or late winter-applied 15N fertilizer at harvest (plants plus soil) was low, with a range of 7–71%. The recovery from spring application was near-complete at the Innisfail site (≥ 84%) but at Breton, which had heavy rain and saturated soil in late June, recovery was low with urea (56%) and especially low with KNO3 (10%). It was estimated that 8 of 45 site-years had sufficient precipitation during June to cause prolonged soil saturation and consequent N loss. In all, major losses of 15N occurred in the non-cropped over-winter period at both sites, and occurred in the cropped season at one site. Key words: Denitrification, fall application of N, leaching, 15N, 15N balance, N fertilizer, N losses, winter application of N
RESIDUAL EFFECTS OF ALFALFA AND BROMEGRASS CROPPING ON YIELDS OF WHEAT GROWN FOR 15 SUBSEQUENT YEARS
Authors: HOYT P. B.
Published: March 2010

Twelve crops of wheat (Triticum aestivum L.) were grown over a 15-yr period after forage hay swards or a fallow-wheat rotation (control) on a fine-textured soil in northern Alberta. Nitrogen fertilizer was not applied to the forage crops nor to the wheat. Yields of wheat following alfalfa (Medicago sativa L.) ranged from 66 to 114% greater than those following control for the first eight crops. Yield differences started to decline thereafter, although the wheat yield after alfalfa was significantly higher than that after the control for the 10th crop in the 13th year after the sward breaking. The alfalfa contributed to the wheat yields through both the subsoil and topsoil as determined by interchanging topsoil between the former alfalfa and control plots. Yields of wheat after an alfalfa and bromegrass (Bromus inermis Leyss.) mixture were only slightly less than those after alfalfa alone, however, those after bromegrass alone were much less than those following alfalfa. Key words: Alfalfa, bromegrass, yields of subsequent wheat
COMPARISON OF DIRECT AND INDIRECT METHODS OF MEASURING FERTILIZER N UPTAKE IN WINTER WHEAT
Authors: ROBERTS T. L. , JANZEN H. H.
Published: March 2010

Two methods of estimating fertilizer N uptake (FNU) were compared using 11 site-years of data from four winter wheat experiments comparing different N sources, application methods and application times. Direct (15N) and indirect (difference) estimates of FNU were significantly correlated in 10 of the 11 site-year combinations. When plant uptake of applied N increased, both methods provided similar estimates of FNU and allowed treatment effects to be separated with comparable resolution. Neither method nor time of application had any apparent effect on the ability of the two methods to estimate FNU. Key words: Difference method, isotope dilution method, 15N, fertilizer efficiency, fertilizer recovery
LONG-TERM SOIL MOISTURE STATUS IN SOUTHERN ALBERTA
Authors: CHANG C. , SOMMERFELDT T. G. , ENTZ T. , STALKER D. R.
Published: March 2010

Nineteen years of soil moisture content data at Lethbridge and two locations near Turin (Turin 1 and Turin 2) in southern Alberta were examined to evaluate the efficiency of follow for conserving moisture, and to calculate the long-term mean amount of water recharge during growing and nongrowing seasons under a fallow-cereal, 2-yr rotation and a continuous cropping system. Soil samples were taken annually from 1969 to 1987 to a depth of 120 cm in 30-cm intervals in the spring (early May) and fall (late September). A method for testing differences of means between nonstandard data using localized uncertainty associated with sliding polynomial smoothing was used to test for differences in the soil moisture contents due to cultural practices. The available soil moisture content of the soil to 120-cm depth was at least 50% of available water-holding capacity (AWHC) of the profile for the fallow treatment at Lethbridge and Turin 2, and, except in some years, at Turin 1. At seeding time, there was an average of 69 mm more available water (AW) in the fallow field than in the continuous cropping field at Lethbridge and 30, 35 and 27 mm more AW in the fallow field than in the fresh stubble field of a fallow-cereal, 2-yr rotation for Lethbridge, Turin 1 and Turin 2, respectively. The overall mean precipitation conserved as soil moisture for the fallow-cereal rotation practice was 23, 29 and 23% for Lethbridge, Turin 1 and Turin 2, respectively. The significantly higher soil water content at the 90- to 120-cm depth for the fallow field than for other fields during various periods of time indicates that the soil water recharge from precipitation might be deeper in the fallow field than in continuous cropping and fresh stubble of fallow-cereal rotation fields. The deeper soil water recharge could increase the available soil moisture for crop production and it could also contribute to ground water recharge. Key words: Soil water, available water content, continuous cropping, summerfallow
EFFECTS OF POTATO CROPPING PRACTICES ON WATER RUNOFF AND SOIL EROSION
Authors: CHOW T. L. , CORMIER H. , DAIGLE J. L. , GHANEM I.
Published: March 2010

Using runoff-erosion plots (10 m wide × 30 m long), the effects of cropping practices on surface runoff and soil loss were examined on a Hommesville gravelly loam soil to evaluate the applicability of the Universal Soil Loss Equation in New Brunswick. The amount of water runoff and soil loss from continuous fallow, up-and-down slope planting of potatoes (Solanum tuberosum), and clover (Trifolium pratense) on 8 and 11% slopes were measured from 1983 to 1985. In addition, runoff and soil loss from contour planting of potatoes were measured on the 11% slope. Slope planting of potatoes resulted in higher runoff and soil loss than on fallow plots. There was considerable reduction in runoff and soil loss when potatoes were planted along the contour. Runoff and soil loss under clover were negligible. Rainfall erosion index (R) and slope length and steepness (LS) correlated well with the measured soil losses. However, both the measured soil credibility factor (K) and the cover and management factor (C) deviated markedly from the current values used for conservation planning. Key words: Universal Soil Loss Equation, rainfall erosion index, topographic factor, soil erodibility factor, cover and management factor, support practice factor
SOIL COMPACTING IMPACTS OF GRAZING IN MIXED PRAIRIE AND FESCUE GRASSLAND ECOSYSTEMS OF ALBERTA
Authors: NAETH M. A. , PLUTH D. J. , CHANASYK D. S. , BAILEY A. W. , FEDKENHEUER A. W.
Published: March 2010

The impacts of long-term grazing on compaction were assessed in mixed prairie and fescue grassland ecosystems of Alberta. Grazing regimes were of light to very heavy intensities, grazed early, late, and continuously during the growing season. Bulk density was measured with a surface moisture/density gauge and a combination moisture/density probe to 65 cm. Penetration resistance to 30 cm was measured with a cone penetrometer. Solonetzic soils were less sensitive to compaction under grazing than Chernozemic soils. Heavy intensity and/or early season grazing had greater impacts on compaction than light intensity and/or late season grazing. Under the former grazing regimes, bulk density increased to 7.5 cm at Kinsella and 65 cm at Stavely; penetration resistance increased to depths of 2.5 cm at Brooks, 15 cm at Kinsella, and 30 cm at Stavely. Heavy trampling versus regular grazing increased penetration resistance to depths of 30 and 10 cm under heavy intensity and/or early season and light intensity and/or late season grazing, respectively. Late season grazing at Brooks and light to moderate grazing at Stavely may be used as management models to reduce compaction under grazing. Trends were not as clear at Kinsella, but light June and autumn grazing had the least compacting effect. Key words: Compaction, grazing, rangelands, penetration resistance, bulk density
THE EFFECTS OF BURIED PIPELINE INSTALLATION AND FERTILIZER TREATMENTS ON CORN PRODUCTIVITY ON THREE EASTERN CANADIAN SOILS
Authors: NEILSEN DENISE , MacKENZIE A. F. , STEWART ALAN
Published: March 2010

Installation of pipelines causes soil disturbance with possible crop yield loss. Fertilizer and manure treatments may compensate for crop losses. Corn productivity was evaluated on five sites disturbed by pipeline installation in order to assess the relative sensitivity of soil types to the effects of pipeline construction during autumn and winter, and to determine the benefits of fertilizer and manure treatments. Trench, spoil bank, working side (ON-ROW) and undisturbed zones (OFF-ROW) as well as fertilizer and manure treatments were compared on three soils (Morrisburg loam, North Gower clay, Ste. Sophie loamy sand). Autumn and winter installation were compared on Morrisburg and North Gower soils. On the Ste. Sophie site only winter installation was studied. Pipeline installation did not affect corn emergence. On Morrisburg soil sites, autumn installation delayed silking, reduced plant heights and corn yields ON-ROW as compared to undisturbed soil; winter installation affected corn productivity only on the trench zone. On North Gower soil sites, pipeline installation had little effect on corn performance. At the Ste. Sophie site, installation resulted in delayed silking, and reduced plant height and yield in 1977 but improved corn yields in 1978. Fertilizer and manure treatments increased corn yields and accelerated silking at all sites. ON-ROW yields were not restored to OFF-ROW at the Morrisburg soil sites responsive to fertilizer treatments. Corn yield reductions were greater at sites with lower initial organic matter contents and higher initial bulk densities. Key words: Corn (Zea mays L.), fertilizers, manure, soil series, organic matter, bulk density
RELATIVE EFFICIENCY OF POINT-INJECTION AND SURFACE APPLICATIONS FOR N FERTILIZATION OF WINTER WHEAT
Authors: JANZEN H. H. , LINDWALL C. W. , ROPPEL C. J.
Published: March 2010

Conventional methods of N application for winter wheat often exhibit low fertilizer use efficiency. The comparative effectiveness of a new method, point-injection of N solution, was evaluated in two similar microplot field experiments established in southern Alberta. The first experiment, conducted over three site-year combinations in 1985 and 1986, compared yield response and fertilizer uptake in four spring-applied fertilizer treatments: broadcast urea-ammonium nitrate (UAN), broadcast urea, broadcast ammonium nitrate, and point-injected UAN, all applied in solution form. The second experiment, conducted at five sites in 1987, compared four spring-applied fertilizer treatments: surface-banded UAN, broadcast urea (granular), broadcast ammonium nitrate (granular), and point-injected UAN. All fertilizers were labeled with 15N to permit direct estimation of fertilizer uptake. The experiments demonstrated significant increases in fertilizer efficiency with point-injection under some conditions. In five of eight comparisons conducted over a 3-yr period, point-injection treatments exhibited significantly higher fertilizer use efficiency than conventional broadcast methods of application. Average fertilizer-N recovery by the crop at all eight sites was 37% in the point-injection treatments compared with only 26% in the broadcast ammonium nitrate treatment, the next most effective method of N application. When one site was excluded, because of possible confounding effects of application time, average recoveries were 34 and 26%, respectively. The increased efficiency of point-injected fertilizers was attributed to the direct placement of fertilizer N into the active rooting zone of the crop. The advantage of point-injection over conventional methods of application was highly variable, ranging from approximately 0 to over 100%, in part because of variations in precipitation patterns. The results of these microplot studies suggest that point-injection has potential for significant enhancement of fertilizer use efficiency in winter wheat, particularly in semi-arid production regions. Key words: 15N, nitrogen, urea, ammonium nitrate, fertilizer placement
TILLAGE-INDUCED SOIL CHANGES AND RELATED GRAIN YIELD IN A SEMI-ARID REGION
Authors: CAREFOOT J. M. , LINDWALL C. W. , NYBORG M.
Published: March 2010

Crop yields are affected by tillage-induced changes in soil chemical and physical parameters. This study was conducted to determine the tillage-induced soil changes and related grain yield and grain N concentration for two crop rotations in a semi-arid region. Soil physical and chemical properties were measured in winter wheat-barley-fallow and continuous wheat rotations under no-till (NT) and conventional till (CT). The field measurements were made in 1983 and 1984 on a Lethbridge loam and a Chin clay loam in a semi-arid region of Alberta. Soil moisture, temperature, bulk density and inorganic N were measured. The effects of tillage-induced soil changes on grain yield and grain N concentration were assessed. In 1983, at Lethbridge, tillage had no effect on grain yield. Grain yield was greater for NT than for CT crops in 1984, a year characterized by early summer drought. At Vauxhall, yield of NT crops was equal to or greater than that of CT crops except for barley in 1983, where volunteer winter wheat growth was a severe problem in the NT treatment. May soil temperatures (2-cm soil depth) for spring-seeded barley averaged 14.7 °C in the CT compared with 13.9 °C in the NT treatment. Inorganic N (0 to 30 cm) was not significantly affected by tillage in 1983, but in 1984 inorganic N was consistently greater in the CT than in the NT treatments at midseason and in the fall. The dominant effect on grain N concentration was an inverse relationship with grain yield. However, when grain yields were similar between tillage systems, greater inorganic N with the CT treatment was reflected in larger grain N concentrations for CT. Greater grain yield with NT than with CT at Lethbridge was associated with greater total soil water and improved seedbed moisture resulting in greater seed imbibition of water and plant emergence. At Vauxhall, tillage treatment did not significantly affect total soil water conservation, but greater grain yields with NT than with CT were attributed to improved plant emergence with NT. Conserving both seedbed moisture and total soil water by reducing tillage had beneficial effects on crop yield in this semi-arid region. Key words: No-till, conventional till, soil water, soil temperature, soil nitrogen
COMPARISON OF PARAMETERS OF SOIL PHOSPHATE AVAILABILITY FOR THE NORTHWESTERN CANADIAN PRAIRIE
Authors: SOON Y. K.
Published: March 2010

A greenhouse experiment was conducted to evaluate several P availability parameters using 17 soils from the Peace River region of northwestern Canada. Only one soil was calcareous; the rest were acidic. The extractants tested included alkaline bicarbonate, acidic fluoride and 0.01 M CaCl2 solutions, and an anion exchange resin. Other availability indices evaluated were phosphoric acid potentials, phosphate buffer capacity and single point P sorption indices. The phosphoric acid potentials gave the highest correlation with percent relative yield of barley dry matter obtained after about 7 wk of growth. P sorption indices were not correlated with any crop response index. The phosphate buffer capacity and resin-extractable P performed at least as well as three chemical extractants: Olsen, Kelowna and Miller-Axley (modified) extractants. These three extractions were further evaluated using yield data from 11 field experiments with barley and 10 with rapeseed. There was little to choose from between these three extractants; however, the Kelowna extractant is a multi-element extractant and more convenient to use than the Olsen method. The Kelowna extractant also has a better buffering capacity, thus giving it a slight advantage over the modified Miller-Axley method for calcareous soils. These soil tests are, however, not fully satisfactory. In the greenhouse study, the Kelowna and Olsen methods made two errors and the modified Miller-Axley method three errors in prediction of P fertilizer requirement or non-requirement for the experimental soils. Key words: Soil testing, phosphate potential, chemical extractants, P sorption index, critical level
COMPARISON OF EXCHANGEABLE Al, EXTRACTABLE Al, AND Al IN SOIL FRACTIONS
Authors: SHUMAN L. M.
Published: March 2010

Previous results indicated that the activity of Al3+ in soil solution, Al saturation of the CEC, and 0.01 M CaCl2-extractable Al were related to plant growth. Exchangeable Al values determined by 1 M KCl and 1 M NH4Cl, extractable Al values determined by 1 M NH4OAc, pH 4.8, 0.01 M CaCl2, 0.5 M CuCl2, 0.33 M LaCl3, and 0.005 M NTA, were compared with each other and to the activity of Al3+ in soil solution as well as Al in soil fractions. Aluminum in fractions was measured to determine the forms solubilized by the extradants. The fractions extracted were exchangeable [M Mg(NO3)2], organic bound, Mn oxide, amorphous Fe and Al oxide, and crystalline Fe and Al oxide. The order of Al extracted was CuCl2 > NH4OAc, [Formula: see text]. One M KCl and NH4Cl, and CuCl2, LaCl3, NTA, and NH4OAc, pH 4.8, gave similar relative Al values, especially for topsoils, and were not correlated with CaCl2-Al values. The exchangeable fraction Al [M Mg(NO3)2] was well correlated with the activity of Al3+ in the soil solution and Al saturation of the CEC. Organic fraction Al was negatively correlated with the activity of Al3+ in the soil solution indicating that organic matter can bind Al lowering its concentration in the soil solution. Aluminum in the crystalline Fe/Al oxide fraction correlated well with that extracted by CuCl2, LaCl3, NTA, and NH4OAc, pH 4.8, leading to the possible conclusion that these extradants solubilize Al from plant-unavailable fractions. Key words: Soil aluminum, aluminum extractants, aluminum fractions, exchangeable aluminum
FATE OF N APPLIED AS GREEN MANURE OR AMMONIUM FERTILIZER TO SOIL SUBSEQUENTLY CROPPED WITH SPRING WHEAT AT THREE SITES IN WESTERN CANADA
Authors: JANZEN H. H. , BOLE J. B. , BIEDERBECK V. O. , SLINKARD A. E.
Published: March 2010

There is growing interest in the use of annual legumes as green manure crops to replace conventional summerfallow in the spring wheat production systems of western Canada. A series of field experiments was established at three sites in western Canada (Lethbridge, Swift Current, and Saskatoon) in each of two seasons to quantify the N contribution of green manure to subsequent crops and organic matter reserves. 15N-labelled plant material from two annual legume species [Tangier flatpea (Lathyrus tingitanus 'Tinga') and lentil (Lens culinaris 'Indianhead')], as well as 15N-labelled ammonium sulfate, was applied to field microplots in midsummer. The following spring, an additional ammonium sulfate treatment was established and all plots were seeded to spring wheat (Triticum aestivum 'Leader' or 'Katepwa'). On average, the wheat crop recovered 14% of the green manure N compared with 36% of the fertilizer N. Conversely, the relative contribution of the green manure to the organic N pool in the surface soil layer was approximately twice that of inorganic fertilizer. This residual organic N was relatively recalcitrant to further mineralization, as was evident from minimal uptake of applied N in the second year after application. These results suggest that annual legumes can be a significant source of N to subsequent crops in the rotation, provided that N yields are sufficient. The primary advantage of green manure production, however, may be the long-term replenishment of stable organic N reserves in the soil. Key words: N mineralization, organic matter, 15N, annual legumes, green manure, lentil, pea
RELATIONSHIPS BETWEEN SOME PROPERTIES OF ORGANIC SOILS FROM THE SOUTHERN CANADIAN SHIELD
Authors: BROWN D. ANN , MATHUR S. P. , BROWN ANTON , KUSHNER D. J.
Published: March 2010

Different numerical methods used to distinguish between organic soil types are evaluated. The research was initiated by the suggestion that acid leaching from mining wastes could be prevented by capping the tailings with a self-renewing methane-producing muskeg bog, in order to prevent the penetration of oxygen to the wastes. Thirty organic soils from bogs in the mining districts of Elliot Lake, Sudbury, and Timmins, Ontario, and Noranda, Quebec, were sampled and 28 soil characteristics were measured. These characteristics, whose values are normally or lognormally distributed, were analyzed by several different statistical methods. Some characteristics indicate the existence of two populations, and others are bivariantly correlated. Canonical discriminant analysis was more successful than cluster analysis in separating the bogs into well-defined geographical groups. However, principal component analysis proved best at grouping the organic soils according to their organic and inorganic components, and we suggest that this is a suitable method for the general discrimination of organic soil types. Methane was present in all the 17 bogs tested for it, and in two very wet bogs more than 2 mmol of methane per liter were extracted. Key words: Muskeg bog, organic soils, soil characterization, principal component analysis
LE PRÉLÈVEMENT DU K PAR LA LUZERNE (Medicago sativa L.) ET SA DYNAMIQUE DANS 30 SOLS DU QUÉBEC
Authors: SIMARD R. R. , ZIZKA J. , KIMPE C. R. DE
Published: March 2010

The understanding of the kinetics of K uptake by plants is necessary for the development of predictive models aimed at optimum fertilizer use and crop yields. The objective of this work was to study the kinetics of K uptake by alfalfa, in a long-term growth chamber experiment (366 d), on 30 soils from Quebec. The soils varied in mineralogical composition and by the amounts of available K in soluble, rapidly and slowly exchangeable forms. In 28 of the 30 soils, a minimal, steady-state level of NH4OAc-K was reached after 208 d and six cuts of alfalfa. This minimal level and the K uptakes were qualitatively related to soil texture. Only soils with clay content greater than 35% were still able to supply enough K to maintain alfalfa yields. The kinetics of K uptake was described by two parabolic diffusion equations. In the first 208 d, the rate and amounts of K uptake were better predicted by extracting procedures using a monovalent cation for the exchange. The amount of HNO3-K in the soils was very significantly related to the rate (r = 0.90**) and amount of slowly exchangeable K uptake (r = 0.89**) in the last 158 d of growth. The availability of K was greater in soils rich in feldspar and vermiculite than in soils where illite is a major component. The results of this study indicate that the amounts of HNO3-K and/or the clay content should be integrated into alfalfa fertilizer requirement tables along with amounts of K in soluble and rapidly exchangeable forms for maintenance of alfalfa fields. Key words: Slowly exchangeable K, alfalfa, uptake kinetics, HNO3-K, diffusion, K uptake